include/ust-comm.h

   1 /*
   2  * SPDX-License-Identifier: LGPL-2.1-only
   3  *
   4  * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
   5  * Copyright (C) 2011 Julien Desfossez <julien.desfossez@polymtl.ca>
   6  * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   7  */
   8
   9 /*
  10  * This header is meant for liblttng and libust internal use ONLY.
  11  * These declarations should NOT be considered stable API.
  12  */
  13
  14 #ifndef _LTTNG_UST_COMM_H
  15 #define _LTTNG_UST_COMM_H
  16
  17 #include <stdint.h>
  18 #include <limits.h>
  19 #include <unistd.h>
  20 #include <lttng/ust-abi.h>
  21 #include <lttng/ust-error.h>
  22 #include <lttng/ust-compiler.h>
  23 #include <lttng/ust-ctl.h>
  24 #include "helper.h"
  25
  26 #ifndef LTTNG_PACKED
  27 #error "LTTNG_PACKED should be defined"
  28 #endif
  29
  30 /*
  31  * Default timeout the application waits for the sessiond to send its
  32  * "register done" command. Can be overridden with the environment
  33  * variable "LTTNG_UST_REGISTER_TIMEOUT". Note that if the sessiond is not
  34  * found, the application proceeds directly without any delay.
  35  */
  36 #define LTTNG_UST_DEFAULT_CONSTRUCTOR_TIMEOUT_MS        CONFIG_LTTNG_UST_DEFAULT_CONSTRUCTOR_TIMEOUT_MS
  37
  38 #define LTTNG_DEFAULT_RUNDIR                            LTTNG_SYSTEM_RUNDIR
  39 #define LTTNG_DEFAULT_HOME_RUNDIR                       ".lttng"
  40
  41 /* Queue size of listen(2) */
  42 #define LTTNG_UST_COMM_MAX_LISTEN                       10
  43 #define LTTNG_UST_COMM_REG_MSG_PADDING                  64
  44
  45 struct lttng_event_field;
  46 struct lttng_ctx_field;
  47 struct lttng_enum_entry;
  48 struct lttng_integer_type;
  49 struct lttng_session;
  50
  51 struct ustctl_reg_msg {
  52         uint32_t magic;
  53         uint32_t major;
  54         uint32_t minor;
  55         uint32_t pid;
  56         uint32_t ppid;
  57         uint32_t uid;
  58         uint32_t gid;
  59         uint32_t bits_per_long;
  60         uint32_t uint8_t_alignment;
  61         uint32_t uint16_t_alignment;
  62         uint32_t uint32_t_alignment;
  63         uint32_t uint64_t_alignment;
  64         uint32_t long_alignment;
  65         uint32_t socket_type;                   /* enum ustctl_socket_type */
  66         char name[LTTNG_UST_ABI_PROCNAME_LEN];  /* process name */
  67         char padding[LTTNG_UST_COMM_REG_MSG_PADDING];
  68 } LTTNG_PACKED;
  69
  70 /*
  71  * Data structure for the commands sent from sessiond to UST.
  72  */
  73 #define USTCOMM_MSG_PADDING1            32
  74 #define USTCOMM_MSG_PADDING2            32
  75 struct ustcomm_ust_msg {
  76         uint32_t handle;
  77         uint32_t cmd;
  78         char padding[USTCOMM_MSG_PADDING1];
  79         union {
  80                 struct lttng_ust_channel channel;
  81                 struct lttng_ust_stream stream;
  82                 struct lttng_ust_event event;
  83                 struct lttng_ust_context context;
  84                 struct lttng_ust_tracer_version version;
  85                 struct lttng_ust_tracepoint_iter tracepoint;
  86                 struct {
  87                         uint32_t data_size;     /* following filter data */
  88                         uint32_t reloc_offset;
  89                         uint64_t seqnum;
  90                 } LTTNG_PACKED filter;
  91                 struct {
  92                         uint32_t count; /* how many names follow */
  93                 } LTTNG_PACKED exclusion;
  94                 struct {
  95                         uint32_t data_size;     /* following capture data */
  96                         uint32_t reloc_offset;
  97                         uint64_t seqnum;
  98                 } LTTNG_PACKED capture;
  99                 struct lttng_ust_counter counter;
 100                 struct lttng_ust_counter_global counter_global;
 101                 struct lttng_ust_counter_cpu counter_cpu;
 102                 /*
 103                  * For LTTNG_UST_EVENT_NOTIFIER_CREATE, a struct
 104                  * lttng_ust_event_notifier implicitly follows struct
 105                  * ustcomm_ust_msg.
 106                  */
 107                 struct {
 108                         /* Length of struct lttng_ust_event_notifier */
 109                         uint32_t len;
 110                 } event_notifier;
 111                 char padding[USTCOMM_MSG_PADDING2];
 112         } u;
 113 } LTTNG_PACKED;
 114
 115 /*
 116  * Data structure for the response from UST to the session daemon.
 117  * cmd_type is sent back in the reply for validation.
 118  */
 119 #define USTCOMM_REPLY_PADDING1          32
 120 #define USTCOMM_REPLY_PADDING2          32
 121 struct ustcomm_ust_reply {
 122         uint32_t handle;
 123         uint32_t cmd;
 124         int32_t ret_code;       /* enum ustcomm_return_code */
 125         uint32_t ret_val;       /* return value */
 126         char padding[USTCOMM_REPLY_PADDING1];
 127         union {
 128                 struct {
 129                         uint64_t memory_map_size;
 130                 } LTTNG_PACKED channel;
 131                 struct {
 132                         uint64_t memory_map_size;
 133                 } LTTNG_PACKED stream;
 134                 struct lttng_ust_tracer_version version;
 135                 struct lttng_ust_tracepoint_iter tracepoint;
 136                 char padding[USTCOMM_REPLY_PADDING2];
 137         } u;
 138 } LTTNG_PACKED;
 139
 140 struct ustcomm_notify_hdr {
 141         uint32_t notify_cmd;
 142 } LTTNG_PACKED;
 143
 144 #define USTCOMM_NOTIFY_EVENT_MSG_PADDING        32
 145 struct ustcomm_notify_event_msg {
 146         uint32_t session_objd;
 147         uint32_t channel_objd;
 148         char event_name[LTTNG_UST_SYM_NAME_LEN];
 149         int32_t loglevel;
 150         uint32_t signature_len;
 151         uint32_t fields_len;
 152         uint32_t model_emf_uri_len;
 153         char padding[USTCOMM_NOTIFY_EVENT_MSG_PADDING];
 154         /* followed by signature, fields, and model_emf_uri */
 155 } LTTNG_PACKED;
 156
 157 #define USTCOMM_NOTIFY_EVENT_REPLY_PADDING      32
 158 struct ustcomm_notify_event_reply {
 159         int32_t ret_code;       /* 0: ok, negative: error code */
 160         uint32_t event_id;
 161         char padding[USTCOMM_NOTIFY_EVENT_REPLY_PADDING];
 162 } LTTNG_PACKED;
 163
 164 #define USTCOMM_NOTIFY_ENUM_MSG_PADDING         32
 165 struct ustcomm_notify_enum_msg {
 166         uint32_t session_objd;
 167         char enum_name[LTTNG_UST_SYM_NAME_LEN];
 168         uint32_t entries_len;
 169         char padding[USTCOMM_NOTIFY_ENUM_MSG_PADDING];
 170         /* followed by enum entries */
 171 } LTTNG_PACKED;
 172
 173 #define USTCOMM_NOTIFY_EVENT_REPLY_PADDING      32
 174 struct ustcomm_notify_enum_reply {
 175         int32_t ret_code;       /* 0: ok, negative: error code */
 176         uint64_t enum_id;
 177         char padding[USTCOMM_NOTIFY_EVENT_REPLY_PADDING];
 178 } LTTNG_PACKED;
 179
 180 #define USTCOMM_NOTIFY_CHANNEL_MSG_PADDING      32
 181 struct ustcomm_notify_channel_msg {
 182         uint32_t session_objd;
 183         uint32_t channel_objd;
 184         uint32_t ctx_fields_len;
 185         char padding[USTCOMM_NOTIFY_CHANNEL_MSG_PADDING];
 186         /* followed by context fields */
 187 } LTTNG_PACKED;
 188
 189 #define USTCOMM_NOTIFY_CHANNEL_REPLY_PADDING    32
 190 struct ustcomm_notify_channel_reply {
 191         int32_t ret_code;       /* 0: ok, negative: error code */
 192         uint32_t chan_id;
 193         uint32_t header_type;   /* enum ustctl_channel_header */
 194         char padding[USTCOMM_NOTIFY_CHANNEL_REPLY_PADDING];
 195 } LTTNG_PACKED;
 196
 197 /*
 198  * LTTNG_UST_TRACEPOINT_FIELD_LIST reply is followed by a
 199  * struct lttng_ust_field_iter field.
 200  */
 201
 202 extern int ustcomm_create_unix_sock(const char *pathname);
 203 extern int ustcomm_connect_unix_sock(const char *pathname,
 204                 long timeout);
 205 extern int ustcomm_accept_unix_sock(int sock);
 206 extern int ustcomm_listen_unix_sock(int sock);
 207 extern int ustcomm_close_unix_sock(int sock);
 208
 209 extern ssize_t ustcomm_recv_unix_sock(int sock, void *buf, size_t len);
 210 extern ssize_t ustcomm_send_unix_sock(int sock, const void *buf, size_t len);
 211 extern ssize_t ustcomm_send_fds_unix_sock(int sock, int *fds, size_t nb_fd);
 212 extern ssize_t ustcomm_recv_fds_unix_sock(int sock, int *fds, size_t nb_fd);
 213
 214 extern const char *ustcomm_get_readable_code(int code);
 215 extern int ustcomm_send_app_msg(int sock, struct ustcomm_ust_msg *lum);
 216 extern int ustcomm_recv_app_reply(int sock, struct ustcomm_ust_reply *lur,
 217                 uint32_t expected_handle, uint32_t expected_cmd);
 218 extern int ustcomm_send_app_cmd(int sock,
 219                 struct ustcomm_ust_msg *lum,
 220                 struct ustcomm_ust_reply *lur);
 221 int ustcomm_recv_fd(int sock);
 222
 223 ssize_t ustcomm_recv_channel_from_sessiond(int sock,
 224                 void **chan_data, uint64_t len, int *wakeup_fd);
 225 int ustcomm_recv_stream_from_sessiond(int sock,
 226                 uint64_t *memory_map_size,
 227                 int *shm_fd, int *wakeup_fd);
 228 LTTNG_HIDDEN
 229 ssize_t ustcomm_recv_event_notifier_notif_fd_from_sessiond(int sock,
 230                 int *event_notifier_notif_fd);
 231
 232 LTTNG_HIDDEN
 233 ssize_t ustcomm_recv_counter_from_sessiond(int sock,
 234                 void **counter_data, uint64_t len);
 235 LTTNG_HIDDEN
 236 int ustcomm_recv_counter_shm_from_sessiond(int sock,
 237                 int *shm_fd);
 238
 239 /*
 240  * Returns 0 on success, negative error value on error.
 241  * Returns -EPIPE or -ECONNRESET if other end has hung up.
 242  */
 243 int ustcomm_send_reg_msg(int sock,
 244                 enum ustctl_socket_type type,
 245                 uint32_t bits_per_long,
 246                 uint32_t uint8_t_alignment,
 247                 uint32_t uint16_t_alignment,
 248                 uint32_t uint32_t_alignment,
 249                 uint32_t uint64_t_alignment,
 250                 uint32_t long_alignment);
 251
 252 /*
 253  * Returns 0 on success, negative error value on error.
 254  * Returns -EPIPE or -ECONNRESET if other end has hung up.
 255  */
 256 int ustcomm_register_event(int sock,
 257         struct lttng_session *session,
 258         int session_objd,               /* session descriptor */
 259         int channel_objd,               /* channel descriptor */
 260         const char *event_name,         /* event name (input) */
 261         int loglevel,
 262         const char *signature,          /* event signature (input) */
 263         size_t nr_fields,               /* fields */
 264         const struct lttng_event_field *fields,
 265         const char *model_emf_uri,
 266         uint32_t *id);                  /* event id (output) */
 267
 268 /*
 269  * Returns 0 on success, negative error value on error.
 270  * Returns -EPIPE or -ECONNRESET if other end has hung up.
 271  */
 272 int ustcomm_register_enum(int sock,
 273         int session_objd,               /* session descriptor */
 274         const char *enum_name,          /* enum name (input) */
 275         size_t nr_entries,              /* entries */
 276         const struct lttng_enum_entry *entries,
 277         uint64_t *id);                  /* enum id (output) */
 278
 279 /*
 280  * Returns 0 on success, negative error value on error.
 281  * Returns -EPIPE or -ECONNRESET if other end has hung up.
 282  */
 283 int ustcomm_register_channel(int sock,
 284         struct lttng_session *session,
 285         int session_objd,               /* session descriptor */
 286         int channel_objd,               /* channel descriptor */
 287         size_t nr_ctx_fields,
 288         const struct lttng_ctx_field *ctx_fields,
 289         uint32_t *chan_id,              /* channel id (output) */
 290         int *header_type);              /* header type (output) */
 291
 292 int ustcomm_setsockopt_rcv_timeout(int sock, unsigned int msec);
 293 int ustcomm_setsockopt_snd_timeout(int sock, unsigned int msec);
 294
 295 #endif  /* _LTTNG_UST_COMM_H */