From: David Härdeman <david@hardeman.nu>
Date: Fri, 17 Oct 2025 11:54:50 +0000 (+0200)
Subject: dhcvp4: use tmp fd in dhcpv4_setup_interface()
X-Git-Url: http://git.openwrt.org/?a=commitdiff_plain;h=24f0135006910abf619831b2b7a881895e6d15ff;p=project%2Fodhcpd.git

dhcvp4: use tmp fd in dhcpv4_setup_interface()

This makes the code a little bit easier to read.

Signed-off-by: David Härdeman <david@hardeman.nu>
Link: https://github.com/openwrt/odhcpd/pull/318
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
---

diff --git a/src/dhcpv4.c b/src/dhcpv4.c
index 3f41188..c31d521 100644
--- a/src/dhcpv4.c
+++ b/src/dhcpv4.c
@@ -1444,6 +1444,7 @@ int dhcpv4_setup_interface(struct interface *iface, bool enable)
 		.sin_addr = { INADDR_ANY },
 	};
 	int val = 1;
+	int fd;
 
 	if (iface->dhcpv4_event.uloop.fd >= 0) {
 		uloop_fd_delete(&iface->dhcpv4_event.uloop);
@@ -1459,60 +1460,54 @@ int dhcpv4_setup_interface(struct interface *iface, bool enable)
 		return 0;
 	}
 
-	iface->dhcpv4_event.uloop.fd = socket(AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP);
-	if (iface->dhcpv4_event.uloop.fd < 0) {
+	fd = socket(AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP);
+	if (fd < 0) {
 		error("socket(AF_INET): %m");
 		ret = -1;
 		goto out;
 	}
 
 	/* Basic IPv4 configuration */
-	if (setsockopt(iface->dhcpv4_event.uloop.fd, SOL_SOCKET, SO_REUSEADDR,
-		       &val, sizeof(val)) < 0) {
+	if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val)) < 0) {
 		error("setsockopt(SO_REUSEADDR): %m");
 		ret = -1;
 		goto out;
 	}
 
-	if (setsockopt(iface->dhcpv4_event.uloop.fd, SOL_SOCKET, SO_BROADCAST,
-		       &val, sizeof(val)) < 0) {
+	if (setsockopt(fd, SOL_SOCKET, SO_BROADCAST, &val, sizeof(val)) < 0) {
 		error("setsockopt(SO_BROADCAST): %m");
 		ret = -1;
 		goto out;
 	}
 
-	if (setsockopt(iface->dhcpv4_event.uloop.fd, IPPROTO_IP, IP_PKTINFO,
-		       &val, sizeof(val)) < 0) {
+	if (setsockopt(fd, IPPROTO_IP, IP_PKTINFO, &val, sizeof(val)) < 0) {
 		error("setsockopt(IP_PKTINFO): %m");
 		ret = -1;
 		goto out;
 	}
 
 	val = IPTOS_CLASS_CS6;
-	if (setsockopt(iface->dhcpv4_event.uloop.fd, IPPROTO_IP, IP_TOS, &val,
-		       sizeof(val)) < 0) {
+	if (setsockopt(fd, IPPROTO_IP, IP_TOS, &val, sizeof(val)) < 0) {
 		error("setsockopt(IP_TOS): %m");
 		ret = -1;
 		goto out;
 	}
 
 	val = IP_PMTUDISC_DONT;
-	if (setsockopt(iface->dhcpv4_event.uloop.fd, IPPROTO_IP, IP_MTU_DISCOVER,
-		       &val, sizeof(val)) < 0) {
+	if (setsockopt(fd, IPPROTO_IP, IP_MTU_DISCOVER, &val, sizeof(val)) < 0) {
 		error("setsockopt(IP_MTU_DISCOVER): %m");
 		ret = -1;
 		goto out;
 	}
 
-	if (setsockopt(iface->dhcpv4_event.uloop.fd, SOL_SOCKET, SO_BINDTODEVICE,
-		       iface->ifname, strlen(iface->ifname)) < 0) {
+	if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, iface->ifname,
+		       strlen(iface->ifname)) < 0) {
 		error("setsockopt(SO_BINDTODEVICE): %m");
 		ret = -1;
 		goto out;
 	}
 
-	if (bind(iface->dhcpv4_event.uloop.fd, (struct sockaddr *)&bind_addr,
-		 sizeof(bind_addr)) < 0) {
+	if (bind(fd, (struct sockaddr *)&bind_addr, sizeof(bind_addr)) < 0) {
 		error("bind(): %m");
 		ret = -1;
 		goto out;
@@ -1523,15 +1518,13 @@ int dhcpv4_setup_interface(struct interface *iface, bool enable)
 		goto out;
 	}
 
+	iface->dhcpv4_event.uloop.fd = fd;
 	iface->dhcpv4_event.handle_dgram = dhcpv4_handle_dgram;
 	odhcpd_register(&iface->dhcpv4_event);
+	return 0;
 
 out:
-	if (ret < 0 && iface->dhcpv4_event.uloop.fd >= 0) {
-		close(iface->dhcpv4_event.uloop.fd);
-		iface->dhcpv4_event.uloop.fd = -1;
-	}
-
+	close(fd);
 	return ret;
 }