refactor supervise-daemon into a proper supervisor with a root tree

src/librc/librc.c

@@ -1041,30 +1041,52 @@ rc_service_value_get(const char *service, const char *option)
 	return buffer;
 }
 
-bool
-rc_service_value_set(const char *service, const char *option, const char *value)
+static inline int
+open_optiondir(const char *service)
 {
-	bool ret = true;
-	int optdirfd;
+	if (mkdirat(rc_dirfd(RC_DIR_OPTIONS), service, 0755) != 0 && errno != EEXIST)
+		return -1;
+
+	return openat(rc_dirfd(RC_DIR_OPTIONS), service, O_RDONLY | O_DIRECTORY);
+}
+
+RC_PRINTF(3, 4) bool
+rc_service_value_fmt(const char *service, const char *option, const char *fmt, ...)
+{
+	int optdirfd = open_optiondir(service);
+	va_list ap;
 	FILE *fp;
 
-	if (mkdirat(rc_dirfd(RC_DIR_OPTIONS), service, 0755) != 0 && errno != EEXIST)
+	if (optdirfd == -1)
 		return false;
 
-	if ((optdirfd = openat(rc_dirfd(RC_DIR_OPTIONS), service, O_RDONLY | O_DIRECTORY)) == -1)
+	if (!(fp = do_fopenat(optdirfd, option, O_WRONLY | O_CREAT | O_TRUNC))) {
+		close(optdirfd);
 		return false;
+	}
 
-	if (!value) {
-		unlinkat(optdirfd, option, 0);
-	} else if ((fp = do_fopenat(optdirfd, option, O_WRONLY | O_CREAT | O_TRUNC))) {
-		fprintf(fp, "%s", value);
-		fclose(fp);
-	} else {
-		ret = false;
+	va_start(ap, fmt);
+	vfprintf(fp, fmt, ap);
+	va_end(ap);
+
+	fclose(fp);
+	return true;
+}
+
+bool
+rc_service_value_set(const char *service, const char *option, const char *value)
+{
+	int optdirfd;
+
+	if (value) {
+		return rc_service_value_fmt(service, option, "%s", value);
 	}
 
+	if ((optdirfd = open_optiondir(service)) == -1)
+		return false;
+	unlinkat(optdirfd, option, 0);
 	close(optdirfd);
-	return ret;
+	return true;
 }
 
 bool

src/librc/rc.h.in

@@ -340,6 +340,14 @@ bool rc_service_started_daemon(const char *, const char *,
  * @return saved value */
 char *rc_service_value_get(const char *, const char *);
 
+/*! Format and save a persistent value for a service
+ * @param service to save for
+ * @param option to save
+ * @param format string
+ * @return true if saved, otherwise false */
+__attribute__((__format__(__printf__, 3, 4)))
+bool rc_service_value_fmt(const char *, const char *, const char *, ...);
+
 /*! Save a persistent value for a service
  * @param service to save for
  * @param option to save

src/shared/helpers.h

@@ -78,6 +78,22 @@ RC_UNUSED static void *xrealloc(void *ptr, size_t size)
 	/* NOTREACHED */
 }
 
+RC_UNUSED static char *xstrndup(const char *str, size_t n)
+{
+	char *value;
+
+	if (!str)
+		return (NULL);
+
+	value = strndup(str, n);
+
+	if (value)
+		return (value);
+
+	ERRX;
+	/* NOTREACHED */
+}
+
 RC_UNUSED static char *xstrdup(const char *str)
 {
 	char *value;

src/shared/misc.c

@@ -375,7 +375,7 @@ exec_service(const char *service, const char *arg)
 }
 
 int
-parse_mode(mode_t *mode, char *text)
+parse_mode(mode_t *mode, const char *text)
 {
 	char *p;
 	unsigned long l;

src/shared/misc.h

@@ -76,7 +76,7 @@ int is_writable(const char *);
 #define service_start(service) exec_service(service, "start")
 #define service_stop(service)  exec_service(service, "stop")
 
-int parse_mode(mode_t *, char *);
+int parse_mode(mode_t *, const char *);
 
 /* Handy function so we can wrap einfo around our deptree */
 RC_DEPTREE *_rc_deptree_load (int, int *);

src/shared/rc_exec.c

@@ -167,13 +167,13 @@ int rc_waitpid(pid_t pid)
 	return status;
 }
 
-int rc_pipe_command(const char *cmd, int devnullfd)
+int rc_pipe_command(const char *cmd)
 {
 	const char *argv[] = { "/bin/sh", "-c", cmd, NULL };
 	struct exec_result res;
 	struct exec_args args = exec_init(argv);
 	args.redirect_stdin = EXEC_MKPIPE;
-	args.redirect_stdout = args.redirect_stderr = devnullfd;
+	args.redirect_stdout = args.redirect_stderr = EXEC_DEVNULL;
 	res = do_exec(&args);
 	return (res.pid > 0) ? res.proc_stdin : -1;
 }

src/shared/rc_exec.h

@@ -55,6 +55,6 @@ struct exec_result do_exec(struct exec_args *args);
 
 /* some exec related helplers */
 int rc_waitpid(pid_t pid);
-int rc_pipe_command(const char *cmd, int devnullfd);
+int rc_pipe_command(const char *cmd);
 
 #endif

src/shared/timeutils.c

@@ -69,6 +69,9 @@ int64_t parse_duration(const char *duration)
 	char *end;
 	long val;
 
+	if (!duration)
+		return 0;
+
 	errno = 0;
 	val = strtol(duration, &end, 10);
 	if (errno == ERANGE || *duration == '\0' || val < 0)

src/start-stop-daemon/start-stop-daemon.c

@@ -1085,7 +1085,7 @@ int main(int argc, char **argv)
 				    " for stdout `%s': %s",
 				    applet, redirect_stdout, strerror(errno));
 		}else if (stdout_process) {
-			stdout_fd = rc_pipe_command(stdout_process, devnull_fd);
+			stdout_fd = rc_pipe_command(stdout_process);
 			if (stdout_fd == -1)
 				eerrorx("%s: unable to open the logging process"
 				    " for stdout `%s': %s",
@@ -1099,7 +1099,7 @@ int main(int argc, char **argv)
 				    " for stderr `%s': %s",
 				    applet, redirect_stderr, strerror(errno));
 		}else if (stderr_process) {
-			stderr_fd = rc_pipe_command(stderr_process, devnull_fd);
+			stderr_fd = rc_pipe_command(stderr_process);
 			if (stderr_fd == -1)
 				eerrorx("%s: unable to open the logging process"
 				    " for stderr `%s': %s",