Changeset 162205 in webkit for trunk/Source/JavaScriptCore/API/JSStringRefCF.cpp

Timestamp:

Jan 17, 2014, 9:44:49 AM (11 years ago)

Author:

[email protected]

Message:

Get rid of OpaqueJSString::deprecatedCharacters()
​https://bugs.webkit.org/show_bug.cgi?id=127161

Reviewed by Sam Weinig.

Handle OpaqueJSString::m_string being either 8-bit or 16-bit and add extra
code paths for the 8-bit cases.

Unfortunately, JSStringGetCharactersPtr is still expected to return a 16-bit character pointer.
Handle this by storing a separate 16-bit string and initializing it on demand when JSStringGetCharactersPtr
is called and the backing string is 8-bit.

This has the nice side effect of making JSStringGetCharactersPtr thread-safe when it wasn't before.
(In theory, someone could have a JSStringRef backed by an 8-bit string and call JSStringGetCharactersPtr on it
causing an unsafe upconversion to a 16-bit string).

• API/JSStringRef.cpp:

(JSStringGetCharactersPtr):
Call OpaqueJSString::characters.

(JSStringGetUTF8CString):
Add a code path that handles 8-bit strings.

(JSStringIsEqual):
Call OpaqueJSString::equal.

• API/JSStringRefCF.cpp:

(JSStringCreateWithCFString):
Reformat the code to use an early return instead of putting most of the code inside the body of an if statement.

(JSStringCopyCFString):
Create an 8-bit CFStringRef if possible.

• API/OpaqueJSString.cpp:

(OpaqueJSString::create):
Use nullptr.

(OpaqueJSString::~OpaqueJSString):
Free m_characters.

(OpaqueJSString::characters):
Do the up-conversion and store the result in m_characters.

(OpaqueJSString::equal):
New helper function.

• API/OpaqueJSString.h:

(OpaqueJSString::is8Bit):
New function that returns whether a string is 8-bit or not.

(OpaqueJSString::characters8):
(OpaqueJSString::characters16):
Add getters.

File:

• trunk/Source/JavaScriptCore/API/JSStringRefCF.cpp (modified) (1 diff)

trunk/Source/JavaScriptCore/API/JSStringRefCF.cpp

@@ -41 +41 @@
     // it can hold.  (<rdar://problem/6806478>)
     size_t length = CFStringGetLength(string);
-    if (length) {
-        Vector<LChar, 1024> lcharBuffer(length);
-        CFIndex usedBufferLength;
-        CFIndex convertedSize = CFStringGetBytes(string, CFRangeMake(0, length), kCFStringEncodingISOLatin1, 0, false, lcharBuffer.data(), length, &usedBufferLength);
-        if (static_cast<size_t>(convertedSize) == length && static_cast<size_t>(usedBufferLength) == length)
-            return OpaqueJSString::create(lcharBuffer.data(), length).leakRef();
+    if (!length)
+        return OpaqueJSString::create(reinterpret_cast<const LChar*>(""), 0).leakRef();
 
-        auto buffer = std::make_unique<UniChar[]>(length);
-        CFStringGetCharacters(string, CFRangeMake(0, length), buffer.get());
-        COMPILE_ASSERT(sizeof(UniChar) == sizeof(UChar), unichar_and_uchar_must_be_same_size);
-        return OpaqueJSString::create(reinterpret_cast<UChar*>(buffer.get()), length).leakRef();
-    }
-    
-    return OpaqueJSString::create(reinterpret_cast<const LChar*>(""), 0).leakRef();
+    Vector<LChar, 1024> lcharBuffer(length);
+    CFIndex usedBufferLength;
+    CFIndex convertedSize = CFStringGetBytes(string, CFRangeMake(0, length), kCFStringEncodingISOLatin1, 0, false, lcharBuffer.data(), length, &usedBufferLength);
+    if (static_cast<size_t>(convertedSize) == length && static_cast<size_t>(usedBufferLength) == length)
+        return OpaqueJSString::create(lcharBuffer.data(), length).leakRef();
+
+    auto buffer = std::make_unique<UniChar[]>(length);
+    CFStringGetCharacters(string, CFRangeMake(0, length), buffer.get());
+    static_assert(sizeof(UniChar) == sizeof(UChar), "UniChar and UChar must be same size");
+    return OpaqueJSString::create(reinterpret_cast<UChar*>(buffer.get()), length).leakRef();
 }
 
-CFStringRef JSStringCopyCFString(CFAllocatorRef alloc, JSStringRef string)
+CFStringRef JSStringCopyCFString(CFAllocatorRef allocator, JSStringRef string)
 {
     if (!string->length())
         return CFSTR("");
 
-    return CFStringCreateWithCharacters(alloc, reinterpret_cast<const UniChar*>(string->deprecatedCharacters()), string->length());
+    if (string->is8Bit())
+        return CFStringCreateWithBytes(allocator, reinterpret_cast<const UInt8*>(string->characters8()), string->length(), kCFStringEncodingISOLatin1, false);
+
+    return CFStringCreateWithCharacters(allocator, reinterpret_cast<const UniChar*>(string->characters16()), string->length());
 }