Avoid getLength in ico decoder.

src/images/SkImageDecoder_libico.cpp

 
 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "SkImageDecoder.h"
@@ skipping 55 matching lines @@
     //  In the case of a 4 bit image with an odd width, we need to add some
     //  so we can go off the end of the drawn bitmap.
     //  Add 4 to ensure that it is still a multiple of 4.
     if (4 == bitCount && (w & 0x1)) {
         return (w + 1) << 2;
     }
     //  Otherwise return 0, which will allow it to be calculated automatically.
     return 0;
 }
 
+// Defined in SkImageDecoder.cpp
+extern size_t copy_stream_to_storage(SkAutoMalloc* storage, SkStream* stream);
+
 bool SkICOImageDecoder::onDecode(SkStream* stream, SkBitmap* bm, Mode mode)
 {
-    size_t length = stream->getLength();
-    SkAutoMalloc autoMal(length);
-    unsigned char* buf = (unsigned char*)autoMal.get();
-    if (stream->read((void*)buf, length) != length) {
+    SkAutoMalloc autoMal;
+    const size_t length = copy_stream_to_storage(&autoMal, stream);
+    if (0 == length) {
         return false;
     }
 
+    unsigned char* buf = (unsigned char*)autoMal.get();
+
     //these should always be the same - should i use for error checking? - what about files that have some
     //incorrect values, but still decode properly?
     int reserved = read2Bytes(buf, 0);    // 0
     int type = read2Bytes(buf, 2);        // 1
     if (reserved != 0 || type != 1)
         return false;
     int count = read2Bytes(buf, 4);
 
     //need to at least have enough space to hold the initial table of info
     if (length < (size_t)(6 + count*16))
@@ skipping 315 matching lines @@
 static SkTRegistry<SkImageDecoder*, SkStream*> gReg(sk_libico_dfactory);
 
 static SkImageDecoder::Format get_format_ico(SkStream* stream) {
     if (is_ico(stream)) {
         return SkImageDecoder::kICO_Format;
     }
     return SkImageDecoder::kUnknown_Format;
 }
 
 static SkTRegistry<SkImageDecoder::Format, SkStream*> gFormatReg(get_format_ico);