am a9c5bb97: Merge "Fix the detection of alt-network in dns resolver."

* commit 'a9c5bb972df7cbb4e65cfb53673b26f9d42deacd':
  Fix the detection of alt-network in dns resolver.

1 files changed, 12 insertions, 9 deletions

diff --git a/libc/netbsd/net/getaddrinfo.c b/libc/netbsd/net/getaddrinfo.c
index 09da66c14..8c1a01b5d 100644
--- a/libc/netbsd/net/getaddrinfo.c
+++ b/libc/netbsd/net/getaddrinfo.c
@@ -93,6 +93,7 @@
 #include <errno.h>
 #include <netdb.h>
 #include "resolv_private.h"
+#include <stdbool.h>
 #include <stddef.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -1864,17 +1865,19 @@ error:
 	free(elems);
 }
 
-static int _using_alt_dns()
+static bool _using_default_dns(const char *iface)
 {
-	char propname[PROP_NAME_MAX];
-	char propvalue[PROP_VALUE_MAX];
+	char buf[IF_NAMESIZE+1];
+	size_t if_len;
 
-	propvalue[0] = 0;
-	snprintf(propname, sizeof(propname), "net.dns1.%d", getpid());
-	if (__system_property_get(propname, propvalue) > 0 ) {
-		return 1;
+	// common case
+	if (iface == NULL || *iface == '\0') return true;
+
+	if_len = _resolv_get_default_iface(buf, sizeof(buf));
+	if (if_len + 1 <= sizeof(buf)) {
+		if (strcmp(buf, iface) != 0) return false;
 	}
-	return 0;
+	return true;
 }
 
 /*ARGSUSED*/
@@ -1926,7 +1929,7 @@ _dns_getaddrinfo(void *rv, void	*cb_data, va_list ap)
 			// Only implement AI_ADDRCONFIG if the application is not
 			// using its own DNS servers, since our implementation
 			// only works on the default connection.
-			if (!_using_alt_dns()) {
+			if (_using_default_dns(iface)) {
 				query_ipv6 = _have_ipv6();
 				query_ipv4 = _have_ipv4();
 			}