arq_restore/plist/XMLPListReader.m

/*
 Copyright (c) 2009-2011, Stefan Reitshamer http://www.haystacksoftware.com
 
 All rights reserved.
 
 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 names of PhotoMinds LLC or Haystack Software, nor the names of 
 their 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 "ArrayNode.h"
#import "BooleanNode.h"
#import "DictNode.h"
#import "IntegerNode.h"
#import "RealNode.h"
#import "StringNode.h"
#import "PListNode.h"
#import "PListNodeType.h"
#import "XMLPListReader.h"
#import "SetNSError.h"

@interface XMLPListReader (internal)
- (ArrayNode *)readArray:(NSXMLNode *)elem error:(NSError **)error;
- (DictNode *)readDict:(NSXMLNode *)elem error:(NSError **)error;
- (id <PListNode>)makeNode:(NSXMLNode *)child error:(NSError **)error;
@end


@implementation XMLPListReader
- (id)initWithData:(NSData *)theData {
	if (self = [super init]) {
		data = [theData retain];
	}
	return self;
}
- (void)dealloc {
	[data release];
	[super dealloc];
}
- (DictNode *)read:(NSError **)error {
	NSXMLDocument *doc = [[NSXMLDocument alloc] initWithData:data options:0	error:error];
	if (!doc) {
        return nil;
	}
    DictNode *dn = nil;
    NSXMLElement *rootElem = [doc rootElement];
    if (![[rootElem name] isEqualToString:@"plist"]) {
        SETNSERROR(@"PListErrorDomain", -1, @"expected root element 'plist'");
        [doc release];
        return nil;
    }
    ArrayNode *an = [self readArray:rootElem error:error];
    if (!an) {
        [doc release];
        return nil;
    }
    if ([an size] != 1) {
        SETNSERROR(@"PListErrorDomain", -1, @"empty root array in PList");
        [doc release];
        return nil;
    }
    if ([an arrayElementsType] != PLN_DICT) {
        SETNSERROR(@"PListErrorDomain", -1, @"expected root array in PList");
        [doc release];
        return nil;
    }
    dn = (DictNode *)[an objectAtIndex:0];
    [doc release];
    return dn;
}
@end

@implementation XMLPListReader (internal)
- (ArrayNode *)readArray:(NSXMLNode *)elem error:(NSError **)error {
	NSMutableArray *nodes = [[NSMutableArray alloc] init];
	NSArray *children = [elem children];
	for (NSXMLNode *childNode in children) {
		if ([childNode kind] == NSXMLTextKind) {
			// Skip.
		} else {
            id <PListNode> node = [self makeNode:childNode error:error];
            if (!node) {
                [nodes release];
                return NO;
            }
			[nodes addObject:node];
		}
	}
	ArrayNode *ret = [[[ArrayNode alloc] initWithArray:nodes] autorelease];
	[nodes release];
	return ret;
}
- (DictNode *)readDict:(NSXMLNode *)elem error:(NSError **)error {
	DictNode *dn = [[[DictNode alloc] init] autorelease];
	NSArray *children = [elem children];
	NSString *key = nil;
	for (NSXMLNode *childNode in children) {
		if ([childNode kind] == NSXMLTextKind) {
			// Skip.
		} else {
			NSString *childNodeName = [childNode name];
			if ([childNodeName isEqualToString:@"key"]) {
				key = [childNode stringValue];
			} else {
                id <PListNode> node = [self makeNode:childNode error:error];
                if (!node) {
                    return NO;
                }
				NSAssert(key != nil, @"must have key before adding value");
				[dn put:node forKey:key];
			}
		}
	}
	return dn;
}
- (id <PListNode>)makeNode:(NSXMLNode *)child error:(NSError **)error {
	NSString *childName = [child name];
	id <PListNode> ret = nil;
	if ([childName isEqualToString:@"array"]) {
		ret = [self readArray:child error:error];
	} else if ([childName isEqualToString:@"dict"]) {
		ret = [self readDict:child error:error];
	} else if ([childName isEqualToString:@"true"]) {
		ret = [[[BooleanNode alloc] initWithBoolean:YES] autorelease];
	} else if ([childName isEqualToString:@"false"]) {
		ret = [[[BooleanNode alloc] initWithBoolean:NO] autorelease];
	} else if ([childName isEqualToString:@"integer"]) {
        IntegerNode *node = [[[IntegerNode alloc] initWithString:[child stringValue] error:error] autorelease];
        if (node) {
            ret = node;
        }
	} else if ([childName isEqualToString:@"real"]) {
		RealNode *node = [[[RealNode alloc] initWithString:[child stringValue] error:error] autorelease];
        if (node) {
            ret = node;
        }
	} else if ([childName isEqualToString:@"string"]) {
        NSString *value = (NSString *)CFXMLCreateStringByUnescapingEntities(kCFAllocatorDefault, (CFStringRef)[child stringValue], NULL);
		ret = [[[StringNode alloc] initWithString:value] autorelease];
        [value release];
	} else {
        SETNSERROR(@"PListErrorDomain", -1, @"invalid node type");
	}
	return ret;
}
@end