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@munho
Forked from xsleonard/gist:7341172
Created December 18, 2024 05:45
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hex string to byte array, C
unsigned char* hexstr_to_char(const char* hexstr)
{
size_t len = strlen(hexstr);
IF_ASSERT(len % 2 != 0)
return NULL;
size_t final_len = len / 2;
unsigned char* chrs = (unsigned char*)malloc((final_len+1) * sizeof(*chrs));
for (size_t i=0, j=0; j<final_len; i+=2, j++)
chrs[j] = (hexstr[i] % 32 + 9) % 25 * 16 + (hexstr[i+1] % 32 + 9) % 25;
chrs[final_len] = '\0';
return chrs;
}
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