fix path op conic bugs

src/pathops/SkPathOpsSimplify.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 "SkAddIntersections.h"
 #include "SkOpCoincidence.h"
 #include "SkOpEdgeBuilder.h"
 #include "SkPathOpsCommon.h"
 #include "SkPathWriter.h"
 
 static bool bridgeWinding(SkOpContourHead* contourList, SkPathWriter* simple,
-        SkChunkAlloc* allocator) {
+        SkChunkAlloc* allocator, bool* closable) {
     bool unsortable = false;
     do {
         SkOpSpan* span = FindSortableTop(contourList);
         if (!span) {
             break;
         }
         SkOpSegment* current = span->segment();
         SkOpSpanBase* start = span->next();
         SkOpSpanBase* end = span;
         SkTDArray<SkOpSpanBase*> chase;
         do {
             if (current->activeWinding(start, end)) {
                 do {
                     if (!unsortable && current->done()) {
                           break;
                     }
                     SkASSERT(unsortable || !current->done());
                     SkOpSpanBase* nextStart = start;
                     SkOpSpanBase* nextEnd = end;
                     SkOpSegment* next = current->findNextWinding(&chase, &nextStart, &nextEnd,
                             &unsortable);
                     if (!next) {
                         if (!unsortable && simple->hasMove()
                                 && current->verb() != SkPath::kLine_Verb
                                 && !simple->isClosed()) {
-                            current->addCurveTo(start, end, simple, true);
+                            if (!current->addCurveTo(start, end, simple)) {
+                                return false;
+                            }
                     #if DEBUG_ACTIVE_SPANS
                             if (!simple->isClosed()) {
                                 DebugShowActiveSpans(contourList);
                             }
                     #endif
                         }
                         break;
                     }
         #if DEBUG_FLOW
             SkDebugf("%s current id=%d from=(%1.9g,%1.9g) to=(%1.9g,%1.9g)\n", __FUNCTION__,
                     current->debugID(), start->pt().fX, start->pt().fY,
                     end->pt().fX, end->pt().fY);
         #endif
-                    current->addCurveTo(start, end, simple, true);
+                    if (!current->addCurveTo(start, end, simple)) {
+                        return false;
+                    }
                     current = next;
                     start = nextStart;
                     end = nextEnd;
                 } while (!simple->isClosed() && (!unsortable || !start->starter(end)->done()));
                 if (current->activeWinding(start, end) && !simple->isClosed()) {
                     SkOpSpan* spanStart = start->starter(end);
                     if (!spanStart->done()) {
-                        current->addCurveTo(start, end, simple, true);
+                        if (!current->addCurveTo(start, end, simple)) {
+                            return false;
+                        }
                         current->markDone(spanStart);
                     }
                 }
                 simple->close();
             } else {
                 SkOpSpanBase* last = current->markAndChaseDone(start, end);
                 if (last && !last->chased()) {
                     last->setChased(true);
                     SkASSERT(!SkPathOpsDebug::ChaseContains(chase, last));
                     *chase.append() = last;
 #if DEBUG_WINDING
                     SkDebugf("%s chase.append id=%d", __FUNCTION__, last->segment()->debugID());
                     if (!last->final()) {
                          SkDebugf(" windSum=%d", last->upCast()->windSum());
                     }
                     SkDebugf("\n");
 #endif
                 }
             }
             current = FindChase(&chase, &start, &end);
         #if DEBUG_ACTIVE_SPANS
             DebugShowActiveSpans(contourList);
         #endif
             if (!current) {
                 break;
             }
         } while (true);
     } while (true);
-    return simple->someAssemblyRequired();
+    *closable = !simple->someAssemblyRequired();
+    return true;
 }
 
 // returns true if all edges were processed
 static bool bridgeXor(SkOpContourHead* contourList, SkPathWriter* simple,
-        SkChunkAlloc* allocator) {
+        SkChunkAlloc* allocator, bool* closable) {
     SkOpSegment* current;
     SkOpSpanBase* start;
     SkOpSpanBase* end;
     bool unsortable = false;
-    bool closable = true;
+    *closable = true;
     while ((current = FindUndone(contourList, &start, &end))) {
         do {
     #if DEBUG_ACTIVE_SPANS
             if (!unsortable && current->done()) {
                 DebugShowActiveSpans(contourList);
             }
     #endif
             SkASSERT(unsortable || !current->done());
             SkOpSpanBase* nextStart = start;
             SkOpSpanBase* nextEnd = end;
             SkOpSegment* next = current->findNextXor(&nextStart, &nextEnd, &unsortable);
             if (!next) {
                 if (!unsortable && simple->hasMove()
                         && current->verb() != SkPath::kLine_Verb
                         && !simple->isClosed()) {
-                    current->addCurveTo(start, end, simple, true);
+                    if (!current->addCurveTo(start, end, simple)) {
+                        return false;
+                    }
             #if DEBUG_ACTIVE_SPANS
                     if (!simple->isClosed()) {
                         DebugShowActiveSpans(contourList);
                     }
             #endif
                 }
                 break;
             }
         #if DEBUG_FLOW
             SkDebugf("%s current id=%d from=(%1.9g,%1.9g) to=(%1.9g,%1.9g)\n", __FUNCTION__,
                     current->debugID(), start->pt().fX, start->pt().fY,
                     end->pt().fX, end->pt().fY);
         #endif
-            current->addCurveTo(start, end, simple, true);
+            if (!current->addCurveTo(start, end, simple)) {
+                return false;
+            }
             current = next;
             start = nextStart;
             end = nextEnd;
         } while (!simple->isClosed() && (!unsortable || !start->starter(end)->done()));
         if (!simple->isClosed()) {
             SkASSERT(unsortable);
             SkOpSpan* spanStart = start->starter(end);
             if (!spanStart->done()) {
-                current->addCurveTo(start, end, simple, true);
+                if (!current->addCurveTo(start, end, simple)) {
+                    return false;
+                }
                 current->markDone(spanStart);
             }
-            closable = false;
+            *closable = false;
         }
         simple->close();
     #if DEBUG_ACTIVE_SPANS
         DebugShowActiveSpans(contourList);
     #endif
     }
-    return closable;
+    return true;
 }
 
 // FIXME : add this as a member of SkPath
 bool Simplify(const SkPath& path, SkPath* result) {
     SkChunkAlloc allocator(4096);  // FIXME: constant-ize, tune
     // returns 1 for evenodd, -1 for winding, regardless of inverse-ness
     SkPath::FillType fillType = path.isInverseFillType() ? SkPath::kInverseEvenOdd_FillType
             : SkPath::kEvenOdd_FillType;
     if (path.isConvex()) {
         if (result != &path) {
@@ skipping 35 matching lines @@
     if (!HandleCoincidence(contourList, &coincidence, &allocator)) {
         return false;
     }
 #if DEBUG_DUMP_ALIGNMENT
     contour.dumpSegments("aligned");
 #endif
     // construct closed contours
     result->reset();
     result->setFillType(fillType);
     SkPathWriter wrapper(*result);
-    if (builder.xorMask() == kWinding_PathOpsMask ? bridgeWinding(contourList, &wrapper, &allocator)
-                : !bridgeXor(contourList, &wrapper, &allocator))
+    bool closable;
+    if (builder.xorMask() == kWinding_PathOpsMask
+            ? !bridgeWinding(contourList, &wrapper, &allocator, &closable)
+            : !bridgeXor(contourList, &wrapper, &allocator, &closable)) {
+        return false;
+    }
+    if (!closable)
     {  // if some edges could not be resolved, assemble remaining fragments
         SkPath temp;
         temp.setFillType(fillType);
         SkPathWriter assembled(temp);
         Assemble(wrapper, &assembled);
         *result = *assembled.nativePath();
         result->setFillType(fillType);
     }
     return true;
 }