Override "p4 diff" to handle change numbers.

Wrapper around "p4 diff" which detects use of the -c flag and calls
p4-diffchange, thus enabling uses such as "p4 diff -c 12345" which will
show diffs only for files opened in changelist 12345.

diff --git a/opt/p4/p4-diff b/opt/p4/p4-diff
new file mode 100755 (executable)
index 0000000..2ecc0d5
--- /dev/null
+++ b/opt/p4/p4-diff
@@ -0,0 +1,17 @@
+#!/bin/bash
+
+. ${0%/*}/common
+
+function parse_change() {
+  while getopts ":c:" opt; do
+    case $opt in
+      c) echo $OPTARG;;
+    esac
+  done
+}
+
+if [ -n "$(parse_change $*)" ]; then
+  exec ${0%/*}/p4-diffchange $p4opts diffchange ${1+"$@"}
+else
+  exec p4 $p4opts $p4command ${1+"$@"}
+fi