include/ust-comm.h

   1 #ifndef _LTTNG_UST_COMM_H
   2 #define _LTTNG_UST_COMM_H
   3
   4 /*
   5  * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
   6  *                      Julien Desfossez <julien.desfossez@polymtl.ca>
   7  *                      Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; only
  12  * version 2.1 of the License.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with this library; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  22  */
  23
  24 /*
  25  * This header is meant for liblttng and libust internal use ONLY.
  26  * These declarations should NOT be considered stable API.
  27  */
  28
  29 #include <limits.h>
  30 #include <unistd.h>
  31 #include <lttng/ust-abi.h>
  32 #include <lttng/ust-error.h>
  33 #include <lttng/ust-compiler.h>
  34
  35 /*
  36  * Default timeout the application waits for the sessiond to send its
  37  * "register done" command. Can be overridden with the environment
  38  * variable "LTTNG_UST_REGISTER_TIMEOUT". Note that if the sessiond is not
  39  * found, the application proceeds directly without any delay.
  40  */
  41 #define LTTNG_UST_DEFAULT_CONSTRUCTOR_TIMEOUT_MS        3000
  42
  43 #define LTTNG_DEFAULT_RUNDIR                            "/var/run/lttng"
  44 #define LTTNG_DEFAULT_HOME_RUNDIR                       ".lttng"
  45
  46 /* Queue size of listen(2) */
  47 #define LTTNG_UST_COMM_MAX_LISTEN                       10
  48 #define LTTNG_UST_COMM_REG_MSG_PADDING                  64
  49
  50 struct lttng_event_field;
  51
  52 struct ustctl_reg_msg {
  53         uint32_t magic;
  54         uint32_t major;
  55         uint32_t minor;
  56         uint32_t pid;
  57         uint32_t ppid;
  58         uint32_t uid;
  59         uint32_t gid;
  60         uint32_t bits_per_long;
  61         uint32_t uint8_t_alignment;
  62         uint32_t uint16_t_alignment;
  63         uint32_t uint32_t_alignment;
  64         uint32_t uint64_t_alignment;
  65         uint32_t long_alignment;
  66         uint32_t socket_type;                   /* enum ustctl_socket_type */
  67         char name[LTTNG_UST_ABI_PROCNAME_LEN];  /* process name */
  68         char padding[LTTNG_UST_COMM_REG_MSG_PADDING];
  69 } LTTNG_PACKED;
  70
  71 /*
  72  * Data structure for the commands sent from sessiond to UST.
  73  */
  74 #define USTCOMM_MSG_PADDING1            32
  75 #define USTCOMM_MSG_PADDING2            32
  76 struct ustcomm_ust_msg {
  77         uint32_t handle;
  78         uint32_t cmd;
  79         char padding[USTCOMM_MSG_PADDING1];
  80         union {
  81                 struct lttng_ust_channel channel;
  82                 struct lttng_ust_stream stream;
  83                 struct lttng_ust_event event;
  84                 struct lttng_ust_context context;
  85                 struct lttng_ust_tracer_version version;
  86                 struct lttng_ust_tracepoint_iter tracepoint;
  87                 struct {
  88                         uint32_t data_size;     /* following filter data */
  89                         uint32_t reloc_offset;
  90                         uint64_t seqnum;
  91                 } LTTNG_PACKED filter;
  92                 char padding[USTCOMM_MSG_PADDING2];
  93         } u;
  94 } LTTNG_PACKED;
  95
  96 /*
  97  * Data structure for the response from UST to the session daemon.
  98  * cmd_type is sent back in the reply for validation.
  99  */
 100 #define USTCOMM_REPLY_PADDING1          32
 101 #define USTCOMM_REPLY_PADDING2          32
 102 struct ustcomm_ust_reply {
 103         uint32_t handle;
 104         uint32_t cmd;
 105         int32_t ret_code;       /* enum ustcomm_return_code */
 106         uint32_t ret_val;       /* return value */
 107         char padding[USTCOMM_REPLY_PADDING1];
 108         union {
 109                 struct {
 110                         uint64_t memory_map_size;
 111                 } LTTNG_PACKED channel;
 112                 struct {
 113                         uint64_t memory_map_size;
 114                 } LTTNG_PACKED stream;
 115                 struct lttng_ust_tracer_version version;
 116                 struct lttng_ust_tracepoint_iter tracepoint;
 117                 char padding[USTCOMM_REPLY_PADDING2];
 118         } u;
 119 } LTTNG_PACKED;
 120
 121 struct ustcomm_notify_hdr {
 122         uint32_t notify_cmd;
 123 } LTTNG_PACKED;
 124
 125 #define USTCOMM_NOTIFY_EVENT_MSG_PADDING        32
 126 struct ustcomm_notify_event_msg {
 127         uint32_t session_objd;
 128         uint32_t channel_objd;
 129         char event_name[LTTNG_UST_SYM_NAME_LEN];
 130         int32_t loglevel;
 131         uint32_t signature_len;
 132         uint32_t fields_len;
 133         uint32_t model_emf_uri_len;
 134         char padding[USTCOMM_NOTIFY_EVENT_MSG_PADDING];
 135         /* followed by signature, fields, and model_emf_uri */
 136 } LTTNG_PACKED;
 137
 138 #define USTCOMM_NOTIFY_EVENT_REPLY_PADDING      32
 139 struct ustcomm_notify_event_reply {
 140         int32_t ret_code;       /* 0: ok, negative: error code */
 141         uint32_t event_id;
 142         char padding[USTCOMM_NOTIFY_EVENT_REPLY_PADDING];
 143 } LTTNG_PACKED;
 144
 145 #define USTCOMM_NOTIFY_CHANNEL_MSG_PADDING      32
 146 struct ustcomm_notify_channel_msg {
 147         uint32_t session_objd;
 148         uint32_t channel_objd;
 149         uint32_t ctx_fields_len;
 150         char padding[USTCOMM_NOTIFY_CHANNEL_MSG_PADDING];
 151         /* followed by context fields */
 152 } LTTNG_PACKED;
 153
 154 #define USTCOMM_NOTIFY_CHANNEL_REPLY_PADDING    32
 155 struct ustcomm_notify_channel_reply {
 156         int32_t ret_code;       /* 0: ok, negative: error code */
 157         uint32_t chan_id;
 158         uint32_t header_type;   /* enum ustctl_channel_header */
 159         char padding[USTCOMM_NOTIFY_CHANNEL_REPLY_PADDING];
 160 } LTTNG_PACKED;
 161
 162 /*
 163  * LTTNG_UST_TRACEPOINT_FIELD_LIST reply is followed by a
 164  * struct lttng_ust_field_iter field.
 165  */
 166
 167 extern int ustcomm_create_unix_sock(const char *pathname);
 168 extern int ustcomm_connect_unix_sock(const char *pathname);
 169 extern int ustcomm_accept_unix_sock(int sock);
 170 extern int ustcomm_listen_unix_sock(int sock);
 171 extern int ustcomm_close_unix_sock(int sock);
 172
 173 extern ssize_t ustcomm_recv_unix_sock(int sock, void *buf, size_t len);
 174 extern ssize_t ustcomm_send_unix_sock(int sock, const void *buf, size_t len);
 175 extern ssize_t ustcomm_send_fds_unix_sock(int sock, int *fds, size_t nb_fd);
 176 extern ssize_t ustcomm_recv_fds_unix_sock(int sock, int *fds, size_t nb_fd);
 177
 178 extern const char *ustcomm_get_readable_code(int code);
 179 extern int ustcomm_send_app_msg(int sock, struct ustcomm_ust_msg *lum);
 180 extern int ustcomm_recv_app_reply(int sock, struct ustcomm_ust_reply *lur,
 181                 uint32_t expected_handle, uint32_t expected_cmd);
 182 extern int ustcomm_send_app_cmd(int sock,
 183                 struct ustcomm_ust_msg *lum,
 184                 struct ustcomm_ust_reply *lur);
 185 int ustcomm_recv_fd(int sock);
 186
 187 ssize_t ustcomm_recv_channel_from_sessiond(int sock,
 188                 void **chan_data, uint64_t len, int *wakeup_fd);
 189 int ustcomm_recv_stream_from_sessiond(int sock,
 190                 uint64_t *memory_map_size,
 191                 int *shm_fd, int *wakeup_fd);
 192
 193 /*
 194  * Returns 0 on success, negative error value on error.
 195  * Returns -EPIPE or -ECONNRESET if other end has hung up.
 196  */
 197 int ustcomm_send_reg_msg(int sock,
 198                 enum ustctl_socket_type type,
 199                 uint32_t bits_per_long,
 200                 uint32_t uint8_t_alignment,
 201                 uint32_t uint16_t_alignment,
 202                 uint32_t uint32_t_alignment,
 203                 uint32_t uint64_t_alignment,
 204                 uint32_t long_alignment);
 205
 206 /*
 207  * Returns 0 on success, negative error value on error.
 208  * Returns -EPIPE or -ECONNRESET if other end has hung up.
 209  */
 210 int ustcomm_register_event(int sock,
 211         int session_objd,               /* session descriptor */
 212         int channel_objd,               /* channel descriptor */
 213         const char *event_name,         /* event name (input) */
 214         int loglevel,
 215         const char *signature,          /* event signature (input) */
 216         size_t nr_fields,               /* fields */
 217         const struct lttng_event_field *fields,
 218         const char *model_emf_uri,
 219         uint32_t *id);                  /* event id (output) */
 220
 221 /*
 222  * Returns 0 on success, negative error value on error.
 223  * Returns -EPIPE or -ECONNRESET if other end has hung up.
 224  */
 225 int ustcomm_register_channel(int sock,
 226         int session_objd,               /* session descriptor */
 227         int channel_objd,               /* channel descriptor */
 228         size_t nr_ctx_fields,
 229         const struct lttng_event_field *ctx_fields,
 230         uint32_t *chan_id,              /* channel id (output) */
 231         int *header_type);              /* header type (output) */
 232
 233 int ustcomm_setsockopt_rcv_timeout(int sock, unsigned int msec);
 234 int ustcomm_setsockopt_snd_timeout(int sock, unsigned int msec);
 235
 236 #endif  /* _LTTNG_UST_COMM_H */