PicasaAlbumTableReader for Media Galleries API

chrome/browser/media_galleries/fileapi/picasa/pmp_column_reader.cc

 // Copyright 2013 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 "chrome/browser/media_galleries/fileapi/picasa/pmp_column_reader.h"
 
 #include <cstring>
 
 #include "base/file_util.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/threading/thread_restrictions.h"
 
 namespace picasaimport {
 
 namespace {
 
 const size_t kPmpMaxFilesize = 50*1024*1024; // Maximum of 50 MB.
 
 }  // namespace
 
 PmpColumnReader::PmpColumnReader()
     : length_(0),
       field_type_(PMP_TYPE_INVALID),
-      rows_(0) { }
+      rows_(0) {}
 
-PmpColumnReader::~PmpColumnReader() { }
+PmpColumnReader::~PmpColumnReader() {}
 
-bool PmpColumnReader::Init(const base::FilePath& filepath, uint32* rows_read) {
+bool PmpColumnReader::Init(const base::FilePath& filepath,
+                           const PmpFieldType expected_type,
+                           uint32* rows_read) {
   DCHECK(!data_.get());
   base::ThreadRestrictions::AssertIOAllowed();
 
   int64 length = 0; // Signed temporary.
   if (!file_util::GetFileSize(filepath, &length))
     return false;
 
   length_ = length;
 
   if (length_ < kPmpHeaderSize || length_ > kPmpMaxFilesize)
     return false;
 
   data_.reset(new uint8[length_]);
 
   char* data_begin = reinterpret_cast<char*>(data_.get());
 
   return file_util::ReadFile(filepath, data_begin, length_) &&
-         ParseData(rows_read);
+         ParseData(expected_type, rows_read);
 }
 
 bool PmpColumnReader::ReadString(const uint32 row, std::string* result) const {
   DCHECK(data_.get() != NULL);
   DCHECK_GT(length_, kPmpHeaderSize + row);
 
   if (field_type_ != PMP_TYPE_STRING || row >= rows_)
     return false;
 
   *result = strings_[row];
@@ skipping 37 matching lines @@
   DCHECK(data_.get() != NULL);
   DCHECK_GT(length_, kPmpHeaderSize + row * sizeof(uint64));
 
   if (field_type_ != PMP_TYPE_UINT64 || row >= rows_)
     return false;
 
   *result = reinterpret_cast<uint64*>(data_.get() + kPmpHeaderSize)[row];
   return true;
 }
 
-bool PmpColumnReader::ParseData(uint32* rows_read) {
+bool PmpColumnReader::ParseData(const PmpFieldType expected_type,
+                                uint32* rows_read) {
   DCHECK(data_.get() != NULL);
   DCHECK_GE(length_, kPmpHeaderSize);
 
   // Check all magic bytes.
   if (memcmp(&kPmpMagic1, &data_[kPmpMagic1Offset], sizeof(kPmpMagic1)) != 0 ||
       memcmp(&kPmpMagic2, &data_[kPmpMagic2Offset], sizeof(kPmpMagic2)) != 0 ||
       memcmp(&kPmpMagic3, &data_[kPmpMagic3Offset], sizeof(kPmpMagic3)) != 0 ||
       memcmp(&kPmpMagic4, &data_[kPmpMagic4Offset], sizeof(kPmpMagic4)) != 0) {
     return false;
   }
 
   uint16 field_type_data =
       *(reinterpret_cast<uint16*>(&data_[kPmpFieldType1Offset]));
 
   // Verify if field type matches second declaration
   if (field_type_data !=
       *(reinterpret_cast<uint16*>(&data_[kPmpFieldType2Offset]))) {
     return false;
   }
 
   field_type_ = static_cast<PmpFieldType>(field_type_data);
 
+  if (field_type_ != expected_type)
+    return false;
+
   rows_ = *(reinterpret_cast<uint32*>(&data_[kPmpRowCountOffset]));
 
   size_t body_length = length_ - kPmpHeaderSize;
   size_t expected_body_length = 0;
   switch (field_type_) {
     case PMP_TYPE_STRING:
       expected_body_length = IndexStrings();
       break;
     case PMP_TYPE_UINT32:
       expected_body_length = rows_ * sizeof(uint32);
@@ skipping 39 matching lines @@
 
     strings_.push_back(reinterpret_cast<const char*>(data_cursor));
     data_cursor += length_in_bytes;
     bytes_parsed += length_in_bytes;
   }
 
   return bytes_parsed - kPmpHeaderSize;
 }
 
 }  // namespace picasaimport