1 /* $OpenBSD: cmd-pipe-pane.c,v 1.7 2009/11/13 19:53:29 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 #include <sys/socket.h> 21 22 #include <errno.h> 23 #include <fcntl.h> 24 #include <paths.h> 25 #include <string.h> 26 #include <unistd.h> 27 28 #include "tmux.h" 29 30 /* 31 * Open pipe to redirect pane output. If already open, close first. 32 */ 33 34 int cmd_pipe_pane_exec(struct cmd *, struct cmd_ctx *); 35 36 void cmd_pipe_pane_error_callback(struct bufferevent *, short, void *); 37 38 const struct cmd_entry cmd_pipe_pane_entry = { 39 "pipe-pane", "pipep", 40 CMD_TARGET_PANE_USAGE "[-o] [command]", 41 CMD_ARG01, "o", 42 cmd_target_init, 43 cmd_target_parse, 44 cmd_pipe_pane_exec, 45 cmd_target_free, 46 cmd_target_print 47 }; 48 49 int 50 cmd_pipe_pane_exec(struct cmd *self, struct cmd_ctx *ctx) 51 { 52 struct cmd_target_data *data = self->data; 53 struct window_pane *wp; 54 int old_fd, pipe_fd[2], null_fd, mode; 55 56 if (cmd_find_pane(ctx, data->target, NULL, &wp) == NULL) 57 return (-1); 58 59 /* Destroy the old pipe. */ 60 old_fd = wp->pipe_fd; 61 if (wp->pipe_fd != -1) { 62 bufferevent_free(wp->pipe_event); 63 close(wp->pipe_fd); 64 wp->pipe_fd = -1; 65 } 66 67 /* If no pipe command, that is enough. */ 68 if (data->arg == NULL || *data->arg == '\0') 69 return (0); 70 71 /* 72 * With -o, only open the new pipe if there was no previous one. This 73 * allows a pipe to be toggled with a single key, for example: 74 * 75 * bind ^p pipep -o 'cat >>~/output' 76 */ 77 if (cmd_check_flag(data->chflags, 'o') && old_fd != -1) 78 return (0); 79 80 /* Open the new pipe. */ 81 if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe_fd) != 0) { 82 ctx->error(ctx, "socketpair error: %s", strerror(errno)); 83 return (-1); 84 } 85 86 /* Fork the child. */ 87 switch (fork()) { 88 case -1: 89 ctx->error(ctx, "fork error: %s", strerror(errno)); 90 return (-1); 91 case 0: 92 /* Child process. */ 93 close(pipe_fd[0]); 94 server_signal_clear(); 95 96 if (dup2(pipe_fd[1], STDIN_FILENO) == -1) 97 _exit(1); 98 if (pipe_fd[1] != STDIN_FILENO) 99 close(pipe_fd[1]); 100 101 null_fd = open(_PATH_DEVNULL, O_WRONLY, 0); 102 if (dup2(null_fd, STDOUT_FILENO) == -1) 103 _exit(1); 104 if (dup2(null_fd, STDERR_FILENO) == -1) 105 _exit(1); 106 if (null_fd != STDOUT_FILENO && null_fd != STDERR_FILENO) 107 close(null_fd); 108 109 execl(_PATH_BSHELL, "sh", "-c", data->arg, (char *) NULL); 110 _exit(1); 111 default: 112 /* Parent process. */ 113 close(pipe_fd[1]); 114 115 wp->pipe_fd = pipe_fd[0]; 116 wp->pipe_off = EVBUFFER_LENGTH(wp->event->input); 117 118 wp->pipe_event = bufferevent_new(wp->pipe_fd, 119 NULL, NULL, cmd_pipe_pane_error_callback, wp); 120 bufferevent_enable(wp->pipe_event, EV_WRITE); 121 122 if ((mode = fcntl(wp->pipe_fd, F_GETFL)) == -1) 123 fatal("fcntl failed"); 124 if (fcntl(wp->pipe_fd, F_SETFL, mode|O_NONBLOCK) == -1) 125 fatal("fcntl failed"); 126 if (fcntl(wp->pipe_fd, F_SETFD, FD_CLOEXEC) == -1) 127 fatal("fcntl failed"); 128 return (0); 129 } 130 } 131 132 void 133 cmd_pipe_pane_error_callback( 134 unused struct bufferevent *bufev, unused short what, void *data) 135 { 136 struct window_pane *wp = data; 137 138 bufferevent_free(wp->pipe_event); 139 close(wp->pipe_fd); 140 wp->pipe_fd = -1; 141 } 142