log: introduce log_parse_environment_cli() and log_setup_cli()

Presently, CLI utilities such as systemctl will check whether they have a tty
attached or not to decide whether to parse /proc/cmdline or EFI variable
SystemdOptions looking for systemd.log_* entries.

But this check will be misleading if these tools are being launched by a
daemon, such as a monitoring daemon or automation service that runs in
background.

Make log handling of CLI tools uniform by never checking /proc/cmdline or EFI
variables to determine the logging level.

Furthermore, introduce a new log_setup_cli() shortcut to set up common options
used by most command-line utilities.

src/analyze/analyze.c

@@ -2376,9 +2376,7 @@ static int run(int argc, char *argv[]) {
         setlocale(LC_ALL, "");
         setlocale(LC_NUMERIC, "C"); /* we want to format/parse floats in C style */
 
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/basic/log.c

@@ -1146,16 +1146,20 @@ static int parse_proc_cmdline_item(const char *key, const char *value, void *dat
 }
 
 void log_parse_environment_realm(LogRealm realm) {
-        /* Do not call from library code. */
-
-        const char *e;
-
         if (getpid_cached() == 1 || get_ctty_devnr(0, NULL) < 0)
                 /* Only try to read the command line in daemons. We assume that anything that has a
                  * controlling tty is user stuff. For PID1 we do a special check in case it hasn't
                  * closed the console yet. */
                 (void) proc_cmdline_parse(parse_proc_cmdline_item, NULL, PROC_CMDLINE_STRIP_RD_PREFIX);
 
+        log_parse_environment_cli_realm(realm);
+}
+
+void log_parse_environment_cli_realm(LogRealm realm) {
+        /* Do not call from library code. */
+
+        const char *e;
+
         e = getenv("SYSTEMD_LOG_TARGET");
         if (e && log_set_target_from_string(e) < 0)
                 log_warning("Failed to parse log target '%s'. Ignoring.", e);
@@ -1430,3 +1434,11 @@ void log_setup_service(void) {
         log_parse_environment();
         (void) log_open();
 }
+
+void log_setup_cli(void) {
+        /* Sets up logging the way it is most appropriate for running a program as a CLI utility. */
+
+        log_show_color(true);
+        log_parse_environment_cli();
+        (void) log_open();
+}

src/basic/log.h

@@ -84,8 +84,11 @@ void log_close(void);
 void log_forget_fds(void);
 
 void log_parse_environment_realm(LogRealm realm);
+void log_parse_environment_cli_realm(LogRealm realm);
 #define log_parse_environment() \
         log_parse_environment_realm(LOG_REALM)
+#define log_parse_environment_cli() \
+        log_parse_environment_cli_realm(LOG_REALM)
 
 int log_dispatch_internal(
                 int level,
@@ -341,3 +344,4 @@ int log_syntax_invalid_utf8_internal(
 #define DEBUG_LOGGING _unlikely_(log_get_max_level() >= LOG_DEBUG)
 
 void log_setup_service(void);
+void log_setup_cli(void);

src/busctl/busctl.c

@@ -2598,9 +2598,7 @@ static int busctl_main(int argc, char *argv[]) {
 static int run(int argc, char *argv[]) {
         int r;
 
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/cgls/cgls.c

@@ -164,9 +164,7 @@ static void show_cg_info(const char *controller, const char *path) {
 static int run(int argc, char *argv[]) {
         int r, output_flags;
 
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/cgtop/cgtop.c

@@ -908,9 +908,7 @@ static int run(int argc, char *argv[]) {
         CGroupMask mask;
         int r;
 
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/coredump/coredumpctl.c

@@ -1091,9 +1091,7 @@ static int run(int argc, char *argv[]) {
         int r, units_active;
 
         setlocale(LC_ALL, "");
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         /* The journal merging logic potentially needs a lot of fds. */
         (void) rlimit_nofile_bump(HIGH_RLIMIT_NOFILE);

src/delta/delta.c

@@ -643,9 +643,7 @@ static int parse_argv(int argc, char *argv[]) {
 static int run(int argc, char *argv[]) {
         int r, k, n_found = 0;
 
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/detect-virt/detect-virt.c

@@ -128,9 +128,7 @@ static int run(int argc, char *argv[]) {
          * to detect whether we are being run in a virtualized
          * environment or not */
 
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/escape/escape.c

@@ -159,9 +159,7 @@ static int run(int argc, char *argv[]) {
         char **i;
         int r;
 
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/home/homectl.c

@@ -3489,9 +3489,7 @@ static int run(int argc, char *argv[]) {
 
         int r;
 
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/hostname/hostnamectl.c

@@ -436,9 +436,7 @@ static int run(int argc, char *argv[]) {
         int r;
 
         setlocale(LC_ALL, "");
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/id128/id128.c

@@ -249,9 +249,7 @@ static int id128_main(int argc, char *argv[]) {
 static int run(int argc, char *argv[]) {
         int r;
 
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/journal-remote/journal-remote-main.c

@@ -1110,7 +1110,7 @@ static int run(int argc, char **argv) {
         int r;
 
         log_show_color(true);
-        log_parse_environment();
+        log_parse_environment_cli();
 
         /* The journal merging logic potentially needs a lot of fds. */
         (void) rlimit_nofile_bump(HIGH_RLIMIT_NOFILE);

src/journal-remote/journal-upload.c

@@ -821,7 +821,7 @@ static int run(int argc, char **argv) {
         int r;
 
         log_show_color(true);
-        log_parse_environment();
+        log_parse_environment_cli();
 
         /* The journal merging logic potentially needs a lot of fds. */
         (void) rlimit_nofile_bump(HIGH_RLIMIT_NOFILE);

src/journal/cat.c

@@ -129,9 +129,7 @@ static int run(int argc, char *argv[]) {
         _cleanup_close_ int outfd = -1, errfd = -1, saved_stderr = -1;
         int r;
 
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/journal/journalctl.c

@@ -2115,9 +2115,7 @@ int main(int argc, char *argv[]) {
         int n_shown = 0, r, poll_fd = -1;
 
         setlocale(LC_ALL, "");
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         /* Increase max number of open files if we can, we might needs this when browsing journal files, which might be
          * split up into many files. */

src/locale/localectl.c

@@ -502,9 +502,7 @@ static int run(int argc, char *argv[]) {
         int r;
 
         setlocale(LC_ALL, "");
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/login/loginctl.c

@@ -1460,9 +1460,7 @@ static int run(int argc, char *argv[]) {
         int r;
 
         setlocale(LC_ALL, "");
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         /* The journal merging logic potentially needs a lot of fds. */
         (void) rlimit_nofile_bump(HIGH_RLIMIT_NOFILE);

src/machine/machinectl.c

@@ -2882,9 +2882,7 @@ static int run(int argc, char *argv[]) {
         int r;
 
         setlocale(LC_ALL, "");
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         /* The journal merging logic potentially needs a lot of fds. */
         (void) rlimit_nofile_bump(HIGH_RLIMIT_NOFILE);

src/network/networkctl.c

@@ -2818,9 +2818,7 @@ static void warn_networkd_missing(void) {
 static int run(int argc, char* argv[]) {
         int r;
 
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/portable/portablectl.c

@@ -1119,9 +1119,7 @@ static int run(int argc, char *argv[]) {
 
         int r;
 
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/resolve/resolvectl.c

@@ -3174,9 +3174,7 @@ static int run(int argc, char **argv) {
         int r;
 
         setlocale(LC_ALL, "");
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         if (streq(program_invocation_short_name, "resolvconf"))
                 r = resolvconf_parse_argv(argc, argv);

src/systemctl/systemctl.c

@@ -9207,7 +9207,7 @@ static int run(int argc, char *argv[]) {
         int r;
 
         setlocale(LC_ALL, "");
-        log_parse_environment();
+        log_parse_environment_cli();
         log_open();
 
         /* The journal merging logic potentially needs a lot of fds. */

src/test/test-chase-symlinks.c

@@ -84,9 +84,7 @@ static int parse_argv(int argc, char *argv[]) {
 static int run(int argc, char **argv) {
         int r;
 
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/timedate/timedatectl.c

@@ -1052,9 +1052,7 @@ static int run(int argc, char *argv[]) {
         int r;
 
         setlocale(LC_ALL, "");
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/userdb/userdbctl.c

@@ -761,9 +761,7 @@ static int run(int argc, char *argv[]) {
 
         int r;
 
-        log_show_color(true);
-        log_parse_environment();
-        log_open();
+        log_setup_cli();
 
         r = parse_argv(argc, argv);
         if (r <= 0)