Emscripten build

.gitattributes

@@ -8,3 +8,4 @@
 /.github/workflows		export-ignore
 /.pre-commit-config.yaml	export-ignore
 /pyproject.toml			export-ignore
+/.vscode			export-ignore

deps/meson.build

@@ -89,21 +89,43 @@ subproject(
     'build_codec_apps=false',
   ],
 )
+
+
+host_system = host_machine.system()
+
+# When trying to do with wasm32,
+# this happen with pcre2, "Problem encountered: Your configuration is not supported"
+
+if host_system != 'emscripten'
 subproject(
   'pcre2',
-  default_options : [
+  default_options: [
     'grep=false',
     'test=false',
   ],
 )
+endif
+
+glib_options = [
+  'introspection=disabled',
+  'nls=disabled',
+  'tests=false',
+]
+if host_system == 'emscripten'
+  glib_options += [
+    'selinux=disabled',
+    'xattr=false',
+    'libmount=disabled',
+    'nls=disabled',
+    'force_fallback_for=pcr2, gvdb',
+  ]
+endif
+
 subproject(
   'glib',
-  default_options : [
-    'introspection=disabled',
-    'nls=disabled',
-    'tests=false',
-  ],
+  default_options : glib_options,
 )
+
 subproject(
   'gdk-pixbuf',
   default_options : [

machines/cross-emscripten.ini

@@ -0,0 +1,29 @@
+[binaries]
+c = 'emcc'
+cpp = 'em++'
+ld = 'wasm-ld'
+ar = 'emar'
+ranlib = 'emranlib'
+#pkgconfig = 'pkg-config'
+
+# https://docs.gtk.org/glib/cross-compiling.html#cross-properties
+[properties]
+growing_stack = true
+have_c99_vsnprintf = true
+have_c99_snprintf = true
+have_unix98_printf = true
+openslide_bin_platform = 'wasm32'
+python_platform_tag = 'wasm32'
+
+[built-in options]
+# Ensure that '-s PTHREAD_POOL_SIZE=*' is not injected into .pc files
+c_thread_count = 0
+cpp_thread_count = 0
+c_args = '-matomics -mbulk-memory'
+cpp_args = '-matomics -mbulk-memory'
+
+[host_machine]
+system = 'emscripten'
+cpu_family = 'wasm32'
+cpu = 'wasm32'
+endian = 'little'

subprojects/gdk-pixbuf.wrap

@@ -7,7 +7,7 @@ source_fallback_url = https://github.com/mesonbuild/wrapdb/releases/download/gdk
 wrapdb_version = 2.42.12-1
 
 # https://gitlab.gnome.org/GNOME/gdk-pixbuf/-/merge_requests/158
-diff_files = gdk-pixbuf-intl.patch
+diff_files = gdk-pixbuf-intl.patch, gdk-pixbuf-gmodule.patch
 
 [provide]
 gdk-pixbuf-2.0 = gdkpixbuf_dep

subprojects/glib.wrap

@@ -1,10 +1,11 @@
 [wrap-file]
 directory = glib-2.80.4
 source_url = https://download.gnome.org/sources/glib/2.80/glib-2.80.4.tar.xz
-source_fallback_url = https://github.com/mesonbuild/wrapdb/releases/download/glib_2.80.4-1/glib-2.80.4.tar.xz
 source_filename = glib-2.80.4.tar.xz
 source_hash = 24e029c5dfc9b44e4573697adf33078a9827c48938555004b3b9096fa4ea034f
+source_fallback_url = https://github.com/mesonbuild/wrapdb/releases/download/glib_2.80.4-1/glib-2.80.4.tar.xz
 wrapdb_version = 2.80.4-1
+diff_files = glib.patch
 
 [provide]
 dependency_names = gthread-2.0, gobject-2.0, gmodule-no-export-2.0, gmodule-export-2.0, gmodule-2.0, glib-2.0, gio-2.0, gio-windows-2.0, gio-unix-2.0

subprojects/libffi.wrap

@@ -6,6 +6,7 @@ source_hash = d66c56ad259a82cf2a9dfc408b32bf5da52371500b84745f7fb8b645712df676
 patch_filename = libffi_3.4.4-4_patch.zip
 patch_url = https://wrapdb.mesonbuild.com/v2/libffi_3.4.4-4/get_patch
 patch_hash = 6babcedb6949383986f1b240a99cd2219a029d62421996d518865a2de855d35a
+diff_files = libffi-wasm-3.4.4.patch
 source_fallback_url = https://github.com/mesonbuild/wrapdb/releases/download/libffi_3.4.4-4/libffi-3.4.4.tar.gz
 wrapdb_version = 3.4.4-4
 

subprojects/packagefiles/gdk-pixbuf-gmodule.patch

@@ -0,0 +1,14 @@
+diff --git a/meson.build b/meson.build
+index 3eb3fcc..c69e4ac 100644
+--- a/meson.build
++++ b/meson.build
+@@ -235,6 +235,9 @@ if gmodule_dep.type_name() == 'pkgconfig'
+ else
+   build_modules = subproject('glib').get_variable('g_module_impl') != '0'
+ endif
++if host_system == 'emscripten'
++  build_modules = false
++endif
+ gdk_pixbuf_conf.set('USE_GMODULE', build_modules)
+
+ # Check which loaders should be built into gdk-pixbuf