remount: add tool that applies /etc/fstab mount options to all api mounts

1 files changed, 147 insertions, 0 deletions

diff --git a/src/remount-api-vfs.c b/src/remount-api-vfs.c
new file mode 100644
index 0000000000..d51a584f2f
--- /dev/null
+++ b/src/remount-api-vfs.c
@@ -0,0 +1,147 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2010 Lennart Poettering
+
+  systemd 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.
+
+  systemd 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 systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <mntent.h>
+
+#include "log.h"
+#include "util.h"
+#include "set.h"
+#include "mount-setup.h"
+
+/* Goes through /etc/fstab and remounts all API file systems, applying
+ * options that are in /etc/fstab that systemd might not have
+ * respected */
+
+int main(int argc, char *argv[]) {
+        int ret = 1;
+        FILE *f = NULL;
+        struct mntent* me;
+        Hashmap *pids = NULL;
+
+        if (argc > 1) {
+                log_error("This program takes no argument.");
+                return 1;
+        }
+
+        log_set_target(LOG_TARGET_SYSLOG_OR_KMSG);
+        log_parse_environment();
+        log_open();
+
+        if (!(f = setmntent("/etc/fstab", "r"))) {
+                log_error("Failed to open /etc/fstab: %m");
+                goto finish;
+        }
+
+        if (!(pids = hashmap_new(trivial_hash_func, trivial_compare_func))) {
+                log_error("Failed to allocate set");
+                goto finish;
+        }
+
+        ret = 0;
+
+        while ((me = getmntent(f))) {
+                pid_t pid;
+                int k;
+                char *s;
+
+                if (!mount_point_is_api(me->mnt_dir))
+                        continue;
+
+                log_debug("Remounting %s", me->mnt_dir);
+
+                if ((pid = fork()) < 0) {
+                        log_error("Failed to fork: %m");
+                        ret = 1;
+                        continue;
+                }
+
+                if (pid == 0) {
+                        const char *arguments[5];
+                        /* Child */
+
+                        arguments[0] = "/bin/mount";
+                        arguments[1] = me->mnt_dir;
+                        arguments[2] = "-o";
+                        arguments[3] = "remount";
+                        arguments[4] = NULL;
+
+                        execv("/bin/mount", (char **) arguments);
+
+                        log_error("Failed to execute /bin/mount: %m");
+                        _exit(1);
+                }
+
+                /* Parent */
+
+                s = strdup(me->mnt_dir);
+
+                if ((k = hashmap_put(pids, UINT_TO_PTR(pid), s)) < 0) {
+                        log_error("Failed to add PID to set: %s", strerror(-k));
+                        ret = 1;
+                        continue;
+                }
+        }
+
+        while (!hashmap_isempty(pids)) {
+                siginfo_t si;
+                char *s;
+
+                zero(si);
+                if (waitid(P_ALL, 0, &si, WEXITED) < 0) {
+
+                        if (errno == EINTR)
+                                continue;
+
+                        log_error("waitid() failed: %m");
+                        ret = 1;
+                        break;
+                }
+
+                if ((s = hashmap_remove(pids, UINT_TO_PTR(si.si_pid)))) {
+                        if (!is_clean_exit(si.si_code, si.si_status)) {
+                                if (si.si_code == CLD_EXITED)
+                                        log_error("/bin/mount for %s exited with exit status %i.", s, si.si_status);
+                                else
+                                        log_error("/bin/mount for %s terminated by signal %s.", s, signal_to_string(si.si_status));
+
+                                ret = 1;
+                        }
+
+                        free(s);
+                }
+        }
+
+finish:
+
+        if (pids)
+                hashmap_free_free(pids);
+
+        if (f)
+                endmntent(f);
+
+        return ret;
+}