de = de85[ch];
if (--de < 0)
return error("invalid base85 alphabet %c", ch);
- /*
- * Detect overflow. The largest
- * 5-letter possible is "|NsC0" to
- * encode 0xffffffff, and "|NsC" gives
- * 0x03030303 at this point (i.e.
- * 0xffffffff = 0x03030303 * 85).
- */
- if (0x03030303 < acc ||
+ /* Detect overflow. */
+ if (0xffffffff / 85 < acc ||
0xffffffff - de < (acc *= 85))
- error("invalid base85 sequence %.5s", buffer-5);
+ return error("invalid base85 sequence %.5s", buffer-5);
acc += de;
say1(" %08x", acc);
void encode_85(char *buf, const unsigned char *data, int bytes)
{
- prep_base85();
-
say("encode 85");
while (bytes) {
unsigned acc = 0;
int cnt;
for (cnt = 24; cnt >= 0; cnt -= 8) {
- int ch = *data++;
+ unsigned ch = *data++;
acc |= ch << cnt;
if (--bytes == 0)
break;
int len = strlen(av[2]);
encode_85(buf, av[2], len);
if (len <= 26) len = len + 'A' - 1;
- else len = len + 'a' - 26 + 1;
+ else len = len + 'a' - 26 - 1;
printf("encoded: %c%s\n", len, buf);
return 0;
}