src/common/config/session-config.c

   1 /*
   2  * Copyright (C) 2013 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   3  *
   4  * SPDX-License-Identifier: GPL-2.0-only
   5  *
   6  */
   7
   8 #include "lttng/tracker.h"
   9 #define _LGPL_SOURCE
  10 #include <assert.h>
  11 #include <ctype.h>
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14 #include <string.h>
  15 #include <inttypes.h>
  16 #include <dirent.h>
  17 #include <unistd.h>
  18 #include <sys/types.h>
  19 #include <sys/stat.h>
  20 #include <stdbool.h>
  21
  22 #include <common/defaults.h>
  23 #include <common/error.h>
  24 #include <common/macros.h>
  25 #include <common/utils.h>
  26 #include <common/dynamic-buffer.h>
  27 #include <common/compat/getenv.h>
  28 #include <lttng/lttng-error.h>
  29 #include <libxml/parser.h>
  30 #include <libxml/valid.h>
  31 #include <libxml/xmlschemas.h>
  32 #include <libxml/tree.h>
  33 #include <lttng/lttng.h>
  34 #include <lttng/snapshot.h>
  35 #include <lttng/rotation.h>
  36 #include <lttng/userspace-probe.h>
  37
  38 #include "session-config.h"
  39 #include "config-internal.h"
  40
  41 #define CONFIG_USERSPACE_PROBE_LOOKUP_METHOD_NAME_MAX_LEN 7
  42
  43 struct handler_filter_args {
  44         const char* section;
  45         config_entry_handler_cb handler;
  46         void *user_data;
  47 };
  48
  49 struct session_config_validation_ctx {
  50         xmlSchemaParserCtxtPtr parser_ctx;
  51         xmlSchemaPtr schema;
  52         xmlSchemaValidCtxtPtr schema_validation_ctx;
  53 };
  54
  55 LTTNG_HIDDEN const char * const config_element_all = "all";
  56 const char * const config_str_yes = "yes";
  57 const char * const config_str_true = "true";
  58 const char * const config_str_on = "on";
  59 const char * const config_str_no = "no";
  60 const char * const config_str_false = "false";
  61 const char * const config_str_off = "off";
  62 const char * const config_xml_encoding = "UTF-8";
  63 const size_t config_xml_encoding_bytes_per_char = 2;    /* Size of the encoding's largest character */
  64 const char * const config_xml_indent_string = "\t";
  65 const char * const config_xml_true = "true";
  66 const char * const config_xml_false = "false";
  67
  68 const char * const config_element_channel = "channel";
  69 const char * const config_element_channels = "channels";
  70 const char * const config_element_domain = "domain";
  71 const char * const config_element_domains = "domains";
  72 const char * const config_element_event = "event";
  73 const char * const config_element_events = "events";
  74 const char * const config_element_context = "context";
  75 const char * const config_element_contexts = "contexts";
  76 const char * const config_element_attributes = "attributes";
  77 const char * const config_element_exclusion = "exclusion";
  78 const char * const config_element_exclusions = "exclusions";
  79 const char * const config_element_function_attributes = "function_attributes";
  80 const char * const config_element_probe_attributes = "probe_attributes";
  81 const char * const config_element_symbol_name = "symbol_name";
  82 const char * const config_element_address = "address";
  83 const char * const config_element_offset = "offset";
  84
  85 LTTNG_HIDDEN const char * const config_element_userspace_probe_lookup = "lookup_method";
  86 LTTNG_HIDDEN const char * const config_element_userspace_probe_lookup_function_default = "DEFAULT";
  87 LTTNG_HIDDEN const char * const config_element_userspace_probe_lookup_function_elf = "ELF";
  88 LTTNG_HIDDEN const char * const config_element_userspace_probe_lookup_tracepoint_sdt = "SDT";
  89 LTTNG_HIDDEN const char * const config_element_userspace_probe_location_binary_path = "binary_path";
  90 LTTNG_HIDDEN const char * const config_element_userspace_probe_function_attributes = "userspace_probe_function_attributes";
  91 LTTNG_HIDDEN const char * const config_element_userspace_probe_function_location_function_name = "function_name";
  92 LTTNG_HIDDEN const char * const config_element_userspace_probe_tracepoint_attributes = "userspace_probe_tracepoint_attributes";
  93 LTTNG_HIDDEN const char * const config_element_userspace_probe_tracepoint_location_provider_name = "provider_name";
  94 LTTNG_HIDDEN const char * const config_element_userspace_probe_tracepoint_location_probe_name = "probe_name";
  95
  96 const char * const config_element_name = "name";
  97 const char * const config_element_enabled = "enabled";
  98 const char * const config_element_overwrite_mode = "overwrite_mode";
  99 const char * const config_element_subbuf_size = "subbuffer_size";
 100 const char * const config_element_num_subbuf = "subbuffer_count";
 101 const char * const config_element_switch_timer_interval = "switch_timer_interval";
 102 const char * const config_element_read_timer_interval = "read_timer_interval";
 103 LTTNG_HIDDEN const char * const config_element_monitor_timer_interval = "monitor_timer_interval";
 104 LTTNG_HIDDEN const char * const config_element_blocking_timeout = "blocking_timeout";
 105 const char * const config_element_output = "output";
 106 const char * const config_element_output_type = "output_type";
 107 const char * const config_element_tracefile_size = "tracefile_size";
 108 const char * const config_element_tracefile_count = "tracefile_count";
 109 const char * const config_element_live_timer_interval = "live_timer_interval";
 110 LTTNG_HIDDEN const char * const config_element_discarded_events = "discarded_events";
 111 LTTNG_HIDDEN const char * const config_element_lost_packets = "lost_packets";
 112 const char * const config_element_type = "type";
 113 const char * const config_element_buffer_type = "buffer_type";
 114 const char * const config_element_session = "session";
 115 const char * const config_element_sessions = "sessions";
 116 LTTNG_HIDDEN const char * const config_element_context_perf = "perf";
 117 LTTNG_HIDDEN const char * const config_element_context_app = "app";
 118 LTTNG_HIDDEN const char * const config_element_context_app_provider_name = "provider_name";
 119 LTTNG_HIDDEN const char * const config_element_context_app_ctx_name = "ctx_name";
 120 const char * const config_element_config = "config";
 121 const char * const config_element_started = "started";
 122 const char * const config_element_snapshot_mode = "snapshot_mode";
 123 const char * const config_element_loglevel = "loglevel";
 124 const char * const config_element_loglevel_type = "loglevel_type";
 125 const char * const config_element_filter = "filter";
 126 LTTNG_HIDDEN const char * const config_element_filter_expression = "filter_expression";
 127 const char * const config_element_snapshot_outputs = "snapshot_outputs";
 128 const char * const config_element_consumer_output = "consumer_output";
 129 const char * const config_element_destination = "destination";
 130 const char * const config_element_path = "path";
 131 const char * const config_element_net_output = "net_output";
 132 const char * const config_element_control_uri = "control_uri";
 133 const char * const config_element_data_uri = "data_uri";
 134 const char * const config_element_max_size = "max_size";
 135 const char * const config_element_pid = "pid";
 136 const char * const config_element_pids = "pids";
 137 const char * const config_element_shared_memory_path = "shared_memory_path";
 138
 139 LTTNG_HIDDEN const char * const config_element_process_attr_id = "id";
 140 LTTNG_HIDDEN const char * const config_element_process_attr_tracker_pid = "pid_process_attr_tracker";
 141 LTTNG_HIDDEN const char * const config_element_process_attr_tracker_vpid = "vpid_process_attr_tracker";
 142 LTTNG_HIDDEN const char * const config_element_process_attr_tracker_uid = "uid_process_attr_tracker";
 143 LTTNG_HIDDEN const char * const config_element_process_attr_tracker_vuid = "vuid_process_attr_tracker";
 144 LTTNG_HIDDEN const char * const config_element_process_attr_tracker_gid = "gid_process_attr_tracker";
 145 LTTNG_HIDDEN const char * const config_element_process_attr_tracker_vgid = "vgid_process_attr_tracker";
 146 LTTNG_HIDDEN const char * const config_element_process_attr_trackers = "process_attr_trackers";
 147 LTTNG_HIDDEN const char * const config_element_process_attr_values = "process_attr_values";
 148 LTTNG_HIDDEN const char * const config_element_process_attr_value_type = "process_attr_value_type";
 149 LTTNG_HIDDEN const char * const config_element_process_attr_pid_value = "pid";
 150 LTTNG_HIDDEN const char * const config_element_process_attr_vpid_value = "vpid";
 151 LTTNG_HIDDEN const char * const config_element_process_attr_uid_value = "uid";
 152 LTTNG_HIDDEN const char * const config_element_process_attr_vuid_value = "vuid";
 153 LTTNG_HIDDEN const char * const config_element_process_attr_gid_value = "gid";
 154 LTTNG_HIDDEN const char * const config_element_process_attr_vgid_value = "vgid";
 155 LTTNG_HIDDEN const char * const config_element_process_attr_tracker_type = "process_attr_tracker_type";
 156
 157 /* Used for support of legacy tracker serialization (< 2.12). */
 158 LTTNG_HIDDEN const char * const config_element_trackers_legacy = "trackers";
 159 LTTNG_HIDDEN const char * const config_element_pid_tracker_legacy = "pid_tracker";
 160 LTTNG_HIDDEN const char * const config_element_tracker_targets_legacy = "targets";
 161 LTTNG_HIDDEN const char * const config_element_tracker_pid_target_legacy = "pid_target";
 162 LTTNG_HIDDEN const char * const config_element_tracker_pid_legacy = "pid";
 163
 164 LTTNG_HIDDEN const char * const config_element_rotation_schedules = "rotation_schedules";
 165 LTTNG_HIDDEN const char * const config_element_rotation_schedule_periodic = "periodic";
 166 LTTNG_HIDDEN const char * const config_element_rotation_schedule_periodic_time_us = "time_us";
 167 LTTNG_HIDDEN const char * const config_element_rotation_schedule_size_threshold = "size_threshold";
 168 LTTNG_HIDDEN const char * const config_element_rotation_schedule_size_threshold_bytes = "bytes";
 169
 170 const char * const config_domain_type_kernel = "KERNEL";
 171 const char * const config_domain_type_ust = "UST";
 172 const char * const config_domain_type_jul = "JUL";
 173 const char * const config_domain_type_log4j = "LOG4J";
 174 const char * const config_domain_type_python = "PYTHON";
 175
 176 const char * const config_buffer_type_per_pid = "PER_PID";
 177 const char * const config_buffer_type_per_uid = "PER_UID";
 178 const char * const config_buffer_type_global = "GLOBAL";
 179
 180 const char * const config_overwrite_mode_discard = "DISCARD";
 181 const char * const config_overwrite_mode_overwrite = "OVERWRITE";
 182
 183 const char * const config_output_type_splice = "SPLICE";
 184 const char * const config_output_type_mmap = "MMAP";
 185
 186 const char * const config_loglevel_type_all = "ALL";
 187 const char * const config_loglevel_type_range = "RANGE";
 188 const char * const config_loglevel_type_single = "SINGLE";
 189
 190 const char * const config_event_type_all = "ALL";
 191 const char * const config_event_type_tracepoint = "TRACEPOINT";
 192 const char * const config_event_type_probe = "PROBE";
 193 LTTNG_HIDDEN const char * const config_event_type_userspace_probe = "USERSPACE_PROBE";
 194 const char * const config_event_type_function = "FUNCTION";
 195 const char * const config_event_type_function_entry = "FUNCTION_ENTRY";
 196 const char * const config_event_type_noop = "NOOP";
 197 const char * const config_event_type_syscall = "SYSCALL";
 198 const char * const config_event_type_kprobe = "KPROBE";
 199 const char * const config_event_type_kretprobe = "KRETPROBE";
 200
 201 const char * const config_event_context_pid = "PID";
 202 const char * const config_event_context_procname = "PROCNAME";
 203 const char * const config_event_context_prio = "PRIO";
 204 const char * const config_event_context_nice = "NICE";
 205 const char * const config_event_context_vpid = "VPID";
 206 const char * const config_event_context_tid = "TID";
 207 const char * const config_event_context_vtid = "VTID";
 208 const char * const config_event_context_ppid = "PPID";
 209 const char * const config_event_context_vppid = "VPPID";
 210 const char * const config_event_context_pthread_id = "PTHREAD_ID";
 211 const char * const config_event_context_hostname = "HOSTNAME";
 212 const char * const config_event_context_ip = "IP";
 213 const char * const config_event_context_perf_thread_counter = "PERF_THREAD_COUNTER";
 214 LTTNG_HIDDEN const char * const config_event_context_app = "APP";
 215 LTTNG_HIDDEN const char * const config_event_context_interruptible = "INTERRUPTIBLE";
 216 LTTNG_HIDDEN const char * const config_event_context_preemptible = "PREEMPTIBLE";
 217 LTTNG_HIDDEN const char * const config_event_context_need_reschedule = "NEED_RESCHEDULE";
 218 LTTNG_HIDDEN const char * const config_event_context_migratable = "MIGRATABLE";
 219 LTTNG_HIDDEN const char * const config_event_context_callstack_user= "CALLSTACK_USER";
 220 LTTNG_HIDDEN const char * const config_event_context_callstack_kernel = "CALLSTACK_KERNEL";
 221 LTTNG_HIDDEN const char * const config_event_context_cgroup_ns = "CGROUP_NS";
 222 LTTNG_HIDDEN const char * const config_event_context_ipc_ns = "IPC_NS";
 223 LTTNG_HIDDEN const char * const config_event_context_mnt_ns = "MNT_NS";
 224 LTTNG_HIDDEN const char * const config_event_context_net_ns = "NET_NS";
 225 LTTNG_HIDDEN const char * const config_event_context_pid_ns = "PID_NS";
 226 LTTNG_HIDDEN const char * const config_event_context_time_ns = "TIME_NS";
 227 LTTNG_HIDDEN const char * const config_event_context_user_ns = "USER_NS";
 228 LTTNG_HIDDEN const char * const config_event_context_uts_ns = "UTS_NS";
 229 LTTNG_HIDDEN const char * const config_event_context_uid = "UID";
 230 LTTNG_HIDDEN const char * const config_event_context_euid = "EUID";
 231 LTTNG_HIDDEN const char * const config_event_context_suid = "SUID";
 232 LTTNG_HIDDEN const char * const config_event_context_gid = "GID";
 233 LTTNG_HIDDEN const char * const config_event_context_egid = "EGID";
 234 LTTNG_HIDDEN const char * const config_event_context_sgid = "SGID";
 235 LTTNG_HIDDEN const char * const config_event_context_vuid = "VUID";
 236 LTTNG_HIDDEN const char * const config_event_context_veuid = "VEUID";
 237 LTTNG_HIDDEN const char * const config_event_context_vsuid = "VSUID";
 238 LTTNG_HIDDEN const char * const config_event_context_vgid = "VGID";
 239 LTTNG_HIDDEN const char * const config_event_context_vegid = "VEGID";
 240 LTTNG_HIDDEN const char * const config_event_context_vsgid = "VSGID";
 241
 242 /* Deprecated symbols */
 243 const char * const config_element_perf;
 244
 245 enum process_event_node_phase {
 246         CREATION = 0,
 247         ENABLE = 1,
 248 };
 249
 250 struct consumer_output {
 251         int enabled;
 252         char *path;
 253         char *control_uri;
 254         char *data_uri;
 255 };
 256
 257 static int config_entry_handler_filter(struct handler_filter_args *args,
 258                 const char *section, const char *name, const char *value)
 259 {
 260         int ret = 0;
 261         struct config_entry entry = { section, name, value };
 262
 263         assert(args);
 264
 265         if (!section || !name || !value) {
 266                 ret = -EIO;
 267                 goto end;
 268         }
 269
 270         if (args->section) {
 271                 if (strcmp(args->section, section)) {
 272                         goto end;
 273                 }
 274         }
 275
 276         ret = args->handler(&entry, args->user_data);
 277 end:
 278         return ret;
 279 }
 280
 281 LTTNG_HIDDEN
 282 int config_get_section_entries(const char *override_path, const char *section,
 283                 config_entry_handler_cb handler, void *user_data)
 284 {
 285         int ret = 0;
 286         const char *path;
 287         FILE *config_file = NULL;
 288         struct handler_filter_args filter = { section, handler, user_data };
 289
 290         /* First, try system-wide conf. file. */
 291         path = DEFAULT_DAEMON_SYSTEM_CONFIGPATH;
 292
 293         config_file = fopen(path, "r");
 294         if (config_file) {
 295                 DBG("Loading daemon conf file at %s", path);
 296                 /*
 297                  * Return value is not very important here since error or not, we
 298                  * continue and try the next possible conf. file.
 299                  */
 300                 (void) ini_parse_file(config_file,
 301                                 (ini_entry_handler) config_entry_handler_filter,
 302                                 (void *) &filter);
 303                 fclose(config_file);
 304         }
 305
 306         /* Second is the user local configuration. */
 307         path = utils_get_home_dir();
 308         if (path) {
 309                 char fullpath[PATH_MAX];
 310
 311                 ret = snprintf(fullpath, sizeof(fullpath),
 312                                 DEFAULT_DAEMON_HOME_CONFIGPATH, path);
 313                 if (ret < 0) {
 314                         PERROR("snprintf user conf. path");
 315                         goto error;
 316                 }
 317
 318                 config_file = fopen(fullpath, "r");
 319                 if (config_file) {
 320                         DBG("Loading daemon user conf file at %s", path);
 321                         /*
 322                          * Return value is not very important here since error or not, we
 323                          * continue and try the next possible conf. file.
 324                          */
 325                         (void) ini_parse_file(config_file,
 326                                         (ini_entry_handler) config_entry_handler_filter,
 327                                         (void *) &filter);
 328                         fclose(config_file);
 329                 }
 330         }
 331
 332         /* Final path is the one that the user might have provided. */
 333         if (override_path) {
 334                 config_file = fopen(override_path, "r");
 335                 if (config_file) {
 336                         DBG("Loading daemon command line conf file at %s", override_path);
 337                         (void) ini_parse_file(config_file,
 338                                         (ini_entry_handler) config_entry_handler_filter,
 339                                         (void *) &filter);
 340                         fclose(config_file);
 341                 } else {
 342                         ERR("Failed to open daemon configuration file at %s",
 343                                 override_path);
 344                         ret = -ENOENT;
 345                         goto error;
 346                 }
 347         }
 348
 349         /* Everything went well. */
 350         ret = 0;
 351
 352 error:
 353         return ret;
 354 }
 355
 356 LTTNG_HIDDEN
 357 int config_parse_value(const char *value)
 358 {
 359         int i, ret = 0;
 360         char *endptr, *lower_str;
 361         size_t len;
 362         unsigned long v;
 363
 364         len = strlen(value);
 365         if (!len) {
 366                 ret = -1;
 367                 goto end;
 368         }
 369
 370         v = strtoul(value, &endptr, 10);
 371         if (endptr != value) {
 372                 ret = v;
 373                 goto end;
 374         }
 375
 376         lower_str = zmalloc(len + 1);
 377         if (!lower_str) {
 378                 PERROR("zmalloc");
 379                 ret = -errno;
 380                 goto end;
 381         }
 382
 383         for (i = 0; i < len; i++) {
 384                 lower_str[i] = tolower(value[i]);
 385         }
 386
 387         if (!strcmp(lower_str, config_str_yes) ||
 388                 !strcmp(lower_str, config_str_true) ||
 389                 !strcmp(lower_str, config_str_on)) {
 390                 ret = 1;
 391         } else if (!strcmp(lower_str, config_str_no) ||
 392                 !strcmp(lower_str, config_str_false) ||
 393                 !strcmp(lower_str, config_str_off)) {
 394                 ret = 0;
 395         } else {
 396                 ret = -1;
 397         }
 398
 399         free(lower_str);
 400 end:
 401         return ret;
 402 }
 403
 404 /*
 405  * Returns a xmlChar string which must be released using xmlFree().
 406  */
 407 static xmlChar *encode_string(const char *in_str)
 408 {
 409         xmlChar *out_str = NULL;
 410         xmlCharEncodingHandlerPtr handler;
 411         int out_len, ret, in_len;
 412
 413         assert(in_str);
 414
 415         handler = xmlFindCharEncodingHandler(config_xml_encoding);
 416         if (!handler) {
 417                 ERR("xmlFindCharEncodingHandler return NULL!. Configure issue!");
 418                 goto end;
 419         }
 420
 421         in_len = strlen(in_str);
 422         /*
 423          * Add 1 byte for the NULL terminted character. The factor 4 here is
 424          * used because UTF-8 characters can take up to 4 bytes.
 425          */
 426         out_len = (in_len * 4) + 1;
 427         out_str = xmlMalloc(out_len);
 428         if (!out_str) {
 429                 goto end;
 430         }
 431
 432         ret = handler->input(out_str, &out_len, (const xmlChar *) in_str, &in_len);
 433         if (ret < 0) {
 434                 xmlFree(out_str);
 435                 out_str = NULL;
 436                 goto end;
 437         }
 438
 439         /* out_len is now the size of out_str */
 440         out_str[out_len] = '\0';
 441 end:
 442         return out_str;
 443 }
 444
 445 LTTNG_HIDDEN
 446 struct config_writer *config_writer_create(int fd_output, int indent)
 447 {
 448         int ret;
 449         struct config_writer *writer;
 450         xmlOutputBufferPtr buffer;
 451
 452         writer = zmalloc(sizeof(struct config_writer));
 453         if (!writer) {
 454                 PERROR("zmalloc config_writer_create");
 455                 goto end;
 456         }
 457
 458         buffer = xmlOutputBufferCreateFd(fd_output, NULL);
 459         if (!buffer) {
 460                 goto error_destroy;
 461         }
 462
 463         writer->writer = xmlNewTextWriter(buffer);
 464         ret = xmlTextWriterStartDocument(writer->writer, NULL,
 465                 config_xml_encoding, NULL);
 466         if (ret < 0) {
 467                 goto error_destroy;
 468         }
 469
 470         ret = xmlTextWriterSetIndentString(writer->writer,
 471                 BAD_CAST config_xml_indent_string);
 472         if (ret) {
 473                 goto error_destroy;
 474         }
 475
 476         ret = xmlTextWriterSetIndent(writer->writer, indent);
 477         if (ret) {
 478                 goto error_destroy;
 479         }
 480
 481 end:
 482         return writer;
 483 error_destroy:
 484         config_writer_destroy(writer);
 485         return NULL;
 486 }
 487
 488 LTTNG_HIDDEN
 489 int config_writer_destroy(struct config_writer *writer)
 490 {
 491         int ret = 0;
 492
 493         if (!writer) {
 494                 ret = -EINVAL;
 495                 goto end;
 496         }
 497
 498         if (xmlTextWriterEndDocument(writer->writer) < 0) {
 499                 WARN("Could not close XML document");
 500                 ret = -EIO;
 501         }
 502
 503         if (writer->writer) {
 504                 xmlFreeTextWriter(writer->writer);
 505         }
 506
 507         free(writer);
 508 end:
 509         return ret;
 510 }
 511
 512 LTTNG_HIDDEN
 513 int config_writer_open_element(struct config_writer *writer,
 514         const char *element_name)
 515 {
 516         int ret;
 517         xmlChar *encoded_element_name;
 518
 519         if (!writer || !writer->writer || !element_name || !element_name[0]) {
 520                 ret = -1;
 521                 goto end;
 522         }
 523
 524         encoded_element_name = encode_string(element_name);
 525         if (!encoded_element_name) {
 526                 ret = -1;
 527                 goto end;
 528         }
 529
 530         ret = xmlTextWriterStartElement(writer->writer, encoded_element_name);
 531         xmlFree(encoded_element_name);
 532 end:
 533         return ret >= 0 ? 0 : ret;
 534 }
 535
 536 LTTNG_HIDDEN
 537 int config_writer_write_attribute(struct config_writer *writer,
 538                 const char *name, const char *value)
 539 {
 540         int ret;
 541         xmlChar *encoded_name = NULL;
 542         xmlChar *encoded_value = NULL;
 543
 544         if (!writer || !writer->writer || !name || !name[0]) {
 545                 ret = -1;
 546                 goto end;
 547         }
 548
 549         encoded_name = encode_string(name);
 550         if (!encoded_name) {
 551                 ret = -1;
 552                 goto end;
 553         }
 554
 555         encoded_value = encode_string(value);
 556         if (!encoded_value) {
 557                 ret = -1;
 558                 goto end;
 559         }
 560
 561         ret = xmlTextWriterWriteAttribute(writer->writer, encoded_name,
 562                         encoded_value);
 563 end:
 564         xmlFree(encoded_name);
 565         xmlFree(encoded_value);
 566         return ret >= 0 ? 0 : ret;
 567 }
 568
 569 LTTNG_HIDDEN
 570 int config_writer_close_element(struct config_writer *writer)
 571 {
 572         int ret;
 573
 574         if (!writer || !writer->writer) {
 575                 ret = -1;
 576                 goto end;
 577         }
 578
 579         ret = xmlTextWriterEndElement(writer->writer);
 580 end:
 581         return ret >= 0 ? 0 : ret;
 582 }
 583
 584 LTTNG_HIDDEN
 585 int config_writer_write_element_unsigned_int(struct config_writer *writer,
 586                 const char *element_name, uint64_t value)
 587 {
 588         int ret;
 589         xmlChar *encoded_element_name;
 590
 591         if (!writer || !writer->writer || !element_name || !element_name[0]) {
 592                 ret = -1;
 593                 goto end;
 594         }
 595
 596         encoded_element_name = encode_string(element_name);
 597         if (!encoded_element_name) {
 598                 ret = -1;
 599                 goto end;
 600         }
 601
 602         ret = xmlTextWriterWriteFormatElement(writer->writer,
 603                 encoded_element_name, "%" PRIu64, value);
 604         xmlFree(encoded_element_name);
 605 end:
 606         return ret >= 0 ? 0 : ret;
 607 }
 608
 609 LTTNG_HIDDEN
 610 int config_writer_write_element_signed_int(struct config_writer *writer,
 611                 const char *element_name, int64_t value)
 612 {
 613         int ret;
 614         xmlChar *encoded_element_name;
 615
 616         if (!writer || !writer->writer || !element_name || !element_name[0]) {
 617                 ret = -1;
 618                 goto end;
 619         }
 620
 621         encoded_element_name = encode_string(element_name);
 622         if (!encoded_element_name) {
 623                 ret = -1;
 624                 goto end;
 625         }
 626
 627         ret = xmlTextWriterWriteFormatElement(writer->writer,
 628                 encoded_element_name, "%" PRIi64, value);
 629         xmlFree(encoded_element_name);
 630 end:
 631         return ret >= 0 ? 0 : ret;
 632 }
 633
 634 LTTNG_HIDDEN
 635 int config_writer_write_element_bool(struct config_writer *writer,
 636                 const char *element_name, int value)
 637 {
 638         return config_writer_write_element_string(writer, element_name,
 639                 value ? config_xml_true : config_xml_false);
 640 }
 641
 642 LTTNG_HIDDEN
 643 int config_writer_write_element_string(struct config_writer *writer,
 644                 const char *element_name, const char *value)
 645 {
 646         int ret;
 647         xmlChar *encoded_element_name = NULL;
 648         xmlChar *encoded_value = NULL;
 649
 650         if (!writer || !writer->writer || !element_name || !element_name[0] ||
 651                 !value) {
 652                 ret = -1;
 653                 goto end;
 654         }
 655
 656         encoded_element_name = encode_string(element_name);
 657         if (!encoded_element_name) {
 658                 ret = -1;
 659                 goto end;
 660         }
 661
 662         encoded_value = encode_string(value);
 663         if (!encoded_value) {
 664                 ret = -1;
 665                 goto end;
 666         }
 667
 668         ret = xmlTextWriterWriteElement(writer->writer, encoded_element_name,
 669                         encoded_value);
 670 end:
 671         xmlFree(encoded_element_name);
 672         xmlFree(encoded_value);
 673         return ret >= 0 ? 0 : ret;
 674 }
 675
 676 static
 677 void xml_error_handler(void *ctx, const char *format, ...)
 678 {
 679         char *errMsg;
 680         va_list args;
 681         int ret;
 682
 683         va_start(args, format);
 684         ret = vasprintf(&errMsg, format, args);
 685         va_end(args);
 686         if (ret == -1) {
 687                 ERR("String allocation failed in xml error handler");
 688                 return;
 689         }
 690
 691         fprintf(stderr, "XML Error: %s", errMsg);
 692         free(errMsg);
 693 }
 694
 695 static
 696 void fini_session_config_validation_ctx(
 697         struct session_config_validation_ctx *ctx)
 698 {
 699         if (ctx->parser_ctx) {
 700                 xmlSchemaFreeParserCtxt(ctx->parser_ctx);
 701         }
 702
 703         if (ctx->schema) {
 704                 xmlSchemaFree(ctx->schema);
 705         }
 706
 707         if (ctx->schema_validation_ctx) {
 708                 xmlSchemaFreeValidCtxt(ctx->schema_validation_ctx);
 709         }
 710
 711         memset(ctx, 0, sizeof(struct session_config_validation_ctx));
 712 }
 713
 714 static
 715 char *get_session_config_xsd_path(void)
 716 {
 717         char *xsd_path;
 718         const char *base_path = lttng_secure_getenv(DEFAULT_SESSION_CONFIG_XSD_PATH_ENV);
 719         size_t base_path_len;
 720         size_t max_path_len;
 721
 722         if (!base_path) {
 723                 base_path = DEFAULT_SESSION_CONFIG_XSD_PATH;
 724         }
 725
 726         base_path_len = strlen(base_path);
 727         max_path_len = base_path_len +
 728                 sizeof(DEFAULT_SESSION_CONFIG_XSD_FILENAME) + 1;
 729         xsd_path = zmalloc(max_path_len);
 730         if (!xsd_path) {
 731                 goto end;
 732         }
 733
 734         strcpy(xsd_path, base_path);
 735         if (xsd_path[base_path_len - 1] != '/') {
 736                 xsd_path[base_path_len++] = '/';
 737         }
 738
 739         strcpy(xsd_path + base_path_len, DEFAULT_SESSION_CONFIG_XSD_FILENAME);
 740 end:
 741         return xsd_path;
 742 }
 743
 744 static
 745 int init_session_config_validation_ctx(
 746         struct session_config_validation_ctx *ctx)
 747 {
 748         int ret;
 749         char *xsd_path = get_session_config_xsd_path();
 750
 751         if (!xsd_path) {
 752                 ret = -LTTNG_ERR_NOMEM;
 753                 goto end;
 754         }
 755
 756         ctx->parser_ctx = xmlSchemaNewParserCtxt(xsd_path);
 757         if (!ctx->parser_ctx) {
 758                 ERR("XSD parser context creation failed");
 759                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
 760                 goto end;
 761         }
 762         xmlSchemaSetParserErrors(ctx->parser_ctx, xml_error_handler,
 763                 xml_error_handler, NULL);
 764
 765         ctx->schema = xmlSchemaParse(ctx->parser_ctx);
 766         if (!ctx->schema) {
 767                 ERR("XSD parsing failed");
 768                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
 769                 goto end;
 770         }
 771
 772         ctx->schema_validation_ctx = xmlSchemaNewValidCtxt(ctx->schema);
 773         if (!ctx->schema_validation_ctx) {
 774                 ERR("XSD validation context creation failed");
 775                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
 776                 goto end;
 777         }
 778
 779         xmlSchemaSetValidErrors(ctx->schema_validation_ctx, xml_error_handler,
 780                         xml_error_handler, NULL);
 781         ret = 0;
 782
 783 end:
 784         if (ret) {
 785                 fini_session_config_validation_ctx(ctx);
 786         }
 787
 788         free(xsd_path);
 789         return ret;
 790 }
 791
 792 static
 793 int parse_uint(xmlChar *str, uint64_t *val)
 794 {
 795         int ret;
 796         char *endptr;
 797
 798         if (!str || !val) {
 799                 ret = -1;
 800                 goto end;
 801         }
 802
 803         *val = strtoull((const char *) str, &endptr, 10);
 804         if (!endptr || *endptr) {
 805                 ret = -1;
 806         } else {
 807                 ret = 0;
 808         }
 809
 810 end:
 811         return ret;
 812 }
 813
 814 static
 815 int parse_int(xmlChar *str, int64_t *val)
 816 {
 817         int ret;
 818         char *endptr;
 819
 820         if (!str || !val) {
 821                 ret = -1;
 822                 goto end;
 823         }
 824
 825         *val = strtoll((const char *) str, &endptr, 10);
 826         if (!endptr || *endptr) {
 827                 ret = -1;
 828         } else {
 829                 ret = 0;
 830         }
 831
 832 end:
 833         return ret;
 834 }
 835
 836 static
 837 int parse_bool(xmlChar *str, int *val)
 838 {
 839         int ret = 0;
 840
 841         if (!str || !val) {
 842                 ret = -1;
 843                 goto end;
 844         }
 845
 846         if (!strcmp((const char *) str, config_xml_true)) {
 847                 *val = 1;
 848         } else if (!strcmp((const char *) str, config_xml_false)) {
 849                 *val = 0;
 850         } else {
 851                 WARN("Invalid boolean value encoutered (%s).",
 852                         (const char *) str);
 853                 ret = -1;
 854         }
 855 end:
 856         return ret;
 857 }
 858
 859 static
 860 int get_domain_type(xmlChar *domain)
 861 {
 862         int ret;
 863
 864         if (!domain) {
 865                 goto error;
 866         }
 867
 868         if (!strcmp((char *) domain, config_domain_type_kernel)) {
 869                 ret = LTTNG_DOMAIN_KERNEL;
 870         } else if (!strcmp((char *) domain, config_domain_type_ust)) {
 871                 ret = LTTNG_DOMAIN_UST;
 872         } else if (!strcmp((char *) domain, config_domain_type_jul)) {
 873                 ret = LTTNG_DOMAIN_JUL;
 874         } else if (!strcmp((char *) domain, config_domain_type_log4j)) {
 875                 ret = LTTNG_DOMAIN_LOG4J;
 876         } else if (!strcmp((char *) domain, config_domain_type_python)) {
 877                 ret = LTTNG_DOMAIN_PYTHON;
 878         } else {
 879                 goto error;
 880         }
 881
 882         return ret;
 883 error:
 884         return -1;
 885 }
 886
 887 static
 888 int get_buffer_type(xmlChar *buffer_type)
 889 {
 890         int ret;
 891
 892         if (!buffer_type) {
 893                 goto error;
 894         }
 895
 896         if (!strcmp((char *) buffer_type, config_buffer_type_global)) {
 897                 ret = LTTNG_BUFFER_GLOBAL;
 898         } else if (!strcmp((char *) buffer_type, config_buffer_type_per_uid)) {
 899                 ret = LTTNG_BUFFER_PER_UID;
 900         } else if (!strcmp((char *) buffer_type, config_buffer_type_per_pid)) {
 901                 ret = LTTNG_BUFFER_PER_PID;
 902         } else {
 903                 goto error;
 904         }
 905
 906         return ret;
 907 error:
 908         return -1;
 909 }
 910
 911 static
 912 int get_overwrite_mode(xmlChar *overwrite_mode)
 913 {
 914         int ret;
 915
 916         if (!overwrite_mode) {
 917                 goto error;
 918         }
 919
 920         if (!strcmp((char *) overwrite_mode, config_overwrite_mode_overwrite)) {
 921                 ret = 1;
 922         } else if (!strcmp((char *) overwrite_mode,
 923                 config_overwrite_mode_discard)) {
 924                 ret = 0;
 925         } else {
 926                 goto error;
 927         }
 928
 929         return ret;
 930 error:
 931         return -1;
 932 }
 933
 934 static
 935 int get_output_type(xmlChar *output_type)
 936 {
 937         int ret;
 938
 939         if (!output_type) {
 940                 goto error;
 941         }
 942
 943         if (!strcmp((char *) output_type, config_output_type_mmap)) {
 944                 ret = LTTNG_EVENT_MMAP;
 945         } else if (!strcmp((char *) output_type, config_output_type_splice)) {
 946                 ret = LTTNG_EVENT_SPLICE;
 947         } else {
 948                 goto error;
 949         }
 950
 951         return ret;
 952 error:
 953         return -1;
 954 }
 955
 956 static
 957 int get_event_type(xmlChar *event_type)
 958 {
 959         int ret;
 960
 961         if (!event_type) {
 962                 goto error;
 963         }
 964
 965         if (!strcmp((char *) event_type, config_event_type_all)) {
 966                 ret = LTTNG_EVENT_ALL;
 967         } else if (!strcmp((char *) event_type, config_event_type_tracepoint)) {
 968                 ret = LTTNG_EVENT_TRACEPOINT;
 969         } else if (!strcmp((char *) event_type, config_event_type_probe)) {
 970                 ret = LTTNG_EVENT_PROBE;
 971         } else if (!strcmp((char *) event_type,
 972                                 config_event_type_userspace_probe)) {
 973                 ret = LTTNG_EVENT_USERSPACE_PROBE;
 974         } else if (!strcmp((char *) event_type, config_event_type_function)) {
 975                 ret = LTTNG_EVENT_FUNCTION;
 976         } else if (!strcmp((char *) event_type,
 977                                 config_event_type_function_entry)) {
 978                 ret = LTTNG_EVENT_FUNCTION_ENTRY;
 979         } else if (!strcmp((char *) event_type, config_event_type_noop)) {
 980                 ret = LTTNG_EVENT_NOOP;
 981         } else if (!strcmp((char *) event_type, config_event_type_syscall)) {
 982                 ret = LTTNG_EVENT_SYSCALL;
 983         } else {
 984                 goto error;
 985         }
 986
 987         return ret;
 988 error:
 989         return -1;
 990 }
 991
 992 static
 993 int get_loglevel_type(xmlChar *loglevel_type)
 994 {
 995         int ret;
 996
 997         if (!loglevel_type) {
 998                 goto error;
 999         }
1000
1001         if (!strcmp((char *) loglevel_type, config_loglevel_type_all)) {
1002                 ret = LTTNG_EVENT_LOGLEVEL_ALL;
1003         } else if (!strcmp((char *) loglevel_type,
1004                 config_loglevel_type_range)) {
1005                 ret = LTTNG_EVENT_LOGLEVEL_RANGE;
1006         } else if (!strcmp((char *) loglevel_type,
1007                 config_loglevel_type_single)) {
1008                 ret = LTTNG_EVENT_LOGLEVEL_SINGLE;
1009         } else {
1010                 goto error;
1011         }
1012
1013         return ret;
1014 error:
1015         return -1;
1016 }
1017
1018 /*
1019  * Return the context type or -1 on error.
1020  */
1021 static
1022 int get_context_type(xmlChar *context_type)
1023 {
1024         int ret;
1025
1026         if (!context_type) {
1027                 goto error;
1028         }
1029
1030         if (!strcmp((char *) context_type, config_event_context_pid)) {
1031                 ret = LTTNG_EVENT_CONTEXT_PID;
1032         } else if (!strcmp((char *) context_type,
1033                 config_event_context_procname)) {
1034                 ret = LTTNG_EVENT_CONTEXT_PROCNAME;
1035         } else if (!strcmp((char *) context_type,
1036                 config_event_context_prio)) {
1037                 ret = LTTNG_EVENT_CONTEXT_PRIO;
1038         } else if (!strcmp((char *) context_type,
1039                 config_event_context_nice)) {
1040                 ret = LTTNG_EVENT_CONTEXT_NICE;
1041         } else if (!strcmp((char *) context_type,
1042                 config_event_context_vpid)) {
1043                 ret = LTTNG_EVENT_CONTEXT_VPID;
1044         } else if (!strcmp((char *) context_type,
1045                 config_event_context_tid)) {
1046                 ret = LTTNG_EVENT_CONTEXT_TID;
1047         } else if (!strcmp((char *) context_type,
1048                 config_event_context_vtid)) {
1049                 ret = LTTNG_EVENT_CONTEXT_VTID;
1050         } else if (!strcmp((char *) context_type,
1051                 config_event_context_ppid)) {
1052                 ret = LTTNG_EVENT_CONTEXT_PPID;
1053         } else if (!strcmp((char *) context_type,
1054                 config_event_context_vppid)) {
1055                 ret = LTTNG_EVENT_CONTEXT_VPPID;
1056         } else if (!strcmp((char *) context_type,
1057                 config_event_context_pthread_id)) {
1058                 ret = LTTNG_EVENT_CONTEXT_PTHREAD_ID;
1059         } else if (!strcmp((char *) context_type,
1060                 config_event_context_hostname)) {
1061                 ret = LTTNG_EVENT_CONTEXT_HOSTNAME;
1062         } else if (!strcmp((char *) context_type,
1063                 config_event_context_ip)) {
1064                 ret = LTTNG_EVENT_CONTEXT_IP;
1065         } else if (!strcmp((char *) context_type,
1066                 config_event_context_interruptible)) {
1067                 ret = LTTNG_EVENT_CONTEXT_INTERRUPTIBLE;
1068         } else if (!strcmp((char *) context_type,
1069                 config_event_context_preemptible)) {
1070                 ret = LTTNG_EVENT_CONTEXT_PREEMPTIBLE;
1071         } else if (!strcmp((char *) context_type,
1072                 config_event_context_need_reschedule)) {
1073                 ret = LTTNG_EVENT_CONTEXT_NEED_RESCHEDULE;
1074         } else if (!strcmp((char *) context_type,
1075                 config_event_context_migratable)) {
1076                 ret = LTTNG_EVENT_CONTEXT_MIGRATABLE;
1077         } else if (!strcmp((char *) context_type,
1078                 config_event_context_callstack_user)) {
1079                 ret = LTTNG_EVENT_CONTEXT_CALLSTACK_USER;
1080         } else if (!strcmp((char *) context_type,
1081                 config_event_context_callstack_kernel)) {
1082                 ret = LTTNG_EVENT_CONTEXT_CALLSTACK_KERNEL;
1083         } else if (!strcmp((char *) context_type,
1084                 config_event_context_cgroup_ns)) {
1085                 ret = LTTNG_EVENT_CONTEXT_CGROUP_NS;
1086         } else if (!strcmp((char *) context_type,
1087                 config_event_context_ipc_ns)) {
1088                 ret = LTTNG_EVENT_CONTEXT_IPC_NS;
1089         } else if (!strcmp((char *) context_type,
1090                 config_event_context_mnt_ns)) {
1091                 ret = LTTNG_EVENT_CONTEXT_MNT_NS;
1092         } else if (!strcmp((char *) context_type,
1093                 config_event_context_net_ns)) {
1094                 ret = LTTNG_EVENT_CONTEXT_NET_NS;
1095         } else if (!strcmp((char *) context_type,
1096                 config_event_context_pid_ns)) {
1097                 ret = LTTNG_EVENT_CONTEXT_PID_NS;
1098         } else if (!strcmp((char *) context_type,
1099                 config_event_context_time_ns)) {
1100                 ret = LTTNG_EVENT_CONTEXT_TIME_NS;
1101         } else if (!strcmp((char *) context_type,
1102                 config_event_context_user_ns)) {
1103                 ret = LTTNG_EVENT_CONTEXT_USER_NS;
1104         } else if (!strcmp((char *) context_type,
1105                 config_event_context_uts_ns)) {
1106                 ret = LTTNG_EVENT_CONTEXT_UTS_NS;
1107         } else if (!strcmp((char *) context_type,
1108                 config_event_context_uid)) {
1109                 ret = LTTNG_EVENT_CONTEXT_UID;
1110         } else if (!strcmp((char *) context_type,
1111                 config_event_context_euid)) {
1112                 ret = LTTNG_EVENT_CONTEXT_EUID;
1113         } else if (!strcmp((char *) context_type,
1114                 config_event_context_suid)) {
1115                 ret = LTTNG_EVENT_CONTEXT_SUID;
1116         } else if (!strcmp((char *) context_type,
1117                 config_event_context_gid)) {
1118                 ret = LTTNG_EVENT_CONTEXT_GID;
1119         } else if (!strcmp((char *) context_type,
1120                 config_event_context_egid)) {
1121                 ret = LTTNG_EVENT_CONTEXT_EGID;
1122         } else if (!strcmp((char *) context_type,
1123                 config_event_context_sgid)) {
1124                 ret = LTTNG_EVENT_CONTEXT_SGID;
1125         } else if (!strcmp((char *) context_type,
1126                 config_event_context_vuid)) {
1127                 ret = LTTNG_EVENT_CONTEXT_VUID;
1128         } else if (!strcmp((char *) context_type,
1129                 config_event_context_veuid)) {
1130                 ret = LTTNG_EVENT_CONTEXT_VEUID;
1131         } else if (!strcmp((char *) context_type,
1132                 config_event_context_vsuid)) {
1133                 ret = LTTNG_EVENT_CONTEXT_VSUID;
1134         } else if (!strcmp((char *) context_type,
1135                 config_event_context_vgid)) {
1136                 ret = LTTNG_EVENT_CONTEXT_VGID;
1137         } else if (!strcmp((char *) context_type,
1138                 config_event_context_vegid)) {
1139                 ret = LTTNG_EVENT_CONTEXT_VEGID;
1140         } else if (!strcmp((char *) context_type,
1141                 config_event_context_vsgid)) {
1142                 ret = LTTNG_EVENT_CONTEXT_VSGID;
1143         } else {
1144                 goto error;
1145         }
1146
1147         return ret;
1148 error:
1149         return -1;
1150 }
1151
1152 static
1153 int init_domain(xmlNodePtr domain_node, struct lttng_domain *domain)
1154 {
1155         int ret;
1156         xmlNodePtr node;
1157
1158         for (node = xmlFirstElementChild(domain_node); node;
1159                 node = xmlNextElementSibling(node)) {
1160                 if (!strcmp((const char *) node->name, config_element_type)) {
1161                         /* domain type */
1162                         xmlChar *node_content = xmlNodeGetContent(node);
1163                         if (!node_content) {
1164                                 ret = -LTTNG_ERR_NOMEM;
1165                                 goto end;
1166                         }
1167
1168                         ret = get_domain_type(node_content);
1169                         free(node_content);
1170                         if (ret < 0) {
1171                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
1172                                 goto end;
1173                         }
1174
1175                         domain->type = ret;
1176                 } else if (!strcmp((const char *) node->name,
1177                         config_element_buffer_type)) {
1178                         /* buffer type */
1179                         xmlChar *node_content = xmlNodeGetContent(node);
1180                         if (!node_content) {
1181                                 ret = -LTTNG_ERR_NOMEM;
1182                                 goto end;
1183                         }
1184
1185                         ret = get_buffer_type(node_content);
1186                         free(node_content);
1187                         if (ret < 0) {
1188                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
1189                                 goto end;
1190                         }
1191
1192                         domain->buf_type = ret;
1193                 }
1194         }
1195         ret = 0;
1196 end:
1197         return ret;
1198 }
1199
1200 static
1201 int get_net_output_uris(xmlNodePtr net_output_node, char **control_uri,
1202         char **data_uri)
1203 {
1204         xmlNodePtr node;
1205
1206         for (node = xmlFirstElementChild(net_output_node); node;
1207                 node = xmlNextElementSibling(node)) {
1208                 if (!strcmp((const char *) node->name, config_element_control_uri)) {
1209                         /* control_uri */
1210                         *control_uri = (char *) xmlNodeGetContent(node);
1211                         if (!*control_uri) {
1212                                 break;
1213                         }
1214                 } else {
1215                         /* data_uri */
1216                         *data_uri = (char *) xmlNodeGetContent(node);
1217                         if (!*data_uri) {
1218                                 break;
1219                         }
1220                 }
1221         }
1222
1223         return *control_uri || *data_uri ? 0 : -LTTNG_ERR_LOAD_INVALID_CONFIG;
1224 }
1225
1226 static
1227 int process_consumer_output(xmlNodePtr consumer_output_node,
1228         struct consumer_output *output)
1229 {
1230         int ret;
1231         xmlNodePtr node;
1232
1233         assert(output);
1234
1235         for (node = xmlFirstElementChild(consumer_output_node); node;
1236                         node = xmlNextElementSibling(node)) {
1237                 if (!strcmp((const char *) node->name, config_element_enabled)) {
1238                         xmlChar *enabled_str = xmlNodeGetContent(node);
1239
1240                         /* enabled */
1241                         if (!enabled_str) {
1242                                 ret = -LTTNG_ERR_NOMEM;
1243                                 goto end;
1244                         }
1245
1246                         ret = parse_bool(enabled_str, &output->enabled);
1247                         free(enabled_str);
1248                         if (ret) {
1249                                 goto end;
1250                         }
1251                 } else {
1252                         xmlNodePtr output_type_node;
1253
1254                         /* destination */
1255                         output_type_node = xmlFirstElementChild(node);
1256                         if (!output_type_node) {
1257                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
1258                                 goto end;
1259                         }
1260
1261                         if (!strcmp((const char *) output_type_node->name,
1262                                         config_element_path)) {
1263                                 /* path */
1264                                 output->path = (char *) xmlNodeGetContent(output_type_node);
1265                                 if (!output->path) {
1266                                         ret = -LTTNG_ERR_NOMEM;
1267                                         goto end;
1268                                 }
1269                         } else {
1270                                 /* net_output */
1271                                 ret = get_net_output_uris(output_type_node,
1272                                                 &output->control_uri, &output->data_uri);
1273                                 if (ret) {
1274                                         goto end;
1275                                 }
1276                         }
1277                 }
1278         }
1279         ret = 0;
1280
1281 end:
1282         if (ret) {
1283                 free(output->path);
1284                 free(output->control_uri);
1285                 free(output->data_uri);
1286                 memset(output, 0, sizeof(struct consumer_output));
1287         }
1288         return ret;
1289 }
1290
1291 static
1292 int create_session_net_output(const char *name, const char *control_uri,
1293                 const char *data_uri)
1294 {
1295         int ret;
1296         struct lttng_handle *handle;
1297         const char *uri = NULL;
1298
1299         assert(name);
1300
1301         handle = lttng_create_handle(name, NULL);
1302         if (!handle) {
1303                 ret = -LTTNG_ERR_NOMEM;
1304                 goto end;
1305         }
1306
1307         if (!control_uri || !data_uri) {
1308                 uri = control_uri ? control_uri : data_uri;
1309                 control_uri = uri;
1310                 data_uri = uri;
1311         }
1312
1313         ret = lttng_set_consumer_url(handle, control_uri, data_uri);
1314         lttng_destroy_handle(handle);
1315 end:
1316         return ret;
1317 }
1318
1319 static
1320 int create_snapshot_session(const char *session_name, xmlNodePtr output_node,
1321                 const struct config_load_session_override_attr *overrides)
1322 {
1323         int ret;
1324         xmlNodePtr node = NULL;
1325         xmlNodePtr snapshot_output_list_node;
1326         xmlNodePtr snapshot_output_node;
1327
1328         assert(session_name);
1329
1330         ret = lttng_create_session_snapshot(session_name, NULL);
1331         if (ret) {
1332                 goto end;
1333         }
1334
1335         if (!output_node) {
1336                 goto end;
1337         }
1338
1339         snapshot_output_list_node = xmlFirstElementChild(output_node);
1340
1341         /* Parse and create snapshot outputs */
1342
1343         for (snapshot_output_node =
1344                         xmlFirstElementChild(snapshot_output_list_node);
1345                         snapshot_output_node; snapshot_output_node =
1346                         xmlNextElementSibling(snapshot_output_node)) {
1347                 char *name = NULL;
1348                 uint64_t max_size = UINT64_MAX;
1349                 struct consumer_output output = { 0 };
1350                 struct lttng_snapshot_output *snapshot_output = NULL;
1351                 const char *control_uri = NULL;
1352                 const char *data_uri = NULL;
1353                 const char *path = NULL;
1354
1355                 for (node = xmlFirstElementChild(snapshot_output_node); node;
1356                                 node = xmlNextElementSibling(node)) {
1357                         if (!strcmp((const char *) node->name,
1358                                 config_element_name)) {
1359                                 /* name */
1360                                 name = (char *) xmlNodeGetContent(node);
1361                                 if (!name) {
1362                                         ret = -LTTNG_ERR_NOMEM;
1363                                         goto error_snapshot_output;
1364                                 }
1365                         } else if (!strcmp((const char *) node->name,
1366                                 config_element_max_size)) {
1367                                 xmlChar *content = xmlNodeGetContent(node);
1368
1369                                 /* max_size */
1370                                 if (!content) {
1371                                         ret = -LTTNG_ERR_NOMEM;
1372                                         goto error_snapshot_output;
1373                                 }
1374                                 ret = parse_uint(content, &max_size);
1375                                 free(content);
1376                                 if (ret) {
1377                                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
1378                                         goto error_snapshot_output;
1379                                 }
1380                         } else {
1381                                 /* consumer_output */
1382                                 ret = process_consumer_output(node, &output);
1383                                 if (ret) {
1384                                         goto error_snapshot_output;
1385                                 }
1386                         }
1387                 }
1388
1389                 control_uri = output.control_uri;
1390                 data_uri = output.data_uri;
1391                 path = output.path;
1392
1393                 if (overrides) {
1394                         if (overrides->path_url) {
1395                                 path = overrides->path_url;
1396                                 /* Control/data_uri are null */
1397                                 control_uri = NULL;
1398                                 data_uri = NULL;
1399                         } else {
1400                                 if (overrides->ctrl_url) {
1401                                         control_uri = overrides->ctrl_url;
1402                                         /* path is null */
1403                                         path = NULL;
1404                                 }
1405                                 if (overrides->data_url) {
1406                                         data_uri = overrides->data_url;
1407                                         /* path is null */
1408                                         path = NULL;
1409                                 }
1410                         }
1411                 }
1412
1413                 snapshot_output = lttng_snapshot_output_create();
1414                 if (!snapshot_output) {
1415                         ret = -LTTNG_ERR_NOMEM;
1416                         goto error_snapshot_output;
1417                 }
1418
1419                 ret = lttng_snapshot_output_set_name(name, snapshot_output);
1420                 if (ret) {
1421                         goto error_snapshot_output;
1422                 }
1423
1424                 ret = lttng_snapshot_output_set_size(max_size, snapshot_output);
1425                 if (ret) {
1426                         goto error_snapshot_output;
1427                 }
1428
1429                 if (path) {
1430                         ret = lttng_snapshot_output_set_ctrl_url(path,
1431                                         snapshot_output);
1432                         if (ret) {
1433                                 goto error_snapshot_output;
1434                         }
1435                 } else {
1436                         if (control_uri) {
1437                                 ret = lttng_snapshot_output_set_ctrl_url(control_uri,
1438                                                 snapshot_output);
1439                                 if (ret) {
1440                                         goto error_snapshot_output;
1441                                 }
1442                         }
1443
1444                         if (data_uri) {
1445                                 ret = lttng_snapshot_output_set_data_url(data_uri,
1446                                                 snapshot_output);
1447                                 if (ret) {
1448                                         goto error_snapshot_output;
1449                                 }
1450                         }
1451                 }
1452
1453                 ret = lttng_snapshot_add_output(session_name, snapshot_output);
1454 error_snapshot_output:
1455                 free(name);
1456                 free(output.path);
1457                 free(output.control_uri);
1458                 free(output.data_uri);
1459                 lttng_snapshot_output_destroy(snapshot_output);
1460                 if (ret) {
1461                         goto end;
1462                 }
1463         }
1464 end:
1465         return ret;
1466 }
1467
1468 static
1469 int create_session(const char *name,
1470         xmlNodePtr output_node,
1471         uint64_t live_timer_interval,
1472         const struct config_load_session_override_attr *overrides)
1473 {
1474         int ret;
1475         struct consumer_output output = { 0 };
1476         xmlNodePtr consumer_output_node;
1477         const char *control_uri = NULL;
1478         const char *data_uri = NULL;
1479         const char *path = NULL;
1480
1481         assert(name);
1482
1483         if (output_node) {
1484                 consumer_output_node = xmlFirstElementChild(output_node);
1485                 if (!consumer_output_node) {
1486                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
1487                         goto end;
1488                 }
1489
1490                 if (strcmp((const char *) consumer_output_node->name,
1491                         config_element_consumer_output)) {
1492                         WARN("Invalid output type, expected %s node",
1493                                 config_element_consumer_output);
1494                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
1495                         goto end;
1496                 }
1497
1498                 ret = process_consumer_output(consumer_output_node, &output);
1499                 if (ret) {
1500                         goto end;
1501                 }
1502         }
1503
1504         control_uri = output.control_uri;
1505         data_uri = output.data_uri;
1506         path = output.path;
1507
1508         /* Check for override and apply them */
1509         if (overrides) {
1510                 if (overrides->path_url) {
1511                         path = overrides->path_url;
1512                         /* control/data_uri are null */;
1513                         control_uri = NULL;
1514                         data_uri = NULL;
1515                 } else {
1516                         if (overrides->ctrl_url) {
1517                                 control_uri = overrides->ctrl_url;
1518                                 /* path is null */
1519                                 path = NULL;
1520                         }
1521                         if (overrides->data_url) {
1522                                 data_uri = overrides->data_url;
1523                                 /* path is null */
1524                                 path = NULL;
1525                         }
1526                 }
1527         }
1528
1529
1530         if (live_timer_interval != UINT64_MAX && !control_uri && !data_uri) {
1531                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
1532                 goto end;
1533         }
1534
1535         if (control_uri || data_uri) {
1536                 /* network destination */
1537                 if (live_timer_interval && live_timer_interval != UINT64_MAX) {
1538                         /*
1539                          * URLs are provided for sure since the test above make sure that
1540                          * with a live timer the data and control URIs are provided. So,
1541                          * NULL is passed here and will be set right after.
1542                          */
1543                         ret = lttng_create_session_live(name, NULL, live_timer_interval);
1544                 } else {
1545                         ret = lttng_create_session(name, NULL);
1546                 }
1547                 if (ret) {
1548                         goto end;
1549                 }
1550
1551                 ret = create_session_net_output(name, control_uri, data_uri);
1552                 if (ret) {
1553                         goto end;
1554                 }
1555
1556         } else {
1557                 /* either local output or no output */
1558                 ret = lttng_create_session(name, path);
1559                 if (ret) {
1560                         goto end;
1561                 }
1562         }
1563 end:
1564         free(output.path);
1565         free(output.control_uri);
1566         free(output.data_uri);
1567         return ret;
1568 }
1569
1570 static
1571 struct lttng_userspace_probe_location *
1572 process_userspace_probe_function_attribute_node(
1573                 xmlNodePtr attribute_node)
1574 {
1575         xmlNodePtr function_attribute_node;
1576         char *function_name = NULL, *binary_path = NULL;
1577         struct lttng_userspace_probe_location *location = NULL;
1578         struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL;
1579
1580         /*
1581          * Process userspace probe location function attributes. The order of
1582          * the fields are not guaranteed so we need to iterate over all fields
1583          * and check at the end if everything we need for this location type is
1584          * there.
1585          */
1586         for (function_attribute_node =
1587                         xmlFirstElementChild(attribute_node);
1588                         function_attribute_node;
1589                         function_attribute_node = xmlNextElementSibling(
1590                                 function_attribute_node)) {
1591                 /* Handle function name, binary path and lookup method. */
1592                 if (!strcmp((const char *) function_attribute_node->name,
1593                                         config_element_userspace_probe_function_location_function_name)) {
1594                         function_name = (char *) xmlNodeGetContent(function_attribute_node);
1595                         if (!function_name) {
1596                                 goto error;
1597                         }
1598                 } else if (!strcmp((const char *) function_attribute_node->name,
1599                                         config_element_userspace_probe_location_binary_path)) {
1600                         binary_path = (char *) xmlNodeGetContent(function_attribute_node);
1601                         if (!binary_path) {
1602                                 goto error;
1603                         }
1604                 } else if (!strcmp((const char *) function_attribute_node->name,
1605                                         config_element_userspace_probe_lookup)) {
1606                         char *lookup_method_name;
1607
1608                         lookup_method_name = (char *) xmlNodeGetContent(
1609                                         function_attribute_node);
1610                         if (!lookup_method_name) {
1611                                 goto error;
1612                         }
1613
1614                         /*
1615                          * function_default lookup method defaults to
1616                          * function_elf lookup method at the moment.
1617                          */
1618                         if (!strcmp(lookup_method_name, config_element_userspace_probe_lookup_function_elf)
1619                                         || !strcmp(lookup_method_name, config_element_userspace_probe_lookup_function_default)) {
1620                                 lookup_method = lttng_userspace_probe_location_lookup_method_function_elf_create();
1621                                 if (!lookup_method) {
1622                                         PERROR("Error creating function default/ELF lookup method");
1623                                 }
1624                         } else {
1625                                 WARN("Unknown function lookup method");
1626                         }
1627
1628                         free(lookup_method_name);
1629                         if (!lookup_method) {
1630                                 goto error;
1631                         }
1632                 } else {
1633                         goto error;
1634                 }
1635
1636                 /* Check if all the necessary fields were found. */
1637                 if (binary_path && function_name && lookup_method) {
1638                         /* Ownership of lookup_method is transferred. */
1639                         location =
1640                                 lttng_userspace_probe_location_function_create(
1641                                                 binary_path, function_name,
1642                                                 lookup_method);
1643                         lookup_method = NULL;
1644                         goto error;
1645                 }
1646         }
1647 error:
1648         lttng_userspace_probe_location_lookup_method_destroy(lookup_method);
1649         free(binary_path);
1650         free(function_name);
1651         return location;
1652 }
1653
1654 static
1655 struct lttng_userspace_probe_location *
1656 process_userspace_probe_tracepoint_attribute_node(
1657                 xmlNodePtr attribute_node)
1658 {
1659         xmlNodePtr tracepoint_attribute_node;
1660         char *probe_name = NULL, *provider_name = NULL, *binary_path = NULL;
1661         struct lttng_userspace_probe_location *location = NULL;
1662         struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL;
1663
1664         /*
1665          * Process userspace probe location tracepoint attributes. The order of
1666          * the fields are not guaranteed so we need to iterate over all fields
1667          * and check at the end if everything we need for this location type is
1668          * there.
1669          */
1670         for (tracepoint_attribute_node =
1671                 xmlFirstElementChild(attribute_node); tracepoint_attribute_node;
1672                 tracepoint_attribute_node = xmlNextElementSibling(
1673                                 tracepoint_attribute_node)) {
1674                 if (!strcmp((const char *) tracepoint_attribute_node->name,
1675                                         config_element_userspace_probe_tracepoint_location_probe_name)) {
1676                         probe_name = (char *) xmlNodeGetContent(tracepoint_attribute_node);
1677                         if (!probe_name) {
1678                                 goto error;
1679                         }
1680                 } else if (!strcmp((const char *) tracepoint_attribute_node->name,
1681                                         config_element_userspace_probe_tracepoint_location_provider_name)) {
1682                         provider_name = (char *) xmlNodeGetContent(tracepoint_attribute_node);
1683                         if (!provider_name) {
1684                                 goto error;
1685                         }
1686                 } else if (!strcmp((const char *) tracepoint_attribute_node->name,
1687                                         config_element_userspace_probe_location_binary_path)) {
1688                         binary_path = (char *) xmlNodeGetContent(tracepoint_attribute_node);
1689                         if (!binary_path) {
1690                                 goto error;
1691                         }
1692                 } else if (!strcmp((const char *) tracepoint_attribute_node->name,
1693                                         config_element_userspace_probe_lookup)) {
1694                         char *lookup_method_name;
1695
1696                         lookup_method_name = (char *) xmlNodeGetContent(
1697                                         tracepoint_attribute_node);
1698                         if (!lookup_method_name) {
1699                                 goto error;
1700                         }
1701
1702                         if (!strcmp(lookup_method_name,
1703                                                 config_element_userspace_probe_lookup_tracepoint_sdt)) {
1704                                 lookup_method =
1705                                         lttng_userspace_probe_location_lookup_method_tracepoint_sdt_create();
1706                                 if (!lookup_method) {
1707                                         PERROR("Error creating tracepoint SDT lookup method");
1708                                 }
1709                         } else {
1710                                 WARN("Unknown tracepoint lookup method");
1711                         }
1712
1713                         free(lookup_method_name);
1714                         if (!lookup_method) {
1715                                 goto error;
1716                         }
1717                 } else {
1718                         WARN("Unknown tracepoint attribute");
1719                         goto error;
1720                 }
1721
1722                 /* Check if all the necessary fields were found. */
1723                 if (binary_path && provider_name && probe_name && lookup_method) {
1724                         /* Ownership of lookup_method is transferred. */
1725                         location =
1726                                 lttng_userspace_probe_location_tracepoint_create(
1727                                                 binary_path, provider_name,
1728                                                 probe_name, lookup_method);
1729                         lookup_method = NULL;
1730                         goto error;
1731                 }
1732         }
1733 error:
1734         lttng_userspace_probe_location_lookup_method_destroy(lookup_method);
1735         free(binary_path);
1736         free(provider_name);
1737         free(probe_name);
1738         return location;
1739 }
1740
1741 static
1742 int process_probe_attribute_node(xmlNodePtr probe_attribute_node,
1743         struct lttng_event_probe_attr *attr)
1744 {
1745         int ret;
1746
1747         assert(probe_attribute_node);
1748         assert(attr);
1749
1750         if (!strcmp((const char *) probe_attribute_node->name,
1751                 config_element_address)) {
1752                 xmlChar *content;
1753                 uint64_t addr = 0;
1754
1755                 /* addr */
1756                 content = xmlNodeGetContent(probe_attribute_node);
1757                 if (!content) {
1758                         ret = -LTTNG_ERR_NOMEM;
1759                         goto end;
1760                 }
1761
1762                 ret = parse_uint(content, &addr);
1763                 free(content);
1764                 if (ret) {
1765                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
1766                         goto end;
1767                 }
1768
1769                 attr->addr = addr;
1770         } else if (!strcmp((const char *) probe_attribute_node->name,
1771                 config_element_offset)) {
1772                 xmlChar *content;
1773                 uint64_t offset = 0;
1774
1775                 /* offset */
1776                 content = xmlNodeGetContent(probe_attribute_node);
1777                 if (!content) {
1778                         ret = -LTTNG_ERR_NOMEM;
1779                         goto end;
1780                 }
1781
1782                 ret = parse_uint(content, &offset);
1783                 free(content);
1784                 if (ret) {
1785                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
1786                         goto end;
1787                 }
1788
1789                 attr->offset = offset;
1790         } else if (!strcmp((const char *) probe_attribute_node->name,
1791                 config_element_symbol_name)) {
1792                 xmlChar *content;
1793
1794                 /* symbol_name */
1795                 content = xmlNodeGetContent(probe_attribute_node);
1796                 if (!content) {
1797                         ret = -LTTNG_ERR_NOMEM;
1798                         goto end;
1799                 }
1800
1801                 ret = lttng_strncpy(attr->symbol_name,
1802                                 (const char *) content,
1803                                 LTTNG_SYMBOL_NAME_LEN);
1804                 if (ret == -1) {
1805                         ERR("symbol name \"%s\"'s length (%zu) exceeds the maximal permitted length (%d) in session configuration",
1806                                         (const char *) content,
1807                                         strlen((const char *) content),
1808                                         LTTNG_SYMBOL_NAME_LEN);
1809                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
1810                         free(content);
1811                         goto end;
1812                 }
1813                 free(content);
1814         }
1815         ret = 0;
1816 end:
1817         return ret;
1818 }
1819
1820 static
1821 int process_event_node(xmlNodePtr event_node, struct lttng_handle *handle,
1822         const char *channel_name, const enum process_event_node_phase phase)
1823 {
1824         int ret = 0, i;
1825         xmlNodePtr node;
1826         struct lttng_event *event;
1827         char **exclusions = NULL;
1828         unsigned long exclusion_count = 0;
1829         char *filter_expression = NULL;
1830
1831         assert(event_node);
1832         assert(handle);
1833         assert(channel_name);
1834
1835         event = lttng_event_create();
1836         if (!event) {
1837                 ret = -LTTNG_ERR_NOMEM;
1838                 goto end;
1839         }
1840
1841         /* Initialize default log level which varies by domain */
1842         switch (handle->domain.type)
1843         {
1844         case LTTNG_DOMAIN_JUL:
1845                 event->loglevel = LTTNG_LOGLEVEL_JUL_ALL;
1846                 break;
1847         case LTTNG_DOMAIN_LOG4J:
1848                 event->loglevel = LTTNG_LOGLEVEL_LOG4J_ALL;
1849                 break;
1850         case LTTNG_DOMAIN_PYTHON:
1851                 event->loglevel = LTTNG_LOGLEVEL_PYTHON_DEBUG;
1852                 break;
1853         case LTTNG_DOMAIN_UST:
1854         case LTTNG_DOMAIN_KERNEL:
1855                 event->loglevel = LTTNG_LOGLEVEL_DEBUG;
1856                 break;
1857         default:
1858                 assert(0);
1859         }
1860
1861         for (node = xmlFirstElementChild(event_node); node;
1862                 node = xmlNextElementSibling(node)) {
1863                 if (!strcmp((const char *) node->name, config_element_name)) {
1864                         xmlChar *content;
1865
1866                         /* name */
1867                         content = xmlNodeGetContent(node);
1868                         if (!content) {
1869                                 ret = -LTTNG_ERR_NOMEM;
1870                                 goto end;
1871                         }
1872
1873                         ret = lttng_strncpy(event->name,
1874                                         (const char *) content,
1875                                         LTTNG_SYMBOL_NAME_LEN);
1876                         if (ret == -1) {
1877                                 WARN("Event \"%s\"'s name length (%zu) exceeds the maximal permitted length (%d) in session configuration",
1878                                                 (const char *) content,
1879                                                 strlen((const char *) content),
1880                                                 LTTNG_SYMBOL_NAME_LEN);
1881                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
1882                                 free(content);
1883                                 goto end;
1884                         }
1885                         free(content);
1886                 } else if (!strcmp((const char *) node->name,
1887                         config_element_enabled)) {
1888                         xmlChar *content = xmlNodeGetContent(node);
1889
1890                         /* enabled */
1891                         if (!content) {
1892                                 ret = -LTTNG_ERR_NOMEM;
1893                                 goto end;
1894                         }
1895
1896                         ret = parse_bool(content, &event->enabled);
1897                         free(content);
1898                         if (ret) {
1899                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
1900                                 goto end;
1901                         }
1902                 } else if (!strcmp((const char *) node->name,
1903                         config_element_type)) {
1904                         xmlChar *content = xmlNodeGetContent(node);
1905
1906                         /* type */
1907                         if (!content) {
1908                                 ret = -LTTNG_ERR_NOMEM;
1909                                 goto end;
1910                         }
1911
1912                         ret = get_event_type(content);
1913                         free(content);
1914                         if (ret < 0) {
1915                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
1916                                 goto end;
1917                         }
1918
1919                         event->type = ret;
1920                 } else if (!strcmp((const char *) node->name,
1921                         config_element_loglevel_type)) {
1922                         xmlChar *content = xmlNodeGetContent(node);
1923
1924                         /* loglevel_type */
1925                         if (!content) {
1926                                 ret = -LTTNG_ERR_NOMEM;
1927                                 goto end;
1928                         }
1929
1930                         ret = get_loglevel_type(content);
1931                         free(content);
1932                         if (ret < 0) {
1933                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
1934                                 goto end;
1935                         }
1936
1937                         event->loglevel_type = ret;
1938                 } else if (!strcmp((const char *) node->name,
1939                         config_element_loglevel)) {
1940                         xmlChar *content;
1941                         int64_t loglevel = 0;
1942
1943                         /* loglevel */
1944                         content = xmlNodeGetContent(node);
1945                         if (!content) {
1946                                 ret = -LTTNG_ERR_NOMEM;
1947                                 goto end;
1948                         }
1949
1950                         ret = parse_int(content, &loglevel);
1951                         free(content);
1952                         if (ret) {
1953                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
1954                                 goto end;
1955                         }
1956
1957                         if (loglevel > INT_MAX || loglevel < INT_MIN) {
1958                                 WARN("loglevel out of range.");
1959                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
1960                                 goto end;
1961                         }
1962
1963                         event->loglevel = loglevel;
1964                 } else if (!strcmp((const char *) node->name,
1965                         config_element_filter)) {
1966                         xmlChar *content =
1967                                 xmlNodeGetContent(node);
1968
1969                         /* filter */
1970                         if (!content) {
1971                                 ret = -LTTNG_ERR_NOMEM;
1972                                 goto end;
1973                         }
1974
1975                         free(filter_expression);
1976                         filter_expression = strdup((char *) content);
1977                         free(content);
1978                         if (!filter_expression) {
1979                                 ret = -LTTNG_ERR_NOMEM;
1980                                 goto end;
1981                         }
1982                 } else if (!strcmp((const char *) node->name,
1983                         config_element_exclusions)) {
1984                         xmlNodePtr exclusion_node;
1985                         int exclusion_index = 0;
1986
1987                         /* exclusions */
1988                         if (exclusions) {
1989                                 /*
1990                                  * Exclusions has already been initialized,
1991                                  * invalid file.
1992                                  */
1993                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
1994                                 goto end;
1995                         }
1996
1997                         exclusion_count = xmlChildElementCount(node);
1998                         if (!exclusion_count) {
1999                                 continue;
2000                         }
2001
2002                         exclusions = zmalloc(exclusion_count * sizeof(char *));
2003                         if (!exclusions) {
2004                                 exclusion_count = 0;
2005                                 ret = -LTTNG_ERR_NOMEM;
2006                                 goto end;
2007                         }
2008
2009                         for (exclusion_node = xmlFirstElementChild(node); exclusion_node;
2010                                         exclusion_node = xmlNextElementSibling(exclusion_node)) {
2011                                 xmlChar *content =
2012                                         xmlNodeGetContent(exclusion_node);
2013
2014                                 if (!content) {
2015                                         ret = -LTTNG_ERR_NOMEM;
2016                                         goto end;
2017                                 }
2018
2019                                 exclusions[exclusion_index] = strdup((const char *) content);
2020                                 free(content);
2021                                 if (!exclusions[exclusion_index]) {
2022                                         ret = -LTTNG_ERR_NOMEM;
2023                                         goto end;
2024                                 }
2025                                 exclusion_index++;
2026                         }
2027
2028                         event->exclusion = 1;
2029                 } else if (!strcmp((const char *) node->name,
2030                         config_element_attributes)) {
2031                         xmlNodePtr attribute_node = xmlFirstElementChild(node);
2032
2033                         /* attributes */
2034                         if (!attribute_node) {
2035                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2036                                 goto end;
2037                         }
2038
2039                         if (!strcmp((const char *) attribute_node->name,
2040                                                 config_element_probe_attributes)) {
2041                                 xmlNodePtr probe_attribute_node;
2042
2043                                 /* probe_attributes */
2044                                 for (probe_attribute_node =
2045                                         xmlFirstElementChild(attribute_node); probe_attribute_node;
2046                                         probe_attribute_node = xmlNextElementSibling(
2047                                                         probe_attribute_node)) {
2048
2049                                         ret = process_probe_attribute_node(probe_attribute_node,
2050                                                         &event->attr.probe);
2051                                         if (ret) {
2052                                                 goto end;
2053                                         }
2054                                 }
2055                         } else if (!strcmp((const char *) attribute_node->name,
2056                                                 config_element_function_attributes)) {
2057                                 size_t sym_len;
2058                                 xmlChar *content;
2059                                 xmlNodePtr symbol_node = xmlFirstElementChild(attribute_node);
2060
2061                                 /* function_attributes */
2062                                 content = xmlNodeGetContent(symbol_node);
2063                                 if (!content) {
2064                                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2065                                         goto end;
2066                                 }
2067
2068                                 sym_len = strlen((char *) content);
2069                                 if (sym_len >= LTTNG_SYMBOL_NAME_LEN) {
2070                                         WARN("Function name too long.");
2071                                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2072                                         free(content);
2073                                         goto end;
2074                                 }
2075
2076                                 ret = lttng_strncpy(
2077                                                 event->attr.ftrace.symbol_name,
2078                                                 (char *) content, sym_len);
2079                                 if (ret == -1) {
2080                                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2081                                         free(content);
2082                                         goto end;
2083                                 }
2084                                 free(content);
2085                         } else if (!strcmp((const char *) attribute_node->name,
2086                                                 config_element_userspace_probe_tracepoint_attributes)) {
2087                                 struct lttng_userspace_probe_location *location;
2088
2089                                 location = process_userspace_probe_tracepoint_attribute_node(attribute_node);
2090                                 if (!location) {
2091                                         WARN("Error processing userspace probe tracepoint attribute");
2092                                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2093                                         goto end;
2094                                 }
2095                                 ret = lttng_event_set_userspace_probe_location(
2096                                                 event, location);
2097                                 if (ret) {
2098                                         WARN("Error setting userspace probe location field");
2099                                         lttng_userspace_probe_location_destroy(
2100                                                         location);
2101                                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2102                                         goto end;
2103                                 }
2104                         } else if (!strcmp((const char *) attribute_node->name,
2105                                                 config_element_userspace_probe_function_attributes)) {
2106                                 struct lttng_userspace_probe_location *location;
2107
2108                                 location =
2109                                         process_userspace_probe_function_attribute_node(
2110                                                         attribute_node);
2111                                 if (!location) {
2112                                         WARN("Error processing userspace probe function attribute");
2113                                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2114                                         goto end;
2115                                 }
2116
2117                                 ret = lttng_event_set_userspace_probe_location(
2118                                                 event, location);
2119                                 if (ret) {
2120                                         WARN("Error setting userspace probe location field");
2121                                         lttng_userspace_probe_location_destroy(
2122                                                         location);
2123                                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2124                                         goto end;
2125                                 }
2126                         } else {
2127                                 /* Unknown event attribute. */
2128                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2129                                 goto end;
2130                         }
2131                 }
2132         }
2133
2134         if ((event->enabled && phase == ENABLE) || phase == CREATION) {
2135                 ret = lttng_enable_event_with_exclusions(handle, event, channel_name,
2136                                 filter_expression, exclusion_count, exclusions);
2137                 if (ret < 0) {
2138                         WARN("Enabling event (name:%s) on load failed.", event->name);
2139                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2140                         goto end;
2141                 }
2142         }
2143         ret = 0;
2144 end:
2145         for (i = 0; i < exclusion_count; i++) {
2146                 free(exclusions[i]);
2147         }
2148
2149         lttng_event_destroy(event);
2150         free(exclusions);
2151         free(filter_expression);
2152         return ret;
2153 }
2154
2155 static
2156 int process_events_node(xmlNodePtr events_node, struct lttng_handle *handle,
2157         const char *channel_name)
2158 {
2159         int ret = 0;
2160         struct lttng_event event;
2161         xmlNodePtr node;
2162
2163         assert(events_node);
2164         assert(handle);
2165         assert(channel_name);
2166
2167         for (node = xmlFirstElementChild(events_node); node;
2168                 node = xmlNextElementSibling(node)) {
2169                 ret = process_event_node(node, handle, channel_name, CREATION);
2170                 if (ret) {
2171                         goto end;
2172                 }
2173         }
2174
2175         /*
2176          * Disable all events to enable only the necessary events.
2177          * Limitations regarding lttng_disable_events and tuple descriptor
2178          * force this approach.
2179          */
2180         memset(&event, 0, sizeof(event));
2181         event.loglevel = -1;
2182         event.type = LTTNG_EVENT_ALL;
2183         ret = lttng_disable_event_ext(handle, &event, channel_name, NULL);
2184         if (ret) {
2185                 goto end;
2186         }
2187
2188         for (node = xmlFirstElementChild(events_node); node;
2189                         node = xmlNextElementSibling(node)) {
2190                 ret = process_event_node(node, handle, channel_name, ENABLE);
2191                 if (ret) {
2192                         goto end;
2193                 }
2194         }
2195
2196 end:
2197         return ret;
2198 }
2199
2200 static
2201 int process_channel_attr_node(xmlNodePtr attr_node,
2202                 struct lttng_channel *channel, xmlNodePtr *contexts_node,
2203                 xmlNodePtr *events_node)
2204 {
2205         int ret;
2206
2207         assert(attr_node);
2208         assert(channel);
2209         assert(contexts_node);
2210         assert(events_node);
2211
2212         if (!strcmp((const char *) attr_node->name, config_element_name)) {
2213                 xmlChar *content;
2214
2215                 /* name */
2216                 content = xmlNodeGetContent(attr_node);
2217                 if (!content) {
2218                         ret = -LTTNG_ERR_NOMEM;
2219                         goto end;
2220                 }
2221
2222                 ret = lttng_strncpy(channel->name,
2223                                 (const char *) content,
2224                                 LTTNG_SYMBOL_NAME_LEN);
2225                 if (ret == -1) {
2226                         WARN("Channel \"%s\"'s name length (%zu) exceeds the maximal permitted length (%d) in session configuration",
2227                                         (const char *) content,
2228                                         strlen((const char *) content),
2229                                         LTTNG_SYMBOL_NAME_LEN);
2230                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2231                         free(content);
2232                         goto end;
2233                 }
2234                 free(content);
2235         } else if (!strcmp((const char *) attr_node->name,
2236                         config_element_enabled)) {
2237                 xmlChar *content;
2238                 int enabled;
2239
2240                 /* enabled */
2241                 content = xmlNodeGetContent(attr_node);
2242                 if (!content) {
2243                         ret = -LTTNG_ERR_NOMEM;
2244                         goto end;
2245                 }
2246
2247                 ret = parse_bool(content, &enabled);
2248                 free(content);
2249                 if (ret) {
2250                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2251                         goto end;
2252                 }
2253
2254                 channel->enabled = enabled;
2255         } else if (!strcmp((const char *) attr_node->name,
2256                         config_element_overwrite_mode)) {
2257                 xmlChar *content;
2258
2259                 /* overwrite_mode */
2260                 content = xmlNodeGetContent(attr_node);
2261                 if (!content) {
2262                         ret = -LTTNG_ERR_NOMEM;
2263                         goto end;
2264                 }
2265
2266                 ret = get_overwrite_mode(content);
2267                 free(content);
2268                 if (ret < 0) {
2269                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2270                         goto end;
2271                 }
2272
2273                 channel->attr.overwrite = ret;
2274         } else if (!strcmp((const char *) attr_node->name,
2275                         config_element_subbuf_size)) {
2276                 xmlChar *content;
2277
2278                 /* subbuffer_size */
2279                 content = xmlNodeGetContent(attr_node);
2280                 if (!content) {
2281                         ret = -LTTNG_ERR_NOMEM;
2282                         goto end;
2283                 }
2284
2285                 ret = parse_uint(content, &channel->attr.subbuf_size);
2286                 free(content);
2287                 if (ret) {
2288                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2289                         goto end;
2290                 }
2291         } else if (!strcmp((const char *) attr_node->name,
2292                         config_element_num_subbuf)) {
2293                 xmlChar *content;
2294
2295                 /* subbuffer_count */
2296                 content = xmlNodeGetContent(attr_node);
2297                 if (!content) {
2298                         ret = -LTTNG_ERR_NOMEM;
2299                         goto end;
2300                 }
2301
2302                 ret = parse_uint(content, &channel->attr.num_subbuf);
2303                 free(content);
2304                 if (ret) {
2305                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2306                         goto end;
2307                 }
2308         } else if (!strcmp((const char *) attr_node->name,
2309                         config_element_switch_timer_interval)) {
2310                 xmlChar *content;
2311                 uint64_t switch_timer_interval = 0;
2312
2313                 /* switch_timer_interval */
2314                 content = xmlNodeGetContent(attr_node);
2315                 if (!content) {
2316                         ret = -LTTNG_ERR_NOMEM;
2317                         goto end;
2318                 }
2319
2320                 ret = parse_uint(content, &switch_timer_interval);
2321                 free(content);
2322                 if (ret) {
2323                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2324                         goto end;
2325                 }
2326
2327                 if (switch_timer_interval > UINT_MAX) {
2328                         WARN("switch_timer_interval out of range.");
2329                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2330                         goto end;
2331                 }
2332
2333                 channel->attr.switch_timer_interval =
2334                         switch_timer_interval;
2335         } else if (!strcmp((const char *) attr_node->name,
2336                         config_element_read_timer_interval)) {
2337                 xmlChar *content;
2338                 uint64_t read_timer_interval = 0;
2339
2340                 /* read_timer_interval */
2341                 content = xmlNodeGetContent(attr_node);
2342                 if (!content) {
2343                         ret = -LTTNG_ERR_NOMEM;
2344                         goto end;
2345                 }
2346
2347                 ret = parse_uint(content, &read_timer_interval);
2348                 free(content);
2349                 if (ret) {
2350                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2351                         goto end;
2352                 }
2353
2354                 if (read_timer_interval > UINT_MAX) {
2355                         WARN("read_timer_interval out of range.");
2356                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2357                         goto end;
2358                 }
2359
2360                 channel->attr.read_timer_interval =
2361                         read_timer_interval;
2362         } else if (!strcmp((const char *) attr_node->name,
2363                         config_element_output_type)) {
2364                 xmlChar *content;
2365
2366                 /* output_type */
2367                 content = xmlNodeGetContent(attr_node);
2368                 if (!content) {
2369                         ret = -LTTNG_ERR_NOMEM;
2370                         goto end;
2371                 }
2372
2373                 ret = get_output_type(content);
2374                 free(content);
2375                 if (ret < 0) {
2376                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2377                         goto end;
2378                 }
2379
2380                 channel->attr.output = ret;
2381         } else if (!strcmp((const char *) attr_node->name,
2382                         config_element_tracefile_size)) {
2383                 xmlChar *content;
2384
2385                 /* tracefile_size */
2386                 content = xmlNodeGetContent(attr_node);
2387                 if (!content) {
2388                         ret = -LTTNG_ERR_NOMEM;
2389                         goto end;
2390                 }
2391
2392                 ret = parse_uint(content, &channel->attr.tracefile_size);
2393                 free(content);
2394                 if (ret) {
2395                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2396                         goto end;
2397                 }
2398         } else if (!strcmp((const char *) attr_node->name,
2399                         config_element_tracefile_count)) {
2400                 xmlChar *content;
2401
2402                 /* tracefile_count */
2403                 content = xmlNodeGetContent(attr_node);
2404                 if (!content) {
2405                         ret = -LTTNG_ERR_NOMEM;
2406                         goto end;
2407                 }
2408
2409                 ret = parse_uint(content, &channel->attr.tracefile_count);
2410                 free(content);
2411                 if (ret) {
2412                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2413                         goto end;
2414                 }
2415         } else if (!strcmp((const char *) attr_node->name,
2416                         config_element_live_timer_interval)) {
2417                 xmlChar *content;
2418                 uint64_t live_timer_interval = 0;
2419
2420                 /* live_timer_interval */
2421                 content = xmlNodeGetContent(attr_node);
2422                 if (!content) {
2423                         ret = -LTTNG_ERR_NOMEM;
2424                         goto end;
2425                 }
2426
2427                 ret = parse_uint(content, &live_timer_interval);
2428                 free(content);
2429                 if (ret) {
2430                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2431                         goto end;
2432                 }
2433
2434                 if (live_timer_interval > UINT_MAX) {
2435                         WARN("live_timer_interval out of range.");
2436                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2437                         goto end;
2438                 }
2439
2440                 channel->attr.live_timer_interval =
2441                         live_timer_interval;
2442         } else if (!strcmp((const char *) attr_node->name,
2443                         config_element_monitor_timer_interval)) {
2444                 xmlChar *content;
2445                 uint64_t monitor_timer_interval = 0;
2446
2447                 /* monitor_timer_interval */
2448                 content = xmlNodeGetContent(attr_node);
2449                 if (!content) {
2450                         ret = -LTTNG_ERR_NOMEM;
2451                         goto end;
2452                 }
2453
2454                 ret = parse_uint(content, &monitor_timer_interval);
2455                 free(content);
2456                 if (ret) {
2457                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2458                         goto end;
2459                 }
2460
2461                 ret = lttng_channel_set_monitor_timer_interval(channel,
2462                         monitor_timer_interval);
2463                 if (ret) {
2464                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2465                         goto end;
2466                 }
2467         } else if (!strcmp((const char *) attr_node->name,
2468                         config_element_blocking_timeout)) {
2469                 xmlChar *content;
2470                 int64_t blocking_timeout = 0;
2471
2472                 /* blocking_timeout */
2473                 content = xmlNodeGetContent(attr_node);
2474                 if (!content) {
2475                         ret = -LTTNG_ERR_NOMEM;
2476                         goto end;
2477                 }
2478
2479                 ret = parse_int(content, &blocking_timeout);
2480                 free(content);
2481                 if (ret) {
2482                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2483                         goto end;
2484                 }
2485
2486                 ret = lttng_channel_set_blocking_timeout(channel,
2487                         blocking_timeout);
2488                 if (ret) {
2489                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2490                         goto end;
2491                 }
2492         } else if (!strcmp((const char *) attr_node->name,
2493                         config_element_events)) {
2494                 /* events */
2495                 *events_node = attr_node;
2496         } else {
2497                 /* contexts */
2498                 *contexts_node = attr_node;
2499         }
2500         ret = 0;
2501 end:
2502         return ret;
2503 }
2504
2505 static
2506 int process_context_node(xmlNodePtr context_node,
2507         struct lttng_handle *handle, const char *channel_name)
2508 {
2509         int ret;
2510         struct lttng_event_context context;
2511         xmlNodePtr context_child_node = xmlFirstElementChild(context_node);
2512
2513         assert(handle);
2514         assert(channel_name);
2515
2516         if (!context_child_node) {
2517                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2518                 goto end;
2519         }
2520
2521         memset(&context, 0, sizeof(context));
2522
2523         if (!strcmp((const char *) context_child_node->name,
2524                 config_element_type)) {
2525                 /* type */
2526                 xmlChar *content = xmlNodeGetContent(context_child_node);
2527
2528                 if (!content) {
2529                         ret = -LTTNG_ERR_NOMEM;
2530                         goto end;
2531                 }
2532
2533                 ret = get_context_type(content);
2534                 free(content);
2535                 if (ret < 0) {
2536                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2537                         goto end;
2538                 }
2539
2540                 context.ctx = ret;
2541         } else if (!strcmp((const char *) context_child_node->name,
2542                 config_element_context_perf)) {
2543                 /* perf */
2544                 xmlNodePtr perf_attr_node;
2545
2546                 context.ctx = handle->domain.type == LTTNG_DOMAIN_KERNEL ?
2547                         LTTNG_EVENT_CONTEXT_PERF_CPU_COUNTER :
2548                         LTTNG_EVENT_CONTEXT_PERF_THREAD_COUNTER;
2549                 for (perf_attr_node = xmlFirstElementChild(context_child_node);
2550                         perf_attr_node; perf_attr_node =
2551                                 xmlNextElementSibling(perf_attr_node)) {
2552                         if (!strcmp((const char *) perf_attr_node->name,
2553                                 config_element_type)) {
2554                                 xmlChar *content;
2555                                 uint64_t type = 0;
2556
2557                                 /* type */
2558                                 content = xmlNodeGetContent(perf_attr_node);
2559                                 if (!content) {
2560                                         ret = -LTTNG_ERR_NOMEM;
2561                                         goto end;
2562                                 }
2563
2564                                 ret = parse_uint(content, &type);
2565                                 free(content);
2566                                 if (ret) {
2567                                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2568                                         goto end;
2569                                 }
2570
2571                                 if (type > UINT32_MAX) {
2572                                         WARN("perf context type out of range.");
2573                                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2574                                         goto end;
2575                                 }
2576
2577                                 context.u.perf_counter.type = type;
2578                         } else if (!strcmp((const char *) perf_attr_node->name,
2579                                 config_element_config)) {
2580                                 xmlChar *content;
2581                                 uint64_t config = 0;
2582
2583                                 /* config */
2584                                 content = xmlNodeGetContent(perf_attr_node);
2585                                 if (!content) {
2586                                         ret = -LTTNG_ERR_NOMEM;
2587                                         goto end;
2588                                 }
2589
2590                                 ret = parse_uint(content, &config);
2591                                 free(content);
2592                                 if (ret) {
2593                                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2594                                         goto end;
2595                                 }
2596
2597                                 context.u.perf_counter.config = config;
2598                         } else if (!strcmp((const char *) perf_attr_node->name,
2599                                 config_element_name)) {
2600                                 xmlChar *content;
2601
2602                                 /* name */
2603                                 content = xmlNodeGetContent(perf_attr_node);
2604                                 if (!content) {
2605                                         ret = -LTTNG_ERR_NOMEM;
2606                                         goto end;
2607                                 }
2608
2609                                 ret = lttng_strncpy(context.u.perf_counter.name,
2610                                                 (const char *) content,
2611                                                 LTTNG_SYMBOL_NAME_LEN);
2612                                 if (ret == -1) {
2613                                         WARN("Perf counter \"%s\"'s name length (%zu) exceeds the maximal permitted length (%d) in session configuration",
2614                                                         (const char *) content,
2615                                                         strlen((const char *) content),
2616                                                         LTTNG_SYMBOL_NAME_LEN);
2617                                         ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2618                                         free(content);
2619                                         goto end;
2620                                 }
2621                                 free(content);
2622                         }
2623                 }
2624         } else if (!strcmp((const char *) context_child_node->name,
2625                 config_element_context_app)) {
2626                 /* application context */
2627                 xmlNodePtr app_ctx_node;
2628
2629                 context.ctx = LTTNG_EVENT_CONTEXT_APP_CONTEXT;
2630                 for (app_ctx_node = xmlFirstElementChild(context_child_node);
2631                                 app_ctx_node; app_ctx_node =
2632                                 xmlNextElementSibling(app_ctx_node)) {
2633                         xmlChar *content;
2634                         char **target = strcmp(
2635                                 (const char *) app_ctx_node->name,
2636                                 config_element_context_app_provider_name) == 0 ?
2637                                         &context.u.app_ctx.provider_name :
2638                                         &context.u.app_ctx.ctx_name;
2639
2640                         content = xmlNodeGetContent(app_ctx_node);
2641                         if (!content) {
2642                                 ret = -LTTNG_ERR_NOMEM;
2643                                 goto end;
2644                         }
2645
2646                         *target = (char *) content;
2647                 }
2648         } else {
2649                 /* Unrecognized context type */
2650                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
2651                 goto end;
2652         }
2653
2654         ret = lttng_add_context(handle, &context, NULL, channel_name);
2655         if (context.ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
2656                 free(context.u.app_ctx.provider_name);
2657                 free(context.u.app_ctx.ctx_name);
2658         }
2659 end:
2660         return ret;
2661 }
2662
2663 static
2664 int process_contexts_node(xmlNodePtr contexts_node,
2665         struct lttng_handle *handle, const char *channel_name)
2666 {
2667         int ret = 0;
2668         xmlNodePtr context_node;
2669
2670         for (context_node = xmlFirstElementChild(contexts_node); context_node;
2671                         context_node = xmlNextElementSibling(context_node)) {
2672                 ret = process_context_node(context_node, handle, channel_name);
2673                 if (ret) {
2674                         goto end;
2675                 }
2676         }
2677 end:
2678         return ret;
2679 }
2680
2681 static int get_tracker_elements(enum lttng_process_attr process_attr,
2682                 const char **element_id_tracker,
2683                 const char **element_value_type,
2684                 const char **element_value,
2685                 const char **element_value_alias,
2686                 const char **element_name)
2687 {
2688         int ret = 0;
2689
2690         switch (process_attr) {
2691         case LTTNG_PROCESS_ATTR_PROCESS_ID:
2692                 *element_id_tracker = config_element_process_attr_tracker_pid;
2693                 *element_value_type = config_element_process_attr_pid_value;
2694                 *element_value = config_element_process_attr_id;
2695                 *element_value_alias = config_element_process_attr_id;
2696                 *element_name = NULL;
2697                 break;
2698         case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
2699                 *element_id_tracker = config_element_process_attr_tracker_vpid;
2700                 *element_value_type = config_element_process_attr_vpid_value;
2701                 *element_value = config_element_process_attr_id;
2702                 *element_value_alias = NULL;
2703                 *element_name = NULL;
2704                 break;
2705         case LTTNG_PROCESS_ATTR_USER_ID:
2706                 *element_id_tracker = config_element_process_attr_tracker_uid;
2707                 *element_value_type = config_element_process_attr_uid_value;
2708                 *element_value = config_element_process_attr_id;
2709                 *element_value_alias = NULL;
2710                 *element_name = config_element_name;
2711                 break;
2712         case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
2713                 *element_id_tracker = config_element_process_attr_tracker_vuid;
2714                 *element_value_type = config_element_process_attr_vuid_value;
2715                 *element_value = config_element_process_attr_id;
2716                 *element_value_alias = NULL;
2717                 *element_name = config_element_name;
2718                 break;
2719         case LTTNG_PROCESS_ATTR_GROUP_ID:
2720                 *element_id_tracker = config_element_process_attr_tracker_gid;
2721                 *element_value_type = config_element_process_attr_gid_value;
2722                 *element_value = config_element_process_attr_id;
2723                 *element_value_alias = NULL;
2724                 *element_name = config_element_name;
2725                 break;
2726         case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
2727                 *element_id_tracker = config_element_process_attr_tracker_vgid;
2728                 *element_value_type = config_element_process_attr_vgid_value;
2729                 *element_value = config_element_process_attr_id;
2730                 *element_value_alias = NULL;
2731                 *element_name = config_element_name;
2732                 break;
2733         default:
2734                 ret = LTTNG_ERR_INVALID;
2735         }
2736         return ret;
2737 }
2738
2739 static int process_legacy_pid_tracker_node(
2740                 xmlNodePtr trackers_node, struct lttng_handle *handle)
2741 {
2742         int ret = 0, child_count;
2743         xmlNodePtr targets_node = NULL;
2744         xmlNodePtr node;
2745         const char *element_id_tracker;
2746         const char *element_target_id;
2747         const char *element_id;
2748         const char *element_id_alias;
2749         const char *element_name;
2750         enum lttng_error_code tracker_handle_ret_code;
2751         struct lttng_process_attr_tracker_handle *tracker_handle = NULL;
2752         enum lttng_process_attr_tracker_handle_status status;
2753         const enum lttng_process_attr process_attr =
2754                         handle->domain.type == LTTNG_DOMAIN_UST ?
2755                                         LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID :
2756                                         LTTNG_PROCESS_ATTR_PROCESS_ID;
2757
2758         assert(handle);
2759
2760         tracker_handle_ret_code = lttng_session_get_tracker_handle(
2761                         handle->session_name, handle->domain.type,
2762                         process_attr,
2763                         &tracker_handle);
2764         if (tracker_handle_ret_code != LTTNG_OK) {
2765                 ret = LTTNG_ERR_INVALID;
2766                 goto end;
2767         }
2768
2769         ret = get_tracker_elements(process_attr, &element_id_tracker,
2770                         &element_target_id, &element_id, &element_id_alias,
2771                         &element_name);
2772         if (ret) {
2773                 goto end;
2774         }
2775
2776         /* Get the targets node */
2777         for (node = xmlFirstElementChild(trackers_node); node;
2778                         node = xmlNextElementSibling(node)) {
2779                 if (!strcmp((const char *) node->name,
2780                                 config_element_tracker_targets_legacy)) {
2781                         targets_node = node;
2782                         break;
2783                 }
2784         }
2785
2786         if (!targets_node) {
2787                 ret = LTTNG_ERR_INVALID;
2788                 goto end;
2789         }
2790
2791         /* Go through all id target node */
2792         child_count = xmlChildElementCount(targets_node);
2793         status = lttng_process_attr_tracker_handle_set_tracking_policy(
2794                         tracker_handle,
2795                         child_count == 0 ? LTTNG_TRACKING_POLICY_EXCLUDE_ALL :
2796                                            LTTNG_TRACKING_POLICY_INCLUDE_SET);
2797         if (status != LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_OK) {
2798                 ret = LTTNG_ERR_UNK;
2799                 goto end;
2800         }
2801
2802         /* Add all tracked values. */
2803         for (node = xmlFirstElementChild(targets_node); node;
2804                         node = xmlNextElementSibling(node)) {
2805                 xmlNodePtr pid_target_node = node;
2806
2807                 /* get pid_target node and track it */
2808                 for (node = xmlFirstElementChild(pid_target_node); node;
2809                                 node = xmlNextElementSibling(node)) {
2810                         if (!strcmp((const char *) node->name,
2811                                             config_element_tracker_pid_legacy)) {
2812                                 int64_t id;
2813                                 xmlChar *content = xmlNodeGetContent(node);
2814
2815                                 if (!content) {
2816                                         ret = LTTNG_ERR_LOAD_INVALID_CONFIG;
2817                                         goto end;
2818                                 }
2819
2820                                 ret = parse_int(content, &id);
2821                                 free(content);
2822                                 if (ret) {
2823                                         ret = LTTNG_ERR_LOAD_INVALID_CONFIG;
2824                                         goto end;
2825                                 }
2826
2827                                 switch (process_attr) {
2828                                 case LTTNG_PROCESS_ATTR_PROCESS_ID:
2829                                         status = lttng_process_attr_process_id_tracker_handle_add_pid(
2830                                                         tracker_handle,
2831                                                         (pid_t) id);
2832                                         break;
2833                                 case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
2834                                         status = lttng_process_attr_virtual_process_id_tracker_handle_add_pid(
2835                                                         tracker_handle,
2836                                                         (pid_t) id);
2837                                         break;
2838                                 default:
2839                                         ret = LTTNG_ERR_INVALID;
2840                                         goto end;
2841                                 }
2842                         }
2843                         switch (status) {
2844                         case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_OK:
2845                                 continue;
2846                         case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_INVALID:
2847                                 ret = LTTNG_ERR_INVALID;
2848                                 break;
2849                         case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_EXISTS:
2850                                 ret = LTTNG_ERR_PROCESS_ATTR_EXISTS;
2851                                 break;
2852                         case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_MISSING:
2853                                 ret = LTTNG_ERR_PROCESS_ATTR_MISSING;
2854                                 break;
2855                         case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_ERROR:
2856                         case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_COMMUNICATION_ERROR:
2857                         default:
2858                                 ret = LTTNG_ERR_UNK;
2859                                 goto end;
2860                         }
2861                 }
2862                 node = pid_target_node;
2863         }
2864
2865 end:
2866         lttng_process_attr_tracker_handle_destroy(tracker_handle);
2867         return ret;
2868  }
2869
2870 static int process_id_tracker_node(xmlNodePtr id_tracker_node,
2871                 struct lttng_handle *handle,
2872                 enum lttng_process_attr process_attr)
2873 {
2874         int ret = 0, child_count;
2875         xmlNodePtr values_node = NULL;
2876         xmlNodePtr node;
2877         const char *element_id_tracker;
2878         const char *element_target_id;
2879         const char *element_id;
2880         const char *element_id_alias;
2881         const char *element_name;
2882         enum lttng_error_code tracker_handle_ret_code;
2883         struct lttng_process_attr_tracker_handle *tracker_handle = NULL;
2884         enum lttng_process_attr_tracker_handle_status status;
2885
2886         assert(handle);
2887         assert(id_tracker_node);
2888
2889         tracker_handle_ret_code = lttng_session_get_tracker_handle(
2890                         handle->session_name, handle->domain.type, process_attr,
2891                         &tracker_handle);
2892         if (tracker_handle_ret_code != LTTNG_OK) {
2893                 ret = LTTNG_ERR_INVALID;
2894                 goto end;
2895         }
2896
2897         ret = get_tracker_elements(process_attr, &element_id_tracker,
2898                         &element_target_id, &element_id, &element_id_alias,
2899                         &element_name);
2900         if (ret) {
2901                 goto end;
2902         }
2903
2904         /* get the values node */
2905         for (node = xmlFirstElementChild(id_tracker_node); node;
2906                         node = xmlNextElementSibling(node)) {
2907                 if (!strcmp((const char *) node->name,
2908                                 config_element_process_attr_values)) {
2909                         values_node = node;
2910                         break;
2911                 }
2912         }
2913
2914         if (!values_node) {
2915                 ret = LTTNG_ERR_INVALID;
2916                 goto end;
2917         }
2918
2919         /* Go through all id target node */
2920         child_count = xmlChildElementCount(values_node);
2921         status = lttng_process_attr_tracker_handle_set_tracking_policy(
2922                         tracker_handle,
2923                         child_count == 0 ? LTTNG_TRACKING_POLICY_EXCLUDE_ALL :
2924                                            LTTNG_TRACKING_POLICY_INCLUDE_SET);
2925         if (status != LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_OK) {
2926                 ret = LTTNG_ERR_UNK;
2927                 goto end;
2928         }
2929
2930         /* Add all tracked values. */
2931         for (node = xmlFirstElementChild(values_node); node;
2932                         node = xmlNextElementSibling(node)) {
2933                 xmlNodePtr id_target_node = node;
2934
2935                 /* get id node and track it */
2936                 for (node = xmlFirstElementChild(id_target_node); node;
2937                                 node = xmlNextElementSibling(node)) {
2938                         if (!strcmp((const char *) node->name, element_id) ||
2939                                         (element_id_alias &&
2940                                                         !strcmp((const char *) node->name,
2941                                                                         element_id_alias))) {
2942                                 int64_t id;
2943                                 xmlChar *content = xmlNodeGetContent(node);
2944
2945                                 if (!content) {
2946                                         ret = LTTNG_ERR_LOAD_INVALID_CONFIG;
2947                                         goto end;
2948                                 }
2949
2950                                 ret = parse_int(content, &id);
2951                                 free(content);
2952                                 if (ret) {
2953                                         ret = LTTNG_ERR_LOAD_INVALID_CONFIG;
2954                                         goto end;
2955                                 }
2956
2957                                 switch (process_attr) {
2958                                 case LTTNG_PROCESS_ATTR_PROCESS_ID:
2959                                         status = lttng_process_attr_process_id_tracker_handle_add_pid(
2960                                                         tracker_handle,
2961                                                         (pid_t) id);
2962                                         break;
2963                                 case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
2964                                         status = lttng_process_attr_virtual_process_id_tracker_handle_add_pid(
2965                                                         tracker_handle,
2966                                                         (pid_t) id);
2967                                         break;
2968                                 case LTTNG_PROCESS_ATTR_USER_ID:
2969                                         status = lttng_process_attr_user_id_tracker_handle_add_uid(
2970                                                         tracker_handle,
2971                                                         (uid_t) id);
2972                                         break;
2973                                 case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
2974                                         status = lttng_process_attr_virtual_user_id_tracker_handle_add_uid(
2975                                                         tracker_handle,
2976                                                         (uid_t) id);
2977                                         break;
2978                                 case LTTNG_PROCESS_ATTR_GROUP_ID:
2979                                         status = lttng_process_attr_group_id_tracker_handle_add_gid(
2980                                                         tracker_handle,
2981                                                         (gid_t) id);
2982                                         break;
2983                                 case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
2984                                         status = lttng_process_attr_virtual_group_id_tracker_handle_add_gid(
2985                                                         tracker_handle,
2986                                                         (gid_t) id);
2987                                         break;
2988                                 default:
2989                                         ret = LTTNG_ERR_INVALID;
2990                                         goto end;
2991                                 }
2992                         } else if (element_name &&
2993                                         !strcmp((const char *) node->name,
2994                                                         element_name)) {
2995                                 xmlChar *content = xmlNodeGetContent(node);
2996
2997                                 if (!content) {
2998                                         ret = LTTNG_ERR_LOAD_INVALID_CONFIG;
2999                                         goto end;
3000                                 }
3001
3002                                 switch (process_attr) {
3003                                 case LTTNG_PROCESS_ATTR_USER_ID:
3004                                         status = lttng_process_attr_user_id_tracker_handle_add_user_name(
3005                                                         tracker_handle,
3006                                                         (const char *) content);
3007                                         break;
3008                                 case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
3009                                         status = lttng_process_attr_virtual_user_id_tracker_handle_add_user_name(
3010                                                         tracker_handle,
3011                                                         (const char *) content);
3012                                         break;
3013                                 case LTTNG_PROCESS_ATTR_GROUP_ID:
3014                                         status = lttng_process_attr_group_id_tracker_handle_add_group_name(
3015                                                         tracker_handle,
3016                                                         (const char *) content);
3017                                         break;
3018                                 case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
3019                                         status = lttng_process_attr_virtual_group_id_tracker_handle_add_group_name(
3020                                                         tracker_handle,
3021                                                         (const char *) content);
3022                                         break;
3023                                 default:
3024                                         free(content);
3025                                         ret = LTTNG_ERR_INVALID;
3026                                         goto end;
3027                                 }
3028                                 free(content);
3029                         }
3030                         switch (status) {
3031                         case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_OK:
3032                                 continue;
3033                         case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_INVALID:
3034                                 ret = LTTNG_ERR_INVALID;
3035                                 break;
3036                         case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_EXISTS:
3037                                 ret = LTTNG_ERR_PROCESS_ATTR_EXISTS;
3038                                 break;
3039                         case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_MISSING:
3040                                 ret = LTTNG_ERR_PROCESS_ATTR_MISSING;
3041                                 break;
3042                         case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_ERROR:
3043                         case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_COMMUNICATION_ERROR:
3044                         default:
3045                                 ret = LTTNG_ERR_UNK;
3046                                 goto end;
3047                         }
3048                 }
3049                 node = id_target_node;
3050         }
3051
3052 end:
3053         lttng_process_attr_tracker_handle_destroy(tracker_handle);
3054         return ret;
3055 }
3056
3057 static
3058 int process_domain_node(xmlNodePtr domain_node, const char *session_name)
3059 {
3060         int ret;
3061         struct lttng_domain domain = { 0 };
3062         struct lttng_handle *handle = NULL;
3063         struct lttng_channel *channel = NULL;
3064         xmlNodePtr channels_node = NULL;
3065         xmlNodePtr trackers_node = NULL;
3066         xmlNodePtr pid_tracker_node = NULL;
3067         xmlNodePtr vpid_tracker_node = NULL;
3068         xmlNodePtr uid_tracker_node = NULL;
3069         xmlNodePtr vuid_tracker_node = NULL;
3070         xmlNodePtr gid_tracker_node = NULL;
3071         xmlNodePtr vgid_tracker_node = NULL;
3072         xmlNodePtr node;
3073
3074         assert(session_name);
3075
3076         ret = init_domain(domain_node, &domain);
3077         if (ret) {
3078                 goto end;
3079         }
3080
3081         handle = lttng_create_handle(session_name, &domain);
3082         if (!handle) {
3083                 ret = -LTTNG_ERR_NOMEM;
3084                 goto end;
3085         }
3086
3087         /* get the channels node */
3088         for (node = xmlFirstElementChild(domain_node); node;
3089                 node = xmlNextElementSibling(node)) {
3090                 if (!strcmp((const char *) node->name,
3091                         config_element_channels)) {
3092                         channels_node = node;
3093                         break;
3094                 }
3095         }
3096
3097         if (!channels_node) {
3098                 goto end;
3099         }
3100
3101         /* create all channels */
3102         for (node = xmlFirstElementChild(channels_node); node;
3103                 node = xmlNextElementSibling(node)) {
3104                 const enum lttng_domain_type original_domain = domain.type;
3105                 xmlNodePtr contexts_node = NULL;
3106                 xmlNodePtr events_node = NULL;
3107                 xmlNodePtr channel_attr_node;
3108
3109                 /*
3110                  * Channels of the "agent" types cannot be created directly.
3111                  * They are meant to be created implicitly through the
3112                  * activation of events in their domain. However, a user
3113                  * can override the default channel configuration attributes
3114                  * by creating the underlying UST channel _before_ enabling
3115                  * an agent domain event.
3116                  *
3117                  * Hence, the channel's type is substituted before the creation
3118                  * and restored by the time the events are created.
3119                  */
3120                 switch (domain.type) {
3121                 case LTTNG_DOMAIN_JUL:
3122                 case LTTNG_DOMAIN_LOG4J:
3123                 case LTTNG_DOMAIN_PYTHON:
3124                         domain.type = LTTNG_DOMAIN_UST;
3125                 default:
3126                         break;
3127                 }
3128
3129                 channel = lttng_channel_create(&domain);
3130                 if (!channel) {
3131                         ret = -1;
3132                         goto end;
3133                 }
3134
3135                 for (channel_attr_node = xmlFirstElementChild(node);
3136                         channel_attr_node; channel_attr_node =
3137                         xmlNextElementSibling(channel_attr_node)) {
3138                         ret = process_channel_attr_node(channel_attr_node,
3139                                 channel, &contexts_node, &events_node);
3140                         if (ret) {
3141                                 goto end;
3142                         }
3143                 }
3144
3145                 ret = lttng_enable_channel(handle, channel);
3146                 if (ret < 0) {
3147                         goto end;
3148                 }
3149
3150                 /* Restore the original channel domain. */
3151                 domain.type = original_domain;
3152
3153                 ret = process_events_node(events_node, handle, channel->name);
3154                 if (ret) {
3155                         goto end;
3156                 }
3157
3158                 ret = process_contexts_node(contexts_node, handle,
3159                         channel->name);
3160                 if (ret) {
3161                         goto end;
3162                 }
3163
3164                 lttng_channel_destroy(channel);
3165         }
3166         channel = NULL;
3167
3168         /* get the trackers node */
3169         for (node = xmlFirstElementChild(domain_node); node;
3170                         node = xmlNextElementSibling(node)) {
3171                 if (!strcmp((const char *) node->name,
3172                                     config_element_process_attr_trackers) ||
3173                                 !strcmp((const char *) node->name,
3174                                                 config_element_trackers_legacy)) {
3175                         if (trackers_node) {
3176                                 ERR("Only one instance of `%s` or `%s` is allowed in a session configuration",
3177                                                 config_element_process_attr_trackers,
3178                                                 config_element_trackers_legacy);
3179                                 ret = -1;
3180                                 goto end;
3181                         }
3182                         trackers_node = node;
3183                         break;
3184                 }
3185         }
3186
3187         if (!trackers_node) {
3188                 goto end;
3189         }
3190
3191         for (node = xmlFirstElementChild(trackers_node); node;
3192                         node = xmlNextElementSibling(node)) {
3193                 if (!strcmp((const char *) node->name,
3194                                     config_element_process_attr_tracker_pid)) {
3195                         pid_tracker_node = node;
3196                         ret = process_id_tracker_node(pid_tracker_node, handle,
3197                                         LTTNG_PROCESS_ATTR_PROCESS_ID);
3198                         if (ret) {
3199                                 goto end;
3200                         }
3201                 }
3202                 if (!strcmp((const char *) node->name,
3203                                     config_element_process_attr_tracker_vpid)) {
3204                         vpid_tracker_node = node;
3205                         ret = process_id_tracker_node(vpid_tracker_node, handle,
3206                                         LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID);
3207                         if (ret) {
3208                                 goto end;
3209                         }
3210                 }
3211                 if (!strcmp((const char *) node->name,
3212                                     config_element_process_attr_tracker_uid)) {
3213                         uid_tracker_node = node;
3214                         ret = process_id_tracker_node(uid_tracker_node, handle,
3215                                         LTTNG_PROCESS_ATTR_USER_ID);
3216                         if (ret) {
3217                                 goto end;
3218                         }
3219                 }
3220                 if (!strcmp((const char *) node->name,
3221                                     config_element_process_attr_tracker_vuid)) {
3222                         vuid_tracker_node = node;
3223                         ret = process_id_tracker_node(vuid_tracker_node, handle,
3224                                         LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID);
3225                         if (ret) {
3226                                 goto end;
3227                         }
3228                 }
3229                 if (!strcmp((const char *) node->name,
3230                                     config_element_process_attr_tracker_gid)) {
3231                         gid_tracker_node = node;
3232                         ret = process_id_tracker_node(gid_tracker_node, handle,
3233                                         LTTNG_PROCESS_ATTR_GROUP_ID);
3234                         if (ret) {
3235                                 goto end;
3236                         }
3237                 }
3238                 if (!strcmp((const char *) node->name,
3239                                     config_element_process_attr_tracker_vgid)) {
3240                         vgid_tracker_node = node;
3241                         ret = process_id_tracker_node(vgid_tracker_node, handle,
3242                                         LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID);
3243                         if (ret) {
3244                                 goto end;
3245                         }
3246                 }
3247                 if (!strcmp((const char *) node->name,
3248                                     config_element_pid_tracker_legacy)) {
3249                         ret = process_legacy_pid_tracker_node(node, handle);
3250                         if (ret) {
3251                                 goto end;
3252                         }
3253                 }
3254         }
3255
3256 end:
3257         lttng_channel_destroy(channel);
3258         lttng_destroy_handle(handle);
3259         return ret;
3260 }
3261
3262 static
3263 int add_periodic_rotation(const char *name, uint64_t time_us)
3264 {
3265         int ret;
3266         enum lttng_rotation_status status;
3267         struct lttng_rotation_schedule *periodic =
3268                         lttng_rotation_schedule_periodic_create();
3269
3270         if (!periodic) {
3271                 ret = -LTTNG_ERR_NOMEM;
3272                 goto error;
3273         }
3274
3275         status = lttng_rotation_schedule_periodic_set_period(periodic,
3276                         time_us);
3277         if (status != LTTNG_ROTATION_STATUS_OK) {
3278                 ret = -LTTNG_ERR_INVALID;
3279                 goto error;
3280         }
3281
3282         status = lttng_session_add_rotation_schedule(name, periodic);
3283         switch (status) {
3284         case LTTNG_ROTATION_STATUS_OK:
3285                 ret = 0;
3286                 break;
3287         case LTTNG_ROTATION_STATUS_SCHEDULE_ALREADY_SET:
3288         case LTTNG_ROTATION_STATUS_INVALID:
3289                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
3290                 break;
3291         default:
3292                 ret = -LTTNG_ERR_UNK;
3293                 break;
3294         }
3295 error:
3296         lttng_rotation_schedule_destroy(periodic);
3297         return ret;
3298 }
3299
3300 static
3301 int add_size_rotation(const char *name, uint64_t size_bytes)
3302 {
3303         int ret;
3304         enum lttng_rotation_status status;
3305         struct lttng_rotation_schedule *size =
3306                         lttng_rotation_schedule_size_threshold_create();
3307
3308         if (!size) {
3309                 ret = -LTTNG_ERR_NOMEM;
3310                 goto error;
3311         }
3312
3313         status = lttng_rotation_schedule_size_threshold_set_threshold(size,
3314                         size_bytes);
3315         if (status != LTTNG_ROTATION_STATUS_OK) {
3316                 ret = -LTTNG_ERR_INVALID;
3317                 goto error;
3318         }
3319
3320         status = lttng_session_add_rotation_schedule(name, size);
3321         switch (status) {
3322         case LTTNG_ROTATION_STATUS_OK:
3323                 ret = 0;
3324                 break;
3325         case LTTNG_ROTATION_STATUS_SCHEDULE_ALREADY_SET:
3326         case LTTNG_ROTATION_STATUS_INVALID:
3327                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
3328                 break;
3329         default:
3330                 ret = -LTTNG_ERR_UNK;
3331                 break;
3332         }
3333 error:
3334         lttng_rotation_schedule_destroy(size);
3335         return ret;
3336 }
3337
3338 static
3339 int process_session_rotation_schedules_node(
3340                 xmlNodePtr schedules_node,
3341                 uint64_t *rotation_timer_interval,
3342                 uint64_t *rotation_size)
3343 {
3344         int ret = 0;
3345         xmlNodePtr child;
3346
3347         for (child = xmlFirstElementChild(schedules_node);
3348                         child;
3349                         child = xmlNextElementSibling(child)) {
3350                 if (!strcmp((const char *) child->name,
3351                                 config_element_rotation_schedule_periodic)) {
3352                         xmlChar *content;
3353                         xmlNodePtr time_us_node;
3354
3355                         /* periodic rotation schedule */
3356                         time_us_node = xmlFirstElementChild(child);
3357                         if (!time_us_node ||
3358                                         strcmp((const char *) time_us_node->name,
3359                                                 config_element_rotation_schedule_periodic_time_us)) {
3360                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
3361                                 goto end;
3362                         }
3363
3364                         /* time_us child */
3365                         content = xmlNodeGetContent(time_us_node);
3366                         if (!content) {
3367                                 ret = -LTTNG_ERR_NOMEM;
3368                                 goto end;
3369                         }
3370                         ret = parse_uint(content, rotation_timer_interval);
3371                         free(content);
3372                         if (ret) {
3373                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
3374                                 goto end;
3375                         }
3376                 } else if (!strcmp((const char *) child->name,
3377                                 config_element_rotation_schedule_size_threshold)) {
3378                         xmlChar *content;
3379                         xmlNodePtr bytes_node;
3380
3381                         /* size_threshold rotation schedule */
3382                         bytes_node = xmlFirstElementChild(child);
3383                         if (!bytes_node ||
3384                                         strcmp((const char *) bytes_node->name,
3385                                                 config_element_rotation_schedule_size_threshold_bytes)) {
3386                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
3387                                 goto end;
3388                         }
3389
3390                         /* bytes child */
3391                         content = xmlNodeGetContent(bytes_node);
3392                         if (!content) {
3393                                 ret = -LTTNG_ERR_NOMEM;
3394                                 goto end;
3395                         }
3396                         ret = parse_uint(content, rotation_size);
3397                         free(content);
3398                         if (ret) {
3399                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
3400                                 goto end;
3401                         }
3402                 }
3403         }
3404
3405 end:
3406         return ret;
3407 }
3408
3409 static
3410 int process_session_node(xmlNodePtr session_node, const char *session_name,
3411                 int overwrite,
3412                 const struct config_load_session_override_attr *overrides)
3413 {
3414         int ret, started = -1, snapshot_mode = -1;
3415         uint64_t live_timer_interval = UINT64_MAX,
3416                          rotation_timer_interval = 0,
3417                          rotation_size = 0;
3418         xmlChar *name = NULL;
3419         xmlChar *shm_path = NULL;
3420         xmlNodePtr domains_node = NULL;
3421         xmlNodePtr output_node = NULL;
3422         xmlNodePtr node;
3423         xmlNodePtr attributes_child;
3424         struct lttng_domain *kernel_domain = NULL;
3425         struct lttng_domain *ust_domain = NULL;
3426         struct lttng_domain *jul_domain = NULL;
3427         struct lttng_domain *log4j_domain = NULL;
3428         struct lttng_domain *python_domain = NULL;
3429
3430         for (node = xmlFirstElementChild(session_node); node;
3431                 node = xmlNextElementSibling(node)) {
3432                 if (!name && !strcmp((const char *) node->name,
3433                         config_element_name)) {
3434                         /* name */
3435                         xmlChar *node_content = xmlNodeGetContent(node);
3436                         if (!node_content) {
3437                                 ret = -LTTNG_ERR_NOMEM;
3438                                 goto error;
3439                         }
3440
3441                         name = node_content;
3442                 } else if (!domains_node && !strcmp((const char *) node->name,
3443                         config_element_domains)) {
3444                         /* domains */
3445                         domains_node = node;
3446                 } else if (started == -1 && !strcmp((const char *) node->name,
3447                         config_element_started)) {
3448                         /* started */
3449                         xmlChar *node_content = xmlNodeGetContent(node);
3450                         if (!node_content) {
3451                                 ret = -LTTNG_ERR_NOMEM;
3452                                 goto error;
3453                         }
3454
3455                         ret = parse_bool(node_content, &started);
3456                         free(node_content);
3457                         if (ret) {
3458                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
3459                                 goto error;
3460                         }
3461                 } else if (!output_node && !strcmp((const char *) node->name,
3462                         config_element_output)) {
3463                         /* output */
3464                         output_node = node;
3465                 } else if (!shm_path && !strcmp((const char *) node->name,
3466                         config_element_shared_memory_path)) {
3467                         /* shared memory path */
3468                         xmlChar *node_content = xmlNodeGetContent(node);
3469                         if (!node_content) {
3470                                 ret = -LTTNG_ERR_NOMEM;
3471                                 goto error;
3472                         }
3473
3474                         shm_path = node_content;
3475                 } else {
3476                         /*
3477                          * attributes, snapshot_mode, live_timer_interval, rotation_size,
3478                          * rotation_timer_interval.
3479                          */
3480                         for (attributes_child = xmlFirstElementChild(node); attributes_child;
3481                                         attributes_child = xmlNextElementSibling(attributes_child)) {
3482                                 if (!strcmp((const char *) attributes_child->name,
3483                                                         config_element_snapshot_mode)) {
3484                                         /* snapshot_mode */
3485                                         xmlChar *snapshot_mode_content =
3486                                                 xmlNodeGetContent(attributes_child);
3487                                         if (!snapshot_mode_content) {
3488                                                 ret = -LTTNG_ERR_NOMEM;
3489                                                 goto error;
3490                                         }
3491
3492                                         ret = parse_bool(snapshot_mode_content, &snapshot_mode);
3493                                         free(snapshot_mode_content);
3494                                         if (ret) {
3495                                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
3496                                                 goto error;
3497                                         }
3498                                 } else if (!strcmp((const char *) attributes_child->name,
3499                                                         config_element_live_timer_interval)) {
3500                                         /* live_timer_interval */
3501                                         xmlChar *timer_interval_content =
3502                                                 xmlNodeGetContent(attributes_child);
3503                                         if (!timer_interval_content) {
3504                                                 ret = -LTTNG_ERR_NOMEM;
3505                                                 goto error;
3506                                         }
3507
3508                                         ret = parse_uint(timer_interval_content, &live_timer_interval);
3509                                         free(timer_interval_content);
3510                                         if (ret) {
3511                                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
3512                                                 goto error;
3513                                         }
3514                                 } else if (!strcmp((const char *) attributes_child->name,
3515                                                         config_element_rotation_schedules)) {
3516                                         ret = process_session_rotation_schedules_node(
3517                                                         attributes_child,
3518                                                         &rotation_timer_interval,
3519                                                         &rotation_size);
3520                                         if (ret) {
3521                                                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
3522                                                 goto error;
3523                                         }
3524
3525                                 }
3526                         }
3527                 }
3528         }
3529
3530         if (!name) {
3531                 /* Mandatory attribute, as defined in the session XSD */
3532                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
3533                 goto error;
3534         }
3535
3536         if (session_name && strcmp((char *) name, session_name)) {
3537                 /* This is not the session we are looking for */
3538                 ret = -LTTNG_ERR_NO_SESSION;
3539                 goto error;
3540         }
3541
3542         /* Init domains to create the session handles */
3543         for (node = xmlFirstElementChild(domains_node); node;
3544                 node = xmlNextElementSibling(node)) {
3545                 struct lttng_domain *domain;
3546
3547                 domain = zmalloc(sizeof(*domain));
3548                 if (!domain) {
3549                         ret = -LTTNG_ERR_NOMEM;
3550                         goto error;
3551                 }
3552
3553                 ret = init_domain(node, domain);
3554                 if (ret) {
3555                         goto domain_init_error;
3556                 }
3557
3558                 switch (domain->type) {
3559                 case LTTNG_DOMAIN_KERNEL:
3560                         if (kernel_domain) {
3561                                 /* Same domain seen twice, invalid! */
3562                                 goto domain_init_error;
3563                         }
3564                         kernel_domain = domain;
3565                         break;
3566                 case LTTNG_DOMAIN_UST:
3567                         if (ust_domain) {
3568                                 /* Same domain seen twice, invalid! */
3569                                 goto domain_init_error;
3570                         }
3571                         ust_domain = domain;
3572                         break;
3573                 case LTTNG_DOMAIN_JUL:
3574                         if (jul_domain) {
3575                                 /* Same domain seen twice, invalid! */
3576                                 goto domain_init_error;
3577                         }
3578                         jul_domain = domain;
3579                         break;
3580                 case LTTNG_DOMAIN_LOG4J:
3581                         if (log4j_domain) {
3582                                 /* Same domain seen twice, invalid! */
3583                                 goto domain_init_error;
3584                         }
3585                         log4j_domain = domain;
3586                         break;
3587                 case LTTNG_DOMAIN_PYTHON:
3588                         if (python_domain) {
3589                                 /* Same domain seen twice, invalid! */
3590                                 goto domain_init_error;
3591                         }
3592                         python_domain = domain;
3593                         break;
3594                 default:
3595                         WARN("Invalid domain type");
3596                         goto domain_init_error;
3597                 }
3598                 continue;
3599 domain_init_error:
3600                 free(domain);
3601                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
3602                 goto error;
3603         }
3604
3605         /* Apply overrides */
3606         if (overrides) {
3607                 if (overrides->session_name) {
3608                         xmlChar *name_override = xmlStrdup(BAD_CAST(overrides->session_name));
3609                         if (!name_override) {
3610                                 ret = -LTTNG_ERR_NOMEM;
3611                                 goto error;
3612                         }
3613
3614                         /* Overrides the session name to the provided name */
3615                         xmlFree(name);
3616                         name = name_override;
3617                 }
3618         }
3619
3620         if (overwrite) {
3621                 /* Destroy session if it exists */
3622                 ret = lttng_destroy_session((const char *) name);
3623                 if (ret && ret != -LTTNG_ERR_SESS_NOT_FOUND) {
3624                         ERR("Failed to destroy existing session.");
3625                         goto error;
3626                 }
3627         }
3628
3629         /* Create session type depending on output type */
3630         if (snapshot_mode && snapshot_mode != -1) {
3631                 ret = create_snapshot_session((const char *) name, output_node,
3632                                 overrides);
3633         } else if (live_timer_interval &&
3634                 live_timer_interval != UINT64_MAX) {
3635                 ret = create_session((const char *) name,
3636                                 output_node, live_timer_interval, overrides);
3637         } else {
3638                 /* regular session */
3639                 ret = create_session((const char *) name,
3640                                 output_node, UINT64_MAX, overrides);
3641         }
3642         if (ret) {
3643                 goto error;
3644         }
3645
3646         if (shm_path) {
3647                 ret = lttng_set_session_shm_path((const char *) name,
3648                                 (const char *) shm_path);
3649                 if (ret) {
3650                         goto error;
3651                 }
3652         }
3653
3654         for (node = xmlFirstElementChild(domains_node); node;
3655                 node = xmlNextElementSibling(node)) {
3656                 ret = process_domain_node(node, (const char *) name);
3657                 if (ret) {
3658                         goto end;
3659                 }
3660         }
3661
3662         if (rotation_timer_interval) {
3663                 ret = add_periodic_rotation((const char *) name,
3664                                 rotation_timer_interval);
3665                 if (ret < 0) {
3666                         goto error;
3667                 }
3668         }
3669         if (rotation_size) {
3670                 ret = add_size_rotation((const char *) name,
3671                                 rotation_size);
3672                 if (ret < 0) {
3673                         goto error;
3674                 }
3675         }
3676
3677         if (started) {
3678                 ret = lttng_start_tracing((const char *) name);
3679                 if (ret) {
3680                         goto end;
3681                 }
3682         }
3683
3684 end:
3685         if (ret < 0) {
3686                 ERR("Failed to load session %s: %s", (const char *) name,
3687                         lttng_strerror(ret));
3688                 lttng_destroy_session((const char *) name);
3689         }
3690
3691 error:
3692         free(kernel_domain);
3693         free(ust_domain);
3694         free(jul_domain);
3695         free(log4j_domain);
3696         free(python_domain);
3697         xmlFree(name);
3698         xmlFree(shm_path);
3699         return ret;
3700 }
3701
3702 /*
3703  * Return 1 if the given path is readable by the current UID or 0 if not.
3704  * Return -1 if the path is EPERM.
3705  */
3706 static int validate_file_read_creds(const char *path)
3707 {
3708         int ret;
3709
3710         assert(path);
3711
3712         /* Can we read the file. */
3713         ret = access(path, R_OK);
3714         if (!ret) {
3715                 goto valid;
3716         }
3717         if (errno == EACCES) {
3718                 return -1;
3719         } else {
3720                 /* Invalid. */
3721                 return 0;
3722         }
3723 valid:
3724         return 1;
3725 }
3726
3727 static
3728 int load_session_from_file(const char *path, const char *session_name,
3729         struct session_config_validation_ctx *validation_ctx, int overwrite,
3730         const struct config_load_session_override_attr *overrides)
3731 {
3732         int ret, session_found = !session_name;
3733         xmlDocPtr doc = NULL;
3734         xmlNodePtr sessions_node;
3735         xmlNodePtr session_node;
3736
3737         assert(path);
3738         assert(validation_ctx);
3739
3740         ret = validate_file_read_creds(path);
3741         if (ret != 1) {
3742                 if (ret == -1) {
3743                         ret = -LTTNG_ERR_EPERM;
3744                 } else {
3745                         ret = -LTTNG_ERR_LOAD_SESSION_NOENT;
3746                 }
3747                 goto end;
3748         }
3749
3750         doc = xmlParseFile(path);
3751         if (!doc) {
3752                 ret = -LTTNG_ERR_LOAD_IO_FAIL;
3753                 goto end;
3754         }
3755
3756         ret = xmlSchemaValidateDoc(validation_ctx->schema_validation_ctx, doc);
3757         if (ret) {
3758                 ERR("Session configuration file validation failed");
3759                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
3760                 goto end;
3761         }
3762
3763         sessions_node = xmlDocGetRootElement(doc);
3764         if (!sessions_node) {
3765                 ret = -LTTNG_ERR_LOAD_INVALID_CONFIG;
3766                 goto end;
3767         }
3768
3769         for (session_node = xmlFirstElementChild(sessions_node);
3770                 session_node; session_node =
3771                         xmlNextElementSibling(session_node)) {
3772                 ret = process_session_node(session_node,
3773                         session_name, overwrite, overrides);
3774                 if (!session_name && ret) {
3775                         /* Loading error occurred. */
3776                         goto end;
3777                 } else if (session_name) {
3778                         if (ret == 0) {
3779                                 /* Target session found and loaded */
3780                                 session_found = 1;
3781                                 break;
3782                         } else if (ret == -LTTNG_ERR_NO_SESSION) {
3783                                 /*
3784                                  * Ignore this error, we are looking for a
3785                                  * specific session.
3786                                  */
3787                                 ret = 0;
3788                         } else {
3789                                 /* Loading error occurred. */
3790                                 goto end;
3791                         }
3792                 }
3793         }
3794 end:
3795         xmlFreeDoc(doc);
3796         if (!ret) {
3797                 ret = session_found ? 0 : -LTTNG_ERR_LOAD_SESSION_NOENT;
3798         }
3799         return ret;
3800 }
3801
3802 static
3803 int load_session_from_path(const char *path, const char *session_name,
3804         struct session_config_validation_ctx *validation_ctx, int overwrite,
3805         const struct config_load_session_override_attr *overrides)
3806 {
3807         int ret, session_found = !session_name;
3808         DIR *directory = NULL;
3809         struct lttng_dynamic_buffer file_path;
3810         size_t path_len;
3811
3812         assert(path);
3813         assert(validation_ctx);
3814         path_len = strlen(path);
3815         lttng_dynamic_buffer_init(&file_path);
3816         if (path_len >= LTTNG_PATH_MAX) {
3817                 ERR("Session configuration load path \"%s\" length (%zu) exceeds the maximal length allowed (%d)",
3818                                 path, path_len, LTTNG_PATH_MAX);
3819                 ret = -LTTNG_ERR_INVALID;
3820                 goto end;
3821         }
3822
3823         directory = opendir(path);
3824         if (!directory) {
3825                 switch (errno) {
3826                 case ENOTDIR:
3827                         /* Try the file loading. */
3828                         break;
3829                 case ENOENT:
3830                         ret = -LTTNG_ERR_LOAD_SESSION_NOENT;
3831                         goto end;
3832                 default:
3833                         ret = -LTTNG_ERR_LOAD_IO_FAIL;
3834                         goto end;
3835                 }
3836         }
3837         if (directory) {
3838                 size_t file_path_root_len;
3839
3840                 ret = lttng_dynamic_buffer_set_capacity(&file_path,
3841                                 LTTNG_PATH_MAX);
3842                 if (ret) {
3843                         ret = -LTTNG_ERR_NOMEM;
3844                         goto end;
3845                 }
3846
3847                 ret = lttng_dynamic_buffer_append(&file_path, path, path_len);
3848                 if (ret) {
3849                         ret = -LTTNG_ERR_NOMEM;
3850                         goto end;
3851                 }
3852
3853                 if (file_path.data[file_path.size - 1] != '/') {
3854                         ret = lttng_dynamic_buffer_append(&file_path, "/", 1);
3855                         if (ret) {
3856                                 ret = -LTTNG_ERR_NOMEM;
3857                                 goto end;
3858                         }
3859                 }
3860                 file_path_root_len = file_path.size;
3861
3862                 /* Search for *.lttng files */
3863                 for (;;) {
3864                         size_t file_name_len;
3865                         struct dirent *result;
3866
3867                         /*
3868                          * When the end of the directory stream is reached, NULL
3869                          * is returned and errno is kept unchanged. When an
3870                          * error occurs, NULL is returned and errno is set
3871                          * accordingly. To distinguish between the two, set
3872                          * errno to zero before calling readdir().
3873                          *
3874                          * On success, readdir() returns a pointer to a dirent
3875                          * structure. This structure may be statically
3876                          * allocated, do not attempt to free(3) it.
3877                          */
3878                         errno = 0;
3879                         result = readdir(directory);
3880
3881                         /* Reached end of dir stream or error out. */
3882                         if (!result) {
3883                                 if (errno) {
3884                                         PERROR("Failed to enumerate the contents of path \"%s\" while loading session, readdir returned", path);
3885                                         ret = -LTTNG_ERR_LOAD_IO_FAIL;
3886                                         goto end;
3887                                 }
3888                                 break;
3889                         }
3890
3891                         file_name_len = strlen(result->d_name);
3892
3893                         if (file_name_len <=
3894                                 sizeof(DEFAULT_SESSION_CONFIG_FILE_EXTENSION)) {
3895                                 continue;
3896                         }
3897
3898                         if (file_path.size + file_name_len >= LTTNG_PATH_MAX) {
3899                                 WARN("Ignoring file \"%s\" since the path's length (%zu) would exceed the maximal permitted size (%d)",
3900                                                 result->d_name,
3901                                                 /* +1 to account for NULL terminator. */
3902                                                 file_path.size + file_name_len + 1,
3903                                                 LTTNG_PATH_MAX);
3904                                 continue;
3905                         }
3906
3907                         /* Does the file end with .lttng? */
3908                         if (strcmp(DEFAULT_SESSION_CONFIG_FILE_EXTENSION,
3909                                         result->d_name + file_name_len - sizeof(
3910                                         DEFAULT_SESSION_CONFIG_FILE_EXTENSION) + 1)) {
3911                                 continue;
3912                         }
3913
3914                         ret = lttng_dynamic_buffer_append(&file_path, result->d_name,
3915                                         file_name_len + 1);
3916                         if (ret) {
3917                                 ret = -LTTNG_ERR_NOMEM;
3918                                 goto end;
3919                         }
3920
3921                         ret = load_session_from_file(file_path.data, session_name,
3922                                 validation_ctx, overwrite, overrides);
3923                         if (session_name &&
3924                                         (!ret || ret != -LTTNG_ERR_LOAD_SESSION_NOENT)) {
3925                                 session_found = 1;
3926                                 break;
3927                         }
3928                         if (ret && ret != -LTTNG_ERR_LOAD_SESSION_NOENT) {
3929                                 goto end;
3930                         }
3931                         /*
3932                          * Reset the buffer's size to the location of the
3933                          * path's trailing '/'.
3934                          */
3935                         ret = lttng_dynamic_buffer_set_size(&file_path,
3936                                         file_path_root_len);
3937                         if (ret) {
3938                                 ret = -LTTNG_ERR_UNK;
3939                                 goto end;
3940                         }
3941                 }
3942         } else {
3943                 ret = load_session_from_file(path, session_name,
3944                         validation_ctx, overwrite, overrides);
3945                 if (ret) {
3946                         goto end;
3947                 }
3948                 session_found = 1;
3949         }
3950
3951         ret = 0;
3952 end:
3953         if (directory) {
3954                 if (closedir(directory)) {
3955                         PERROR("closedir");
3956                 }
3957         }
3958         if (!ret && !session_found) {
3959                 ret = -LTTNG_ERR_LOAD_SESSION_NOENT;
3960         }
3961         lttng_dynamic_buffer_reset(&file_path);
3962         return ret;
3963 }
3964
3965 /*
3966  * Validate that the given path's credentials and the current process have the
3967  * same UID. If so, return 1 else return 0 if it does NOT match.
3968  */
3969 static int validate_path_creds(const char *path)
3970 {
3971         int ret, uid = getuid();
3972         struct stat buf;
3973
3974         assert(path);
3975
3976         if (uid == 0) {
3977                 goto valid;
3978         }
3979
3980         ret = stat(path, &buf);
3981         if (ret < 0) {
3982                 if (errno != ENOENT) {
3983                         PERROR("stat");
3984                 }
3985                 goto valid;
3986         }
3987
3988         if (buf.st_uid != uid) {
3989                 goto invalid;
3990         }
3991
3992 valid:
3993         return 1;
3994 invalid:
3995         return 0;
3996 }
3997
3998 LTTNG_HIDDEN
3999 int config_load_session(const char *path, const char *session_name,
4000                 int overwrite, unsigned int autoload,
4001                 const struct config_load_session_override_attr *overrides)
4002 {
4003         int ret;
4004         bool session_loaded = false;
4005         const char *path_ptr = NULL;
4006         struct session_config_validation_ctx validation_ctx = { 0 };
4007
4008         ret = init_session_config_validation_ctx(&validation_ctx);
4009         if (ret) {
4010                 goto end;
4011         }
4012
4013         if (!path) {
4014                 const char *home_path;
4015                 const char *sys_path;
4016
4017                 /* Try home path */
4018                 home_path = utils_get_home_dir();
4019                 if (home_path) {
4020                         char path_buf[PATH_MAX];
4021
4022                         /*
4023                          * Try user session configuration path. Ignore error here so we can
4024                          * continue loading the system wide sessions.
4025                          */
4026                         if (autoload) {
4027                                 ret = snprintf(path_buf, sizeof(path_buf),
4028                                                 DEFAULT_SESSION_HOME_CONFIGPATH
4029                                                 "/" DEFAULT_SESSION_CONFIG_AUTOLOAD,
4030                                                 home_path);
4031                                 if (ret < 0) {
4032                                         PERROR("snprintf session autoload home config path");
4033                                         ret = -LTTNG_ERR_INVALID;
4034                                         goto end;
4035                                 }
4036
4037                                 /*
4038                                  * Credentials are only validated for the autoload in order to
4039                                  * avoid any user session daemon to try to load kernel sessions
4040                                  * automatically and failing all the times.
4041                                  */
4042                                 ret = validate_path_creds(path_buf);
4043                                 if (ret) {
4044                                         path_ptr = path_buf;
4045                                 }
4046                         } else {
4047                                 ret = snprintf(path_buf, sizeof(path_buf),
4048                                                 DEFAULT_SESSION_HOME_CONFIGPATH,
4049                                                 home_path);
4050                                 if (ret < 0) {
4051                                         PERROR("snprintf session home config path");
4052                                         ret = -LTTNG_ERR_INVALID;
4053                                         goto end;
4054                                 }
4055                                 path_ptr = path_buf;
4056                         }
4057                         if (path_ptr) {
4058                                 ret = load_session_from_path(path_ptr, session_name,
4059                                                 &validation_ctx, overwrite, overrides);
4060                                 if (ret && ret != -LTTNG_ERR_LOAD_SESSION_NOENT) {
4061                                         goto end;
4062                                 }
4063                                 /*
4064                                  * Continue even if the session was found since we have to try
4065                                  * the system wide sessions.
4066                                  */
4067                                 session_loaded = true;
4068                         }
4069                 }
4070
4071                 /* Reset path pointer for the system wide dir. */
4072                 path_ptr = NULL;
4073
4074                 /* Try system wide configuration directory. */
4075                 if (autoload) {
4076                         sys_path = DEFAULT_SESSION_SYSTEM_CONFIGPATH "/"
4077                                 DEFAULT_SESSION_CONFIG_AUTOLOAD;
4078                         ret = validate_path_creds(sys_path);
4079                         if (ret) {
4080                                 path_ptr = sys_path;
4081                         }
4082                 } else {
4083                         sys_path = DEFAULT_SESSION_SYSTEM_CONFIGPATH;
4084                         path_ptr = sys_path;
4085                 }
4086
4087                 if (path_ptr) {
4088                         ret = load_session_from_path(path_ptr, session_name,
4089                                         &validation_ctx, overwrite, overrides);
4090                         if (!ret) {
4091                                 session_loaded = true;
4092                         }
4093                 } else {
4094                         ret = 0;
4095                 }
4096         } else {
4097                 ret = access(path, F_OK);
4098                 if (ret < 0) {
4099                         PERROR("access");
4100                         switch (errno) {
4101                         case ENOENT:
4102                                 ret = -LTTNG_ERR_INVALID;
4103                                 WARN("Session configuration path does not exist.");
4104                                 break;
4105                         case EACCES:
4106                                 ret = -LTTNG_ERR_EPERM;
4107                                 break;
4108                         default:
4109                                 ret = -LTTNG_ERR_UNK;
4110                                 break;
4111                         }
4112                         goto end;
4113                 }
4114
4115                 ret = load_session_from_path(path, session_name,
4116                         &validation_ctx, overwrite, overrides);
4117         }
4118 end:
4119         fini_session_config_validation_ctx(&validation_ctx);
4120         if (ret == -LTTNG_ERR_LOAD_SESSION_NOENT && !session_name && !path) {
4121                 /*
4122                  * Don't report an error if no sessions are found when called
4123                  * without a session_name or a search path.
4124                  */
4125                 ret = 0;
4126         }
4127
4128         if (session_loaded && ret == -LTTNG_ERR_LOAD_SESSION_NOENT) {
4129                 /* A matching session was found in one of the search paths. */
4130                 ret = 0;
4131         }
4132         return ret;
4133 }
4134
4135 static
4136 void __attribute__((destructor)) session_config_exit(void)
4137 {
4138         xmlCleanupParser();
4139 }