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 #include <config.h>
  35
  36 /*
  37  * Default timeout the application waits for the sessiond to send its
  38  * "register done" command. Can be overridden with the environment
  39  * variable "LTTNG_UST_REGISTER_TIMEOUT". Note that if the sessiond is not
  40  * found, the application proceeds directly without any delay.
  41  */
  42 #define LTTNG_UST_DEFAULT_CONSTRUCTOR_TIMEOUT_MS        3000
  43
  44 #define LTTNG_DEFAULT_RUNDIR                            LTTNG_SYSTEM_RUNDIR
  45 #define LTTNG_DEFAULT_HOME_RUNDIR                       ".lttng"
  46
  47 /* Queue size of listen(2) */
  48 #define LTTNG_UST_COMM_MAX_LISTEN                       10
  49 #define LTTNG_UST_COMM_REG_MSG_PADDING                  64
  50
  51 struct lttng_event_field;
  52 struct lttng_ctx_field;
  53
  54 struct ustctl_reg_msg {
  55         uint32_t magic;
  56         uint32_t major;
  57         uint32_t minor;
  58         uint32_t pid;
  59         uint32_t ppid;
  60         uint32_t uid;
  61         uint32_t gid;
  62         uint32_t bits_per_long;
  63         uint32_t uint8_t_alignment;
  64         uint32_t uint16_t_alignment;
  65         uint32_t uint32_t_alignment;
  66         uint32_t uint64_t_alignment;
  67         uint32_t long_alignment;
  68         uint32_t socket_type;                   /* enum ustctl_socket_type */
  69         char name[LTTNG_UST_ABI_PROCNAME_LEN];  /* process name */
  70         char padding[LTTNG_UST_COMM_REG_MSG_PADDING];
  71 } LTTNG_PACKED;
  72
  73 /*
  74  * Data structure for the commands sent from sessiond to UST.
  75  */
  76 #define USTCOMM_MSG_PADDING1            32
  77 #define USTCOMM_MSG_PADDING2            32
  78 struct ustcomm_ust_msg {
  79         uint32_t handle;
  80         uint32_t cmd;
  81         char padding[USTCOMM_MSG_PADDING1];
  82         union {
  83                 struct lttng_ust_channel channel;
  84                 struct lttng_ust_stream stream;
  85                 struct lttng_ust_event event;
  86                 struct lttng_ust_context context;
  87                 struct lttng_ust_tracer_version version;
  88                 struct lttng_ust_tracepoint_iter tracepoint;
  89                 struct {
  90                         uint32_t data_size;     /* following filter data */
  91                         uint32_t reloc_offset;
  92                         uint64_t seqnum;
  93                 } LTTNG_PACKED filter;
  94                 char padding[USTCOMM_MSG_PADDING2];
  95         } u;
  96 } LTTNG_PACKED;
  97
  98 /*
  99  * Data structure for the response from UST to the session daemon.
 100  * cmd_type is sent back in the reply for validation.
 101  */
 102 #define USTCOMM_REPLY_PADDING1          32
 103 #define USTCOMM_REPLY_PADDING2          32
 104 struct ustcomm_ust_reply {
 105         uint32_t handle;
 106         uint32_t cmd;
 107         int32_t ret_code;       /* enum ustcomm_return_code */
 108         uint32_t ret_val;       /* return value */
 109         char padding[USTCOMM_REPLY_PADDING1];
 110         union {
 111                 struct {
 112                         uint64_t memory_map_size;
 113                 } LTTNG_PACKED channel;
 114                 struct {
 115                         uint64_t memory_map_size;
 116                 } LTTNG_PACKED stream;
 117                 struct lttng_ust_tracer_version version;
 118                 struct lttng_ust_tracepoint_iter tracepoint;
 119                 char padding[USTCOMM_REPLY_PADDING2];
 120         } u;
 121 } LTTNG_PACKED;
 122
 123 struct ustcomm_notify_hdr {
 124         uint32_t notify_cmd;
 125 } LTTNG_PACKED;
 126
 127 #define USTCOMM_NOTIFY_EVENT_MSG_PADDING        32
 128 struct ustcomm_notify_event_msg {
 129         uint32_t session_objd;
 130         uint32_t channel_objd;
 131         char event_name[LTTNG_UST_SYM_NAME_LEN];
 132         int32_t loglevel;
 133         uint32_t signature_len;
 134         uint32_t fields_len;
 135         uint32_t model_emf_uri_len;
 136         char padding[USTCOMM_NOTIFY_EVENT_MSG_PADDING];
 137         /* followed by signature, fields, and model_emf_uri */
 138 } LTTNG_PACKED;
 139
 140 #define USTCOMM_NOTIFY_EVENT_REPLY_PADDING      32
 141 struct ustcomm_notify_event_reply {
 142         int32_t ret_code;       /* 0: ok, negative: error code */
 143         uint32_t event_id;
 144         char padding[USTCOMM_NOTIFY_EVENT_REPLY_PADDING];
 145 } LTTNG_PACKED;
 146
 147 #define USTCOMM_NOTIFY_CHANNEL_MSG_PADDING      32
 148 struct ustcomm_notify_channel_msg {
 149         uint32_t session_objd;
 150         uint32_t channel_objd;
 151         uint32_t ctx_fields_len;
 152         char padding[USTCOMM_NOTIFY_CHANNEL_MSG_PADDING];
 153         /* followed by context fields */
 154 } LTTNG_PACKED;
 155
 156 #define USTCOMM_NOTIFY_CHANNEL_REPLY_PADDING    32
 157 struct ustcomm_notify_channel_reply {
 158         int32_t ret_code;       /* 0: ok, negative: error code */
 159         uint32_t chan_id;
 160         uint32_t header_type;   /* enum ustctl_channel_header */
 161         char padding[USTCOMM_NOTIFY_CHANNEL_REPLY_PADDING];
 162 } LTTNG_PACKED;
 163
 164 /*
 165  * LTTNG_UST_TRACEPOINT_FIELD_LIST reply is followed by a
 166  * struct lttng_ust_field_iter field.
 167  */
 168
 169 extern int ustcomm_create_unix_sock(const char *pathname);
 170 extern int ustcomm_connect_unix_sock(const char *pathname);
 171 extern int ustcomm_accept_unix_sock(int sock);
 172 extern int ustcomm_listen_unix_sock(int sock);
 173 extern int ustcomm_close_unix_sock(int sock);
 174
 175 extern ssize_t ustcomm_recv_unix_sock(int sock, void *buf, size_t len);
 176 extern ssize_t ustcomm_send_unix_sock(int sock, const void *buf, size_t len);
 177 extern ssize_t ustcomm_send_fds_unix_sock(int sock, int *fds, size_t nb_fd);
 178 extern ssize_t ustcomm_recv_fds_unix_sock(int sock, int *fds, size_t nb_fd);
 179
 180 extern const char *ustcomm_get_readable_code(int code);
 181 extern int ustcomm_send_app_msg(int sock, struct ustcomm_ust_msg *lum);
 182 extern int ustcomm_recv_app_reply(int sock, struct ustcomm_ust_reply *lur,
 183                 uint32_t expected_handle, uint32_t expected_cmd);
 184 extern int ustcomm_send_app_cmd(int sock,
 185                 struct ustcomm_ust_msg *lum,
 186                 struct ustcomm_ust_reply *lur);
 187 int ustcomm_recv_fd(int sock);
 188
 189 ssize_t ustcomm_recv_channel_from_sessiond(int sock,
 190                 void **chan_data, uint64_t len, int *wakeup_fd);
 191 int ustcomm_recv_stream_from_sessiond(int sock,
 192                 uint64_t *memory_map_size,
 193                 int *shm_fd, int *wakeup_fd);
 194
 195 /*
 196  * Returns 0 on success, negative error value on error.
 197  * Returns -EPIPE or -ECONNRESET if other end has hung up.
 198  */
 199 int ustcomm_send_reg_msg(int sock,
 200                 enum ustctl_socket_type type,
 201                 uint32_t bits_per_long,
 202                 uint32_t uint8_t_alignment,
 203                 uint32_t uint16_t_alignment,
 204                 uint32_t uint32_t_alignment,
 205                 uint32_t uint64_t_alignment,
 206                 uint32_t long_alignment);
 207
 208 /*
 209  * Returns 0 on success, negative error value on error.
 210  * Returns -EPIPE or -ECONNRESET if other end has hung up.
 211  */
 212 int ustcomm_register_event(int sock,
 213         int session_objd,               /* session descriptor */
 214         int channel_objd,               /* channel descriptor */
 215         const char *event_name,         /* event name (input) */
 216         int loglevel,
 217         const char *signature,          /* event signature (input) */
 218         size_t nr_fields,               /* fields */
 219         const struct lttng_event_field *fields,
 220         const char *model_emf_uri,
 221         uint32_t *id);                  /* event id (output) */
 222
 223 /*
 224  * Returns 0 on success, negative error value on error.
 225  * Returns -EPIPE or -ECONNRESET if other end has hung up.
 226  */
 227 int ustcomm_register_channel(int sock,
 228         int session_objd,               /* session descriptor */
 229         int channel_objd,               /* channel descriptor */
 230         size_t nr_ctx_fields,
 231         const struct lttng_ctx_field *ctx_fields,
 232         uint32_t *chan_id,              /* channel id (output) */
 233         int *header_type);              /* header type (output) */
 234
 235 int ustcomm_setsockopt_rcv_timeout(int sock, unsigned int msec);
 236 int ustcomm_setsockopt_snd_timeout(int sock, unsigned int msec);
 237
 238 #endif  /* _LTTNG_UST_COMM_H */