Add libspeechd-module library

for making it simpler to create external spd modules.

Fixes #918

NEWS

@@ -2,6 +2,7 @@ Version 0.12 (unreleased)
 * Add openjtalk module.
 * Add socket activation.
 * Add language and variant parameters to "list voice" command.
+* Add libspeechd-module library for making it simpler to create external spd modules.
 * libspeechd: Simplify buffer management.
 * Fix use of semaphores on MacOS.
 * Fix splitting long UTF-8 sequences.

README.md

@@ -130,10 +130,14 @@ that GPL licensing propagation doesn't apply.
 
 The speech modules are connected to the central server through a pipe with
 a very simple protocol similar to SSIP, in such a way that GPL licensing
-propagation doesn't apply either. To make writing speech modules simpler, some
-module helpers are provided under a BSD-2 license, which can thus be combined
-with essentially any other license. Some more advanced module helpers are also
-provided under LGPLv2.1-or-later, but they are not mandatory.
+propagation doesn't apply either.
+
+To make writing speech modules simpler, a libspeechd_module library is provided
+under a BSD-2 license, which can thus be combined with essentially any other
+license.
+
+Some more advanced module helpers are also provided under LGPLv2.1-or-later, but
+they are not mandatory.
 
 
 

doc/speech-dispatcher.texi

@@ -3044,10 +3044,9 @@ ways to do it.
 Either you can program it all yourself, which is fine as long as you stick to
 the definition of an output module and its communication protocol.
 
-You can also use our @file{module_main.c}, @file{module_readline.c},
-@file{module_process.c}, and @file{module_main.h}, which deal with the
+You can also use our @file{libspeechd_module} library, which deals with the
 communication protocol and other formal things that are common for all modules.
-They are provided under a BSD licence and thus allow to integrate them along
+It is provided under a BSD license and thus allows to integrate it along
 proprietary software. You will have to provide a series of functions, an example
 is provided in @code{src/modules/skeleton0.c}, which can freely serve as a basic
 for your module. You can also read @code{src/modules/skeleton0_espeak-ng*.c},
@@ -3093,9 +3092,8 @@ If you go for the BSD-provided skeleton way, you can start
 with @code{skeleton0.c}. Add the synthesis initialization call
 with default parameters to @code{module_init}, the synchronous
 synthesizing call to @code{module_speak_sync}, and the synthesis
-shutdown call to @code{module_close}. Compile this along
-@file{module_main.c}, @file{module_readline.c}, @file{module_process.c}, and
-@file{module_main.h}. Install this along other modules, and create an empty
+shutdown call to @code{module_close}. Link this with
+@file{libspeechd-module}. Install this along other modules, and create an empty
 configuration file for it. This should already provide you with a working
 module, though with very limited support.
 
@@ -3187,6 +3185,10 @@ accordingly.
 @node The Skeleton of an Output Module, Output Module Functions, How to Write New Output Module, Output Modules
 @subsection The Skeleton of an Output Module
 
+The previous section documented how to write an output module in general. In this
+section, we document the preferred way for writing modules to be shipped with
+speech-dispatcher.
+
 Each output module should include @file{module_utils.h} where the
 SPDMsgSettings structure is defined to be able to handle the different
 speech synthesis settings.  This file also provides tools which help

src/modules/.gitignore

@@ -22,6 +22,7 @@
 /TAGS
 /dummy-message.wav
 /libbaratinoo.so
+/libspeechd_module.la
 /libvoxin.so
 /sd_baratinoo
 /sd_cicero

src/modules/Makefile.am

@@ -21,7 +21,7 @@ EXTRA_DIST = baratinoo_shim.c README.baratinoo
 EXTRA_DIST += kali_Kali_shim.cpp kali_KGlobal_shim.cpp kali_KTrans_shim.cpp kali_KParle_shim.cpp kali_KAnalyse_shim.cpp
 EXTRA_DIST += ibmtts_shim.c eci.h
 EXTRA_DIST += voxin_shim.c voxin.h
-EXTRA_DIST += module_main.h module_utils.h
+EXTRA_DIST += module_utils.h
 EXTRA_DIST += dummy-message-default.wav
 EXTRA_DIST += dummy-message.txt
 CLEANFILES = dummy-message.wav
@@ -37,6 +37,15 @@ AM_CFLAGS = $(ERROR_CFLAGS)
 AM_CXXFLAGS = $(ERROR_CFLAGS)
 AM_CPPFLAGS = $(inc_local) -DDATADIR=\"$(snddatadir)\" $(GLIB_CFLAGS)
 
+#
+# This is the BSD-licensed helper library that people can use to create their
+# own speech-dispatcher module
+#
+spdinclude_HEADERS = module_main.h
+lib_LTLIBRARIES = libspeechd_module.la
+libspeechd_module_la_SOURCES = module_main.c module_readline.c module_process.c
+libspeechd_module_la_LDFLAGS = -version-info 0:0:0
+
 #
 # These are some common helper that speech-dispatcher-provided modules share to
 # process configuration, process ssml, audio, etc.
@@ -54,14 +63,16 @@ module_utils_play_CPPFLAGS = $(AM_CPPFLAGS) \
 # skeleton0 example module
 #
 noinst_PROGRAMS = sd_skeleton0
-sd_skeleton0_SOURCES = skeleton0.c module_main.c module_readline.c module_process.c
+sd_skeleton0_SOURCES = skeleton0.c
+sd_skeleton0_LDADD = libspeechd_module.la
 
 #
 # skeleton example module
 #
 noinst_PROGRAMS += sd_skeleton_config
 sd_skeleton_config_SOURCES = skeleton_config.c $(common_SOURCES)
 sd_skeleton_config_LDADD = $(top_builddir)/src/common/libcommon.la \
+	libspeechd_module.la \
 	$(audio_dlopen_modules) \
 	$(common_LDADD)
 
@@ -173,33 +184,33 @@ install-exec-hook: install-exec-hook-espeak
 # espeak-ng-based skeleton0 example module
 #
 noinst_PROGRAMS += sd_skeleton0_espeak-ng-sync
-sd_skeleton0_espeak_ng_sync_SOURCES = skeleton0_espeak-ng-sync.c module_main.c module_readline.c module_process.c
+sd_skeleton0_espeak_ng_sync_SOURCES = skeleton0_espeak-ng-sync.c
 sd_skeleton0_espeak_ng_sync_CFLAGS = $(ESPEAK_NG_CFLAGS)
-sd_skeleton0_espeak_ng_sync_LDADD = $(ESPEAK_NG_LIBS) $(EXTRA_ESPEAK_LIBS)
+sd_skeleton0_espeak_ng_sync_LDADD = libspeechd_module.la $(ESPEAK_NG_LIBS) $(EXTRA_ESPEAK_LIBS)
 
 #
 # espeak-ng-based skeleton0 example module with asynchronous support
 #
 noinst_PROGRAMS += sd_skeleton0_espeak-ng-async
-sd_skeleton0_espeak_ng_async_SOURCES = skeleton0_espeak-ng-async.c module_main.c module_readline.c module_process.c
+sd_skeleton0_espeak_ng_async_SOURCES = skeleton0_espeak-ng-async.c
 sd_skeleton0_espeak_ng_async_CFLAGS = $(ESPEAK_NG_CFLAGS)
-sd_skeleton0_espeak_ng_async_LDADD = $(ESPEAK_NG_LIBS) $(EXTRA_ESPEAK_LIBS)
+sd_skeleton0_espeak_ng_async_LDADD = libspeechd_module.la $(ESPEAK_NG_LIBS) $(EXTRA_ESPEAK_LIBS)
 
 #
 # espeak-ng-based skeleton0 example module with server audio
 #
 noinst_PROGRAMS += sd_skeleton0_espeak-ng-sync-server
-sd_skeleton0_espeak_ng_sync_server_SOURCES = skeleton0_espeak-ng-sync-server.c module_main.c module_readline.c module_process.c
+sd_skeleton0_espeak_ng_sync_server_SOURCES = skeleton0_espeak-ng-sync-server.c
 sd_skeleton0_espeak_ng_sync_server_CFLAGS = $(ESPEAK_NG_CFLAGS)
-sd_skeleton0_espeak_ng_sync_server_LDADD = $(ESPEAK_NG_LIBS) $(EXTRA_ESPEAK_LIBS)
+sd_skeleton0_espeak_ng_sync_server_LDADD = libspeechd_module.la $(ESPEAK_NG_LIBS) $(EXTRA_ESPEAK_LIBS)
 
 #
 # espeak-ng-based skeleton0 example module with asynchronous support and server audio
 #
 noinst_PROGRAMS += sd_skeleton0_espeak-ng-async-server
-sd_skeleton0_espeak_ng_async_server_SOURCES = skeleton0_espeak-ng-async-server.c module_main.c module_readline.c module_process.c
+sd_skeleton0_espeak_ng_async_server_SOURCES = skeleton0_espeak-ng-async-server.c
 sd_skeleton0_espeak_ng_async_server_CFLAGS = $(ESPEAK_NG_CFLAGS)
-sd_skeleton0_espeak_ng_async_server_LDADD = $(ESPEAK_NG_LIBS) $(EXTRA_ESPEAK_LIBS)
+sd_skeleton0_espeak_ng_async_server_LDADD = libspeechd_module.la $(ESPEAK_NG_LIBS) $(EXTRA_ESPEAK_LIBS)
 endif
 
 #