2 * Copyright (C) 2013 David Goulet <dgoulet@efficios.com>
4 * SPDX-License-Identifier: GPL-2.0-only
12 #include <common/macros.h>
13 #include <sys/types.h>
19 enum lttng_pipe_state
{
20 LTTNG_PIPE_STATE_OPENED
= 1,
21 LTTNG_PIPE_STATE_CLOSED
= 2,
25 /* Read: 0, Write: 1. */
28 * Flags of the pipe once opened. pipe(2) specifies either O_NONBLOCK or
29 * O_CLOEXEC can be used. Flags are set using fcntl(2) call.
34 * These states are protected by the operation mutex below.
36 enum lttng_pipe_state r_state
;
37 enum lttng_pipe_state w_state
;
39 /* Held for each read(2) operation. */
40 pthread_mutex_t read_mutex
;
41 /* Held for each write(2) operation. */
42 pthread_mutex_t write_mutex
;
46 * Return 1 if read side is open else 0.
48 static inline int lttng_pipe_is_read_open(const struct lttng_pipe
*pipe
)
50 return pipe
->r_state
== LTTNG_PIPE_STATE_OPENED
? 1 : 0;
54 * Return 1 if write side is open else 0.
56 static inline int lttng_pipe_is_write_open(const struct lttng_pipe
*pipe
)
58 return pipe
->w_state
== LTTNG_PIPE_STATE_OPENED
? 1 : 0;
61 static inline int lttng_pipe_get_readfd(const struct lttng_pipe
*pipe
)
66 static inline int lttng_pipe_get_writefd(const struct lttng_pipe
*pipe
)
71 struct lttng_pipe
*lttng_pipe_open(int flags
);
72 struct lttng_pipe
*lttng_pipe_named_open(const char *path
, mode_t mode
,
74 int lttng_pipe_write_close(struct lttng_pipe
*pipe
);
75 int lttng_pipe_read_close(struct lttng_pipe
*pipe
);
76 /* Close both side of pipe. */
77 int lttng_pipe_close(struct lttng_pipe
*pipe
);
78 void lttng_pipe_destroy(struct lttng_pipe
*pipe
);
80 ssize_t
lttng_pipe_read(struct lttng_pipe
*pipe
, void *buf
, size_t count
);
81 ssize_t
lttng_pipe_write(struct lttng_pipe
*pipe
, const void *buf
,
83 /* Returns and releases the read end of the pipe. */
84 int lttng_pipe_release_readfd(struct lttng_pipe
*pipe
);
85 /* Returns and releases the write end of the pipe. */
86 int lttng_pipe_release_writefd(struct lttng_pipe
*pipe
);
92 #endif /* LTTNG_PIPE_H */