diff --git a/ChangeLog b/ChangeLog index 6571f50d8..7bfe06673 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2009-12-07 Richard Frith-Macdonald + + * Source/GSString.m: Use -hash from GSString rather than from NSString + to optimise hashing. Fix string comparison error as pointed out by + Doug Simons. + 2009-12-02 Richard Frith-Macdonald * Source/NSMessagePortNameServer.m: diff --git a/Source/GSString.m b/Source/GSString.m index 3e0c014a5..3134ef189 100644 --- a/Source/GSString.m +++ b/Source/GSString.m @@ -302,7 +302,7 @@ setup(void) [NSStringClass instanceMethodForSelector: equalSel]; hashSel = @selector(hash); hashImp = (unsigned (*)(id, SEL)) - [NSStringClass instanceMethodForSelector: hashSel]; + [GSStringClass instanceMethodForSelector: hashSel]; caiSel = @selector(characterAtIndex:); gcrSel = @selector(getCharacters:range:); @@ -2113,7 +2113,7 @@ isEqual_c(GSStr self, id anObject) return YES; return NO; } - else if (c == GSMutableStringClass) + else if (c == GSMutableStringClass || GSObjCIsKindOf(c, GSStringClass) == YES) { GSStr other = (GSStr)anObject; NSRange r = {0, self->_count}; @@ -2144,26 +2144,6 @@ isEqual_c(GSStr self, id anObject) } return NO; } - else if (GSObjCIsKindOf(c, GSStringClass) == YES) - { - GSStr other = (GSStr)anObject; - - /* - * First see if the hash is the same - if not, we can't be equal. - */ - if (self->_flags.hash == 0) - self->_flags.hash = (*hashImp)((id)self, hashSel); - if (other->_flags.hash == 0) - other->_flags.hash = (*hashImp)((id)other, hashSel); - if (self->_flags.hash != other->_flags.hash) - return NO; - - if (other->_count == self->_count - && memcmp(other->_contents.c, self->_contents.c, self->_count) == 0) - return YES; - - return NO; - } else if (GSObjCIsKindOf(c, NSStringClass)) { return (*equalImp)((id)self, equalSel, anObject); @@ -2201,7 +2181,7 @@ isEqual_u(GSStr self, id anObject) return YES; return NO; } - else if (GSObjCIsKindOf(c, GSStringClass) == YES || c == GSMutableStringClass) + else if (c == GSMutableStringClass || GSObjCIsKindOf(c, GSStringClass) == YES) { GSStr other = (GSStr)anObject; NSRange r = {0, self->_count}; @@ -2811,12 +2791,77 @@ transmute(GSStr self, NSString *aString) setup(); } +/* + * Return a 28-bit hash value for the string contents - this + * MUST match the algorithm used by the NSString base class. + */ - (NSUInteger) hash { if (self->_flags.hash == 0) { - self->_flags.hash = (*hashImp)((id)self, hashSel); + unsigned ret = 0; + unsigned len = self->_count; + + if (len > 0) + { + register unsigned index = 0; + + if (self->_flags.wide) + { + register const char *p = self->_contents.u; + + while (index < len) + { + ret = (ret << 5) + ret + p[index++]; + } + } + else + { + register const unsigned char *p = self->_contents.c; + + if (internalEncoding == NSISOLatin1StringEncoding) + { + while (index < len) + { + ret = (ret << 5) + ret + p[index++]; + } + } + else + { + while (index < len) + { + unichar u = p[index++]; + + if (u > 127) + { + unsigned char c = (unsigned char)u; + unsigned int s = 1; + unichar *d = &u; + + GSToUnicode(&d, &s, &c, 1, internalEncoding, 0, 0); + } + ret = (ret << 5) + ret + u; + } + } + } + + /* + * The hash caching in our concrete string classes uses zero to denote + * an empty cache value, so we MUST NOT return a hash of zero. + */ + ret &= 0x0fffffff; + if (ret == 0) + { + ret = 0x0fffffff; + } + } + else + { + ret = 0x0ffffffe; /* Hash for an empty string. */ + } + self->_flags.hash = ret; } + return self->_flags.hash; } @@ -4624,7 +4669,6 @@ NSAssert(_flags.owned == 1 && _zone != 0, NSInternalInconsistencyException); return NSASCIIStringEncoding; } - /* * Return a 28-bit hash value for the string contents - this * MUST match the algorithm used by the NSString base class.