Line data    Source code

       1             : /*
       2             :  * Copyright 2011 Google Inc. All Rights Reserved.
       3             :  *
       4             :  * Licensed under the Apache License, Version 2.0 (the "License");
       5             :  * you may not use this file except in compliance with the License.
       6             :  * You may obtain a copy of the License at
       7             :  *
       8             :  *      http://www.apache.org/licenses/LICENSE-2.0
       9             :  *
      10             :  * Unless required by applicable law or agreed to in writing, software
      11             :  * distributed under the License is distributed on an "AS IS" BASIS,
      12             :  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
      13             :  * See the License for the specific language governing permissions and
      14             :  * limitations under the License.
      15             :  */
      16             : 
      17             : #if defined (WIN32)
      18             : #include <windows.h>
      19             : #endif
      20             : 
      21             : #include <string.h>
      22             : 
      23             : #include <algorithm>
      24             : 
      25             : #include "sfntly/port/memory_input_stream.h"
      26             : #include "sfntly/port/exception_type.h"
      27             : 
      28             : namespace sfntly {
      29             : 
      30           0 : MemoryInputStream::MemoryInputStream()
      31             :     : buffer_(NULL),
      32             :       position_(0),
      33           0 :       length_(0) {
      34           0 : }
      35             : 
      36           0 : MemoryInputStream::~MemoryInputStream() {
      37           0 :   Close();
      38           0 : }
      39             : 
      40           0 : int32_t MemoryInputStream::Available() {
      41           0 :   return length_ - position_;
      42             : }
      43             : 
      44           0 : void MemoryInputStream::Close() {
      45           0 : }
      46             : 
      47           0 : void MemoryInputStream::Mark(int32_t readlimit) {
      48             :   // NOP
      49             :   UNREFERENCED_PARAMETER(readlimit);
      50           0 : }
      51             : 
      52           0 : bool MemoryInputStream::MarkSupported() {
      53           0 :   return false;
      54             : }
      55             : 
      56           0 : int32_t MemoryInputStream::Read() {
      57           0 :   if (!buffer_) {
      58             : #if !defined (SFNTLY_NO_EXCEPTION)
      59             :     throw IOException("no memory attached");
      60             : #endif
      61           0 :     return 0;
      62             :   }
      63           0 :   if (position_ >= length_) {
      64             : #if !defined (SFNTLY_NO_EXCEPTION)
      65             :     throw IOException("eof reached");
      66             : #endif
      67           0 :     return 0;
      68             :   }
      69           0 :   byte_t value = buffer_[position_++];
      70           0 :   return value;
      71             : }
      72             : 
      73           0 : int32_t MemoryInputStream::Read(ByteVector* b) {
      74           0 :   return Read(b, 0, b->size());
      75             : }
      76             : 
      77           0 : int32_t MemoryInputStream::Read(ByteVector* b, int32_t offset, int32_t length) {
      78           0 :   assert(b);
      79           0 :   if (!buffer_) {
      80             : #if !defined (SFNTLY_NO_EXCEPTION)
      81             :     throw IOException("no memory attached");
      82             : #endif
      83           0 :     return 0;
      84             :   }
      85           0 :   if (position_ >= length_) {
      86             : #if !defined (SFNTLY_NO_EXCEPTION)
      87             :     throw IOException("eof reached");
      88             : #endif
      89           0 :     return 0;
      90             :   }
      91           0 :   size_t read_count = std::min<size_t>(length_ - position_, length);
      92           0 :   if (b->size() < (size_t)(offset + read_count)) {
      93           0 :     b->resize((size_t)(offset + read_count));
      94             :   }
      95           0 :   memcpy(&((*b)[offset]), buffer_ + position_, read_count);
      96           0 :   position_ += read_count;
      97           0 :   return read_count;
      98             : }
      99             : 
     100           0 : void MemoryInputStream::Reset() {
     101             :   // NOP
     102           0 : }
     103             : 
     104           0 : int64_t MemoryInputStream::Skip(int64_t n) {
     105           0 :   if (!buffer_) {
     106             : #if !defined (SFNTLY_NO_EXCEPTION)
     107             :     throw IOException("no memory attached");
     108             : #endif
     109           0 :     return 0;
     110             :   }
     111           0 :   int64_t skip_count = 0;
     112           0 :   if (n < 0) {  // move backwards
     113           0 :     skip_count = std::max<int64_t>(0 - (int64_t)position_, n);
     114           0 :     position_ -= (size_t)(0 - skip_count);
     115             :   } else {
     116           0 :     skip_count = std::min<size_t>(length_ - position_, (size_t)n);
     117           0 :     position_ += (size_t)skip_count;
     118             :   }
     119           0 :   return skip_count;
     120             : }
     121             : 
     122           0 : void MemoryInputStream::Unread(ByteVector* b) {
     123           0 :   Unread(b, 0, b->size());
     124           0 : }
     125             : 
     126           0 : void MemoryInputStream::Unread(ByteVector* b, int32_t offset, int32_t length) {
     127           0 :   assert(b);
     128           0 :   assert(b->size() >= size_t(offset + length));
     129           0 :   if (!buffer_) {
     130             : #if !defined (SFNTLY_NO_EXCEPTION)
     131             :     throw IOException("no memory attached");
     132             : #endif
     133           0 :     return;
     134             :   }
     135           0 :   size_t unread_count = std::min<size_t>(position_, length);
     136           0 :   position_ -= unread_count;
     137           0 :   Read(b, offset, length);
     138           0 :   position_ -= unread_count;
     139             : }
     140             : 
     141           0 : bool MemoryInputStream::Attach(const byte_t* buffer, size_t length) {
     142           0 :   assert(buffer);
     143           0 :   assert(length);
     144           0 :   buffer_ = buffer;
     145           0 :   length_ = length;
     146           0 :   return true;
     147             : }
     148             : 
     149             : }  // namespace sfntly