[RFC] Introduce git-xxdiff to invoke xxdiff for manual conflict resolution

[Martin Langhoff <martin@catalyst.net.nz>]

This is a bit of a crude but really useful shortcut for conflict resolution.
The name is bad, but git-merge-* is a different 'namespace', and git-resolve is
also taken.

And as different conflict resolvers take different options, it may make sense
to have git-xxdiff, git-sdiff and git-winmerge at least initially.

Signed-off-by: Martin Langhoff <martin@catalyst.net.nz>
---
 Makefile      |    2 +-
 git-xxdiff.sh |   38 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 39 insertions(+), 1 deletions(-)

diff --git a/Makefile b/Makefile
index 8349e3d..a6f6628 100644
--- a/Makefile
+++ b/Makefile
@@ -145,7 +145,7 @@ SCRIPT_SH = \
 	git-applymbox.sh git-applypatch.sh git-am.sh \
 	git-merge.sh git-merge-stupid.sh git-merge-octopus.sh \
 	git-merge-resolve.sh git-merge-ours.sh \
-	git-lost-found.sh git-quiltimport.sh
+	git-lost-found.sh git-quiltimport.sh git-xxdiff.sh
 
 SCRIPT_PERL = \
 	git-archimport.perl git-cvsimport.perl git-relink.perl \
diff --git a/git-xxdiff.sh b/git-xxdiff.sh
new file mode 100755
index 0000000..d562ab2
--- /dev/null
+++ b/git-xxdiff.sh
@@ -0,0 +1,38 @@
+#!/bin/sh
+
+USAGE='<path>'
+SUBDIRECTORY_OK=No
+. git-sh-setup
+
+FILE=$1
+MERGE_HEAD=`git rev-parse MERGE_HEAD`
+
+# Sanity checks
+if test ! -n "$FILE"
+then
+	echo Need a path
+	exit 1
+fi
+
+if test ! -n "$MERGE_HEAD"
+then
+	echo git-xxdiff is only useful during a merge
+fi
+
+git cat-file blob HEAD:$FILE > $FILE~HEAD
+if test $? -gt 0
+then 
+	echo "Error - maybe $FILE is not tracked by git?"
+	exit
+fi
+echo Written $FILE~HEAD
+
+git cat-file blob $MERGE_HEAD:$FILE > $FILE~MERGE_HEAD
+if  test $? -gt 0
+then 
+	echo "Error - maybe $FILE is not tracked by git?"
+	exit
+fi
+echo Written $FILE~MERGE_HEAD
+
+xxdiff -wbB --show-merged-pane --merged-filename $FILE~merged $FILE~HEAD $FILE~MERGE_HEAD
\ No newline at end of file
-- 
1.4.2.rc2.g1869bc-dirty