diff options
Diffstat (limited to 'src/systemd-update-done/update-done.c')
| -rw-r--r-- | src/systemd-update-done/update-done.c | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/src/systemd-update-done/update-done.c b/src/systemd-update-done/update-done.c new file mode 100644 index 0000000000..931e583785 --- /dev/null +++ b/src/systemd-update-done/update-done.c @@ -0,0 +1,115 @@ +/*** + This file is part of systemd. + + Copyright 2014 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include "fd-util.h" +#include "io-util.h" +#include "selinux-util.h" +#include "util.h" + +#define MESSAGE \ + "This file was created by systemd-update-done. Its only \n" \ + "purpose is to hold a timestamp of the time this directory\n" \ + "was updated. See systemd-update-done.service(8).\n" + +static int apply_timestamp(const char *path, struct timespec *ts) { + struct timespec twice[2] = { + *ts, + *ts + }; + struct stat st; + + assert(path); + assert(ts); + + if (stat(path, &st) >= 0) { + /* Is the timestamp file already newer than the OS? If + * so, there's nothing to do. We ignore the nanosecond + * component of the timestamp, since some file systems + * do not support any better accuracy than 1s and we + * have no way to identify the accuracy + * available. Most notably ext4 on small disks (where + * 128 byte inodes are used) does not support better + * accuracy than 1s. */ + if (st.st_mtim.tv_sec > ts->tv_sec) + return 0; + + /* It is older? Then let's update it */ + if (utimensat(AT_FDCWD, path, twice, AT_SYMLINK_NOFOLLOW) < 0) { + + if (errno == EROFS) + return log_debug("Can't update timestamp file %s, file system is read-only.", path); + + return log_error_errno(errno, "Failed to update timestamp on %s: %m", path); + } + + } else if (errno == ENOENT) { + _cleanup_close_ int fd = -1; + int r; + + /* The timestamp file doesn't exist yet? Then let's create it. */ + + r = mac_selinux_create_file_prepare(path, S_IFREG); + if (r < 0) + return log_error_errno(r, "Failed to set SELinux context for %s: %m", path); + + fd = open(path, O_CREAT|O_EXCL|O_WRONLY|O_TRUNC|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW, 0644); + mac_selinux_create_file_clear(); + + if (fd < 0) { + if (errno == EROFS) + return log_debug("Can't create timestamp file %s, file system is read-only.", path); + + return log_error_errno(errno, "Failed to create timestamp file %s: %m", path); + } + + (void) loop_write(fd, MESSAGE, strlen(MESSAGE), false); + + if (futimens(fd, twice) < 0) + return log_error_errno(errno, "Failed to update timestamp on %s: %m", path); + } else + log_error_errno(errno, "Failed to stat() timestamp file %s: %m", path); + + return 0; +} + +int main(int argc, char *argv[]) { + struct stat st; + int r, q = 0; + + log_set_target(LOG_TARGET_AUTO); + log_parse_environment(); + log_open(); + + if (stat("/usr", &st) < 0) { + log_error_errno(errno, "Failed to stat /usr: %m"); + return EXIT_FAILURE; + } + + r = mac_selinux_init(NULL); + if (r < 0) { + log_error_errno(r, "SELinux setup failed: %m"); + goto finish; + } + + r = apply_timestamp("/etc/.updated", &st.st_mtim); + q = apply_timestamp("/var/.updated", &st.st_mtim); + +finish: + return r < 0 || q < 0 ? EXIT_FAILURE : EXIT_SUCCESS; +} |