* from Red Hat. I didn't look at their source code, but there
* is no denying that this is a loving reimplementation
*
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
-#include <sys/socket.h>
-#include <arpa/inet.h>
+//usage:#define ipcalc_trivial_usage
+//usage: "[OPTIONS] ADDRESS[[/]NETMASK] [NETMASK]"
+//usage:#define ipcalc_full_usage "\n\n"
+//usage: "Calculate IP network settings from a IP address\n"
+//usage: IF_FEATURE_IPCALC_LONG_OPTIONS(
+//usage: "\n -b,--broadcast Display calculated broadcast address"
+//usage: "\n -n,--network Display calculated network address"
+//usage: "\n -m,--netmask Display default netmask for IP"
+//usage: IF_FEATURE_IPCALC_FANCY(
+//usage: "\n -p,--prefix Display the prefix for IP/NETMASK"
+//usage: "\n -h,--hostname Display first resolved host name"
+//usage: "\n -s,--silent Don't ever display error messages"
+//usage: )
+//usage: )
+//usage: IF_NOT_FEATURE_IPCALC_LONG_OPTIONS(
+//usage: "\n -b Display calculated broadcast address"
+//usage: "\n -n Display calculated network address"
+//usage: "\n -m Display default netmask for IP"
+//usage: IF_FEATURE_IPCALC_FANCY(
+//usage: "\n -p Display the prefix for IP/NETMASK"
+//usage: "\n -h Display first resolved host name"
+//usage: "\n -s Don't ever display error messages"
+//usage: )
+//usage: )
#include "libbb.h"
+/* After libbb.h, because on some systems it needs other includes */
+#include <arpa/inet.h>
-#define CLASS_A_NETMASK ntohl(0xFF000000)
-#define CLASS_B_NETMASK ntohl(0xFFFF0000)
-#define CLASS_C_NETMASK ntohl(0xFFFFFF00)
+#define CLASS_A_NETMASK ntohl(0xFF000000)
+#define CLASS_B_NETMASK ntohl(0xFFFF0000)
+#define CLASS_C_NETMASK ntohl(0xFFFFFF00)
static unsigned long get_netmask(unsigned long ipaddr)
{
#if ENABLE_FEATURE_IPCALC_LONG_OPTIONS
static const char ipcalc_longopts[] ALIGN1 =
- "netmask\0" No_argument "m"
- "broadcast\0" No_argument "b"
- "network\0" No_argument "n"
+ "netmask\0" No_argument "m" // netmask from IP (assuming complete class A, B, or C network)
+ "broadcast\0" No_argument "b" // broadcast from IP [netmask]
+ "network\0" No_argument "n" // network from IP [netmask]
# if ENABLE_FEATURE_IPCALC_FANCY
- "prefix\0" No_argument "p"
- "hostname\0" No_argument "h"
- "silent\0" No_argument "s"
+ "prefix\0" No_argument "p" // prefix from IP[/prefix] [netmask]
+ "hostname\0" No_argument "h" // hostname from IP
+ "silent\0" No_argument "s" // don’t ever display error messages
# endif
;
#endif
int ipcalc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int ipcalc_main(int argc, char **argv)
+int ipcalc_main(int argc UNUSED_PARAM, char **argv)
{
unsigned opt;
- int have_netmask = 0;
- in_addr_t netmask, broadcast, network, ipaddr;
- struct in_addr a;
+ bool have_netmask = 0;
+ struct in_addr s_netmask, s_broadcast, s_network, s_ipaddr;
+ /* struct in_addr { in_addr_t s_addr; } and in_addr_t
+ * (which in turn is just a typedef to uint32_t)
+ * are essentially the same type. A few macros for less verbosity: */
+#define netmask (s_netmask.s_addr)
+#define broadcast (s_broadcast.s_addr)
+#define network (s_network.s_addr)
+#define ipaddr (s_ipaddr.s_addr)
char *ipstr;
#if ENABLE_FEATURE_IPCALC_LONG_OPTIONS
applet_long_options = ipcalc_longopts;
#endif
- opt = getopt32(argv, "mbn" USE_FEATURE_IPCALC_FANCY("phs"));
- argc -= optind;
+ opt_complementary = "-1:?2"; /* minimum 1 arg, maximum 2 args */
+ opt = getopt32(argv, "mbn" IF_FEATURE_IPCALC_FANCY("phs"));
argv += optind;
- if (opt & (BROADCAST | NETWORK | NETPREFIX)) {
- if (argc > 2 || argc <= 0)
- bb_show_usage();
- } else {
- if (argc != 1)
+ if (opt & SILENT)
+ logmode = LOGMODE_NONE; /* suppress error_msg() output */
+ opt &= ~SILENT;
+ if (!(opt & (BROADCAST | NETWORK | NETPREFIX))) {
+ /* if no options at all or
+ * (no broadcast,network,prefix) and (two args)... */
+ if (!opt || argv[1])
bb_show_usage();
}
- if (opt & SILENT)
- logmode = LOGMODE_NONE; /* Suppress error_msg() output */
ipstr = argv[0];
if (ENABLE_FEATURE_IPCALC_FANCY) {
while (*prefixstr) {
if (*prefixstr == '/') {
- *prefixstr = (char)0;
- prefixstr++;
+ *prefixstr++ = '\0';
if (*prefixstr) {
unsigned msk;
netprefix = xatoul_range(prefixstr, 0, 32);
prefixstr++;
}
}
- ipaddr = inet_aton(ipstr, &a);
- if (ipaddr == 0) {
+ if (inet_aton(ipstr, &s_ipaddr) == 0) {
bb_error_msg_and_die("bad IP address: %s", argv[0]);
}
- ipaddr = a.s_addr;
- if (argc == 2) {
+ if (argv[1]) {
if (ENABLE_FEATURE_IPCALC_FANCY && have_netmask) {
bb_error_msg_and_die("use prefix or netmask, not both");
}
-
- netmask = inet_aton(argv[1], &a);
- if (netmask == 0) {
+ if (inet_aton(argv[1], &s_netmask) == 0) {
bb_error_msg_and_die("bad netmask: %s", argv[1]);
}
- netmask = a.s_addr;
} else {
-
/* JHC - If the netmask wasn't provided then calculate it */
if (!ENABLE_FEATURE_IPCALC_FANCY || !have_netmask)
netmask = get_netmask(ipaddr);
}
if (opt & NETMASK) {
- printf("NETMASK=%s\n", inet_ntoa((*(struct in_addr *) &netmask)));
+ printf("NETMASK=%s\n", inet_ntoa(s_netmask));
}
if (opt & BROADCAST) {
broadcast = (ipaddr & netmask) | ~netmask;
- printf("BROADCAST=%s\n", inet_ntoa((*(struct in_addr *) &broadcast)));
+ printf("BROADCAST=%s\n", inet_ntoa(s_broadcast));
}
if (opt & NETWORK) {
network = ipaddr & netmask;
- printf("NETWORK=%s\n", inet_ntoa((*(struct in_addr *) &network)));
+ printf("NETWORK=%s\n", inet_ntoa(s_network));
}
if (ENABLE_FEATURE_IPCALC_FANCY) {
hostinfo = gethostbyaddr((char *) &ipaddr, sizeof(ipaddr), AF_INET);
if (!hostinfo) {
- bb_herror_msg_and_die("cannot find hostname for %s", argv[0]);
+ bb_herror_msg_and_die("can't find hostname for %s", argv[0]);
}
str_tolower(hostinfo->h_name);