hare

commit 25dc61582fee9d8c225f2058228805929c26cc03
parent 31a916a6dd69bd47821a2f05a2aa52e7eb2cdf51
Author: Drew DeVault <sir@cmpwn.com>
Date:   Mon, 21 Jun 2021 12:02:19 -0400

unix::resolvconf: cache return value

Signed-off-by: Drew DeVault <sir@cmpwn.com>

Diffstat:
M
net/dns/query.ha
 | 
11
+----------
M
unix/resolvconf/load.ha
 | 
14
+++++++++++---

2 files changed, 12 insertions(+), 13 deletions(-)
diff --git a/net/dns/query.ha b/net/dns/query.ha
@@ -2,21 +2,12 @@ use net::ip;
 use net::udp;
 use unix::resolvconf;
 
-let defaults: []ip::addr = [];
-
-@fini fn fini() void = {
-	free(defaults);
-};
-
 // Performs a DNS query using the provided list of DNS servers. The caller must
 // free the return value with [[message_free]]. If no DNS servers are provided,
 // the system defaults (if any) are used.
 export fn query(query: *message, addr: ip::addr...) (*message | error) = {
 	if (len(addr) == 0) {
-		if (len(defaults) == 0) {
-			defaults = resolvconf::load();
-		};
-		addr = defaults;
+		addr = resolvconf::load();
 	};
 
 	let socket = udp::listen(ip::ANY_V4, 0)?;
diff --git a/unix/resolvconf/load.ha b/unix/resolvconf/load.ha
@@ -7,12 +7,20 @@ use strings;
 // XXX: Different platforms may want to configure a different path
 def path: str = "/etc/resolv.conf";
 
+let cache: []ip::addr = [];
+
+@fini fn fini() void = {
+	free(cache);
+};
+
 // Reads a list of nameservers from resolv.conf. Aborts the program if the file
 // does not exist, is written in an invalid format, or if any other error
 // occurs.
 export fn load() []ip::addr = {
 	// XXX: Would be cool if we could do this without allocating anything
-	let servers: []ip::addr = [];
+	if (len(cache) != 0) {
+		return cache;
+	};
 
 	const file = os::open(path)!;
 	defer io::close(file);
@@ -41,8 +49,8 @@ export fn load() []ip::addr = {
 			tok: []u8 => tok,
 		};
 		defer free(tok);
-		append(servers, ip::parse(strings::fromutf8(tok))!);
+		append(cache, ip::parse(strings::fromutf8(tok))!);
 	};
 
-	return servers;
+	return cache;
 };