十六进制字符串转十六进制字节代码

/*********************************************************************************
 *      Copyright:  (C) 2016 Guo Wenxue<[email protected]>
 *                  All rights reserved.
 *
 *       Filename:  strhex.c
 *    Description:  This file used convert HEX string to HEX bytes and write into file
 *
 *        Version:  1.0.0(09/20/2016)
 *         Author:  Guo Wenxue <[email protected]>
 *      ChangeLog:  1, Release initial version on "09/20/2016 09:16:41 AM"
 *
 ********************************************************************************/
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>

//#define DEBUG
#ifdef  DEBUG
#define dbg_print(format,args...) printf(format, ##args)
#else
#define dbg_print(format,args...) do{} while(0);
#endif

int hexStr2Bytes(char *hexstr, int strlen, unsigned  char *bytes)
{
    int           i;
    int           cnt = 0; 

    for(i=0; i<strlen; i++)
    {
        dbg_print("%c", hexstr[i]);
    }
    dbg_print("\n");

    for (i=0; i<strlen; i++)
    {
        if( !isxdigit(hexstr[i]) )
        {
            continue;
        }

        dbg_print("proc ‘%c‘ ", hexstr[i]);
        if ((hexstr[i] >= ‘0‘) && (hexstr[i] <= ‘9‘))
            *bytes = (hexstr[i]-‘0‘) << 4;
        else
            *bytes = (toupper(hexstr[i])-‘A‘+10) <<4;
        dbg_print("[0x%02x] ", *bytes);

        i++;

        dbg_print("proc ‘%c‘ ", hexstr[i]);
        if ((hexstr[i] >= ‘0‘) && (hexstr[i] <= ‘9‘))
            *bytes |= hexstr[i]-‘0‘;
        else
            *bytes |= toupper(hexstr[i])-‘A‘+10;
        dbg_print("=>[0x%02x]\n", *bytes);

        bytes++;
        cnt ++;
    }

    return cnt;
}

int main (int argc, char **argv)
{
    char                *filename;
    unsigned char       buf[1024];
    char                *hexstr;
    int                 bytes;
    int                 fd;
    int                 i; 

    if(argc != 3 )
    {
        printf("Usage: %s [filename] [hexstr]\n", argv[0]);
        return -1;
    }

    filename = argv[1];
    hexstr = argv[2];

    if( (fd=open(filename, O_CREAT|O_TRUNC|O_RDWR, 0666)) < 0 )
    {
        printf("Open file ‘%s‘ failure: %s\n", filename, strerror(errno));
        return -2;
    }

    bytes = hexStr2Bytes(hexstr, strlen(hexstr), buf);

    write(fd, buf, bytes);

    close(fd);

    return 0;
} 

[[email protected] ~]$ ./strhex f1.txt "1B 40 76 4C 4C 93 09 CA 72 8A C2 02 02 02 8A C2
> D2 A2 92 D2 A2 9A 02 02 02 82 8A 82 92 82 8A 8A
> 52 1C 26 1C 2E 1B 69 01 1C 26 C7 EB C7 F3 1C 2E
> 1B 69 00 1B 69 01 30 30 34 1B 69 00 1B 6C 0C 1C
> 26 B0 CB B2 E3 20 20 B9 E3 B2 A5 1C 2E 0D 1B 6C
> 00 0D 0A"