2 files changed, 98 insertions, 2 deletions

diff --git a/test/core/iomgr/BUILD b/test/core/iomgr/BUILD
index e920ceacf0..5acf269988 100644
--- a/test/core/iomgr/BUILD
+++ b/test/core/iomgr/BUILD
@@ -128,8 +128,25 @@ grpc_cc_test(
 )
 
 grpc_cc_test(
-    name = "resolve_address_posix_test",
+    name = "resolve_address_using_ares_resolver_posix_test",
     srcs = ["resolve_address_posix_test.cc"],
+    args = [
+        "--resolver=ares",
+    ],
+    language = "C++",
+    deps = [
+        "//:gpr",
+        "//:grpc",
+        "//test/core/util:grpc_test_util",
+    ],
+)
+
+grpc_cc_test(
+    name = "resolve_address_using_native_resolver_posix_test",
+    srcs = ["resolve_address_posix_test.cc"],
+    args = [
+        "--resolver=native",
+    ],
     language = "C++",
     deps = [
         "//:gpr",
diff --git a/test/core/iomgr/resolve_address_posix_test.cc b/test/core/iomgr/resolve_address_posix_test.cc
index 5785c73e22..826c7e1faf 100644
--- a/test/core/iomgr/resolve_address_posix_test.cc
+++ b/test/core/iomgr/resolve_address_posix_test.cc
@@ -18,12 +18,14 @@
 
 #include "src/core/lib/iomgr/resolve_address.h"
 
+#include <net/if.h>
 #include <string.h>
 #include <sys/un.h>
 
 #include <grpc/grpc.h>
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
 #include <grpc/support/sync.h>
 #include <grpc/support/time.h>
 
@@ -33,6 +35,7 @@
 #include "src/core/lib/gprpp/thd.h"
 #include "src/core/lib/iomgr/executor.h"
 #include "src/core/lib/iomgr/iomgr.h"
+#include "test/core/util/cmdline.h"
 #include "test/core/util/test_config.h"
 
 static gpr_timespec test_deadline(void) {
@@ -117,12 +120,18 @@ static void must_succeed(void* argsp, grpc_error* err) {
   GPR_ASSERT(args->addrs != nullptr);
   GPR_ASSERT(args->addrs->naddrs > 0);
   gpr_atm_rel_store(&args->done_atm, 1);
+  gpr_mu_lock(args->mu);
+  GRPC_LOG_IF_ERROR("pollset_kick", grpc_pollset_kick(args->pollset, nullptr));
+  gpr_mu_unlock(args->mu);
 }
 
 static void must_fail(void* argsp, grpc_error* err) {
   args_struct* args = static_cast<args_struct*>(argsp);
   GPR_ASSERT(err != GRPC_ERROR_NONE);
   gpr_atm_rel_store(&args->done_atm, 1);
+  gpr_mu_lock(args->mu);
+  GRPC_LOG_IF_ERROR("pollset_kick", grpc_pollset_kick(args->pollset, nullptr));
+  gpr_mu_unlock(args->mu);
 }
 
 static void test_unix_socket(void) {
@@ -159,22 +168,92 @@ static void test_unix_socket_path_name_too_long(void) {
   args_finish(&args);
 }
 
+static void resolve_address_must_succeed(const char* target) {
+  grpc_core::ExecCtx exec_ctx;
+  args_struct args;
+  args_init(&args);
+  poll_pollset_until_request_done(&args);
+  grpc_resolve_address(
+      target, "1" /* port number */, args.pollset_set,
+      GRPC_CLOSURE_CREATE(must_succeed, &args, grpc_schedule_on_exec_ctx),
+      &args.addrs);
+  grpc_core::ExecCtx::Get()->Flush();
+  args_finish(&args);
+}
+
+static void test_named_and_numeric_scope_ids(void) {
+  char* arbitrary_interface_name = static_cast<char*>(gpr_zalloc(IF_NAMESIZE));
+  int interface_index = 0;
+  // Probe candidate interface index numbers until we find one that the
+  // system recognizes, and then use that for the test.
+  for (size_t i = 1; i < 65536; i++) {
+    if (if_indextoname(i, arbitrary_interface_name) != nullptr) {
+      gpr_log(
+          GPR_DEBUG,
+          "Found interface at index %d named %s. Will use this for the test",
+          (int)i, arbitrary_interface_name);
+      interface_index = (int)i;
+      break;
+    }
+  }
+  GPR_ASSERT(strlen(arbitrary_interface_name) > 0);
+  // Test resolution of an ipv6 address with a named scope ID
+  gpr_log(GPR_DEBUG, "test resolution with a named scope ID");
+  char* target_with_named_scope_id = nullptr;
+  gpr_asprintf(&target_with_named_scope_id, "fe80::1234%%%s",
+               arbitrary_interface_name);
+  resolve_address_must_succeed(target_with_named_scope_id);
+  gpr_free(target_with_named_scope_id);
+  gpr_free(arbitrary_interface_name);
+  // Test resolution of an ipv6 address with a numeric scope ID
+  gpr_log(GPR_DEBUG, "test resolution with a numeric scope ID");
+  char* target_with_numeric_scope_id = nullptr;
+  gpr_asprintf(&target_with_numeric_scope_id, "fe80::1234%%%d",
+               interface_index);
+  resolve_address_must_succeed(target_with_numeric_scope_id);
+  gpr_free(target_with_numeric_scope_id);
+}
+
 int main(int argc, char** argv) {
+  // First set the resolver type based off of --resolver
+  const char* resolver_type = nullptr;
+  gpr_cmdline* cl = gpr_cmdline_create("resolve address test");
+  gpr_cmdline_add_string(cl, "resolver", "Resolver type (ares or native)",
+                         &resolver_type);
+  // In case that there are more than one argument on the command line,
+  // --resolver will always be the first one, so only parse the first argument
+  // (other arguments may be unknown to cl)
+  gpr_cmdline_parse(cl, argc > 2 ? 2 : argc, argv);
+  const char* cur_resolver = gpr_getenv("GRPC_DNS_RESOLVER");
+  if (cur_resolver != nullptr && strlen(cur_resolver) != 0) {
+    gpr_log(GPR_INFO, "Warning: overriding resolver setting of %s",
+            cur_resolver);
+  }
+  if (gpr_stricmp(resolver_type, "native") == 0) {
+    gpr_setenv("GRPC_DNS_RESOLVER", "native");
+  } else if (gpr_stricmp(resolver_type, "ares") == 0) {
+    gpr_setenv("GRPC_DNS_RESOLVER", "ares");
+  } else {
+    gpr_log(GPR_ERROR, "--resolver_type was not set to ares or native");
+    abort();
+  }
   grpc::testing::TestEnvironment env(argc, argv);
   grpc_init();
 
   {
     grpc_core::ExecCtx exec_ctx;
-    char* resolver_env = gpr_getenv("GRPC_DNS_RESOLVER");
+    test_named_and_numeric_scope_ids();
     // c-ares resolver doesn't support UDS (ability for native DNS resolver
     // to handle this is only expected to be used by servers, which
     // unconditionally use the native DNS resolver).
+    char* resolver_env = gpr_getenv("GRPC_DNS_RESOLVER");
     if (resolver_env == nullptr || gpr_stricmp(resolver_env, "native") == 0) {
       test_unix_socket();
       test_unix_socket_path_name_too_long();
     }
     gpr_free(resolver_env);
   }
+  gpr_cmdline_destroy(cl);
 
   grpc_shutdown();
   return 0;