1 /* $OpenBSD$ */
2
3 /*
4 * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
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 <signal.h>
25 #include <stdlib.h>
26 #include <string.h>
27 #include <time.h>
28 #include <unistd.h>
29
30 #include "tmux.h"
31
32 /*
33 * Open pipe to redirect pane output. If already open, close first.
34 */
35
36 static enum cmd_retval cmd_pipe_pane_exec(struct cmd *, struct cmdq_item *);
37
38 static void cmd_pipe_pane_read_callback(struct bufferevent *, void *);
39 static void cmd_pipe_pane_write_callback(struct bufferevent *, void *);
40 static void cmd_pipe_pane_error_callback(struct bufferevent *, short, void *);
41
42 const struct cmd_entry cmd_pipe_pane_entry = {
43 .name = "pipe-pane",
44 .alias = "pipep",
45
46 .args = { "IOot:", 0, 1 },
47 .usage = "[-IOo] " CMD_TARGET_PANE_USAGE " [command]",
48
49 .target = { 't', CMD_FIND_PANE, 0 },
50
51 .flags = CMD_AFTERHOOK,
52 .exec = cmd_pipe_pane_exec
53 };
54
55 static enum cmd_retval
cmd_pipe_pane_exec(struct cmd * self,struct cmdq_item * item)56 cmd_pipe_pane_exec(struct cmd *self, struct cmdq_item *item)
57 {
58 struct args *args = cmd_get_args(self);
59 struct cmd_find_state *target = cmdq_get_target(item);
60 struct client *tc = cmdq_get_target_client(item);
61 struct window_pane *wp = target->wp;
62 struct session *s = target->s;
63 struct winlink *wl = target->wl;
64 struct window_pane_offset *wpo = &wp->pipe_offset;
65 char *cmd;
66 int old_fd, pipe_fd[2], null_fd, in, out;
67 struct format_tree *ft;
68 sigset_t set, oldset;
69
70 /* Destroy the old pipe. */
71 old_fd = wp->pipe_fd;
72 if (wp->pipe_fd != -1) {
73 bufferevent_free(wp->pipe_event);
74 close(wp->pipe_fd);
75 wp->pipe_fd = -1;
76
77 if (window_pane_destroy_ready(wp)) {
78 server_destroy_pane(wp, 1);
79 return (CMD_RETURN_NORMAL);
80 }
81 }
82
83 /* If no pipe command, that is enough. */
84 if (args->argc == 0 || *args->argv[0] == '\0')
85 return (CMD_RETURN_NORMAL);
86
87 /*
88 * With -o, only open the new pipe if there was no previous one. This
89 * allows a pipe to be toggled with a single key, for example:
90 *
91 * bind ^p pipep -o 'cat >>~/output'
92 */
93 if (args_has(args, 'o') && old_fd != -1)
94 return (CMD_RETURN_NORMAL);
95
96 /* What do we want to do? Neither -I or -O is -O. */
97 if (args_has(args, 'I')) {
98 in = 1;
99 out = args_has(args, 'O');
100 } else {
101 in = 0;
102 out = 1;
103 }
104
105 /* Open the new pipe. */
106 if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe_fd) != 0) {
107 cmdq_error(item, "socketpair error: %s", strerror(errno));
108 return (CMD_RETURN_ERROR);
109 }
110
111 /* Expand the command. */
112 ft = format_create(cmdq_get_client(item), item, FORMAT_NONE, 0);
113 format_defaults(ft, tc, s, wl, wp);
114 cmd = format_expand_time(ft, args->argv[0]);
115 format_free(ft);
116
117 /* Fork the child. */
118 sigfillset(&set);
119 sigprocmask(SIG_BLOCK, &set, &oldset);
120 switch (fork()) {
121 case -1:
122 sigprocmask(SIG_SETMASK, &oldset, NULL);
123 cmdq_error(item, "fork error: %s", strerror(errno));
124
125 free(cmd);
126 return (CMD_RETURN_ERROR);
127 case 0:
128 /* Child process. */
129 proc_clear_signals(server_proc, 1);
130 sigprocmask(SIG_SETMASK, &oldset, NULL);
131 close(pipe_fd[0]);
132
133 null_fd = open(_PATH_DEVNULL, O_WRONLY, 0);
134 if (out) {
135 if (dup2(pipe_fd[1], STDIN_FILENO) == -1)
136 _exit(1);
137 } else {
138 if (dup2(null_fd, STDIN_FILENO) == -1)
139 _exit(1);
140 }
141 if (in) {
142 if (dup2(pipe_fd[1], STDOUT_FILENO) == -1)
143 _exit(1);
144 if (pipe_fd[1] != STDOUT_FILENO)
145 close(pipe_fd[1]);
146 } else {
147 if (dup2(null_fd, STDOUT_FILENO) == -1)
148 _exit(1);
149 }
150 if (dup2(null_fd, STDERR_FILENO) == -1)
151 _exit(1);
152 closefrom(STDERR_FILENO + 1);
153
154 execl(_PATH_BSHELL, "sh", "-c", cmd, (char *) NULL);
155 _exit(1);
156 default:
157 /* Parent process. */
158 sigprocmask(SIG_SETMASK, &oldset, NULL);
159 close(pipe_fd[1]);
160
161 wp->pipe_fd = pipe_fd[0];
162 memcpy(wpo, &wp->offset, sizeof *wpo);
163
164 setblocking(wp->pipe_fd, 0);
165 wp->pipe_event = bufferevent_new(wp->pipe_fd,
166 cmd_pipe_pane_read_callback,
167 cmd_pipe_pane_write_callback,
168 cmd_pipe_pane_error_callback,
169 wp);
170 if (wp->pipe_event == NULL)
171 fatalx("out of memory");
172 if (out)
173 bufferevent_enable(wp->pipe_event, EV_WRITE);
174 if (in)
175 bufferevent_enable(wp->pipe_event, EV_READ);
176
177 free(cmd);
178 return (CMD_RETURN_NORMAL);
179 }
180 }
181
182 static void
cmd_pipe_pane_read_callback(__unused struct bufferevent * bufev,void * data)183 cmd_pipe_pane_read_callback(__unused struct bufferevent *bufev, void *data)
184 {
185 struct window_pane *wp = data;
186 struct evbuffer *evb = wp->pipe_event->input;
187 size_t available;
188
189 available = EVBUFFER_LENGTH(evb);
190 log_debug("%%%u pipe read %zu", wp->id, available);
191
192 bufferevent_write(wp->event, EVBUFFER_DATA(evb), available);
193 evbuffer_drain(evb, available);
194
195 if (window_pane_destroy_ready(wp))
196 server_destroy_pane(wp, 1);
197 }
198
199 static void
cmd_pipe_pane_write_callback(__unused struct bufferevent * bufev,void * data)200 cmd_pipe_pane_write_callback(__unused struct bufferevent *bufev, void *data)
201 {
202 struct window_pane *wp = data;
203
204 log_debug("%%%u pipe empty", wp->id);
205
206 if (window_pane_destroy_ready(wp))
207 server_destroy_pane(wp, 1);
208 }
209
210 static void
cmd_pipe_pane_error_callback(__unused struct bufferevent * bufev,__unused short what,void * data)211 cmd_pipe_pane_error_callback(__unused struct bufferevent *bufev,
212 __unused short what, void *data)
213 {
214 struct window_pane *wp = data;
215
216 log_debug("%%%u pipe error", wp->id);
217
218 bufferevent_free(wp->pipe_event);
219 close(wp->pipe_fd);
220 wp->pipe_fd = -1;
221
222 if (window_pane_destroy_ready(wp))
223 server_destroy_pane(wp, 1);
224 }
225