decoders/ir_irmp/irmp_library.py

   1 ##
   2 ## This file is part of the libsigrokdecode project.
   3 ##
   4 ## Copyright (C) 2019 Rene Staffen
   5 ## Copyright (C) 2020-2021 Gerhard Sittig <gerhard.sittig@gmx.net>
   6 ##
   7 ## This program is free software; you can redistribute it and/or modify
   8 ## it under the terms of the GNU General Public License as published by
   9 ## the Free Software Foundation; either version 2 of the License, or
  10 ## (at your option) any later version.
  11 ##
  12 ## This program is distributed in the hope that it will be useful,
  13 ## but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 ## GNU General Public License for more details.
  16 ##
  17 ## You should have received a copy of the GNU General Public License
  18 ## along with this program; if not, see <http://www.gnu.org/licenses/>.
  19 ##
  20
  21 '''
  22 Python binding for the IRMP library.
  23 '''
  24
  25 import ctypes
  26 import platform
  27
  28 class IrmpLibrary:
  29     '''
  30     Library instance for an infrared protocol detector.
  31     '''
  32
  33     __usable_instance = None
  34
  35     class ResultData(ctypes.Structure):
  36         _fields_ = [
  37             ( 'protocol', ctypes.c_uint32, ),
  38             ( 'protocol_name', ctypes.c_char_p, ),
  39             ( 'address', ctypes.c_uint32, ),
  40             ( 'command', ctypes.c_uint32, ),
  41             ( 'flags', ctypes.c_uint32, ),
  42             ( 'start_sample', ctypes.c_uint32, ),
  43             ( 'end_sample', ctypes.c_uint32, ),
  44         ]
  45
  46     FLAG_REPETITION = 1 << 0
  47     FLAG_RELEASE = 1 << 1
  48
  49     def _library_filename(self):
  50         '''
  51         Determine the library filename depending on the platform.
  52         '''
  53
  54         if platform.uname()[0] == 'Linux':
  55             return 'libirmp.so'
  56         if platform.uname()[0] == 'Darwin':
  57             return 'libirmp.dylib'
  58         return 'irmp.dll'
  59
  60     def _library_setup_api(self):
  61         '''
  62         Lookup the C library's API routines. Declare their prototypes.
  63         '''
  64
  65         self._lib.irmp_get_sample_rate.restype = ctypes.c_uint32
  66         self._lib.irmp_get_sample_rate.argtypes = []
  67
  68         self._lib.irmp_instance_alloc.restype = ctypes.c_void_p
  69         self._lib.irmp_instance_alloc.argtypes = []
  70
  71         self._lib.irmp_instance_free.restype = None
  72         self._lib.irmp_instance_free.argtypes = [ ctypes.c_void_p, ]
  73
  74         self._lib.irmp_instance_id.restype = ctypes.c_size_t
  75         self._lib.irmp_instance_id.argtypes = [ ctypes.c_void_p, ]
  76
  77         self._lib.irmp_instance_lock.restype = ctypes.c_int
  78         self._lib.irmp_instance_lock.argtypes = [ ctypes.c_void_p, ctypes.c_int, ]
  79
  80         self._lib.irmp_instance_unlock.restype = None
  81         self._lib.irmp_instance_unlock.argtypes = [ ctypes.c_void_p, ]
  82
  83         self._lib.irmp_reset_state.restype = None
  84         self._lib.irmp_reset_state.argtypes = []
  85
  86         self._lib.irmp_add_one_sample.restype = ctypes.c_int
  87         self._lib.irmp_add_one_sample.argtypes = [ ctypes.c_int, ]
  88
  89         if False:
  90             self._lib.irmp_detect_buffer.restype = self.ResultData
  91             self._lib.irmp_detect_buffer.argtypes = [ ctypes.POINTER(ctypes.c_uint8), ctypes.c_size_t, ]
  92
  93         self._lib.irmp_get_result_data.restype = ctypes.c_int
  94         self._lib.irmp_get_result_data.argtypes = [ ctypes.POINTER(self.ResultData), ]
  95
  96         self._lib.irmp_get_protocol_name.restype = ctypes.c_char_p
  97         self._lib.irmp_get_protocol_name.argtypes = [ ctypes.c_uint32, ]
  98
  99         # Create a result buffer that's local to the library instance.
 100         self._data = self.ResultData()
 101         self._inst = None
 102
 103         return True
 104
 105     def __init__(self):
 106         '''
 107         Create a library instance.
 108         '''
 109
 110         filename = self._library_filename()
 111         self._lib = ctypes.cdll.LoadLibrary(filename)
 112         self._library_setup_api()
 113
 114     def __del__(self):
 115         '''
 116         Release a disposed library instance.
 117         '''
 118
 119         if self._inst:
 120             self._lib.irmp_instance_free(self._inst)
 121         self._inst = None
 122
 123     def __enter__(self):
 124         '''
 125         Enter a context (lock management).
 126         '''
 127
 128         if self._inst is None:
 129             self._inst = self._lib.irmp_instance_alloc()
 130         self._lib.irmp_instance_lock(self._inst, 1)
 131         return self
 132
 133     def __exit__(self, extype, exvalue, trace):
 134         '''
 135         Leave a context (lock management).
 136         '''
 137
 138         self._lib.irmp_instance_unlock(self._inst)
 139         return False
 140
 141     def client_id(self):
 142         return self._lib.irmp_instance_id(self._inst)
 143
 144     def get_sample_rate(self):
 145         return self._lib.irmp_get_sample_rate()
 146
 147     def reset_state(self):
 148         self._lib.irmp_reset_state()
 149
 150     def add_one_sample(self, level):
 151         if not self._lib.irmp_add_one_sample(int(level)):
 152             return False
 153         self._lib.irmp_get_result_data(ctypes.byref(self._data))
 154         return True
 155
 156     def get_result_data(self):
 157         if not self._data:
 158             return None
 159         return {
 160             'proto_nr': self._data.protocol,
 161             'proto_name': self._data.protocol_name.decode('UTF-8', 'ignore'),
 162             'address': self._data.address,
 163             'command': self._data.command,
 164             'repeat': bool(self._data.flags & self.FLAG_REPETITION),
 165             'release': bool(self._data.flags & self.FLAG_RELEASE),
 166             'start': self._data.start_sample,
 167             'end': self._data.end_sample,
 168         }