Merge pull request iovisor#134 from iovisor/bblanco_dev

Add format string argument to bpf-run

src/python/bpf-run

@@ -4,14 +4,15 @@ import sys
 
 USAGE = """\
 usage: {argv0} <opts> -p probe_func -c cmd
- -c cmd contents of the program to run, omitting prototype
+ -c cmd contents of the program to run, omitting prototype (required)
  -d name dump table <name> upon exit
+ -f format format string to apply to trace output (see python str.format())
  -n sec run for <sec> seconds and then exit (default=-1)
  -p probe kernel entry point to trace (required)
  -t attach to kernel trace output
  -v increase verbosity
 example:
- {argv0} -p sys_clone -c 'bpf_trace_printk("hello\\n");' -t\
+ {argv0} -p sys_clone -c 'bpf_trace_printk("Hello, World!\\n");' -t\
 """
 
 wrapper = """
@@ -35,7 +36,7 @@ def main():
  import signal
 
  try:
- opts, args = getopt.getopt(sys.argv[1:], "c:d:hn:p:tv")
+ opts, args = getopt.getopt(sys.argv[1:], "c:d:f:hn:p:tv")
  except getopt.error, msg:
  print_usage_and_exit(2, msg)
 
@@ -45,15 +46,17 @@ def main():
  dump_tables = []
  verbose = 0
  nsec = 0
+ format_str = None
 
  for o, a in opts:
+ if o == "-c": runcmd = a
  if o == "-d": dump_tables.append(a)
+ if o == "-f": format_str = a
+ if o == "-h": print_usage_and_exit(0)
  if o == "-n": nsec = int(a)
+ if o == "-p": probe_fn = a
  if o == "-t": trace = 1
  if o == "-v": verbose += 1
- if o == "-c": runcmd = a
- if o == "-p": probe_fn = a
- if o == "-h": print_usage_and_exit(0)
 
  if not runcmd or not probe_fn:
  print_usage_and_exit(2, "Error: -p and -c arguments are required")
@@ -75,7 +78,11 @@ def main():
  with open("/sys/kernel/debug/tracing/trace_pipe") as f:
  while True:
  line = f.readline(128)
- print(line.rstrip())
+ line = line.rstrip()
+ if format_str:
+ args=line.split(None, 5)
+ line = format_str.format(*args)
+ print(line)
  sys.stdout.flush()
  elif nsec:
  signal.pause()