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Diffstat (limited to 'usr.sbin/autofs/popen.c')
| -rw-r--r-- | usr.sbin/autofs/popen.c | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/usr.sbin/autofs/popen.c b/usr.sbin/autofs/popen.c new file mode 100644 index 0000000..e114880 --- /dev/null +++ b/usr.sbin/autofs/popen.c @@ -0,0 +1,193 @@ +/* + * Copyright (c) 1988, 1993 + * The Regents of the University of California. All rights reserved. + * Copyright (c) 2014 The FreeBSD Foundation + * All rights reserved. + * + * This code is derived from software written by Ken Arnold and + * published in UNIX Review, Vol. 6, No. 8. + * + * Portions of this software were developed by Edward Tomasz Napierala + * under sponsorship from the FreeBSD Foundation. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/param.h> +#include <sys/queue.h> +#include <sys/wait.h> + +#include <errno.h> +#include <fcntl.h> +#include <unistd.h> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <paths.h> + +#include "common.h" + +extern char **environ; + +struct pid { + SLIST_ENTRY(pid) next; + FILE *outfp; + pid_t pid; + char *command; +}; +static SLIST_HEAD(, pid) pidlist = SLIST_HEAD_INITIALIZER(pidlist); + +#define ARGV_LEN 42 + +/* + * Replacement for popen(3), without stdin (which we do not use), but with + * stderr, proper logging, and improved command line arguments passing. + * Error handling is built in - if it returns, then it succeeded. + */ +FILE * +auto_popen(const char *argv0, ...) +{ + va_list ap; + struct pid *cur, *p; + pid_t pid; + int error, i, nullfd, outfds[2]; + char *arg, *argv[ARGV_LEN], *command; + + nullfd = open(_PATH_DEVNULL, O_RDWR, 0); + if (nullfd < 0) + log_err(1, "cannot open %s", _PATH_DEVNULL); + + error = pipe(outfds); + if (error != 0) + log_err(1, "pipe"); + + cur = malloc(sizeof(struct pid)); + if (cur == NULL) + log_err(1, "malloc"); + + argv[0] = checked_strdup(argv0); + command = argv[0]; + + va_start(ap, argv0); + for (i = 1;; i++) { + if (i >= ARGV_LEN) + log_errx(1, "too many arguments to auto_popen"); + arg = va_arg(ap, char *); + argv[i] = arg; + if (arg == NULL) + break; + + command = concat(command, ' ', arg); + } + va_end(ap); + + cur->command = checked_strdup(command); + + switch (pid = fork()) { + case -1: /* Error. */ + log_err(1, "fork"); + /* NOTREACHED */ + case 0: /* Child. */ + dup2(nullfd, STDIN_FILENO); + dup2(outfds[1], STDOUT_FILENO); + + close(nullfd); + close(outfds[0]); + close(outfds[1]); + + SLIST_FOREACH(p, &pidlist, next) + close(fileno(p->outfp)); + execvp(argv[0], argv); + log_err(1, "failed to execute %s", argv[0]); + /* NOTREACHED */ + } + + log_debugx("executing \"%s\" as pid %d", command, pid); + + /* Parent; assume fdopen cannot fail. */ + cur->outfp = fdopen(outfds[0], "r"); + close(nullfd); + close(outfds[1]); + + /* Link into list of file descriptors. */ + cur->pid = pid; + SLIST_INSERT_HEAD(&pidlist, cur, next); + + return (cur->outfp); +} + +int +auto_pclose(FILE *iop) +{ + struct pid *cur, *last = NULL; + int status; + pid_t pid; + + /* + * Find the appropriate file pointer and remove it from the list. + */ + SLIST_FOREACH(cur, &pidlist, next) { + if (cur->outfp == iop) + break; + last = cur; + } + if (cur == NULL) { + return (-1); + } + if (last == NULL) + SLIST_REMOVE_HEAD(&pidlist, next); + else + SLIST_REMOVE_AFTER(last, next); + + fclose(cur->outfp); + + do { + pid = wait4(cur->pid, &status, 0, NULL); + } while (pid == -1 && errno == EINTR); + + if (WIFSIGNALED(status)) { + log_warnx("\"%s\", pid %d, terminated with signal %d", + cur->command, pid, WTERMSIG(status)); + return (status); + } + + if (WEXITSTATUS(status) != 0) { + log_warnx("\"%s\", pid %d, terminated with exit status %d", + cur->command, pid, WEXITSTATUS(status)); + return (status); + } + + log_debugx("\"%s\", pid %d, terminated gracefully", cur->command, pid); + + free(cur->command); + free(cur); + + return (pid == -1 ? -1 : status); +} |
