1 /* $OpenBSD: cmd-pipe-pane.c,v 1.2 2009/10/21 18:12:31 nicm Exp $ */ 2 3 /* 4 * Copyright (c) 2009 Nicholas Marriott <nicm@users.sourceforge.net> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER 15 * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING 16 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 #include <sys/types.h> 20 21 #include <errno.h> 22 #include <fcntl.h> 23 #include <paths.h> 24 #include <string.h> 25 #include <unistd.h> 26 27 #include "tmux.h" 28 29 /* 30 * Open pipe to redirect pane output. If already open, close first. 31 */ 32 33 int cmd_pipe_pane_exec(struct cmd *, struct cmd_ctx *); 34 35 const struct cmd_entry cmd_pipe_pane_entry = { 36 "pipe-pane", "pipep", 37 CMD_TARGET_PANE_USAGE "[-o] [command]", 38 CMD_ARG01, CMD_CHFLAG('o'), 39 cmd_target_init, 40 cmd_target_parse, 41 cmd_pipe_pane_exec, 42 cmd_target_free, 43 cmd_target_print 44 }; 45 46 int 47 cmd_pipe_pane_exec(struct cmd *self, struct cmd_ctx *ctx) 48 { 49 struct cmd_target_data *data = self->data; 50 struct window_pane *wp; 51 int old_fd, pipe_fd[2], null_fd, mode; 52 53 if (cmd_find_pane(ctx, data->target, NULL, &wp) == NULL) 54 return (-1); 55 56 /* Destroy the old pipe. */ 57 old_fd = wp->pipe_fd; 58 if (wp->pipe_fd != -1) { 59 buffer_destroy(wp->pipe_buf); 60 close(wp->pipe_fd); 61 wp->pipe_fd = -1; 62 } 63 64 /* If no pipe command, that is enough. */ 65 if (data->arg == NULL || *data->arg == '\0') 66 return (0); 67 68 /* 69 * With -o, only open the new pipe if there was no previous one. This 70 * allows a pipe to be toggled with a single key, for example: 71 * 72 * bind ^p pipep -o 'cat >>~/output' 73 */ 74 if (data->chflags & CMD_CHFLAG('o') && old_fd != -1) 75 return (0); 76 77 /* Open the new pipe. */ 78 if (pipe(pipe_fd) != 0) { 79 ctx->error(ctx, "pipe error: %s", strerror(errno)); 80 return (-1); 81 } 82 83 /* Fork the child. */ 84 switch (fork()) { 85 case -1: 86 ctx->error(ctx, "fork error: %s", strerror(errno)); 87 return (-1); 88 case 0: 89 /* Child process. */ 90 close(pipe_fd[0]); 91 sigreset(); 92 93 if (dup2(pipe_fd[1], STDIN_FILENO) == -1) 94 _exit(1); 95 if (pipe_fd[1] != STDIN_FILENO) 96 close(pipe_fd[1]); 97 98 null_fd = open(_PATH_DEVNULL, O_WRONLY, 0); 99 if (dup2(null_fd, STDOUT_FILENO) == -1) 100 _exit(1); 101 if (dup2(null_fd, STDERR_FILENO) == -1) 102 _exit(1); 103 if (null_fd != STDOUT_FILENO && null_fd != STDERR_FILENO) 104 close(null_fd); 105 106 execl(_PATH_BSHELL, "sh", "-c", data->arg, (char *) NULL); 107 _exit(1); 108 default: 109 /* Parent process. */ 110 close(pipe_fd[1]); 111 112 wp->pipe_fd = pipe_fd[0]; 113 wp->pipe_buf = buffer_create(BUFSIZ); 114 wp->pipe_off = BUFFER_USED(wp->in); 115 116 if ((mode = fcntl(wp->pipe_fd, F_GETFL)) == -1) 117 fatal("fcntl failed"); 118 if (fcntl(wp->pipe_fd, F_SETFL, mode|O_NONBLOCK) == -1) 119 fatal("fcntl failed"); 120 if (fcntl(wp->pipe_fd, F_SETFD, FD_CLOEXEC) == -1) 121 fatal("fcntl failed"); 122 return (0); 123 } 124 125 return (0); 126 } 127