Fix analogdevicesinc#307 by accepting avahi null names, and install a…

…vahi service file

This will make sure things like this are functional:

./tests/iio_attr -u ip: -d
IIO context has 5 devices:
	iio:device0: adm1177, found 0 device attributes
	iio:device1: ad9361-phy, found 18 device attributes
	iio:device2: xadc, found 1 device attributes
	iio:device3: cf-ad9361-dds-core-lpc, found 0 device attributes
	iio:device4: cf-ad9361-lpc, found 0 device attributes

Signed-off-by: Robin Getz <[email protected]>

CMakeLists.txt

@@ -218,6 +218,7 @@ endif()
 include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_CURRENT_BINARY_DIR})
 
 if(WITH_NETWORK_BACKEND)
+	message(STATUS "Building with Network back end support")
 	if (WIN32)
 		set(LIBS_TO_LINK ${LIBS_TO_LINK} wsock32 ws2_32)
 	endif()
@@ -244,14 +245,20 @@ if(WITH_NETWORK_BACKEND)
 	find_library(AVAHI_CLIENT_LIBRARIES avahi-client)
 	find_library(AVAHI_COMMON_LIBRARIES avahi-common)
 	if(AVAHI_CLIENT_LIBRARIES AND AVAHI_COMMON_LIBRARIES)
+		message(STATUS "Building with Avahi, a zero-configuration networking (zeroconf) implementation")
 		set(HAVE_AVAHI ON)
 		set(AVAHI_LIBRARIES ${AVAHI_CLIENT_LIBRARIES} ${AVAHI_COMMON_LIBRARIES})
 		set(LIBS_TO_LINK ${LIBS_TO_LINK} ${AVAHI_LIBRARIES})
+		set(AVAHI_SERVICE_INSTALL_DIR /etc/avahi/services/ CACHE PATH "default install path for Avahi service files")
+	else()
+		message(STATUS "Building without Avahi (zeroconf) support")
 	endif()
 
 	set(NEED_THREADS 1)
 	set(IIOD_CLIENT 1)
 	set(NEED_LIBXML2 1)
+else()
+	message(STATUS "Building without network support")
 endif()
 
 # Since libxml2-2.9.2, libxml2 provides its own LibXml2-config.cmake, with all
@@ -300,6 +307,9 @@ endif()
 
 if (IIOD_CLIENT)
 	set(LIBIIO_CFILES ${LIBIIO_CFILES} iiod-client.c)
+	if (HAVE_AVAHI)
+		install(FILES ${CMAKE_CURRENT_SOURCE_DIR}/iio.service DESTINATION ${AVAHI_SERVICE_INSTALL_DIR})
+	endif()
 endif()
 
 configure_file(libiio.iss.cmakein ${CMAKE_CURRENT_BINARY_DIR}/libiio.iss @ONLY)

iio.service

@@ -0,0 +1,34 @@
+<?xml version="1.0" standalone='no'?><!--*-nxml-*-->
+<!DOCTYPE service-group SYSTEM "avahi-service.dtd">
+
+<!--
+  This file is part of avahi.
+
+  avahi is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as
+  published by the Free Software Foundation; either version 2 of the
+  License, or (at your option) any later version.
+
+  avahi is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with avahi; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+  02111-1307 USA.
+-->
+
+<!-- See avahi.service(5) for more information about this configuration file -->
+
+<service-group>
+
+  <name replace-wildcards="yes">%h</name>
+
+  <service>
+    <type>_iio._tcp</type>
+    <port>30431</port>
+  </service>
+
+</service-group>

network.c

@@ -1436,7 +1436,7 @@ struct iio_context * network_create_context(const char *host)
 	hints.ai_socktype = SOCK_STREAM;
 
 #ifdef HAVE_AVAHI
-	if (!host) {
+	if (!host || !host[0]) {
 		char addr_str[AVAHI_ADDRESS_STR_MAX];
 		char port_str[6];
 		AvahiAddress address;