-simplify to use new namestore API to skip initial iteration, document now passing...
[oweals/gnunet.git] / contrib / pydmesg
1 #!/usr/bin/env python
2 # coding=utf8
3
4 # Copyright (C) 2010 Saúl ibarra Corretgé <saghul@gmail.com>
5 #
6
7 """
8 pydmesg: dmesg with human-readable timestamps
9 """
10
11 from __future__ import with_statement
12
13 import re
14 import subprocess
15 import sys
16
17 from datetime import datetime, timedelta
18
19
20 _datetime_format = "%Y-%m-%d %H:%M:%S"
21 _dmesg_line_regex = re.compile("^\[(?P<time>\d+\.\d+)\](?P<line>.*)$")
22
23 def exec_process(cmdline, silent, input=None, **kwargs):
24     """Execute a subprocess and returns the returncode, stdout buffer and stderr buffer.
25        Optionally prints stdout and stderr while running."""
26     try:
27         sub = subprocess.Popen(cmdline, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE, **kwargs)
28         stdout, stderr = sub.communicate(input=input)
29         returncode = sub.returncode
30         if not silent:
31             sys.stdout.write(stdout)
32             sys.stderr.write(stderr)
33     except OSError,e:
34         if e.errno == 2:
35             raise RuntimeError('"%s" is not present on this system' % cmdline[0])
36         else:
37             raise
38     if returncode != 0:
39         raise RuntimeError('Got return value %d while executing "%s", stderr output was:\n%s' % (returncode, " ".join(cmdline), stderr.rstrip("\n")))
40     return stdout
41
42 def human_dmesg():
43     now = datetime.now()
44     uptime_diff = None
45     try:
46         with open('/proc/uptime') as f:
47             uptime_diff = f.read().strip().split()[0]
48     except IndexError:
49         return
50     else:
51         try:
52             uptime = now - timedelta(seconds=int(uptime_diff.split('.')[0]), microseconds=int(uptime_diff.split('.')[1]))
53         except IndexError:
54             return
55
56     dmesg_data = exec_process(['dmesg'], True)
57     for line in dmesg_data.split('\n'):
58         if not line:
59             continue
60         match = _dmesg_line_regex.match(line)
61         if match:
62             try:
63                 seconds = int(match.groupdict().get('time', '').split('.')[0])
64                 nanoseconds = int(match.groupdict().get('time', '').split('.')[1])
65                 microseconds = int(round(nanoseconds * 0.001))
66                 line = match.groupdict().get('line', '')
67                 t = uptime + timedelta(seconds=seconds, microseconds=microseconds)
68             except IndexError:
69                 pass
70             else:
71                 print "[%s]%s" % (t.strftime(_datetime_format), line)
72
73
74 if __name__ == '__main__':
75     human_dmesg()