src/lib/lttng-ctl/lttng-ctl-helper.h

   1 /*
   2  * Copyright (C) 2013 David Goulet <dgoulet@efficios.com>
   3  *
   4  * This library is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU Lesser General Public License, version 2.1 only,
   6  * as published by the Free Software Foundation.
   7  *
   8  * This library is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
  11  * for more details.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public License
  14  * along with this library; if not, write to the Free Software Foundation,
  15  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  16  */
  17
  18 #ifndef LTTNG_CTL_HELPER_H
  19 #define LTTNG_CTL_HELPER_H
  20
  21 #include <stdio.h>
  22
  23 #include <common/sessiond-comm/sessiond-comm.h>
  24 #include <lttng/lttng.h>
  25
  26 /*
  27  * NOTE: Every symbol in this helper header MUST be set to hidden so not to
  28  * polute the library name space. Use LTTNG_HIDDEN macro before declaring the
  29  * function in the C file.
  30  */
  31
  32 /* Copy helper functions. */
  33 void lttng_ctl_copy_string(char *dst, const char *src, size_t len);
  34 void lttng_ctl_copy_lttng_domain(struct lttng_domain *dst,
  35                 struct lttng_domain *src);
  36
  37 /*
  38  * Sends the lttcomm message to the session daemon and fills buf if the
  39  * returned data is not NULL.
  40  *
  41  * Return the size of the received data on success or else a negative lttng
  42  * error code. If buf is NULL, 0 is returned on success.
  43  */
  44 int lttng_ctl_ask_sessiond_varlen(struct lttcomm_session_msg *lsm,
  45                 const void *vardata, size_t vardata_len,
  46                 void **user_payload_buf, void **user_cmd_header_buf,
  47                 size_t *user_cmd_header_len);
  48
  49 /*
  50  * Calls lttng_ctl_ask_sessiond_varlen() with no expected command header.
  51  */
  52 static inline
  53 int lttng_ctl_ask_sessiond_varlen_no_cmd_header(struct lttcomm_session_msg *lsm,
  54                 void *vardata, size_t vardata_len, void **user_payload_buf)
  55 {
  56         return lttng_ctl_ask_sessiond_varlen(lsm, vardata,
  57                 vardata_len, user_payload_buf, NULL, NULL);
  58 }
  59
  60 /*
  61  * Use this if no variable length data needs to be sent.
  62  */
  63 static inline
  64 int lttng_ctl_ask_sessiond(struct lttcomm_session_msg *lsm, void **buf)
  65 {
  66         return lttng_ctl_ask_sessiond_varlen_no_cmd_header(lsm, NULL, 0, buf);
  67 }
  68
  69 int lttng_check_tracing_group(void);
  70
  71 #endif /* LTTNG_CTL_HELPER_H */