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memory mapped core graphics data consumer for writing PDFs
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#import <Foundation/Foundation.h> | |
#import <CoreGraphics/CoreGraphics.h> | |
@interface MemoryMappedDataConsumer : NSObject | |
@property ( nonatomic, readonly ) size_t size ; | |
@property ( nonatomic, readonly ) size_t capacity ; | |
@property ( nonatomic, readonly ) CGDataConsumerRef CGDataConsumer ; | |
@property ( nonatomic, readonly, copy ) NSURL * url ; | |
-(id)initWithURL:(NSURL*)url ; | |
@end |
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#import "MemoryMappedDataConsumer.h" | |
#import <sys/mman.h> | |
@interface MemoryMappedDataConsumer () | |
// private | |
@property ( nonatomic ) size_t size ; | |
@property ( nonatomic ) size_t capacity ; | |
@property ( nonatomic, strong, readonly ) NSFileHandle * fileHandle ; | |
@property ( nonatomic ) void * buffer ; | |
@property ( nonatomic, copy ) NSURL * url ; | |
-(size_t)putBytes:(const void *)bytes count:(size_t)count ; | |
@end | |
@implementation MemoryMappedDataConsumer | |
@synthesize CGDataConsumer = _CGDataConsumer ; | |
@synthesize fileHandle = _fileHandle ; | |
static size_t DataConsumerPutBytesCallback( MemoryMappedDataConsumer * consumer, const void *buffer, size_t count) | |
{ | |
return [ consumer putBytes:buffer count:count ] ; | |
} | |
static void DataConsumerReleaseConsumer( MemoryMappedDataConsumer * consumer ) | |
{ | |
CFRelease((__bridge CFTypeRef)consumer); | |
} | |
-(id)initWithURL:(NSURL*)url | |
{ | |
if (( self = [ super init ] )) | |
{ | |
self.url = url ; | |
} | |
return self ; | |
} | |
-(CGDataConsumerRef)CGDataConsumer | |
{ | |
if ( !_CGDataConsumer ) | |
{ | |
_CGDataConsumer = CGDataConsumerCreate( (__bridge_retained void *)self, &(CGDataConsumerCallbacks){ | |
.putBytes = (CGDataConsumerPutBytesCallback)DataConsumerPutBytesCallback, | |
.releaseConsumer = (CGDataConsumerReleaseInfoCallback)DataConsumerReleaseConsumer | |
}); | |
} | |
return _CGDataConsumer ; | |
} | |
-(size_t)putBytes:(const void *)bytes count:(size_t)count | |
{ | |
size_t newSize = self.size + count ; | |
if ( newSize > self.capacity ) | |
{ | |
size_t newCapacity = self.capacity ; | |
newCapacity += newCapacity >> 1 ; | |
newCapacity = round_page( MAX( newCapacity, MAX( 4 * getpagesize(), count ) ) ) ; | |
[ self.fileHandle truncateFileAtOffset:newCapacity ] ; | |
if ( self.buffer && self.capacity ) | |
{ | |
munmap( self.buffer, self.capacity ) ; | |
} | |
void * newBuffer = mmap( self.buffer | |
, newCapacity | |
, PROT_WRITE | PROT_READ | |
, MAP_SHARED | |
, self.fileHandle.fileDescriptor | |
, 0 ) ; | |
if ( !newBuffer || newBuffer == (void*)~0l ) // mmap returns (-1) on error | |
{ | |
// couldn't expand buffer, bail: | |
return 0 ; | |
} | |
self.buffer = newBuffer ; | |
self.capacity = newCapacity ; | |
} | |
bcopy( bytes, self.buffer + self.size, count ) ; | |
self.size = newSize ; | |
return count ; | |
} | |
-(NSFileHandle *)fileHandle | |
{ | |
if ( !_fileHandle ) | |
{ | |
NSError * error = nil ; | |
NSFileManager * fileManager = [ NSFileManager defaultManager ] ; | |
if ( ![ fileManager fileExistsAtPath:self.url.path ] ) | |
{ | |
BOOL success = [ fileManager createFileAtPath:self.url.path contents:nil attributes:nil ] ; | |
if ( !success ) | |
{ | |
@throw @"Couldn't create backing store file" ; | |
} | |
} | |
NSFileHandle * fileHandle = [ NSFileHandle fileHandleForUpdatingURL:self.url error:&error ] ; | |
if ( !fileHandle ) | |
{ | |
if ( error ) { @throw error ; } | |
} | |
_fileHandle = fileHandle ; | |
} | |
return _fileHandle ; | |
} | |
@end | |
// mediaBox and auxInfoDict can be NULL | |
CGContextRef CreateMemoryMappedPDFContext( NSURL * fileURL, const CGRect * mediaBox, CFDictionaryRef auxInfoDict ) | |
{ | |
MemoryMappedDataConsumer * consumer = [ [ MemoryMappedDataConsumer alloc ] initWithURL:fileURL ] ; | |
CGContextRef c = CGPDFContextCreate( [ consumer CGDataConsumer ], mediaBox, auxInfoDict ) ; | |
return c ; | |
} |
I can check
I added it to a project and it works fine...
I added an import for sys/mman.h
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Hi, I understand that it's old gist... Is it possible compile in XCode 7?