Added methods to create and read from file-backed metafiles to the Windows Emf class.

BUG=None
TEST=Unittests

Review URL: http://codereview.chromium.org/3538003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@60994 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 35 insertions, 2 deletions

diff --git a/printing/emf_win_unittest.cc b/printing/emf_win_unittest.cc
index 3b4c473..4c1247b 100644
--- a/printing/emf_win_unittest.cc
+++ b/printing/emf_win_unittest.cc
@@ -33,11 +33,11 @@ class EmfPrintingTest : public testing::Test {
   }
 };
 
+const uint32 EMF_HEADER_SIZE = 128;
+
 }  // namespace
 
 TEST(EmfTest, DC) {
-  static const uint32 EMF_HEADER_SIZE = 128;
-
   // Simplest use case.
   printing::Emf emf;
   RECT rect = {100, 100, 200, 200};
@@ -154,3 +154,36 @@ TEST_F(EmfPrintingTest, PageBreak) {
   }
 }
 
+TEST(EmfTest, FileBackedDC) {
+  // Simplest use case.
+  printing::Emf emf;
+  RECT rect = {100, 100, 200, 200};
+  HDC hdc = CreateCompatibleDC(NULL);
+  EXPECT_TRUE(hdc != NULL);
+  FilePath metafile_path;
+  EXPECT_TRUE(file_util::CreateTemporaryFile(&metafile_path));
+  EXPECT_TRUE(emf.CreateFileBackedDc(hdc, &rect, metafile_path));
+  EXPECT_TRUE(emf.hdc() != NULL);
+  // In theory, you'd use the HDC with GDI functions here.
+  EXPECT_TRUE(emf.CloseDc());
+
+  uint32 size = emf.GetDataSize();
+  EXPECT_EQ(size, EMF_HEADER_SIZE);
+  std::vector<BYTE> data;
+  EXPECT_TRUE(emf.GetData(&data));
+  EXPECT_EQ(data.size(), size);
+  emf.CloseEmf();
+  int64 file_size = 0;
+  file_util::GetFileSize(metafile_path, &file_size);
+  EXPECT_EQ(size, file_size);
+  EXPECT_TRUE(DeleteDC(hdc));
+
+  // Playback the data.
+  hdc = CreateCompatibleDC(NULL);
+  EXPECT_TRUE(hdc);
+  EXPECT_TRUE(emf.CreateFromFile(metafile_path));
+  RECT output_rect = {0, 0, 10, 10};
+  EXPECT_TRUE(emf.Playback(hdc, &output_rect));
+  EXPECT_TRUE(DeleteDC(hdc));
+}
+