Annotation of src/usr.bin/tmux/client.c, Revision 1.49
1.49 ! nicm 1: /* $OpenBSD: client.c,v 1.48 2011/03/03 08:51:47 nicm Exp $ */
1.1 nicm 2:
3: /*
4: * Copyright (c) 2007 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: #include <sys/stat.h>
22: #include <sys/un.h>
23: #include <sys/wait.h>
24:
25: #include <errno.h>
1.30 nicm 26: #include <event.h>
1.1 nicm 27: #include <fcntl.h>
28: #include <pwd.h>
29: #include <stdlib.h>
30: #include <string.h>
31: #include <unistd.h>
32:
33: #include "tmux.h"
34:
1.25 nicm 35: struct imsgbuf client_ibuf;
1.30 nicm 36: struct event client_event;
1.25 nicm 37: const char *client_exitmsg;
1.32 nicm 38: int client_exitval;
1.48 nicm 39: enum msgtype client_exittype;
1.46 nicm 40: int client_attached;
1.1 nicm 41:
1.49 ! nicm 42: int client_get_lock(char *);
1.46 nicm 43: int client_connect(char *, int);
1.30 nicm 44: void client_send_identify(int);
45: void client_send_environ(void);
46: void client_write_server(enum msgtype, void *, size_t);
1.31 nicm 47: void client_update_event(void);
1.30 nicm 48: void client_signal(int, short, void *);
49: void client_callback(int, short, void *);
1.46 nicm 50: int client_dispatch_attached(void);
51: int client_dispatch_wait(void *);
1.25 nicm 52:
1.49 ! nicm 53: /*
! 54: * Get server create lock. If already held then server start is happening in
! 55: * another client, so block until the lock is released and return -1 to
! 56: * retry. Ignore other errors - just continue and start the server without the
! 57: * lock.
! 58: */
! 59: int
! 60: client_get_lock(char *lockfile)
! 61: {
! 62: int lockfd;
! 63:
! 64: if ((lockfd = open(lockfile, O_WRONLY|O_CREAT, 0600)) == -1)
! 65: fatal("open failed");
! 66:
! 67: if (flock(lockfd, LOCK_EX|LOCK_NB) == -1 && errno == EWOULDBLOCK) {
! 68: while (flock(lockfd, LOCK_EX) == -1 && errno == EINTR)
! 69: /* nothing */;
! 70: close(lockfd);
! 71: return (-1);
! 72: }
! 73:
! 74: return (lockfd);
! 75: }
! 76:
1.46 nicm 77: /* Connect client to server. */
78: int
79: client_connect(char *path, int start_server)
1.1 nicm 80: {
1.26 nicm 81: struct sockaddr_un sa;
82: size_t size;
1.49 ! nicm 83: int fd, lockfd;
! 84: char *lockfile;
1.1 nicm 85:
86: memset(&sa, 0, sizeof sa);
87: sa.sun_family = AF_UNIX;
88: size = strlcpy(sa.sun_path, path, sizeof sa.sun_path);
89: if (size >= sizeof sa.sun_path) {
90: errno = ENAMETOOLONG;
1.46 nicm 91: return (-1);
1.1 nicm 92: }
93:
1.49 ! nicm 94: retry:
1.10 nicm 95: if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
1.18 nicm 96: fatal("socket failed");
1.1 nicm 97:
1.10 nicm 98: if (connect(fd, (struct sockaddr *) &sa, SUN_LEN(&sa)) == -1) {
1.49 ! nicm 99: if (errno != ECONNREFUSED && errno != ENOENT)
! 100: goto failed;
1.46 nicm 101: if (!start_server)
102: goto failed;
1.49 ! nicm 103: close(fd);
! 104:
! 105: xasprintf(&lockfile, "%s.lock", path);
! 106: if ((lockfd = client_get_lock(lockfile)) == -1)
! 107: goto retry;
! 108: if (unlink(path) != 0 && errno != ENOENT)
! 109: return (-1);
! 110: fd = server_start(lockfd, lockfile);
! 111: xfree(lockfile);
! 112: close(lockfd);
1.1 nicm 113: }
114:
1.47 nicm 115: setblocking(fd, 0);
1.46 nicm 116: return (fd);
117:
118: failed:
119: close(fd);
120: return (-1);
121: }
122:
123: /* Client main loop. */
124: int
125: client_main(int argc, char **argv, int flags)
126: {
127: struct cmd *cmd;
128: struct cmd_list *cmdlist;
129: struct msg_command_data cmddata;
130: int cmdflags, fd;
1.48 nicm 131: pid_t ppid;
1.46 nicm 132: enum msgtype msg;
133: char *cause;
134:
135: /* Set up the initial command. */
136: cmdflags = 0;
137: if (shell_cmd != NULL) {
138: msg = MSG_SHELL;
139: cmdflags = CMD_STARTSERVER;
140: } else if (argc == 0) {
141: msg = MSG_COMMAND;
142: cmdflags = CMD_STARTSERVER|CMD_SENDENVIRON|CMD_CANTNEST;
143: } else {
144: msg = MSG_COMMAND;
145:
146: /*
147: * It sucks parsing the command string twice (in client and
148: * later in server) but it is necessary to get the start server
149: * flag.
150: */
151: if ((cmdlist = cmd_list_parse(argc, argv, &cause)) == NULL) {
152: log_warnx("%s", cause);
153: return (1);
154: }
155: cmdflags &= ~CMD_STARTSERVER;
156: TAILQ_FOREACH(cmd, &cmdlist->list, qentry) {
157: if (cmd->entry->flags & CMD_STARTSERVER)
158: cmdflags |= CMD_STARTSERVER;
159: if (cmd->entry->flags & CMD_SENDENVIRON)
160: cmdflags |= CMD_SENDENVIRON;
161: if (cmd->entry->flags & CMD_CANTNEST)
162: cmdflags |= CMD_CANTNEST;
163: }
164: cmd_list_free(cmdlist);
165: }
166:
167: /*
168: * Check if this could be a nested session, if the command can't nest:
169: * if the socket path matches $TMUX, this is probably the same server.
170: */
171: if (shell_cmd == NULL && environ_path != NULL &&
172: cmdflags & CMD_CANTNEST && strcmp(socket_path, environ_path) == 0) {
173: log_warnx("sessions should be nested with care. "
174: "unset $TMUX to force.");
175: return (1);
176: }
177:
178: /* Initialise the client socket and start the server. */
179: fd = client_connect(socket_path, cmdflags & CMD_STARTSERVER);
180: if (fd == -1) {
181: log_warn("failed to connect to server");
182: return (1);
183: }
184:
185: /* Set process title, log and signals now this is the client. */
186: setproctitle("client (%s)", socket_path);
187: logfile("client");
188:
189: /* Create imsg. */
1.25 nicm 190: imsg_init(&client_ibuf, fd);
1.46 nicm 191: event_set(&client_event, fd, EV_READ, client_callback, shell_cmd);
192:
193: /* Establish signal handlers. */
194: set_signals(client_signal);
1.1 nicm 195:
1.46 nicm 196: /* Send initial environment. */
1.11 nicm 197: if (cmdflags & CMD_SENDENVIRON)
1.25 nicm 198: client_send_environ();
1.42 nicm 199: client_send_identify(flags);
1.1 nicm 200:
1.46 nicm 201: /* Send first command. */
202: if (msg == MSG_COMMAND) {
203: /* Fill in command line arguments. */
204: cmddata.pid = environ_pid;
205: cmddata.idx = environ_idx;
206:
207: /* Prepare command for server. */
208: cmddata.argc = argc;
209: if (cmd_pack_argv(
210: argc, argv, cmddata.argv, sizeof cmddata.argv) != 0) {
211: log_warnx("command too long");
212: return (1);
213: }
214:
215: client_write_server(msg, &cmddata, sizeof cmddata);
216: } else if (msg == MSG_SHELL)
217: client_write_server(msg, NULL, 0);
1.1 nicm 218:
1.46 nicm 219: /* Set the event and dispatch. */
220: client_update_event();
221: event_dispatch();
222:
223: /* Print the exit message, if any, and exit. */
1.48 nicm 224: if (client_attached) {
225: if (client_exitmsg != NULL && !login_shell)
226: printf("[%s]\n", client_exitmsg);
227:
228: ppid = getppid();
229: if (client_exittype == MSG_DETACHKILL && ppid > 1)
230: kill(ppid, SIGHUP);
231: }
1.46 nicm 232: return (client_exitval);
1.1 nicm 233: }
234:
1.46 nicm 235: /* Send identify message to server with the file descriptors. */
1.11 nicm 236: void
1.26 nicm 237: client_send_identify(int flags)
238: {
239: struct msg_identify_data data;
240: char *term;
241: int fd;
242:
243: data.flags = flags;
244:
245: if (getcwd(data.cwd, sizeof data.cwd) == NULL)
246: *data.cwd = '\0';
1.35 nicm 247:
1.26 nicm 248: term = getenv("TERM");
249: if (term == NULL ||
250: strlcpy(data.term, term, sizeof data.term) >= sizeof data.term)
251: *data.term = '\0';
252:
253: if ((fd = dup(STDIN_FILENO)) == -1)
254: fatal("dup failed");
255: imsg_compose(&client_ibuf,
256: MSG_IDENTIFY, PROTOCOL_VERSION, -1, fd, &data, sizeof data);
1.42 nicm 257:
258: if ((fd = dup(STDOUT_FILENO)) == -1)
259: fatal("dup failed");
1.46 nicm 260: imsg_compose(&client_ibuf,
261: MSG_STDOUT, PROTOCOL_VERSION, -1, fd, NULL, 0);
1.42 nicm 262:
263: if ((fd = dup(STDERR_FILENO)) == -1)
264: fatal("dup failed");
1.46 nicm 265: imsg_compose(&client_ibuf,
266: MSG_STDERR, PROTOCOL_VERSION, -1, fd, NULL, 0);
1.26 nicm 267: }
268:
1.46 nicm 269: /* Forward entire environment to server. */
1.26 nicm 270: void
1.25 nicm 271: client_send_environ(void)
1.11 nicm 272: {
1.26 nicm 273: struct msg_environ_data data;
1.11 nicm 274: char **var;
275:
1.35 nicm 276: for (var = environ; *var != NULL; var++) {
1.11 nicm 277: if (strlcpy(data.var, *var, sizeof data.var) >= sizeof data.var)
278: continue;
1.25 nicm 279: client_write_server(MSG_ENVIRON, &data, sizeof data);
1.11 nicm 280: }
281: }
282:
1.46 nicm 283: /* Write a message to the server without a file descriptor. */
1.25 nicm 284: void
285: client_write_server(enum msgtype type, void *buf, size_t len)
286: {
1.35 nicm 287: imsg_compose(&client_ibuf, type, PROTOCOL_VERSION, -1, -1, buf, len);
1.25 nicm 288: }
289:
1.46 nicm 290: /* Update client event based on whether it needs to read or read and write. */
1.31 nicm 291: void
292: client_update_event(void)
293: {
294: short events;
295:
296: event_del(&client_event);
297: events = EV_READ;
298: if (client_ibuf.w.queued > 0)
299: events |= EV_WRITE;
1.46 nicm 300: event_set(
301: &client_event, client_ibuf.fd, events, client_callback, shell_cmd);
1.31 nicm 302: event_add(&client_event, NULL);
303: }
304:
1.46 nicm 305: /* Callback to handle signals in the client. */
1.34 nicm 306: /* ARGSUSED */
1.30 nicm 307: void
1.31 nicm 308: client_signal(int sig, unused short events, unused void *data)
1.30 nicm 309: {
1.46 nicm 310: struct sigaction sigact;
311: int status;
1.30 nicm 312:
1.46 nicm 313: if (!client_attached) {
314: switch (sig) {
315: case SIGCHLD:
316: waitpid(WAIT_ANY, &status, WNOHANG);
317: break;
318: case SIGTERM:
319: event_loopexit(NULL);
320: break;
321: }
322: } else {
323: switch (sig) {
324: case SIGHUP:
325: client_exitmsg = "lost tty";
326: client_exitval = 1;
327: client_write_server(MSG_EXITING, NULL, 0);
328: break;
329: case SIGTERM:
330: client_exitmsg = "terminated";
331: client_exitval = 1;
332: client_write_server(MSG_EXITING, NULL, 0);
333: break;
334: case SIGWINCH:
335: client_write_server(MSG_RESIZE, NULL, 0);
336: break;
337: case SIGCONT:
338: memset(&sigact, 0, sizeof sigact);
339: sigemptyset(&sigact.sa_mask);
340: sigact.sa_flags = SA_RESTART;
341: sigact.sa_handler = SIG_IGN;
342: if (sigaction(SIGTSTP, &sigact, NULL) != 0)
343: fatal("sigaction failed");
344: client_write_server(MSG_WAKEUP, NULL, 0);
345: break;
346: }
1.30 nicm 347: }
348:
1.31 nicm 349: client_update_event();
1.30 nicm 350: }
351:
1.46 nicm 352: /* Callback for client imsg read events. */
1.34 nicm 353: /* ARGSUSED */
1.30 nicm 354: void
1.46 nicm 355: client_callback(unused int fd, short events, void *data)
1.30 nicm 356: {
1.33 nicm 357: ssize_t n;
1.46 nicm 358: int retval;
1.30 nicm 359:
360: if (events & EV_READ) {
361: if ((n = imsg_read(&client_ibuf)) == -1 || n == 0)
362: goto lost_server;
1.46 nicm 363: if (client_attached)
364: retval = client_dispatch_attached();
365: else
366: retval = client_dispatch_wait(data);
367: if (retval != 0) {
1.30 nicm 368: event_loopexit(NULL);
369: return;
1.35 nicm 370: }
1.30 nicm 371: }
1.35 nicm 372:
1.30 nicm 373: if (events & EV_WRITE) {
374: if (msgbuf_write(&client_ibuf.w) < 0)
375: goto lost_server;
376: }
377:
1.31 nicm 378: client_update_event();
1.30 nicm 379: return;
380:
381: lost_server:
382: client_exitmsg = "lost server";
1.32 nicm 383: client_exitval = 1;
1.30 nicm 384: event_loopexit(NULL);
385: }
386:
1.46 nicm 387: /* Dispatch imsgs when in wait state (before MSG_READY). */
388: int
389: client_dispatch_wait(void *data)
390: {
391: struct imsg imsg;
392: ssize_t n, datalen;
393: struct msg_shell_data shelldata;
394: struct msg_exit_data exitdata;
395: const char *shellcmd = data;
396:
397: if ((n = imsg_read(&client_ibuf)) == -1 || n == 0)
398: fatalx("imsg_read failed");
399:
400: for (;;) {
401: if ((n = imsg_get(&client_ibuf, &imsg)) == -1)
402: fatalx("imsg_get failed");
403: if (n == 0)
404: return (0);
405: datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
406:
407: switch (imsg.hdr.type) {
408: case MSG_EXIT:
409: case MSG_SHUTDOWN:
410: if (datalen != sizeof exitdata) {
411: if (datalen != 0)
412: fatalx("bad MSG_EXIT size");
413: } else {
414: memcpy(&exitdata, imsg.data, sizeof exitdata);
415: client_exitval = exitdata.retcode;
416: }
417: imsg_free(&imsg);
418: return (-1);
419: case MSG_READY:
420: if (datalen != 0)
421: fatalx("bad MSG_READY size");
422:
423: client_attached = 1;
424: break;
425: case MSG_VERSION:
426: if (datalen != 0)
427: fatalx("bad MSG_VERSION size");
428:
429: log_warnx("protocol version mismatch (client %u, "
430: "server %u)", PROTOCOL_VERSION, imsg.hdr.peerid);
431: client_exitval = 1;
432:
433: imsg_free(&imsg);
434: return (-1);
435: case MSG_SHELL:
436: if (datalen != sizeof shelldata)
437: fatalx("bad MSG_SHELL size");
438: memcpy(&shelldata, imsg.data, sizeof shelldata);
439: shelldata.shell[(sizeof shelldata.shell) - 1] = '\0';
440:
441: clear_signals(0);
442:
443: shell_exec(shelldata.shell, shellcmd);
444: /* NOTREACHED */
445: default:
446: fatalx("unexpected message");
447: }
448:
449: imsg_free(&imsg);
450: }
451: }
452:
453: /* Dispatch imsgs in attached state (after MSG_READY). */
454: /* ARGSUSED */
1.9 nicm 455: int
1.46 nicm 456: client_dispatch_attached(void)
1.9 nicm 457: {
1.30 nicm 458: struct imsg imsg;
459: struct msg_lock_data lockdata;
460: struct sigaction sigact;
461: ssize_t n, datalen;
1.9 nicm 462:
463: for (;;) {
1.25 nicm 464: if ((n = imsg_get(&client_ibuf, &imsg)) == -1)
1.12 nicm 465: fatalx("imsg_get failed");
466: if (n == 0)
1.9 nicm 467: return (0);
1.12 nicm 468: datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1.9 nicm 469:
1.30 nicm 470: log_debug("client got %d", imsg.hdr.type);
1.12 nicm 471: switch (imsg.hdr.type) {
1.48 nicm 472: case MSG_DETACHKILL:
1.9 nicm 473: case MSG_DETACH:
1.12 nicm 474: if (datalen != 0)
1.9 nicm 475: fatalx("bad MSG_DETACH size");
476:
1.48 nicm 477: client_exittype = imsg.hdr.type;
478: if (imsg.hdr.type == MSG_DETACHKILL)
479: client_exitmsg = "detached and SIGHUP";
480: else
481: client_exitmsg = "detached";
1.25 nicm 482: client_write_server(MSG_EXITING, NULL, 0);
1.9 nicm 483: break;
484: case MSG_EXIT:
1.43 nicm 485: if (datalen != 0 &&
486: datalen != sizeof (struct msg_exit_data))
1.9 nicm 487: fatalx("bad MSG_EXIT size");
1.12 nicm 488:
1.25 nicm 489: client_write_server(MSG_EXITING, NULL, 0);
490: client_exitmsg = "exited";
1.9 nicm 491: break;
492: case MSG_EXITED:
1.12 nicm 493: if (datalen != 0)
1.9 nicm 494: fatalx("bad MSG_EXITED size");
495:
1.12 nicm 496: imsg_free(&imsg);
1.9 nicm 497: return (-1);
498: case MSG_SHUTDOWN:
1.12 nicm 499: if (datalen != 0)
1.9 nicm 500: fatalx("bad MSG_SHUTDOWN size");
501:
1.25 nicm 502: client_write_server(MSG_EXITING, NULL, 0);
503: client_exitmsg = "server exited";
1.32 nicm 504: client_exitval = 1;
1.9 nicm 505: break;
506: case MSG_SUSPEND:
1.12 nicm 507: if (datalen != 0)
1.9 nicm 508: fatalx("bad MSG_SUSPEND size");
509:
1.30 nicm 510: memset(&sigact, 0, sizeof sigact);
511: sigemptyset(&sigact.sa_mask);
512: sigact.sa_flags = SA_RESTART;
513: sigact.sa_handler = SIG_DFL;
514: if (sigaction(SIGTSTP, &sigact, NULL) != 0)
515: fatal("sigaction failed");
516: kill(getpid(), SIGTSTP);
1.21 nicm 517: break;
518: case MSG_LOCK:
519: if (datalen != sizeof lockdata)
520: fatalx("bad MSG_LOCK size");
521: memcpy(&lockdata, imsg.data, sizeof lockdata);
1.35 nicm 522:
1.21 nicm 523: lockdata.cmd[(sizeof lockdata.cmd) - 1] = '\0';
524: system(lockdata.cmd);
1.25 nicm 525: client_write_server(MSG_UNLOCK, NULL, 0);
1.9 nicm 526: break;
527: default:
528: fatalx("unexpected message");
529: }
1.12 nicm 530:
531: imsg_free(&imsg);
1.9 nicm 532: }
1.1 nicm 533: }
![[BACK]](/icons/back.gif){kind=icon}
Return to client.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / tmux