info.py: add optional kmod modinfo section.

The older info.py version only used comedilib to extract board
information, including the comedi version in use.  While the
out-of-kernel comedi module does bump their versions (occasionally ;),
the in-kernel staging drivers still claim version 0.7.76 (despite
being mostly equivalent to the out-of-tree module 0.10.1).  This makes
it useful to differentiate between in-kernel and out-of-kernel modules
by printing some modinfo details, for which I'm using the kmod Python
bindings (python-kmod).

I'm currently using my Cython branch of python-kmod, which is pending
a merge upstream [1].

[1]: https://github.com/agrover/python-kmod/pull/3

diff --git a/doc/demo/info.py b/doc/demo/info.py
index e5c76e4452fb0079267b73eccac65238736c49b6..ce3f176e1a4266986adf7d4401a6b08052cdb9a7 100755 (executable)
--- a/doc/demo/info.py
+++ b/doc/demo/info.py
@@ -19,12 +19,39 @@
 """Gather and display information about a comedi device.
 """
 
+try:
+    import kmod as _kmod
+    import kmod.error as _kmod_error
+except ImportError as e:
+    _kmod = None
+    _kmod_import_error = e
+
 from pycomedi import PyComediError as _PyComediError
 import pycomedi.constant as _constant
 from pycomedi.device import Device as _Device
 from pycomedi.subdevice import StreamingSubdevice as _StreamingSubdevice
 
 
+class ModuleNotFound (ValueError):
+    pass
+
+
+def display_modinfo(module_name):
+    if _kmod is None:
+        raise _kmod_import_error
+    kmod = _kmod.Kmod()
+    mod = kmod.module_from_name(name=module_name)
+    items = [('filename', mod.path)]
+    try:
+        items.extend(mod.info.items())
+    except _kmod_error.KmodError as e:
+        raise ModuleNotFound(module_name)
+    longest_key = max(len(k) for k,v in items)
+    print('modinfo for {}'.format(module_name))
+    for k,v in items:
+        space = ' '*(longest_key + 4 - len(k))
+        print('  {}:{}{}'.format(k, space, v))
+
 def display_maxdata(subdevice):
     if subdevice.maxdata_is_chan_specific():
         print('  max data value: (channel specific)')
@@ -127,6 +154,14 @@ def run(filename):
       ranges: <Range unit:none min:0.0 max:1.0>
       command: (not supported)
     """
+    try:
+        display_modinfo('comedi')
+    except ImportError as e:
+        print('could not load module info (kmod not installed)')
+        print('  {}'.format(e))
+    except ModuleNotFound as e:
+        print('could not load module info (module not found)')
+        print('  {}'.format(e))
     device = _Device(filename=filename)
     device.open()
     try: