include/lttng/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 program is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License
  11  * as published by the Free Software Foundation; only version 2
  12  * of the License.
  13  *
  14  * This program 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
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, 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
  33 /*
  34  * Default timeout the application waits for the sessiond to send its
  35  * "register done" command. Can be overridden with the environment
  36  * variable "LTTNG_UST_REGISTER_TIMEOUT". Note that if the sessiond is not
  37  * found, the application proceeds directly without any delay.
  38  */
  39 #define LTTNG_UST_DEFAULT_CONSTRUCTOR_TIMEOUT_MS        3000
  40
  41 #define LTTNG_RUNDIR                        "/var/run/lttng"
  42
  43 /* Default unix socket path */
  44 #define DEFAULT_GLOBAL_CLIENT_UNIX_SOCK     LTTNG_RUNDIR "/client-lttng-sessiond"
  45 #define DEFAULT_GLOBAL_APPS_UNIX_SOCK       LTTNG_RUNDIR "/apps-lttng-sessiond"
  46 #define DEFAULT_HOME_APPS_UNIX_SOCK         "%s/.apps-lttng-sessiond"
  47 #define DEFAULT_HOME_CLIENT_UNIX_SOCK       "%s/.client-lttng-sessiond"
  48
  49 #define DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH   "/lttng-ust-apps-wait"
  50 #define DEFAULT_HOME_APPS_WAIT_SHM_PATH     "/lttng-ust-apps-wait-%u"
  51
  52 /* Queue size of listen(2) */
  53 #define LTTNG_UST_COMM_MAX_LISTEN 10
  54
  55 /* Get the error code index from 0. USTCOMM_ERR starts at 1000.
  56  */
  57 #define USTCOMM_ERR_INDEX(code) (code - USTCOMM_ERR)
  58
  59 /*
  60  * ustcomm error code.
  61  */
  62 enum ustcomm_return_code {
  63         USTCOMM_OK = 0,                                 /* Ok */
  64         /* Range 1 to 999 used for standard error numbers (errno.h) */
  65         USTCOMM_ERR = 1000,                             /* Unknown Error */
  66         USTCOMM_UND,                                    /* Undefine command */
  67         USTCOMM_NOT_IMPLEMENTED,        /* Command not implemented */
  68         USTCOMM_UNKNOWN_DOMAIN,         /* Tracing domain not known */
  69         USTCOMM_ALLOC_FAIL,                             /* Trace allocation fail */
  70         USTCOMM_NO_SESSION,                             /* No session found */
  71         USTCOMM_CREATE_FAIL,                    /* Create trace fail */
  72         USTCOMM_SESSION_FAIL,                   /* Create session fail */
  73         USTCOMM_START_FAIL,                             /* Start tracing fail */
  74         USTCOMM_STOP_FAIL,                              /* Stop tracing fail */
  75         USTCOMM_LIST_FAIL,                              /* Listing apps fail */
  76         USTCOMM_NO_APPS,                                /* No traceable application */
  77         USTCOMM_SESS_NOT_FOUND,                 /* Session name not found */
  78         USTCOMM_NO_TRACE,                               /* No trace exist */
  79         USTCOMM_FATAL,                                  /* Session daemon had a fatal error */
  80         USTCOMM_NO_TRACEABLE,                   /* Error for non traceable app */
  81         USTCOMM_SELECT_SESS,                    /* Must select a session */
  82         USTCOMM_EXIST_SESS,                             /* Session name already exist */
  83         USTCOMM_NO_EVENT,                               /* No event found */
  84         USTCOMM_KERN_NA,                                /* Kernel tracer unavalable */
  85         USTCOMM_KERN_EVENT_EXIST,       /* Kernel event already exists */
  86         USTCOMM_KERN_SESS_FAIL,                 /* Kernel create session failed */
  87         USTCOMM_KERN_CHAN_FAIL,                 /* Kernel create channel failed */
  88         USTCOMM_KERN_CHAN_NOT_FOUND,    /* Kernel channel not found */
  89         USTCOMM_KERN_CHAN_DISABLE_FAIL, /* Kernel disable channel failed */
  90         USTCOMM_KERN_CHAN_ENABLE_FAIL,  /* Kernel enable channel failed */
  91         USTCOMM_KERN_CONTEXT_FAIL,      /* Kernel add context failed */
  92         USTCOMM_KERN_ENABLE_FAIL,               /* Kernel enable event failed */
  93         USTCOMM_KERN_DISABLE_FAIL,              /* Kernel disable event failed */
  94         USTCOMM_KERN_META_FAIL,                 /* Kernel open metadata failed */
  95         USTCOMM_KERN_START_FAIL,                /* Kernel start trace failed */
  96         USTCOMM_KERN_STOP_FAIL,                 /* Kernel stop trace failed */
  97         USTCOMM_KERN_CONSUMER_FAIL,             /* Kernel consumer start failed */
  98         USTCOMM_KERN_STREAM_FAIL,               /* Kernel create stream failed */
  99         USTCOMM_KERN_DIR_FAIL,                  /* Kernel trace directory creation failed */
 100         USTCOMM_KERN_DIR_EXIST,                 /* Kernel trace directory exist */
 101         USTCOMM_KERN_NO_SESSION,                /* No kernel session found */
 102         USTCOMM_KERN_LIST_FAIL,                 /* Kernel listing events failed */
 103         USTCONSUMER_COMMAND_SOCK_READY, /* when kconsumerd command socket ready */
 104         USTCONSUMER_SUCCESS_RECV_FD,            /* success on receiving fds */
 105         USTCONSUMER_ERROR_RECV_FD,              /* error on receiving fds */
 106         USTCONSUMER_POLL_ERROR,                 /* Error in polling thread in kconsumerd */
 107         USTCONSUMER_POLL_NVAL,                  /* Poll on closed fd */
 108         USTCONSUMER_POLL_HUP,                   /* All fds have hungup */
 109         USTCONSUMER_EXIT_SUCCESS,               /* kconsumerd exiting normally */
 110         USTCONSUMER_EXIT_FAILURE,               /* kconsumerd exiting on error */
 111         USTCONSUMER_OUTFD_ERROR,                        /* error opening the tracefile */
 112         USTCONSUMER_SPLICE_EBADF,               /* EBADF from splice(2) */
 113         USTCONSUMER_SPLICE_EINVAL,              /* EINVAL from splice(2) */
 114         USTCONSUMER_SPLICE_ENOMEM,              /* ENOMEM from splice(2) */
 115         USTCONSUMER_SPLICE_ESPIPE,              /* ESPIPE from splice(2) */
 116         /* MUST be last element */
 117         USTCOMM_NR,                                             /* Last element */
 118 };
 119
 120 /*
 121  * Data structure for the commands sent from sessiond to UST.
 122  */
 123 struct ustcomm_ust_msg {
 124         uint32_t handle;
 125         uint32_t cmd;
 126         union {
 127                 struct lttng_ust_channel channel;
 128                 struct lttng_ust_stream stream;
 129                 struct lttng_ust_event event;
 130                 struct lttng_ust_context context;
 131                 struct lttng_ust_tracer_version version;
 132                 char tracepoint_list_entry[LTTNG_UST_SYM_NAME_LEN];
 133         } u;
 134 };
 135
 136 /*
 137  * Data structure for the response from UST to the session daemon.
 138  * cmd_type is sent back in the reply for validation.
 139  */
 140 struct ustcomm_ust_reply {
 141         uint32_t handle;
 142         uint32_t cmd;
 143         uint32_t ret_code;      /* enum enum ustcomm_return_code */
 144         uint32_t ret_val;       /* return value */
 145         union {
 146                 struct {
 147                         uint64_t memory_map_size;
 148                 } channel;
 149                 struct {
 150                         uint64_t memory_map_size;
 151                 } stream;
 152                 struct lttng_ust_tracer_version version;
 153                 char tracepoint_list_entry[LTTNG_UST_SYM_NAME_LEN];
 154         } u;
 155 };
 156
 157 extern int ustcomm_create_unix_sock(const char *pathname);
 158 extern int ustcomm_connect_unix_sock(const char *pathname);
 159 extern int ustcomm_accept_unix_sock(int sock);
 160 extern int ustcomm_listen_unix_sock(int sock);
 161 extern int ustcomm_close_unix_sock(int sock);
 162 /* Send fd(s) over a unix socket. */
 163 extern ssize_t ustcomm_send_fds_unix_sock(int sock, void *buf, int *fds,
 164                 size_t nb_fd, size_t len);
 165 extern ssize_t ustcomm_recv_unix_sock(int sock, void *buf, size_t len);
 166 extern ssize_t ustcomm_send_unix_sock(int sock, void *buf, size_t len);
 167 extern const char *ustcomm_get_readable_code(int code);
 168 extern int ustcomm_send_app_msg(int sock, struct ustcomm_ust_msg *lum);
 169 extern int ustcomm_recv_app_reply(int sock, struct ustcomm_ust_reply *lur,
 170                 uint32_t expected_handle, uint32_t expected_cmd);
 171 extern int ustcomm_send_app_cmd(int sock,
 172                 struct ustcomm_ust_msg *lum,
 173                 struct ustcomm_ust_reply *lur);
 174 int ustcomm_recv_fd(int sock);
 175
 176 #endif  /* _LTTNG_UST_COMM_H */