change colortable to use factory for reinflating, check for empty

src/core/SkColorTable.cpp

 
 /*
  * Copyright 2009 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 "SkColorTable.h"
@@ skipping 14 matching lines @@
 SkColorTable::SkColorTable(const SkPMColor colors[], int count) {
     SkASSERT(0 == count || colors);
     if (count < 0) {
         count = 0;
     } else if (count > 256) {
         count = 256;
     }
     this->init(colors, count);
 }
 
+SkColorTable::SkColorTable(SkPMColor* colors, int count, AllocatedWithMalloc)
+    : fColors(colors)
+    , fCount(count)
+{
+    SkASSERT(count > 0 && count <= 255);

[hal.canary, 2015/08/28 18:28:02]

why not 256?

+    SkASSERT(colors);
+}
+
 SkColorTable::~SkColorTable() {
     sk_free(fColors);
     // f16BitCache frees itself
 }
 
 #include "SkColorPriv.h"
 
 namespace {
 struct Build16BitCache {
     const SkPMColor* fColors;
@@ skipping 11 matching lines @@
 
 void SkColorTable::Free16BitCache(uint16_t* cache) { sk_free(cache); }
 
 const uint16_t* SkColorTable::read16BitCache() const {
     const Build16BitCache create = { fColors, fCount };
     return f16BitCache.get(create);
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
+#if 0
 SkColorTable::SkColorTable(SkReadBuffer& buffer) {
     if (buffer.isVersionLT(SkReadBuffer::kRemoveColorTableAlpha_Version)) {
         /*fAlphaType = */buffer.readUInt();
     }
 
     fCount = buffer.getArrayCount();
     size_t allocSize = fCount * sizeof(SkPMColor);
     SkDEBUGCODE(bool success = false;)
     if (buffer.validateAvailable(allocSize)) {
         fColors = (SkPMColor*)sk_malloc_throw(allocSize);
         SkDEBUGCODE(success =) buffer.readColorArray(fColors, fCount);
     } else {
         fCount = 0;
         fColors = nullptr;
     }
 #ifdef SK_DEBUG
     SkASSERT((unsigned)fCount <= 256);
     SkASSERT(success);
 #endif
 }
+#endif
 
 void SkColorTable::writeToBuffer(SkWriteBuffer& buffer) const {
     buffer.writeColorArray(fColors, fCount);
 }
+
+SkColorTable* SkColorTable::Create(SkReadBuffer& buffer) {
+    if (buffer.isVersionLT(SkReadBuffer::kRemoveColorTableAlpha_Version)) {
+        /*fAlphaType = */buffer.readUInt();
+    }
+
+    const int count = buffer.getArrayCount();
+    if (0 == count) {
+        return new SkColorTable(nullptr, 0);
+    }
+
+    if (count < 0 || count > 255) {
+        buffer.validate(false);
+        return nullptr;
+    }
+
+    const size_t allocSize = count * sizeof(SkPMColor);
+    SkAutoTDelete<SkPMColor> colors((SkPMColor*)sk_malloc_throw(allocSize));
+    if (!buffer.readColorArray(colors, count)) {
+        return nullptr;
+    }
+
+    return new SkColorTable(colors.detach(), count, kAllocatedWithMalloc);
+}
+