2 * bpipe.c bi-directional pipe
4 * Kern Sibbald, November MMII
10 Copyright (C) 2002-2004 Kern Sibbald and John Walker
12 This program is free software; you can redistribute it and/or
13 modify it under the terms of the GNU General Public License as
14 published by the Free Software Foundation; either version 2 of
15 the License, or (at your option) any later version.
17 This program is distributed in the hope that it will be useful,
18 but WITHOUT ANY WARRANTY; without even the implied warranty of
19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 General Public License for more details.
22 You should have received a copy of the GNU General Public
23 License along with this program; if not, write to the Free
24 Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
34 static void build_argc_argv(char *cmd, int *bargc, char *bargv[], int max_arg);
39 * Run an external program. Optionally wait a specified number
40 * of seconds. Program killed if wait exceeded. We open
41 * a bi-directional pipe so that the user can read from and
42 * write to the program.
44 BPIPE *open_bpipe(char *prog, int wait, const char *mode)
46 char *bargv[MAX_ARGV];
48 int readp[2], writep[2];
50 int mode_read, mode_write;
53 bpipe = (BPIPE *)malloc(sizeof(BPIPE));
54 memset(bpipe, 0, sizeof(BPIPE));
55 mode_read = (mode[0] == 'r');
56 mode_write = (mode[0] == 'w' || mode[1] == 'w');
57 /* Build arguments for running program. */
58 tprog = get_pool_memory(PM_FNAME);
59 pm_strcpy(&tprog, prog);
60 build_argc_argv(mp_chr(tprog), &bargc, bargv, MAX_ARGV);
62 printf("argc=%d\n", bargc);
63 for (i=0; i<bargc; i++) {
64 printf("argc=%d argv=%s:\n", i, bargv[i]);
67 free_pool_memory(tprog);
69 /* Each pipe is one way, write one end, read the other, so we need two */
70 if (mode_write && pipe(writep) == -1) {
74 if (mode_read && pipe(readp) == -1) {
82 /* Start worker process */
83 switch (bpipe->worker_pid = fork()) {
99 dup2(writep[0], 0); /* Dup our write to his stdin */
102 close(readp[0]); /* Close unused child fds */
103 dup2(readp[1], 1); /* dup our read to his stdout */
104 dup2(readp[1], 2); /* and his stderr */
106 closelog(); /* close syslog if open */
107 for (i=3; i<=32; i++) { /* close any open file descriptors */
110 execvp(bargv[0], bargv); /* call the program */
111 exit(errno); /* shouldn't get here */
113 default: /* parent */
117 close(readp[1]); /* close unused parent fds */
118 bpipe->rfd = fdopen(readp[0], "r"); /* open file descriptor */
122 bpipe->wfd = fdopen(writep[1], "w");
124 bpipe->worker_stime = time(NULL);
127 bpipe->timer_id = start_child_timer(bpipe->worker_pid, wait);
132 /* Close the write pipe only */
133 int close_wpipe(BPIPE *bpipe)
139 if (fclose(bpipe->wfd) != 0) {
148 * Close both pipes and free resources
150 * Returns: 0 on success
153 int close_bpipe(BPIPE *bpipe)
172 if (bpipe->wait == 0) {
173 wait_option = 0; /* wait indefinitely */
175 wait_option = WNOHANG; /* don't hang */
177 remaining_wait = bpipe->wait;
179 /* wait for worker child to exit */
181 Dmsg2(200, "Wait for %d opt=%d\n", bpipe->worker_pid, wait_option);
183 wpid = waitpid(bpipe->worker_pid, &chldstatus, wait_option);
184 } while (wpid == -1 && (errno == EINTR || errno == EAGAIN));
185 if (wpid == bpipe->worker_pid || wpid == -1) {
186 Dmsg3(200, "Got break wpid=%d status=%d ERR=%s\n", wpid, chldstatus,
187 wpid==-1?strerror(errno):"none");
190 Dmsg3(200, "Got wpid=%d status=%d ERR=%s\n", wpid, chldstatus,
191 wpid==-1?strerror(errno):"none");
192 if (remaining_wait > 0) {
193 bmicrosleep(1, 0); /* wait one second */
196 stat = ETIME; /* set error status */
198 break; /* don't wait any longer */
202 if (WIFEXITED(chldstatus)) { /* process exit()ed */
203 stat = WEXITSTATUS(chldstatus);
207 Dmsg1(200, "child status=%d\n", stat);
208 } else if (WIFSIGNALED(chldstatus)) { /* process died */
210 Dmsg0(200, "Signaled\n");
213 if (bpipe->timer_id) {
214 stop_child_timer(bpipe->timer_id);
217 Dmsg1(200, "returning stat = %d\n", stat);
223 * Run an external program. Optionally wait a specified number
224 * of seconds. Program killed if wait exceeded. Optionally
225 * return the output from the program (normally a single line).
227 * Contrary to my normal calling conventions, this program
229 * Returns: 0 on success
230 * non-zero on error == errno
232 int run_program(char *prog, int wait, POOLMEM *results)
238 mode = (char *)(results != NULL ? "r" : "");
239 bpipe = open_bpipe(prog, wait, mode);
244 mp_chr(results)[0] = 0;
245 fgets(mp_chr(results), sizeof_pool_memory(results), bpipe->rfd);
246 if (feof(bpipe->rfd)) {
249 stat1 = ferror(bpipe->rfd);
252 Dmsg2(100, "Run program fgets stat=%d ERR=%s\n", stat1, strerror(errno));
253 } else if (stat1 != 0) {
254 Dmsg1(100, "Run program fgets stat=%d\n", stat1);
259 stat2 = close_bpipe(bpipe);
260 stat1 = stat2 != 0 ? stat2 : stat1;
261 Dmsg1(100, "Run program returning %d\n", stat1);
267 * Build argc and argv from a string
269 static void build_argc_argv(char *cmd, int *bargc, char *bargv[], int max_argv)
276 for (i=0; i<max_argv; i++)
281 while (*p && (*p == ' ' || *p == '\t'))
283 if (*p == '\"' || *p == '\'') {
288 while (*p && argc < MAX_ARGV) {
291 while (*q && *q != quote)
295 while (*q && *q != ' ')
302 while (*p && (*p == ' ' || *p == '\t'))
304 if (*p == '\"' || *p == '\'') {