/*

     File: QHex.m

 Abstract: Hex dump utilities.

  Version: 1.0

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 Software, with or without modifications, in source and/or binary forms;

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 Neither the name, trademarks, service marks or logos of Apple Inc. may

 be used to endorse or promote products derived from the Apple Software

 without specific prior written permission from Apple.  Except as

 expressly stated in this notice, no other rights or licenses, express or

 implied, are granted by Apple herein, including but not limited to any

 patent rights that may be infringed by your derivative works or by other

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 The Apple Software is provided by Apple on an "AS IS" basis.  APPLE

 MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION

 THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS

 FOR A PARTICULAR PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND

 OPERATION ALONE OR IN COMBINATION WITH YOUR PRODUCTS.

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 */

#import "QHex.h"

@implementation QHex

+ (NSString *)hexStringWithBytes:(const void *)bytes length:(NSUInteger)length

{

    NSMutableString *   result;

    result = [[NSMutableString alloc] initWithCapacity:length * 2];

    for (size_t i = 0; i < length; i++) {

        [result appendFormat:@"%02x", ((const uint8_t *) bytes)[i]];

    }

    return result;

}

+ (NSString *)hexStringWithData:(NSData *)data

{

    return [[self class] hexStringWithBytes:[data bytes] length:[data length]];

}

+ (NSData *)dataWithHexString:(NSString *)hexString

{

    NSMutableData *     result;

    NSUInteger          cursor;

    NSUInteger          limit;

    result = nil;

    cursor = 0;

    limit = [hexString length];

    if ((limit % 2) == 0) {

        result = [[NSMutableData alloc] init];

        while (cursor != limit) {

            unsigned int    thisUInt;

            uint8_t         thisByte;

            if ( sscanf([[hexString substringWithRange:NSMakeRange(cursor, 2)] UTF8String], "%x", &thisUInt) != 1 ) {

                result = nil;

                break;

            }

            thisByte = (uint8_t) thisUInt;

            [result appendBytes:&thisByte length:sizeof(thisByte)];

            cursor += 2;

        }

    }

    return result;

}

@end