scripts/tracetool/format/__init__.py

   1 # -*- coding: utf-8 -*-
   2
   3 """
   4 Format management.
   5
   6
   7 Creating new formats
   8 --------------------
   9
  10 A new format named 'foo-bar' corresponds to Python module
  11 'tracetool/format/foo_bar.py'.
  12
  13 A format module should provide a docstring, whose first non-empty line will be
  14 considered its short description.
  15
  16 All formats must generate their contents through the 'tracetool.out' routine.
  17
  18
  19 Format functions
  20 ----------------
  21
  22 ======== ==================================================================
  23 Function Description
  24 ======== ==================================================================
  25 generate Called to generate a format-specific file.
  26 ======== ==================================================================
  27
  28 """
  29
  30 __author__     = "Lluís Vilanova <vilanova@ac.upc.edu>"
  31 __copyright__  = "Copyright 2012-2014, Lluís Vilanova <vilanova@ac.upc.edu>"
  32 __license__    = "GPL version 2 or (at your option) any later version"
  33
  34 __maintainer__ = "Stefan Hajnoczi"
  35 __email__      = "stefanha@redhat.com"
  36
  37
  38 import os
  39
  40 import tracetool
  41
  42
  43 def get_list():
  44     """Get a list of (name, description) pairs."""
  45     res = []
  46     modnames = []
  47     for filename in os.listdir(tracetool.format.__path__[0]):
  48         if filename.endswith('.py') and filename != '__init__.py':
  49             modnames.append(filename.rsplit('.', 1)[0])
  50     for modname in sorted(modnames):
  51         module = tracetool.try_import("tracetool.format." + modname)
  52
  53         # just in case; should never fail unless non-module files are put there
  54         if not module[0]:
  55             continue
  56         module = module[1]
  57
  58         doc = module.__doc__
  59         if doc is None:
  60             doc = ""
  61         doc = doc.strip().split("\n")[0]
  62
  63         name = modname.replace("_", "-")
  64         res.append((name, doc))
  65     return res
  66
  67
  68 def exists(name):
  69     """Return whether the given format exists."""
  70     if len(name) == 0:
  71         return False
  72     name = name.replace("-", "_")
  73     return tracetool.try_import("tracetool.format." + name)[1]
  74
  75
  76 def generate(events, format, backend, group):
  77     if not exists(format):
  78         raise ValueError("unknown format: %s" % format)
  79     format = format.replace("-", "_")
  80     func = tracetool.try_import("tracetool.format." + format,
  81                                 "generate")[1]
  82     if func is None:
  83         raise AttributeError("format has no 'generate': %s" % format)
  84     func(events, backend, group)