1 #include <config.h> 2 #include <sys/types.h> 3 #include <ctype.h> 4 5 #include "ntp_types.h" 6 #include "ntp_stdlib.h" 7 8 /* 9 * atouint() - convert an ascii string representing a whole base 10 10 * number to u_long *uval, returning TRUE if successful. 11 * Does not modify *uval and returns FALSE if str is not 12 * a positive base10 integer or is too large for a u_int32. 13 * this function uses u_long but should use u_int32, and 14 * probably be renamed. 15 */ 16 int 17 atouint( 18 const char *str, 19 u_long *uval 20 ) 21 { 22 u_long u; 23 const char *cp; 24 25 cp = str; 26 if ('\0' == *cp) 27 return 0; 28 29 u = 0; 30 while ('\0' != *cp) { 31 if (!isdigit((unsigned char)*cp)) 32 return 0; 33 if (u > 429496729 || (u == 429496729 && *cp >= '6')) 34 return 0; /* overflow */ 35 /* hand-optimized u *= 10; */ 36 u = (u << 3) + (u << 1); 37 u += *cp++ - '0'; /* not '\0' */ 38 } 39 40 *uval = u; 41 return 1; 42 } 43