Add buffer helper to read directly into SkString to avoid extra copying

src/core/SkOrderedReadBuffer.cpp

 
 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkErrorInternals.h"
@@ skipping 70 matching lines @@
 }
 
 uint32_t SkOrderedReadBuffer::readUInt() {
     return fReader.readU32();
 }
 
 int32_t SkOrderedReadBuffer::read32() {
     return fReader.readInt();
 }
 
+void SkOrderedReadBuffer::readString(SkString& string) {
+    size_t len;
+    string.set(fReader.readString(&len), len);

[reed1, 2013/05/20 13:42:47]

Parameter evaluation order is undefined, so it is possible that the 2nd arg will
be evaluated first, passing an uninitialized value for len. Probably should use
the same pattern as we do below in readString().

[djsollen, 2013/05/21 12:17:17]

Done.

+}
+
 char* SkOrderedReadBuffer::readString() {

[reed1, 2013/05/20 13:42:47]

Suggestion: rename this to something other than String, indicating that it was
allocated via malloc.

e.g.
readCString
readCStringWithMalloc

... do we even need it, how that you're adding a cool version of readString?

[djsollen, 2013/05/21 12:17:17]

removed and updated the one caller to use the new readString call.

On 2013/05/20 13:42:47, reed1 wrote:

-    const char* string = fReader.readString();
-    const size_t length = strlen(string);
+    size_t length;
+    const char* string = fReader.readString(&length);
     char* value = (char*)sk_malloc_throw(length + 1);
     strcpy(value, string);
     return value;
 }
 
 void* SkOrderedReadBuffer::readEncodedString(size_t* length, SkPaint::TextEncoding encoding) {
     SkDEBUGCODE(int32_t encodingType = ) fReader.readInt();
     SkASSERT(encodingType == encoding);
     *length =  fReader.readInt();
     void* data = sk_malloc_throw(*length);
@@ skipping 163 matching lines @@
         if (sizeRecorded != sizeRead) {
             // we could try to fix up the offset...
             sk_throw();
         }
     } else {
         // we must skip the remaining data
         fReader.skip(sizeRecorded);
     }
     return obj;
 }