Reland: Add some handle read/write helpers to mojo/common/test/test_utils.h

This helps to refactor raw_channel_posix_unittest to run on multiple
platforms.

TEST=mojo_common_unittests,mojo_system_unittests
BUG=None
TBR=viettrungluu@chromium.org

Review URL: https://codereview.chromium.org/176063002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252822 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 211 insertions, 50 deletions

diff --git a/mojo/common/test/multiprocess_test_base_unittest.cc b/mojo/common/test/multiprocess_test_base_unittest.cc
index 7b0a7ff..659b83d 100644
--- a/mojo/common/test/multiprocess_test_base_unittest.cc
+++ b/mojo/common/test/multiprocess_test_base_unittest.cc
@@ -6,22 +6,19 @@
 
 #include "base/logging.h"
 #include "build/build_config.h"
+#include "mojo/common/test/test_utils.h"
 #include "mojo/system/embedder/scoped_platform_handle.h"
 
 #if defined(OS_POSIX)
 #include <fcntl.h>
-#include <unistd.h>
-
-#include "base/posix/eintr_wrapper.h"
 #endif
 
 #if defined(OS_WIN)
-#include <windows.h>
-
 #include "base/win/windows_version.h"
 #endif
 
 namespace mojo {
+namespace test {
 namespace {
 
 // Returns true and logs a warning on Windows prior to Vista.
@@ -46,57 +43,19 @@ bool IsNonBlocking(const embedder::PlatformHandle& handle) {
 #endif
 }
 
-// Note: On POSIX, this method sets the handle to block.
 bool WriteByte(const embedder::PlatformHandle& handle, char c) {
-#if defined(OS_WIN)
-  DWORD num_bytes_written = 0;
-  OVERLAPPED overlapped = { 0 };
-
-  if (!WriteFile(handle.handle, &c, 1, &num_bytes_written, &overlapped)) {
-    if (GetLastError() != ERROR_IO_PENDING)
-      return false;
-
-    if (GetOverlappedResult(handle.handle, &overlapped, &num_bytes_written,
-                            TRUE)) {
-      return num_bytes_written == 1;
-    }
-
-    return false;
-  }
-  return num_bytes_written == 1;
-#else
-  // We're lazy. Set it to block.
-  PCHECK(fcntl(handle.fd, F_SETFL, 0) == 0);
-
-  return HANDLE_EINTR(write(handle.fd, &c, 1)) == 1;
-#endif
+  size_t bytes_written = 0;
+  BlockingWrite(handle, &c, 1, &bytes_written);
+  return bytes_written == 1;
 }
 
-// Note: On POSIX, this method sets the handle to block.
 bool ReadByte(const embedder::PlatformHandle& handle, char* c) {
-#if defined(OS_WIN)
-  DWORD num_bytes_read = 0;
-  OVERLAPPED overlapped = { 0 };
-
-  if (!ReadFile(handle.handle, c, 1, &num_bytes_read, &overlapped)) {
-    if (GetLastError() != ERROR_IO_PENDING)
-      return false;
-
-    if (GetOverlappedResult(handle.handle, &overlapped, &num_bytes_read, TRUE))
-      return num_bytes_read == 1;
-
-    return false;
-  }
-  return num_bytes_read == 1;
-#else
-  // We're lazy. Set it to block.
-  PCHECK(fcntl(handle.fd, F_SETFL, 0) == 0);
-
-  return HANDLE_EINTR(read(handle.fd, c, 1)) == 1;
-#endif
+  size_t bytes_read = 0;
+  BlockingRead(handle, c, 1, &bytes_read);
+  return bytes_read == 1;
 }
 
-typedef test::MultiprocessTestBase MultiprocessTestBaseTest;
+typedef MultiprocessTestBase MultiprocessTestBaseTest;
 
 TEST_F(MultiprocessTestBaseTest, RunChild) {
   if (SkipTest())
@@ -172,4 +131,5 @@ MOJO_MULTIPROCESS_TEST_CHILD_MAIN(PassedChannel) {
 }
 
 }  // namespace
+}  // namespace test
 }  // namespace mojo
diff --git a/mojo/common/test/test_utils.h b/mojo/common/test/test_utils.h
new file mode 100644
index 0000000..369e2bf
--- /dev/null
+++ b/mojo/common/test/test_utils.h
@@ -0,0 +1,44 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef MOJO_COMMON_TEST_TEST_UTILS_H_
+#define MOJO_COMMON_TEST_TEST_UTILS_H_
+
+#include <stddef.h>
+
+namespace mojo {
+
+namespace embedder {
+struct PlatformHandle;
+}
+
+namespace test {
+
+// On success, |bytes_written| is updated to the number of bytes written;
+// otherwise it is untouched.
+bool BlockingWrite(const embedder::PlatformHandle& handle,
+                   const void* buffer,
+                   size_t bytes_to_write,
+                   size_t* bytes_written);
+
+// On success, |bytes_read| is updated to the number of bytes read; otherwise it
+// is untouched.
+bool BlockingRead(const embedder::PlatformHandle& handle,
+                  void* buffer,
+                  size_t buffer_size,
+                  size_t* bytes_read);
+
+// If the read is done successfully or would block, the function returns true
+// and updates |bytes_read| to the number of bytes read (0 if the read would
+// block); otherwise it returns false and leaves |bytes_read| untouched.
+// |handle| must already be in non-blocking mode.
+bool NonBlockingRead(const embedder::PlatformHandle& handle,
+                     void* buffer,
+                     size_t buffer_size,
+                     size_t* bytes_read);
+
+}  // namespace test
+}  // namespace mojo
+
+#endif  // MOJO_COMMON_TEST_TEST_UTILS_H_
diff --git a/mojo/common/test/test_utils_posix.cc b/mojo/common/test/test_utils_posix.cc
new file mode 100644
index 0000000..e4537d3
--- /dev/null
+++ b/mojo/common/test/test_utils_posix.cc
@@ -0,0 +1,77 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "mojo/common/test/test_utils.h"
+
+#include <fcntl.h>
+#include <unistd.h>
+
+#include "base/posix/eintr_wrapper.h"
+#include "mojo/system/embedder/platform_handle.h"
+
+namespace mojo {
+namespace test {
+
+bool BlockingWrite(const embedder::PlatformHandle& handle,
+                   const void* buffer,
+                   size_t bytes_to_write,
+                   size_t* bytes_written) {
+  int original_flags = fcntl(handle.fd, F_GETFL);
+  if (original_flags == -1 ||
+      fcntl(handle.fd, F_SETFL, original_flags & (~O_NONBLOCK)) != 0) {
+    return false;
+  }
+
+  ssize_t result = HANDLE_EINTR(write(handle.fd, buffer, bytes_to_write));
+
+  fcntl(handle.fd, F_SETFL, original_flags);
+
+  if (result < 0)
+    return false;
+
+  *bytes_written = result;
+  return true;
+}
+
+bool BlockingRead(const embedder::PlatformHandle& handle,
+                  void* buffer,
+                  size_t buffer_size,
+                  size_t* bytes_read) {
+  int original_flags = fcntl(handle.fd, F_GETFL);
+  if (original_flags == -1 ||
+      fcntl(handle.fd, F_SETFL, original_flags & (~O_NONBLOCK)) != 0) {
+    return false;
+  }
+
+  ssize_t result = HANDLE_EINTR(read(handle.fd, buffer, buffer_size));
+
+  fcntl(handle.fd, F_SETFL, original_flags);
+
+  if (result < 0)
+    return false;
+
+  *bytes_read = result;
+  return true;
+}
+
+bool NonBlockingRead(const embedder::PlatformHandle& handle,
+                     void* buffer,
+                     size_t buffer_size,
+                     size_t* bytes_read) {
+  ssize_t result = HANDLE_EINTR(read(handle.fd, buffer, buffer_size));
+
+  if (result < 0) {
+    if (errno != EAGAIN && errno != EWOULDBLOCK)
+      return false;
+
+    *bytes_read = 0;
+  } else {
+    *bytes_read = result;
+  }
+
+  return true;
+}
+
+}  // namespace test
+}  // namespace mojo
diff --git a/mojo/common/test/test_utils_win.cc b/mojo/common/test/test_utils_win.cc
new file mode 100644
index 0000000..d4559dc
--- /dev/null
+++ b/mojo/common/test/test_utils_win.cc
@@ -0,0 +1,80 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "mojo/common/test/test_utils.h"
+
+#include <windows.h>
+
+#include "mojo/system/embedder/platform_handle.h"
+
+namespace mojo {
+namespace test {
+
+bool BlockingWrite(const embedder::PlatformHandle& handle,
+                   const void* buffer,
+                   size_t bytes_to_write,
+                   size_t* bytes_written) {
+  OVERLAPPED overlapped = { 0 };
+  DWORD bytes_written_dword = 0;
+
+  if (!WriteFile(handle.handle, buffer, static_cast<DWORD>(bytes_to_write),
+                 &bytes_written_dword, &overlapped)) {
+    if (GetLastError() != ERROR_IO_PENDING ||
+        !GetOverlappedResult(handle.handle, &overlapped, &bytes_written_dword,
+                             TRUE)) {
+      return false;
+    }
+  }
+
+  *bytes_written = bytes_written_dword;
+  return true;
+}
+
+bool BlockingRead(const embedder::PlatformHandle& handle,
+                  void* buffer,
+                  size_t buffer_size,
+                  size_t* bytes_read) {
+  OVERLAPPED overlapped = { 0 };
+  DWORD bytes_read_dword = 0;
+
+  if (!ReadFile(handle.handle, buffer, static_cast<DWORD>(buffer_size),
+                &bytes_read_dword, &overlapped)) {
+    if (GetLastError() != ERROR_IO_PENDING ||
+        !GetOverlappedResult(handle.handle, &overlapped, &bytes_read_dword,
+                             TRUE)) {
+      return false;
+    }
+  }
+
+  *bytes_read = bytes_read_dword;
+  return true;
+}
+
+bool NonBlockingRead(const embedder::PlatformHandle& handle,
+                     void* buffer,
+                     size_t buffer_size,
+                     size_t* bytes_read) {
+  OVERLAPPED overlapped = { 0 };
+  DWORD bytes_read_dword = 0;
+
+  if (!ReadFile(handle.handle, buffer, static_cast<DWORD>(buffer_size),
+                &bytes_read_dword, &overlapped)) {
+    if (GetLastError() != ERROR_IO_PENDING)
+      return false;
+
+    CancelIo(handle.handle);
+
+    if (!GetOverlappedResult(handle.handle, &overlapped, &bytes_read_dword,
+                             TRUE)) {
+      *bytes_read = 0;
+      return true;
+    }
+  }
+
+  *bytes_read = bytes_read_dword;
+  return true;
+}
+
+}  // namespace test
+}  // namespace mojo