script:svn_patch: improve help and use revision

scripts/svn_patch

@@ -5,7 +5,14 @@ IFS=$'\n\t'
 addHeader=false
 
 function usage {
-	echo -e "Usage: $(basename $0) [NB_COMMIT]"
+	echo -e "Usage: $(basename $0) [OPTIONS] COMMIT"
+	echo -e "       Generate patch from COMMIT."
+	echo -e "       COMMIT is either:"
+        echo -e "               * a number of commit"
+        echo -e "               * a revision starting with r"
+	echo -e ""
+	echo -e "Available options:"
+        echo -e "       -h: add commit msg to the beginning of the patches"
 }
 
 while getopts ":h" opt; do
@@ -26,10 +33,15 @@ if [ $# != 1 ]; then
         usage
         exit 1
 fi
-
+revision=0
+if [[ $1 == r* ]];then
+        revisions=$(svn log -rHEAD:${1#r} | grep -e "^r[0-9]" | cut -f1 -d" " | cut -c2-)
+else
         nb_rev=$1
         nb_rev=$((nb_rev+1))
         revisions=$(svn log -l $nb_rev | grep -e "^r[0-9]" | cut -f1 -d" " | cut -c2-)
+fi
+
 i=0
 prev=0
 first=0