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                 /*
 112                  * For LTTNG_UST_COUNTER_EVENT, a struct
 113                  * lttng_ust_counter_event implicitly follows struct
 114                  * ustcomm_ust_msg.
 115                  */
 116                 struct {
 117                         /* Length of struct lttng_ust_counter_event */
 118                         uint32_t len;
 119                 } counter_event;
 120                 char padding[USTCOMM_MSG_PADDING2];
 121         } u;
 122 } LTTNG_PACKED;
 123
 124 /*
 125  * Data structure for the response from UST to the session daemon.
 126  * cmd_type is sent back in the reply for validation.
 127  */
 128 #define USTCOMM_REPLY_PADDING1          32
 129 #define USTCOMM_REPLY_PADDING2          32
 130 struct ustcomm_ust_reply {
 131         uint32_t handle;
 132         uint32_t cmd;
 133         int32_t ret_code;       /* enum ustcomm_return_code */
 134         uint32_t ret_val;       /* return value */
 135         char padding[USTCOMM_REPLY_PADDING1];
 136         union {
 137                 struct {
 138                         uint64_t memory_map_size;
 139                 } LTTNG_PACKED channel;
 140                 struct {
 141                         uint64_t memory_map_size;
 142                 } LTTNG_PACKED stream;
 143                 struct lttng_ust_tracer_version version;
 144                 struct lttng_ust_tracepoint_iter tracepoint;
 145                 char padding[USTCOMM_REPLY_PADDING2];
 146         } u;
 147 } LTTNG_PACKED;
 148
 149 struct ustcomm_notify_hdr {
 150         uint32_t notify_cmd;
 151 } LTTNG_PACKED;
 152
 153 #define USTCOMM_NOTIFY_EVENT_MSG_PADDING        24
 154 struct ustcomm_notify_event_msg {
 155         uint32_t session_objd;
 156         uint32_t channel_objd;
 157         char event_name[LTTNG_UST_SYM_NAME_LEN];
 158         int32_t loglevel;
 159         uint32_t signature_len;
 160         uint32_t fields_len;
 161         uint32_t model_emf_uri_len;
 162         uint64_t user_token;
 163         char padding[USTCOMM_NOTIFY_EVENT_MSG_PADDING];
 164         /* followed by signature, fields, model_emf_uri, and key */
 165 } LTTNG_PACKED;
 166
 167 #define USTCOMM_NOTIFY_EVENT_REPLY_PADDING      24
 168 struct ustcomm_notify_event_reply {
 169         int32_t ret_code;       /* 0: ok, negative: error code */
 170         uint32_t event_id;      /* for ring buffer channel events. */
 171         uint64_t counter_index; /* for counter events. */
 172         char padding[USTCOMM_NOTIFY_EVENT_REPLY_PADDING];
 173 } LTTNG_PACKED;
 174
 175 #define USTCOMM_NOTIFY_ENUM_MSG_PADDING         32
 176 struct ustcomm_notify_enum_msg {
 177         uint32_t session_objd;
 178         char enum_name[LTTNG_UST_SYM_NAME_LEN];
 179         uint32_t entries_len;
 180         char padding[USTCOMM_NOTIFY_ENUM_MSG_PADDING];
 181         /* followed by enum entries */
 182 } LTTNG_PACKED;
 183
 184 #define USTCOMM_NOTIFY_ENUM_REPLY_PADDING       32
 185 struct ustcomm_notify_enum_reply {
 186         int32_t ret_code;       /* 0: ok, negative: error code */
 187         uint64_t enum_id;
 188         char padding[USTCOMM_NOTIFY_ENUM_REPLY_PADDING];
 189 } LTTNG_PACKED;
 190
 191 #define USTCOMM_NOTIFY_CHANNEL_MSG_PADDING      32
 192 struct ustcomm_notify_channel_msg {
 193         uint32_t session_objd;
 194         uint32_t channel_objd;
 195         uint32_t ctx_fields_len;
 196         char padding[USTCOMM_NOTIFY_CHANNEL_MSG_PADDING];
 197         /* followed by context fields */
 198 } LTTNG_PACKED;
 199
 200 #define USTCOMM_NOTIFY_CHANNEL_REPLY_PADDING    32
 201 struct ustcomm_notify_channel_reply {
 202         int32_t ret_code;       /* 0: ok, negative: error code */
 203         uint32_t chan_id;
 204         uint32_t header_type;   /* enum ustctl_channel_header */
 205         char padding[USTCOMM_NOTIFY_CHANNEL_REPLY_PADDING];
 206 } LTTNG_PACKED;
 207
 208 /*
 209  * LTTNG_UST_TRACEPOINT_FIELD_LIST reply is followed by a
 210  * struct lttng_ust_field_iter field.
 211  */
 212
 213 extern int ustcomm_create_unix_sock(const char *pathname);
 214 extern int ustcomm_connect_unix_sock(const char *pathname,
 215                 long timeout);
 216 extern int ustcomm_accept_unix_sock(int sock);
 217 extern int ustcomm_listen_unix_sock(int sock);
 218 extern int ustcomm_close_unix_sock(int sock);
 219
 220 extern ssize_t ustcomm_recv_unix_sock(int sock, void *buf, size_t len);
 221 extern ssize_t ustcomm_send_unix_sock(int sock, const void *buf, size_t len);
 222 extern ssize_t ustcomm_send_fds_unix_sock(int sock, int *fds, size_t nb_fd);
 223 extern ssize_t ustcomm_recv_fds_unix_sock(int sock, int *fds, size_t nb_fd);
 224
 225 extern const char *ustcomm_get_readable_code(int code);
 226 extern int ustcomm_send_app_msg(int sock, struct ustcomm_ust_msg *lum);
 227 extern int ustcomm_recv_app_reply(int sock, struct ustcomm_ust_reply *lur,
 228                 uint32_t expected_handle, uint32_t expected_cmd);
 229 extern int ustcomm_send_app_cmd(int sock,
 230                 struct ustcomm_ust_msg *lum,
 231                 struct ustcomm_ust_reply *lur);
 232 int ustcomm_recv_fd(int sock);
 233
 234 ssize_t ustcomm_recv_channel_from_sessiond(int sock,
 235                 void **chan_data, uint64_t len, int *wakeup_fd);
 236 int ustcomm_recv_stream_from_sessiond(int sock,
 237                 uint64_t *memory_map_size,
 238                 int *shm_fd, int *wakeup_fd);
 239 LTTNG_HIDDEN
 240 ssize_t ustcomm_recv_event_notifier_notif_fd_from_sessiond(int sock,
 241                 int *event_notifier_notif_fd);
 242
 243 LTTNG_HIDDEN
 244 ssize_t ustcomm_recv_counter_from_sessiond(int sock,
 245                 void **counter_data, uint64_t len);
 246 LTTNG_HIDDEN
 247 int ustcomm_recv_counter_shm_from_sessiond(int sock,
 248                 int *shm_fd);
 249
 250 /*
 251  * Returns 0 on success, negative error value on error.
 252  * Returns -EPIPE or -ECONNRESET if other end has hung up.
 253  */
 254 int ustcomm_send_reg_msg(int sock,
 255                 enum ustctl_socket_type type,
 256                 uint32_t bits_per_long,
 257                 uint32_t uint8_t_alignment,
 258                 uint32_t uint16_t_alignment,
 259                 uint32_t uint32_t_alignment,
 260                 uint32_t uint64_t_alignment,
 261                 uint32_t long_alignment);
 262
 263 /*
 264  * Returns 0 on success, negative error value on error.
 265  * Returns -EPIPE or -ECONNRESET if other end has hung up.
 266  */
 267 int ustcomm_register_event(int sock,
 268         struct lttng_session *session,
 269         int session_objd,               /* session descriptor */
 270         int channel_objd,               /* channel descriptor */
 271         const char *event_name,         /* event name (input) */
 272         int loglevel,
 273         const char *signature,          /* event signature (input) */
 274         size_t nr_fields,               /* fields */
 275         const struct lttng_event_field *fields,
 276         const char *model_emf_uri,
 277         uint64_t user_token,
 278         uint32_t *event_id,             /* event id (output) */
 279         uint64_t *counter_index);       /* counter index (output) */
 280
 281 /*
 282  * Returns 0 on success, negative error value on error.
 283  * Returns -EPIPE or -ECONNRESET if other end has hung up.
 284  */
 285 int ustcomm_register_enum(int sock,
 286         int session_objd,               /* session descriptor */
 287         const char *enum_name,          /* enum name (input) */
 288         size_t nr_entries,              /* entries */
 289         const struct lttng_enum_entry *entries,
 290         uint64_t *id);                  /* enum id (output) */
 291
 292 /*
 293  * Returns 0 on success, negative error value on error.
 294  * Returns -EPIPE or -ECONNRESET if other end has hung up.
 295  */
 296 int ustcomm_register_channel(int sock,
 297         struct lttng_session *session,
 298         int session_objd,               /* session descriptor */
 299         int channel_objd,               /* channel descriptor */
 300         size_t nr_ctx_fields,
 301         const struct lttng_ctx_field *ctx_fields,
 302         uint32_t *chan_id,              /* channel id (output) */
 303         int *header_type);              /* header type (output) */
 304
 305 int ustcomm_setsockopt_rcv_timeout(int sock, unsigned int msec);
 306 int ustcomm_setsockopt_snd_timeout(int sock, unsigned int msec);
 307
 308 #endif  /* _LTTNG_UST_COMM_H */