Split support for libsoup-gnome

Original patch by Romain Perier.
---
--- configure.ac
+++ configure.ac
@@ -72,15 +72,30 @@
 dnl *** Checks for glib ***
 dnl ***********************
 
-AM_PATH_GLIB_2_0(2.30.0,,,gobject gthread gio)
-if test "$GLIB_LIBS" = ""; then
-   AC_MSG_ERROR(GLIB 2.30.0 or later is required to build libsoup)
-fi
-GLIB_CFLAGS="$GLIB_CFLAGS -DG_DISABLE_SINGLE_INCLUDES"
-
-PKG_CHECK_MODULES(XML, libxml-2.0)
-AC_SUBST(XML_CFLAGS)
-AC_SUBST(XML_LIBS)
+PKG_PROG_PKG_CONFIG
+enable_ssl=no
+AC_ARG_WITH(libsoup-system,
+   AS_HELP_STRING([--with-libsoup-system], [Use libsoup system library to build(default=no)]),
+   [with_libsoup_system=$withval], [with_libsoup_system=no])
+if test "$with_libsoup_system" = "no"; then
+	AM_PATH_GLIB_2_0(2.30.0,,,gobject gthread gio)
+	if test "$GLIB_LIBS" = ""; then
+	   AC_MSG_ERROR(GLIB 2.30.0 or later is required to build libsoup)
+	fi
+	GLIB_CFLAGS="$GLIB_CFLAGS -DG_DISABLE_SINGLE_INCLUDES"
+
+	PKG_CHECK_MODULES(XML, libxml-2.0)
+	AC_SUBST(XML_CFLAGS)
+	AC_SUBST(XML_LIBS)
+
+	dnl *******************
+	dnl *** Misc checks ***
+	dnl *******************
+	AC_CHECK_FUNCS(gmtime_r)
+	AC_CHECK_FUNCS(mmap)
+	AC_CHECK_FUNC(socket, , AC_CHECK_LIB(socket, socket))
+fi
+AM_CONDITIONAL(BUILD_LIBSOUP, test $with_libsoup_system = no)
 
 dnl ***********************
 dnl *** Check for Win32 ***
@@ -99,13 +114,6 @@
 AC_MSG_RESULT([$os_win32])
 AM_CONDITIONAL(OS_WIN32, [test $os_win32 = yes])
 
-dnl *******************
-dnl *** Misc checks ***
-dnl *******************
-AC_CHECK_FUNCS(gmtime_r)
-AC_CHECK_FUNCS(mmap)
-AC_CHECK_FUNC(socket, , AC_CHECK_LIB(socket, socket))
-
 dnl *********************
 dnl *** GNOME support ***
 dnl *********************
@@ -130,6 +138,10 @@
 if test $with_gnome != no; then
 	AC_DEFINE(HAVE_GNOME, 1, [Defined if GNOME support is enabled])
 
+	if test $with_libsoup_system != no; then
+		PKG_CHECK_MODULES(LIBSOUP, libsoup-$SOUP_API_VERSION = $VERSION)
+	fi
+
 	PKG_CHECK_MODULES(SQLITE, sqlite3, :, [AC_MSG_ERROR(dnl
 [Could not find sqlite3 devel files:
 
--- libsoup/Makefile.am
+++ libsoup/Makefile.am
@@ -4,15 +4,18 @@
 LIBWS2_32 = -lws2_32
 endif
 
-INCLUDES = 				\
+INCLUDES =
+lib_LTLIBRARIES =
+CLEANFILES =
+
+if BUILD_LIBSOUP
+INCLUDES += 				\
 	-DG_LOG_DOMAIN=\"libsoup\" 	\
 	-I$(top_srcdir)			\
 	$(SOUP_DEBUG_FLAGS)		\
 	$(SOUP_MAINTAINER_FLAGS)	\
 	$(GLIB_CFLAGS)			\
-	$(XML_CFLAGS)			\
-	$(SQLITE_CFLAGS)		\
-	$(GNOME_KEYRING_CFLAGS)
+	$(XML_CFLAGS)
 
 MARSHAL_GENERATED = soup-marshal.c soup-marshal.h
 MKENUMS_GENERATED = soup-enum-types.c soup-enum-types.h
@@ -41,7 +44,7 @@
 
 BUILT_SOURCES = $(MARSHAL_GENERATED) $(MKENUMS_GENERATED)
 
-CLEANFILES = $(MARSHAL_GENERATED) $(MKENUMS_GENERATED)
+CLEANFILES += $(MARSHAL_GENERATED) $(MKENUMS_GENERATED)
 
 libsoupincludedir = $(includedir)/libsoup-2.4/libsoup
 
@@ -94,7 +97,7 @@
 	$(soup_headers)		\
 	soup-enum-types.h
 
-lib_LTLIBRARIES = libsoup-2.4.la
+lib_LTLIBRARIES += libsoup-2.4.la
 
 libsoup_2_4_la_LDFLAGS =	\
 	-version-info $(SOUP_CURRENT):$(SOUP_REVISION):$(SOUP_AGE) -no-undefined
@@ -178,6 +181,7 @@
 	soup-uri-private.h		\
 	soup-value-utils.c		\
 	soup-xmlrpc.c
+endif
 
 if BUILD_LIBSOUP_GNOME
 
@@ -191,6 +195,10 @@
 
 libsoupgnomeincludedir = $(includedir)/libsoup-gnome-2.4/libsoup
 
+INCLUDES += $(LIBSOUP_CFLAGS)		\
+    $(SQLITE_CFLAGS)			\
+    $(GNOME_KEYRING_CFLAGS)
+
 libsoupgnomeinclude_HEADERS =	\
 	soup-cookie-jar-sqlite.h\
 	soup-gnome.h		\
@@ -198,14 +206,24 @@
 
 lib_LTLIBRARIES += libsoup-gnome-2.4.la
 
+if BUILD_LIBSOUP
 libsoup_gnome_2_4_la_LDFLAGS = $(libsoup_2_4_la_LDFLAGS)
+else
+libsoup_gnome_2_4_la_LDFLAGS =		\
+	-version-info $(SOUP_CURRENT):$(SOUP_REVISION):$(SOUP_AGE) -no-undefined
+endif
 
 libsoup_gnome_2_4_la_LIBADD =		\
-	libsoup-2.4.la			\
 	$(GLIB_LIBS)			\
 	$(SQLITE_LIBS)			\
 	$(GNOME_KEYRING_LIBS)
 
+if BUILD_LIBSOUP
+libsoup_gnome_2_4_la_LIBADD += libsoup-2.4.la
+else
+libsoup_gnome_2_4_la_LIBADD += $(LIBSOUP_LIBS)
+endif
+
 libsoup_gnome_2_4_la_SOURCES =		\
 	soup-cookie-jar-sqlite.c	\
 	soup-gnome-features.c		\
@@ -225,6 +243,8 @@
 
 if HAVE_INTROSPECTION
 
+if BUILD_LIBSOUP
+
 # Core library
 gi_soup_files = \
 	$(filter-out soup.h soup-enum-types.% soup-marshal.%,\
@@ -246,20 +266,28 @@
 
 INTROSPECTION_GIRS += Soup-2.4.gir
 
+endif
+
 if BUILD_LIBSOUP_GNOME
 
+if BUILD_LIBSOUP
+SOUP_GIR = Soup-2.4.gir
+else
+SOUP_GIR =
+endif
+
 # GNOME extensions
 gi_soup_gnome_files = $(filter-out soup-gnome.h,\
 		          $(libsoupgnomeinclude_HEADERS) \
 	                  $(filter-out %.h, $(libsoup_gnome_2_4_la_SOURCES)))
-SoupGNOME-2.4.gir: libsoup-gnome-2.4.la Soup-2.4.gir
+SoupGNOME-2.4.gir: libsoup-gnome-2.4.la $(SOUP_GIR)
+SoupGNOME_2_4_gir_INCLUDES = Soup-2.4
 SoupGNOME_2_4_gir_SCANNERFLAGS =			\
 	--identifier-prefix=Soup			\
 	--symbol-prefix=soup				\
-	--c-include "libsoup/soup-gnome.h"		\
-	--include-uninstalled=$(builddir)/Soup-2.4.gir
+	--c-include "libsoup/soup-gnome.h"
 SoupGNOME_2_4_gir_CFLAGS = $(INCLUDES)
-SoupGNOME_2_4_gir_LIBS = libsoup-gnome-2.4.la libsoup-2.4.la
+SoupGNOME_2_4_gir_LIBS = libsoup-gnome-2.4.la
 SoupGNOME_2_4_gir_FILES = $(addprefix $(srcdir)/,$(gi_soup_gnome_files))
 SoupGNOME_2_4_gir_EXPORT_PACKAGES = libsoup-gnome-2.4
 
--- Makefile.am
+++ Makefile.am
@@ -1,7 +1,11 @@
 ## Process this file with automake to produce Makefile.in
 ACLOCAL_AMFLAGS = -I m4
 
-SUBDIRS = libsoup tests docs
+SUBDIRS = libsoup
+
+if BUILD_LIBSOUP
+SUBDIRS += tests docs
+endif
 
 EXTRA_DIST =			\
 	libsoup-2.4.pc.in	\
@@ -14,7 +18,11 @@
 
 pkgconfigdir = $(libdir)/pkgconfig
 
-pkgconfig_DATA = libsoup-2.4.pc
+pkgconfig_DATA =
+
+if BUILD_LIBSOUP
+pkgconfig_DATA += libsoup-2.4.pc
+endif
 
 if BUILD_LIBSOUP_GNOME
 pkgconfig_DATA += libsoup-gnome-2.4.pc