| | 1 | /* |
| | 2 | * Copyright (C) 2013 - David Goulet <dgoulet@efficios.com> |
| | 3 | * |
| | 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. |
| | 7 | * |
| | 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 |
| | 11 | * more details. |
| | 12 | * |
| | 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. |
| | 16 | */ |
| | 17 | |
| | 18 | #ifndef LTTNG_PIPE_H |
| | 19 | #define LTTNG_PIPE_H |
| | 20 | |
| | 21 | #include <pthread.h> |
| | 22 | #include <common/macros.h> |
| | 23 | #include <sys/types.h> |
| | 24 | |
| | 25 | enum lttng_pipe_state { |
| | 26 | LTTNG_PIPE_STATE_OPENED = 1, |
| | 27 | LTTNG_PIPE_STATE_CLOSED = 2, |
| | 28 | }; |
| | 29 | |
| | 30 | struct lttng_pipe { |
| | 31 | /* Read: 0, Write: 1. */ |
| | 32 | int fd[2]; |
| | 33 | /* |
| | 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. |
| | 36 | */ |
| | 37 | int flags; |
| | 38 | |
| | 39 | /* |
| | 40 | * These states are protected by the operation mutex below. |
| | 41 | */ |
| | 42 | enum lttng_pipe_state r_state; |
| | 43 | enum lttng_pipe_state w_state; |
| | 44 | |
| | 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; |
| | 49 | }; |
| | 50 | |
| | 51 | /* |
| | 52 | * Return 1 if read side is open else 0. |
| | 53 | */ |
| | 54 | static inline int lttng_pipe_is_read_open(const struct lttng_pipe *pipe) |
| | 55 | { |
| | 56 | return pipe->r_state == LTTNG_PIPE_STATE_OPENED ? 1 : 0; |
| | 57 | } |
| | 58 | |
| | 59 | /* |
| | 60 | * Return 1 if write side is open else 0. |
| | 61 | */ |
| | 62 | static inline int lttng_pipe_is_write_open(const struct lttng_pipe *pipe) |
| | 63 | { |
| | 64 | return pipe->w_state == LTTNG_PIPE_STATE_OPENED ? 1 : 0; |
| | 65 | } |
| | 66 | |
| | 67 | static inline int lttng_pipe_get_readfd(const struct lttng_pipe *pipe) |
| | 68 | { |
| | 69 | return pipe->fd[0]; |
| | 70 | } |
| | 71 | |
| | 72 | static inline int lttng_pipe_get_writefd(const struct lttng_pipe *pipe) |
| | 73 | { |
| | 74 | return pipe->fd[1]; |
| | 75 | } |
| | 76 | |
| | 77 | LTTNG_HIDDEN |
| | 78 | struct lttng_pipe *lttng_pipe_open(int flags); |
| | 79 | LTTNG_HIDDEN |
| | 80 | struct lttng_pipe *lttng_pipe_named_open(const char *path, mode_t mode, |
| | 81 | int flags); |
| | 82 | LTTNG_HIDDEN |
| | 83 | int lttng_pipe_write_close(struct lttng_pipe *pipe); |
| | 84 | LTTNG_HIDDEN |
| | 85 | int lttng_pipe_read_close(struct lttng_pipe *pipe); |
| | 86 | /* Close both side of pipe. */ |
| | 87 | LTTNG_HIDDEN |
| | 88 | int lttng_pipe_close(struct lttng_pipe *pipe); |
| | 89 | LTTNG_HIDDEN |
| | 90 | void lttng_pipe_destroy(struct lttng_pipe *pipe); |
| | 91 | |
| | 92 | LTTNG_HIDDEN |
| | 93 | ssize_t lttng_pipe_read(struct lttng_pipe *pipe, void *buf, size_t count); |
| | 94 | LTTNG_HIDDEN |
| | 95 | ssize_t lttng_pipe_write(struct lttng_pipe *pipe, const void *buf, |
| | 96 | size_t count); |
| | 97 | /* Returns and releases the read end of the pipe. */ |
| | 98 | LTTNG_HIDDEN |
| | 99 | int lttng_pipe_release_readfd(struct lttng_pipe *pipe); |
| | 100 | /* Returns and releases the write end of the pipe. */ |
| | 101 | LTTNG_HIDDEN |
| | 102 | int lttng_pipe_release_writefd(struct lttng_pipe *pipe); |
| | 103 | |
| | 104 | #endif /* LTTNG_PIPE_H */ |
projects / lttng-tools.git / blame_incremental