2 * Copyright (C) 2013 - David Goulet <dgoulet@efficios.com>
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License, version 2 only, as
6 * published by the Free Software Foundation.
8 * This program 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 General Public License for
13 * You should have received a copy of the GNU General Public License along with
14 * this program; if not, write to the Free Software Foundation, Inc., 51
15 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
22 #include <common/macros.h>
23 #include <sys/types.h>
25 enum lttng_pipe_state
{
26 LTTNG_PIPE_STATE_OPENED
= 1,
27 LTTNG_PIPE_STATE_CLOSED
= 2,
31 /* Read: 0, Write: 1. */
34 * Flags of the pipe once opened. pipe(2) specifies either O_NONBLOCK or
35 * O_CLOEXEC can be used. Flags are set using fcntl(2) call.
40 * These states are protected by the operation mutex below.
42 enum lttng_pipe_state r_state
;
43 enum lttng_pipe_state w_state
;
45 /* Held for each read(2) operation. */
46 pthread_mutex_t read_mutex
;
47 /* Held for each write(2) operation. */
48 pthread_mutex_t write_mutex
;
52 * Return 1 if read side is open else 0.
54 static inline int lttng_pipe_is_read_open(const struct lttng_pipe
*pipe
)
56 return pipe
->r_state
== LTTNG_PIPE_STATE_OPENED
? 1 : 0;
60 * Return 1 if write side is open else 0.
62 static inline int lttng_pipe_is_write_open(const struct lttng_pipe
*pipe
)
64 return pipe
->w_state
== LTTNG_PIPE_STATE_OPENED
? 1 : 0;
67 static inline int lttng_pipe_get_readfd(const struct lttng_pipe
*pipe
)
72 static inline int lttng_pipe_get_writefd(const struct lttng_pipe
*pipe
)
78 struct lttng_pipe
*lttng_pipe_open(int flags
);
80 struct lttng_pipe
*lttng_pipe_named_open(const char *path
, mode_t mode
,
83 int lttng_pipe_write_close(struct lttng_pipe
*pipe
);
85 int lttng_pipe_read_close(struct lttng_pipe
*pipe
);
86 /* Close both side of pipe. */
88 int lttng_pipe_close(struct lttng_pipe
*pipe
);
90 void lttng_pipe_destroy(struct lttng_pipe
*pipe
);
93 ssize_t
lttng_pipe_read(struct lttng_pipe
*pipe
, void *buf
, size_t count
);
95 ssize_t
lttng_pipe_write(struct lttng_pipe
*pipe
, const void *buf
,
97 /* Returns and releases the read end of the pipe. */
99 int lttng_pipe_release_readfd(struct lttng_pipe
*pipe
);
100 /* Returns and releases the write end of the pipe. */
102 int lttng_pipe_release_writefd(struct lttng_pipe
*pipe
);
104 #endif /* LTTNG_PIPE_H */