ui/base/clipboard/custom_data_helper.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4 //
   5 // TODO(dcheng): For efficiency reasons, consider passing custom data around
   6 // as a vector instead. It allows us to append a
   7 // std::pair<base::string16, base::string16> and swap the deserialized values.
   8
   9 #include "ui/base/clipboard/custom_data_helper.h"
  10
  11 #include <utility>
  12
  13 #include "base/pickle.h"
  14
  15 namespace ui {
  16
  17 namespace {
  18
  19 class SkippablePickle : public base::Pickle {
  20  public:
  21   SkippablePickle(const void* data, size_t data_len);
  22   bool SkipString16(base::PickleIterator* iter);
  23 };
  24
  25 SkippablePickle::SkippablePickle(const void* data, size_t data_len)
  26     : base::Pickle(reinterpret_cast<const char*>(data), data_len) {
  27 }
  28
  29 bool SkippablePickle::SkipString16(base::PickleIterator* iter) {
  30   DCHECK(iter);
  31
  32   int len;
  33   if (!iter->ReadLength(&len))
  34     return false;
  35   return iter->SkipBytes(len * sizeof(base::char16));
  36 }
  37
  38 }  // namespace
  39
  40 void ReadCustomDataTypes(const void* data,
  41                          size_t data_length,
  42                          std::vector<base::string16>* types) {
  43   SkippablePickle pickle(data, data_length);
  44   base::PickleIterator iter(pickle);
  45
  46   size_t size = 0;
  47   if (!iter.ReadSizeT(&size))
  48     return;
  49
  50   // Keep track of the original elements in the types vector. On failure, we
  51   // truncate the vector to the original size since we want to ignore corrupt
  52   // custom data pickles.
  53   size_t original_size = types->size();
  54
  55   for (size_t i = 0; i < size; ++i) {
  56     types->push_back(base::string16());
  57     if (!iter.ReadString16(&types->back()) || !pickle.SkipString16(&iter)) {
  58       types->resize(original_size);
  59       return;
  60     }
  61   }
  62 }
  63
  64 void ReadCustomDataForType(const void* data,
  65                            size_t data_length,
  66                            const base::string16& type,
  67                            base::string16* result) {
  68   SkippablePickle pickle(data, data_length);
  69   base::PickleIterator iter(pickle);
  70
  71   size_t size = 0;
  72   if (!iter.ReadSizeT(&size))
  73     return;
  74
  75   for (size_t i = 0; i < size; ++i) {
  76     base::string16 deserialized_type;
  77     if (!iter.ReadString16(&deserialized_type))
  78       return;
  79     if (deserialized_type == type) {
  80       ignore_result(iter.ReadString16(result));
  81       return;
  82     }
  83     if (!pickle.SkipString16(&iter))
  84       return;
  85   }
  86 }
  87
  88 void ReadCustomDataIntoMap(const void* data,
  89                            size_t data_length,
  90                            std::map<base::string16, base::string16>* result) {
  91   base::Pickle pickle(reinterpret_cast<const char*>(data), data_length);
  92   base::PickleIterator iter(pickle);
  93
  94   size_t size = 0;
  95   if (!iter.ReadSizeT(&size))
  96     return;
  97
  98   for (size_t i = 0; i < size; ++i) {
  99     base::string16 type;
 100     if (!iter.ReadString16(&type)) {
 101       // Data is corrupt, return an empty map.
 102       result->clear();
 103       return;
 104     }
 105     std::pair<std::map<base::string16, base::string16>::iterator, bool>
 106         insert_result = result->insert(std::make_pair(type, base::string16()));
 107     if (!iter.ReadString16(&insert_result.first->second)) {
 108       // Data is corrupt, return an empty map.
 109       result->clear();
 110       return;
 111     }
 112   }
 113 }
 114
 115 void WriteCustomDataToPickle(
 116     const std::map<base::string16, base::string16>& data,
 117     base::Pickle* pickle) {
 118   pickle->WriteSizeT(data.size());
 119   for (std::map<base::string16, base::string16>::const_iterator it =
 120            data.begin();
 121        it != data.end();
 122        ++it) {
 123     pickle->WriteString16(it->first);
 124     pickle->WriteString16(it->second);
 125   }
 126 }
 127
 128 }  // namespace ui