From 6ecb6c150033a2701c25c5ffb64769190b38c485 Mon Sep 17 00:00:00 2001
From: cpq <valenok@gmail.com>
Date: Thu, 21 Jan 2021 10:00:18 +0000
Subject: [PATCH] Fix DNS timeout, add unit test

---
 examples/http-client/Makefile |  1 +
 mongoose.c                    |  3 ++-
 src/dns.c                     |  3 ++-
 test/unit_test.c              | 23 +++++++++++++++++------
 4 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/examples/http-client/Makefile b/examples/http-client/Makefile
index b41d4be0..aa649765 100644
--- a/examples/http-client/Makefile
+++ b/examples/http-client/Makefile
@@ -1,4 +1,5 @@
 PROG ?= example
+CFLAGS ?= -DMG_ENABLE_LINES $(CFLAGS_EXTRA)
 MBEDTLS_DIR ?=
 
 ifeq "$(MBEDTLS_DIR)" ""
diff --git a/mongoose.c b/mongoose.c
index e305ae28..440feb28 100644
--- a/mongoose.c
+++ b/mongoose.c
@@ -261,7 +261,7 @@ static void dns_cb(struct mg_connection *c, int ev, void *ev_data,
   struct dns_data *d, *tmp;
   if (ev == MG_EV_POLL) {
     unsigned long now = *(unsigned long *) ev_data;
-    for (d = (struct dns_data *) fn_data; d != NULL; d = tmp) {
+    for (d = s_reqs; d != NULL; d = tmp) {
       tmp = d->next;
       // LOG(LL_DEBUG, ("%lu %lu dns poll", d->expire, now));
       if (now > d->expire) mg_error(d->c, "DNS timeout");
@@ -308,6 +308,7 @@ static void dns_cb(struct mg_connection *c, int ev, void *ev_data,
       mg_dns_free(d);
     }
   }
+  (void) fn_data;
 }
 
 void mg_dns_send(struct mg_connection *c, const struct mg_str *name,
diff --git a/src/dns.c b/src/dns.c
index d107ad9d..6220a579 100644
--- a/src/dns.c
+++ b/src/dns.c
@@ -135,7 +135,7 @@ static void dns_cb(struct mg_connection *c, int ev, void *ev_data,
   struct dns_data *d, *tmp;
   if (ev == MG_EV_POLL) {
     unsigned long now = *(unsigned long *) ev_data;
-    for (d = (struct dns_data *) fn_data; d != NULL; d = tmp) {
+    for (d = s_reqs; d != NULL; d = tmp) {
       tmp = d->next;
       // LOG(LL_DEBUG, ("%lu %lu dns poll", d->expire, now));
       if (now > d->expire) mg_error(d->c, "DNS timeout");
@@ -182,6 +182,7 @@ static void dns_cb(struct mg_connection *c, int ev, void *ev_data,
       mg_dns_free(d);
     }
   }
+  (void) fn_data;
 }
 
 void mg_dns_send(struct mg_connection *c, const struct mg_str *name,
diff --git a/test/unit_test.c b/test/unit_test.c
index 6d21fa1c..cee9010a 100644
--- a/test/unit_test.c
+++ b/test/unit_test.c
@@ -1002,6 +1002,11 @@ static void test_str(void) {
   ASSERT(mg_strcmp(mg_str("hi"), mg_strstrip(mg_str(" \thi\r\n"))) == 0);
 }
 
+static void fn1(struct mg_connection *c, int ev, void *ev_data, void *fn_data) {
+  if (ev == MG_EV_ERROR) sprintf((char *) fn_data, "%s", (char *) ev_data);
+  (void) c;
+}
+
 static void test_dns(void) {
   struct mg_dns_message dm;
   //       txid  flags numQ  numA  numAP numOP
@@ -1021,14 +1026,20 @@ static void test_dns(void) {
   ASSERT(mg_dns_parse(data, sizeof(data), &dm) == 1);
   ASSERT(strcmp(dm.name, "") == 0);
 
-#if 0
   {
-    char *data = mg_file_read("dns.bin");
-    ASSERT(data != NULL);
-    ASSERT(mg_dns_parse((uint8_t *) data, mg_file_size("dns.bin"), &dm) == 0);
-    free(data);
+    // Test timeout
+    struct mg_mgr mgr;
+    struct mg_connection *c;
+    char buf[100] = "";
+    int i;
+    mg_mgr_init(&mgr);
+    mgr.dns4.url = "udp://127.0.0.1:12345";
+    mgr.dnstimeout = 10;
+    c = mg_http_connect(&mgr, "http://google.com", fn1, buf);
+    for (i = 0; i < 50 && buf[0] == '\0'; i++) mg_mgr_poll(&mgr, 1);
+    mg_mgr_free(&mgr);
+    ASSERT(strcmp(buf, "DNS timeout") == 0);
   }
-#endif
 }
 
 static void test_util(void) {