Remove MakeSeekableReadStream

This Cl removes the MakeSeekableReadStream call and, at the one place
it's used, creates an IFX_MemoryStream which is a seekable read stream.

Change-Id: I6b0b23636eff47f8caca5432313ba99703e21e4d
Reviewed-on: https://pdfium-review.googlesource.com/4037
Reviewed-by: Nicolás Peña <npm@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>

6 files changed, 93 insertions, 78 deletions

diff --git a/xfa/fxfa/cxfa_ffapp.cpp b/xfa/fxfa/cxfa_ffapp.cpp
index 7b88626c91..c02fd30e86 100644
--- a/xfa/fxfa/cxfa_ffapp.cpp
+++ b/xfa/fxfa/cxfa_ffapp.cpp
@@ -23,72 +23,6 @@
 #include "xfa/fxfa/cxfa_ffwidgethandler.h"
 #include "xfa/fxfa/cxfa_fontmgr.h"
 
-namespace {
-
-class CXFA_FileRead : public IFX_SeekableReadStream {
- public:
-  explicit CXFA_FileRead(const std::vector<CPDF_Stream*>& streams);
-  ~CXFA_FileRead() override;
-
-  // IFX_SeekableReadStream
-  FX_FILESIZE GetSize() override;
-  bool ReadBlock(void* buffer, FX_FILESIZE offset, size_t size) override;
-
- private:
-  std::vector<CFX_RetainPtr<CPDF_StreamAcc>> m_Data;
-};
-
-CXFA_FileRead::CXFA_FileRead(const std::vector<CPDF_Stream*>& streams) {
-  for (CPDF_Stream* pStream : streams) {
-    m_Data.push_back(pdfium::MakeRetain<CPDF_StreamAcc>(pStream));
-    m_Data.back()->LoadAllData();
-  }
-}
-
-CXFA_FileRead::~CXFA_FileRead() {}
-
-FX_FILESIZE CXFA_FileRead::GetSize() {
-  uint32_t dwSize = 0;
-  for (const auto& acc : m_Data)
-    dwSize += acc->GetSize();
-  return dwSize;
-}
-
-bool CXFA_FileRead::ReadBlock(void* buffer, FX_FILESIZE offset, size_t size) {
-  int32_t iCount = pdfium::CollectionSize<int32_t>(m_Data);
-  int32_t index = 0;
-  while (index < iCount) {
-    const auto& acc = m_Data[index];
-    FX_FILESIZE dwSize = acc->GetSize();
-    if (offset < dwSize)
-      break;
-
-    offset -= dwSize;
-    index++;
-  }
-  while (index < iCount) {
-    const auto& acc = m_Data[index];
-    uint32_t dwSize = acc->GetSize();
-    size_t dwRead = std::min(size, static_cast<size_t>(dwSize - offset));
-    memcpy(buffer, acc->GetData() + offset, dwRead);
-    size -= dwRead;
-    if (size == 0)
-      return true;
-
-    buffer = (uint8_t*)buffer + dwRead;
-    offset = 0;
-    index++;
-  }
-  return false;
-}
-
-}  // namespace
-
-CFX_RetainPtr<IFX_SeekableReadStream> MakeSeekableReadStream(
-    const std::vector<CPDF_Stream*>& streams) {
-  return CFX_RetainPtr<IFX_SeekableReadStream>(new CXFA_FileRead(streams));
-}
-
 CXFA_FFApp::CXFA_FFApp(IXFA_AppProvider* pProvider)
     : m_pProvider(pProvider),
       m_pWidgetMgrDelegate(nullptr),
diff --git a/xfa/fxfa/cxfa_ffapp.h b/xfa/fxfa/cxfa_ffapp.h
index 01235d655b..0a6409d3d1 100644
--- a/xfa/fxfa/cxfa_ffapp.h
+++ b/xfa/fxfa/cxfa_ffapp.h
@@ -25,11 +25,6 @@ class CXFA_FontMgr;
 class IFWL_AdapterTimerMgr;
 class CFWL_WidgetMgrDelegate;
 
-// Layering prevents fxcrt from knowing about CPDF_Streams; this could go
-// in fpdfsdk, but it is XFA-Only.
-CFX_RetainPtr<IFX_SeekableReadStream> MakeSeekableReadStream(
-    const std::vector<CPDF_Stream*>& streams);
-
 class CXFA_FFApp {
  public:
   explicit CXFA_FFApp(IXFA_AppProvider* pProvider);
diff --git a/xfa/fxfa/cxfa_ffapp_unittest.cpp b/xfa/fxfa/cxfa_ffapp_unittest.cpp
index 4d65ccbb2f..fc1d038bac 100644
--- a/xfa/fxfa/cxfa_ffapp_unittest.cpp
+++ b/xfa/fxfa/cxfa_ffapp_unittest.cpp
@@ -13,13 +13,13 @@
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/test_support.h"
 #include "third_party/base/ptr_util.h"
+#include "xfa/fxfa/cxfa_fileread.h"
 
 class CXFAFileReadTest : public pdfium::FPDF_Test {};
 
 TEST_F(CXFAFileReadTest, NoStreams) {
   std::vector<CPDF_Stream*> streams;
-  CFX_RetainPtr<IFX_SeekableReadStream> fileread =
-      MakeSeekableReadStream(streams);
+  auto fileread = pdfium::MakeRetain<CXFA_FileRead>(streams);
 
   uint8_t output_buffer[16];
   memset(output_buffer, 0xbd, sizeof(output_buffer));
@@ -31,8 +31,7 @@ TEST_F(CXFAFileReadTest, EmptyStreams) {
   std::vector<CPDF_Stream*> streams;
   auto stream1 = pdfium::MakeUnique<CPDF_Stream>();
   streams.push_back(stream1.get());
-  CFX_RetainPtr<IFX_SeekableReadStream> fileread =
-      MakeSeekableReadStream(streams);
+  auto fileread = pdfium::MakeRetain<CXFA_FileRead>(streams);
 
   uint8_t output_buffer[16];
   memset(output_buffer, 0xbd, sizeof(output_buffer));
@@ -57,8 +56,7 @@ TEST_F(CXFAFileReadTest, NormalStreams) {
   streams.push_back(stream1.get());
   streams.push_back(stream2.get());
   streams.push_back(stream3.get());
-  CFX_RetainPtr<IFX_SeekableReadStream> fileread =
-      MakeSeekableReadStream(streams);
+  auto fileread = pdfium::MakeRetain<CXFA_FileRead>(streams);
 
   uint8_t output_buffer[16];
   memset(output_buffer, 0xbd, sizeof(output_buffer));
diff --git a/xfa/fxfa/cxfa_ffdoc.cpp b/xfa/fxfa/cxfa_ffdoc.cpp
index 4b6a1e2e07..2bbdfa1b9c 100644
--- a/xfa/fxfa/cxfa_ffdoc.cpp
+++ b/xfa/fxfa/cxfa_ffdoc.cpp
@@ -25,6 +25,7 @@
 #include "xfa/fxfa/cxfa_ffapp.h"
 #include "xfa/fxfa/cxfa_ffdocview.h"
 #include "xfa/fxfa/cxfa_ffwidget.h"
+#include "xfa/fxfa/cxfa_fileread.h"
 #include "xfa/fxfa/cxfa_fontmgr.h"
 #include "xfa/fxfa/parser/cxfa_dataexporter.h"
 #include "xfa/fxfa/parser/cxfa_dataimporter.h"
@@ -315,7 +316,7 @@ bool CXFA_FFDoc::OpenDoc(CPDF_Document* pPDFDoc) {
     return false;
 
   m_pPDFDoc = pPDFDoc;
-  m_pStream = MakeSeekableReadStream(xfaStreams);
+  m_pStream = pdfium::MakeRetain<CXFA_FileRead>(xfaStreams);
   return true;
 }
 
diff --git a/xfa/fxfa/cxfa_fileread.cpp b/xfa/fxfa/cxfa_fileread.cpp
new file mode 100644
index 0000000000..e2ecad2e93
--- /dev/null
+++ b/xfa/fxfa/cxfa_fileread.cpp
@@ -0,0 +1,56 @@
+// Copyright 2017 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.
+
+// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
+
+#include "xfa/fxfa/cxfa_fileread.h"
+
+#include <algorithm>
+
+#include "core/fpdfapi/parser/cpdf_stream_acc.h"
+#include "third_party/base/stl_util.h"
+
+CXFA_FileRead::CXFA_FileRead(const std::vector<CPDF_Stream*>& streams) {
+  for (CPDF_Stream* pStream : streams) {
+    m_Data.push_back(pdfium::MakeRetain<CPDF_StreamAcc>(pStream));
+    m_Data.back()->LoadAllData();
+  }
+}
+
+CXFA_FileRead::~CXFA_FileRead() {}
+
+FX_FILESIZE CXFA_FileRead::GetSize() {
+  uint32_t dwSize = 0;
+  for (const auto& acc : m_Data)
+    dwSize += acc->GetSize();
+  return dwSize;
+}
+
+bool CXFA_FileRead::ReadBlock(void* buffer, FX_FILESIZE offset, size_t size) {
+  int32_t iCount = pdfium::CollectionSize<int32_t>(m_Data);
+  int32_t index = 0;
+  while (index < iCount) {
+    const auto& acc = m_Data[index];
+    FX_FILESIZE dwSize = acc->GetSize();
+    if (offset < dwSize)
+      break;
+
+    offset -= dwSize;
+    index++;
+  }
+  while (index < iCount) {
+    const auto& acc = m_Data[index];
+    uint32_t dwSize = acc->GetSize();
+    size_t dwRead = std::min(size, static_cast<size_t>(dwSize - offset));
+    memcpy(buffer, acc->GetData() + offset, dwRead);
+    size -= dwRead;
+    if (size == 0)
+      return true;
+
+    buffer = static_cast<uint8_t*>(buffer) + dwRead;
+    offset = 0;
+    index++;
+  }
+  return false;
+}
diff --git a/xfa/fxfa/cxfa_fileread.h b/xfa/fxfa/cxfa_fileread.h
new file mode 100644
index 0000000000..0c3348b8d5
--- /dev/null
+++ b/xfa/fxfa/cxfa_fileread.h
@@ -0,0 +1,31 @@
+// Copyright 2017 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.
+
+// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
+
+#ifndef XFA_FXFA_CXFA_FILEREAD_H_
+#define XFA_FXFA_CXFA_FILEREAD_H_
+
+#include <vector>
+
+#include "core/fxcrt/cfx_retain_ptr.h"
+#include "core/fxcrt/fx_stream.h"
+
+class CPDF_Stream;
+class CPDF_StreamAcc;
+
+class CXFA_FileRead : public IFX_SeekableReadStream {
+ public:
+  explicit CXFA_FileRead(const std::vector<CPDF_Stream*>& streams);
+  ~CXFA_FileRead() override;
+
+  // IFX_SeekableReadStream
+  FX_FILESIZE GetSize() override;
+  bool ReadBlock(void* buffer, FX_FILESIZE offset, size_t size) override;
+
+ private:
+  std::vector<CFX_RetainPtr<CPDF_StreamAcc>> m_Data;
+};
+
+#endif  // XFA_FXFA_CXFA_FILEREAD_H_