test: Check ares_parse_txt_reply_ext() entrypoint

Author: daviddrysdale

test/ares-test-parse-txt.cc

@@ -38,6 +38,40 @@ TEST_F(LibraryTest, ParseTxtReplyOK) {
   ares_free_data(txt);
 }
 
+TEST_F(LibraryTest, ParseTxtExtReplyOK) {
+  DNSPacket pkt;
+  std::string expected1 = "txt1.example.com";
+  std::string expected2a = "txt2a";
+  std::string expected2b("ABC\0ABC", 7);
+  pkt.set_qid(0x1234).set_response().set_aa()
+    .add_question(new DNSQuestion("example.com", ns_t_mx))
+    .add_answer(new DNSTxtRR("example.com", 100, {expected1}))
+    .add_answer(new DNSTxtRR("example.com", 100, {expected2a, expected2b}));
+  std::vector<byte> data = pkt.data();
+
+  struct ares_txt_ext* txt = nullptr;
+  EXPECT_EQ(ARES_SUCCESS, ares_parse_txt_reply_ext(data.data(), data.size(), &txt));
+  ASSERT_NE(nullptr, txt);
+  EXPECT_EQ(std::vector<byte>(expected1.data(), expected1.data() + expected1.size()),
+            std::vector<byte>(txt->txt, txt->txt + txt->length));
+  EXPECT_EQ(1, txt->record_start);
+
+  struct ares_txt_ext* txt2 = txt->next;
+  ASSERT_NE(nullptr, txt2);
+  EXPECT_EQ(std::vector<byte>(expected2a.data(), expected2a.data() + expected2a.size()),
+            std::vector<byte>(txt2->txt, txt2->txt + txt2->length));
+  EXPECT_EQ(1, txt2->record_start);
+
+  struct ares_txt_ext* txt3 = txt2->next;
+  ASSERT_NE(nullptr, txt3);
+  EXPECT_EQ(std::vector<byte>(expected2b.data(), expected2b.data() + expected2b.size()),
+            std::vector<byte>(txt3->txt, txt3->txt + txt3->length));
+  EXPECT_EQ(nullptr, txt3->next);
+  EXPECT_EQ(0, txt3->record_start);
+
+  ares_free_data(txt);
+}
+
 TEST_F(LibraryTest, ParseTxtMalformedReply1) {
   std::vector<byte> data = {
     0x12, 0x34,  // qid