From: Petr Štetiar <ynezz@true.cz>
Date: Fri, 17 Jan 2020 15:21:51 +0000 (+0100)
Subject: instance: provide error feedback if ujail binary is missing
X-Git-Url: http://git.openwrt.org/?p=project%2Fprocd.git;a=commitdiff_plain;h=557f11b3a20f2cf6897aad067ffde9d92e9fe015

instance: provide error feedback if ujail binary is missing

Otherwise it's quite hard to track such issues.  While at it, be DRY and
use UJAIL_BIN_PATH constant for ujail binary.

Signed-off-by: Petr Štetiar <ynezz@true.cz>
---

diff --git a/service/instance.c b/service/instance.c
index 14da862..e5615d5 100644
--- a/service/instance.c
+++ b/service/instance.c
@@ -36,6 +36,7 @@
 #include "service.h"
 #include "instance.h"
 
+#define UJAIL_BIN_PATH "/sbin/ujail"
 
 enum {
 	INSTANCE_ATTR_COMMAND,
@@ -205,7 +206,7 @@ jail_run(struct service_instance *in, char **argv)
 	struct jail *jail = &in->jail;
 	int argc = 0;
 
-	argv[argc++] = "/sbin/ujail";
+	argv[argc++] = UJAIL_BIN_PATH;
 
 	if (jail->name) {
 		argv[argc++] = "-n";
@@ -795,9 +796,13 @@ instance_jail_parse(struct service_instance *in, struct blob_attr *attr)
 	struct blob_attr *tb[__JAIL_ATTR_MAX];
 	struct jail *jail = &in->jail;
 	struct stat s;
+	int r;
 
-	if (stat("/sbin/ujail", &s))
+	r = stat(UJAIL_BIN_PATH, &s);
+	if (r < 0) {
+		ERROR("unable to find %s: %m (%d)\n", UJAIL_BIN_PATH, r);
 		return 0;
+	}
 
 	blobmsg_parse(jail_attr, __JAIL_ATTR_MAX, tb,
 		blobmsg_data(attr), blobmsg_data_len(attr));