1 files changed, 96 insertions, 0 deletions
diff --git a/mojo/common/data_pipe_utils.cc b/mojo/common/data_pipe_utils.cc
new file mode 100644
index 0000000000..9b069b80c5
--- /dev/null
+++ b/mojo/common/data_pipe_utils.cc
@@ -0,0 +1,96 @@
+// 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/data_pipe_utils.h"
+
+#include <utility>
+
+#include "base/bind.h"
+#include "mojo/public/cpp/system/wait.h"
+
+namespace mojo {
+namespace common {
+namespace {
+
+bool BlockingCopyHelper(ScopedDataPipeConsumerHandle source,
+    const base::Callback<size_t(const void*, uint32_t)>& write_bytes) {
+  for (;;) {
+    const void* buffer;
+    uint32_t num_bytes;
+    MojoResult result = BeginReadDataRaw(
+        source.get(), &buffer, &num_bytes, MOJO_READ_DATA_FLAG_NONE);
+    if (result == MOJO_RESULT_OK) {
+      size_t bytes_written = write_bytes.Run(buffer, num_bytes);
+      result = EndReadDataRaw(source.get(), num_bytes);
+      if (bytes_written < num_bytes || result != MOJO_RESULT_OK)
+        return false;
+    } else if (result == MOJO_RESULT_SHOULD_WAIT) {
+      result = Wait(source.get(), MOJO_HANDLE_SIGNAL_READABLE);
+      if (result != MOJO_RESULT_OK) {
+        // If the producer handle was closed, then treat as EOF.
+        return result == MOJO_RESULT_FAILED_PRECONDITION;
+      }
+    } else if (result == MOJO_RESULT_FAILED_PRECONDITION) {
+      // If the producer handle was closed, then treat as EOF.
+      return true;
+    } else {
+      // Some other error occurred.
+      break;
+    }
+  }
+
+  return false;
+}
+
+size_t CopyToStringHelper(
+    std::string* result, const void* buffer, uint32_t num_bytes) {
+  result->append(static_cast<const char*>(buffer), num_bytes);
+  return num_bytes;
+}
+
+}  // namespace
+
+// TODO(hansmuller): Add a max_size parameter.
+bool BlockingCopyToString(ScopedDataPipeConsumerHandle source,
+                          std::string* result) {
+  CHECK(result);
+  result->clear();
+  return BlockingCopyHelper(std::move(source),
+                            base::Bind(&CopyToStringHelper, result));
+}
+
+bool MOJO_COMMON_EXPORT BlockingCopyFromString(
+    const std::string& source,
+    const ScopedDataPipeProducerHandle& destination) {
+  auto it = source.begin();
+  for (;;) {
+    void* buffer = nullptr;
+    uint32_t buffer_num_bytes = 0;
+    MojoResult result =
+        BeginWriteDataRaw(destination.get(), &buffer, &buffer_num_bytes,
+                          MOJO_WRITE_DATA_FLAG_NONE);
+    if (result == MOJO_RESULT_OK) {
+      char* char_buffer = static_cast<char*>(buffer);
+      uint32_t byte_index = 0;
+      while (it != source.end() && byte_index < buffer_num_bytes) {
+        char_buffer[byte_index++] = *it++;
+      }
+      EndWriteDataRaw(destination.get(), byte_index);
+      if (it == source.end())
+        return true;
+    } else if (result == MOJO_RESULT_SHOULD_WAIT) {
+      result = Wait(destination.get(), MOJO_HANDLE_SIGNAL_WRITABLE);
+      if (result != MOJO_RESULT_OK) {
+        // If the consumer handle was closed, then treat as EOF.
+        return result == MOJO_RESULT_FAILED_PRECONDITION;
+      }
+    } else {
+      // If the consumer handle was closed, then treat as EOF.
+      return result == MOJO_RESULT_FAILED_PRECONDITION;
+    }
+  }
+}
+
+}  // namespace common
+}  // namespace mojo