1 /* $Id: job.c,v 1.2 2011/03/12 03:02:59 christos 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 <fcntl.h> 23 #include <string.h> 24 #include <unistd.h> 25 26 #include "tmux.h" 27 28 /* 29 * Job scheduling. Run queued commands in the background and record their 30 * output. 31 */ 32 33 /* All jobs list. */ 34 struct joblist all_jobs = SLIST_HEAD_INITIALIZER(all_jobs); 35 36 RB_GENERATE(jobs, job, entry, job_cmp); 37 38 void job_callback(struct bufferevent *, short, void *); 39 40 int 41 job_cmp(struct job *job1, struct job *job2) 42 { 43 return (strcmp(job1->cmd, job2->cmd)); 44 } 45 46 /* Initialise job tree. */ 47 void 48 job_tree_init(struct jobs *jobs) 49 { 50 RB_INIT(jobs); 51 } 52 53 /* Destroy a job tree. */ 54 void 55 job_tree_free(struct jobs *jobs) 56 { 57 struct job *job; 58 59 while (!RB_EMPTY(jobs)) { 60 job = RB_ROOT(jobs); 61 RB_REMOVE(jobs, jobs, job); 62 job_free(job); 63 } 64 } 65 66 /* Find a job and return it. */ 67 struct job * 68 job_get(struct jobs *jobs, const char *cmd) 69 { 70 struct job job; 71 72 job.cmd = __UNCONST(cmd); 73 return (RB_FIND(jobs, jobs, &job)); 74 } 75 76 /* Add a job. */ 77 struct job * 78 job_add(struct jobs *jobs, int flags, struct client *c, const char *cmd, 79 void (*callbackfn)(struct job *), void (*freefn)(void *), void *data) 80 { 81 struct job *job; 82 83 job = xmalloc(sizeof *job); 84 job->cmd = xstrdup(cmd); 85 job->pid = -1; 86 job->status = 0; 87 88 job->client = c; 89 90 job->fd = -1; 91 job->event = NULL; 92 93 job->callbackfn = callbackfn; 94 job->freefn = freefn; 95 job->data = data; 96 97 job->flags = flags; 98 99 if (jobs != NULL) 100 RB_INSERT(jobs, jobs, job); 101 SLIST_INSERT_HEAD(&all_jobs, job, lentry); 102 103 return (job); 104 } 105 106 /* Remove job from tree and free. */ 107 void 108 job_remove(struct jobs *jobs, struct job *job) 109 { 110 if (jobs != NULL) 111 RB_REMOVE(jobs, jobs, job); 112 job_free(job); 113 } 114 115 /* Kill and free an individual job. */ 116 void 117 job_free(struct job *job) 118 { 119 job_kill(job); 120 121 SLIST_REMOVE(&all_jobs, job, job, lentry); 122 xfree(job->cmd); 123 124 if (job->freefn != NULL && job->data != NULL) 125 job->freefn(job->data); 126 127 if (job->fd != -1) 128 close(job->fd); 129 if (job->event != NULL) 130 bufferevent_free(job->event); 131 132 xfree(job); 133 } 134 135 /* Start a job running, if it isn't already. */ 136 int 137 job_run(struct job *job) 138 { 139 int nullfd, out[2], mode; 140 141 if (job->fd != -1 || job->pid != -1) 142 return (0); 143 144 if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, out) != 0) 145 return (-1); 146 147 switch (job->pid = fork()) { 148 case -1: 149 return (-1); 150 case 0: /* child */ 151 clear_signals(1); 152 153 environ_push(&global_environ); 154 155 if (dup2(out[1], STDOUT_FILENO) == -1) 156 fatal("dup2 failed"); 157 if (out[1] != STDOUT_FILENO) 158 close(out[1]); 159 close(out[0]); 160 161 nullfd = open(_PATH_DEVNULL, O_RDWR, 0); 162 if (nullfd < 0) 163 fatal("open failed"); 164 if (dup2(nullfd, STDIN_FILENO) == -1) 165 fatal("dup2 failed"); 166 if (dup2(nullfd, STDERR_FILENO) == -1) 167 fatal("dup2 failed"); 168 if (nullfd != STDIN_FILENO && nullfd != STDERR_FILENO) 169 close(nullfd); 170 171 closefrom(STDERR_FILENO + 1); 172 173 execl(_PATH_BSHELL, "sh", "-c", job->cmd, (char *) NULL); 174 fatal("execl failed"); 175 default: /* parent */ 176 close(out[1]); 177 178 job->fd = out[0]; 179 if ((mode = fcntl(job->fd, F_GETFL)) == -1) 180 fatal("fcntl failed"); 181 if (fcntl(job->fd, F_SETFL, mode|O_NONBLOCK) == -1) 182 fatal("fcntl failed"); 183 184 if (job->event != NULL) 185 bufferevent_free(job->event); 186 job->event = 187 bufferevent_new(job->fd, NULL, NULL, job_callback, job); 188 bufferevent_enable(job->event, EV_READ); 189 190 return (0); 191 } 192 } 193 194 /* Job buffer error callback. */ 195 /* ARGSUSED */ 196 void 197 job_callback(unused struct bufferevent *bufev, unused short events, void *data) 198 { 199 struct job *job = data; 200 201 bufferevent_disable(job->event, EV_READ); 202 close(job->fd); 203 job->fd = -1; 204 205 if (job->pid == -1) { 206 if (job->callbackfn != NULL) 207 job->callbackfn(job); 208 if ((!job->flags & JOB_PERSIST)) 209 job_free(job); 210 } 211 } 212 213 /* Job died (waitpid() returned its pid). */ 214 void 215 job_died(struct job *job, int status) 216 { 217 job->status = status; 218 job->pid = -1; 219 220 if (job->fd == -1) { 221 if (job->callbackfn != NULL) 222 job->callbackfn(job); 223 if ((!job->flags & JOB_PERSIST)) 224 job_free(job); 225 } 226 } 227 228 /* Kill a job. */ 229 void 230 job_kill(struct job *job) 231 { 232 if (job->pid == -1) 233 return; 234 kill(job->pid, SIGTERM); 235 job->pid = -1; 236 } 237