From 9a9df873c619cd08ac6fb14a510135f29d8cccd1 Mon Sep 17 00:00:00 2001
From: "evan@chromium.org"
<evan@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98>
Date: Thu, 8 Jan 2009 19:51:09 +0000
Subject: Data pack file reader and unit test, used for resources on Linux.
See http://dev.chromium.org/developers/design-documents/linuxresourcesandlocalizedstrings for more details.
Review URL: http://codereview.chromium.org/17253
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@7751 0039d316-1c4b-4281-b951-d872f2087c98
---
base/base_lib.scons | 1 +
base/base_unittests.scons | 5 ++
base/data/data_pack_unittest/sample.pak | Bin 0 -> 80 bytes
base/data_pack.cc | 109 ++++++++++++++++++++++++++++++++
base/data_pack.h | 46 ++++++++++++++
base/data_pack_unittest.cc | 42 ++++++++++++
6 files changed, 203 insertions(+)
create mode 100644 base/data/data_pack_unittest/sample.pak
create mode 100644 base/data_pack.cc
create mode 100644 base/data_pack.h
create mode 100644 base/data_pack_unittest.cc
diff --git a/base/base_lib.scons b/base/base_lib.scons
index 976a899..0dd3673 100644
--- a/base/base_lib.scons
+++ b/base/base_lib.scons
@@ -361,6 +361,7 @@ if env.Bit('linux'):
'atomicops_internals_x86_gcc.cc',
'base_paths_linux.cc',
'clipboard_linux.cc',
+ 'data_pack.cc',
'file_util_linux.cc',
'file_version_info_linux.cc',
'hmac_nss.cc',
diff --git a/base/base_unittests.scons b/base/base_unittests.scons
index 66be1f3..4b0c2e8 100644
--- a/base/base_unittests.scons
+++ b/base/base_unittests.scons
@@ -131,6 +131,11 @@ if env.Bit('posix'):
'gfx/native_theme_unittest.cc',
)
+if env.Bit('linux'):
+ input_files.Append(
+ 'data_pack_unittest.cc',
+ )
+
if env.Bit('mac'):
# Remove files that still need to be ported from the input_files list.
# TODO(port): delete files from this list as they get ported.
diff --git a/base/data/data_pack_unittest/sample.pak b/base/data/data_pack_unittest/sample.pak
new file mode 100644
index 0000000..fdbe2b5
Binary files /dev/null and b/base/data/data_pack_unittest/sample.pak differ
diff --git a/base/data_pack.cc b/base/data_pack.cc
new file mode 100644
index 0000000..17db8c4
--- /dev/null
+++ b/base/data_pack.cc
@@ -0,0 +1,109 @@
+// Copyright (c) 2008 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 "base/data_pack.h"
+
+#include "base/file_util.h"
+#include "base/logging.h"
+#include "base/string_piece.h"
+
+// For details of the file layout, see
+// http://dev.chromium.org/developers/design-documents/linuxresourcesandlocalizedstrings
+
+namespace {
+static const uint32_t kFileFormatVersion = 1;
+// Length of file header: version and entry count.
+static const size_t kHeaderLength = 2 * sizeof(uint32_t);
+
+struct DataPackEntry {
+ uint32_t resource_id;
+ uint32_t file_offset;
+ uint32_t length;
+
+ static int CompareById(const void* void_key, const void* void_entry) {
+ uint32_t key = *reinterpret_cast<const uint32_t*>(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;
+ }
+ }
+} __attribute((packed));
+
+} // anonymous namespace
+
+namespace base {
+
+// 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)) {
+ mmap_.reset();
+ return false;
+ }
+
+ // Parse the header of the file.
+ // First uint32_t: version; second: resource count.
+ const uint32* ptr = reinterpret_cast<const uint32_t*>(mmap_->data());
+ uint32 version = ptr[0];
+ if (version != kFileFormatVersion) {
+ LOG(ERROR) << "Bad data pack version: got " << version << ", expected "
+ << kFileFormatVersion;
+ 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.";
+ 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?";
+ mmap_.reset();
+ return false;
+ }
+ }
+
+ return true;
+}
+
+bool DataPack::Get(uint32_t resource_id, StringPiece* data) {
+ // It won't be hard to make this endian-agnostic, but it's not worth
+ // bothering to do right now.
+ COMPILE_ASSERT(__BYTE_ORDER == __LITTLE_ENDIAN,
+ datapack_assumes_little_endian);
+
+ DataPackEntry* target = reinterpret_cast<DataPackEntry*>(
+ bsearch(&resource_id, mmap_->data() + kHeaderLength, resource_count_,
+ sizeof(DataPackEntry), DataPackEntry::CompareById));
+ if (!target) {
+ LOG(ERROR) << "No resource found with id: " << resource_id;
+ return false;
+ }
+
+ data->set(mmap_->data() + target->file_offset, target->length);
+ return true;
+}
+
+} // namespace base
diff --git a/base/data_pack.h b/base/data_pack.h
new file mode 100644
index 0000000..1836552
--- /dev/null
+++ b/base/data_pack.h
@@ -0,0 +1,46 @@
+// Copyright (c) 2008 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.
+
+// DataPack represents a read-only view onto an on-disk file that contains
+// (key, value) pairs of data. It's used to store static resources like
+// translation strings and images.
+
+#ifndef BASE_DATA_PACK_H_
+#define BASE_DATA_PACK_H_
+
+#include "base/basictypes.h"
+#include "base/scoped_ptr.h"
+
+namespace file_util {
+ class MemoryMappedFile;
+}
+class FilePath;
+class StringPiece;
+
+namespace base {
+
+class DataPack {
+ public:
+ DataPack();
+ ~DataPack();
+
+ // Load a pack file from |path|, returning false on error.
+ bool Load(const FilePath& path);
+
+ // Get resource by id |resource_id|, filling in |data|.
+ // The data is owned by the DataPack object and should not be modified.
+ // Returns false if the resource id isn't found.
+ bool Get(uint32_t resource_id, StringPiece* data);
+
+ private:
+ // The memory-mapped data.
+ scoped_ptr<file_util::MemoryMappedFile> mmap_;
+
+ // Number of resources in the data.
+ size_t resource_count_;
+};
+
+} // namespace base
+
+#endif // BASE_DATA_PACK_H_
diff --git a/base/data_pack_unittest.cc b/base/data_pack_unittest.cc
new file mode 100644
index 0000000..1f6b264
--- /dev/null
+++ b/base/data_pack_unittest.cc
@@ -0,0 +1,42 @@
+// Copyright (c) 2008 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 "base/data_pack.h"
+
+#include "base/file_path.h"
+#include "base/logging.h"
+#include "base/path_service.h"
+#include "base/string_piece.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+class DataPackTest : public testing::Test {
+ public:
+ DataPackTest() {
+ PathService::Get(base::DIR_SOURCE_ROOT, &data_path_);
+ data_path_ = data_path_.Append(
+ FILE_PATH_LITERAL("base/data/data_pack_unittest/sample.pak"));
+ }
+
+ FilePath data_path_;
+};
+
+TEST_F(DataPackTest, Load) {
+ base::DataPack pack;
+ ASSERT_TRUE(pack.Load(data_path_));
+
+ StringPiece data;
+ ASSERT_TRUE(pack.Get(4, &data));
+ EXPECT_EQ("this is id 4", data);
+ ASSERT_TRUE(pack.Get(6, &data));
+ EXPECT_EQ("this is id 6", data);
+
+ // Try reading zero-length data blobs, just in case.
+ ASSERT_TRUE(pack.Get(1, &data));
+ EXPECT_EQ(0U, data.length());
+ ASSERT_TRUE(pack.Get(10, &data));
+ EXPECT_EQ(0U, data.length());
+
+ // Try looking up an invalid key.
+ ASSERT_FALSE(pack.Get(140, &data));
+}
--
cgit v1.1