XADMaster/XADCompressParser.m

71 lines
2.3 KiB
Objective-C

/*
* XADCompressParser.m
*
* Copyright (c) 2017-present, MacPaw Inc. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA
*/
#import "XADCompressParser.h"
#import "XADCompressHandle.h"
@implementation XADCompressParser
+(int)requiredHeaderSize { return 3; }
+(BOOL)recognizeFileWithHandle:(CSHandle *)handle firstBytes:(NSData *)data name:(NSString *)name
{
int length=[data length];
const uint8_t *bytes=[data bytes];
return length>=3&&bytes[0]==0x1f&&bytes[1]==0x9d;
}
-(void)parse
{
CSHandle *fh=[self handle];
[fh skipBytes:2];
int flags=[fh readUInt8];
NSString *contentname=[[self name] stringByDeletingPathExtension];
NSMutableDictionary *dict=[NSMutableDictionary dictionaryWithObjectsAndKeys:
[self XADPathWithUnseparatedString:contentname],XADFileNameKey,
[self XADStringWithString:@"Compress"],XADCompressionNameKey,
[NSNumber numberWithLongLong:3],XADDataOffsetKey,
[NSNumber numberWithInt:flags],@"CompressFlags",
nil];
if([contentname matchedByPattern:@"\\.(tar|cpio|pax|warc)$" options:REG_ICASE])
[dict setObject:[NSNumber numberWithBool:YES] forKey:XADIsArchiveKey];
off_t size=[[self handle] fileSize];
if(size!=CSHandleMaxLength)
[dict setObject:[NSNumber numberWithLongLong:size-3] forKey:XADCompressedSizeKey];
[self addEntryWithDictionary:dict];
}
-(CSHandle *)handleForEntryWithDictionary:(NSDictionary *)dict wantChecksum:(BOOL)checksum
{
return [[[XADCompressHandle alloc] initWithHandle:[self handleAtDataOffsetForDictionary:dict]
flags:[[dict objectForKey:@"CompressFlags"] intValue]] autorelease];
}
-(NSString *)formatName { return @"Compress"; }
@end