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_RUNDIR                        "/var/run/lttng"
  44 #define LTTNG_HOME_RUNDIR                   "%s/.lttng"
  45
  46 /* Default unix socket path */
  47 #define DEFAULT_GLOBAL_CLIENT_UNIX_SOCK     LTTNG_RUNDIR "/client-lttng-sessiond"
  48 #define DEFAULT_GLOBAL_APPS_UNIX_SOCK       LTTNG_RUNDIR "/apps-lttng-sessiond"
  49 #define DEFAULT_HOME_APPS_UNIX_SOCK         LTTNG_HOME_RUNDIR "/apps-lttng-sessiond"
  50 #define DEFAULT_HOME_CLIENT_UNIX_SOCK       LTTNG_HOME_RUNDIR "/client-lttng-sessiond"
  51
  52 #define DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH   "/lttng-ust-apps-wait"
  53 #define DEFAULT_HOME_APPS_WAIT_SHM_PATH     "/lttng-ust-apps-wait-%u"
  54
  55 /* Queue size of listen(2) */
  56 #define LTTNG_UST_COMM_MAX_LISTEN 10
  57
  58 /*
  59  * Data structure for the commands sent from sessiond to UST.
  60  */
  61 struct ustcomm_ust_msg {
  62         uint32_t handle;
  63         uint32_t cmd;
  64         union {
  65                 struct lttng_ust_channel channel;
  66                 struct lttng_ust_stream stream;
  67                 struct lttng_ust_event event;
  68                 struct lttng_ust_context context;
  69                 struct lttng_ust_tracer_version version;
  70                 struct lttng_ust_tracepoint_iter tracepoint;
  71                 struct {
  72                         uint32_t data_size;     /* following filter data */
  73                         uint32_t reloc_offset;
  74                         uint64_t seqnum;
  75                 } LTTNG_PACKED filter;
  76         } u;
  77 } LTTNG_PACKED;
  78
  79 /*
  80  * Data structure for the response from UST to the session daemon.
  81  * cmd_type is sent back in the reply for validation.
  82  */
  83 struct ustcomm_ust_reply {
  84         uint32_t handle;
  85         uint32_t cmd;
  86         uint32_t ret_code;      /* enum enum ustcomm_return_code */
  87         uint32_t ret_val;       /* return value */
  88         union {
  89                 struct {
  90                         uint64_t memory_map_size;
  91                 } LTTNG_PACKED channel;
  92                 struct {
  93                         uint64_t memory_map_size;
  94                 } LTTNG_PACKED stream;
  95                 struct lttng_ust_tracer_version version;
  96                 struct lttng_ust_tracepoint_iter tracepoint;
  97         } u;
  98 } LTTNG_PACKED;
  99
 100 /*
 101  * LTTNG_UST_TRACEPOINT_FIELD_LIST reply is followed by a
 102  * struct lttng_ust_field_iter field.
 103  */
 104
 105 extern int ustcomm_create_unix_sock(const char *pathname);
 106 extern int ustcomm_connect_unix_sock(const char *pathname);
 107 extern int ustcomm_accept_unix_sock(int sock);
 108 extern int ustcomm_listen_unix_sock(int sock);
 109 extern int ustcomm_close_unix_sock(int sock);
 110
 111 extern ssize_t ustcomm_recv_unix_sock(int sock, void *buf, size_t len);
 112 extern ssize_t ustcomm_send_unix_sock(int sock, void *buf, size_t len);
 113 extern ssize_t ustcomm_send_fds_unix_sock(int sock, int *fds, size_t nb_fd);
 114 extern ssize_t ustcomm_recv_fds_unix_sock(int sock, int *fds, size_t nb_fd);
 115
 116 extern const char *ustcomm_get_readable_code(int code);
 117 extern int ustcomm_send_app_msg(int sock, struct ustcomm_ust_msg *lum);
 118 extern int ustcomm_recv_app_reply(int sock, struct ustcomm_ust_reply *lur,
 119                 uint32_t expected_handle, uint32_t expected_cmd);
 120 extern int ustcomm_send_app_cmd(int sock,
 121                 struct ustcomm_ust_msg *lum,
 122                 struct ustcomm_ust_reply *lur);
 123 int ustcomm_recv_fd(int sock);
 124
 125 ssize_t ustcomm_recv_channel_from_sessiond(int sock,
 126                 void **chan_data, uint64_t len);
 127 int ustcomm_recv_stream_from_sessiond(int sock,
 128                 uint64_t *memory_map_size,
 129                 int *shm_fd, int *wakeup_fd);
 130
 131 #endif  /* _LTTNG_UST_COMM_H */