/contrib/ntp/libntp/hextolfp.c
https://bitbucket.org/freebsd/freebsd-head/ · C · 67 lines · 49 code · 10 blank · 8 comment · 20 complexity · eb38b4b8c073ef82c1b4d7faa592da03 MD5 · raw file
- /*
- * hextolfp - convert an ascii hex string to an l_fp number
- */
- #include <stdio.h>
- #include <ctype.h>
- #include "ntp_fp.h"
- #include "ntp_string.h"
- #include "ntp_stdlib.h"
- int
- hextolfp(
- const char *str,
- l_fp *lfp
- )
- {
- register const char *cp;
- register const char *cpstart;
- register u_long dec_i;
- register u_long dec_f;
- char *ind = NULL;
- static const char *digits = "0123456789abcdefABCDEF";
- dec_i = dec_f = 0;
- cp = str;
- /*
- * We understand numbers of the form:
- *
- * [spaces]8_hex_digits[.]8_hex_digits[spaces|\n|\0]
- */
- while (isspace((int)*cp))
- cp++;
-
- cpstart = cp;
- while (*cp != '\0' && (cp - cpstart) < 8 &&
- (ind = strchr(digits, *cp)) != NULL) {
- dec_i = dec_i << 4; /* multiply by 16 */
- dec_i += ((ind - digits) > 15) ? (ind - digits) - 6
- : (ind - digits);
- cp++;
- }
- if ((cp - cpstart) < 8 || ind == NULL)
- return 0;
- if (*cp == '.')
- cp++;
- cpstart = cp;
- while (*cp != '\0' && (cp - cpstart) < 8 &&
- (ind = strchr(digits, *cp)) != NULL) {
- dec_f = dec_f << 4; /* multiply by 16 */
- dec_f += ((ind - digits) > 15) ? (ind - digits) - 6
- : (ind - digits);
- cp++;
- }
- if ((cp - cpstart) < 8 || ind == NULL)
- return 0;
-
- if (*cp != '\0' && !isspace((int)*cp))
- return 0;
- lfp->l_ui = dec_i;
- lfp->l_uf = dec_f;
- return 1;
- }