adding libgap.pc generation and installation, to be used with pkg-con…

…fig (#5080)

.github/workflows/CI.yml

@@ -162,7 +162,7 @@ jobs:
  - uses: gap-actions/setup-cygwin@v1
  if: ${{ runner.os == 'Windows' }}
  with:
- PKGS_TO_INSTALL: 'wget,git,gcc-g++,gcc-core,m4,libgmp-devel,make,automake,libtool,autoconf,autoconf2.5,zlib-devel,libreadline-devel,libmpc-devel,libmpfr-devel,xdg-utils'
+ PKGS_TO_INSTALL: 'wget,git,gcc-g++,gcc-core,m4,libgmp-devel,make,automake,libtool,autoconf,autoconf2.5,zlib-devel,libreadline-devel,libmpc-devel,libmpfr-devel,xdg-utils,pkg-config'
 
  # There are two cygwin installs on github actions (ours,
  # and a preinstalled one which we can't use as not enough packages are installed.
@@ -228,8 +228,9 @@ jobs:
  fi
  sudo apt-get update
  sudo apt-get install --no-install-recommends "${packages[@]}"
+ sudo apt-get install pkg-config
  elif [ "$RUNNER_OS" == "macOS" ]; then
- brew install gmp zlib
+ brew install gmp zlib pkg-config
  fi
  python -m pip install gcovr
 

.gitignore

@@ -13,6 +13,7 @@
 /confdefs.h
 /conftest*
 /libtool
+/libgap.pc
 /src/config.h.in
 /src/config.h.in~
 

Makefile.rules

@@ -532,6 +532,7 @@ clean:
  rm -f bin/gap.sh sysinfo.gap*
  rm -f gap$(EXEEXT) gac ffgen
  rm -f libgap.la
+ rm -f libgap.pc
  rm -rf .libs
  rm -f doc/wsp.g
  rm -f cnf/GAP-*
@@ -656,10 +657,12 @@ install-headers: $(FFDATA_H) build/version.h
  # Create a symlink to support packages using `#include "src/compiled.h"`
  ln -sfn . $(DESTDIR)$(includedir)/gap/src
 
-install-libgap: libgap.la
+install-libgap: libgap.la libgap.pc
  @echo "Warning, 'make install-libgap' is incomplete"
  $(INSTALL) -d -m 0755 $(DESTDIR)$(libdir)
  $(LTINSTALL) -s libgap.la $(DESTDIR)$(libdir)
+ $(INSTALL) -d -m 0755 $(DESTDIR)$(libdir)/pkgconfig
+ $(INSTALL) -m 0644 libgap.pc $(DESTDIR)$(libdir)/pkgconfig
 
 
 .PHONY: install install-bin install-doc install-gaproot install-headers install-libgap
@@ -1258,6 +1261,28 @@ testlibgap: ${LIBGAPTESTS}
  $(v) -A -l $(top_srcdir) -q -T --nointeract >$(v).out && \
  diff $(top_srcdir)/$(v).expect $(v).out && ) :
 
+# test libgap's pkg-config's libgap version reporting
+testpkgconfigversion: install-libgap
+ifeq ($(shell PKG_CONFIG_PATH=$(DESTDIR)$(libdir)/pkgconfig pkg-config --modversion libgap), $(PACKAGE_VERSION))
+ @echo "pkg-config reports correct version of libgap: "$(PACKAGE_VERSION)
+else
+ @echo "pkg-config does not report version of libgap, or is not installed"
+ exit 1
+endif
+
+# test libgap's pkg-config's libgap flags fetching
+testpkgconfigbuild: install-libgap install-headers
+ $(eval PKG_REPORTED_CFLAGS := $(shell PKG_CONFIG_PATH=$(DESTDIR)$(libdir)/pkgconfig pkg-config --cflags libgap | cut -d' ' -f 1)/gap)
+ $(eval PKG_REPORTED_LDFLAGS := $(shell PKG_CONFIG_PATH=$(DESTDIR)$(libdir)/pkgconfig pkg-config --libs libgap))
+ $(eval v := "tst/testlibgap/basic")
+ $(eval com := "tst/testlibgap/common")
+ $(CC) -c $(v).c -o $(v).o $(PKG_REPORTED_CFLAGS)
+ $(CC) -c $(com).c -o $(com).o $(PKG_REPORTED_CFLAGS)
+ $(QUIET_LINK)$(LINK) $(v).o -o $(v) $(com).o $(PKG_REPORTED_LDFLAGS)
+ $(v) -A -l $(top_srcdir) -q -T --nointeract >$(v).out && \
+ diff $(top_srcdir)/$(v).expect $(v).out
+
+
 KERNELTESTS := $(addprefix tst/testkernel/,dstruct)
 
 # run a test in tst/testkernel
@@ -1279,6 +1304,7 @@ testkernel: ${KERNELTESTS}
 
 .PHONY: testinstall testmanuals testobsoletes teststandard testbugfix
 .PHONY: testpackage testpackages testpackagesload testpackagesvars
+.PHONY: testpkgconfigbuild testpkgconfigversion
 .PHONY: check
 
 ########################################################################
@@ -1469,6 +1495,9 @@ build/stamp-h: $(srcdir)/src/config.h.in config.status
  $(SHELL) ./config.status build/config.h
  echo > $@
 
+libgap.pc: $(srcdir)/libgap.pc.in config.status
+ @$(SHELL) ./config.status $@
+
 ifneq ($(MAINTAINER_MODE),no)
 $(srcdir)/src/config.h.in: $(configure_deps)
  @if command -v autoheader >/dev/null 2>&1 ; then \

configure.ac

@@ -1027,6 +1027,7 @@ AC_SUBST([GAP_DEFINES], [$GAP_DEFINES])
 
 AC_CONFIG_FILES([GNUmakefile])
 AC_CONFIG_FILES([CITATION])
+AC_CONFIG_FILES([libgap.pc])
 AC_CONFIG_FILES([doc/make_doc], [chmod +x doc/make_doc])
 AC_CONFIG_FILES([doc/versiondata])
 AC_OUTPUT

dev/ci.sh

@@ -236,6 +236,7 @@ GAPInput
  test -f $GAPPREFIX/include/gap/version.h
  test -f $GAPPREFIX/include/gap/src/compiled.h # for backwards compatibility
  test -f $GAPPREFIX/lib/gap/sysinfo.gap
+ test -f $GAPPREFIX/lib/pkgconfig/libgap.pc
  test -f $GAPPREFIX/share/gap/doc/ref/chap0_mj.html
  test -f $GAPPREFIX/share/gap/grp/basic.gd
  test -f $GAPPREFIX/share/gap/hpcgap/lib/hpc/tasks.g
@@ -257,6 +258,12 @@ GAPInput
  # TODO: should we install the GAP test suite???
  cp -R $SRCDIR/tst $GAPPREFIX/share/gap/
  $GAPPREFIX/bin/gap $GAPPREFIX/share/gap/tst/testinstall.g
+
+ # test integration with pkg-config
+ cd "$SRCDIR"
+ # make install # might be actually needed for testpkgconfigbuild
+ make testpkgconfigversion
+ make testpkgconfigbuild
  ;;
 
  testmanuals)

libgap.pc.in

@@ -0,0 +1,11 @@
+prefix=@prefix@
+exec_prefix=@exec_prefix@
+libdir=@libdir@
+includedir=@prefix@/include
+
+Name: GAP
+Description: Library containing the kernel of GAP, a computer algebra system
+URL: https://www.gap-system.org
+Version: @GAP_VERSION@
+Libs: -L${libdir} -lgap
+Cflags: -I${includedir}