Revert "Merge pull request #16158 from apolcyn/revert_windows_breakage"

This reverts commit d9e8f86675cf923714b3ead4b06087e14a88c08c, reversing
changes made to 04847aeb1e62bc528d88fa3c47daa24a4cf629b3.

2 files changed, 123 insertions, 39 deletions

diff --git a/test/cpp/naming/address_sorting_test.cc b/test/cpp/naming/address_sorting_test.cc
index a92e9e3b3e..04c300876c 100644
--- a/test/cpp/naming/address_sorting_test.cc
+++ b/test/cpp/naming/address_sorting_test.cc
@@ -24,10 +24,8 @@
 #include <grpc/support/time.h>
 #include <string.h>
 
-#include <arpa/inet.h>
 #include <gflags/gflags.h>
 #include <gmock/gmock.h>
-#include <sys/socket.h>
 #include <sys/types.h>
 #include <vector>
 
@@ -51,6 +49,11 @@
 #include "test/core/util/port.h"
 #include "test/core/util/test_config.h"
 
+#ifndef GPR_WINDOWS
+#include <arpa/inet.h>
+#include <sys/socket.h>
+#endif
+
 namespace {
 
 struct TestAddress {
@@ -190,10 +193,18 @@ void VerifyLbAddrOutputs(grpc_lb_addresses* lb_addrs,
   grpc_lb_addresses_destroy(lb_addrs);
 }
 
-}  // namespace
+/* We need to run each test case inside of its own
+ * isolated grpc_init/grpc_shutdown pair, so that
+ * the "address sorting source addr factory" can be
+ * restored to its default for each test case. */
+class AddressSortingTest : public ::testing::Test {
+ protected:
+  void SetUp() override { grpc_init(); }
+  void TearDown() override { grpc_shutdown(); }
+};
 
 /* Tests for rule 1 */
-TEST(AddressSortingTest, TestDepriotizesUnreachableAddresses) {
+TEST_F(AddressSortingTest, TestDepriotizesUnreachableAddresses) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(
@@ -212,7 +223,7 @@ TEST(AddressSortingTest, TestDepriotizesUnreachableAddresses) {
                                 });
 }
 
-TEST(AddressSortingTest, TestDepriotizesUnsupportedDomainIpv6) {
+TEST_F(AddressSortingTest, TestDepriotizesUnsupportedDomainIpv6) {
   bool ipv4_supported = true;
   bool ipv6_supported = false;
   OverrideAddressSortingSourceAddrFactory(
@@ -231,7 +242,7 @@ TEST(AddressSortingTest, TestDepriotizesUnsupportedDomainIpv6) {
                                 });
 }
 
-TEST(AddressSortingTest, TestDepriotizesUnsupportedDomainIpv4) {
+TEST_F(AddressSortingTest, TestDepriotizesUnsupportedDomainIpv4) {
   bool ipv4_supported = false;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(
@@ -253,7 +264,7 @@ TEST(AddressSortingTest, TestDepriotizesUnsupportedDomainIpv4) {
 
 /* Tests for rule 2 */
 
-TEST(AddressSortingTest, TestDepriotizesNonMatchingScope) {
+TEST_F(AddressSortingTest, TestDepriotizesNonMatchingScope) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(
@@ -277,7 +288,7 @@ TEST(AddressSortingTest, TestDepriotizesNonMatchingScope) {
 
 /* Tests for rule 5 */
 
-TEST(AddressSortingTest, TestUsesLabelFromDefaultTable) {
+TEST_F(AddressSortingTest, TestUsesLabelFromDefaultTable) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(
@@ -300,7 +311,7 @@ TEST(AddressSortingTest, TestUsesLabelFromDefaultTable) {
 
 /* Flip the input on the test above to reorder the sort function's
  * comparator's inputs. */
-TEST(AddressSortingTest, TestUsesLabelFromDefaultTableInputFlipped) {
+TEST_F(AddressSortingTest, TestUsesLabelFromDefaultTableInputFlipped) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(
@@ -323,8 +334,8 @@ TEST(AddressSortingTest, TestUsesLabelFromDefaultTableInputFlipped) {
 
 /* Tests for rule 6 */
 
-TEST(AddressSortingTest,
-     TestUsesDestinationWithHigherPrecedenceWithAnIpv4Address) {
+TEST_F(AddressSortingTest,
+       TestUsesDestinationWithHigherPrecedenceWithAnIpv4Address) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(
@@ -348,8 +359,8 @@ TEST(AddressSortingTest,
                 });
 }
 
-TEST(AddressSortingTest,
-     TestUsesDestinationWithHigherPrecedenceWithV4CompatAndLocalhostAddress) {
+TEST_F(AddressSortingTest,
+       TestUsesDestinationWithHigherPrecedenceWithV4CompatAndLocalhostAddress) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
 // Handle unique observed behavior of inet_ntop(v4-compatible-address) on OS X.
@@ -377,8 +388,8 @@ TEST(AddressSortingTest,
                                 });
 }
 
-TEST(AddressSortingTest,
-     TestUsesDestinationWithHigherPrecedenceWithCatchAllAndLocalhostAddress) {
+TEST_F(AddressSortingTest,
+       TestUsesDestinationWithHigherPrecedenceWithCatchAllAndLocalhostAddress) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(
@@ -403,8 +414,8 @@ TEST(AddressSortingTest,
       });
 }
 
-TEST(AddressSortingTest,
-     TestUsesDestinationWithHigherPrecedenceWith2000PrefixedAddress) {
+TEST_F(AddressSortingTest,
+       TestUsesDestinationWithHigherPrecedenceWith2000PrefixedAddress) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(
@@ -426,7 +437,7 @@ TEST(AddressSortingTest,
                 });
 }
 
-TEST(
+TEST_F(
     AddressSortingTest,
     TestUsesDestinationWithHigherPrecedenceWith2000PrefixedAddressEnsurePrefixMatchHasNoEffect) {
   bool ipv4_supported = true;
@@ -448,8 +459,8 @@ TEST(
                                 });
 }
 
-TEST(AddressSortingTest,
-     TestUsesDestinationWithHigherPrecedenceWithLinkAndSiteLocalAddresses) {
+TEST_F(AddressSortingTest,
+       TestUsesDestinationWithHigherPrecedenceWithLinkAndSiteLocalAddresses) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(
@@ -469,19 +480,22 @@ TEST(AddressSortingTest,
                                 });
 }
 
-TEST(
+TEST_F(
     AddressSortingTest,
     TestUsesDestinationWithHigherPrecedenceWithCatchAllAndAndV4MappedAddresses) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
+  // Use embedded ipv4 addresses with leading 1's instead of zero's to be
+  // compatible with inet_ntop implementations that can display such
+  // addresses with leading zero's as e.g.: "::ffff:0:2", as on windows.
   OverrideAddressSortingSourceAddrFactory(
       ipv4_supported, ipv6_supported,
       {
-          {"[::ffff:0.0.0.2]:443", {"[::ffff:0.0.0.3]:0", AF_INET6}},
+          {"[::ffff:1.1.1.2]:443", {"[::ffff:1.1.1.3]:0", AF_INET6}},
           {"[1234::2]:443", {"[1234::3]:0", AF_INET6}},
       });
   grpc_lb_addresses* lb_addrs = BuildLbAddrInputs({
-      {"[::ffff:0.0.0.2]:443", AF_INET6},
+      {"[::ffff:1.1.1.2]:443", AF_INET6},
       {"[1234::2]:443", AF_INET6},
   });
   grpc_cares_wrapper_test_only_address_sorting_sort(lb_addrs);
@@ -489,13 +503,13 @@ TEST(
                                     // ::ffff:0:2 should match the v4-mapped
                                     // precedence entry and be deprioritized.
                                     "[1234::2]:443",
-                                    "[::ffff:0.0.0.2]:443",
+                                    "[::ffff:1.1.1.2]:443",
                                 });
 }
 
 /* Tests for rule 8 */
 
-TEST(AddressSortingTest, TestPrefersSmallerScope) {
+TEST_F(AddressSortingTest, TestPrefersSmallerScope) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(
@@ -520,7 +534,7 @@ TEST(AddressSortingTest, TestPrefersSmallerScope) {
 
 /* Tests for rule 9 */
 
-TEST(AddressSortingTest, TestPrefersLongestMatchingSrcDstPrefix) {
+TEST_F(AddressSortingTest, TestPrefersLongestMatchingSrcDstPrefix) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(
@@ -543,8 +557,8 @@ TEST(AddressSortingTest, TestPrefersLongestMatchingSrcDstPrefix) {
                                 });
 }
 
-TEST(AddressSortingTest,
-     TestPrefersLongestMatchingSrcDstPrefixMatchesWholeAddress) {
+TEST_F(AddressSortingTest,
+       TestPrefersLongestMatchingSrcDstPrefixMatchesWholeAddress) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(
@@ -564,7 +578,7 @@ TEST(AddressSortingTest,
                                 });
 }
 
-TEST(AddressSortingTest, TestPrefersLongestPrefixStressInnerBytePrefix) {
+TEST_F(AddressSortingTest, TestPrefersLongestPrefixStressInnerBytePrefix) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(
@@ -584,7 +598,7 @@ TEST(AddressSortingTest, TestPrefersLongestPrefixStressInnerBytePrefix) {
                                 });
 }
 
-TEST(AddressSortingTest, TestPrefersLongestPrefixDiffersOnHighestBitOfByte) {
+TEST_F(AddressSortingTest, TestPrefersLongestPrefixDiffersOnHighestBitOfByte) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(
@@ -604,7 +618,7 @@ TEST(AddressSortingTest, TestPrefersLongestPrefixDiffersOnHighestBitOfByte) {
                                 });
 }
 
-TEST(AddressSortingTest, TestPrefersLongestPrefixDiffersByLastBit) {
+TEST_F(AddressSortingTest, TestPrefersLongestPrefixDiffersByLastBit) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(
@@ -628,7 +642,7 @@ TEST(AddressSortingTest, TestPrefersLongestPrefixDiffersByLastBit) {
 
 /* Tests for rule 10 */
 
-TEST(AddressSortingTest, TestStableSort) {
+TEST_F(AddressSortingTest, TestStableSort) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(
@@ -648,7 +662,7 @@ TEST(AddressSortingTest, TestStableSort) {
                                 });
 }
 
-TEST(AddressSortingTest, TestStableSortFiveElements) {
+TEST_F(AddressSortingTest, TestStableSortFiveElements) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(
@@ -677,7 +691,7 @@ TEST(AddressSortingTest, TestStableSortFiveElements) {
                                 });
 }
 
-TEST(AddressSortingTest, TestStableSortNoSrcAddrsExist) {
+TEST_F(AddressSortingTest, TestStableSortNoSrcAddrsExist) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(ipv4_supported, ipv6_supported, {});
@@ -698,7 +712,7 @@ TEST(AddressSortingTest, TestStableSortNoSrcAddrsExist) {
                                 });
 }
 
-TEST(AddressSortingTest, TestStableSortNoSrcAddrsExistWithIpv4) {
+TEST_F(AddressSortingTest, TestStableSortNoSrcAddrsExistWithIpv4) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
   OverrideAddressSortingSourceAddrFactory(ipv4_supported, ipv6_supported, {});
@@ -713,7 +727,7 @@ TEST(AddressSortingTest, TestStableSortNoSrcAddrsExistWithIpv4) {
                                 });
 }
 
-TEST(AddressSortingTest, TestStableSortV4CompatAndSiteLocalAddresses) {
+TEST_F(AddressSortingTest, TestStableSortV4CompatAndSiteLocalAddresses) {
   bool ipv4_supported = true;
   bool ipv6_supported = true;
 // Handle unique observed behavior of inet_ntop(v4-compatible-address) on OS X.
@@ -744,6 +758,78 @@ TEST(AddressSortingTest, TestStableSortV4CompatAndSiteLocalAddresses) {
                       });
 }
 
+/* TestPrefersIpv6Loopback tests the actual "address probing" code
+ * for the current platform, without any mocks.
+ * This test relies on the assumption that the ipv6 loopback address is
+ * available in the hosts/containers that grpc C/C++ tests run on
+ * (whether ipv4 loopback is available or not, an available ipv6
+ * loopback should be preferred). */
+TEST_F(AddressSortingTest, TestPrefersIpv6Loopback) {
+  grpc_lb_addresses* lb_addrs = BuildLbAddrInputs({
+      {"[::1]:443", AF_INET6},
+      {"127.0.0.1:443", AF_INET},
+  });
+  grpc_cares_wrapper_test_only_address_sorting_sort(lb_addrs);
+  VerifyLbAddrOutputs(lb_addrs, {
+                                    "[::1]:443",
+                                    "127.0.0.1:443",
+                                });
+}
+
+/* Flip the order of the inputs above and expect the same output order
+ * (try to rule out influence of arbitrary qsort ordering) */
+TEST_F(AddressSortingTest, TestPrefersIpv6LoopbackInputsFlipped) {
+  grpc_lb_addresses* lb_addrs = BuildLbAddrInputs({
+      {"127.0.0.1:443", AF_INET},
+      {"[::1]:443", AF_INET6},
+  });
+  grpc_cares_wrapper_test_only_address_sorting_sort(lb_addrs);
+  VerifyLbAddrOutputs(lb_addrs, {
+                                    "[::1]:443",
+                                    "127.0.0.1:443",
+                                });
+}
+
+/* Try to rule out false positives in the above two tests in which
+ * the sorter might think that neither ipv6 or ipv4 loopback is
+ * available, but ipv6 loopback is still preferred only due
+ * to precedance table lookups. */
+TEST_F(AddressSortingTest, TestSorterKnowsIpv6LoopbackIsAvailable) {
+  sockaddr_in6 ipv6_loopback;
+  memset(&ipv6_loopback, 0, sizeof(ipv6_loopback));
+  ipv6_loopback.sin6_family = AF_INET6;
+  ((char*)&ipv6_loopback.sin6_addr)[15] = 1;
+  ipv6_loopback.sin6_port = htons(443);
+  // Set up the source and destination parameters of
+  // address_sorting_get_source_addr
+  address_sorting_address sort_input_dest;
+  memcpy(&sort_input_dest.addr, &ipv6_loopback, sizeof(ipv6_loopback));
+  sort_input_dest.len = sizeof(ipv6_loopback);
+  address_sorting_address source_for_sort_input_dest;
+  memset(&source_for_sort_input_dest, 0, sizeof(source_for_sort_input_dest));
+  // address_sorting_get_source_addr returns true if a source address was found
+  // for the destination address, otherwise false.
+  EXPECT_TRUE(address_sorting_get_source_addr_for_testing(
+      &sort_input_dest, &source_for_sort_input_dest));
+  // Now also check that the source address was filled in correctly.
+  EXPECT_GT(source_for_sort_input_dest.len, 0u);
+  sockaddr_in6* source_addr_output =
+      (sockaddr_in6*)source_for_sort_input_dest.addr;
+  EXPECT_EQ(source_addr_output->sin6_family, AF_INET6);
+  char* buf = static_cast<char*>(gpr_zalloc(100));
+  EXPECT_NE(inet_ntop(AF_INET6, &source_addr_output->sin6_addr, buf, 100),
+            nullptr)
+      << "inet_ntop failed. Errno: " + std::to_string(errno);
+  std::string source_addr_str(buf);
+  gpr_free(buf);
+  // This test
+  // assumes that the source address for any loopback destination is also the
+  // loopback address.
+  EXPECT_EQ(source_addr_str, "::1");
+}
+
+}  // namespace
+
 int main(int argc, char** argv) {
   char* resolver = gpr_getenv("GRPC_DNS_RESOLVER");
   if (resolver == nullptr || strlen(resolver) == 0) {
@@ -754,9 +840,7 @@ int main(int argc, char** argv) {
   gpr_free(resolver);
   grpc_test_init(argc, argv);
   ::testing::InitGoogleTest(&argc, argv);
-  grpc_init();
   auto result = RUN_ALL_TESTS();
-  grpc_shutdown();
   // Test sequential and nested inits and shutdowns.
   grpc_init();
   grpc_init();
diff --git a/test/cpp/naming/gen_build_yaml.py b/test/cpp/naming/gen_build_yaml.py
index baa6512f62..5dad2ea7af 100755
--- a/test/cpp/naming/gen_build_yaml.py
+++ b/test/cpp/naming/gen_build_yaml.py
@@ -110,7 +110,7 @@ def main():
               'gtest': True,
               'run': True,
               'src': ['test/cpp/naming/address_sorting_test.cc'],
-              'platforms': ['linux', 'posix', 'mac'],
+              'platforms': ['linux', 'posix', 'mac', 'windows'],
               'deps': [
                   'grpc++_test_util' + unsecure_build_config_suffix,
                   'grpc_test_util' + unsecure_build_config_suffix,