Create platform_util for tests.

PiperOrigin-RevId: 291869423

5 files changed, 129 insertions, 29 deletions

diff --git a/test/util/BUILD b/test/util/BUILD
index 3c732be62..1ac8b3fd6 100644
--- a/test/util/BUILD
+++ b/test/util/BUILD
@@ -166,6 +166,14 @@ cc_library(
 )
 
 cc_library(
+    name = "platform_util",
+    testonly = 1,
+    srcs = ["platform_util.cc"],
+    hdrs = ["platform_util.h"],
+    deps = [":test_util"],
+)
+
+cc_library(
     name = "posix_error",
     testonly = 1,
     srcs = ["posix_error.cc"],
@@ -238,12 +246,7 @@ cc_library(
         "test_util_runfiles.cc",
     ],
     hdrs = ["test_util.h"],
-    defines = select_system(
-        fuchsia = [
-            "__opensource__",
-            "__fuchsia__",
-        ],
-    ),
+    defines = select_system(),
     deps = [
         ":fs_util",
         ":logging",
diff --git a/test/util/platform_util.cc b/test/util/platform_util.cc
new file mode 100644
index 000000000..2724e63f3
--- /dev/null
+++ b/test/util/platform_util.cc
@@ -0,0 +1,49 @@
+// Copyright 2020 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "test/util/platform_util.h"
+
+#include "test/util/test_util.h"
+
+namespace gvisor {
+namespace testing {
+
+PlatformSupport PlatformSupport32Bit() {
+  if (GvisorPlatform() == Platform::kPtrace) {
+    return PlatformSupport::NotSupported;
+  } else if (GvisorPlatform() == Platform::kKVM) {
+    return PlatformSupport::Segfault;
+  } else {
+    return PlatformSupport::Allowed;
+  }
+}
+
+PlatformSupport PlatformSupportAlignmentCheck() {
+  return PlatformSupport::Allowed;
+}
+
+PlatformSupport PlatformSupportMultiProcess() {
+  return PlatformSupport::Allowed;
+}
+
+PlatformSupport PlatformSupportInt3() {
+  if (GvisorPlatform() == Platform::kKVM) {
+    return PlatformSupport::NotSupported;
+  } else {
+    return PlatformSupport::Allowed;
+  }
+}
+
+}  // namespace testing
+}  // namespace gvisor
diff --git a/test/util/platform_util.h b/test/util/platform_util.h
new file mode 100644
index 000000000..28cc92371
--- /dev/null
+++ b/test/util/platform_util.h
@@ -0,0 +1,56 @@
+// Copyright 2020 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef GVISOR_TEST_UTIL_PLATFORM_UTIL_H_
+#define GVISOR_TEST_UTIL_PLATFORM_UTIL_H_
+
+namespace gvisor {
+namespace testing {
+
+// PlatformSupport is a generic enumeration of classes of support.
+//
+// It is up to the individual functions and callers to agree on the precise
+// definition for each case. The document here generally refers to 32-bit
+// as an example. Many cases will use only NotSupported and Allowed.
+enum class PlatformSupport {
+  // The feature is not supported on the current platform.
+  //
+  // In the case of 32-bit, this means that calls will generally be interpreted
+  // as 64-bit calls, and there is no support for 32-bit binaries, long calls,
+  // etc. This usually means that the underlying implementation just pretends
+  // that 32-bit doesn't exist.
+  NotSupported,
+
+  // Calls will be ignored by the kernel with a fixed error.
+  Ignored,
+
+  // Calls will result in a SIGSEGV or similar fault.
+  Segfault,
+
+  // The feature is supported as expected.
+  //
+  // In the case of 32-bit, this means that the system call or far call will be
+  // handled properly.
+  Allowed,
+};
+
+PlatformSupport PlatformSupport32Bit();
+PlatformSupport PlatformSupportAlignmentCheck();
+PlatformSupport PlatformSupportMultiProcess();
+PlatformSupport PlatformSupportInt3();
+
+}  // namespace testing
+}  // namespace gvisor
+
+#endif  // GVISOR_TEST_UTIL_PLATFORM_UTL_H_
diff --git a/test/util/test_util.cc b/test/util/test_util.cc
index 848504c88..15cbc6da6 100644
--- a/test/util/test_util.cc
+++ b/test/util/test_util.cc
@@ -45,20 +45,13 @@ namespace testing {
 
 bool IsRunningOnGvisor() { return GvisorPlatform() != Platform::kNative; }
 
-Platform GvisorPlatform() {
+const std::string GvisorPlatform() {
   // Set by runner.go.
   char* env = getenv(TEST_ON_GVISOR);
   if (!env) {
     return Platform::kNative;
   }
-  if (strcmp(env, "ptrace") == 0) {
-    return Platform::kPtrace;
-  }
-  if (strcmp(env, "kvm") == 0) {
-    return Platform::kKVM;
-  }
-  std::cerr << "unknown platform " << env;
-  abort();
+  return std::string(env);
 }
 
 bool IsRunningWithHostinet() {
diff --git a/test/util/test_util.h b/test/util/test_util.h
index b3235c7e3..2d22b0eb8 100644
--- a/test/util/test_util.h
+++ b/test/util/test_util.h
@@ -26,16 +26,13 @@
 // IsRunningOnGvisor returns true if the test is known to be running on gVisor.
 // GvisorPlatform can be used to get more detail:
 //
-//   switch (GvisorPlatform()) {
-//     case Platform::kNative:
-//     case Platform::kGvisor:
-//       EXPECT_THAT(mmap(...), SyscallSucceeds());
-//       break;
-//     case Platform::kPtrace:
-//       EXPECT_THAT(mmap(...), SyscallFailsWithErrno(ENOSYS));
-//       break;
+//   if (GvisorPlatform() == Platform::kPtrace) {
+//       ...
 //   }
 //
+// SetupGvisorDeathTest ensures that signal handling does not interfere with
+/// tests that rely on fatal signals.
+//
 // Matchers
 // ========
 //
@@ -213,13 +210,15 @@ void TestInit(int* argc, char*** argv);
     if (expr) GTEST_SKIP() << #expr; \
   } while (0)
 
-enum class Platform {
-  kNative,
-  kKVM,
-  kPtrace,
-};
+// Platform contains platform names.
+namespace Platform {
+constexpr char kNative[] = "native";
+constexpr char kPtrace[] = "ptrace";
+constexpr char kKVM[] = "kvm";
+}  // namespace Platform
+
 bool IsRunningOnGvisor();
-Platform GvisorPlatform();
+const std::string GvisorPlatform();
 bool IsRunningWithHostinet();
 
 #ifdef __linux__