1 /* @(#)inet_network.c 4.2 10/07/82 */ 2 3 #include <sys/types.h> 4 #include <ctype.h> 5 6 /* 7 * Internet network address interpretation routine. 8 * The library routines call this routine to interpret 9 * network numbers. 10 */ 11 u_long 12 inet_network(cp) 13 register char *cp; 14 { 15 register u_long val, base, n; 16 register char c; 17 u_long parts[4], *pp = parts; 18 register int i; 19 20 again: 21 val = 0; base = 10; 22 if (*cp == '0') 23 base = 8, cp++; 24 if (*cp == 'x' || *cp == 'X') 25 base = 16, cp++; 26 while (c = *cp) { 27 if (isdigit(c)) { 28 val = (val * base) + (c - '0'); 29 cp++; 30 continue; 31 } 32 if (base == 16 && isxdigit(c)) { 33 val = (val << 4) + (c + 10 - (islower(c) ? 'a' : 'A')); 34 cp++; 35 continue; 36 } 37 break; 38 } 39 if (*cp == '.') { 40 if (pp >= parts + 4) 41 return (-1); 42 *pp++ = val, cp++; 43 goto again; 44 } 45 if (*cp && !isspace(*cp)) 46 return (-1); 47 *pp++ = val; 48 n = pp - parts; 49 if (n > 4) 50 return (-1); 51 for (val = 0, i = 0; i < n; i++) { 52 val <<= 8; 53 val |= parts[i] & 0xff; 54 } 55 return (val); 56 } 57