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-rw-r--r--objectivec/GPBCodedInputStream.m801
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diff --git a/objectivec/GPBCodedInputStream.m b/objectivec/GPBCodedInputStream.m
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+++ b/objectivec/GPBCodedInputStream.m
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+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc. All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#import "GPBCodedInputStream_PackagePrivate.h"
+
+#import "GPBDictionary_PackagePrivate.h"
+#import "GPBMessage_PackagePrivate.h"
+#import "GPBUnknownFieldSet_PackagePrivate.h"
+#import "GPBUtilities_PackagePrivate.h"
+#import "GPBWireFormat.h"
+
+static const NSUInteger kDefaultRecursionLimit = 64;
+
+static inline void CheckSize(GPBCodedInputStreamState *state, size_t size) {
+ size_t newSize = state->bufferPos + size;
+ if (newSize > state->bufferSize) {
+ [NSException raise:NSParseErrorException format:@""];
+ }
+ if (newSize > state->currentLimit) {
+ // Fast forward to end of currentLimit;
+ state->bufferPos = state->currentLimit;
+ [NSException raise:NSParseErrorException format:@""];
+ }
+}
+
+static inline int8_t ReadRawByte(GPBCodedInputStreamState *state) {
+ CheckSize(state, sizeof(int8_t));
+ return ((int8_t *)state->bytes)[state->bufferPos++];
+}
+
+static inline int32_t ReadRawLittleEndian32(GPBCodedInputStreamState *state) {
+ CheckSize(state, sizeof(int32_t));
+ int32_t value = OSReadLittleInt32(state->bytes, state->bufferPos);
+ state->bufferPos += sizeof(int32_t);
+ return value;
+}
+
+static inline int64_t ReadRawLittleEndian64(GPBCodedInputStreamState *state) {
+ CheckSize(state, sizeof(int64_t));
+ int64_t value = OSReadLittleInt64(state->bytes, state->bufferPos);
+ state->bufferPos += sizeof(int64_t);
+ return value;
+}
+
+static inline int32_t ReadRawVarint32(GPBCodedInputStreamState *state) {
+ int8_t tmp = ReadRawByte(state);
+ if (tmp >= 0) {
+ return tmp;
+ }
+ int32_t result = tmp & 0x7f;
+ if ((tmp = ReadRawByte(state)) >= 0) {
+ result |= tmp << 7;
+ } else {
+ result |= (tmp & 0x7f) << 7;
+ if ((tmp = ReadRawByte(state)) >= 0) {
+ result |= tmp << 14;
+ } else {
+ result |= (tmp & 0x7f) << 14;
+ if ((tmp = ReadRawByte(state)) >= 0) {
+ result |= tmp << 21;
+ } else {
+ result |= (tmp & 0x7f) << 21;
+ result |= (tmp = ReadRawByte(state)) << 28;
+ if (tmp < 0) {
+ // Discard upper 32 bits.
+ for (int i = 0; i < 5; i++) {
+ if (ReadRawByte(state) >= 0) {
+ return result;
+ }
+ }
+ [NSException raise:NSParseErrorException
+ format:@"Unable to read varint32"];
+ }
+ }
+ }
+ }
+ return result;
+}
+
+static inline int64_t ReadRawVarint64(GPBCodedInputStreamState *state) {
+ int32_t shift = 0;
+ int64_t result = 0;
+ while (shift < 64) {
+ int8_t b = ReadRawByte(state);
+ result |= (int64_t)(b & 0x7F) << shift;
+ if ((b & 0x80) == 0) {
+ return result;
+ }
+ shift += 7;
+ }
+ [NSException raise:NSParseErrorException format:@"Unable to read varint64"];
+ return 0;
+}
+
+static inline void SkipRawData(GPBCodedInputStreamState *state, size_t size) {
+ CheckSize(state, size);
+ state->bufferPos += size;
+}
+
+double GPBCodedInputStreamReadDouble(GPBCodedInputStreamState *state) {
+ int64_t value = ReadRawLittleEndian64(state);
+ return GPBConvertInt64ToDouble(value);
+}
+
+float GPBCodedInputStreamReadFloat(GPBCodedInputStreamState *state) {
+ int32_t value = ReadRawLittleEndian32(state);
+ return GPBConvertInt32ToFloat(value);
+}
+
+uint64_t GPBCodedInputStreamReadUInt64(GPBCodedInputStreamState *state) {
+ uint64_t value = ReadRawVarint64(state);
+ return value;
+}
+
+uint32_t GPBCodedInputStreamReadUInt32(GPBCodedInputStreamState *state) {
+ uint32_t value = ReadRawVarint32(state);
+ return value;
+}
+
+int64_t GPBCodedInputStreamReadInt64(GPBCodedInputStreamState *state) {
+ int64_t value = ReadRawVarint64(state);
+ return value;
+}
+
+int32_t GPBCodedInputStreamReadInt32(GPBCodedInputStreamState *state) {
+ int32_t value = ReadRawVarint32(state);
+ return value;
+}
+
+uint64_t GPBCodedInputStreamReadFixed64(GPBCodedInputStreamState *state) {
+ uint64_t value = ReadRawLittleEndian64(state);
+ return value;
+}
+
+uint32_t GPBCodedInputStreamReadFixed32(GPBCodedInputStreamState *state) {
+ uint32_t value = ReadRawLittleEndian32(state);
+ return value;
+}
+
+int32_t GPBCodedInputStreamReadEnum(GPBCodedInputStreamState *state) {
+ int32_t value = ReadRawVarint32(state);
+ return value;
+}
+
+int32_t GPBCodedInputStreamReadSFixed32(GPBCodedInputStreamState *state) {
+ int32_t value = ReadRawLittleEndian32(state);
+ return value;
+}
+
+int64_t GPBCodedInputStreamReadSFixed64(GPBCodedInputStreamState *state) {
+ int64_t value = ReadRawLittleEndian64(state);
+ return value;
+}
+
+int32_t GPBCodedInputStreamReadSInt32(GPBCodedInputStreamState *state) {
+ int32_t value = GPBDecodeZigZag32(ReadRawVarint32(state));
+ return value;
+}
+
+int64_t GPBCodedInputStreamReadSInt64(GPBCodedInputStreamState *state) {
+ int64_t value = GPBDecodeZigZag64(ReadRawVarint64(state));
+ return value;
+}
+
+BOOL GPBCodedInputStreamReadBool(GPBCodedInputStreamState *state) {
+ return ReadRawVarint32(state) != 0;
+}
+
+int32_t GPBCodedInputStreamReadTag(GPBCodedInputStreamState *state) {
+ if (GPBCodedInputStreamIsAtEnd(state)) {
+ state->lastTag = 0;
+ return 0;
+ }
+
+ state->lastTag = ReadRawVarint32(state);
+ if (state->lastTag == 0) {
+ // If we actually read zero, that's not a valid tag.
+ [NSException raise:NSParseErrorException
+ format:@"Invalid last tag %d", state->lastTag];
+ }
+ return state->lastTag;
+}
+
+NSString *GPBCodedInputStreamReadRetainedString(
+ GPBCodedInputStreamState *state) {
+ int32_t size = ReadRawVarint32(state);
+ NSString *result;
+ if (size == 0) {
+ result = @"";
+ } else {
+ CheckSize(state, size);
+ result = GPBCreateGPBStringWithUTF8(&state->bytes[state->bufferPos], size);
+ state->bufferPos += size;
+ }
+ return result;
+}
+
+NSData *GPBCodedInputStreamReadRetainedData(GPBCodedInputStreamState *state) {
+ int32_t size = ReadRawVarint32(state);
+ if (size < 0) return nil;
+ CheckSize(state, size);
+ NSData *result = [[NSData alloc] initWithBytes:state->bytes + state->bufferPos
+ length:size];
+ state->bufferPos += size;
+ return result;
+}
+
+NSData *GPBCodedInputStreamReadRetainedDataNoCopy(
+ GPBCodedInputStreamState *state) {
+ int32_t size = ReadRawVarint32(state);
+ if (size < 0) return nil;
+ CheckSize(state, size);
+ // Cast is safe because freeWhenDone is NO.
+ NSData *result = [[NSData alloc]
+ initWithBytesNoCopy:(void *)(state->bytes + state->bufferPos)
+ length:size
+ freeWhenDone:NO];
+ state->bufferPos += size;
+ return result;
+}
+
+size_t GPBCodedInputStreamPushLimit(GPBCodedInputStreamState *state,
+ size_t byteLimit) {
+ byteLimit += state->bufferPos;
+ size_t oldLimit = state->currentLimit;
+ if (byteLimit > oldLimit) {
+ [NSException raise:NSInvalidArgumentException
+ format:@"byteLimit > oldLimit: %tu > %tu", byteLimit, oldLimit];
+ }
+ state->currentLimit = byteLimit;
+ return oldLimit;
+}
+
+void GPBCodedInputStreamPopLimit(GPBCodedInputStreamState *state,
+ size_t oldLimit) {
+ state->currentLimit = oldLimit;
+}
+
+size_t GPBCodedInputStreamBytesUntilLimit(GPBCodedInputStreamState *state) {
+ if (state->currentLimit == SIZE_T_MAX) {
+ return state->currentLimit;
+ }
+
+ return state->currentLimit - state->bufferPos;
+}
+
+BOOL GPBCodedInputStreamIsAtEnd(GPBCodedInputStreamState *state) {
+ return (state->bufferPos == state->bufferSize) ||
+ (state->bufferPos == state->currentLimit);
+}
+
+void GPBCodedInputStreamCheckLastTagWas(GPBCodedInputStreamState *state,
+ int32_t value) {
+ if (state->lastTag != value) {
+ [NSException raise:NSParseErrorException
+ format:@"Last tag: %d should be %d", state->lastTag, value];
+ }
+}
+
+@implementation GPBCodedInputStream
+
++ (instancetype)streamWithData:(NSData *)data {
+ return [[[self alloc] initWithData:data] autorelease];
+}
+
+- (instancetype)initWithData:(NSData *)data {
+ if ((self = [super init])) {
+#ifdef DEBUG
+ NSCAssert([self class] == [GPBCodedInputStream class],
+ @"Subclassing of GPBCodedInputStream is not allowed.");
+#endif
+ buffer_ = [data retain];
+ state_.bytes = (const uint8_t *)[data bytes];
+ state_.bufferSize = [data length];
+ state_.currentLimit = NSUIntegerMax;
+ }
+ return self;
+}
+
+- (void)dealloc {
+ [buffer_ release];
+ [super dealloc];
+}
+
+- (int32_t)readTag {
+ return GPBCodedInputStreamReadTag(&state_);
+}
+
+- (void)checkLastTagWas:(int32_t)value {
+ GPBCodedInputStreamCheckLastTagWas(&state_, value);
+}
+
+- (BOOL)skipField:(int32_t)tag {
+ switch (GPBWireFormatGetTagWireType(tag)) {
+ case GPBWireFormatVarint:
+ GPBCodedInputStreamReadInt32(&state_);
+ return YES;
+ case GPBWireFormatFixed64:
+ SkipRawData(&state_, sizeof(int64_t));
+ return YES;
+ case GPBWireFormatLengthDelimited:
+ SkipRawData(&state_, ReadRawVarint32(&state_));
+ return YES;
+ case GPBWireFormatStartGroup:
+ [self skipMessage];
+ GPBCodedInputStreamCheckLastTagWas(
+ &state_, GPBWireFormatMakeTag(GPBWireFormatGetTagFieldNumber(tag),
+ GPBWireFormatEndGroup));
+ return YES;
+ case GPBWireFormatEndGroup:
+ return NO;
+ case GPBWireFormatFixed32:
+ SkipRawData(&state_, sizeof(int32_t));
+ return YES;
+ }
+ [NSException raise:NSParseErrorException format:@"Invalid tag %d", tag];
+ return NO;
+}
+
+- (void)skipMessage {
+ while (YES) {
+ int32_t tag = GPBCodedInputStreamReadTag(&state_);
+ if (tag == 0 || ![self skipField:tag]) {
+ return;
+ }
+ }
+}
+
+- (double)readDouble {
+ return GPBCodedInputStreamReadDouble(&state_);
+}
+
+- (float)readFloat {
+ return GPBCodedInputStreamReadFloat(&state_);
+}
+
+- (uint64_t)readUInt64 {
+ return GPBCodedInputStreamReadUInt64(&state_);
+}
+
+- (int64_t)readInt64 {
+ return GPBCodedInputStreamReadInt64(&state_);
+}
+
+- (int32_t)readInt32 {
+ return GPBCodedInputStreamReadInt32(&state_);
+}
+
+- (uint64_t)readFixed64 {
+ return GPBCodedInputStreamReadFixed64(&state_);
+}
+
+- (uint32_t)readFixed32 {
+ return GPBCodedInputStreamReadFixed32(&state_);
+}
+
+- (BOOL)readBool {
+ return GPBCodedInputStreamReadBool(&state_);
+}
+
+- (NSString *)readString {
+ return [GPBCodedInputStreamReadRetainedString(&state_) autorelease];
+}
+
+- (void)readGroup:(int32_t)fieldNumber
+ message:(GPBMessage *)message
+ extensionRegistry:(GPBExtensionRegistry *)extensionRegistry {
+ if (state_.recursionDepth >= kDefaultRecursionLimit) {
+ [NSException raise:NSParseErrorException
+ format:@"recursionDepth(%tu) >= %tu", state_.recursionDepth,
+ kDefaultRecursionLimit];
+ }
+ ++state_.recursionDepth;
+ [message mergeFromCodedInputStream:self extensionRegistry:extensionRegistry];
+ GPBCodedInputStreamCheckLastTagWas(
+ &state_, GPBWireFormatMakeTag(fieldNumber, GPBWireFormatEndGroup));
+ --state_.recursionDepth;
+}
+
+- (void)readUnknownGroup:(int32_t)fieldNumber
+ message:(GPBUnknownFieldSet *)message {
+ if (state_.recursionDepth >= kDefaultRecursionLimit) {
+ [NSException raise:NSParseErrorException
+ format:@"recursionDepth(%tu) >= %tu", state_.recursionDepth,
+ kDefaultRecursionLimit];
+ }
+ ++state_.recursionDepth;
+ [message mergeFromCodedInputStream:self];
+ GPBCodedInputStreamCheckLastTagWas(
+ &state_, GPBWireFormatMakeTag(fieldNumber, GPBWireFormatEndGroup));
+ --state_.recursionDepth;
+}
+
+- (void)readMessage:(GPBMessage *)message
+ extensionRegistry:(GPBExtensionRegistry *)extensionRegistry {
+ int32_t length = ReadRawVarint32(&state_);
+ if (state_.recursionDepth >= kDefaultRecursionLimit) {
+ [NSException raise:NSParseErrorException
+ format:@"recursionDepth(%tu) >= %tu", state_.recursionDepth,
+ kDefaultRecursionLimit];
+ }
+ size_t oldLimit = GPBCodedInputStreamPushLimit(&state_, length);
+ ++state_.recursionDepth;
+ [message mergeFromCodedInputStream:self extensionRegistry:extensionRegistry];
+ GPBCodedInputStreamCheckLastTagWas(&state_, 0);
+ --state_.recursionDepth;
+ GPBCodedInputStreamPopLimit(&state_, oldLimit);
+}
+
+- (void)readMapEntry:(id)mapDictionary
+ extensionRegistry:(GPBExtensionRegistry *)extensionRegistry
+ field:(GPBFieldDescriptor *)field
+ parentMessage:(GPBMessage *)parentMessage {
+ int32_t length = ReadRawVarint32(&state_);
+ if (state_.recursionDepth >= kDefaultRecursionLimit) {
+ [NSException raise:NSParseErrorException
+ format:@"recursionDepth(%tu) >= %tu", state_.recursionDepth,
+ kDefaultRecursionLimit];
+ }
+ size_t oldLimit = GPBCodedInputStreamPushLimit(&state_, length);
+ ++state_.recursionDepth;
+ GPBDictionaryReadEntry(mapDictionary, self, extensionRegistry, field,
+ parentMessage);
+ GPBCodedInputStreamCheckLastTagWas(&state_, 0);
+ --state_.recursionDepth;
+ GPBCodedInputStreamPopLimit(&state_, oldLimit);
+}
+
+- (NSData *)readData {
+ return [GPBCodedInputStreamReadRetainedData(&state_) autorelease];
+}
+
+- (uint32_t)readUInt32 {
+ return GPBCodedInputStreamReadUInt32(&state_);
+}
+
+- (int32_t)readEnum {
+ return GPBCodedInputStreamReadEnum(&state_);
+}
+
+- (int32_t)readSFixed32 {
+ return GPBCodedInputStreamReadSFixed32(&state_);
+}
+
+- (int64_t)readSFixed64 {
+ return GPBCodedInputStreamReadSFixed64(&state_);
+}
+
+- (int32_t)readSInt32 {
+ return GPBCodedInputStreamReadSInt32(&state_);
+}
+
+- (int64_t)readSInt64 {
+ return GPBCodedInputStreamReadSInt64(&state_);
+}
+
+@end
+
+@implementation GPBString {
+ @package
+ CFStringRef string_;
+ unsigned char *utf8_;
+ NSUInteger utf8Len_;
+
+ // This lock is used to gate access to utf8_. Once GPBStringInitStringValue()
+ // has been called, string_ will be filled in, and utf8_ will be NULL.
+ OSSpinLock lock_;
+
+ BOOL hasBOM_;
+ BOOL is7BitAscii_;
+}
+
+// Returns true if the passed in bytes are 7 bit ascii.
+// This routine needs to be fast.
+static inline bool AreBytesIn7BitASCII(const uint8_t *bytes, NSUInteger len) {
+// In the loops below, it's more efficient to collect rather than do
+// conditional at every step.
+#if __LP64__
+ // Align bytes. This is especially important in case of 3 byte BOM.
+ while (len > 0 && ((size_t)bytes & 0x07)) {
+ if (*bytes++ & 0x80) return false;
+ len--;
+ }
+ while (len >= 32) {
+ uint64_t val = *(const uint64_t *)bytes;
+ uint64_t hiBits = (val & 0x8080808080808080ULL);
+ bytes += 8;
+ val = *(const uint64_t *)bytes;
+ hiBits |= (val & 0x8080808080808080ULL);
+ bytes += 8;
+ val = *(const uint64_t *)bytes;
+ hiBits |= (val & 0x8080808080808080ULL);
+ bytes += 8;
+ val = *(const uint64_t *)bytes;
+ if (hiBits | (val & 0x8080808080808080ULL)) return false;
+ bytes += 8;
+ len -= 32;
+ }
+
+ while (len >= 16) {
+ uint64_t val = *(const uint64_t *)bytes;
+ uint64_t hiBits = (val & 0x8080808080808080ULL);
+ bytes += 8;
+ val = *(const uint64_t *)bytes;
+ if (hiBits | (val & 0x8080808080808080ULL)) return false;
+ bytes += 8;
+ len -= 16;
+ }
+
+ while (len >= 8) {
+ uint64_t val = *(const uint64_t *)bytes;
+ if (val & 0x8080808080808080ULL) return false;
+ bytes += 8;
+ len -= 8;
+ }
+#else // __LP64__
+ // Align bytes. This is especially important in case of 3 byte BOM.
+ while (len > 0 && ((size_t)bytes & 0x03)) {
+ if (*bytes++ & 0x80) return false;
+ len--;
+ }
+ while (len >= 16) {
+ uint32_t val = *(const uint32_t *)bytes;
+ uint32_t hiBits = (val & 0x80808080U);
+ bytes += 4;
+ val = *(const uint32_t *)bytes;
+ hiBits |= (val & 0x80808080U);
+ bytes += 4;
+ val = *(const uint32_t *)bytes;
+ hiBits |= (val & 0x80808080U);
+ bytes += 4;
+ val = *(const uint32_t *)bytes;
+ if (hiBits | (val & 0x80808080U)) return false;
+ bytes += 4;
+ len -= 16;
+ }
+
+ while (len >= 8) {
+ uint32_t val = *(const uint32_t *)bytes;
+ uint32_t hiBits = (val & 0x80808080U);
+ bytes += 4;
+ val = *(const uint32_t *)bytes;
+ if (hiBits | (val & 0x80808080U)) return false;
+ bytes += 4;
+ len -= 8;
+ }
+#endif // __LP64__
+
+ while (len >= 4) {
+ uint32_t val = *(const uint32_t *)bytes;
+ if (val & 0x80808080U) return false;
+ bytes += 4;
+ len -= 4;
+ }
+
+ while (len--) {
+ if (*bytes++ & 0x80) return false;
+ }
+
+ return true;
+}
+
+static inline void GPBStringInitStringValue(GPBString *string) {
+ OSSpinLockLock(&string->lock_);
+ GPBStringInitStringValueAlreadyLocked(string);
+ OSSpinLockUnlock(&string->lock_);
+}
+
+static void GPBStringInitStringValueAlreadyLocked(GPBString *string) {
+ if (string->string_ == NULL && string->utf8_ != NULL) {
+ // Using kCFAllocatorMalloc for contentsDeallocator, as buffer in
+ // string->utf8_ is being handed off.
+ string->string_ = CFStringCreateWithBytesNoCopy(
+ NULL, string->utf8_, string->utf8Len_, kCFStringEncodingUTF8, false,
+ kCFAllocatorMalloc);
+ if (!string->string_) {
+#ifdef DEBUG
+ // https://developers.google.com/protocol-buffers/docs/proto#scalar
+ NSLog(@"UTF8 failure, is some field type 'string' when it should be "
+ @"'bytes'?");
+#endif
+ string->string_ = CFSTR("");
+ string->utf8Len_ = 0;
+ // On failure, we have to clean up the buffer.
+ free(string->utf8_);
+ }
+ string->utf8_ = NULL;
+ }
+}
+
+GPBString *GPBCreateGPBStringWithUTF8(const void *bytes, NSUInteger length) {
+ GPBString *result = [[GPBString alloc] initWithBytes:bytes length:length];
+ return result;
+}
+
+- (instancetype)initWithBytes:(const void *)bytes length:(NSUInteger)length {
+ self = [super init];
+ if (self) {
+ utf8_ = malloc(length);
+ memcpy(utf8_, bytes, length);
+ utf8Len_ = length;
+ lock_ = OS_SPINLOCK_INIT;
+ is7BitAscii_ = AreBytesIn7BitASCII(bytes, length);
+ if (length >= 3 && memcmp(utf8_, "\xef\xbb\xbf", 3) == 0) {
+ // We can't just remove the BOM from the string here, because in the case
+ // where we have > 1 BOM at the beginning of the string, we will remove one,
+ // and the internal NSString we create will remove the next one, and we will
+ // end up with a GPBString != NSString issue.
+ // We also just can't remove all the BOMs because then we would end up with
+ // potential cases where a GPBString and an NSString made with the same
+ // UTF8 buffer would in fact be different.
+ // We record the fact we have a BOM, and use it as necessary to simulate
+ // what NSString would return for various calls.
+ hasBOM_ = YES;
+#if DEBUG
+ // Sending BOMs across the line is just wasting bits.
+ NSLog(@"Bad data? String should not have BOM!");
+#endif // DEBUG
+ }
+ }
+ return self;
+}
+
+- (void)dealloc {
+ if (string_ != NULL) {
+ CFRelease(string_);
+ }
+ if (utf8_ != NULL) {
+ free(utf8_);
+ }
+ [super dealloc];
+}
+
+// Required NSString overrides.
+- (NSUInteger)length {
+ if (is7BitAscii_) {
+ return utf8Len_;
+ } else {
+ GPBStringInitStringValue(self);
+ return CFStringGetLength(string_);
+ }
+}
+
+- (unichar)characterAtIndex:(NSUInteger)anIndex {
+ OSSpinLockLock(&lock_);
+ if (is7BitAscii_ && utf8_) {
+ unichar result = utf8_[anIndex];
+ OSSpinLockUnlock(&lock_);
+ return result;
+ } else {
+ GPBStringInitStringValueAlreadyLocked(self);
+ OSSpinLockUnlock(&lock_);
+ return CFStringGetCharacterAtIndex(string_, anIndex);
+ }
+}
+
+// Override a couple of methods that typically want high performance.
+
+- (id)copyWithZone:(NSZone *)zone {
+ GPBStringInitStringValue(self);
+ return [(NSString *)string_ copyWithZone:zone];
+}
+
+- (id)mutableCopyWithZone:(NSZone *)zone {
+ GPBStringInitStringValue(self);
+ return [(NSString *)string_ mutableCopyWithZone:zone];
+}
+
+- (NSUInteger)hash {
+ // Must convert to string here to make sure that the hash is always
+ // consistent no matter what state the GPBString is in.
+ GPBStringInitStringValue(self);
+ return CFHash(string_);
+}
+
+- (BOOL)isEqual:(id)object {
+ if (self == object) {
+ return YES;
+ }
+ if ([object isKindOfClass:[NSString class]]) {
+ GPBStringInitStringValue(self);
+ return CFStringCompare(string_, (CFStringRef)object, 0) ==
+ kCFCompareEqualTo;
+ }
+ return NO;
+}
+
+- (void)getCharacters:(unichar *)buffer range:(NSRange)aRange {
+ OSSpinLockLock(&lock_);
+ if (is7BitAscii_ && utf8_) {
+ unsigned char *bytes = &(utf8_[aRange.location]);
+ for (NSUInteger i = 0; i < aRange.length; ++i) {
+ buffer[i] = bytes[i];
+ }
+ OSSpinLockUnlock(&lock_);
+ } else {
+ GPBStringInitStringValueAlreadyLocked(self);
+ OSSpinLockUnlock(&lock_);
+ CFStringGetCharacters(string_, CFRangeMake(aRange.location, aRange.length),
+ buffer);
+ }
+}
+
+- (NSUInteger)lengthOfBytesUsingEncoding:(NSStringEncoding)encoding {
+ if ((encoding == NSUTF8StringEncoding) ||
+ (encoding == NSASCIIStringEncoding && is7BitAscii_)) {
+ return utf8Len_ - (hasBOM_ ? 3 : 0);
+ } else {
+ GPBStringInitStringValue(self);
+ return [(NSString *)string_ lengthOfBytesUsingEncoding:encoding];
+ }
+}
+
+- (BOOL)getBytes:(void *)buffer
+ maxLength:(NSUInteger)maxLength
+ usedLength:(NSUInteger *)usedLength
+ encoding:(NSStringEncoding)encoding
+ options:(NSStringEncodingConversionOptions)options
+ range:(NSRange)range
+ remainingRange:(NSRangePointer)remainingRange {
+ // [NSString getBytes:maxLength:usedLength:encoding:options:range:remainingRange]
+ // does not return reliable results if the maxLength argument is 0
+ // (Radar 16385183). Therefore we have special cased it as a slow case so
+ // that it behaves however Apple intends it to behave. It should be a rare
+ // case.
+ //
+ // [NSString getBytes:maxLength:usedLength:encoding:options:range:remainingRange]
+ // does not return reliable results if the range is outside of the strings
+ // length (Radar 16396177). Therefore we have special cased it as a slow
+ // case so that it behaves however Apple intends it to behave. It should
+ // be a rare case.
+ //
+ // We can optimize the UTF8StringEncoding and NSASCIIStringEncoding with no
+ // options cases.
+ if ((options == 0) &&
+ (encoding == NSUTF8StringEncoding || encoding == NSASCIIStringEncoding) &&
+ (maxLength != 0) &&
+ (NSMaxRange(range) <= utf8Len_)) {
+ // Might be able to optimize it.
+ OSSpinLockLock(&lock_);
+ if (is7BitAscii_ && utf8_) {
+ NSUInteger length = range.length;
+ length = (length < maxLength) ? length : maxLength;
+ memcpy(buffer, utf8_ + range.location, length);
+ if (usedLength) {
+ *usedLength = length;
+ }
+ if (remainingRange) {
+ remainingRange->location = range.location + length;
+ remainingRange->length = range.length - length;
+ }
+ OSSpinLockUnlock(&lock_);
+ if (length > 0) {
+ return YES;
+ } else {
+ return NO;
+ }
+ } else {
+ GPBStringInitStringValueAlreadyLocked(self);
+ OSSpinLockUnlock(&lock_);
+ }
+ } else {
+ GPBStringInitStringValue(self);
+ }
+ return [(NSString *)string_ getBytes:buffer
+ maxLength:maxLength
+ usedLength:usedLength
+ encoding:encoding
+ options:options
+ range:range
+ remainingRange:remainingRange];
+}
+
+@end