Mega Code Archive
Convert IP address to its base10 form
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#include <stdio.h>
#include <getopt.h>
#include <sys/types.h>
#include <locale.h>
#include <regex.h>
#define PACKAGE "ip2b10"
#define VERSION "0.0.2"
#define URL "WWW"
#define IPEXPR "([0-9]{1,3})\\.([0-9]{1,3})\\.([0-9]{1,3})\\.([0-9]{1,3})"
/* status epilepticus, print help and exit with exval */
void print_help(int exval);
/* print version and exit with exval */
void print_version(int exval);
int main(int argc, char *argv[]) {
regex_t re;
int opt = 0;
int print_flag = 0;
long unsigned int result = 0;
int var1 = 0, var2 = 0;
int var3 = 0, var4 = 0;
/* any options given ? */
if(argc == 1)
print_help(1);
/* option parser */
while((opt = getopt(argc, argv, "hvxa")) != -1) {
switch(opt) {
case 'h': /* print this help and exit */
print_help(0);
case 'v': /* print program version and exit */
print_version(0);
case 'x': /* output in Hex.. */
print_flag = 1;
break;
case 'a': /* output some additional info... */
print_flag = 2;
break;
case '?': /* no such option */
fprintf(stderr, "%s: Error - No such option: `%c'\n\n", PACKAGE, optopt);
print_help(1);
}
}
/* enough options left ? */
if((argc - optind) == 0)
print_help(1);
/* compile regular expression */
if(regcomp(&re, IPEXPR, REG_EXTENDED) != 0) {
fprintf(stderr, "%s: Error - compiling regular expression..\n",
PACKAGE);
return 1;
}
/* while parsing remaining opts.. */
for(; optind < argc; optind++) {
/* very basic test of ip4 dotted quad address format */
if(regexec(&re, argv[optind], 0, NULL, 0) != 0) {
fprintf(stderr, "%s: Error - `%s'; not a ip4 dotted quad..\n",
PACKAGE, argv[optind]);
continue;
}
/* read address */
sscanf(argv[optind], "%d.%d.%d.%d", &var1, &var2, &var3, &var4);
/* convert address to base 10 */
result = (var1 << 24) + (var2 << 16) + (var3 << 8) + var4;
/* output the results */
if(print_flag == 0)
printf("%lu\n", result);
else if(print_flag == 1)
printf("%0lx\n", result);
else {
printf("%%\n");
printf("ip addr : %s\n", argv[optind]);
printf("formula : %d * (256^3) + %d * (256^2) + %d * 256 + %d\n",
var1, var2, var3, var4);
printf("base10 : %lu\n", result);
printf("hex : %0lx\n", result);
}
}
return 0;
}
/* status epilepticus, print help and exit with exval */
void print_help(int exval) {
printf("%s,%s convert an IP address to its base10 form\n", PACKAGE, VERSION);
printf("Usage: %s [-h] [-v] [-x] [-a] IP IP..\n\n", PACKAGE);
printf(" -h print this help and exit\n");
printf(" -v print version and exit\n");
printf(" -x print address in Hexadecimal\n");
printf(" -a print additional info\n\n");
printf(" Please note, this is valid for IP version 4 addresses only!\n");
exit(exval);
}
/* print version and exit with exval */
void print_version(int exval) {
exit(exval);
}
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