radare2/libr/util/uleb128.c
2012-07-12 02:47:04 +02:00

39 lines
702 B
C

#include <r_util.h>
/* dwarf uleb128 implementation */
R_API const ut8 *r_uleb128 (const ut8 *data, ut32 *v) {
ut8 c;
ut32 s, sum;
for (s = sum = 0; ; s+= 7) {
c = *(data++) & 0xff;
sum |= ((ut32) (c&0x7f)<<s);
if (!(c&0x80)) break;
}
if (v) *v = sum;
return data;
}
R_API const ut8 *r_leb128 (const ut8 *data, st32 *v) {
ut8 c;
st32 s, sum;
for (s = sum = 0; ; s+= 7) {
c = *data++ & 0x0ff;
sum |= ((st32) ((*data++) & 0x7f) << s);
if (!(c&0x80)) break;
}
if ((s < (8 * sizeof (sum))) && (c & 0x40))
sum |= -(((long)1) << s);
if (v) *v = sum;
return data;
}
#if 0
main() {
ut32 n;
ut8 *buf = "\x10\x02\x90\x88";
r_uleb128 (buf, &n);
printf ("n = %d\n", n);
}
#endif