[PATCH v5 11/11] devtools: prevent new instances of rte_panic and rte_exit

[Arnon Warshavsky <arnon@qwilt.com>]

This patch adds a new function that is called
per every checked patch,
and alerts for new instances of rte_panic/rte_exit.
The check excludes comments, and alerts in the case
of a positive balance between additions and removals.

Signed-off-by: Arnon Warshavsky <arnon@qwilt.com>
---
 devtools/checkpatches.sh | 95 +++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 94 insertions(+), 1 deletion(-)

diff --git a/devtools/checkpatches.sh b/devtools/checkpatches.sh
index 7676a6b..48b2685 100755
--- a/devtools/checkpatches.sh
+++ b/devtools/checkpatches.sh
@@ -61,6 +61,91 @@ print_usage () {
 	END_OF_HELP
 }
 
+check_forbidden_additions() { # <file>
+    # ---------------------------------
+    #This awk script receives a list of expressions to monitor
+    #and a list of folders to search these expressions in
+    # - No search is done inside comments
+    # - Both additions and removals of the expressions are checked
+    #   A positive balance of additions fails the check
+	read -d '' awk_script << 'EOF'
+	BEGIN{
+		split(FOLDERS,deny_folders," ");
+		split(EXPRESSIONS,deny_expr," ");
+		in_file=0;
+		in_comment=0;
+		count=0;
+		comment_start="/*"
+		comment_end="*/"
+    }
+    # search for add/remove instances in current file
+    # state machine assumes the comments structure is enforced by
+    # checkpatches.pl
+    (in_file) {
+		# comment start
+		if (index($0,comment_start) > 0){
+			in_comment = 1
+		}
+		# non comment code
+		if (in_comment == 0) {
+			for (i in deny_expr) {
+				forbidden_added = "^\+.*" deny_expr[i];
+				forbidden_removed="^-.*" deny_expr[i];
+				current = expressions[deny_expr[i]]
+				if ($0 ~ forbidden_added) {
+					count = count + 1;
+					expressions[deny_expr[i]] = current + 1
+				}
+				if ($0 ~ forbidden_removed) {
+					count = count - 1;
+					expressions[deny_expr[i]] = current - 1
+				}
+			}
+		}
+
+		# comment end
+		if (index($0,comment_end) > 0)  {
+			in_comment = 0
+		}
+    }
+	# switch to next file , check if the balance of add/remove
+	# of previous filehad new additions
+	($0 ~ "^\+\+\+ b/") {
+		in_file = 0;
+		if (count > 0){
+			exit;
+		}
+		for (i in deny_folders){
+			re = "^\+\+\+ b/" deny_folders[i];
+			if ($0 ~ deny_folders[i]) {
+				in_file = 1
+				last_file = $0
+			}
+		}
+	}
+	END{
+		if (count > 0){
+			print "Warning: in " substr(last_file,6) ":"
+			print "are you sure you want to add the following:"
+			for (key in expressions) {
+				if (expressions[key] > 0) {
+					print key
+				}
+			}
+			exit 1
+		}
+	}
+EOF
+	# ---------------------------------
+
+	# refrain from new additions of rte_panic() and rte_exit()
+	# under lib and net
+	# multiple folders and expressions are separated by spaces
+	awk -v FOLDERS="lib net" \
+		-v EXPRESSIONS="rte_panic\\\( rte_exit\\\(" \
+		"$awk_script" -
+}
+
 number=0
 quiet=false
 verbose=false
@@ -89,11 +174,19 @@ check () { # <patch> <commit> <title>
 	total=$(($total + 1))
 	! $verbose || printf '\n### %s\n\n' "$3"
 	if [ -n "$1" ] ; then
+		cat "$1" | check_forbidden_additions
+		[ $? -eq 0 ] || return 0
 		report=$($DPDK_CHECKPATCH_PATH $options "$1" 2>/dev/null)
 	elif [ -n "$2" ] ; then
-		report=$(git format-patch --find-renames --no-stat --stdout -1 $commit |
+		params=$(echo "--find-renames --no-stat --stdout -1")
+		body=$(git format-patch $params $commit)
+		echo "$body" | check_forbidden_additions
+		[ $? -eq 0 ] || return 0
+		report=$(echo "$body" |
 			$DPDK_CHECKPATCH_PATH $options - 2>/dev/null)
 	else
+		check_forbidden_additions -
+		[ $? -eq 0 ] || return 0
 		report=$($DPDK_CHECKPATCH_PATH $options - 2>/dev/null)
 	fi
 	[ $? -ne 0 ] || return 0
-- 
1.8.3.1