Implement FakeFileAccess.

Update embedder tests to simulate unavailable data and download requests.

Change-Id: I634fa89d2a0c859243e849752936da87568909f4
Reviewed-on: https://pdfium-review.googlesource.com/11890
Commit-Queue: Art Snake <art-snake@yandex-team.ru>
Reviewed-by: dsinclair <dsinclair@chromium.org>

1 files changed, 115 insertions, 0 deletions

diff --git a/testing/fake_file_access.cpp b/testing/fake_file_access.cpp
new file mode 100644
index 0000000000..c69f278102
--- /dev/null
+++ b/testing/fake_file_access.cpp
@@ -0,0 +1,115 @@
+// 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.
+
+#include "testing/fake_file_access.h"
+
+#include <algorithm>
+#include <set>
+#include <utility>
+#include <vector>
+
+#include "core/fxcrt/fx_system.h"
+#include "third_party/base/ptr_util.h"
+
+namespace {
+
+class FileAccessWrapper : public FPDF_FILEACCESS {
+ public:
+  explicit FileAccessWrapper(FakeFileAccess* simulator)
+      : simulator_(simulator) {
+    m_FileLen = simulator_->GetFileSize();
+    m_GetBlock = &GetBlockImpl;
+    m_Param = this;
+  }
+
+  static int GetBlockImpl(void* param,
+                          unsigned long position,
+                          unsigned char* pBuf,
+                          unsigned long size) {
+    return static_cast<FileAccessWrapper*>(param)->simulator_->GetBlock(
+        position, pBuf, size);
+  }
+
+ private:
+  fxcrt::UnownedPtr<FakeFileAccess> simulator_;
+};
+
+class FileAvailImpl : public FX_FILEAVAIL {
+ public:
+  explicit FileAvailImpl(FakeFileAccess* simulator) : simulator_(simulator) {
+    version = 1;
+    IsDataAvail = &IsDataAvailImpl;
+  }
+
+  static FPDF_BOOL IsDataAvailImpl(FX_FILEAVAIL* pThis,
+                                   size_t offset,
+                                   size_t size) {
+    return static_cast<FileAvailImpl*>(pThis)->simulator_->IsDataAvail(offset,
+                                                                       size);
+  }
+
+ private:
+  fxcrt::UnownedPtr<FakeFileAccess> simulator_;
+};
+
+class DownloadHintsImpl : public FX_DOWNLOADHINTS {
+ public:
+  explicit DownloadHintsImpl(FakeFileAccess* simulator)
+      : simulator_(simulator) {
+    version = 1;
+    AddSegment = &AddSegmentImpl;
+  }
+
+  static void AddSegmentImpl(FX_DOWNLOADHINTS* pThis,
+                             size_t offset,
+                             size_t size) {
+    return static_cast<DownloadHintsImpl*>(pThis)->simulator_->AddSegment(
+        offset, size);
+  }
+
+ private:
+  fxcrt::UnownedPtr<FakeFileAccess> simulator_;
+};
+
+}  // namespace
+
+FakeFileAccess::FakeFileAccess(FPDF_FILEACCESS* file_access)
+    : file_access_(file_access),
+      file_access_wrapper_(pdfium::MakeUnique<FileAccessWrapper>(this)),
+      file_avail_(pdfium::MakeUnique<FileAvailImpl>(this)),
+      download_hints_(pdfium::MakeUnique<DownloadHintsImpl>(this)) {
+  ASSERT(file_access_);
+}
+
+FakeFileAccess::~FakeFileAccess() {}
+
+FPDF_BOOL FakeFileAccess::IsDataAvail(size_t offset, size_t size) const {
+  return available_data_.Contains(RangeSet::Range(offset, offset + size));
+}
+
+void FakeFileAccess::AddSegment(size_t offset, size_t size) {
+  requested_data_.Union(RangeSet::Range(offset, offset + size));
+}
+
+unsigned long FakeFileAccess::GetFileSize() {
+  return file_access_->m_FileLen;
+}
+
+int FakeFileAccess::GetBlock(unsigned long position,
+                             unsigned char* pBuf,
+                             unsigned long size) {
+  if (!IsDataAvail(static_cast<size_t>(position), static_cast<size_t>(size)))
+    return false;
+  return file_access_->m_GetBlock(file_access_->m_Param, position, pBuf, size);
+}
+
+void FakeFileAccess::SetRequestedDataAvailable() {
+  available_data_.Union(requested_data_);
+  requested_data_.Clear();
+}
+
+void FakeFileAccess::SetWholeFileAvailable() {
+  available_data_.Union(RangeSet::Range(0, static_cast<size_t>(GetFileSize())));
+  requested_data_.Clear();
+}