Write marked content operators when generating a stream.

The marked content operators are BMC, BDC and EMC. In the case of
BDC, it is preceded by a direct dict or a property name.

Bug: pdfium:1118
Change-Id: I3ee736ff7be3e7d7dde55ef581af3444a325e887
Reviewed-on: https://pdfium-review.googlesource.com/37470
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>

1 files changed, 26 insertions, 0 deletions

diff --git a/core/fpdfapi/edit/cpdf_stringarchivestream.h b/core/fpdfapi/edit/cpdf_stringarchivestream.h
new file mode 100644
index 0000000000..bb5481e376
--- /dev/null
+++ b/core/fpdfapi/edit/cpdf_stringarchivestream.h
@@ -0,0 +1,26 @@
+// Copyright 2018 PDFium 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 CORE_FPDFAPI_EDIT_CPDF_STRINGARCHIVESTREAM_H_
+#define CORE_FPDFAPI_EDIT_CPDF_STRINGARCHIVESTREAM_H_
+
+#include "core/fxcrt/fx_stream.h"
+
+class CPDF_StringArchiveStream : public IFX_ArchiveStream {
+ public:
+  explicit CPDF_StringArchiveStream(std::ostringstream* stream);
+  ~CPDF_StringArchiveStream() override;
+
+  // IFX_ArchiveStream
+  bool WriteByte(uint8_t byte) override;
+  bool WriteDWord(uint32_t i) override;
+  FX_FILESIZE CurrentOffset() const override;
+  bool WriteBlock(const void* pData, size_t size) override;
+  bool WriteString(const ByteStringView& str) override;
+
+ private:
+  std::ostringstream* stream_;
+};
+
+#endif  // CORE_FPDFAPI_EDIT_CPDF_STRINGARCHIVESTREAM_H_