move failable work outside of constructors for SkGlyphCache and SkScalerContextGDI. If we fail, try…

src/core/SkGlyphCache.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 "SkGlyphCache.h"
@@ skipping 35 matching lines @@
 #endif
 #define RecordHashCollision() RecordHashCollisionIf(true)
 
 ///////////////////////////////////////////////////////////////////////////////
 
 // so we don't grow our arrays a lot
 #define kMinGlyphCount      16
 #define kMinGlyphImageSize  (16*2)
 #define kMinAllocAmount     ((sizeof(SkGlyph) + kMinGlyphImageSize) * kMinGlyphCount)
 
-SkGlyphCache::SkGlyphCache(SkTypeface* typeface, const SkDescriptor* desc)
-        : fGlyphAlloc(kMinAllocAmount) {
+SkGlyphCache::SkGlyphCache(SkTypeface* typeface, const SkDescriptor* desc, SkScalerContext* ctx)
+        : fScalerContext(ctx), fGlyphAlloc(kMinAllocAmount) {
     SkASSERT(typeface);
+    SkASSERT(desc);
+    SkASSERT(ctx);
 
     fPrev = fNext = NULL;
 
     fDesc = desc->copy();
-    fScalerContext = typeface->createScalerContext(desc);
     fScalerContext->getFontMetrics(&fFontMetrics);
 
     // init to 0 so that all of the pointers will be null
     memset(fGlyphHash, 0, sizeof(fGlyphHash));
     // init with 0xFF so that the charCode field will be -1, which is invalid
     memset(fCharToGlyphHash, 0xFF, sizeof(fCharToGlyphHash));
 
     fMemoryUsed = sizeof(*this);
 
     fGlyphArray.setReserve(kMinGlyphCount);
@@ skipping 508 matching lines @@
             goto FOUND_IT;
         }
     }
 
     /* Release the mutex now, before we create a new entry (which might have
         side-effects like trying to access the cache/mutex (yikes!)
     */
     ac.release();           // release the mutex now
     insideMutex = false;    // can't use globals anymore
 
-    cache = SkNEW_ARGS(SkGlyphCache, (typeface, desc));
+    // Check if we can create a scaler-context before creating the glyphcache.
+    // If not, we may have exhausted OS/font resources, so try purging the
+    // cache once and try again.
+    {
+        SkScalerContext* ctx = typeface->createScalerContext(desc);
+        if (!ctx) {
+            getSharedGlobals().purgeAll();
+            ctx = typeface->createScalerContext(desc);
+            if (!ctx) {
+                sk_throw();
+            }
+        }
+        cache = SkNEW_ARGS(SkGlyphCache, (typeface, desc, ctx));
+    }
 
 FOUND_IT:
 
     AutoValidate av(cache);
 
     if (proc(cache, context)) {   // stay detached
         if (insideMutex) {
             SkASSERT(globals.fTotalMemoryUsed >= cache->fMemoryUsed);
             globals.fTotalMemoryUsed -= cache->fMemoryUsed;
 #ifdef USE_CACHE_HASH
@@ skipping 162 matching lines @@
     return tls ? tls->getFontCacheLimit() : 0;
 }
 
 void SkGraphics::SetTLSFontCacheLimit(size_t bytes) {
     if (0 == bytes) {
         SkGlyphCache_Globals::DeleteTLS();
     } else {
         SkGlyphCache_Globals::GetTLS().setFontCacheLimit(bytes);
     }
 }