guilt: improve the generation of an automatic header

Patches that do not have a proper header are encountered when generating
a tree. This improves the detection of these patches and generates a sane
header so the eventual commit will be coherent

Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com>

---

 guilt |   24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

--- a/guilt
+++ b/guilt
@@ -591,7 +591,12 @@ commit()
 		fi
 
 		# last try: make a default commit message if patch doesn't contain one
-		[ ! -s "$TMP_MSG" ] && echo "auto_msg: patch $pname" > "$TMP_MSG"
+		if [ ! -s "$TMP_MSG" ]; then
+		    echo "auto_msg: importing `basename $pname`" > "$TMP_MSG"
+		    echo "" >> "$TMP_MSG"
+		    echo "This is an automatic import of patch $pname, no headers were" >> "$TMP_MSG"
+		    echo "detected and a default message was constructed" >>  "$TMP_MSG"
+		fi
 
 
 		if [ "$header_type" = "guilt" ]; then
@@ -599,12 +604,14 @@ commit()
   		    # extract a From line from the patch header, and set
 	            # GIT_AUTHOR_{NAME,EMAIL}
 		    author_str=`sed -n -e '/^From:/ { s/^From: //; p; q }; /^(diff |---)/ q' "$p"`
-		    if [ ! -z "$author_str" ]; then
-			GIT_AUTHOR_NAME=`echo $author_str | sed -e 's/ *<.*$//'`
-			export GIT_AUTHOR_NAME="${GIT_AUTHOR_NAME:-" "}"
-                        export GIT_AUTHOR_EMAIL="`echo $author_str | sed -e 's/[^<]*//'`"
+		    if [ -z "$author_str" ]; then
+			author_str="auto commit <unknown@unknown>"
 		    fi
 
+		    GIT_AUTHOR_NAME=`echo $author_str | sed -e 's/ *<.*$//'`
+		    export GIT_AUTHOR_NAME="${GIT_AUTHOR_NAME:-" "}"
+                    export GIT_AUTHOR_EMAIL="`echo $author_str | sed -e 's/[^<]*//'`"
+
 
 		    # check in the patch for a subject
 		    SUBJECT="$(sed -n '/^Subject/ s/Subject: //p' "$p")"
@@ -615,6 +622,11 @@ commit()
 			if [ ${#SUBJECT} -gt 60 ]; then
 			    SUBJECT=${SUBJECT: -60}
 			fi
+
+			# remove the line from the tmp msg
+			mv "$TMP_MSG" "$TMP_MSG.work"
+			cat "$TMP_MSG.work" | grep -v -E ".*$SUBJECT.*" > "$TMP_MSG"
+			rm "$TMP_MSG.work"
 		    fi
 
 		    if [ -z "$SUBJECT" ]; then
@@ -629,7 +641,7 @@ commit()
 
 		    SUBJECT=`echo $SUBJECT | sed s'%^ *%%'`
 
-		    if [ ! -z "$SUBJECT" ]; then
+		    if [ -n "$SUBJECT" ]; then
 			echo "$SUBJECT" >> $TMP_MSG.subject
 			echo "" >> $TMP_MSG.subject
 			cat "$TMP_MSG" >> $TMP_MSG.subject