NetNewsWire/Frameworks/RSParser/SAX/RSSAXParser.m
2017-10-04 13:28:48 -07:00

347 lines
8.9 KiB
Objective-C
Executable File

//
// RSSAXParser.m
// RSParser
//
// Created by Brent Simmons on 3/25/15.
// Copyright (c) 2015 Ranchero Software, LLC. All rights reserved.
//
#import <libxml/tree.h>
#import <libxml/xmlstring.h>
#import <RSParser/RSSAXParser.h>
#import <RSParser/RSParserInternal.h>
@interface RSSAXParser ()
@property (nonatomic, weak) id<RSSAXParserDelegate> delegate;
@property (nonatomic, assign) xmlParserCtxtPtr context;
@property (nonatomic, assign) BOOL storingCharacters;
@property (nonatomic) NSMutableData *characters;
@property (nonatomic) BOOL delegateRespondsToInternedStringMethod;
@property (nonatomic) BOOL delegateRespondsToInternedStringForValueMethod;
@property (nonatomic) BOOL delegateRespondsToStartElementMethod;
@property (nonatomic) BOOL delegateRespondsToEndElementMethod;
@property (nonatomic) BOOL delegateRespondsToCharactersFoundMethod;
@property (nonatomic) BOOL delegateRespondsToEndOfDocumentMethod;
@end
@implementation RSSAXParser
+ (void)initialize {
RSSAXInitLibXMLParser();
}
#pragma mark - Init
- (instancetype)initWithDelegate:(id<RSSAXParserDelegate>)delegate {
self = [super init];
if (self == nil)
return nil;
_delegate = delegate;
if ([_delegate respondsToSelector:@selector(saxParser:internedStringForName:prefix:)]) {
_delegateRespondsToInternedStringMethod = YES;
}
if ([_delegate respondsToSelector:@selector(saxParser:internedStringForValue:length:)]) {
_delegateRespondsToInternedStringForValueMethod = YES;
}
if ([_delegate respondsToSelector:@selector(saxParser:XMLStartElement:prefix:uri:numberOfNamespaces:namespaces:numberOfAttributes:numberDefaulted:attributes:)]) {
_delegateRespondsToStartElementMethod = YES;
}
if ([_delegate respondsToSelector:@selector(saxParser:XMLEndElement:prefix:uri:)]) {
_delegateRespondsToEndElementMethod = YES;
}
if ([_delegate respondsToSelector:@selector(saxParser:XMLCharactersFound:length:)]) {
_delegateRespondsToCharactersFoundMethod = YES;
}
if ([_delegate respondsToSelector:@selector(saxParserDidReachEndOfDocument:)]) {
_delegateRespondsToEndOfDocumentMethod = YES;
}
return self;
}
#pragma mark - Dealloc
- (void)dealloc {
if (_context != nil) {
xmlFreeParserCtxt(_context);
_context = nil;
}
_delegate = nil;
}
#pragma mark - API
static xmlSAXHandler saxHandlerStruct;
- (void)parseData:(NSData *)data {
[self parseBytes:data.bytes numberOfBytes:data.length];
}
- (void)parseBytes:(const void *)bytes numberOfBytes:(NSUInteger)numberOfBytes {
if (self.context == nil) {
self.context = xmlCreatePushParserCtxt(&saxHandlerStruct, (__bridge void *)self, nil, 0, nil);
xmlCtxtUseOptions(self.context, XML_PARSE_RECOVER | XML_PARSE_NOENT);
}
@autoreleasepool {
xmlParseChunk(self.context, (const char *)bytes, (int)numberOfBytes, 0);
}
}
- (void)finishParsing {
NSAssert(self.context != nil, nil);
if (self.context == nil)
return;
@autoreleasepool {
xmlParseChunk(self.context, nil, 0, 1);
xmlFreeParserCtxt(self.context);
self.context = nil;
self.characters = nil;
}
}
- (void)cancel {
@autoreleasepool {
xmlStopParser(self.context);
}
}
- (void)beginStoringCharacters {
self.storingCharacters = YES;
self.characters = [NSMutableData new];
}
- (void)endStoringCharacters {
self.storingCharacters = NO;
self.characters = nil;
}
- (NSData *)currentCharacters {
if (!self.storingCharacters) {
return nil;
}
return self.characters;
}
- (NSString *)currentString {
NSData *d = self.currentCharacters;
if (RSParserObjectIsEmpty(d)) {
return nil;
}
return [[NSString alloc] initWithData:d encoding:NSUTF8StringEncoding];
}
- (NSString *)currentStringWithTrimmedWhitespace {
return [self.currentString stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
}
#pragma mark - Attributes Dictionary
- (NSDictionary *)attributesDictionary:(const xmlChar **)attributes numberOfAttributes:(NSInteger)numberOfAttributes {
if (numberOfAttributes < 1 || !attributes) {
return nil;
}
NSMutableDictionary *d = [NSMutableDictionary new];
@autoreleasepool {
NSInteger i = 0, j = 0;
for (i = 0, j = 0; i < numberOfAttributes; i++, j+=5) {
NSUInteger lenValue = (NSUInteger)(attributes[j + 4] - attributes[j + 3]);
NSString *value = nil;
if (self.delegateRespondsToInternedStringForValueMethod) {
value = [self.delegate saxParser:self internedStringForValue:(const void *)attributes[j + 3] length:lenValue];
}
if (!value) {
value = [[NSString alloc] initWithBytes:(const void *)attributes[j + 3] length:lenValue encoding:NSUTF8StringEncoding];
}
NSString *attributeName = nil;
if (self.delegateRespondsToInternedStringMethod) {
attributeName = [self.delegate saxParser:self internedStringForName:(const xmlChar *)attributes[j] prefix:(const xmlChar *)attributes[j + 1]];
}
if (!attributeName) {
attributeName = [NSString stringWithUTF8String:(const char *)attributes[j]];
if (attributes[j + 1]) {
NSString *attributePrefix = [NSString stringWithUTF8String:(const char *)attributes[j + 1]];
attributeName = [NSString stringWithFormat:@"%@:%@", attributePrefix, attributeName];
}
}
if (value && attributeName) {
d[attributeName] = value;
}
}
}
return d;
}
#pragma mark - Equal Tags
BOOL RSSAXEqualTags(const xmlChar *localName, const char *tag, NSInteger tagLength) {
if (!localName) {
return NO;
}
return !strncmp((const char *)localName, tag, (size_t)tagLength);
}
#pragma mark - Callbacks
- (void)xmlEndDocument {
@autoreleasepool {
if (self.delegateRespondsToEndOfDocumentMethod) {
[self.delegate saxParserDidReachEndOfDocument:self];
}
[self endStoringCharacters];
}
}
- (void)xmlCharactersFound:(const xmlChar *)ch length:(NSUInteger)length {
@autoreleasepool {
if (self.storingCharacters) {
[self.characters appendBytes:(const void *)ch length:length];
}
if (self.delegateRespondsToCharactersFoundMethod) {
[self.delegate saxParser:self XMLCharactersFound:ch length:length];
}
}
}
- (void)xmlStartElement:(const xmlChar *)localName prefix:(const xmlChar *)prefix uri:(const xmlChar *)uri numberOfNamespaces:(int)numberOfNamespaces namespaces:(const xmlChar **)namespaces numberOfAttributes:(int)numberOfAttributes numberDefaulted:(int)numberDefaulted attributes:(const xmlChar **)attributes {
@autoreleasepool {
if (self.delegateRespondsToStartElementMethod) {
[self.delegate saxParser:self XMLStartElement:localName prefix:prefix uri:uri numberOfNamespaces:numberOfNamespaces namespaces:namespaces numberOfAttributes:numberOfAttributes numberDefaulted:numberDefaulted attributes:attributes];
}
}
}
- (void)xmlEndElement:(const xmlChar *)localName prefix:(const xmlChar *)prefix uri:(const xmlChar *)uri {
@autoreleasepool {
if (self.delegateRespondsToEndElementMethod) {
[self.delegate saxParser:self XMLEndElement:localName prefix:prefix uri:uri];
}
[self endStoringCharacters];
}
}
@end
static void startElementSAX(void *context, const xmlChar *localname, const xmlChar *prefix, const xmlChar *URI, int nb_namespaces, const xmlChar **namespaces, int nb_attributes, int nb_defaulted, const xmlChar **attributes) {
[(__bridge RSSAXParser *)context xmlStartElement:localname prefix:prefix uri:URI numberOfNamespaces:nb_namespaces namespaces:namespaces numberOfAttributes:nb_attributes numberDefaulted:nb_defaulted attributes:attributes];
}
static void endElementSAX(void *context, const xmlChar *localname, const xmlChar *prefix, const xmlChar *URI) {
[(__bridge RSSAXParser *)context xmlEndElement:localname prefix:prefix uri:URI];
}
static void charactersFoundSAX(void *context, const xmlChar *ch, int len) {
[(__bridge RSSAXParser *)context xmlCharactersFound:ch length:(NSUInteger)len];
}
static void endDocumentSAX(void *context) {
[(__bridge RSSAXParser *)context xmlEndDocument];
}
static xmlSAXHandler saxHandlerStruct = {
nil, /* internalSubset */
nil, /* isStandalone */
nil, /* hasInternalSubset */
nil, /* hasExternalSubset */
nil, /* resolveEntity */
nil, /* getEntity */
nil, /* entityDecl */
nil, /* notationDecl */
nil, /* attributeDecl */
nil, /* elementDecl */
nil, /* unparsedEntityDecl */
nil, /* setDocumentLocator */
nil, /* startDocument */
endDocumentSAX, /* endDocument */
nil, /* startElement*/
nil, /* endElement */
nil, /* reference */
charactersFoundSAX, /* characters */
nil, /* ignorableWhitespace */
nil, /* processingInstruction */
nil, /* comment */
nil, /* warning */
nil, /* error */
nil, /* fatalError //: unused error() get all the errors */
nil, /* getParameterEntity */
nil, /* cdataBlock */
nil, /* externalSubset */
XML_SAX2_MAGIC,
nil,
startElementSAX, /* startElementNs */
endElementSAX, /* endElementNs */
nil /* serror */
};
void RSSAXInitLibXMLParser(void) {
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
xmlInitParser();
});
}