add scripts for generating a diff from p4...

awkdiff is the script from scottl that he got from ken a long time
ago...  It no longer lives in his home dir, so give it a new home...
This does simple massaging of p4 output to create a useful diff...

The script p4diffbranch will create a diff that includes new and
deleted files unlike the normal diff2 -b command...  So will be useful
for extracting patches from p4...  It does take a changeset that will
be used to diff against...

tools/tools/perforce/awkdiff

@@ -0,0 +1,42 @@
+#!/usr/bin/awk -f
+#
+#	$FreeBSD$
+#
+
+BEGIN {
+	#parentpath = "//depot/vendor/freebsd/src/sys/"
+	#childpath = "//depot/projects/opencrypto/"
+}
+$1 == "====" {
+	last_line = $0
+	last_filename = $2
+	#gsub(parentpath, "", last_filename)
+	gsub(/#[0-9]*$/, "", last_filename)
+	did_sub = 0
+}
+$1 == "====" && $2 == "<none>" {
+	new_file = $4
+	gsub(childpath, "", new_file)
+	gsub(/#[0-9]*$/, "", new_file)
+	cmd = "p4 print \"" $4 "\" | sed '/^\\/\\/depot/d' | diff -u /dev/null /dev/stdin | sed s@/dev/stdin@" new_file "@"
+	#print "x" cmd "x"
+	system(cmd)
+}
+$1 == "====" && $4 == "<none>" {
+	del_file = $2
+	gsub(parentpath, "", del_file)
+	gsub(/#[0-9]*$/, "", del_file)
+	cmd = "p4 print \"" $2 "\" | sed '/^\\/\\/depot/d' | diff -u /dev/stdin /dev/null | sed s@/dev/stdin@" del_file "@"
+	#print "x" cmd "x"
+	system(cmd)
+}
+$1 != "====" {
+	if (!did_sub && (($1 == "***************") || ($1 == "@@"))) {
+		print "--- ", last_filename ".orig"
+		print "+++ ", last_filename
+		print $0
+		did_sub = 1
+	} else {
+		print $0
+	}
+}

tools/tools/perforce/p4diffbranch

@@ -0,0 +1,19 @@
+#!/bin/sh -
+#
+#	$FreeBSD$
+#
+
+if [ x"$#" != x"2" ]; then
+	echo "Usage: $0 <branch> <changesetnum>"
+	exit 1
+fi
+
+basescript="$(realpath "$0")"
+awkdiff="${basescript%/*}/awkdiff"
+
+branch="$1"
+changenum="$2"
+
+p4 branch -o "$branch" |
+	awk ' /^View:/ { doview = 1; next; } /^[^	]/ {doview = 0; next; } $1 && $2 && doview == 1 { system("p4 diff2 -du " $1 "@" changenum " " $2) }' changenum="$changenum" |
+	"$awkdiff"