libsuricata-config: program to print build flags

Following the pattern of many other libraries, provide a -config
program to output cflags and libs to properly link an application
against the library.

usage: libsuricata-config [--cflags] [--libs] [--static]

--cflags and --libs can be used infividually or together.

--static will link against the static libraries instead of the
shared library. Note that if the shared library is not available,
the static libraries will be provided even without this option.

.gitignore

@@ -65,3 +65,5 @@ test.sh
 .vscode/*
 /suricata-update/*
 !/suricata-update/Makefile.am
+/libsuricata-config
+!/libsuricata-config.in

Makefile.am

@@ -58,3 +58,4 @@ endif
 install-library:
 	cd src && $(MAKE) $@
 	cd rust && $(MAKE) $@
+	$(INSTALL) libsuricata-config "$(DESTDIR)$(bindir)/libsuricata-config"

configure.ac

@@ -2680,6 +2680,7 @@ AC_SUBST(PACKAGE_VERSION)
 AC_SUBST(RUST_FEATURES)
 AC_SUBST(RUST_SURICATA_LIBDIR)
 AC_SUBST(RUST_SURICATA_LIBNAME)
+AC_SUBST(enable_non_bundled_htp)
 
 AM_CONDITIONAL([BUILD_SHARED_LIBRARY], [test "x$enable_shared" = "xyes"] && [test "x$can_build_shared_library" = "xyes"])
 
@@ -2690,6 +2691,7 @@ AC_CONFIG_FILES(contrib/Makefile contrib/file_processor/Makefile contrib/file_pr
 AC_CONFIG_FILES(suricata.yaml etc/Makefile etc/suricata.logrotate etc/suricata.service)
 AC_CONFIG_FILES(python/Makefile python/suricata/config/defaults.py)
 AC_CONFIG_FILES(ebpf/Makefile)
+AC_CONFIG_FILES(libsuricata-config)
 AC_OUTPUT
 
 SURICATA_BUILD_CONF="Suricata Configuration:

libsuricata-config.in

@@ -0,0 +1,66 @@
+#! /bin/sh
+
+prefix="@prefix@"
+exec_prefix="@exec_prefix@"
+includedir="@includedir@"
+libdir="@libdir@"
+LIBS="@LIBS@ @RUST_LDADD@"
+
+shared_lib="-lsuricata"
+static_lib="-lsuricata_c -lsuricata_rust"
+
+enable_non_bundled_htp="@enable_non_bundled_htp@"
+
+lib="$shared_lib"
+
+show_libs="no"
+show_cflags="no"
+use_static="no"
+
+if [ "$#" = 0 ]; then
+    echo "usage: suricata-config [--cflags] [--libs] [--static]"
+    exit 0
+fi
+
+while [ "$#" != 0 ]
+do
+    case "$1" in
+        --libs)
+            show_libs="yes"
+            ;;
+        --cflags)
+            show_cflags="yes"
+            ;;
+        --static)
+            lib="$static_lib"
+            use_status="yes"
+            ;;
+    esac
+    shift
+done
+
+# If --static wasn't provided, use the static library if the shared
+# library is not available.
+if [ "$use_static" = "no" ]; then
+    if ! test -e "$libdir/libsuricata.so"; then
+        lib="$static_lib"
+    fi
+fi
+
+# If we're using a bundled htp, add it to the libs as well. It will
+# already be present if we're use a non-bundled libhtp.
+if [ "$enable_non_bundled_htp" = "no" ]; then
+    lib="${lib} -lhtp"
+fi
+
+output=""
+
+if [ "$show_cflags" = "yes" ]; then
+    output="${output} -DHAVE_CONFIG_H -I$includedir/suricata"
+fi
+
+if [ "$show_libs" = "yes" ]; then
+    output="${output} -L$libdir $lib $LIBS"
+fi
+
+echo "$output"