Changeset 56021 in webkit for trunk/JavaScriptCore/runtime/JSString.h

Timestamp:

Mar 15, 2010, 3:59:45 PM (15 years ago)

Author:

[email protected]

Message:

​https://bugs.webkit.org/show_bug.cgi?id=35843
Re-land reverted fix to JSString::getIndex()

Reviewed by Sam Weinig.

Calling getIndex() on a JSString in rope form may result in a JSException being thrown
if there is insuficient memory so value(exec) returns UString() with length zero,
which will be passed to jsSingleCharacterSubstring.
Add a slow case function to trap the error & return a safe null value, until the
exception is handled.

• runtime/JSString.cpp:

(JSC::JSString::getIndexSlowCase):
(JSC::JSString::getStringPropertyDescriptor):

• runtime/JSString.h:

(JSC::jsSingleCharacterSubstring):
(JSC::JSString::getIndex):
(JSC::jsSingleCharacterString):
(JSC::JSString::getStringPropertySlot):

File:

• trunk/JavaScriptCore/runtime/JSString.h (modified) (7 diffs)

trunk/JavaScriptCore/runtime/JSString.h

@@ -42 +42 @@
     JSString* jsSingleCharacterString(JSGlobalData*, UChar);
     JSString* jsSingleCharacterString(ExecState*, UChar);
-    JSString* jsSingleCharacterSubstring(JSGlobalData*, const UString&, unsigned offset);
     JSString* jsSingleCharacterSubstring(ExecState*, const UString&, unsigned offset);
     JSString* jsSubstring(JSGlobalData*, const UString&, unsigned offset, unsigned length);
@@ -241 +240 @@
         bool canGetIndex(unsigned i) { return i < m_length; }
         JSString* getIndex(ExecState*, unsigned);
+        JSString* getIndexSlowCase(ExecState*, unsigned);
 
         static PassRefPtr<Structure> createStructure(JSValue proto) { return Structure::create(proto, TypeInfo(StringType, OverridesGetOwnPropertySlot | NeedsThisConversion), AnonymousSlotCount); }
@@ -366 +366 @@
     }
 
-    inline JSString* jsSingleCharacterSubstring(JSGlobalData* globalData, const UString& s, unsigned offset)
-    {
+    inline JSString* jsSingleCharacterSubstring(ExecState* exec, const UString& s, unsigned offset)
+    {
+        JSGlobalData* globalData = &exec->globalData();
         ASSERT(offset < static_cast<unsigned>(s.size()));
         UChar c = s.data()[offset];
@@ -392 +393 @@
     {
         ASSERT(canGetIndex(i));
-        return jsSingleCharacterSubstring(&exec->globalData(), value(exec), i);
+        if (isRope())
+            return getIndexSlowCase(exec, i);
+        ASSERT(i < m_value.size());
+        return jsSingleCharacterSubstring(exec, value(exec), i);
     }
 
@@ -446 +450 @@
     inline JSString* jsString(ExecState* exec, const UString& s) { return jsString(&exec->globalData(), s); }
     inline JSString* jsSingleCharacterString(ExecState* exec, UChar c) { return jsSingleCharacterString(&exec->globalData(), c); }
-    inline JSString* jsSingleCharacterSubstring(ExecState* exec, const UString& s, unsigned offset) { return jsSingleCharacterSubstring(&exec->globalData(), s, offset); }
     inline JSString* jsSubstring(ExecState* exec, const UString& s, unsigned offset, unsigned length) { return jsSubstring(&exec->globalData(), s, offset, length); }
     inline JSString* jsNontrivialString(ExecState* exec, const UString& s) { return jsNontrivialString(&exec->globalData(), s); }
@@ -462 +465 @@
         unsigned i = propertyName.toStrictUInt32(&isStrictUInt32);
         if (isStrictUInt32 && i < m_length) {
-            slot.setValue(jsSingleCharacterSubstring(exec, value(exec), i));
+            slot.setValue(getIndex(exec, i));
             return true;
         }
@@ -472 +475 @@
     {
         if (propertyName < m_length) {
-            slot.setValue(jsSingleCharacterSubstring(exec, value(exec), propertyName));
+            slot.setValue(getIndex(exec, propertyName));
             return true;
         }