Added new zbeacon class

configure.ac

@@ -90,8 +90,9 @@ AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <zmq.h>],
                [AC_MSG_RESULT([yes])],
                [AC_MSG_ERROR([no. Please specify libzmq installation prefix using --with-libzmq])])
 
-#Whether we are on mingw or not.
+# Platform specific checks
 czmq_on_mingw32="no"
+czmq_on_android="no"
 
 # Host speciffic checks
 AC_CANONICAL_HOST
@@ -126,6 +127,13 @@ case "${host_os}" in
         # Define on Linux to enable all library features
         CPPFLAGS="-D_GNU_SOURCE -DLINUX $CPPFLAGS"
         AC_DEFINE(CZMQ_HAVE_LINUX, 1, [Have Linux OS])
+
+        case "${host_os}" in
+            *android*)
+                AC_DEFINE(CZMQ_HAVE_ANDROID, 1, [Have Android OS])
+                czmq_on_android="yes"
+            ;;
+        esac
         ;;
     *solaris*)
         # Define on Solaris to enable all library features
@@ -184,6 +192,12 @@ esac
 AC_HEADER_STDC
 AC_CHECK_HEADERS(errno.h arpa/inet.h netinet/tcp.h netinet/in.h stddef.h \
 stdlib.h string.h sys/socket.h sys/time.h unistd.h limits.h)
+AC_CHECK_HEADERS([net/if.h net/if_media.h linux/wireless.h], [], [],
+[
+#ifdef HAVE_SYS_SOCKET_H
+# include <sys/socket.h>
+#endif
+])
 
 # Checks for typedefs, structures, and compiler characteristics.
 AC_HEADER_STDBOOL
@@ -204,12 +218,13 @@ if test "x$GCC" = "xyes"; then
 fi
 
 AM_CONDITIONAL(ON_MINGW, test "x$czmq_on_mingw32" = "xyes")
+AM_CONDITIONAL(ON_ANDROID, test "x$czmq_on_android" = "xyes")
 AM_CONDITIONAL(INSTALL_MAN, test "x$czmq_install_man" = "xyes")
 AM_CONDITIONAL(BUILD_DOC, test "x$czmq_build_doc" = "xyes")
 
 # Checks for library functions.
 AC_TYPE_SIGNAL
-AC_CHECK_FUNCS(perror gettimeofday memset)
+AC_CHECK_FUNCS(perror gettimeofday memset getifaddrs freeifaddrs)
 
 AC_OUTPUT(Makefile src/Makefile doc/Makefile src/libczmq.pc)
 

doc/Makefile.am

@@ -1,6 +1,7 @@
 MAN1 =
 MAN3 =
 MAN7 = czmq.7 \
+    zbeacon.7 \
     zclock.7 \
     zctx.7 \
     zfile.7 \

doc/zbeacon.txt

@@ -0,0 +1,135 @@
+zbeacon(7)
+==========
+
+NAME
+----
+zbeacon - LAN service announcement and discovery
+
+SYNOPSIS
+--------
+----
+//  Create a new beacon
+CZMQ_EXPORT zbeacon_t *
+    zbeacon_new (int port_nbr);
+
+//  Destroy a beacon
+CZMQ_EXPORT void
+    zbeacon_destroy (zbeacon_t **self_p);
+
+//  Set broadcast interval in milliseconds (default is 1000 msec)
+CZMQ_EXPORT void
+    zbeacon_set_interval (zbeacon_t *self, int interval);
+
+//  Filter out any beacon that looks exactly like ours
+CZMQ_EXPORT void
+    zbeacon_noecho (zbeacon_t *self);
+
+//  Start broadcasting beacon to peers at the specified interval
+CZMQ_EXPORT void
+    zbeacon_publish (zbeacon_t *self, byte *transmit, size_t size);
+
+//  Stop broadcasting beacons
+CZMQ_EXPORT void
+    zbeacon_silence (zbeacon_t *self);
+
+//  Start listening to other peers; zero-sized filter means get everything
+CZMQ_EXPORT void
+    zbeacon_subscribe (zbeacon_t *self, byte *filter, size_t size);
+
+//  Stop listening to other peers
+CZMQ_EXPORT void
+    zbeacon_unsubscribe (zbeacon_t *self);
+
+//  Get beacon pipe, for polling or receiving messages off
+CZMQ_EXPORT void *
+    zbeacon_pipe (zbeacon_t *self);
+
+//  Return our own IP address as printable string
+CZMQ_EXPORT char *
+    zbeacon_hostname (zbeacon_t *self);
+
+//  Self test of this class
+void
+    zbeacon_test (bool verbose);
+----
+
+DESCRIPTION
+-----------
+
+The zbeacon module implements a peer-to-peer discovery service for local
+networks. A beacon can broadcast and/or capture service announcements
+using UDP messages on the local area network. This implementation uses
+IPv4 UDP broadcasts. You can define the format of your outgoing beacons,
+and set a filter that validates incoming beacons. Beacons are sent and
+received asynchronously in the background. The zbeacon API provides a
+incoming beacons on a ZeroMQ socket (the pipe) that you can configure,
+poll on, and receive messages on. Incoming beacons are always delivered
+as two frames: the ipaddress of the sender (a string), and the beacon
+data itself (binary, as published).
+
+
+EXAMPLE
+-------
+.From zbeacon_test method
+----
+    zbeacon_t *node1 = zbeacon_new (5670);
+    zbeacon_t *node2 = zbeacon_new (5670);
+    zbeacon_t *node3 = zbeacon_new (5670);
+
+    assert (*zbeacon_hostname (node1));
+    assert (*zbeacon_hostname (node2));
+    assert (*zbeacon_hostname (node3));
+
+    zbeacon_set_interval (node1, 250);
+    zbeacon_set_interval (node2, 250);
+    zbeacon_set_interval (node3, 250);
+    zbeacon_noecho (node1);
+    zbeacon_publish (node1, (byte *) "NODE/1", 6);
+    zbeacon_publish (node2, (byte *) "NODE/2", 6);
+    zbeacon_publish (node3, (byte *) "GARBAGE", 7);
+    zbeacon_subscribe (node1, (byte *) "NODE", 4);
+
+    //  Poll on API pipe and on UDP socket
+    zmq_pollitem_t pollitems [] = {
+        { zbeacon_pipe (node1), 0, ZMQ_POLLIN, 0 },
+        { zbeacon_pipe (node2), 0, ZMQ_POLLIN, 0 },
+        { zbeacon_pipe (node3), 0, ZMQ_POLLIN, 0 }
+    };
+    long stop_at = zclock_time () + 1000;
+    while (zclock_time () < stop_at) {
+        long timeout = (long) (stop_at - zclock_time ());
+        if (timeout < 0)
+            timeout = 0;
+        if (zmq_poll (pollitems, 3, timeout * ZMQ_POLL_MSEC) == -1)
+            break;              //  Interrupted
+
+        //  We cannot get messages on nodes 2 and 3
+        assert ((pollitems [1].revents & ZMQ_POLLIN) == 0);
+        assert ((pollitems [2].revents & ZMQ_POLLIN) == 0);
+
+        //  If we get a message on node 1, it must be NODE/2
+        if (pollitems [0].revents & ZMQ_POLLIN) {
+            char *ipaddress = zstr_recv (zbeacon_pipe (node1));
+            char *beacon = zstr_recv (zbeacon_pipe (node1));
+            assert (streq (beacon, "NODE/2"));
+            free (ipaddress);
+            free (beacon);
+        }
+    }
+    //  Stop listening
+    zbeacon_unsubscribe (node1);
+
+    //  Stop all node broadcasts
+    zbeacon_silence (node1);
+    zbeacon_silence (node2);
+    zbeacon_silence (node3);
+
+    //  Destroy the test nodes
+    zbeacon_destroy (&node1);
+    zbeacon_destroy (&node2);
+    zbeacon_destroy (&node3);
+----
+
+SEE ALSO
+--------
+linkczmq:czmq[7]

doc/zclock.txt

@@ -33,15 +33,6 @@ The zclock class provides essential sleep and system time functions, used
 to slow down threads for testing, and calculate timers for polling. Wraps
 the non-portable system calls in a simple portable API.
 
-This class contains some small surprises. Most amazing, win32 did an API
-better than POSIX. The win32 Sleep() call is not only a neat 1-liner, it
-also sleeps for milliseconds, whereas the POSIX call asks us to think in
-terms of nanoseconds, which is insane. I've decided every single man page
-for this library will say "insane" at least once. Anyhow, milliseconds
-are a concept we can deal with. Seconds are too fat, nanoseconds too
-tiny, but milliseconds are just right for slices of time we want to work
-with at the 0MQ scale. zclock doesn't give you objects to work with, we
-like the czmq class model but we're not insane. There, got it in again.
 The Win32 Sleep() call defaults to 16ms resolution unless the system timer
 resolution is increased with a call to timeBeginPeriod() permitting 1ms
 granularity.

doc/zctx.txt

@@ -52,7 +52,7 @@ DESCRIPTION
 The zctx class wraps 0MQ contexts. It manages open sockets in the context
 and automatically closes these before terminating the context. It provides
 a simple way to set the linger timeout on sockets, and configure contexts
-for number of I/O threads. Sets-up signal (interrrupt) handling for the
+for number of I/O threads. Sets-up signal (interrupt) handling for the
 process.
 
 The zctx class has these main features:
@@ -103,8 +103,6 @@ EXAMPLE
     zsocket_connect (s5, "tcp://127.0.0.1:5555");
     zsocket_connect (s6, "tcp://127.0.0.1:5555");
     assert (zctx_underlying (ctx));
-
-    //  Everything should be cleanly closed now
     zctx_destroy (&ctx);
 ----
 

doc/zfile.txt

@@ -8,21 +8,33 @@ zfile - helper functions for working with files.
 SYNOPSIS
 --------
 ----
+//  Return 1 if file exists, else zero
+CZMQ_EXPORT bool
+    zfile_exists (const char *filename);
+
+//  Return size of file, or -1 if not found
+CZMQ_EXPORT ssize_t
+    zfile_size (const char *filename);
+
+//  Return file mode
+CZMQ_EXPORT mode_t
+    zfile_mode (const char *filename);
+
 //  Delete file. Does not complain if the file is absent
 CZMQ_EXPORT int
     zfile_delete (const char *filename);
 
-//  Make directory (maximum one level depending on OS)
-CZMQ_EXPORT int
-    zfile_mkdir (const char *dirname);
+//  Check if file is 'stable'
+CZMQ_EXPORT bool
+    zfile_stable (const char *filename);
 
-//  Return 1 if file exists, else zero
+//  Create a file path if it doesn't exit
 CZMQ_EXPORT int
-    zfile_exists (const char *filename);
+    zfile_mkdir (const char *pathname);
 
-//  Return size of file, or -1 if not found
-CZMQ_EXPORT ssize_t
-    zfile_size (const char *filename);
+//  Remove a file path if empty
+CZMQ_EXPORT int
+    zfile_rmdir (const char *pathname);
 
 //  Self test of this class
 int
@@ -32,7 +44,7 @@ int
 DESCRIPTION
 -----------
 
-The zfile class provides methods to work with files.
+The zfile class provides methods to work with files and directories.
 
 
 EXAMPLE
@@ -43,7 +55,7 @@ EXAMPLE
     assert (rc == -1);
 
     rc = zfile_exists ("nosuchfile");
-    assert (rc == FALSE);
+    assert (rc != true);
 
     rc = (int) zfile_size ("nosuchfile");
     assert (rc == -1);