1 /* $OpenBSD: job.c,v 1.52 2018/09/27 07:43:18 nicm Exp $ */ 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 <fcntl.h> 23 #include <paths.h> 24 #include <signal.h> 25 #include <stdlib.h> 26 #include <string.h> 27 #include <unistd.h> 28 29 #include "tmux.h" 30 31 /* 32 * Job scheduling. Run queued commands in the background and record their 33 * output. 34 */ 35 36 static void job_read_callback(struct bufferevent *, void *); 37 static void job_write_callback(struct bufferevent *, void *); 38 static void job_error_callback(struct bufferevent *, short, void *); 39 40 /* A single job. */ 41 struct job { 42 enum { 43 JOB_RUNNING, 44 JOB_DEAD, 45 JOB_CLOSED 46 } state; 47 48 int flags; 49 50 char *cmd; 51 pid_t pid; 52 int status; 53 54 int fd; 55 struct bufferevent *event; 56 57 job_update_cb updatecb; 58 job_complete_cb completecb; 59 job_free_cb freecb; 60 void *data; 61 62 LIST_ENTRY(job) entry; 63 }; 64 65 /* All jobs list. */ 66 static LIST_HEAD(joblist, job) all_jobs = LIST_HEAD_INITIALIZER(all_jobs); 67 68 /* Start a job running, if it isn't already. */ 69 struct job * 70 job_run(const char *cmd, struct session *s, const char *cwd, 71 job_update_cb updatecb, job_complete_cb completecb, job_free_cb freecb, 72 void *data, int flags) 73 { 74 struct job *job; 75 struct environ *env; 76 pid_t pid; 77 int nullfd, out[2]; 78 const char *home; 79 sigset_t set, oldset; 80 81 if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, out) != 0) 82 return (NULL); 83 log_debug("%s: cmd=%s, cwd=%s", __func__, cmd, cwd); 84 85 /* 86 * Do not set TERM during .tmux.conf, it is nice to be able to use 87 * if-shell to decide on default-terminal based on outside TERM. 88 */ 89 env = environ_for_session(s, !cfg_finished); 90 91 sigfillset(&set); 92 sigprocmask(SIG_BLOCK, &set, &oldset); 93 switch (pid = fork()) { 94 case -1: 95 sigprocmask(SIG_SETMASK, &oldset, NULL); 96 environ_free(env); 97 close(out[0]); 98 close(out[1]); 99 return (NULL); 100 case 0: 101 proc_clear_signals(server_proc, 1); 102 sigprocmask(SIG_SETMASK, &oldset, NULL); 103 104 if (cwd == NULL || chdir(cwd) != 0) { 105 if ((home = find_home()) == NULL || chdir(home) != 0) 106 chdir("/"); 107 } 108 109 environ_push(env); 110 environ_free(env); 111 112 if (dup2(out[1], STDIN_FILENO) == -1) 113 fatal("dup2 failed"); 114 if (dup2(out[1], STDOUT_FILENO) == -1) 115 fatal("dup2 failed"); 116 if (out[1] != STDIN_FILENO && out[1] != STDOUT_FILENO) 117 close(out[1]); 118 close(out[0]); 119 120 nullfd = open(_PATH_DEVNULL, O_RDWR, 0); 121 if (nullfd < 0) 122 fatal("open failed"); 123 if (dup2(nullfd, STDERR_FILENO) == -1) 124 fatal("dup2 failed"); 125 if (nullfd != STDERR_FILENO) 126 close(nullfd); 127 128 closefrom(STDERR_FILENO + 1); 129 130 execl(_PATH_BSHELL, "sh", "-c", cmd, (char *) NULL); 131 fatal("execl failed"); 132 } 133 134 sigprocmask(SIG_SETMASK, &oldset, NULL); 135 environ_free(env); 136 close(out[1]); 137 138 job = xmalloc(sizeof *job); 139 job->state = JOB_RUNNING; 140 job->flags = flags; 141 142 job->cmd = xstrdup(cmd); 143 job->pid = pid; 144 job->status = 0; 145 146 LIST_INSERT_HEAD(&all_jobs, job, entry); 147 148 job->updatecb = updatecb; 149 job->completecb = completecb; 150 job->freecb = freecb; 151 job->data = data; 152 153 job->fd = out[0]; 154 setblocking(job->fd, 0); 155 156 job->event = bufferevent_new(job->fd, job_read_callback, 157 job_write_callback, job_error_callback, job); 158 bufferevent_enable(job->event, EV_READ|EV_WRITE); 159 160 log_debug("run job %p: %s, pid %ld", job, job->cmd, (long) job->pid); 161 return (job); 162 } 163 164 /* Kill and free an individual job. */ 165 void 166 job_free(struct job *job) 167 { 168 log_debug("free job %p: %s", job, job->cmd); 169 170 LIST_REMOVE(job, entry); 171 free(job->cmd); 172 173 if (job->freecb != NULL && job->data != NULL) 174 job->freecb(job->data); 175 176 if (job->pid != -1) 177 kill(job->pid, SIGTERM); 178 if (job->event != NULL) 179 bufferevent_free(job->event); 180 if (job->fd != -1) 181 close(job->fd); 182 183 free(job); 184 } 185 186 /* Job buffer read callback. */ 187 static void 188 job_read_callback(__unused struct bufferevent *bufev, void *data) 189 { 190 struct job *job = data; 191 192 if (job->updatecb != NULL) 193 job->updatecb(job); 194 } 195 196 /* 197 * Job buffer write callback. Fired when the buffer falls below watermark 198 * (default is empty). If all the data has been written, disable the write 199 * event. 200 */ 201 static void 202 job_write_callback(__unused struct bufferevent *bufev, void *data) 203 { 204 struct job *job = data; 205 size_t len = EVBUFFER_LENGTH(EVBUFFER_OUTPUT(job->event)); 206 207 log_debug("job write %p: %s, pid %ld, output left %zu", job, job->cmd, 208 (long) job->pid, len); 209 210 if (len == 0) { 211 shutdown(job->fd, SHUT_WR); 212 bufferevent_disable(job->event, EV_WRITE); 213 } 214 } 215 216 /* Job buffer error callback. */ 217 static void 218 job_error_callback(__unused struct bufferevent *bufev, __unused short events, 219 void *data) 220 { 221 struct job *job = data; 222 223 log_debug("job error %p: %s, pid %ld", job, job->cmd, (long) job->pid); 224 225 if (job->state == JOB_DEAD) { 226 if (job->completecb != NULL) 227 job->completecb(job); 228 job_free(job); 229 } else { 230 bufferevent_disable(job->event, EV_READ); 231 job->state = JOB_CLOSED; 232 } 233 } 234 235 /* Job died (waitpid() returned its pid). */ 236 void 237 job_check_died(pid_t pid, int status) 238 { 239 struct job *job; 240 241 LIST_FOREACH(job, &all_jobs, entry) { 242 if (pid == job->pid) 243 break; 244 } 245 if (job == NULL) 246 return; 247 log_debug("job died %p: %s, pid %ld", job, job->cmd, (long) job->pid); 248 249 job->status = status; 250 251 if (job->state == JOB_CLOSED) { 252 if (job->completecb != NULL) 253 job->completecb(job); 254 job_free(job); 255 } else { 256 job->pid = -1; 257 job->state = JOB_DEAD; 258 } 259 } 260 261 /* Get job status. */ 262 int 263 job_get_status(struct job *job) 264 { 265 return (job->status); 266 } 267 268 /* Get job data. */ 269 void * 270 job_get_data(struct job *job) 271 { 272 return (job->data); 273 } 274 275 /* Get job event. */ 276 struct bufferevent * 277 job_get_event(struct job *job) 278 { 279 return (job->event); 280 } 281 282 /* Kill all jobs. */ 283 void 284 job_kill_all(void) 285 { 286 struct job *job; 287 288 LIST_FOREACH(job, &all_jobs, entry) { 289 if (job->pid != -1) 290 kill(job->pid, SIGTERM); 291 } 292 } 293 294 /* Are any jobs still running? */ 295 int 296 job_still_running(void) 297 { 298 struct job *job; 299 300 LIST_FOREACH(job, &all_jobs, entry) { 301 if ((~job->flags & JOB_NOWAIT) && job->state == JOB_RUNNING) 302 return (1); 303 } 304 return (0); 305 } 306 307 /* Print job summary. */ 308 void 309 job_print_summary(struct cmdq_item *item, int blank) 310 { 311 struct job *job; 312 u_int n = 0; 313 314 LIST_FOREACH(job, &all_jobs, entry) { 315 if (blank) { 316 cmdq_print(item, "%s", ""); 317 blank = 0; 318 } 319 cmdq_print(item, "Job %u: %s [fd=%d, pid=%ld, status=%d]", 320 n, job->cmd, job->fd, (long)job->pid, job->status); 321 n++; 322 } 323 } 324