From: David Härdeman <david@hardeman.nu>
Date: Sat, 8 Nov 2025 16:48:00 +0000 (+0100)
Subject: statefiles: write straight to file in statefiles_write_state4()
X-Git-Url: http://git.openwrt.org/?a=commitdiff_plain;h=940ecbb3916162cf734ffe95e87363199a0c119b;p=project%2Fodhcpd.git

statefiles: write straight to file in statefiles_write_state4()

Instead of writing to a buffer, then to a file, just write straight to
file. This also makes the order of the steps in the function more
logical (i.e. matches the order in which things are actually written to
file).

Signed-off-by: David Härdeman <david@hardeman.nu>
Link: https://github.com/openwrt/odhcpd/pull/302
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
---

diff --git a/src/statefiles.c b/src/statefiles.c
index c392e34..2c41032 100644
--- a/src/statefiles.c
+++ b/src/statefiles.c
@@ -213,26 +213,25 @@ static void statefiles_write_state4(struct write_ctxt *ctxt, struct dhcpv4_lease
 	struct in_addr addr = { .s_addr = lease->addr };
 	char ipbuf[INET6_ADDRSTRLEN];
 
-	odhcpd_hexlify(hexhwaddr, lease->hwaddr, sizeof(lease->hwaddr));
 	inet_ntop(AF_INET, &addr, ipbuf, sizeof(ipbuf));
 
-	/* # <iface> <hexhwaddr> "ipv4" <hostname> <valid_until> <hexaddr> "32" <addrstr>"/32" */
-	ctxt->buf_idx = snprintf(ctxt->buf, ctxt->buf_len,
-				 "# %s %s ipv4 %s%s %" PRId64 " %x 32 %s/32\n",
-				 ctxt->iface->ifname, hexhwaddr,
-				 (lease->flags & OAF_BROKEN_HOSTNAME) ? "broken\\x20" : "",
-				 (lease->hostname ? lease->hostname : "-"),
-				 (lease->valid_until > ctxt->now ?
-				  (int64_t)(lease->valid_until - ctxt->now + ctxt->wall_time) :
-				  (INFINITE_VALID(lease->valid_until) ? -1 : 0)),
-				 ntohl(lease->addr), ipbuf);
-
 	if (statefiles_write_host4(ctxt, lease)) {
 		md5_hash(ipbuf, strlen(ipbuf), &ctxt->md5);
 		md5_hash(lease->hostname, strlen(lease->hostname), &ctxt->md5);
 	}
 
-	fwrite(ctxt->buf, 1, ctxt->buf_idx, ctxt->fp);
+	odhcpd_hexlify(hexhwaddr, lease->hwaddr, sizeof(lease->hwaddr));
+
+	/* # <iface> <hexhwaddr> "ipv4" <hostname> <valid_until> <hexaddr> "32" <addrstr>"/32" */
+	fprintf(ctxt->fp,
+		"# %s %s ipv4 %s%s %" PRId64 " %x 32 %s/32\n",
+		ctxt->iface->ifname, hexhwaddr,
+		(lease->flags & OAF_BROKEN_HOSTNAME) ? "broken\\x20" : "",
+		(lease->hostname ? lease->hostname : "-"),
+		(lease->valid_until > ctxt->now ?
+		 (int64_t)(lease->valid_until - ctxt->now + ctxt->wall_time) :
+		 (INFINITE_VALID(lease->valid_until) ? -1 : 0)),
+		ntohl(lease->addr), ipbuf);
 }
 
 static bool statefiles_write_state(time_t now)