Add constructor to net::FileStream to create it with a base::PlatformFile handle.

Constructor added to both _win and _posix implementations and provided a unit test.

Review URL: http://codereview.chromium.org/20137

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@9428 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 63 insertions, 0 deletions

diff --git a/net/base/file_stream.h b/net/base/file_stream.h
index 67f93ed..20466b4 100644
--- a/net/base/file_stream.h
+++ b/net/base/file_stream.h
@@ -27,6 +27,13 @@ enum Whence {
 class FileStream {
  public:
   FileStream();
+
+  // Construct a FileStream with an existing file handle and opening flags.
+  // |file| is valid file handle.
+  // |flags| is a bitfield of base::PlatformFileFlags when the file handle was
+  // opened.
+  FileStream(base::PlatformFile file, int flags);
+
   ~FileStream();
 
   // Call this method to close the FileStream.  It is OK to call Close
diff --git a/net/base/file_stream_posix.cc b/net/base/file_stream_posix.cc
index abef9c2..7b248a4 100644
--- a/net/base/file_stream_posix.cc
+++ b/net/base/file_stream_posix.cc
@@ -47,6 +47,12 @@ FileStream::FileStream() : file_(base::kInvalidPlatformFileValue) {
   DCHECK(!IsOpen());
 }
 
+FileStream::FileStream(base::PlatformFile file, int flags)
+    : file_(file), open_flags_(flags) {
+  // TODO(hclam): initialize the aync_context_ if the file handle
+  // is opened as an asynchronous file handle.
+}
+
 FileStream::~FileStream() {
   Close();
 }
diff --git a/net/base/file_stream_unittest.cc b/net/base/file_stream_unittest.cc
index abee897..f96d57f 100644
--- a/net/base/file_stream_unittest.cc
+++ b/net/base/file_stream_unittest.cc
@@ -4,6 +4,7 @@
 
 #include "base/file_util.h"
 #include "base/path_service.h"
+#include "base/platform_file.h"
 #include "net/base/file_stream.h"
 #include "net/base/net_errors.h"
 #include "net/base/test_completion_callback.h"
@@ -39,6 +40,44 @@ TEST_F(FileStreamTest, BasicOpenClose) {
   EXPECT_EQ(net::OK, rv);
 }
 
+// Test the use of FileStream with a file handle provided at construction.
+TEST_F(FileStreamTest, UseFileHandle) {
+  bool created = false;
+
+  // 1. Test reading with a file handle.
+  ASSERT_EQ(kTestDataSize,
+      file_util::WriteFile(temp_file_path(), kTestData, kTestDataSize));
+  int flags = base::PLATFORM_FILE_OPEN_ALWAYS | base::PLATFORM_FILE_READ;
+  base::PlatformFile file = base::CreatePlatformFile(
+      temp_file_path().ToWStringHack(), flags, &created);
+
+  // Seek to the beginning of the file and read.
+  net::FileStream read_stream(file, flags);
+  ASSERT_EQ(0, read_stream.Seek(net::FROM_BEGIN, 0));
+  ASSERT_EQ(kTestDataSize, read_stream.Available());
+  // Read into buffer and compare.
+  char buffer[kTestDataSize];
+  ASSERT_EQ(kTestDataSize, read_stream.Read(buffer, kTestDataSize, NULL));
+  ASSERT_EQ(0, memcmp(kTestData, buffer, kTestDataSize));
+  read_stream.Close();
+
+  // 2. Test writing with a file handle.
+  file_util::Delete(temp_file_path(), false);
+  flags = base::PLATFORM_FILE_OPEN_ALWAYS | base::PLATFORM_FILE_WRITE;
+  file = base::CreatePlatformFile(temp_file_path().ToWStringHack(),
+                                  flags, &created);
+
+  net::FileStream write_stream(file, flags);
+  ASSERT_EQ(0, write_stream.Seek(net::FROM_BEGIN, 0));
+  ASSERT_EQ(kTestDataSize, write_stream.Write(kTestData, kTestDataSize, NULL));
+  write_stream.Close();
+
+  // Read into buffer and compare to make sure the handle worked fine.
+  ASSERT_EQ(kTestDataSize,
+      file_util::ReadFile(temp_file_path(), buffer, kTestDataSize));
+  ASSERT_EQ(0, memcmp(kTestData, buffer, kTestDataSize));
+}
+
 TEST_F(FileStreamTest, UseClosedStream) {
   net::FileStream stream;
 
diff --git a/net/base/file_stream_win.cc b/net/base/file_stream_win.cc
index d70b398..ca492a2 100644
--- a/net/base/file_stream_win.cc
+++ b/net/base/file_stream_win.cc
@@ -110,6 +110,17 @@ void FileStream::AsyncContext::OnIOCompleted(
 FileStream::FileStream() : file_(INVALID_HANDLE_VALUE) {
 }
 
+FileStream::FileStream(base::PlatformFile file, int flags)
+    : file_(file), open_flags_(flags) {
+  // If the file handle is opened with base::PLATFORM_FILE_ASYNC, we need to
+  // make sure we will perform asynchronous File IO to it.
+  if (flags & base::PLATFORM_FILE_ASYNC) {
+    async_context_.reset(new AsyncContext(this));
+    MessageLoopForIO::current()->RegisterIOHandler(file_,
+                                                   async_context_.get());
+  }
+}
+
 FileStream::~FileStream() {
   Close();
 }