NetNewsWire/Frameworks/RSParser/HTML/RSSAXHTMLParser.m

316 lines
6.7 KiB
Objective-C
Executable File

//
// RSSAXHTMLParser.m
// RSParser
//
// Created by Brent Simmons on 3/6/16.
// Copyright © 2016 Ranchero Software, LLC. All rights reserved.
//
#import "RSSAXHTMLParser.h"
#import "RSSAXParser.h"
#import <libxml/tree.h>
#import <libxml/xmlstring.h>
#import <libxml/HTMLparser.h>
#import "RSParserInternal.h"
@interface RSSAXHTMLParser ()
@property (nonatomic) id<RSSAXHTMLParserDelegate> delegate;
@property (nonatomic, assign) htmlParserCtxtPtr context;
@property (nonatomic, assign) BOOL storingCharacters;
@property (nonatomic) NSMutableData *characters;
@property (nonatomic) BOOL delegateRespondsToStartElementMethod;
@property (nonatomic) BOOL delegateRespondsToEndElementMethod;
@property (nonatomic) BOOL delegateRespondsToCharactersFoundMethod;
@property (nonatomic) BOOL delegateRespondsToEndOfDocumentMethod;
@end
@implementation RSSAXHTMLParser
+ (void)initialize {
RSSAXInitLibXMLParser();
}
#pragma mark - Init
- (instancetype)initWithDelegate:(id<RSSAXHTMLParserDelegate>)delegate {
self = [super init];
if (self == nil)
return nil;
_delegate = delegate;
if ([_delegate respondsToSelector:@selector(saxParser:XMLStartElement:attributes:)]) {
_delegateRespondsToStartElementMethod = YES;
}
if ([_delegate respondsToSelector:@selector(saxParser:XMLEndElement:)]) {
_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) {
htmlFreeParserCtxt(_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) {
xmlCharEncoding characterEncoding = xmlDetectCharEncoding(bytes, (int)numberOfBytes);
self.context = htmlCreatePushParserCtxt(&saxHandlerStruct, (__bridge void *)self, nil, 0, nil, characterEncoding);
htmlCtxtUseOptions(self.context, XML_PARSE_RECOVER | XML_PARSE_NONET | HTML_PARSE_COMPACT);
}
@autoreleasepool {
htmlParseChunk(self.context, (const char *)bytes, (int)numberOfBytes, 0);
}
}
- (void)finishParsing {
NSAssert(self.context != nil, nil);
if (self.context == nil)
return;
@autoreleasepool {
htmlParseChunk(self.context, nil, 0, 1);
htmlFreeParserCtxt(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 {
if (!attributes) {
return nil;
}
NSMutableDictionary *d = [NSMutableDictionary new];
NSInteger ix = 0;
NSString *currentKey = nil;
while (true) {
const xmlChar *oneAttribute = attributes[ix];
ix++;
if (!currentKey && !oneAttribute) {
break;
}
if (!currentKey) {
currentKey = [NSString stringWithUTF8String:(const char *)oneAttribute];
}
else {
NSString *value = nil;
if (oneAttribute) {
value = [NSString stringWithUTF8String:(const char *)oneAttribute];
}
d[currentKey] = value ? value : @"";
currentKey = nil;
}
}
return [d copy];
}
#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 attributes:(const xmlChar **)attributes {
@autoreleasepool {
if (self.delegateRespondsToStartElementMethod) {
[self.delegate saxParser:self XMLStartElement:localName attributes:attributes];
}
}
}
- (void)xmlEndElement:(const xmlChar *)localName {
@autoreleasepool {
if (self.delegateRespondsToEndElementMethod) {
[self.delegate saxParser:self XMLEndElement:localName];
}
[self endStoringCharacters];
}
}
@end
static void startElementSAX(void *context, const xmlChar *localname, const xmlChar **attributes) {
[(__bridge RSSAXHTMLParser *)context xmlStartElement:localname attributes:attributes];
}
static void endElementSAX(void *context, const xmlChar *localname) {
[(__bridge RSSAXHTMLParser *)context xmlEndElement:localname];
}
static void charactersFoundSAX(void *context, const xmlChar *ch, int len) {
[(__bridge RSSAXHTMLParser *)context xmlCharactersFound:ch length:(NSUInteger)len];
}
static void endDocumentSAX(void *context) {
[(__bridge RSSAXHTMLParser *)context xmlEndDocument];
}
static htmlSAXHandler 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 */
startElementSAX, /* startElement*/
endElementSAX, /* 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,
nil, /* startElementNs */
nil, /* endElementNs */
nil /* serror */
};