1 /* @(#)inet_network.c 4.1 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 19 again: 20 val = 0; base = 10; 21 if (*cp == '0') 22 base = 8, cp++; 23 if (*cp == 'x' || *cp == 'X') 24 base = 16, cp++; 25 while (c = *cp) { 26 if (isdigit(c)) { 27 val = (val * base) + (c - '0'); 28 cp++; 29 continue; 30 } 31 if (base == 16 && isxdigit(c)) { 32 val = (val << 4) + (c + 10 - (islower(c) ? 'a' : 'A')); 33 cp++; 34 continue; 35 } 36 break; 37 } 38 if (*cp == '.') { 39 if (pp >= parts + 4) 40 return (-1); 41 *pp++ = val, cp++; 42 goto again; 43 } 44 if (*cp && !isspace(*cp)) 45 return (-1); 46 *pp++ = val; 47 n = pp - parts; 48 if (n > 4) 49 return (-1); 50 for (val = 0, i = 0; i < n; i++) { 51 val <<= 8; 52 val |= parts[i] & 0xff; 53 } 54 return (val); 55 } 56