Introduce usagef() that takes a printf-style format

diff --git a/git-merge-one-file.sh b/git-merge-one-file.sh
index e1eb9632660146396a0b5f3f2a410d8cb027ff9d..d067894bf45fd0a50513e196ea2a5e671d901681 100755 (executable)
--- a/git-merge-one-file.sh
+++ b/git-merge-one-file.sh
@@ -16,6 +16,18 @@
 # been handled already by git read-tree, but that one doesn't
 # do any merges that might change the tree layout.
 
+USAGE='<orig blob> <our blob> <their blob> <path>'
+USAGE="$USAGE <orig mode> <our mode> <their mode>"
+LONG_USAGE="Usage: git merge-one-file $USAGE
+
+Blob ids and modes should be empty for missing files."
+
+if ! test "$#" -eq 7
+then
+       echo "$LONG_USAGE"
+       exit 1
+fi
+
 case "${1:-.}${2:-.}${3:-.}" in
 #
 # Deleted in both or deleted in one and unchanged in the other
@@ -113,6 +125,10 @@ case "${1:-.}${2:-.}${3:-.}" in
        src1=`git-unpack-file $2`
        git merge-file "$src1" "$orig" "$src2"
        ret=$?
+       msg=
+       if [ $ret -ne 0 ]; then
+               msg='content conflict'
+       fi
 
        # Create the working tree file, using "our tree" version from the
        # index, and then store the result of the merge.
@@ -120,7 +136,10 @@ case "${1:-.}${2:-.}${3:-.}" in
        rm -f -- "$orig" "$src1" "$src2"
 
        if [ "$6" != "$7" ]; then
-               echo "ERROR: Permissions conflict: $5->$6,$7."
+               if [ -n "$msg" ]; then
+                       msg="$msg, "
+               fi
+               msg="${msg}permissions conflict: $5->$6,$7"
                ret=1
        fi
        if [ "$1" = '' ]; then
@@ -128,7 +147,7 @@ case "${1:-.}${2:-.}${3:-.}" in
        fi
 
        if [ $ret -ne 0 ]; then
-               echo "ERROR: Merge conflict in $4"
+               echo "ERROR: $msg in $4"
                exit 1
        fi
        exec git update-index -- "$4"