Merge pull request #18375 from yuwata/cli-tools-also-read-kernel-command-line

tree-wide: make CLI tools also read kernel command line when run as service

man/systemd.exec.xml

@@ -3043,6 +3043,17 @@ StandardInputData=SWNrIHNpdHplIGRhIHVuJyBlc3NlIEtsb3BzLAp1ZmYgZWVtYWwga2xvcHAncy
           </para></listitem>
         </varlistentry>
 
+        <varlistentry>
+          <term><varname>$SYSTEMD_EXEC_PID</varname></term>
+
+          <listitem><para>The PID of the unit process (e.g. process invoked by
+          <varname>ExecStart=</varname>). The child process can use this information to determine
+          whether the process is directly invoked by the service manager or indirectly as a child of
+          another process by comparing this value with the current PID (as similar to the scheme used in
+          <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+          with <varname>$LISTEN_PID</varname> and <varname>$LISTEN_FDS</varname>).</para></listitem>
+        </varlistentry>
+
         <varlistentry>
           <term><varname>$TERM</varname></term>
 

src/analyze/analyze.c

@@ -2446,7 +2446,7 @@ static int run(int argc, char *argv[]) {
         setlocale(LC_ALL, "");
         setlocale(LC_NUMERIC, "C"); /* we want to format/parse floats in C style */
 
-        log_setup_cli();
+        log_setup();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/backlight/backlight.c

@@ -380,7 +380,7 @@ static int run(int argc, char *argv[]) {
         unsigned max_brightness, brightness;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         if (strv_contains(strv_skip(argv, 1), "--help"))
                 return help();

src/basic/env-util.c

@@ -12,6 +12,8 @@
 #include "extract-word.h"
 #include "macro.h"
 #include "parse-util.h"
+#include "process-util.h"
+#include "stdio-util.h"
 #include "string-util.h"
 #include "strv.h"
 #include "utf8.h"
@@ -749,3 +751,24 @@ int set_unset_env(const char *name, const char *value, bool overwrite) {
                 return -errno;
         return 0;
 }
+
+int setenv_systemd_exec_pid(bool update_only) {
+        char str[DECIMAL_STR_MAX(pid_t)];
+        const char *e;
+
+        /* Update $SYSTEMD_EXEC_PID=pid except when '*' is set for the variable. */
+
+        e = secure_getenv("SYSTEMD_EXEC_PID");
+        if (!e && update_only)
+                return 0;
+
+        if (streq_ptr(e, "*"))
+                return 0;
+
+        xsprintf(str, PID_FMT, getpid_cached());
+
+        if (setenv("SYSTEMD_EXEC_PID", str, 1) < 0)
+                return -errno;
+
+        return 1;
+}

src/basic/env-util.h

@@ -55,3 +55,5 @@ int getenv_bool_secure(const char *p);
 
 /* Like setenv, but calls unsetenv if value == NULL. */
 int set_unset_env(const char *name, const char *value, bool overwrite);
+
+int setenv_systemd_exec_pid(bool update_only);

src/basic/log.c

@@ -1157,20 +1157,38 @@ static int parse_proc_cmdline_item(const char *key, const char *value, void *dat
         return 0;
 }
 
-void log_parse_environment(void) {
-        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);
+static bool should_parse_proc_cmdline(void) {
+        const char *e;
+        pid_t p;
 
-        log_parse_environment_cli();
+        /* PID1 always reads the kernel command line. */
+        if (getpid_cached() == 1)
+                return true;
+
+        /* If the process is directly executed by PID1 (e.g. ExecStart= or generator), systemd-importd,
+         * or systemd-homed, then $SYSTEMD_EXEC_PID= is set, and read the command line. */
+        e = getenv("SYSTEMD_EXEC_PID");
+        if (!e)
+                return false;
+
+        if (streq(e, "*"))
+                /* For testing. */
+                return true;
+
+        if (parse_pid(e, &p) < 0)
+                /* We know that systemd sets the variable correctly. Something else must have set it. */
+                log_debug("Failed to parse \"$SYSTEMD_EXEC_PID=%s\". Ignoring.", e);
+
+        return getpid_cached() == p;
 }
 
-void log_parse_environment_cli(void) {
+void log_parse_environment(void) {
+        const char *e;
+
         /* Do not call from library code. */
 
-        const char *e;
+        if (should_parse_proc_cmdline())
+                (void) proc_cmdline_parse(parse_proc_cmdline_item, NULL, PROC_CMDLINE_STRIP_RD_PREFIX);
 
         e = getenv("SYSTEMD_LOG_TARGET");
         if (e && log_set_target_from_string(e) < 0)
@@ -1460,22 +1478,10 @@ int log_dup_console(void) {
         return 0;
 }
 
-void log_setup_service(void) {
-        /* Sets up logging the way it is most appropriate for running a program as a service. Note that using this
-         * doesn't make the binary unsuitable for invocation on the command line, as log output will still go to the
-         * terminal if invoked interactively. */
-
+void log_setup(void) {
         log_set_target(LOG_TARGET_AUTO);
         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_set_target(LOG_TARGET_AUTO);
-        log_parse_environment_cli();
-        (void) log_open();
         if (log_on_console() && show_color < 0)
                 log_show_color(true);
 }

src/basic/log.h

@@ -69,7 +69,6 @@ void log_close(void);
 void log_forget_fds(void);
 
 void log_parse_environment(void);
-void log_parse_environment_cli(void);
 
 int log_dispatch_internal(
                 int level,
@@ -301,5 +300,4 @@ 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);
+void log_setup(void);

src/binfmt/binfmt.c

@@ -190,7 +190,7 @@ static int run(int argc, char *argv[]) {
         if (r <= 0)
                 return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/busctl/busctl.c

@@ -2565,7 +2565,7 @@ static int busctl_main(int argc, char *argv[]) {
 static int run(int argc, char *argv[]) {
         int r;
 
-        log_setup_cli();
+        log_setup();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/cgls/cgls.c

@@ -163,7 +163,7 @@ static void show_cg_info(const char *controller, const char *path) {
 static int run(int argc, char *argv[]) {
         int r, output_flags;
 
-        log_setup_cli();
+        log_setup();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/cgroups-agent/cgroups-agent.c

@@ -22,7 +22,7 @@ int main(int argc, char *argv[]) {
                 return EXIT_FAILURE;
         }
 
-        log_setup_service();
+        log_setup();
 
         fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0);
         if (fd < 0) {

src/cgtop/cgtop.c

@@ -915,7 +915,7 @@ static int run(int argc, char *argv[]) {
         CGroupMask mask;
         int r;
 
-        log_setup_cli();
+        log_setup();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/core/execute.c

@@ -1794,7 +1794,7 @@ static int build_environment(
         assert(p);
         assert(ret);
 
-#define N_ENV_VARS 16
+#define N_ENV_VARS 17
         our_env = new0(char*, N_ENV_VARS + _EXEC_DIRECTORY_TYPE_MAX);
         if (!our_env)
                 return -ENOMEM;
@@ -1950,6 +1950,11 @@ static int build_environment(
                 our_env[n_env++] = x;
         }
 
+        if (asprintf(&x, "SYSTEMD_EXEC_PID=" PID_FMT, getpid_cached()) < 0)
+                return -ENOMEM;
+
+        our_env[n_env++] = x;
+
         our_env[n_env++] = NULL;
         assert(n_env <= N_ENV_VARS + _EXEC_DIRECTORY_TYPE_MAX);
 #undef N_ENV_VARS

src/core/manager.c

@@ -4108,7 +4108,8 @@ static int manager_run_environment_generators(Manager *m) {
 
         RUN_WITH_UMASK(0022)
                 r = execute_directories((const char* const*) paths, DEFAULT_TIMEOUT_USEC, gather_environment,
-                                        args, NULL, m->transient_environment, EXEC_DIR_PARALLEL | EXEC_DIR_IGNORE_ERRORS);
+                                        args, NULL, m->transient_environment,
+                                        EXEC_DIR_PARALLEL | EXEC_DIR_IGNORE_ERRORS | EXEC_DIR_SET_SYSTEMD_EXEC_PID);
         return r;
 }
 
@@ -4143,7 +4144,8 @@ static int manager_run_generators(Manager *m) {
 
         RUN_WITH_UMASK(0022)
                 (void) execute_directories((const char* const*) paths, DEFAULT_TIMEOUT_USEC, NULL, NULL,
-                                           (char**) argv, m->transient_environment, EXEC_DIR_PARALLEL | EXEC_DIR_IGNORE_ERRORS);
+                                           (char**) argv, m->transient_environment,
+                                           EXEC_DIR_PARALLEL | EXEC_DIR_IGNORE_ERRORS | EXEC_DIR_SET_SYSTEMD_EXEC_PID);
 
         r = 0;
 

src/coredump/coredump.c

@@ -861,7 +861,7 @@ static int process_socket(int fd) {
 
         assert(fd >= 0);
 
-        log_setup_service();
+        log_setup();
 
         log_debug("Processing coredump received on stdin...");
 

src/coredump/coredumpctl.c

@@ -1108,7 +1108,7 @@ static int run(int argc, char *argv[]) {
         int r, units_active;
 
         setlocale(LC_ALL, "");
-        log_setup_cli();
+        log_setup();
 
         /* The journal merging logic potentially needs a lot of fds. */
         (void) rlimit_nofile_bump(HIGH_RLIMIT_NOFILE);

src/cryptsetup/cryptsetup.c

@@ -1395,7 +1395,7 @@ static int run(int argc, char *argv[]) {
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                        "This program requires at least two arguments.");
 
-        log_setup_service();
+        log_setup();
 
         cryptsetup_enable_logging(cd);
 

src/delta/delta.c

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

src/detect-virt/detect-virt.c

@@ -127,7 +127,7 @@ static int run(int argc, char *argv[]) {
          * to detect whether we are being run in a virtualized
          * environment or not */
 
-        log_setup_cli();
+        log_setup();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/escape/escape.c

@@ -158,7 +158,7 @@ static int run(int argc, char *argv[]) {
         char **i;
         int r;
 
-        log_setup_cli();
+        log_setup();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/firstboot/firstboot.c

@@ -1271,7 +1271,7 @@ static int run(int argc, char *argv[]) {
         if (r <= 0)
                 return r;
 
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/fsck/fsck.c

@@ -256,7 +256,7 @@ static int run(int argc, char *argv[]) {
         int r, exit_status;
         pid_t pid;
 
-        log_setup_service();
+        log_setup();
 
         if (argc > 2)
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),

src/hibernate-resume/hibernate-resume.c

@@ -20,7 +20,7 @@ int main(int argc, char *argv[]) {
                 return EXIT_FAILURE;
         }
 
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/home/homectl.c

@@ -3346,7 +3346,7 @@ static int run(int argc, char *argv[]) {
 
         int r;
 
-        log_setup_cli();
+        log_setup();
 
         r = redirect_bus_mgr();
         if (r < 0)

src/home/homed-home.c

@@ -1038,6 +1038,10 @@ static int home_start_work(Home *h, const char *verb, UserRecord *hr, UserRecord
                                 _exit(EXIT_FAILURE);
                         }
 
+                r = setenv_systemd_exec_pid(true);
+                if (r < 0)
+                        log_warning_errno(r, "Failed to update $SYSTEMD_EXEC_PID, ignoring: %m");
+
                 r = rearrange_stdio(stdin_fd, stdout_fd, STDERR_FILENO);
                 if (r < 0) {
                         log_error_errno(r, "Failed to rearrange stdin/stdout/stderr: %m");

src/home/homed.c

@@ -17,7 +17,7 @@ static int run(int argc, char *argv[]) {
         _cleanup_(notify_on_cleanup) const char *notify_stop = NULL;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         r = service_parse_argv("systemd-homed.service",
                                "A service to create, remove, change or inspect home areas.",

src/home/homework.c

@@ -1633,7 +1633,7 @@ static int run(int argc, char *argv[]) {
 
         start = now(CLOCK_MONOTONIC);
 
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/hostname/hostnamectl.c

@@ -443,7 +443,7 @@ static int run(int argc, char *argv[]) {
         int r;
 
         setlocale(LC_ALL, "");
-        log_setup_cli();
+        log_setup();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/hostname/hostnamed.c

@@ -1064,7 +1064,7 @@ static int run(int argc, char *argv[]) {
         _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         r = service_parse_argv("systemd-hostnamed.service",
                                "Manage the system hostname and related metadata.",

src/id128/id128.c

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

src/import/importd.c

@@ -11,6 +11,7 @@
 #include "bus-log-control-api.h"
 #include "bus-polkit.h"
 #include "def.h"
+#include "env-util.h"
 #include "fd-util.h"
 #include "float.h"
 #include "hostname-util.h"
@@ -403,6 +404,10 @@ static int transfer_start(Transfer *t) {
                         _exit(EXIT_FAILURE);
                 }
 
+                r = setenv_systemd_exec_pid(true);
+                if (r < 0)
+                        log_warning_errno(r, "Failed to update $SYSTEMD_EXEC_PID, ignoring: %m");
+
                 switch (t->type) {
 
                 case TRANSFER_IMPORT_TAR:
@@ -1361,7 +1366,7 @@ static int run(int argc, char *argv[]) {
         _cleanup_(manager_unrefp) Manager *m = NULL;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         r = service_parse_argv("systemd-importd.service",
                                "VM and container image import and export service.",

src/initctl/initctl.c

@@ -317,7 +317,7 @@ static int run(int argc, char *argv[]) {
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                        "This program does not take arguments.");
 
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/journal-remote/journal-gatewayd.c

@@ -995,7 +995,7 @@ static int run(int argc, char *argv[]) {
                 MHD_USE_THREAD_PER_CONNECTION;
         int r, n;
 
-        log_setup_service();
+        log_setup();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

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

@@ -1121,7 +1121,7 @@ static int run(int argc, char **argv) {
         int r;
 
         log_show_color(true);
-        log_parse_environment_cli();
+        log_parse_environment();
 
         /* The journal merging logic potentially needs a lot of fds. */
         (void) rlimit_nofile_bump(HIGH_RLIMIT_NOFILE);

src/journal-remote/journal-upload.c

@@ -820,7 +820,7 @@ static int run(int argc, char **argv) {
         int r;
 
         log_show_color(true);
-        log_parse_environment_cli();
+        log_parse_environment();
 
         /* The journal merging logic potentially needs a lot of fds. */
         (void) rlimit_nofile_bump(HIGH_RLIMIT_NOFILE);

src/journal/cat.c

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

src/journal/journalctl.c

@@ -2145,7 +2145,7 @@ int main(int argc, char *argv[]) {
         int n_shown = 0, r, poll_fd = -1;
 
         setlocale(LC_ALL, "");
-        log_setup_cli();
+        log_setup();
 
         /* 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

@@ -506,7 +506,7 @@ static int run(int argc, char *argv[]) {
         int r;
 
         setlocale(LC_ALL, "");
-        log_setup_cli();
+        log_setup();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/locale/localed.c

@@ -830,7 +830,7 @@ static int run(int argc, char *argv[]) {
         _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         r = service_parse_argv("systemd-localed.service",
                                "Manage system locale settings and key mappings.",

src/login/loginctl.c

@@ -1464,7 +1464,7 @@ static int run(int argc, char *argv[]) {
         int r;
 
         setlocale(LC_ALL, "");
-        log_setup_cli();
+        log_setup();
 
         /* The journal merging logic potentially needs a lot of fds. */
         (void) rlimit_nofile_bump(HIGH_RLIMIT_NOFILE);

src/login/logind.c

@@ -1160,7 +1160,7 @@ static int run(int argc, char *argv[]) {
         int r;
 
         log_set_facility(LOG_AUTH);
-        log_setup_service();
+        log_setup();
 
         r = service_parse_argv("systemd-logind.service",
                                "Manager for user logins and devices and privileged operations.",

src/machine/machinectl.c

@@ -2876,7 +2876,7 @@ static int run(int argc, char *argv[]) {
         int r;
 
         setlocale(LC_ALL, "");
-        log_setup_cli();
+        log_setup();
 
         /* The journal merging logic potentially needs a lot of fds. */
         (void) rlimit_nofile_bump(HIGH_RLIMIT_NOFILE);

src/machine/machined.c

@@ -324,7 +324,7 @@ static int run(int argc, char *argv[]) {
         int r;
 
         log_set_facility(LOG_AUTH);
-        log_setup_service();
+        log_setup();
 
         r = service_parse_argv("systemd-machined.service",
                                "Manage registrations of local VMs and containers.",

src/modules-load/modules-load.c

@@ -165,7 +165,7 @@ static int run(int argc, char *argv[]) {
         if (r <= 0)
                 return r;
 
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/network/networkctl.c

@@ -2822,7 +2822,7 @@ static void warn_networkd_missing(void) {
 static int run(int argc, char* argv[]) {
         int r;
 
-        log_setup_cli();
+        log_setup();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/network/networkd.c

@@ -22,7 +22,7 @@ static int run(int argc, char *argv[]) {
         _cleanup_(notify_on_cleanup) const char *notify_message = NULL;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/network/wait-online/wait-online.c

@@ -184,7 +184,7 @@ static int run(int argc, char *argv[]) {
         _cleanup_(notify_on_cleanup) const char *notify_message = NULL;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/oom/oomd.c

@@ -122,7 +122,7 @@ static int run(int argc, char *argv[]) {
         unsigned long long s = 0;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/partition/growfs.c

@@ -201,7 +201,7 @@ static int run(int argc, char *argv[]) {
         dev_t devno;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/partition/makefs.c

@@ -24,7 +24,7 @@ static int run(int argc, char *argv[]) {
         struct stat st;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         if (argc != 3)
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),

src/portable/portablectl.c

@@ -1113,7 +1113,7 @@ static int run(int argc, char *argv[]) {
 
         int r;
 
-        log_setup_cli();
+        log_setup();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/portable/portabled.c

@@ -135,7 +135,7 @@ static int run(int argc, char *argv[]) {
         _cleanup_(manager_unrefp) Manager *m = NULL;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/pstore/pstore.c

@@ -367,7 +367,7 @@ static int run(int argc, char *argv[]) {
         _cleanup_(pstore_entries_reset) PStoreList list = {};
         int r;
 
-        log_setup_service();
+        log_setup();
 
         if (argc == 3) {
                 arg_sourcedir = argv[1];

src/quotacheck/quotacheck.c

@@ -58,7 +58,7 @@ static void test_files(void) {
 static int run(int argc, char *argv[]) {
         int r;
 
-        log_setup_service();
+        log_setup();
 
         if (argc > 1)
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),

src/random-seed/random-seed.c

@@ -110,7 +110,7 @@ static int run(int argc, char *argv[]) {
         ssize_t k;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         if (argc != 2)
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),

src/remount-fs/remount-fs.c

@@ -77,7 +77,7 @@ static int run(int argc, char *argv[]) {
         struct mntent* me;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         if (argc > 1)
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),

src/reply-password/reply-password.c

@@ -39,7 +39,7 @@ static int run(int argc, char *argv[]) {
         size_t length = 0;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         if (argc != 3)
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Wrong number of arguments.");

src/resolve/resolvectl.c

@@ -3296,7 +3296,7 @@ static int run(int argc, char **argv) {
         int r;
 
         setlocale(LC_ALL, "");
-        log_setup_cli();
+        log_setup();
 
         if (streq(program_invocation_short_name, "resolvconf"))
                 r = resolvconf_parse_argv(argc, argv);

src/resolve/resolved.c

@@ -26,7 +26,7 @@ static int run(int argc, char *argv[]) {
         _cleanup_(notify_on_cleanup) const char *notify_stop = NULL;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         r = service_parse_argv("systemd-resolved.service",
                                "Provide name resolution with caching using DNS, mDNS, LLMNR.",

src/rfkill/rfkill.c

@@ -276,7 +276,7 @@ static int run(int argc, char *argv[]) {
         if (argc > 1)
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "This program requires no arguments.");
 
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/shared/exec-util.c

@@ -34,7 +34,7 @@
 /* Put this test here for a lack of better place */
 assert_cc(EAGAIN == EWOULDBLOCK);
 
-static int do_spawn(const char *path, char *argv[], int stdout_fd, pid_t *pid) {
+static int do_spawn(const char *path, char *argv[], int stdout_fd, pid_t *pid, bool set_systemd_exec_pid) {
         pid_t _pid;
         int r;
 
@@ -57,6 +57,12 @@ static int do_spawn(const char *path, char *argv[], int stdout_fd, pid_t *pid) {
 
                 (void) rlimit_nofile_safe();
 
+                if (set_systemd_exec_pid) {
+                        r = setenv_systemd_exec_pid(false);
+                        if (r < 0)
+                                log_warning_errno(r, "Failed to set $SYSTEMD_EXEC_PID, ignoring: %m");
+                }
+
                 if (!argv) {
                         _argv[0] = (char*) path;
                         _argv[1] = NULL;
@@ -132,7 +138,7 @@ static int do_execute(
                                 return log_error_errno(fd, "Failed to open serialization file: %m");
                 }
 
-                r = do_spawn(t, argv, fd, &pid);
+                r = do_spawn(t, argv, fd, &pid, FLAGS_SET(flags, EXEC_DIR_SET_SYSTEMD_EXEC_PID));
                 if (r <= 0)
                         continue;
 

src/shared/exec-util.h

@@ -15,9 +15,10 @@ enum {
 };
 
 typedef enum {
-        EXEC_DIR_NONE          = 0,      /* No execdir flags */
-        EXEC_DIR_PARALLEL      = 1 << 0, /* Execute scripts in parallel, if possible */
-        EXEC_DIR_IGNORE_ERRORS = 1 << 1, /* Ignore non-zero exit status of scripts */
+        EXEC_DIR_NONE                 = 0,      /* No execdir flags */
+        EXEC_DIR_PARALLEL             = 1 << 0, /* Execute scripts in parallel, if possible */
+        EXEC_DIR_IGNORE_ERRORS        = 1 << 1, /* Ignore non-zero exit status of scripts */
+        EXEC_DIR_SET_SYSTEMD_EXEC_PID = 1 << 2, /* Set $SYSTEMD_EXEC_PID environment variable */
 } ExecDirFlags;
 
 typedef enum ExecCommandFlags {

src/sleep/sleep.c

@@ -368,7 +368,7 @@ static int run(int argc, char *argv[]) {
         _cleanup_(free_sleep_configp) SleepConfig *sleep_config = NULL;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/sulogin-shell/sulogin-shell.c

@@ -100,7 +100,7 @@ int main(int argc, char *argv[]) {
         _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         print_mode(argc > 1 ? argv[1] : "");
 

src/sysctl/sysctl.c

@@ -386,7 +386,7 @@ static int run(int argc, char *argv[]) {
         if (r <= 0)
                 return r;
 
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/sysext/sysext.c

@@ -1027,7 +1027,7 @@ static int sysext_main(int argc, char *argv[]) {
 static int run(int argc, char *argv[]) {
         int r;
 
-        log_setup_cli();
+        log_setup();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/systemctl/systemctl.c

@@ -1085,7 +1085,7 @@ static int run(int argc, char *argv[]) {
         int r;
 
         setlocale(LC_ALL, "");
-        log_parse_environment_cli();
+        log_parse_environment();
         log_open();
 
         /* The journal merging logic potentially needs a lot of fds. */

src/sysusers/sysusers.c

@@ -1928,7 +1928,7 @@ static int run(int argc, char *argv[]) {
         if (r <= 0)
                 return r;
 
-        log_setup_service();
+        log_setup();
 
         if (arg_cat_config)
                 return cat_config();

src/test/test-chase-symlinks.c

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

src/test/test-env-util.c

@@ -4,9 +4,12 @@
 #include "fd-util.h"
 #include "fileio.h"
 #include "fs-util.h"
+#include "parse-util.h"
+#include "process-util.h"
 #include "serialize.h"
 #include "string-util.h"
 #include "strv.h"
+#include "tests.h"
 #include "util.h"
 
 static void test_strv_env_delete(void) {
@@ -334,7 +337,44 @@ static void test_env_assignment_is_valid(void) {
         assert_se(!env_assignment_is_valid("głąb=printf \"\x1b]0;<mock-chroot>\x07<mock-chroot>\""));
 }
 
+static void test_setenv_systemd_exec_pid(void) {
+        _cleanup_free_ char *saved = NULL;
+        const char *e;
+        pid_t p;
+
+        log_info("/* %s */", __func__);
+
+        e = getenv("SYSTEMD_EXEC_PID");
+        if (e)
+                assert_se(saved = strdup(e));
+
+        assert_se(unsetenv("SYSTEMD_EXEC_PID") >= 0);
+        assert_se(setenv_systemd_exec_pid(true) == 0);
+        assert_se(!getenv("SYSTEMD_EXEC_PID"));
+
+        assert_se(setenv("SYSTEMD_EXEC_PID", "*", 1) >= 0);
+        assert_se(setenv_systemd_exec_pid(true) == 0);
+        assert_se(e = getenv("SYSTEMD_EXEC_PID"));
+        assert_se(streq(e, "*"));
+
+        assert_se(setenv("SYSTEMD_EXEC_PID", "123abc", 1) >= 0);
+        assert_se(setenv_systemd_exec_pid(true) == 1);
+        assert_se(e = getenv("SYSTEMD_EXEC_PID"));
+        assert_se(parse_pid(e, &p) >= 0);
+        assert_se(p == getpid_cached());
+
+        assert_se(unsetenv("SYSTEMD_EXEC_PID") >= 0);
+        assert_se(setenv_systemd_exec_pid(false) == 1);
+        assert_se(e = getenv("SYSTEMD_EXEC_PID"));
+        assert_se(parse_pid(e, &p) >= 0);
+        assert_se(p == getpid_cached());
+
+        assert_se(set_unset_env("SYSTEMD_EXEC_PID", saved, 1) >= 0);
+}
+
 int main(int argc, char *argv[]) {
+        test_setup_logging(LOG_DEBUG);
+
         test_strv_env_delete();
         test_strv_env_get();
         test_strv_env_unset();
@@ -350,6 +390,7 @@ int main(int argc, char *argv[]) {
         test_env_name_is_valid();
         test_env_value_is_valid();
         test_env_assignment_is_valid();
+        test_setenv_systemd_exec_pid();
 
         return 0;
 }

src/timedate/timedatectl.c

@@ -1051,7 +1051,7 @@ static int run(int argc, char *argv[]) {
         int r;
 
         setlocale(LC_ALL, "");
-        log_setup_cli();
+        log_setup();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/timedate/timedated.c

@@ -1109,7 +1109,7 @@ static int run(int argc, char *argv[]) {
         _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         r = service_parse_argv("systemd-timedated.service",
                                "Manage the system clock and timezone and NTP enablement.",

src/timesync/timesyncd.c

@@ -97,7 +97,7 @@ static int run(int argc, char *argv[]) {
         int r;
 
         log_set_facility(LOG_CRON);
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/tmpfiles/tmpfiles.c

@@ -3363,7 +3363,7 @@ static int run(int argc, char *argv[]) {
         if (r <= 0)
                 return r;
 
-        log_setup_service();
+        log_setup();
 
         /* Descending down file system trees might take a lot of fds */
         (void) rlimit_nofile_bump(HIGH_RLIMIT_NOFILE);

src/tty-ask-password-agent/tty-ask-password-agent.c

@@ -684,7 +684,7 @@ static int ask_on_consoles(char *argv[]) {
 static int run(int argc, char *argv[]) {
         int r;
 
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/update-done/update-done.c

@@ -41,7 +41,7 @@ int main(int argc, char *argv[]) {
         struct stat st;
         int r, q = 0;
 
-        log_setup_service();
+        log_setup();
 
         if (stat("/usr", &st) < 0) {
                 log_error_errno(errno, "Failed to stat /usr: %m");

src/update-utmp/update-utmp.c

@@ -224,7 +224,7 @@ static int run(int argc, char *argv[]) {
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                        "This program requires one argument.");
 
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/user-sessions/user-sessions.c

@@ -21,7 +21,7 @@ static int run(int argc, char *argv[]) {
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                        "This program requires one argument.");
 
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/userdb/userdbctl.c

@@ -763,7 +763,7 @@ static int run(int argc, char *argv[]) {
 
         int r;
 
-        log_setup_cli();
+        log_setup();
 
         r = parse_argv(argc, argv);
         if (r <= 0)

src/userdb/userdbd.c

@@ -24,7 +24,7 @@ static int run(int argc, char *argv[]) {
         _cleanup_(notify_on_cleanup) const char *notify_stop = NULL;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/userdb/userwork.c

@@ -662,7 +662,7 @@ static int run(int argc, char *argv[]) {
         unsigned n_iterations = 0;
         int m, listen_fd, r;
 
-        log_setup_service();
+        log_setup();
 
         m = sd_listen_fds(false);
         if (m < 0)

src/vconsole/vconsole-setup.c

@@ -430,7 +430,7 @@ int main(int argc, char **argv) {
         unsigned idx = 0;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/veritysetup/veritysetup.c

@@ -136,7 +136,7 @@ static int run(int argc, char *argv[]) {
         if (argc < 3)
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "This program requires at least two arguments.");
 
-        log_setup_service();
+        log_setup();
 
         umask(0022);
 

src/volatile-root/volatile-root.c

@@ -119,7 +119,7 @@ static int run(int argc, char *argv[]) {
         dev_t devt;
         int r;
 
-        log_setup_service();
+        log_setup();
 
         if (argc > 3)
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),