hexToAscii

最新推荐文章于 2025-06-16 14:30:32 发布

转载最新推荐文章于 2025-06-16 14:30:32 发布 · 243 阅读

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原文链接：http://www.cnblogs.com/noselhq/archive/2012/11/08/2760611.html

char *hexToAscii (char *srcHex, int *destElements, int srcElements)
{
    int        index, destIndex;
    unsigned char    valUpper, valLower, *ascArray;
    int        lowerFlag;

    lowerFlag = 0;
    ascArray = NULL;
    *destElements = srcElements/2;
    ascArray = (char *)malloc (*destElements);
    if (ascArray == NULL) {
        return NULL;
    }
    for (destIndex = 0; destIndex < *destElements; destIndex++) {
        //  Every hex value will be 2 nibbles long and will take up 2 character
        //  space in the character array (Input)
        for (index = 0; index < 2; index++) {
            if (lowerFlag == 0) {
                if (srcHex[(destIndex * 2) + index] >= '0' &&
                    srcHex[(destIndex * 2) + index] <= '9') {
                    valUpper = srcHex[(destIndex * 2) + index] - '0';
                } else if (tolower (srcHex[(destIndex * 2) + index]) >= 'a' ||
                           tolower (srcHex[(destIndex * 2) + index]) <= 'f'){
                    valUpper = tolower(srcHex[(destIndex * 2) + index]) - 'a' + 10;
                }
                //  The first character represent the upper nibble (upper 4 bits)
                //  of the hex value. Shift the converted value left 4 bits
                valUpper <<= 4;
                lowerFlag = 1;
            } else {
                if (srcHex[(destIndex * 2) + index] >= '0' &&
                    srcHex[(destIndex * 2) + index] <= '9') {
                    valLower = srcHex[(destIndex * 2) + index] - '0';
                } else if (tolower (srcHex[(destIndex * 2) + index]) >= 'a' ||
                           tolower (srcHex[(destIndex * 2) + index]) <= 'f'){
                    valLower = tolower (srcHex[(destIndex * 2) + index]) - 'a' + 10;
                }
                lowerFlag = 0;
           }
    }
       //  ANDing upper and lower values will get the proper 8 bit ASCII converted val
       ascArray[destIndex] = valUpper | valLower;
    }
    return ascArray;
}

转载于:https://www.cnblogs.com/noselhq/archive/2012/11/08/2760611.html