Add a Mojo EDK for Chrome that uses one OS pipe per message pipe.

mojo/edk/system/message_pipe_unittest.cc

Index: mojo/edk/system/message_pipe_unittest.cc
diff --git a/mojo/edk/system/message_pipe_unittest.cc b/mojo/edk/system/message_pipe_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..144f13533e8f1fefb0aa0a049c037c0b5dd7b1b5
--- /dev/null
+++ b/mojo/edk/system/message_pipe_unittest.cc
@@ -0,0 +1,409 @@
+// Copyright 2013 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 "base/memory/ref_counted.h"
+#include "mojo/edk/system/test_utils.h"
+#include "mojo/public/c/system/core.h"
+#include "mojo/public/c/system/types.h"
+
+namespace mojo {
+namespace edk {
+namespace {
+
+const MojoHandleSignals kAllSignals = MOJO_HANDLE_SIGNAL_READABLE |
+                                      MOJO_HANDLE_SIGNAL_WRITABLE |
+                                      MOJO_HANDLE_SIGNAL_PEER_CLOSED;
+static const char kHelloWorld[] = "hello world";
+
+class MessagePipeTest : public test::MojoSystemTest {
+ public:
+  MessagePipeTest() {
+    CHECK_EQ(MOJO_RESULT_OK, MojoCreateMessagePipe(nullptr, &pipe0_, &pipe1_));
+  }
+
+  ~MessagePipeTest() override {
+    if (pipe0_ != MOJO_HANDLE_INVALID)
+      CHECK_EQ(MOJO_RESULT_OK, MojoClose(pipe0_));
+    if (pipe1_ != MOJO_HANDLE_INVALID)
+      CHECK_EQ(MOJO_RESULT_OK, MojoClose(pipe1_));
+  }
+
+  MojoResult WriteMessage(MojoHandle message_pipe_handle,
+                          const void* bytes,
+                          uint32_t num_bytes) {
+    return MojoWriteMessage(message_pipe_handle, bytes, num_bytes, nullptr, 0,
+                            MOJO_WRITE_MESSAGE_FLAG_NONE);
+  }
+
+  MojoResult ReadMessage(MojoHandle message_pipe_handle,
+                         void* bytes,
+                         uint32_t* num_bytes,
+                         bool may_discard = false) {
+    return MojoReadMessage(message_pipe_handle, bytes, num_bytes, nullptr, 0,
+                           may_discard ? MOJO_READ_MESSAGE_FLAG_MAY_DISCARD :
+                                         MOJO_READ_MESSAGE_FLAG_NONE);
+  }
+
+  MojoHandle pipe0_, pipe1_;
+
+ private:
+  MOJO_DISALLOW_COPY_AND_ASSIGN(MessagePipeTest);
+};
+
+TEST_F(MessagePipeTest, WriteData) {
+  ASSERT_EQ(MOJO_RESULT_OK,
+            WriteMessage(pipe0_, kHelloWorld, sizeof(kHelloWorld)));
+}
+
+// Tests:
+//  - only default flags
+//  - reading messages from a port
+//    - when there are no/one/two messages available for that port
+//    - with buffer size 0 (and null buffer) -- should get size
+//    - with too-small buffer -- should get size
+//    - also verify that buffers aren't modified when/where they shouldn't be
+//  - writing messages to a port
+//    - in the obvious scenarios (as above)
+//    - to a port that's been closed
+//  - writing a message to a port, closing the other (would be the source) port,
+//    and reading it
+TEST_F(MessagePipeTest, Basic) {
+  int32_t buffer[2];
+  const uint32_t kBufferSize = static_cast<uint32_t>(sizeof(buffer));
+  uint32_t buffer_size;
+
+  // Nothing to read yet on port 0.
+  buffer[0] = 123;
+  buffer[1] = 456;
+  buffer_size = kBufferSize;
+  ASSERT_EQ(MOJO_RESULT_SHOULD_WAIT, ReadMessage(pipe0_, buffer, &buffer_size));
+  ASSERT_EQ(kBufferSize, buffer_size);
+  ASSERT_EQ(123, buffer[0]);
+  ASSERT_EQ(456, buffer[1]);
+
+  // Ditto for port 1.
+  buffer[0] = 123;
+  buffer[1] = 456;
+  buffer_size = kBufferSize;
+  ASSERT_EQ(MOJO_RESULT_SHOULD_WAIT, ReadMessage(pipe1_, buffer, &buffer_size));
+
+  // Write from port 1 (to port 0).
+  buffer[0] = 789012345;
+  buffer[1] = 0;
+  ASSERT_EQ(MOJO_RESULT_OK, WriteMessage(pipe1_, buffer, sizeof(buffer[0])));
+
+  MojoHandleSignalsState state;
+  ASSERT_EQ(MOJO_RESULT_OK, MojoWait(pipe0_, MOJO_HANDLE_SIGNAL_READABLE,
+                                     MOJO_DEADLINE_INDEFINITE, &state));
+
+  // Read from port 0.
+  buffer[0] = 123;
+  buffer[1] = 456;
+  buffer_size = kBufferSize;
+  ASSERT_EQ(MOJO_RESULT_OK, ReadMessage(pipe0_, buffer, &buffer_size));
+  ASSERT_EQ(static_cast<uint32_t>(sizeof(buffer[0])), buffer_size);
+  ASSERT_EQ(789012345, buffer[0]);
+  ASSERT_EQ(456, buffer[1]);
+
+  // Read again from port 0 -- it should be empty.
+  buffer_size = kBufferSize;
+  ASSERT_EQ(MOJO_RESULT_SHOULD_WAIT, ReadMessage(pipe0_, buffer, &buffer_size));
+
+  // Write two messages from port 0 (to port 1).
+  buffer[0] = 123456789;
+  buffer[1] = 0;
+  ASSERT_EQ(MOJO_RESULT_OK, WriteMessage(pipe0_, buffer, sizeof(buffer[0])));
+  buffer[0] = 234567890;
+  buffer[1] = 0;
+  ASSERT_EQ(MOJO_RESULT_OK, WriteMessage(pipe0_, buffer, sizeof(buffer[0])));
+
+  ASSERT_EQ(MOJO_RESULT_OK, MojoWait(pipe1_, MOJO_HANDLE_SIGNAL_READABLE,
+                                     MOJO_DEADLINE_INDEFINITE, &state));
+
+  // Read from port 1 with buffer size 0 (should get the size of next message).
+  // Also test that giving a null buffer is okay when the buffer size is 0.
+  buffer_size = 0;
+  ASSERT_EQ(MOJO_RESULT_RESOURCE_EXHAUSTED,
+            ReadMessage(pipe1_, nullptr, &buffer_size));
+  ASSERT_EQ(static_cast<uint32_t>(sizeof(buffer[0])), buffer_size);
+
+  // Read from port 1 with buffer size 1 (too small; should get the size of next
+  // message).
+  buffer[0] = 123;
+  buffer[1] = 456;
+  buffer_size = 1;
+  ASSERT_EQ(MOJO_RESULT_RESOURCE_EXHAUSTED,
+            ReadMessage(pipe1_, buffer, &buffer_size));
+  ASSERT_EQ(static_cast<uint32_t>(sizeof(buffer[0])), buffer_size);
+  ASSERT_EQ(123, buffer[0]);
+  ASSERT_EQ(456, buffer[1]);
+
+  // Read from port 1.
+  buffer[0] = 123;
+  buffer[1] = 456;
+  buffer_size = kBufferSize;
+  ASSERT_EQ(MOJO_RESULT_OK, ReadMessage(pipe1_, buffer, &buffer_size));
+  ASSERT_EQ(static_cast<uint32_t>(sizeof(buffer[0])), buffer_size);
+  ASSERT_EQ(123456789, buffer[0]);
+  ASSERT_EQ(456, buffer[1]);
+
+  ASSERT_EQ(MOJO_RESULT_OK, MojoWait(pipe1_, MOJO_HANDLE_SIGNAL_READABLE,
+                                     MOJO_DEADLINE_INDEFINITE, &state));
+
+  // Read again from port 1.
+  buffer[0] = 123;
+  buffer[1] = 456;
+  buffer_size = kBufferSize;
+  ASSERT_EQ(MOJO_RESULT_OK, ReadMessage(pipe1_, buffer, &buffer_size));
+  ASSERT_EQ(static_cast<uint32_t>(sizeof(buffer[0])), buffer_size);
+  ASSERT_EQ(234567890, buffer[0]);
+  ASSERT_EQ(456, buffer[1]);
+
+  // Read again from port 1 -- it should be empty.
+  buffer_size = kBufferSize;
+  ASSERT_EQ(MOJO_RESULT_SHOULD_WAIT, ReadMessage(pipe1_, buffer, &buffer_size));
+
+  // Write from port 0 (to port 1).
+  buffer[0] = 345678901;
+  buffer[1] = 0;
+  ASSERT_EQ(MOJO_RESULT_OK, WriteMessage(pipe0_, buffer, sizeof(buffer[0])));
+
+  // Close port 0.
+  MojoClose(pipe0_);
+  pipe0_ = MOJO_HANDLE_INVALID;
+
+  ASSERT_EQ(MOJO_RESULT_OK, MojoWait(pipe1_, MOJO_HANDLE_SIGNAL_PEER_CLOSED,
+                                     MOJO_DEADLINE_INDEFINITE, &state));
+
+  // Try to write from port 1 (to port 0).
+  buffer[0] = 456789012;
+  buffer[1] = 0;
+  ASSERT_EQ(MOJO_RESULT_FAILED_PRECONDITION,
+            WriteMessage(pipe1_, buffer, sizeof(buffer[0])));
+
+  // Read from port 1; should still get message (even though port 0 was closed).
+  buffer[0] = 123;
+  buffer[1] = 456;
+  buffer_size = kBufferSize;
+  ASSERT_EQ(MOJO_RESULT_OK, ReadMessage(pipe1_, buffer, &buffer_size));
+  ASSERT_EQ(static_cast<uint32_t>(sizeof(buffer[0])), buffer_size);
+  ASSERT_EQ(345678901, buffer[0]);
+  ASSERT_EQ(456, buffer[1]);
+
+  // Read again from port 1 -- it should be empty (and port 0 is closed).
+  buffer_size = kBufferSize;
+  ASSERT_EQ(MOJO_RESULT_FAILED_PRECONDITION,
+            ReadMessage(pipe1_, buffer, &buffer_size));
+}
+
+TEST_F(MessagePipeTest, CloseWithQueuedIncomingMessages) {
+  int32_t buffer[1];
+  const uint32_t kBufferSize = static_cast<uint32_t>(sizeof(buffer));
+  uint32_t buffer_size;
+
+  // Write some messages from port 1 (to port 0).
+  for (int32_t i = 0; i < 5; i++) {
+    buffer[0] = i;
+    ASSERT_EQ(MOJO_RESULT_OK, WriteMessage(pipe1_, buffer, kBufferSize));
+  }
+
+  MojoHandleSignalsState state;
+  ASSERT_EQ(MOJO_RESULT_OK, MojoWait(pipe0_, MOJO_HANDLE_SIGNAL_READABLE,
+                                     MOJO_DEADLINE_INDEFINITE, &state));
+
+  // Port 0 shouldn't be empty.
+  buffer_size = 0;
+  ASSERT_EQ(MOJO_RESULT_RESOURCE_EXHAUSTED,
+            ReadMessage(pipe0_, nullptr, &buffer_size));
+  ASSERT_EQ(kBufferSize, buffer_size);
+
+  // Close port 0 first, which should have outstanding (incoming) messages.
+  MojoClose(pipe0_);
+  MojoClose(pipe1_);
+  pipe0_ = pipe1_ = MOJO_HANDLE_INVALID;
+}
+
+TEST_F(MessagePipeTest, DiscardMode) {
+  int32_t buffer[2];
+  const uint32_t kBufferSize = static_cast<uint32_t>(sizeof(buffer));
+  uint32_t buffer_size;
+
+  // Write from port 1 (to port 0).
+  buffer[0] = 789012345;
+  buffer[1] = 0;
+  ASSERT_EQ(MOJO_RESULT_OK, WriteMessage(pipe1_, buffer, sizeof(buffer[0])));
+
+  MojoHandleSignalsState state;
+  ASSERT_EQ(MOJO_RESULT_OK, MojoWait(pipe0_, MOJO_HANDLE_SIGNAL_READABLE,
+                                     MOJO_DEADLINE_INDEFINITE, &state));
+
+  // Read/discard from port 0 (no buffer); get size.
+  buffer_size = 0;
+  ASSERT_EQ(MOJO_RESULT_RESOURCE_EXHAUSTED,
+            ReadMessage(pipe0_, nullptr, &buffer_size, true));
+  ASSERT_EQ(static_cast<uint32_t>(sizeof(buffer[0])), buffer_size);
+
+  // Read again from port 0 -- it should be empty.
+  buffer_size = kBufferSize;
+  ASSERT_EQ(MOJO_RESULT_SHOULD_WAIT,
+            ReadMessage(pipe0_, buffer, &buffer_size, true));
+
+  // Write from port 1 (to port 0).
+  buffer[0] = 890123456;
+  buffer[1] = 0;
+  ASSERT_EQ(MOJO_RESULT_OK,
+            WriteMessage(pipe1_, buffer, sizeof(buffer[0])));
+
+  ASSERT_EQ(MOJO_RESULT_OK, MojoWait(pipe0_, MOJO_HANDLE_SIGNAL_READABLE,
+                                     MOJO_DEADLINE_INDEFINITE, &state));
+
+  // Read from port 0 (buffer big enough).
+  buffer[0] = 123;
+  buffer[1] = 456;
+  buffer_size = kBufferSize;
+  ASSERT_EQ(MOJO_RESULT_OK, ReadMessage(pipe0_, buffer, &buffer_size, true));
+  ASSERT_EQ(static_cast<uint32_t>(sizeof(buffer[0])), buffer_size);
+  ASSERT_EQ(890123456, buffer[0]);
+  ASSERT_EQ(456, buffer[1]);
+
+  // Read again from port 0 -- it should be empty.
+  buffer_size = kBufferSize;
+  ASSERT_EQ(MOJO_RESULT_SHOULD_WAIT,
+            ReadMessage(pipe0_, buffer, &buffer_size, true));
+
+  // Write from port 1 (to port 0).
+  buffer[0] = 901234567;
+  buffer[1] = 0;
+  ASSERT_EQ(MOJO_RESULT_OK, WriteMessage(pipe1_, buffer, sizeof(buffer[0])));
+
+  ASSERT_EQ(MOJO_RESULT_OK, MojoWait(pipe0_, MOJO_HANDLE_SIGNAL_READABLE,
+                                     MOJO_DEADLINE_INDEFINITE, &state));
+
+  // Read/discard from port 0 (buffer too small); get size.
+  buffer_size = 1;
+  ASSERT_EQ(MOJO_RESULT_RESOURCE_EXHAUSTED,
+            ReadMessage(pipe0_, buffer, &buffer_size, true));
+  ASSERT_EQ(static_cast<uint32_t>(sizeof(buffer[0])), buffer_size);
+
+  // Read again from port 0 -- it should be empty.
+  buffer_size = kBufferSize;
+  ASSERT_EQ(MOJO_RESULT_SHOULD_WAIT,
+            ReadMessage(pipe0_, buffer, &buffer_size, true));
+
+  // Write from port 1 (to port 0).
+  buffer[0] = 123456789;
+  buffer[1] = 0;
+  ASSERT_EQ(MOJO_RESULT_OK, WriteMessage(pipe1_, buffer, sizeof(buffer[0])));
+
+  ASSERT_EQ(MOJO_RESULT_OK, MojoWait(pipe0_, MOJO_HANDLE_SIGNAL_READABLE,
+                                     MOJO_DEADLINE_INDEFINITE, &state));
+
+  // Discard from port 0.
+  buffer_size = 1;
+  ASSERT_EQ(MOJO_RESULT_RESOURCE_EXHAUSTED,
+            ReadMessage(pipe0_, nullptr, 0, true));
+
+  // Read again from port 0 -- it should be empty.
+  buffer_size = kBufferSize;
+  ASSERT_EQ(MOJO_RESULT_SHOULD_WAIT,
+            ReadMessage(pipe0_, buffer, &buffer_size, true));
+}
+
+TEST_F(MessagePipeTest, BasicWaiting) {
+  MojoHandleSignalsState hss;
+
+  int32_t buffer[1];
+  const uint32_t kBufferSize = static_cast<uint32_t>(sizeof(buffer));
+  uint32_t buffer_size;
+
+  // Always writable (until the other port is closed).
+  hss = MojoHandleSignalsState();
+  ASSERT_EQ(MOJO_RESULT_OK, MojoWait(pipe0_, MOJO_HANDLE_SIGNAL_WRITABLE, 0,
+                                     &hss));
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_WRITABLE, hss.satisfied_signals);
+  ASSERT_EQ(kAllSignals, hss.satisfiable_signals);
+  hss = MojoHandleSignalsState();
+
+  // Not yet readable.
+  ASSERT_EQ(MOJO_RESULT_DEADLINE_EXCEEDED,
+            MojoWait(pipe0_, MOJO_HANDLE_SIGNAL_READABLE, 0, &hss));
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_WRITABLE, hss.satisfied_signals);
+  ASSERT_EQ(kAllSignals, hss.satisfiable_signals);
+
+  // The peer is not closed.
+  hss = MojoHandleSignalsState();
+  ASSERT_EQ(MOJO_RESULT_DEADLINE_EXCEEDED,
+            MojoWait(pipe0_, MOJO_HANDLE_SIGNAL_PEER_CLOSED, 0, &hss));
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_WRITABLE, hss.satisfied_signals);
+  ASSERT_EQ(kAllSignals, hss.satisfiable_signals);
+
+  // Write from port 0 (to port 1), to make port 1 readable.
+  buffer[0] = 123456789;
+  ASSERT_EQ(MOJO_RESULT_OK, WriteMessage(pipe0_, buffer, kBufferSize));
+
+  // Port 1 should already be readable now.
+  ASSERT_EQ(MOJO_RESULT_OK, MojoWait(pipe1_, MOJO_HANDLE_SIGNAL_READABLE,
+                                     MOJO_DEADLINE_INDEFINITE, &hss));
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_READABLE | MOJO_HANDLE_SIGNAL_WRITABLE,
+            hss.satisfied_signals);
+  ASSERT_EQ(kAllSignals, hss.satisfiable_signals);
+  // ... and still writable.
+  hss = MojoHandleSignalsState();
+  ASSERT_EQ(MOJO_RESULT_OK, MojoWait(pipe1_, MOJO_HANDLE_SIGNAL_WRITABLE,
+                                     MOJO_DEADLINE_INDEFINITE, &hss));
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_READABLE | MOJO_HANDLE_SIGNAL_WRITABLE,
+            hss.satisfied_signals);
+  ASSERT_EQ(kAllSignals, hss.satisfiable_signals);
+
+  // Close port 0.
+  MojoClose(pipe0_);
+  pipe0_ = MOJO_HANDLE_INVALID;
+
+  // Port 1 should be signaled with peer closed.
+  hss = MojoHandleSignalsState();
+  ASSERT_EQ(MOJO_RESULT_OK, MojoWait(pipe1_, MOJO_HANDLE_SIGNAL_PEER_CLOSED,
+                                     MOJO_DEADLINE_INDEFINITE, &hss));
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_READABLE | MOJO_HANDLE_SIGNAL_PEER_CLOSED,
+            hss.satisfied_signals);
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_READABLE | MOJO_HANDLE_SIGNAL_PEER_CLOSED,
+            hss.satisfiable_signals);
+
+  // Port 1 should not be writable.
+  hss = MojoHandleSignalsState();
+
+  ASSERT_EQ(MOJO_RESULT_FAILED_PRECONDITION,
+            MojoWait(pipe1_, MOJO_HANDLE_SIGNAL_WRITABLE,
+                     MOJO_DEADLINE_INDEFINITE, &hss));
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_READABLE | MOJO_HANDLE_SIGNAL_PEER_CLOSED,
+            hss.satisfied_signals);
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_READABLE | MOJO_HANDLE_SIGNAL_PEER_CLOSED,
+            hss.satisfiable_signals);
+
+  // But it should still be readable.
+  hss = MojoHandleSignalsState();
+  ASSERT_EQ(MOJO_RESULT_OK, MojoWait(pipe1_, MOJO_HANDLE_SIGNAL_READABLE,
+                                     MOJO_DEADLINE_INDEFINITE, &hss));
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_READABLE | MOJO_HANDLE_SIGNAL_PEER_CLOSED,
+            hss.satisfied_signals);
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_READABLE | MOJO_HANDLE_SIGNAL_PEER_CLOSED,
+            hss.satisfiable_signals);
+
+  // Read from port 1.
+  buffer[0] = 0;
+  buffer_size = kBufferSize;
+  ASSERT_EQ(MOJO_RESULT_OK, ReadMessage(pipe1_, buffer, &buffer_size));
+  ASSERT_EQ(123456789, buffer[0]);
+
+  // Now port 1 should no longer be readable.
+  hss = MojoHandleSignalsState();
+  ASSERT_EQ(MOJO_RESULT_FAILED_PRECONDITION,
+            MojoWait(pipe1_, MOJO_HANDLE_SIGNAL_READABLE,
+                     MOJO_DEADLINE_INDEFINITE, &hss));
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_PEER_CLOSED, hss.satisfied_signals);
+  ASSERT_EQ(MOJO_HANDLE_SIGNAL_PEER_CLOSED, hss.satisfiable_signals);
+}
+
+}  // namespace
+}  // namespace edk
+}  // namespace mojo