use SkData::NewUninitialized

include/core/SkStream.h

 /*
  * 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.
  */
 
 #ifndef SkStream_DEFINED
 #define SkStream_DEFINED
 
@@ skipping 38 matching lines @@
 
     /** Reads or skips size number of bytes.
      *  If buffer == NULL, skip size bytes, return how many were skipped.
      *  If buffer != NULL, copy size bytes into buffer, return how many were copied.
      *  @param buffer when NULL skip size bytes, otherwise copy size bytes into buffer
      *  @param size the number of bytes to skip or copy
      *  @return the number of bytes actually read.
      */
     virtual size_t read(void* buffer, size_t size) = 0;
 
+    /**
+     *  Attempt to read size bytes into a SkData. If the read success, return the data,
+     *  else return NULL. Either way the stream's cursor may have been changed as a result
+     *  of calling read().
+     */
+    SkData* readIntoData(size_t size);

[bungeman-skia, 2014/09/12 14:50:27]

Eck, not another thing on SkStream...

It seems like this might be better (both in implementation and use) as

SkData* SkData::NewFromStream(SkStream* stream, size_t length = SIZE_MAX)

This gets this away from being yet another helper on SkStream. Since this isn't
virtual and always just calls public api and makes a copy of the stream data
anyway, it seems more clear that this is a SkData creator.

In the future this could even rely on a virtual 'SkData* refData()' which would
replace or augment getMemoryBase to not create a copy if the whole stream needed
to be duplicated into an SkData.

At the very least this would go into the readXXX non-virtual ghetto below.

[reed1, 2014/09/12 18:55:17]

Done.

+
     /** Skip size number of bytes.
      *  @return the actual number bytes that could be skipped.
      */
     size_t skip(size_t size) {
         return this->read(NULL, size);
     }
 
     /** Returns true when all the bytes in the stream have been read.
      *  This may return true early (when there are no more bytes to be read)
      *  or late (after the first unsuccessful read).
@@ skipping 387 matching lines @@
 
 private:
     size_t fBytesWritten;
     typedef SkWStream INHERITED;
 };
 
 // for now
 typedef SkFILEStream SkURLStream;
 
 #endif