You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
38 lines
769 B
C
38 lines
769 B
C
#include "scan.h"
|
|
|
|
int scan_fromhex(unsigned char c) {
|
|
c=(unsigned char)(c-'0');
|
|
if (c<=9) return c;
|
|
c=(unsigned char)(c&~0x20);
|
|
c=(unsigned char)(c-('A'-'0'));
|
|
if (c<6) return c+10;
|
|
return -1;
|
|
/* more readable but creates worse code:
|
|
if (c>='0' && c<='9')
|
|
return c-'0';
|
|
else if (c>='A' && c<='F')
|
|
return c-'A'+10;
|
|
else if (c>='a' && c<='f')
|
|
return c-'a'+10;
|
|
return -1;
|
|
*/
|
|
}
|
|
|
|
#ifdef UNITTEST
|
|
#include <assert.h>
|
|
int main() {
|
|
int i;
|
|
for (i=0; i<256; ++i) {
|
|
if (i>='0' && i<='9')
|
|
assert(scan_fromhex(i)==i-'0');
|
|
else if (i>='a' && i<='f')
|
|
assert(scan_fromhex(i)==i-'a'+10);
|
|
else if (i>='A' && i<='F')
|
|
assert(scan_fromhex(i)==i-'A'+10);
|
|
else
|
|
assert(scan_fromhex(i)==-1);
|
|
}
|
|
return 0;
|
|
}
|
|
#endif
|