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#include "client/addr.h"
#include "client/client.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/select.h>
#define DEFAULT_PORT 53
static void help() {
printf("wig: a simple dns client\n");
printf("usage: wig [@server] [options] domain [qtype]\n");
printf("arguments: \n");
printf("\t@server\t specify a dns server (@example.com)\n");
printf("\t-p\t specify a port (-p 2000)\n");
printf("\t-t\t force dns request to do tcp first\n");
exit(EXIT_SUCCESS);
}
static void parse_server (char* argv, char** server) {
if (*server != NULL) {
printf("error: only one dns server argument is allowed\n");
exit(EXIT_FAILURE);
}
if (strlen(argv) < 1) {
printf("error: dns server argument cannot be empty\n");
exit(EXIT_FAILURE);
}
*server = argv;
}
static int parse_arguent (int argc, char** argv, Options* options) {
if (strlen(argv[0]) < 2) {
printf("error: expected option after -\n");
exit(EXIT_FAILURE);
}
if (strcmp(argv[0], "-p") == 0) {
if (argc < 2) {
printf("error: expected port after -p\n");
exit(EXIT_FAILURE);
}
if ((options->port = strtoul(argv[1], NULL, 10)) == 0) {
printf("error: %s is not a valid port\n", argv[1]);
exit(EXIT_FAILURE);
}
return 1;
} else if (strcmp(argv[0], "-t") == 0) {
options->force_tcp = true;
return 0;
} else if (
strcmp(argv[0], "-h") == 0 ||
strcmp(argv[0], "--help") == 0
) {
help();
}
printf("error: unkown option %s\n", argv[0]);
exit(EXIT_FAILURE);
}
int main(int argc, char** argv) {
if (argc < 1) return EXIT_FAILURE;
int dargs = 1;
char* server = NULL;
Options options;
options.port = DEFAULT_PORT;
options.force_tcp = false;
for (int i = 1; i < argc; i++) {
char s = argv[i][0];
if (s == '@') {
dargs++;
parse_server(argv[i] + 1, &server);
} else if (s == '-') {
int o = parse_arguent(argc - i, &argv[i], &options);
dargs++;
dargs += o;
i += o;
} else {
break;
}
}
if (argc - dargs < 1) {
printf("usage: wig [@server] [options] domain [qtype]\n");
return EXIT_FAILURE;
}
IpAddr addr;
if (server != NULL) {
if (!ip_addr_name(server, &addr)) {
printf("error: %s is not a valid domain\n", server);
exit(EXIT_FAILURE);
}
} else {
resolve_default_server(&addr);
}
Question* arr;
uint8_t len;
resolve_questions(argc - dargs, &argv[dargs], &len, &arr);
resolve(addr, options, arr, len);
return EXIT_SUCCESS;
}
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