[ovs-dev] [PATCH v3] ovs-tcpdump: add dump_cmd checker before _doexec()

[txfh2007]

Hi Aaron:
    Thanks for your kinkdly suggession. I have tried your proposol and test in my repository. This is the new version.

    Add dump_cmd executable checker in ovs-tcpdump

    Signed-off-by: Liu Chang <txfh2007 at aliyun.com>

diff --git a/utilities/ovs-tcpdump.in b/utilities/ovs-tcpdump.in
index 269c252..911c608 100755
--- a/utilities/ovs-tcpdump.in
+++ b/utilities/ovs-tcpdump.in
@@ -371,6 +371,9 @@ def argv_tuples(lst):
     except StopIteration:
         pass

+def py_which(executable):
+        return any(os.access(os.path.join(path,executable),os.X_OK)
+                for path in os.environ["PATH"].split(os.pathsep))

 def main():
     db_sock = 'unix:@RUNDIR@/db.sock'
@@ -416,6 +419,10 @@ def main():
         print("Error: must at least specify an interface with '-i' option")
         sys.exit(1)

+    if not py_which(dump_cmd):
+        print("Error: unable to execute '%s' (check PATH)"%dump_cmd)
+        sys.exit(1)
+
     if '-l' not in tcpdargs:
         tcpdargs.insert(0, '-l')