diff options
Diffstat (limited to 'src/grp-journal/systemd-cat/cat.c')
| -rw-r--r-- | src/grp-journal/systemd-cat/cat.c | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/src/grp-journal/systemd-cat/cat.c b/src/grp-journal/systemd-cat/cat.c new file mode 100644 index 0000000000..105d42591e --- /dev/null +++ b/src/grp-journal/systemd-cat/cat.c @@ -0,0 +1,161 @@ +/*** + This file is part of systemd. + + Copyright 2012 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 <errno.h> +#include <fcntl.h> +#include <getopt.h> +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> + +#include <systemd/sd-journal.h> + +#include "systemd-basic/fd-util.h" +#include "systemd-basic/parse-util.h" +#include "systemd-basic/string-util.h" +#include "systemd-basic/syslog-util.h" +#include "systemd-basic/util.h" + +static const char *arg_identifier = NULL; +static int arg_priority = LOG_INFO; +static bool arg_level_prefix = true; + +static void help(void) { + printf("%s [OPTIONS...] {COMMAND} ...\n\n" + "Execute process with stdout/stderr connected to the journal.\n\n" + " -h --help Show this help\n" + " --version Show package version\n" + " -t --identifier=STRING Set syslog identifier\n" + " -p --priority=PRIORITY Set priority value (0..7)\n" + " --level-prefix=BOOL Control whether level prefix shall be parsed\n" + , program_invocation_short_name); +} + +static int parse_argv(int argc, char *argv[]) { + + enum { + ARG_VERSION = 0x100, + ARG_LEVEL_PREFIX + }; + + static const struct option options[] = { + { "help", no_argument, NULL, 'h' }, + { "version", no_argument, NULL, ARG_VERSION }, + { "identifier", required_argument, NULL, 't' }, + { "priority", required_argument, NULL, 'p' }, + { "level-prefix", required_argument, NULL, ARG_LEVEL_PREFIX }, + {} + }; + + int c; + + assert(argc >= 0); + assert(argv); + + while ((c = getopt_long(argc, argv, "+ht:p:", options, NULL)) >= 0) + + switch (c) { + + case 'h': + help(); + return 0; + + case ARG_VERSION: + return version(); + + case 't': + if (isempty(optarg)) + arg_identifier = NULL; + else + arg_identifier = optarg; + break; + + case 'p': + arg_priority = log_level_from_string(optarg); + if (arg_priority < 0) { + log_error("Failed to parse priority value."); + return -EINVAL; + } + break; + + case ARG_LEVEL_PREFIX: { + int k; + + k = parse_boolean(optarg); + if (k < 0) + return log_error_errno(k, "Failed to parse level prefix value."); + + arg_level_prefix = k; + break; + } + + case '?': + return -EINVAL; + + default: + assert_not_reached("Unhandled option"); + } + + return 1; +} + +int main(int argc, char *argv[]) { + _cleanup_close_ int fd = -1, saved_stderr = -1; + int r; + + log_parse_environment(); + log_open(); + + r = parse_argv(argc, argv); + if (r <= 0) + goto finish; + + fd = sd_journal_stream_fd(arg_identifier, arg_priority, arg_level_prefix); + if (fd < 0) { + r = log_error_errno(fd, "Failed to create stream fd: %m"); + goto finish; + } + + saved_stderr = fcntl(STDERR_FILENO, F_DUPFD_CLOEXEC, 3); + + if (dup3(fd, STDOUT_FILENO, 0) < 0 || + dup3(fd, STDERR_FILENO, 0) < 0) { + r = log_error_errno(errno, "Failed to duplicate fd: %m"); + goto finish; + } + + if (fd >= 3) + safe_close(fd); + fd = -1; + + if (argc <= optind) + (void) execl("/bin/cat", "/bin/cat", NULL); + else + (void) execvp(argv[optind], argv + optind); + r = -errno; + + /* Let's try to restore a working stderr, so we can print the error message */ + if (saved_stderr >= 0) + (void) dup3(saved_stderr, STDERR_FILENO, 0); + + log_error_errno(r, "Failed to execute process: %m"); + +finish: + return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS; +} |