AFNetworking/AFNetworking/NSData+AFNetworking.m

128 lines
4.6 KiB
Objective-C

// NSData+AFNetworking.m
//
// Copyright (c) 2011 Gowalla (http://gowalla.com/)
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
#import "NSData+AFNetworking.h"
#import <zlib.h>
NSString * const kAFZlibErrorDomain = @"com.alamofire.zlib.error";
static char Base64EncodingTable[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
static inline NSUInteger NSDataEstimatedCompressedLength(NSData *data) {
return [data length] / 2;
}
typedef enum {
GzipDeflate = -1,
GzipInflate = 1,
} GzipOperation;
@interface NSData (_AFNetworking)
+ (NSData *)dataByTransformingData:(NSData *)data
usingGZipOperation:(GzipOperation)operation
error:(NSError **)error;
@end
@implementation NSData (_AFNetworking)
+ (NSData *)dataByTransformingData:(NSData *)data
usingGZipOperation:(GzipOperation)operation
error:(NSError **)error
{
z_stream zStream;
NSUInteger estimatedLength = NSDataEstimatedCompressedLength(data);
NSMutableData *mutableData = [NSMutableData dataWithLength:estimatedLength];
int status;
zStream.next_in = (Bytef *)[data bytes];
zStream.avail_in = (unsigned int)[data length];
zStream.avail_out = 0;
NSInteger bytesProcessedAlready = zStream.total_out;
while (zStream.avail_out == 0) {
if (zStream.total_out - bytesProcessedAlready >= [mutableData length]) {
[mutableData increaseLengthBy:estimatedLength / 2];
}
zStream.next_out = [mutableData mutableBytes] + zStream.total_out-bytesProcessedAlready;
zStream.avail_out = (unsigned int)([mutableData length] - (zStream.total_out-bytesProcessedAlready));
status = deflate(&zStream, Z_FINISH);
if (status == Z_STREAM_END) {
break;
} else if (status != Z_OK) {
if (error) {
*error = [NSError errorWithDomain:kAFZlibErrorDomain code:status userInfo:[NSDictionary dictionaryWithObject:[NSString stringWithFormat:@"Compression of data failed with code %hi", status] forKey:NSLocalizedDescriptionKey]];
}
return nil;
}
}
[mutableData setLength:zStream.total_out - bytesProcessedAlready];
return mutableData;
}
@end
#pragma mark -
@implementation NSData (AFNetworking)
- (NSString *)base64EncodedString {
NSUInteger length = [self length];
NSMutableData *mutableData = [NSMutableData dataWithLength:((length + 2) / 3) * 4];
uint8_t *input = (uint8_t *)[self bytes];
uint8_t *output = (uint8_t *)[mutableData mutableBytes];
for (NSUInteger i = 0; i < length; i += 3) {
NSUInteger value = 0;
for (NSUInteger j = i; j < (i + 3); j++) {
value <<= 8;
if (j < length) {
value |= (0xFF & input[j]);
}
}
NSInteger idx = (i / 3) * 4;
output[idx + 0] = Base64EncodingTable[(value >> 18) & 0x3F];
output[idx + 1] = Base64EncodingTable[(value >> 12) & 0x3F];
output[idx + 2] = (i + 1) < length ? Base64EncodingTable[(value >> 6) & 0x3F] : '=';
output[idx + 3] = (i + 2) < length ? Base64EncodingTable[(value >> 0) & 0x3F] : '=';
}
return [[[NSString alloc] initWithData:mutableData encoding:NSASCIIStringEncoding] autorelease];
}
- (NSData *)dataByGZipCompressingWithError:(NSError **)error {
return [NSData dataByTransformingData:self usingGZipOperation:GzipDeflate error:error];
}
- (NSData *)dataByGZipDecompressingDataWithError:(NSError **)error {
return [NSData dataByTransformingData:self usingGZipOperation:GzipInflate error:error];
}
@end