service: return the svc from service_register()

Settings that exist only in the block format have nowhere to go: the
legacy line cannot carry them, and service_register() returned an errno
that no caller ever read, so conf.c had no handle on the service it just
created.  Return the svc instead, NULL with errno set on failure, errno
zero when a block is skipped on purpose.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

src/service.c

@@ -1875,9 +1875,11 @@ static void parse_cmdline_args(svc_t *svc, char *cmd, char **args)
  * defaults to "" (empty string).
  *
  * Returns:
- * POSIX OK(0) on success, or non-zero errno exit status on failure.
+ * The registered svc, or %NULL with @errno set on failure.  A block
+ * skipped on purpose -- conditional loading, bootstrap over, nowarn --
+ * also returns %NULL, with @errno zero.
  */
-int service_register(int type, char *cfg, struct rlimit rlimit[], char *file)
+svc_t *service_register(int type, char *cfg, struct rlimit rlimit[], char *file)
 {
 	char *cmd, *desc, *runlevels = NULL, *cond = NULL;
 	char *username = NULL, *log = NULL, *pid = NULL;
@@ -1905,12 +1907,15 @@ int service_register(int type, char *cfg, struct rlimit rlimit[], char *file)
 
 	if (!cfg) {
 		errx(1, "Invalid input argument");
-		return errno = EINVAL;
+		errno = EINVAL;
+		return NULL;
 	}
 
 	line = strdupa(cfg);
-	if (!line)
-		return 1;
+	if (!line) {
+		errno = ENOMEM;
+		return NULL;
+	}
 
 	desc = strstr(line, "-- ");
 	if (desc) {
@@ -1935,7 +1940,8 @@ int service_register(int type, char *cfg, struct rlimit rlimit[], char *file)
 	if (!cmd) {
 	incomplete:
 		errx(1, "Incomplete service '%s', cannot register", cfg);
-		return errno = ENOENT;
+		errno = ENOENT;
+		return NULL;
 	}
 
 	while (cmd) {
@@ -2035,14 +2041,17 @@ int service_register(int type, char *cfg, struct rlimit rlimit[], char *file)
 		strlcat(ident, id, sizeof(ident));
 	}
 
-	if (ifstmt && !svc_ifthen(1, ident, ifstmt, nowarn))
-		return 0;
+	if (ifstmt && !svc_ifthen(1, ident, ifstmt, nowarn)) {
+		errno = 0;
+		return NULL;
+	}
 
 	levels = conf_parse_runlevels(runlevels);
 	if (runlevel != INIT_LEVEL && !ISOTHER(levels, INIT_LEVEL)) {
 		dbg("Skipping %s%s%s, bootstrap is completed.",
 		    name, id[0] ? ":" : "", id[0] ? id : "");
-		return 0;
+		errno = 0;
+		return NULL;
 	}
 
 	if (type == SVC_TYPE_TTY) {
@@ -2050,7 +2059,7 @@ int service_register(int type, char *cfg, struct rlimit rlimit[], char *file)
 		char *ptr;
 
 		if (tty_parse_args(&tty, cmd, &args))
-			return errno;
+			return NULL;
 
 		/* NOTE: this may result in dev == NULL! */
 		if (tty_isatcon(tty.dev))
@@ -2069,7 +2078,7 @@ int service_register(int type, char *cfg, struct rlimit rlimit[], char *file)
 
 		line = alloca(len);
 		if (!line)
-			return errno;
+			return NULL;
 
 		snprintf(line, len, "%s", tty.cmd ? tty.cmd : "tty");
 		for (i = 0; i < tty.num; i++) {
@@ -2079,7 +2088,7 @@ int service_register(int type, char *cfg, struct rlimit rlimit[], char *file)
 
 		cmd = strtok_r(line, " \t", &args);
 		if (!cmd)
-			return errno;
+			return NULL;
 
 		/* tty's always respawn, never incr. restart_cnt */
 		respawn = 1;
@@ -2104,11 +2113,13 @@ int service_register(int type, char *cfg, struct rlimit rlimit[], char *file)
 		svc = svc_find(name, id);
 
 	if (!whichp(cmd)) {
-		if (nowarn)
-			return 0;
+		if (nowarn) {
+			errno = 0;
+			return NULL;
+		}
 
 		warn("%s: skipping %s", file ? file : "static", cmd);
-		return errno;
+		return NULL;
 	}
 
 	if (!svc) {
@@ -2116,7 +2127,8 @@ int service_register(int type, char *cfg, struct rlimit rlimit[], char *file)
 		svc = svc_new(cmd, name, id, type);
 		if (!svc) {
 			errx(1, "Out of memory, cannot register service %s", cmd);
-			return errno = ENOMEM;
+			errno = ENOMEM;
+			return NULL;
 		}
 
 		if (manual)
@@ -2375,7 +2387,7 @@ int service_register(int type, char *cfg, struct rlimit rlimit[], char *file)
 		}
 	}
 
-	return 0;
+	return svc;
 }
 
 /*

src/service.h

@@ -27,7 +27,7 @@
 
 #include "svc.h"
 
-int	  service_register	 (int type, char *line, struct rlimit rlimit[], char *file);
+svc_t	 *service_register	 (int type, char *line, struct rlimit rlimit[], char *file);
 void      service_unregister     (svc_t *svc);
 
 void      service_runtask_clean  (void);