change SkColorTable to be immutable

src/images/SkImageDecoder_libgif.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 207 matching lines @@
             }
 
             // now we decode the colortable
             int colorCount = 0;
             {
                 const ColorMapObject* cmap = find_colormap(gif);
                 if (NULL == cmap) {
                     return error_return(gif, *bm, "null cmap");
                 }
 
+                SkPMColor colorPtr[256]; // storage for worse-case

[scroggo, 2013/10/07 21:58:42]

worst*

[reed1, 2013/10/09 12:19:54]

Done.

                 colorCount = cmap->ColorCount;
-                SkColorTable* ctable = SkNEW_ARGS(SkColorTable, (colorCount));
-                SkPMColor* colorPtr = ctable->lockColors();
+                SkAlphaType alphaType = kOpaque_SkAlphaType;
                 for (int index = 0; index < colorCount; index++)
                     colorPtr[index] = SkPackARGB32(0xFF,
                                                    cmap->Colors[index].Red,
                                                    cmap->Colors[index].Green,
                                                    cmap->Colors[index].Blue);
 
                 transpIndex = find_transpIndex(temp_save, colorCount);
-                if (transpIndex < 0)
-                    ctable->setFlags(ctable->getFlags() | SkColorTable::kColorsAreOpaque_Flag);
-                else
+                if (transpIndex >= 0) {
+                    SkASSERT((unsigned)transpIndex < (unsigned)colorCount);
                     colorPtr[transpIndex] = 0; // ram in a transparent SkPMColor
-                ctable->unlockColors(true);
+                    alphaType = kPremul_SkAlphaType;
+                }
 
-                SkAutoUnref aurts(ctable);
+                SkAutoTUnref<SkColorTable> ctable(SkNEW_ARGS(SkColorTable,
+                                                  (colorPtr, colorCount,
+                                                   alphaType)));
                 if (!this->allocPixelRef(bm, ctable)) {
                     return error_return(gif, *bm, "allocPixelRef");
                 }
             }
 
             SkAutoLockPixels alp(*bm);
 
             // time to decode the scanlines
             //
             uint8_t*  scanline = bm->getAddr8(0, 0);
@@ skipping 123 matching lines @@
 static SkImageDecoder_DecodeReg gReg(sk_libgif_dfactory);
 
 static SkImageDecoder::Format get_format_gif(SkStreamRewindable* stream) {
     if (is_gif(stream)) {
         return SkImageDecoder::kGIF_Format;
     }
     return SkImageDecoder::kUnknown_Format;
 }
 
 static SkImageDecoder_FormatReg gFormatReg(get_format_gif);