Add listening support.

diff --git a/applets/usage.c b/applets/usage.c
index 215871b5a27be7a44ea9cdfd533e0e3fd4c7196d..1686910d59052c352bd17c3a875a3a6c4102438e 100644 (file)
--- a/applets/usage.c
+++ b/applets/usage.c
@@ -959,9 +959,13 @@ const char mv_usage[] =
 
 #if defined BB_NC
 const char nc_usage[] =
-       "nc [IP] [port]" 
+       "nc [-p PORT] IP PORT\n"
+       "   or: nc -l -p PORT"
 #ifndef BB_FEATURE_TRIVIAL_HELP
-       "\n\nNetcat opens a pipe to IP:port"
+       "\n\nNetcat opens a pipe to IP:PORT\n"
+       "Options:\n"
+       "\t-l\tListen on the socket.\n"
+       "\t-p PORT\tBind the local port to PORT."
 #endif
        ;
 #endif

diff --git a/docs/busybox.sgml b/docs/busybox.sgml
index 0dc4bffa3ce65e850ae506cbd7a9a339eda671ea..02d85e499fcb8d2fcd10af176aa341e563c10205 100644 (file)
--- a/docs/busybox.sgml
+++ b/docs/busybox.sgml
@@ -2452,7 +2452,12 @@
                </para>
 
                <para>
-               Open a pipe to HOST:PORT.
+                  or: nc -p PORT -l
+               </para>
+
+
+               <para>
+               Open a pipe to HOST:PORT or listen for a connection on PORT.
                </para>
 
                <para>

diff --git a/nc.c b/nc.c
index 682da82bf02037927dee97abde283abe9ea5a43a..3f512d1cb56fe11be546ca88ea11102072697263 100644 (file)
--- a/nc.c
+++ b/nc.c
@@ -41,7 +41,7 @@
 
 int nc_main(int argc, char **argv)
 {
-       int sfd;
+       int do_listen = 0, lport = 0, tmpfd, opt, sfd;
        char buf[BUFSIZ];
 
        struct sockaddr_in address;
@@ -49,24 +49,54 @@ int nc_main(int argc, char **argv)
 
        fd_set readfds, testfds;
 
-       argc--;
-       argv++;
-       if (argc < 2 || **argv == '-') {
-               usage(nc_usage);
+       while ((opt = getopt(argc, argv, "lp:")) > 0) {
+               switch (opt) {
+                       case 'l':
+                               do_listen++;
+                               break;
+                       case 'p':
+                               lport = atoi(optarg);
+                               break;
+                       default:
+                               usage(nc_usage);
+               }
        }
 
+       if ((do_listen && optind != argc) || (!do_listen && optind + 2 != argc))
+               usage(nc_usage);
+
        if ((sfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
                perror_msg_and_die("socket");
 
-       if ((hostinfo = gethostbyname(*argv)) == NULL)
-               error_msg_and_die("cannot resolve %s", *argv);
-
        address.sin_family = AF_INET;
-       address.sin_addr = *(struct in_addr *) *hostinfo->h_addr_list;
-       address.sin_port = htons(atoi(*(++argv)));
 
-       if (connect(sfd, (struct sockaddr *) &address, sizeof(address)) < 0)
-               perror_msg_and_die("connect");
+       if (lport != 0) {
+               memset(&address.sin_addr, 0, sizeof(address.sin_addr));
+               address.sin_port = htons(lport);
+
+               if (bind(sfd, (struct sockaddr *) &address, sizeof(address)) < 0)
+                       perror_msg_and_die("bind");
+       }
+
+       if (do_listen) {
+               if (listen(sfd, 1) < 0)
+                       perror_msg_and_die("listen");
+
+               if ((tmpfd = accept(sfd, (struct sockaddr *) &address, &opt)) < 0)
+                       perror_msg_and_die("accept");
+
+               close(sfd);
+               sfd = tmpfd;
+       } else {
+               if ((hostinfo = gethostbyname(argv[optind])) == NULL)
+                       error_msg_and_die("cannot resolve %s\n", argv[optind]);
+
+               address.sin_addr = *(struct in_addr *) *hostinfo->h_addr_list;
+               address.sin_port = htons(atoi(argv[optind+1]));
+
+               if (connect(sfd, (struct sockaddr *) &address, sizeof(address)) < 0)
+                       perror_msg_and_die("connect");
+       }
 
        FD_ZERO(&readfds);
        FD_SET(sfd, &readfds);

diff --git a/networking/nc.c b/networking/nc.c
index 682da82bf02037927dee97abde283abe9ea5a43a..3f512d1cb56fe11be546ca88ea11102072697263 100644 (file)
--- a/networking/nc.c
+++ b/networking/nc.c
@@ -41,7 +41,7 @@
 
 int nc_main(int argc, char **argv)
 {
-       int sfd;
+       int do_listen = 0, lport = 0, tmpfd, opt, sfd;
        char buf[BUFSIZ];
 
        struct sockaddr_in address;
@@ -49,24 +49,54 @@ int nc_main(int argc, char **argv)
 
        fd_set readfds, testfds;
 
-       argc--;
-       argv++;
-       if (argc < 2 || **argv == '-') {
-               usage(nc_usage);
+       while ((opt = getopt(argc, argv, "lp:")) > 0) {
+               switch (opt) {
+                       case 'l':
+                               do_listen++;
+                               break;
+                       case 'p':
+                               lport = atoi(optarg);
+                               break;
+                       default:
+                               usage(nc_usage);
+               }
        }
 
+       if ((do_listen && optind != argc) || (!do_listen && optind + 2 != argc))
+               usage(nc_usage);
+
        if ((sfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
                perror_msg_and_die("socket");
 
-       if ((hostinfo = gethostbyname(*argv)) == NULL)
-               error_msg_and_die("cannot resolve %s", *argv);
-
        address.sin_family = AF_INET;
-       address.sin_addr = *(struct in_addr *) *hostinfo->h_addr_list;
-       address.sin_port = htons(atoi(*(++argv)));
 
-       if (connect(sfd, (struct sockaddr *) &address, sizeof(address)) < 0)
-               perror_msg_and_die("connect");
+       if (lport != 0) {
+               memset(&address.sin_addr, 0, sizeof(address.sin_addr));
+               address.sin_port = htons(lport);
+
+               if (bind(sfd, (struct sockaddr *) &address, sizeof(address)) < 0)
+                       perror_msg_and_die("bind");
+       }
+
+       if (do_listen) {
+               if (listen(sfd, 1) < 0)
+                       perror_msg_and_die("listen");
+
+               if ((tmpfd = accept(sfd, (struct sockaddr *) &address, &opt)) < 0)
+                       perror_msg_and_die("accept");
+
+               close(sfd);
+               sfd = tmpfd;
+       } else {
+               if ((hostinfo = gethostbyname(argv[optind])) == NULL)
+                       error_msg_and_die("cannot resolve %s\n", argv[optind]);
+
+               address.sin_addr = *(struct in_addr *) *hostinfo->h_addr_list;
+               address.sin_port = htons(atoi(argv[optind+1]));
+
+               if (connect(sfd, (struct sockaddr *) &address, sizeof(address)) < 0)
+                       perror_msg_and_die("connect");
+       }
 
        FD_ZERO(&readfds);
        FD_SET(sfd, &readfds);

diff --git a/usage.c b/usage.c
index 215871b5a27be7a44ea9cdfd533e0e3fd4c7196d..1686910d59052c352bd17c3a875a3a6c4102438e 100644 (file)
--- a/usage.c
+++ b/usage.c
@@ -959,9 +959,13 @@ const char mv_usage[] =
 
 #if defined BB_NC
 const char nc_usage[] =
-       "nc [IP] [port]" 
+       "nc [-p PORT] IP PORT\n"
+       "   or: nc -l -p PORT"
 #ifndef BB_FEATURE_TRIVIAL_HELP
-       "\n\nNetcat opens a pipe to IP:port"
+       "\n\nNetcat opens a pipe to IP:PORT\n"
+       "Options:\n"
+       "\t-l\tListen on the socket.\n"
+       "\t-p PORT\tBind the local port to PORT."
 #endif
        ;
 #endif