src/common/kernel-consumer/kernel-consumer.h

   1 /*
   2  * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
   3  * Copyright (C) 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License, version 2 only,
   7  * as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  */
  18
  19 #ifndef _LTTNG_KCONSUMER_H
  20 #define _LTTNG_KCONSUMER_H
  21
  22 #include <common/consumer.h>
  23
  24 /*
  25  * Mmap the ring buffer, read it and write the data to the tracefile.
  26  *
  27  * Returns the number of bytes written, or negative value on error.
  28  */
  29 extern ssize_t lttng_kconsumer_on_read_subbuffer_mmap(
  30                 struct lttng_consumer_local_data *ctx,
  31                 struct lttng_consumer_stream *stream, unsigned long len);
  32
  33 /*
  34  * Splice the data from the ring buffer to the tracefile.
  35  *
  36  * Returns the number of bytes spliced, or negative error value on
  37  * error.
  38  */
  39 extern ssize_t lttng_kconsumer_on_read_subbuffer_splice(
  40                 struct lttng_consumer_local_data *ctx,
  41                 struct lttng_consumer_stream *stream, unsigned long len);
  42
  43 /*
  44  * Take a snapshot for a specific fd
  45  *
  46  * Returns 0 on success, < 0 on error
  47  */
  48 int lttng_kconsumer_take_snapshot(struct lttng_consumer_local_data *ctx,
  49         struct lttng_consumer_stream *stream);
  50
  51 /*
  52  * Get the produced position
  53  *
  54  * Returns 0 on success, < 0 on error
  55  */
  56 int lttng_kconsumer_get_produced_snapshot(
  57         struct lttng_consumer_local_data *ctx,
  58         struct lttng_consumer_stream *stream,
  59         unsigned long *pos);
  60
  61 int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
  62                 int sock, struct pollfd *consumer_sockpoll);
  63
  64
  65 ssize_t lttng_kconsumer_read_subbuffer(struct lttng_consumer_stream *stream,
  66                 struct lttng_consumer_local_data *ctx);
  67 int lttng_kconsumer_on_recv_stream(struct lttng_consumer_stream *stream);
  68
  69 #endif /* _LTTNG_KCONSUMER_H */