diff options
Diffstat (limited to 'lib/dpkg/subproc.c')
| -rw-r--r-- | lib/dpkg/subproc.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/lib/dpkg/subproc.c b/lib/dpkg/subproc.c new file mode 100644 index 0000000..7b3fb99 --- /dev/null +++ b/lib/dpkg/subproc.c @@ -0,0 +1,195 @@ +/* + * libdpkg - Debian packaging suite library routines + * subproc.c - subprocess helper routines + * + * Copyright © 1995 Ian Jackson <ijackson@chiark.greenend.org.uk> + * Copyright © 2008-2014 Guillem Jover <guillem@debian.org> + * + * This is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <https://www.gnu.org/licenses/>. + */ + +#include <config.h> +#include <compat.h> + +#include <sys/types.h> +#include <sys/wait.h> + +#include <errno.h> +#include <string.h> +#include <signal.h> +#include <unistd.h> +#include <stdlib.h> +#include <stdio.h> + +#include <dpkg/i18n.h> +#include <dpkg/dpkg.h> +#include <dpkg/subproc.h> + +static int signo_ignores[] = { SIGQUIT, SIGINT }; +static struct sigaction sa_save[array_count(signo_ignores)]; + +static void +subproc_reset_signal(int sig, struct sigaction *sa_old) +{ + if (sigaction(sig, sa_old, NULL)) { + fprintf(stderr, _("error un-catching signal %s: %s\n"), + strsignal(sig), strerror(errno)); + onerr_abort++; + } +} + +static void +subproc_set_signal(int sig, struct sigaction *sa, struct sigaction *sa_old, + const char *name) +{ + if (sigaction(sig, sa, sa_old)) + ohshite(_("unable to ignore signal %s before running %.250s"), + strsignal(sig), name); +} + +void +subproc_signals_ignore(const char *name) +{ + struct sigaction sa; + size_t i; + + onerr_abort++; + memset(&sa, 0, sizeof(sa)); + sigemptyset(&sa.sa_mask); + sa.sa_handler = SIG_IGN; + sa.sa_flags = 0; + + for (i = 0; i < array_count(signo_ignores); i++) + subproc_set_signal(signo_ignores[i], &sa, &sa_save[i], name); + + push_cleanup(subproc_signals_cleanup, ~0, 0); + onerr_abort--; +} + +void +subproc_signals_cleanup(int argc, void **argv) +{ + size_t i; + + for (i = 0; i < array_count(signo_ignores); i++) + subproc_reset_signal(signo_ignores[i], &sa_save[i]); +} + +void +subproc_signals_restore(void) +{ + pop_cleanup(ehflag_normaltidy); +} + +static void +print_subproc_error(const char *emsg, const void *data) +{ + fprintf(stderr, _("%s (subprocess): %s\n"), dpkg_get_progname(), emsg); +} + +pid_t +subproc_fork(void) +{ + pid_t pid; + + pid = fork(); + if (pid == -1) { + onerr_abort++; + ohshite(_("fork failed")); + } + if (pid > 0) + return pid; + + /* Push a new error context, so that we don't do the other cleanups, + * because they'll be done by/in the parent process. */ + push_error_context_func(catch_fatal_error, print_subproc_error, NULL); + + return pid; +} + +static int +subproc_check(int status, const char *desc, enum subproc_flags flags) +{ + void (*out)(const char *fmt, ...) DPKG_ATTR_PRINTF(1); + int n; + + if (flags & SUBPROC_WARN) + out = warning; + else + out = ohshit; + + if (WIFEXITED(status)) { + n = WEXITSTATUS(status); + if (!n) + return 0; + if (flags & SUBPROC_RETERROR) + return n; + + out(_("%s subprocess returned error exit status %d"), desc, n); + } else if (WIFSIGNALED(status)) { + n = WTERMSIG(status); + if (!n) + return 0; + if ((flags & SUBPROC_NOPIPE) && n == SIGPIPE) + return 0; + if (flags & SUBPROC_RETSIGNO) + return n; + + if (n == SIGINT) + out(_("%s subprocess was interrupted"), desc); + else + out(_("%s subprocess was killed by signal (%s)%s"), + desc, strsignal(n), + WCOREDUMP(status) ? _(", core dumped") : ""); + } else { + if (flags & SUBPROC_RETERROR) + return -1; + + out(_("%s subprocess failed with wait status code %d"), desc, + status); + } + + return -1; +} + +static int +subproc_wait(pid_t pid, const char *desc) +{ + pid_t dead_pid; + int status; + + while ((dead_pid = waitpid(pid, &status, 0)) == -1 && errno == EINTR) ; + + if (dead_pid != pid) { + onerr_abort++; + ohshite(_("wait for %s subprocess failed"), desc); + } + + return status; +} + +int +subproc_reap(pid_t pid, const char *desc, enum subproc_flags flags) +{ + int status, rc; + + status = subproc_wait(pid, desc); + + if (flags & SUBPROC_NOCHECK) + rc = status; + else + rc = subproc_check(status, desc, flags); + + return rc; +} |