libustcmd/ustcmd.c

   1 /* Copyright (C) 2009  Pierre-Marc Fournier, Philippe Proulx-Barrette
   2  *
   3  * This library is free software; you can redistribute it and/or
   4  * modify it under the terms of the GNU Lesser General Public
   5  * License as published by the Free Software Foundation; either
   6  * version 2.1 of the License, or (at your option) any later version.
   7  *
   8  * This library is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * Lesser General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public
  14  * License along with this library; if not, write to the Free Software
  15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
  16  */
  17
  18 #define _GNU_SOURCE
  19 #include <stdio.h>
  20 #include <unistd.h>
  21 #include <getopt.h>
  22 #include <stdlib.h>
  23 #include <fcntl.h>
  24 #include <string.h>
  25 #include <dirent.h>
  26
  27 #include "ustcomm.h"
  28 #include "ust/ustcmd.h"
  29 #include "usterr.h"
  30
  31 pid_t *ustcmd_get_online_pids(void)
  32 {
  33         struct dirent *dirent;
  34         DIR *dir;
  35         unsigned int ret_size = 1 * sizeof(pid_t), i = 0;
  36
  37         dir = opendir(SOCK_DIR);
  38         if (!dir) {
  39                 return NULL;
  40         }
  41
  42         pid_t *ret = (pid_t *) malloc(ret_size);
  43
  44         while ((dirent = readdir(dir))) {
  45                 if (!strcmp(dirent->d_name, ".") ||
  46                         !strcmp(dirent->d_name, "..")) {
  47
  48                         continue;
  49                 }
  50
  51                 if (dirent->d_type != DT_DIR &&
  52                         !!strcmp(dirent->d_name, "ustd")) {
  53
  54                         sscanf(dirent->d_name, "%u", (unsigned int *) &ret[i]);
  55                         if (pid_is_online(ret[i])) {
  56                                 ret_size += sizeof(pid_t);
  57                                 ret = (pid_t *) realloc(ret, ret_size);
  58                                 ++i;
  59                         }
  60                 }
  61         }
  62
  63         ret[i] = 0; /* Array end */
  64
  65         if (ret[0] == 0) {
  66                  /* No PID at all */
  67                 free(ret);
  68                 return NULL;
  69         }
  70
  71         closedir(dir);
  72         return ret;
  73 }
  74
  75 /**
  76  * Sets marker state (USTCMD_MS_ON or USTCMD_MS_OFF).
  77  *
  78  * @param mn    Marker name
  79  * @param state Marker's new state
  80  * @param pid   Traced process ID
  81  * @return      0 if successful, or errors {USTCMD_ERR_GEN, USTCMD_ERR_ARG}
  82  */
  83 int ustcmd_set_marker_state(const char *mn, int state, pid_t pid)
  84 {
  85         char *cmd_str [] = {"disable_marker", "enable_marker"};
  86         char *cmd;
  87         int result;
  88
  89         if (mn == NULL) {
  90                 return USTCMD_ERR_ARG;
  91         }
  92
  93         if (asprintf(&cmd, "%s %s", cmd_str[state], mn) < 0) {
  94                 ERR("ustcmd_set_marker_state : asprintf failed (%s %s)",
  95                     cmd_str[state], mn);
  96                 return USTCMD_ERR_GEN;
  97         }
  98
  99         result = ustcmd_send_cmd(cmd, pid, NULL);
 100         if (result != 1) {
 101                 free(cmd);
 102                 return USTCMD_ERR_GEN;
 103         }
 104
 105         free(cmd);
 106         return 0;
 107 }
 108
 109 /**
 110  * Set subbuffer size.
 111  *
 112  * @param channel_size  Channel name and size
 113  * @param pid           Traced process ID
 114  * @return              0 if successful, or error
 115  */
 116 int ustcmd_set_subbuf_size(const char *channel_size, pid_t pid)
 117 {
 118         char *cmd;
 119         int result;
 120
 121         if (asprintf(&cmd, "%s %s", "set_subbuf_size", channel_size) < 0) {
 122                 ERR("ustcmd_set_subbuf_size : asprintf failed (set_subbuf_size %s)",
 123                     channel_size);
 124                 return -1;
 125         }
 126
 127         result = ustcmd_send_cmd(cmd, pid, NULL);
 128         if (result != 1) {
 129                 free(cmd);
 130                 return 1;
 131         }
 132
 133         free(cmd);
 134         return 0;
 135 }
 136
 137 /**
 138  * Set subbuffer num.
 139  *
 140  * @param channel_num   Channel name and num
 141  * @param pid           Traced process ID
 142  * @return              0 if successful, or error
 143  */
 144 int ustcmd_set_subbuf_num(const char *channel_size, pid_t pid)
 145 {
 146         char *cmd;
 147         int result;
 148
 149         if (asprintf(&cmd, "%s %s", "set_subbuf_num", channel_size) < 0) {
 150                 ERR("ustcmd_set_subbuf_num : asprintf failed (set_subbuf_num %s",
 151                     channel_size);
 152                 return -1;
 153         }
 154
 155         result = ustcmd_send_cmd(cmd, pid, NULL);
 156         if (result != 1) {
 157                 free(cmd);
 158                 return 1;
 159         }
 160
 161         free(cmd);
 162         return 0;
 163 }
 164
 165 /**
 166  * Get subbuffer size.
 167  *
 168  * @param channel       Channel name
 169  * @param pid           Traced process ID
 170  * @return              subbuf size if successful, or error
 171  */
 172 int ustcmd_get_subbuf_size(const char *channel, pid_t pid)
 173 {
 174         char *cmd, *reply;
 175         int result;
 176
 177         /* format: channel_cpu */
 178         if (asprintf(&cmd, "%s %s_0", "get_subbuf_size", channel) < 0) {
 179                 ERR("ustcmd_get_subbuf_size : asprintf failed (get_subbuf_size, %s_0",
 180                     channel);
 181                 return -1;
 182         }
 183
 184         result = ustcmd_send_cmd(cmd, pid, &reply);
 185         if (result != 1) {
 186                 free(cmd);
 187                 return -1;
 188         }
 189
 190         result = atoi(reply);
 191         free(cmd);
 192         free(reply);
 193         return result;
 194 }
 195
 196 /**
 197  * Get subbuffer num.
 198  *
 199  * @param channel       Channel name
 200  * @param pid           Traced process ID
 201  * @return              subbuf cnf if successful, or error
 202  */
 203 int ustcmd_get_subbuf_num(const char *channel, pid_t pid)
 204 {
 205         char *cmd, *reply;
 206         int result;
 207
 208         /* format: channel_cpu */
 209         if (asprintf(&cmd, "%s %s_0", "get_n_subbufs", channel) < 0) {
 210                 ERR("ustcmd_get_subbuf_num : asprintf failed (get_n_subbufs, %s_0",
 211                     channel);
 212                 return -1;
 213         }
 214
 215         result = ustcmd_send_cmd(cmd, pid, &reply);
 216         if (result != 1) {
 217                 free(cmd);
 218                 return -1;
 219         }
 220
 221         result = atoi(reply);
 222         free(cmd);
 223         free(reply);
 224         return result;
 225 }
 226
 227 /**
 228  * Destroys an UST trace according to a PID.
 229  *
 230  * @param pid   Traced process ID
 231  * @return      0 if successful, or error USTCMD_ERR_GEN
 232  */
 233 int ustcmd_destroy_trace(pid_t pid)
 234 {
 235         int result;
 236
 237         result = ustcmd_send_cmd("trace_destroy", pid, NULL);
 238         if (result != 1) {
 239                 return USTCMD_ERR_GEN;
 240         }
 241
 242         return 0;
 243 }
 244
 245 /**
 246  * Starts an UST trace (and setups it) according to a PID.
 247  *
 248  * @param pid   Traced process ID
 249  * @return      0 if successful, or error USTCMD_ERR_GEN
 250  */
 251 int ustcmd_setup_and_start(pid_t pid)
 252 {
 253         int result;
 254
 255         result = ustcmd_send_cmd("start", pid, NULL);
 256         if (result != 1) {
 257                 return USTCMD_ERR_GEN;
 258         }
 259
 260         return 0;
 261 }
 262
 263 /**
 264  * Creates an UST trace according to a PID.
 265  *
 266  * @param pid   Traced process ID
 267  * @return      0 if successful, or error USTCMD_ERR_GEN
 268  */
 269 int ustcmd_create_trace(pid_t pid)
 270 {
 271         int result;
 272
 273         result = ustcmd_send_cmd("trace_create", pid, NULL);
 274         if (result != 1) {
 275                 return USTCMD_ERR_GEN;
 276         }
 277
 278         return 0;
 279 }
 280
 281 /**
 282  * Starts an UST trace according to a PID.
 283  *
 284  * @param pid   Traced process ID
 285  * @return      0 if successful, or error USTCMD_ERR_GEN
 286  */
 287 int ustcmd_start_trace(pid_t pid)
 288 {
 289         int result;
 290
 291         result = ustcmd_send_cmd("trace_start", pid, NULL);
 292         if (result != 1) {
 293                 return USTCMD_ERR_GEN;
 294         }
 295
 296         return 0;
 297 }
 298
 299 /**
 300  * Alloc an UST trace according to a PID.
 301  *
 302  * @param pid   Traced process ID
 303  * @return      0 if successful, or error USTCMD_ERR_GEN
 304  */
 305 int ustcmd_alloc_trace(pid_t pid)
 306 {
 307         int result;
 308
 309         result = ustcmd_send_cmd("trace_alloc", pid, NULL);
 310         if (result != 1) {
 311                 return USTCMD_ERR_GEN;
 312         }
 313
 314         return 0;
 315 }
 316
 317 /**
 318  * Stops an UST trace according to a PID.
 319  *
 320  * @param pid   Traced process ID
 321  * @return      0 if successful, or error USTCMD_ERR_GEN
 322  */
 323 int ustcmd_stop_trace(pid_t pid)
 324 {
 325         int result;
 326
 327         result = ustcmd_send_cmd("trace_stop", pid, NULL);
 328         if (result != 1) {
 329                 return USTCMD_ERR_GEN;
 330         }
 331
 332         return 0;
 333 }
 334
 335 /**
 336  * Counts newlines ('\n') in a string.
 337  *
 338  * @param str   String to search in
 339  * @return      Total newlines count
 340  */
 341 unsigned int ustcmd_count_nl(const char *str)
 342 {
 343         unsigned int i = 0, tot = 0;
 344
 345         while (str[i] != '\0') {
 346                 if (str[i] == '\n') {
 347                         ++tot;
 348                 }
 349                 ++i;
 350         }
 351
 352         return tot;
 353 }
 354
 355 /**
 356  * Frees a CMSF array.
 357  *
 358  * @param cmsf  CMSF array to free
 359  * @return      0 if successful, or error USTCMD_ERR_ARG
 360  */
 361 int ustcmd_free_cmsf(struct marker_status *cmsf)
 362 {
 363         if (cmsf == NULL) {
 364                 return USTCMD_ERR_ARG;
 365         }
 366
 367         unsigned int i = 0;
 368         while (cmsf[i].channel != NULL) {
 369                 free(cmsf[i].channel);
 370                 free(cmsf[i].marker);
 371                 free(cmsf[i].fs);
 372                 ++i;
 373         }
 374         free(cmsf);
 375
 376         return 0;
 377 }
 378
 379 /**
 380  * Gets channel/marker/state/format string for a given PID.
 381  *
 382  * @param cmsf  Pointer to CMSF array to be filled (callee allocates, caller
 383  *              frees with `ustcmd_free_cmsf')
 384  * @param pid   Targeted PID
 385  * @return      0 if successful, or -1 on error
 386  */
 387 int ustcmd_get_cmsf(struct marker_status **cmsf, const pid_t pid)
 388 {
 389         char *big_str = NULL;
 390         int result;
 391         struct marker_status *tmp_cmsf = NULL;
 392         unsigned int i = 0, cmsf_ind = 0;
 393
 394         if (cmsf == NULL) {
 395                 return -1;
 396         }
 397         result = ustcmd_send_cmd("list_markers", pid, &big_str);
 398         if (result != 1) {
 399                 ERR("error while getting markers list");
 400                 return -1;
 401         }
 402
 403         tmp_cmsf = (struct marker_status *) malloc(sizeof(struct marker_status) *
 404                 (ustcmd_count_nl(big_str) + 1));
 405         if (tmp_cmsf == NULL) {
 406                 ERR("Failed to allocate CMSF array");
 407                 return -1;
 408         }
 409
 410         /* Parse received reply string (format: "[chan]/[mark] [st] [fs]"): */
 411         while (big_str[i] != '\0') {
 412                 char state;
 413
 414                 sscanf(big_str + i, "marker: %a[^/]/%a[^ ] %c %a[^\n]",
 415                         &tmp_cmsf[cmsf_ind].channel,
 416                         &tmp_cmsf[cmsf_ind].marker,
 417                         &state,
 418                         &tmp_cmsf[cmsf_ind].fs);
 419                 tmp_cmsf[cmsf_ind].state = (state == USTCMD_MS_CHR_ON ?
 420                         USTCMD_MS_ON : USTCMD_MS_OFF); /* Marker state */
 421
 422                 while (big_str[i] != '\n') {
 423                         ++i; /* Go to next '\n' */
 424                 }
 425                 ++i; /* Skip current pointed '\n' */
 426                 ++cmsf_ind;
 427         }
 428         tmp_cmsf[cmsf_ind].channel = NULL;
 429         tmp_cmsf[cmsf_ind].marker = NULL;
 430         tmp_cmsf[cmsf_ind].fs = NULL;
 431
 432         *cmsf = tmp_cmsf;
 433
 434         free(big_str);
 435         return 0;
 436 }
 437
 438
 439 /**
 440  * Frees a TES array.
 441  *
 442  * @param tes   TES array to free
 443  * @return      0 if successful, or error USTCMD_ERR_ARG
 444  */
 445 int ustcmd_free_tes(struct trace_event_status *tes)
 446 {
 447         if (tes == NULL) {
 448                 return USTCMD_ERR_ARG;
 449         }
 450
 451         unsigned int i = 0;
 452         while (tes[i].name != NULL) {
 453                 free(tes[i].name);
 454                 ++i;
 455         }
 456         free(tes);
 457
 458         return 0;
 459 }
 460
 461 /**
 462  * Gets trace_events string for a given PID.
 463  *
 464  * @param tes   Pointer to TES array to be filled (callee allocates, caller
 465  *              frees with `ustcmd_free_tes')
 466  * @param pid   Targeted PID
 467  * @return      0 if successful, or -1 on error
 468  */
 469 int ustcmd_get_tes(struct trace_event_status **tes,
 470                             const pid_t pid)
 471 {
 472         char *big_str = NULL;
 473         int result;
 474         struct trace_event_status *tmp_tes = NULL;
 475         unsigned int i = 0, tes_ind = 0;
 476
 477         if (tes == NULL) {
 478                 return -1;
 479         }
 480
 481         result = ustcmd_send_cmd("list_trace_events", pid, &big_str);
 482         if (result != 1) {
 483                 ERR("error while getting trace_event list");
 484                 return -1;
 485         }
 486
 487         tmp_tes = (struct trace_event_status *)
 488                 zmalloc(sizeof(struct trace_event_status) *
 489                         (ustcmd_count_nl(big_str) + 1));
 490         if (tmp_tes == NULL) {
 491                 ERR("Failed to allocate TES array");
 492                 return -1;
 493         }
 494
 495         /* Parse received reply string (format: "[name]"): */
 496         while (big_str[i] != '\0') {
 497                 char state;
 498
 499                 sscanf(big_str + i, "trace_event: %a[^\n]",
 500                         &tmp_tes[tes_ind].name);
 501                 while (big_str[i] != '\n') {
 502                         ++i; /* Go to next '\n' */
 503                 }
 504                 ++i; /* Skip current pointed '\n' */
 505                 ++tes_ind;
 506         }
 507         tmp_tes[tes_ind].name = NULL;
 508
 509         *tes = tmp_tes;
 510
 511         free(big_str);
 512         return 0;
 513 }
 514
 515 /**
 516  * Set socket path
 517  *
 518  * @param sock_path     Socket path
 519  * @param pid           Traced process ID
 520  * @return              0 if successful, or error
 521  */
 522 int ustcmd_set_sock_path(const char *sock_path, pid_t pid)
 523 {
 524         char *cmd;
 525         int result;
 526
 527         if (asprintf(&cmd, "%s %s", "set_sock_path", sock_path) < 0) {
 528                 ERR("ustcmd_set_sock_path : asprintf failed (set_sock_path, %s",
 529                     sock_path);
 530                 return -1;
 531         }
 532
 533         result = ustcmd_send_cmd(cmd, pid, NULL);
 534         if (result != 1) {
 535                 free(cmd);
 536                 return USTCMD_ERR_GEN;
 537         }
 538
 539         free(cmd);
 540         return 0;
 541 }
 542
 543 /**
 544  * Get socket path
 545  *
 546  * @param sock_path     Pointer to where the socket path will be returned
 547  * @param pid           Traced process ID
 548  * @return              0 if successful, or error
 549  */
 550 int ustcmd_get_sock_path(char **sock_path, pid_t pid)
 551 {
 552         char *cmd, *reply;
 553         int result;
 554
 555         if (asprintf(&cmd, "%s", "get_sock_path") < 0) {
 556                 ERR("ustcmd_get_sock_path : asprintf failed");
 557                 return USTCMD_ERR_GEN;
 558         }
 559
 560         result = ustcmd_send_cmd(cmd, pid, &reply);
 561         if (result != 1) {
 562                 free(cmd);
 563                 return USTCMD_ERR_GEN;
 564         }
 565
 566         free(cmd);
 567         *sock_path = reply;
 568         return 0;
 569 }
 570
 571 int ustcmd_force_switch(pid_t pid)
 572 {
 573         int result;
 574
 575         result = ustcmd_send_cmd("force_switch", pid, NULL);
 576         if (result != 1) {
 577                 return USTCMD_ERR_GEN;
 578         }
 579
 580         return 0;
 581 }
 582
 583 /**
 584  * Sends a given command to a traceable process
 585  *
 586  * @param cmd   Null-terminated command to send
 587  * @param pid   Targeted PID
 588  * @param reply Pointer to string to be filled with a reply string (must
 589  *              be NULL if no reply is needed for the given command).
 590  * @return      -1 if not successful, 0 on EOT, 1 on success
 591  */
 592
 593 int ustcmd_send_cmd(const char *cmd, const pid_t pid, char **reply)
 594 {
 595         struct ustcomm_connection conn;
 596         int retval;
 597
 598         if (ustcomm_connect_app(pid, &conn)) {
 599                 ERR("could not connect to PID %u", (unsigned int) pid);
 600                 return -1;
 601         }
 602
 603         retval = ustcomm_send_request(&conn, cmd, reply);
 604
 605         ustcomm_close_app(&conn);
 606
 607         return retval;
 608 }