mime-xdg.bbclass: initial add

When opening files by file-browsers on fresh images, user has to choose the
application to open from the pool af ALL known applications even those not
designed to open the file selected. By inheriting this classs in recipes the
assosiations in /usr/share/applications/mimeinfo.cache are build by calling
update-desktop-database.

(From OE-Core rev: 20208d6763e725cea211f933ec1c8e32733a10af)

Signed-off-by: Andreas Müller <schnitzeltony@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes/mime-xdg.bbclass

@@ -0,0 +1,74 @@
+#
+# This class creates mime <-> application associations based on entry 
+# 'MimeType' in *.desktop files
+#
+
+DEPENDS += "desktop-file-utils"
+PACKAGE_WRITE_DEPS += "desktop-file-utils-native"
+DESKTOPDIR = "${datadir}/applications"
+
+# There are recipes out there installing their .desktop files as absolute
+# symlinks. For us these are dangling and cannot be introspected for "MymeType"
+# easily. By addding package-names to MIME_XDG_PACKAGES, packager can force
+# proper update-desktop-database handling. Note that all introspection is
+# skipped for MIME_XDG_PACKAGES not empty
+MIME_XDG_PACKAGES ?= ""
+
+mime_xdg_postinst() {
+if [ "x$D" != "x" ]; then
+	$INTERCEPT_DIR/postinst_intercept update_desktop_database ${PKG} \
+		mlprefix=${MLPREFIX} \
+		desktop_dir=${DESKTOPDIR}
+else
+	update-desktop-database $D${DESKTOPDIR}
+fi
+}
+
+mime_xdg_postrm() {
+if [ "x$D" != "x" ]; then
+	$INTERCEPT_DIR/postinst_intercept update_desktop_database ${PKG} \
+		mlprefix=${MLPREFIX} \
+		desktop_dir=${DESKTOPDIR}
+else
+	update-desktop-database $D${DESKTOPDIR}
+fi
+}
+
+python populate_packages_append () {
+    packages = d.getVar('PACKAGES').split()
+    pkgdest =  d.getVar('PKGDEST')
+    desktop_base = d.getVar('DESKTOPDIR')
+    forced_mime_xdg_pkgs = (d.getVar('MIME_XDG_PACKAGES') or '').split()
+
+    for pkg in packages:
+        desktops_with_mime_found = pkg in forced_mime_xdg_pkgs
+        if d.getVar('MIME_XDG_PACKAGES') == '':
+            desktop_dir = '%s/%s%s' % (pkgdest, pkg, desktop_base)
+            if os.path.exists(desktop_dir):
+                for df in os.listdir(desktop_dir):
+                    if df.endswith('.desktop'):
+                        try:
+                            with open(desktop_dir + '/'+ df, 'r') as f:
+                                for line in f.read().split('\n'):
+                                    if 'MimeType' in line:
+                                        desktops_with_mime_found = True
+                                        break;
+                        except:
+                            bb.warn('Could not open %s. Set MIME_XDG_PACKAGES in recipe or add mime-xdg to INSANE_SKIP.' % desktop_dir + '/'+ df)
+                    if desktops_with_mime_found:
+                        break
+        if desktops_with_mime_found:
+            bb.note("adding mime-xdg postinst and postrm scripts to %s" % pkg)
+            postinst = d.getVar('pkg_postinst_%s' % pkg)
+            if not postinst:
+                postinst = '#!/bin/sh\n'
+            postinst += d.getVar('mime_xdg_postinst')
+            d.setVar('pkg_postinst_%s' % pkg, postinst)
+            postrm = d.getVar('pkg_postrm_%s' % pkg)
+            if not postrm:
+                postrm = '#!/bin/sh\n'
+            postrm += d.getVar('mime_xdg_postrm')
+            d.setVar('pkg_postrm_%s' % pkg, postrm)
+            bb.note("adding desktop-file-utils dependency to %s" % pkg)
+            d.appendVar('RDEPENDS_' + pkg, " " + d.getVar('MLPREFIX')+"desktop-file-utils")
+}

scripts/postinst-intercepts/update_desktop_database

@@ -0,0 +1,8 @@
+#!/bin/sh
+#
+# SPDX-License-Identifier: MIT
+#
+# Post-install intercept for mime-xdg.bbclass
+
+update-desktop-database $D${desktop_dir}
+