1 files changed, 219 insertions, 0 deletions
diff --git a/ui/base/resource/data_pack.cc b/ui/base/resource/data_pack.cc
new file mode 100644
index 0000000..f1cedcc
--- /dev/null
+++ b/ui/base/resource/data_pack.cc
@@ -0,0 +1,219 @@
+// Copyright (c) 2011 The Chromium 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 "ui/base/resource/data_pack.h"
+
+#include <errno.h>
+
+#include "base/file_util.h"
+#include "base/logging.h"
+#include "base/metrics/histogram.h"
+#include "base/ref_counted_memory.h"
+#include "base/string_piece.h"
+
+// For details of the file layout, see
+// http://dev.chromium.org/developers/design-documents/linuxresourcesandlocalizedstrings
+
+namespace {
+
+// A word is four bytes.
+static const size_t kWord = 4;
+
+static const uint32 kFileFormatVersion = 1;
+// Length of file header: version and entry count.
+static const size_t kHeaderLength = 2 * sizeof(uint32);
+
+struct DataPackEntry {
+  uint32 resource_id;
+  uint32 file_offset;
+  uint32 length;
+
+  static int CompareById(const void* void_key, const void* void_entry) {
+    uint32 key = *reinterpret_cast<const uint32*>(void_key);
+    const DataPackEntry* entry =
+        reinterpret_cast<const DataPackEntry*>(void_entry);
+    if (key < entry->resource_id) {
+      return -1;
+    } else if (key > entry->resource_id) {
+      return 1;
+    } else {
+      return 0;
+    }
+  }
+};
+
+COMPILE_ASSERT(sizeof(DataPackEntry) == 12, size_of_header_must_be_twelve);
+
+// We're crashing when trying to load a pak file on Windows.  Add some error
+// codes for logging.
+// http://crbug.com/58056
+enum LoadErrors {
+  INIT_FAILED = 1,
+  BAD_VERSION,
+  INDEX_TRUNCATED,
+  ENTRY_NOT_FOUND,
+
+  LOAD_ERRORS_COUNT,
+};
+
+}  // namespace
+
+namespace ui {
+
+// In .cc for MemoryMappedFile dtor.
+DataPack::DataPack() : resource_count_(0) {
+}
+DataPack::~DataPack() {
+}
+
+bool DataPack::Load(const FilePath& path) {
+  mmap_.reset(new file_util::MemoryMappedFile);
+  if (!mmap_->Initialize(path)) {
+    DLOG(ERROR) << "Failed to mmap datapack";
+    UMA_HISTOGRAM_ENUMERATION("DataPack.Load", INIT_FAILED,
+                              LOAD_ERRORS_COUNT);
+    return false;
+  }
+
+  // Parse the header of the file.
+  // First uint32: version; second: resource count.
+  const uint32* ptr = reinterpret_cast<const uint32*>(mmap_->data());
+  uint32 version = ptr[0];
+  if (version != kFileFormatVersion) {
+    LOG(ERROR) << "Bad data pack version: got " << version << ", expected "
+               << kFileFormatVersion;
+    UMA_HISTOGRAM_ENUMERATION("DataPack.Load", BAD_VERSION,
+                              LOAD_ERRORS_COUNT);
+    mmap_.reset();
+    return false;
+  }
+  resource_count_ = ptr[1];
+
+  // Sanity check the file.
+  // 1) Check we have enough entries.
+  if (kHeaderLength + resource_count_ * sizeof(DataPackEntry) >
+      mmap_->length()) {
+    LOG(ERROR) << "Data pack file corruption: too short for number of "
+                  "entries specified.";
+    UMA_HISTOGRAM_ENUMERATION("DataPack.Load", INDEX_TRUNCATED,
+                              LOAD_ERRORS_COUNT);
+    mmap_.reset();
+    return false;
+  }
+  // 2) Verify the entries are within the appropriate bounds.
+  for (size_t i = 0; i < resource_count_; ++i) {
+    const DataPackEntry* entry = reinterpret_cast<const DataPackEntry*>(
+        mmap_->data() + kHeaderLength + (i * sizeof(DataPackEntry)));
+    if (entry->file_offset + entry->length > mmap_->length()) {
+      LOG(ERROR) << "Entry #" << i << " in data pack points off end of file. "
+                 << "Was the file corrupted?";
+      UMA_HISTOGRAM_ENUMERATION("DataPack.Load", ENTRY_NOT_FOUND,
+                                LOAD_ERRORS_COUNT);
+      mmap_.reset();
+      return false;
+    }
+  }
+
+  return true;
+}
+
+bool DataPack::GetStringPiece(uint32 resource_id,
+                              base::StringPiece* data) const {
+  // It won't be hard to make this endian-agnostic, but it's not worth
+  // bothering to do right now.
+#if defined(__BYTE_ORDER)
+  // Linux check
+  COMPILE_ASSERT(__BYTE_ORDER == __LITTLE_ENDIAN,
+                 datapack_assumes_little_endian);
+#elif defined(__BIG_ENDIAN__)
+  // Mac check
+  #error DataPack assumes little endian
+#endif
+
+  DataPackEntry* target = reinterpret_cast<DataPackEntry*>(
+      bsearch(&resource_id, mmap_->data() + kHeaderLength, resource_count_,
+              sizeof(DataPackEntry), DataPackEntry::CompareById));
+  if (!target) {
+    return false;
+  }
+
+  data->set(mmap_->data() + target->file_offset, target->length);
+  return true;
+}
+
+RefCountedStaticMemory* DataPack::GetStaticMemory(uint32 resource_id) const {
+  base::StringPiece piece;
+  if (!GetStringPiece(resource_id, &piece))
+    return NULL;
+
+  return new RefCountedStaticMemory(
+      reinterpret_cast<const unsigned char*>(piece.data()), piece.length());
+}
+
+// static
+bool DataPack::WritePack(const FilePath& path,
+                         const std::map<uint32, base::StringPiece>& resources) {
+  FILE* file = file_util::OpenFile(path, "wb");
+  if (!file)
+    return false;
+
+  if (fwrite(&kFileFormatVersion, 1, kWord, file) != kWord) {
+    LOG(ERROR) << "Failed to write file version";
+    file_util::CloseFile(file);
+    return false;
+  }
+
+  // Note: the python version of this function explicitly sorted keys, but
+  // std::map is a sorted associative container, we shouldn't have to do that.
+  uint32 entry_count = resources.size();
+  if (fwrite(&entry_count, 1, kWord, file) != kWord) {
+    LOG(ERROR) << "Failed to write entry count";
+    file_util::CloseFile(file);
+    return false;
+  }
+
+  // Each entry is 3 uint32s.
+  uint32 index_length = entry_count * 3 * kWord;
+  uint32 data_offset = kHeaderLength + index_length;
+  for (std::map<uint32, base::StringPiece>::const_iterator it =
+           resources.begin();
+       it != resources.end(); ++it) {
+    if (fwrite(&it->first, 1, kWord, file) != kWord) {
+      LOG(ERROR) << "Failed to write id for " << it->first;
+      file_util::CloseFile(file);
+      return false;
+    }
+
+    if (fwrite(&data_offset, 1, kWord, file) != kWord) {
+      LOG(ERROR) << "Failed to write offset for " << it->first;
+      file_util::CloseFile(file);
+      return false;
+    }
+
+    uint32 len = it->second.length();
+    if (fwrite(&len, 1, kWord, file) != kWord) {
+      LOG(ERROR) << "Failed to write length for " << it->first;
+      file_util::CloseFile(file);
+      return false;
+    }
+
+    data_offset += len;
+  }
+
+  for (std::map<uint32, base::StringPiece>::const_iterator it =
+           resources.begin();
+       it != resources.end(); ++it) {
+    if (fwrite(it->second.data(), it->second.length(), 1, file) != 1) {
+      LOG(ERROR) << "Failed to write data for " << it->first;
+      file_util::CloseFile(file);
+      return false;
+    }
+  }
+
+  file_util::CloseFile(file);
+
+  return true;
+}
+
+}  // namespace ui