更新时间:2023-11-15 19:49:40
您可以使用与strtol()
代替。
只需更换这行:
的sscanf(POS,%2hhx,&安培; VAL [计数]);
与
字符BUF [10];
sprintf的(BUF,0X%C%C,POS [0],POS [1]);
VAL [计数] =与strtol(BUF,NULL,0);
更新:你能避免使用的sprintf()
使用这段代码来代替:
字符BUF [5] = {0,X,POS [0],POS [1],0};
VAL [计数] =与strtol(BUF,NULL,0);
I need to convert a string, containing hex values as characters, into a byte array. Although this has been answered already here as the first answer, I get the following error:
warning: ISO C90 does not support the ‘hh’ gnu_scanf length modifier [-Wformat]
Since I do not like warnings, and the omission of hh
just creates another warning
warning: format ‘%x’ expects argument of type ‘unsigned int *’, but argument 3 has type ‘unsigned char *’ [-Wformat]
my question is: How to do this right? For completion, I post the example code here again:
#include <stdio.h>
int main(int argc, char **argv)
{
const char hexstring[] = "deadbeef10203040b00b1e50", *pos = hexstring;
unsigned char val[12];
size_t count = 0;
/* WARNING: no sanitization or error-checking whatsoever */
for(count = 0; count < sizeof(val)/sizeof(val[0]); count++) {
sscanf(pos, "%2hhx", &val[count]);
pos += 2 * sizeof(char);
}
printf("0x");
for(count = 0; count < sizeof(val)/sizeof(val[0]); count++)
printf("%02x", val[count]);
printf("\n");
return(0);
}
You can use strtol()
instead.
Simply replace this line:
sscanf(pos, "%2hhx", &val[count]);
with:
char buf[10];
sprintf(buf, "0x%c%c", pos[0], pos[1]);
val[count] = strtol(buf, NULL, 0);
UPDATE: You can avoid using sprintf()
using this snippet instead:
char buf[5] = {"0", "x", pos[0], pos[1], 0};
val[count] = strtol(buf, NULL, 0);