wrlib: generate automatically the list of symbols to keep from the API header

Instead of having to maintain manually the map file for LD with the list of
symbols that we want to keep in the WRaster library (the purpose is to hide
internal symbols), this patch implements a script that parses the public
API header and extracts automatically the list of names that are supposed
to be visible to the user.

The goal is to reduce possible human errors, like for example the function
RCombineAlpha that was forgotten from the list, yet still keep the map file
feature which is considered a good practice (it reduces the risk for name
clash and the risk of mis-use of internal stuff from the library).

Signed-off-by: Christophe CURIS <christophe.curis@free.fr>

wrlib/Makefile.am

@@ -5,14 +5,16 @@ DIST_SUBDIRS = $(SUBDIRS) tests
 
 AUTOMAKE_OPTIONS =
 
-EXTRA_DIST = tests libwraster.map get-wraster-flags.in
+EXTRA_DIST = tests get-wraster-flags.in
 
 lib_LTLIBRARIES = libwraster.la
 
 libwraster_la_LDFLAGS = -version-info @WRASTER_VERSION@
 
 if HAVE_LD_VERSION_SCRIPT
-libwraster_la_LDFLAGS += -Wl,--version-script=$(srcdir)/libwraster.map
+libwraster_la_LDFLAGS += -Wl,--version-script=libwraster.map
+EXTRA_libwraster_la_DEPENDENCIES = libwraster.map
+CLEANFILES = libwraster.map
 endif
 
 bin_SCRIPTS = get-wraster-flags
@@ -101,3 +103,8 @@ get-wraster-flags: get-wraster-flags.in Makefile
 	        -e 's#$${XLIBS}#$(XLIBS)#;' < $(abs_srcdir)/get-wraster-flags.in > $@
 	@chmod 755 $@
 
+if HAVE_LD_VERSION_SCRIPT
+libwraster.map: $(include_HEADERS) $(top_srcdir)/script/generate-mapfile-from-header.sh
+	$(AM_V_GEN)$(top_srcdir)/script/generate-mapfile-from-header.sh \
+		-n LIBWRASTER -v $(WRASTER_VERSION) $(srcdir)/$(include_HEADERS) > libwraster.map
+endif

wrlib/libwraster.map

@@ -1,101 +0,0 @@
-/* libwraster.map - libtool symbol version script for libwraster
- * Copyright (c) 2010 Andreas Metzler
- *
- * This file is part of the Raster graphics library
- *
- *  This library is free software; you can redistribute it and/or
- *  modify it under the terms of the GNU Library General Public
- *  License as published by the Free Software Foundation; either
- *  version 2 of the License, or (at your option) any later version.
- *
- *  This library 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
- *  Library General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this library.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-LIBWRASTER3
-{
-  global:
-    RBevelImage;
-    RBlurImage;
-    RClearImage;
-    RCloneImage;
-    RCombineArea;
-    RCombineAreaWithOpaqueness;
-    RCombineImages;
-    RCombineImagesWithOpaqueness;
-    RCombineImageWithColor;
-    RConvertImage;
-    RConvertImageMask;
-    RCopyArea;
-    RCreateContext;
-    RDestroyContext;
-    RCreateImage;
-    RCreateImageFromDrawable;
-    RCreateImageFromXImage;
-    RCreateXImage;
-    RDestroyXImage;
-    RDrawLine;
-    RDrawLines;
-    RDrawSegments;
-    RErrorCode;
-    RFillImage;
-    RGetClosestXColor;
-    RGetImageFileFormat;
-    RGetImageFromXPMData;
-    RGetPixel;
-    RGetSubImage;
-    RGetXImage;
-    RHSVtoRGB;
-    RLightImage;
-    RLoadImage;
-    RMakeCenteredImage;
-    RMakeTiledImage;
-    RMessageForError;
-    ROperateLine;
-    ROperateLines;
-    ROperatePixel;
-    ROperatePixels;
-    ROperateRectangle;
-    ROperateSegments;
-    RPutPixel;
-    RPutPixels;
-    RPutXImage;
-    RReleaseImage;
-    RRenderGradient;
-    RRenderInterwovenGradient;
-    RRenderMultiGradient;
-    RRetainImage;
-    RRGBtoHSV;
-    RRotateImage;
-    RFlipImage;
-    RSaveImage;
-    RScaleImage;
-    RShutdown;
-    RSmoothScaleImage;
-    RSupportedFileFormats;
-
-  local:
-# _edata
-# _end
-# _fini
-# _init
-# __bss_start
-# calculateCombineArea
-# contrib
-# R_CreateXImageMappedPixmap
-# RLoadGIF
-# RLoadJPEG
-# RLoadPNG
-# RLoadPPM
-# RLoadTIFF
-# RLoadXPM
-# RSaveXPM
-# _wraster_change_filter
-# WRasterLibVersion
-    *;
-};