1*cdfa2a7eSchristos /* $NetBSD: atouint.c,v 1.9 2020/05/25 20:47:24 christos Exp $ */ 2abb0f93cSkardel 32950cc38Schristos #include <config.h> 4abb0f93cSkardel #include <sys/types.h> 5abb0f93cSkardel #include <ctype.h> 6abb0f93cSkardel 7abb0f93cSkardel #include "ntp_types.h" 8abb0f93cSkardel #include "ntp_stdlib.h" 9abb0f93cSkardel 102950cc38Schristos /* 112950cc38Schristos * atouint() - convert an ascii string representing a whole base 10 122950cc38Schristos * number to u_long *uval, returning TRUE if successful. 132950cc38Schristos * Does not modify *uval and returns FALSE if str is not 142950cc38Schristos * a positive base10 integer or is too large for a u_int32. 152950cc38Schristos * this function uses u_long but should use u_int32, and 162950cc38Schristos * probably be renamed. 172950cc38Schristos */ 18abb0f93cSkardel int atouint(const char * str,u_long * uval)19abb0f93cSkardelatouint( 20abb0f93cSkardel const char *str, 21abb0f93cSkardel u_long *uval 22abb0f93cSkardel ) 23abb0f93cSkardel { 242950cc38Schristos u_long u; 252950cc38Schristos const char *cp; 26abb0f93cSkardel 27abb0f93cSkardel cp = str; 282950cc38Schristos if ('\0' == *cp) 29abb0f93cSkardel return 0; 30abb0f93cSkardel 31abb0f93cSkardel u = 0; 322950cc38Schristos while ('\0' != *cp) { 33ed38567fSchristos if (!isdigit((unsigned char)*cp)) 34abb0f93cSkardel return 0; 35abb0f93cSkardel if (u > 429496729 || (u == 429496729 && *cp >= '6')) 36abb0f93cSkardel return 0; /* overflow */ 372950cc38Schristos /* hand-optimized u *= 10; */ 38abb0f93cSkardel u = (u << 3) + (u << 1); 392950cc38Schristos u += *cp++ - '0'; /* not '\0' */ 40abb0f93cSkardel } 41abb0f93cSkardel 42abb0f93cSkardel *uval = u; 43abb0f93cSkardel return 1; 44abb0f93cSkardel } 45