-r option for random port number in ldns-fake-server

diff --git a/examples/ldns-fake-server.c b/examples/ldns-fake-server.c
index 8e5c2517b049325c8552f59b5a1fb63fc30d8207..422f36ed1d8298e264196ecea623bb4f545abb6c 100644 (file)
--- a/examples/ldns-fake-server.c
+++ b/examples/ldns-fake-server.c
@@ -35,6 +35,7 @@ void usage(FILE *output)
        fprintf(output, "-h\tshow this help\n");
        fprintf(output, "-i\tigore query completely, just send the next answer on any udp packet\n");
        fprintf(output, "-l\tloop over answers in answer file\n");
+       fprintf(output, "-r\tuse a random port number, all output will be repressed, and only\n\ttheused port will be printed to stdout.\n");
        fprintf(output, "-v <int>\tset verbosity (0-4, default 1)\n");
 }
 
@@ -312,13 +313,32 @@ int run_fake_server(int port,
        }
 
        sock_server->sin_family = AF_INET;
-       sock_server->sin_port = (in_port_t) htons((uint16_t) port);
        sock_server->sin_addr.s_addr = htonl(INADDR_ANY);
+
+       if (port > 0) {
+               sock_server->sin_port = (in_port_t) htons((uint16_t) port);
        
-       if ( bind(s, (struct sockaddr *) sock_server, socklen ) == -1) {
-               perror("bind()");
-               free(sock_server);
-               return -1;
+               if ( bind(s, (struct sockaddr *) sock_server, socklen ) == -1) {
+                       perror("bind()");
+                       free(sock_server);
+                       return -1;
+               }
+       } else {
+               while (1) {
+                       port = (random() % 64510) + 1025;
+                       sock_server->sin_port = (in_port_t) htons((uint16_t) port);
+                       if ( bind(s, (struct sockaddr *) sock_server, socklen ) == -1) {
+                               if (errno != EADDRINUSE) {
+                                       perror("bind()");
+                                       free(sock_server);
+                                       return -1;
+                               }
+                       } else {
+                               printf("%d\n", port);
+                               fflush(stdout);
+                               break;
+                       }
+               }
        }
 
        sock_client = (struct sockaddr_in *) malloc( socklen );
@@ -411,7 +431,7 @@ int main(int argc, char **argv)
 
        /* command line settings */
        char *answer_file;
-       int port;
+       int port = -1;
        int verbosity = 1;
 
        /* internal vars */
@@ -423,7 +443,7 @@ int main(int argc, char **argv)
 
        int result;
        
-       while ((c = getopt(argc, argv, "chilv:")) != -1) {
+       while ((c = getopt(argc, argv, "chilp:rv:")) != -1) {
                switch (c) {
                        case 'c':
                                if (ignore_query) {
@@ -446,23 +466,44 @@ int main(int argc, char **argv)
                        case 'l':
                                loop = true;
                                break;
+                       case 'p':
+                               if (port > -1) {
+                                       usage(stderr);
+                                       exit(EXIT_FAILURE);
+                               }
+                               port = atoi(optarg);
+                               if (port < 1 || port > 65535) {
+                                       fprintf(stderr, "Bad port number\n");
+                                       exit(EXIT_FAILURE);
+                               }
+                               break;
+                       case 'r':
+                               if (port > -1) {
+                                       usage(stderr);
+                                       exit(EXIT_FAILURE);
+                               }
+                               port = 0;
+                               verbosity = 0;
+                               break;
                        case 'v':
                                verbosity = atoi(optarg);
+                               break;
                }
        }
        argc -= optind;
        argv += optind;
        
-       if (argc < 3) {
+       if (argc < 1) {
+               fprintf(stderr, "Too few arguments\n\n");
                usage(stdout);
                exit(EXIT_FAILURE);
        } else {
-               port = atoi(argv[1]);
-               if (port < 1) {
-                       usage(stdout);
-                       exit(EXIT_FAILURE);
-               }
-               answer_file = argv[2];
+               answer_file = argv[0];
+       }
+       
+       if (port < 0) {
+               fprintf(stderr, "No port given\n");
+               exit(EXIT_FAILURE);
        }
 
        answer_count = read_answer_file(pkt_list, pkt_sizes, answer_file);