rc-update: add 'env' sub-command

allows users to export variables into the starting environment of services, with usage `rc-update env FOO NYA=MEW`
OpenRC · Mar 4, 2025 · 95ecd74 · 95ecd74
1 parent 5992833
commit 95ecd74
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Showing 2 changed files with 56 additions and 13 deletions.
diff --git a/man/rc-update.8 b/man/rc-update.8
@@ -27,6 +27,10 @@
 .Ar service
 .Op Ar runlevel ...
 .Nm
+.Op Fl a , -all
+.Ar env
+.Ar variable ...
+.Nm
 .Op Fl u , -update
 .Op Fl v , -verbose
 .Ar show
@@ -59,6 +63,10 @@ Delete the
 from the
 .Ar runlevel
 or the current one if none given.
+.It Ar env Ar variable ...
+Exports listed
+.Ar variables
+to the starting environment of all services.
 .It Ar show
 Show all enabled services and the runlevels they belong to.  If you specify
 runlevels to show, then only those will be included in the output.

diff --git a/src/rc-update/rc-update.c b/src/rc-update/rc-update.c
@@ -35,6 +35,7 @@ const char *extraopts = NULL;
 const char *usagestring = ""							\
 	"Usage: rc-update [options] add <service> [<runlevel>...]\n"	\
 	"   or: rc-update [options] del <service> [<runlevel>...]\n"	\
+	"   or: rc-update [options] env <variables>...\n"	\
 	"   or: rc-update [options] [show [<runlevel>...]]";
 const char getoptstring[] = "asu" getoptstring_COMMON;
 const struct option longopts[] = {
@@ -50,6 +51,8 @@ const char * const longopts_help[] = {
 	longopts_help_COMMON
 };
 
+extern const char **environ;
+
 /* Return the number of changes made:
  *  -1 = no changes (error)
  *   0 = no changes (nothing to do)
@@ -190,11 +193,26 @@ show(RC_STRINGLIST *runlevels, bool verbose)
 	rc_stringlist_free(services);
 }
 
+static void
+env(char *variable)
+{
+	char *value = variable;
+	variable = strsep(&value, "=");
+
+	if (!value && !(value = getenv(variable))) {
+		ewarn("%s: environment variable %s not set, skipping.", applet, variable);
+		return;
+	}
+
+	rc_export_variable(variable, value);
+}
+
 enum update_action {
 	DO_NONE,
 	DO_ADD,
 	DO_DELETE,
 	DO_SHOW,
+	DO_ENV
 };
 
 int main(int argc, char **argv)
@@ -205,7 +223,7 @@ int main(int argc, char **argv)
 	char *service = NULL;
 	char *p;
 	enum update_action action = DO_NONE;
-	bool verbose = false, stack = false, all_runlevels = false;
+	bool verbose = false, stack = false, all = false;
 	int opt;
 	int retval = EXIT_FAILURE;
 	int num_updated = 0;
@@ -216,7 +234,7 @@ int main(int argc, char **argv)
 	while ((opt = getopt_long(argc, argv, getoptstring, longopts, NULL)) != -1) {
 		switch (opt) {
 		case 'a':
-		    all_runlevels = true;
+		    all = true;
 		break;
 		case 's':
 		    stack = true;
@@ -239,6 +257,8 @@ int main(int argc, char **argv)
 			action = DO_DELETE;
 		else if (strcmp(argv[optind], "show") == 0)
 			action = DO_SHOW;
+		else if (strcmp(argv[optind], "env") == 0)
+			action = DO_ENV;
 		else
 			usage(EXIT_FAILURE);
 		optind++;
@@ -249,16 +269,18 @@ int main(int argc, char **argv)
 	if (optind >= argc && action != DO_SHOW)
 		usage(EXIT_FAILURE);
 
-	service = argv[optind];
-	optind++;
+	if (action != DO_ENV) {
+		service = argv[optind];
+		optind++;
 
-	runlevels = rc_stringlist_new();
-	while (optind < argc) {
-		if (rc_runlevel_exists(argv[optind])) {
-			rc_stringlist_add(runlevels, argv[optind++]);
-		} else {
-			rc_stringlist_free(runlevels);
-			eerrorx("%s: '%s' is not a valid runlevel", applet, argv[optind]);
+		runlevels = rc_stringlist_new();
+		while (optind < argc) {
+			if (rc_runlevel_exists(argv[optind])) {
+				rc_stringlist_add(runlevels, argv[optind++]);
+			} else {
+				rc_stringlist_free(runlevels);
+				eerrorx("%s: '%s' is not a valid runlevel", applet, argv[optind]);
+			}
 		}
 	}
 
@@ -279,8 +301,21 @@ int main(int argc, char **argv)
 		rc_stringlist_sort(&runlevels);
 		show(runlevels, verbose);
 		goto exit;
+	case DO_ENV:
+		if (all) {
+			for (const char **envptr = environ; *envptr; envptr++) {
+				char *var = xstrdup(*envptr);
+				env(var);
+				free(var);
+			}
+			return 0;
+		}
+
+		while (optind < argc)
+			env(argv[optind++]);
+		return 0;
 	case DO_ADD:
-		if (all_runlevels) {
+		if (all) {
 			rc_stringlist_free(runlevels);
 			eerrorx("%s: the -a option is invalid with add", applet);
 		}
@@ -292,7 +327,7 @@ int main(int argc, char **argv)
 	}
 
 	if (!TAILQ_FIRST(runlevels)) {
-		if (all_runlevels) {
+		if (all) {
 			free(runlevels);
 			runlevels = rc_runlevel_list();
 		} else {