def display_log():
args = _parse_args()
if args['help']:
_display_help()
return
_display_header()
log = TrimmingLog('msglog')
start = 0
try:
if args['tail_lines'] is not None or args['follow']:
tail_lines = 10
if args['tail_lines'] != None:
tail_lines = int(args['tail_lines'])
assert tail_lines >= -1, (
"tail_lines must be greater than or eaual to -1")
if tail_lines == -1:
start = int(log.get_first_record()['_seq'])
else:
start = int(log.get_last_record()['_seq']) - tail_lines + 1
else:
start = int(log.get_first_record()['_seq'])
except AssertionError:
raise # Reraise the original exception.
except:
pass
end = args['head_lines']
assert end is None or end >= 0, (
"head_lines must be None or it must be greater than or eaual to 0")
entries = ()
try:
if end is not None:
end += start
entries = log[start:end]
else:
end = start
entries = log[start:]
end += len(entries)
except ENoData:
entries = []
pass
for entry in entries:
_display_message(entry, args['color'], args['match'])
if args['follow']:
# If the file doesn't exist, there doesn't seem to be an obvious
# way to gracefully recover at this point. Just inform the user
# that the file doesn't exist, and bail. While we are at it,
# we can make sure that the file does exist so that the next
# time we are run, we have half a chance.
if not os.path.exists(log.filename):
print 'Error: %s does not exist. Please restart.' % log.filename
try:
fd = open(log.filename, 'a+')
fd.close()
except:
pass
return
_initialize_stat(log.filename)
restart = end
while 1:
try:
entries = log[restart:]
restart += len(entries)
for entry in entries:
_display_message(entry, args['color'], args['match'])
except ENoData:
pass
# Sleep until either the file has changed, or
# a certain maximum amount of time has elasped.
_sleep_until_file_changes_with_timeout(log.filename,
max_wait_time)
