1 files changed, 159 insertions, 0 deletions
diff --git a/devtools/check-symbol-change.sh b/devtools/check-symbol-change.sh
new file mode 100755
index 00000000..daaf45e1
--- /dev/null
+++ b/devtools/check-symbol-change.sh
@@ -0,0 +1,159 @@
+#!/bin/sh
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright(c) 2018 Neil Horman <nhorman@tuxdriver.com>
+
+build_map_changes()
+{
+	local fname="$1"
+	local mapdb="$2"
+
+	cat "$fname" | awk '
+		# Initialize our variables
+		BEGIN {map="";sym="";ar="";sec=""; in_sec=0; in_map=0}
+
+		# Anything that starts with + or -, followed by an a
+		# and ends in the string .map is the name of our map file
+		# This may appear multiple times in a patch if multiple
+		# map files are altered, and all section/symbol names
+		# appearing between a triggering of this rule and the
+		# next trigger of this rule are associated with this file
+		/[-+] a\/.*\.map/ {map=$2; in_map=1}
+
+		# Same pattern as above, only it matches on anything that
+		# does not end in 'map', indicating we have left the map chunk.
+		# When we hit this, turn off the in_map variable, which
+		# supresses the subordonate rules below
+		/[-+] a\/.*\.^(map)/ {in_map=0}
+
+		# Triggering this rule, which starts a line with a + and ends it
+		# with a { identifies a versioned section.  The section name is
+		# the rest of the line with the + and { symbols remvoed.
+		# Triggering this rule sets in_sec to 1, which actives the
+		# symbol rule below
+		/+.*{/ {gsub("+","");
+			if (in_map == 1) {
+				sec=$1; in_sec=1;
+			}
+		}
+
+		# This rule idenfies the end of a section, and disables the
+		# symbol rule
+		/.*}/ {in_sec=0}
+
+		# This rule matches on a + followed by any characters except a :
+		# (which denotes a global vs local segment), and ends with a ;.
+		# The semicolon is removed and the symbol is printed with its
+		# association file name and version section, along with an
+		# indicator that the symbol is a new addition.  Note this rule
+		# only works if we have found a version section in the rule
+		# above (hence the in_sec check) And found a map file (the
+		# in_map check).  If we are not in a map chunk, do nothing.  If
+		# we are in a map chunk but not a section chunk, record it as
+		# unknown.
+		/^+[^}].*[^:*];/ {gsub(";","");sym=$2;
+			if (in_map == 1) {
+				if (in_sec == 1) {
+					print map " " sym " " sec " add"
+				} else {
+					print map " " sym " unknown add"
+				}
+			}
+		}
+
+		# This is the same rule as above, but the rule matches on a
+		# leading - rather than a +, denoting that the symbol is being
+		# removed.
+		/^-[^}].*[^:*];/ {gsub(";","");sym=$2;
+			if (in_map == 1) {
+				if (in_sec == 1) {
+					print map " " sym " " sec " del"
+				} else {
+					print map " " sym " unknown del"
+				}
+			}
+		}' > "$mapdb"
+
+		sort -u "$mapdb" > "$mapdb.2"
+		mv -f "$mapdb.2" "$mapdb"
+
+}
+
+check_for_rule_violations()
+{
+	local mapdb="$1"
+	local mname
+	local symname
+	local secname
+	local ar
+	local ret=0
+
+	while read mname symname secname ar
+	do
+		if [ "$ar" = "add" ]
+		then
+
+			if [ "$secname" = "unknown" ]
+			then
+				# Just inform the user of this occurrence, but
+				# don't flag it as an error
+				echo -n "INFO: symbol $syname is added but "
+				echo -n "patch has insuficient context "
+				echo -n "to determine the section name "
+				echo -n "please ensure the version is "
+				echo "EXPERIMENTAL"
+				continue
+			fi
+
+			if [ "$secname" != "EXPERIMENTAL" ]
+			then
+				# Symbols that are getting added in a section
+				# other than the experimental section
+				# to be moving from an already supported
+				# section or its a violation
+				grep -q \
+				"$mname $symname [^EXPERIMENTAL] del" "$mapdb"
+				if [ $? -ne 0 ]
+				then
+					echo -n "ERROR: symbol $symname "
+					echo -n "is added in a section "
+					echo -n "other than the EXPERIMENTAL "
+					echo "section of the version map"
+					ret=1
+				fi
+			fi
+		else
+
+			if [ "$secname" != "EXPERIMENTAL" ]
+			then
+				# Just inform users that non-experimenal
+				# symbols need to go through a deprecation
+				# process
+				echo -n "INFO: symbol $symname is being "
+				echo -n "removed, ensure that it has "
+				echo "gone through the deprecation process"
+			fi
+		fi
+	done < "$mapdb"
+
+	return $ret
+}
+
+trap clean_and_exit_on_sig EXIT
+
+mapfile=`mktemp mapdb.XXXXXX`
+patch=$1
+exit_code=1
+
+clean_and_exit_on_sig()
+{
+	rm -f "$mapfile"
+	exit $exit_code
+}
+
+build_map_changes "$patch" "$mapfile"
+check_for_rule_violations "$mapfile"
+exit_code=$?
+
+rm -f "$mapfile"
+
+exit $exit_code