Merge pull request #3526 from fbuihuu/fix-console-log-color

Fix console log color

src/core/main.c

@@ -1294,6 +1294,35 @@ static int bump_unix_max_dgram_qlen(void) {
         return 1;
 }
 
+static int fixup_environment(void) {
+        _cleanup_free_ char *term = NULL;
+        int r;
+
+        /* When started as PID1, the kernel uses /dev/console
+         * for our stdios and uses TERM=linux whatever the
+         * backend device used by the console. We try to make
+         * a better guess here since some consoles might not
+         * have support for color mode for example.
+         *
+         * However if TERM was configured through the kernel
+         * command line then leave it alone. */
+
+        r = get_proc_cmdline_key("TERM=", &term);
+        if (r < 0)
+                return r;
+
+        if (r == 0) {
+                term = strdup(default_term_for_tty("/dev/console") + 5);
+                if (!term)
+                        return -errno;
+        }
+
+        if (setenv("TERM", term, 1) < 0)
+                return -errno;
+
+        return 0;
+}
+
 int main(int argc, char *argv[]) {
         Manager *m = NULL;
         int r, retval = EXIT_FAILURE;
@@ -1353,7 +1382,6 @@ int main(int argc, char *argv[]) {
         saved_argv = argv;
         saved_argc = argc;
 
-        log_show_color(colors_enabled());
         log_set_upgrade_syslog_to_journal(true);
 
         /* Disable the umask logic */
@@ -1364,7 +1392,6 @@ int main(int argc, char *argv[]) {
 
                 /* Running outside of a container as PID 1 */
                 arg_system = true;
-                make_null_stdio();
                 log_set_target(LOG_TARGET_KMSG);
                 log_open();
 
@@ -1480,6 +1507,21 @@ int main(int argc, char *argv[]) {
                         (void) write_string_file("/proc/sys/kernel/core_pattern", "|/bin/false", 0);
         }
 
+        /* We expect the environment to be set correctly if run inside a
+         * container. */
+        if (arg_system && detect_container() <= 0) {
+                if (fixup_environment() < 0) {
+                        error_message = "Failed to fix up PID1 environment";
+                        goto finish;
+                }
+
+                /* Try to figure out if we can use colors with the console. No
+                 * need to do that for user instances since they never log
+                 * into the console. */
+                log_show_color(colors_enabled());
+                make_null_stdio();
+        }
+
         /* Initialize default unit */
         r = free_and_strdup(&arg_default_unit, SPECIAL_DEFAULT_TARGET);
         if (r < 0) {
@@ -1967,6 +2009,9 @@ finish:
                                 log_error_errno(r, "Failed to switch root, trying to continue: %m");
                 }
 
+                /* Reopen the console */
+                (void) make_console_stdio();
+
                 args_size = MAX(6, argc+1);
                 args = newa(const char*, args_size);
 
@@ -1992,10 +2037,6 @@ finish:
                         args[i++] = sfd;
                         args[i++] = NULL;
 
-                        /* do not pass along the environment we inherit from the kernel or initrd */
-                        if (switch_root_dir)
-                                (void) clearenv();
-
                         assert(i <= args_size);
 
                         /*
@@ -2018,9 +2059,6 @@ finish:
                 arg_serialization = safe_fclose(arg_serialization);
                 fds = fdset_free(fds);
 
-                /* Reopen the console */
-                (void) make_console_stdio();
-
                 for (j = 1, i = 1; j < (unsigned) argc; j++)
                         args[i++] = argv[j];
                 args[i++] = NULL;