From: Ian Jackson <ian@liberator.relativity.greenend.org.uk>
Date: Sun, 22 Aug 2010 18:37:01 +0000 (+0100)
Subject: jpctb: New algorithm for finding java stuff
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~yarrgweb/git?p=jarrg-owen.git;a=commitdiff_plain;h=27ad770787f1e70c9ec77065aa3511b9efc71b2d

jpctb: New algorithm for finding java stuff
---

diff --git a/jpctb b/jpctb
index c5bf4aa..5157a05 100755
--- a/jpctb
+++ b/jpctb
@@ -32,6 +32,12 @@ fail () {
 	echo >&2 "jpctb: $*"
 	exit 127
 }
+
+nojre () {
+	fail "couldn't find the right jre: $*
+ perhaps you should make ypp's java symlink (normally yohoho/java)
+ point to your jre, eg to /usr/lib/jvm/java-6-sun"
+
 badusage () {
 	fail "bad usage: $*"
 }
@@ -73,58 +79,51 @@ fi
 
 yppdir="${yohoho%/*}"
 
+# this replicates the java-searching logic from yohoho/yohoho:
+if [ -x "$yohoho/java/bin/java" ]; then
+	yppjava="$yohoho/java/bin/java"
+elif [ -x "$JAVA_HOME/bin/java" ]; then
+	yppjava="$JAVA_HOME/bin/java"
+else
+	set +e
+	yppjava=`type -p java 2>&1`
+	set -e
+fi
+
 cat <<END
 jpctb:
    jpctb tree:	 "$jpctbdir"
    yohoho:       "$yohoho"
+   ypp uses:     "$yppjava"
 END
 
-if [ -x "$yppdir/java/bin/java" ]; then
-	if [ -d "$yppdir/java/jre" ]; then
-		echo "   yohoho/java/bin and yohoho/java/jre exist, good"
-		javadir="$yppdir/java"
-	else
-		absjava=`readlink -f "$yppdir/java/bin/java"`
-		cat <<END
-   yohoho/java/bin exists but yohoho/java/jre does not
-   abs. java:    "$absjava"
-END
-		case "$absjava" in
-		*/jre/bin/java)
-			echo "   found jre directory, good"
-			javadir="${absjava%/jre/bin/java}"
-			;;
-		*)
-			echo "   java binary not in jre dir as expected, hmm."
-			;;
-		esac
-	fi
+if ! [ -x "$yppjava" ]; then
+	nojre "bad java ypp"
 fi
 
-if [ "x$javadir" = x ] && [ x"$JAVA_HOME" != x ] && \
-   [ -x "$JAVA_HOME/bin/java" ]; then
-cat <<END
-   yohoho/java/bin/java nonexistent or unsuitable, trying JAVA_HOME"
-   JAVA_HOME:    "$JAVA_HOME"
-END
-	if [ -d "$JAVA_HOME/jre" ]; then
-		javadir="$JAVA_HOME"
-	else
-		echo "   JAVA_HOME has no jre subdirectory, hmm."
+javadir="${yppjava#/bin/java}"
+if [ -x "$javadir/jre/bin/java" ]; then
+	echo "   java/ points to the jre, good"
+else
+	echo "   java/ has just the executable bin/java, trying readlink"
+	absjava=`readlink -f "$yppjava"`
+	echo "   abs. java:    \"$absjava\""
+	case "$absjava" in
+	*/jre/bin/java)
+		echo "   found jre directory, good"
+		javadir="${absjava%/jre/bin/java}"
+		;;
+	*)
+		nojre "java binary not in jre dir"
+		;;
+	esac
 	fi
 fi
 
-if [ "x$javadir" = x ]; then
-	fail "could not find java runtime system
- please check that $yppdir/java points to your Java installation"
-fi
-
 case "$javadir" in
-/usr)	fail "javadir is still /usr (and even found /usr/jre!)
- please make $yppdir/java point somewhere more sensible and/or
- reinstall YPP not telling it your java is in /usr.  sorry." ;;
-/*)	;;
-*)	javadir="$PWD/$javadir" ;;
+|/|/usr)	nojre "javadir is $javadir (and even found $javadir/jre!)" ;;
+/*)		;;
+*)		javadir="$PWD/$javadir" ;;
 esac
 
 jtmp="$jpctbdir/tmp"