fix misc asserts and checks found by fuzzer

src/effects/Sk1DPathEffect.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 "Sk1DPathEffect.h"
@@ skipping 17 matching lines @@
         }
     } while (meas.nextContour());
     return true;
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 SkPath1DPathEffect::SkPath1DPathEffect(const SkPath& path, SkScalar advance,
     SkScalar phase, Style style) : fPath(path)
 {
-    if (advance <= 0 || path.isEmpty()) {
-        SkDEBUGF(("SkPath1DPathEffect can't use advance <= 0\n"));
-        fAdvance = 0;   // signals we can't draw anything
-        fInitialOffset = 0;
-        fStyle = kStyleCount;
+    SkASSERT(advance > 0 && !path.isEmpty());
+    // cleanup their phase parameter, inverting it so that it becomes an
+    // offset along the path (to match the interpretation in PostScript)
+    if (phase < 0) {
+        phase = -phase;
+        if (phase > advance) {
+            phase = SkScalarMod(phase, advance);
+        }
     } else {
-        // cleanup their phase parameter, inverting it so that it becomes an
-        // offset along the path (to match the interpretation in PostScript)
-        if (phase < 0) {
-            phase = -phase;
-            if (phase > advance) {
-                phase = SkScalarMod(phase, advance);
-            }
-        } else {
-            if (phase > advance) {
-                phase = SkScalarMod(phase, advance);
-            }
-            phase = advance - phase;
+        if (phase > advance) {
+            phase = SkScalarMod(phase, advance);
         }
-        // now catch the edge case where phase == advance (within epsilon)
-        if (phase >= advance) {
-            phase = 0;
-        }
-        SkASSERT(phase >= 0);
+        phase = advance - phase;
+    }
+    // now catch the edge case where phase == advance (within epsilon)
+    if (phase >= advance) {
+        phase = 0;
+    }
+    SkASSERT(phase >= 0);
 
-        fAdvance = advance;
-        fInitialOffset = phase;
+    fAdvance = advance;
+    fInitialOffset = phase;
 
-        if ((unsigned)style >= kStyleCount) {
-            SkDEBUGF(("SkPath1DPathEffect style enum out of range %d\n", style));
-        }
-        fStyle = style;
+    if ((unsigned)style > kMorph_Style) {
+        SkDEBUGF(("SkPath1DPathEffect style enum out of range %d\n", style));
     }
+    fStyle = style;
 }
 
 bool SkPath1DPathEffect::filterPath(SkPath* dst, const SkPath& src,
                             SkStrokeRec* rec, const SkRect* cullRect) const {
     if (fAdvance > 0) {
         rec->setFillStyle();
         return this->INHERITED::filterPath(dst, src, rec, cullRect);
     }
     return false;
 }
@@ skipping 119 matching lines @@
 
 
 #ifndef SK_IGNORE_TO_STRING
 void SkPath1DPathEffect::toString(SkString* str) const {
     str->appendf("SkPath1DPathEffect: (");
     // TODO: add path and style
     str->appendf("advance: %.2f phase %.2f", fAdvance, fInitialOffset);
     str->appendf(")");
 }
 #endif
+
+///////////////////////////////////////////////////////////////////////////////////////////////////
+
+SkPathEffect* SkPath1DPathEffect::Create(const SkPath& path, SkScalar advance, SkScalar phase,
+                                         Style style) {
+    if (advance <= 0 || path.isEmpty()) {
+        return nullptr;
+    }
+    return new SkPath1DPathEffect(path, advance, phase, style);
+}