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
  34 /*
  35  * Default timeout the application waits for the sessiond to send its
  36  * "register done" command. Can be overridden with the environment
  37  * variable "LTTNG_UST_REGISTER_TIMEOUT". Note that if the sessiond is not
  38  * found, the application proceeds directly without any delay.
  39  */
  40 #define LTTNG_UST_DEFAULT_CONSTRUCTOR_TIMEOUT_MS        3000
  41
  42 #define LTTNG_RUNDIR                        "/var/run/lttng"
  43 #define LTTNG_HOME_RUNDIR                   "%s/.lttng"
  44
  45 /* Default unix socket path */
  46 #define DEFAULT_GLOBAL_CLIENT_UNIX_SOCK     LTTNG_RUNDIR "/client-lttng-sessiond"
  47 #define DEFAULT_GLOBAL_APPS_UNIX_SOCK       LTTNG_RUNDIR "/apps-lttng-sessiond"
  48 #define DEFAULT_HOME_APPS_UNIX_SOCK         LTTNG_HOME_RUNDIR "/apps-lttng-sessiond"
  49 #define DEFAULT_HOME_CLIENT_UNIX_SOCK       LTTNG_HOME_RUNDIR "/client-lttng-sessiond"
  50
  51 #define DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH   "/lttng-ust-apps-wait"
  52 #define DEFAULT_HOME_APPS_WAIT_SHM_PATH     "/lttng-ust-apps-wait-%u"
  53
  54 /* Queue size of listen(2) */
  55 #define LTTNG_UST_COMM_MAX_LISTEN 10
  56
  57 /*
  58  * Data structure for the commands sent from sessiond to UST.
  59  */
  60 struct ustcomm_ust_msg {
  61         uint32_t handle;
  62         uint32_t cmd;
  63         union {
  64                 struct lttng_ust_channel channel;
  65                 struct lttng_ust_stream stream;
  66                 struct lttng_ust_event event;
  67                 struct lttng_ust_context context;
  68                 struct lttng_ust_tracer_version version;
  69                 struct lttng_ust_tracepoint_iter tracepoint;
  70                 struct {
  71                         uint32_t data_size;     /* following filter data */
  72                         uint32_t reloc_offset;
  73                 } filter;
  74         } u;
  75 };
  76
  77 /*
  78  * Data structure for the response from UST to the session daemon.
  79  * cmd_type is sent back in the reply for validation.
  80  */
  81 struct ustcomm_ust_reply {
  82         uint32_t handle;
  83         uint32_t cmd;
  84         uint32_t ret_code;      /* enum enum ustcomm_return_code */
  85         uint32_t ret_val;       /* return value */
  86         union {
  87                 struct {
  88                         uint64_t memory_map_size;
  89                 } channel;
  90                 struct {
  91                         uint64_t memory_map_size;
  92                 } stream;
  93                 struct lttng_ust_tracer_version version;
  94                 struct lttng_ust_tracepoint_iter tracepoint;
  95         } u;
  96 };
  97
  98 /*
  99  * LTTNG_UST_TRACEPOINT_FIELD_LIST reply is followed by a
 100  * struct lttng_ust_field_iter field.
 101  */
 102
 103 extern int ustcomm_create_unix_sock(const char *pathname);
 104 extern int ustcomm_connect_unix_sock(const char *pathname);
 105 extern int ustcomm_accept_unix_sock(int sock);
 106 extern int ustcomm_listen_unix_sock(int sock);
 107 extern int ustcomm_close_unix_sock(int sock);
 108 /* Send fd(s) over a unix socket. */
 109 extern ssize_t ustcomm_send_fds_unix_sock(int sock, void *buf, int *fds,
 110                 size_t nb_fd, size_t len);
 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 const char *ustcomm_get_readable_code(int code);
 114 extern int ustcomm_send_app_msg(int sock, struct ustcomm_ust_msg *lum);
 115 extern int ustcomm_recv_app_reply(int sock, struct ustcomm_ust_reply *lur,
 116                 uint32_t expected_handle, uint32_t expected_cmd);
 117 extern int ustcomm_send_app_cmd(int sock,
 118                 struct ustcomm_ust_msg *lum,
 119                 struct ustcomm_ust_reply *lur);
 120 int ustcomm_recv_fd(int sock);
 121
 122 #endif  /* _LTTNG_UST_COMM_H */