[glib-networking] meson: allow building as a subproject

[Mathieu Duponchelle <mathieudu src gnome org>]

commit 9c03e2300eeeb2f335d5146328cd2eb8ca0b99e5
Author: Mathieu Duponchelle <mathieu centricular com>
Date:   Mon Mar 26 23:11:45 2018 +0200

    meson: allow building as a subproject
    
    and use fallbacks for the mandatory dependencies
    
    https://bugzilla.gnome.org/show_bug.cgi?id=794709

 meson.build                |   20 ++++++++++++++++----
 proxy/gnome/meson.build    |    2 ++
 proxy/libproxy/meson.build |    2 ++
 tls/gnutls/meson.build     |    2 ++
 tls/pkcs11/meson.build     |    3 +++
 tls/tests/meson.build      |    2 ++
 6 files changed, 27 insertions(+), 4 deletions(-)
---
diff --git a/meson.build b/meson.build
index 1ea400d..4c62023 100644
--- a/meson.build
+++ b/meson.build
@@ -43,11 +43,23 @@ if host_machine.system().contains('linux')
 endif
 
 # *** Check GLib GIO        ***
-glib_dep = dependency('glib-2.0', version: '>= 2.55.1')
-gio_dep = dependency('gio-2.0')
+glib_dep = dependency('glib-2.0', version: '>= 2.55.1',
+  fallback: ['glib', 'libglib_dep'])
+gio_dep = dependency('gio-2.0',
+  fallback: ['glib', 'libgio_dep'])
+gobject_dep = dependency('gio-2.0',
+  fallback: ['glib', 'libgobject_dep'])
+gmodule_dep = dependency('gmodule-2.0',
+  fallback: ['glib', 'libgmodule_dep'])
+
+if glib_dep.type_name() == 'internal'
+  glib_proj = subproject('glib')
+  gio_module_dir = glib_proj.get_variable('glib_giomodulesdir')
+else
+  gio_module_dir = gio_dep.get_pkgconfig_variable('giomoduledir',
+                                                  define_variable: ['libdir', libdir])
+endif
 
-gio_module_dir = gio_dep.get_pkgconfig_variable('giomoduledir',
-                                                define_variable: ['libdir', libdir])
 assert(gio_module_dir != '', 'GIO_MODULE_DIR is missing from gio-2.0.pc')
 
 # *** Checks for LibProxy   ***
diff --git a/proxy/gnome/meson.build b/proxy/gnome/meson.build
index 069a459..ed90537 100644
--- a/proxy/gnome/meson.build
+++ b/proxy/gnome/meson.build
@@ -6,6 +6,8 @@ sources = files(
 deps = [
   gio_dep,
   glib_dep,
+  gmodule_dep,
+  gobject_dep,
   gsettings_desktop_schemas_dep
 ]
 
diff --git a/proxy/libproxy/meson.build b/proxy/libproxy/meson.build
index baa7ab7..95839ae 100644
--- a/proxy/libproxy/meson.build
+++ b/proxy/libproxy/meson.build
@@ -29,6 +29,8 @@ sources = files(
 deps = [
   gio_dep,
   glib_dep,
+  gmodule_dep,
+  gobject_dep,
   libproxy_dep
 ]
 
diff --git a/tls/gnutls/meson.build b/tls/gnutls/meson.build
index 98bbb73..c4f5ef2 100644
--- a/tls/gnutls/meson.build
+++ b/tls/gnutls/meson.build
@@ -16,6 +16,8 @@ incs = [top_inc]
 deps = [
   gio_dep,
   glib_dep,
+  gmodule_dep,
+  gobject_dep,
   gnutls_dep
 ]
 
diff --git a/tls/pkcs11/meson.build b/tls/pkcs11/meson.build
index 5a9523a..94f55d9 100644
--- a/tls/pkcs11/meson.build
+++ b/tls/pkcs11/meson.build
@@ -7,6 +7,9 @@ sources = files(
 
 deps = [
   glib_dep,
+  gio_dep,
+  gmodule_dep,
+  gobject_dep,
   pkcs11_dep
 ]
 
diff --git a/tls/tests/meson.build b/tls/tests/meson.build
index 261fa1e..7aeec87 100644
--- a/tls/tests/meson.build
+++ b/tls/tests/meson.build
@@ -6,6 +6,8 @@ incs = [
 deps = [
   gio_dep,
   glib_dep,
+  gmodule_dep,
+  gobject_dep,
   gnutls_dep
 ]