xbps-triggers: add openjdk-profile trigger

This removes the need for each openjdk package to provide their own
/etc/profile.d entry, and fixes the conflict caused by each providing
their own.

Manual.md

@@ -62,6 +62,7 @@ packages for XBPS, the `Void Linux` native packaging system.
 		* [kernel-hooks](#triggers_kernel_hooks)
 		* [mimedb](#triggers_mimedb)
 		* [mkdirs](#triggers_mkdirs)
+		* [openjdk-profile](#triggers_openjdk_profile)
 		* [pango-modules](#triggers_pango_module)
 		* [pycompile](#triggers_pycompile)
 		* [register-shell](#triggers_register_shell)
@@ -2000,6 +2001,13 @@ During removal it will delete the directory using `rmdir`.
 To include this trigger use the `make_dirs` variable, as the trigger won't do anything
 unless it is defined.
 
+<a id="triggers_openjdk_profile"></a>
+#### openjdk-profile
+
+The openjdk-profile trigger is responsible for creating an entry in /etc/profile.d that
+sets the `JAVA_HOME` environment variable to the currently-selected alternative for
+`/usr/bin/java` on installation. This trigger must be manually requested.
+
 <a id="triggers_pango_module"></a>
 #### pango-modules
 

srcpkgs/xbps-triggers/files/openjdk-profile

@@ -0,0 +1,39 @@
+#!/bin/sh
+#
+# Adds an entry to /etc/profile.d for setting $JAVA_HOME.
+#
+# Arguments:	$ACTION = [run/targets]
+#		$TARGET = [post-install/pre-remove]
+#		$PKGNAME
+#		$VERSION
+#		$UPDATE = [yes/no]
+#
+ACTION="$1"
+TARGET="$2"
+PKGNAME="$3"
+VERSION="$4"
+UPDATE="$5"
+
+jdkprofile=etc/profile.d/openjdk.sh
+
+case "$ACTION" in
+targets)
+	echo "post-install"
+	;;
+run)
+	[ -f "$jdkprofile" ] && exit 0
+
+	cat > "$jdkprofile" <<'EOF'
+if _java_bin=$(readlink -e /usr/bin/java); then
+	_java_bin="${_java_bin%/bin/java}"
+	[ -d "${_java_bin}" ] && export JAVA_HOME="${JAVA_HOME:=${_java_bin}}"
+fi
+unset _java_bin
+EOF
+	;;
+*)
+	exit 1
+	;;
+esac
+
+exit 0

srcpkgs/xbps-triggers/template

@@ -1,6 +1,6 @@
 # Template file for 'xbps-triggers'
 pkgname=xbps-triggers
-version=0.121
+version=0.122
 revision=1
 bootstrap=yes
 short_desc="XBPS triggers for Void Linux"