]> sigrok.org Git - libsigrok.git/commitdiff
python: Add high level API.
authorMartin Ling <redacted>
Wed, 17 Apr 2013 13:30:31 +0000 (14:30 +0100)
committerMartin Ling <redacted>
Wed, 17 Apr 2013 13:30:31 +0000 (14:30 +0100)
bindings/python/sigrok/core/__init__.py
bindings/python/sigrok/core/classes.py [new file with mode: 0644]

index 9b280ff6fba5886c1cc5436e08bc6df087d82e39..4c1f4319f3e88c90d7a24e9f6509b4f8b61431e3 100644 (file)
@@ -1 +1,3 @@
 import lowlevel
+import classes
+from classes import *
diff --git a/bindings/python/sigrok/core/classes.py b/bindings/python/sigrok/core/classes.py
new file mode 100644 (file)
index 0000000..cf955e9
--- /dev/null
@@ -0,0 +1,250 @@
+##
+## This file is part of the sigrok project.
+##
+## Copyright (C) 2013 Martin Ling <martin-sigrok@earth.li>
+##
+## This program is free software: you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation, either version 3 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program.  If not, see <http://www.gnu.org/licenses/>.
+##
+
+from functools import partial
+from fractions import Fraction
+from lowlevel import *
+import lowlevel
+import itertools
+
+__all__ = ['Error', 'Context', 'Driver', 'Device', 'Session', 'Packet']
+
+class Error(Exception):
+
+    def __str__(self):
+        return sr_strerror(self.args[0])
+
+def check(result):
+    if result != SR_OK:
+        raise Error(result)
+
+def config_key(name):
+    if not name.lower() == name:
+        raise AttributeError
+    key_name = "SR_CONF_" + name.upper()
+    return getattr(lowlevel, key_name)
+
+def gvariant_to_python(value):
+    type_string = g_variant_get_type_string(value)
+    if type_string == 't':
+        return g_variant_get_uint64(value)
+    if type_string == 'b':
+        return g_variant_get_bool(value)
+    if type_string == 'd':
+        return g_variant_get_double(value)
+    if type_string == 's':
+        return g_variant_get_string(value, None)
+    if type_string == '(tt)':
+        return Fraction(
+            g_variant_get_uint64(g_variant_get_child_value(value, 0)),
+            g_variant_get_uint64(g_variant_get_child_value(value, 1)))
+    raise NotImplementedError, (
+        "Can't convert GVariant type '%s' to a Python type." % type_string)
+
+def python_to_gvariant(value):
+    if isinstance(value, int):
+        return g_variant_new_uint64(value)
+    if isinstance(value, bool):
+        return g_variant_new_boolean(value)
+    if isinstance(value, float):
+        return g_variant_new_double(value)
+    if isinstance(value, str):
+        return g_variant_new_string(value)
+    if isinstance(value, Fraction):
+        array = new_gvariant_ptr_array(2)
+        gvariant_ptr_array_setitem(array, 0, value.numerator)
+        gvariant_ptr_array_setitem(array, 1, value.denominator)
+        result = g_variant_new_tuple(array, 2)
+        delete_gvariant_ptr_array(array)
+        return result
+    raise NotImplementedError, (
+        "Can't convert Python '%s' to a GVariant." % type(value))
+
+def callback_wrapper(session, callback, device_ptr, packet_ptr):
+    device = session.context._devices[int(device_ptr.this)]
+    packet = Packet(session, packet_ptr)
+    callback(device, packet)
+
+class Context(object):
+
+    def __init__(self):
+        context_ptr_ptr = new_sr_context_ptr_ptr()
+        check(sr_init(context_ptr_ptr))
+        self.struct = sr_context_ptr_ptr_value(context_ptr_ptr)
+        self._drivers = None
+        self._devices = {}
+        self.session = None
+
+    def __del__(self):
+        sr_exit(self.struct)
+
+    @property
+    def drivers(self):
+        if not self._drivers:
+            self._drivers = {}
+            driver_list = sr_driver_list()
+            for i in itertools.count():
+                driver_ptr = sr_dev_driver_ptr_array_getitem(driver_list, i)
+                if driver_ptr:
+                    self._drivers[driver_ptr.name] = Driver(self, driver_ptr)
+                else:
+                    break
+        return self._drivers
+
+class Driver(object):
+
+    def __init__(self, context, struct):
+        self.context = context
+        self.struct = struct
+        self._initialized = False
+
+    @property
+    def name(self):
+        return self.struct.name
+
+    def scan(self):
+        if not self._initialized:
+            check(sr_driver_init(self.context.struct, self.struct))
+            self._initialized = True
+        devices = []
+        device_list = sr_driver_scan(self.struct, None)
+        device_list_item = device_list
+        while device_list_item:
+            ptr = device_list_item.data
+            device_ptr = gpointer_to_sr_dev_inst_ptr(ptr)
+            devices.append(Device(self, device_ptr))
+            device_list_item = device_list_item.next
+        g_slist_free(device_list)
+        return devices
+
+class Device(object):
+
+    def __new__(cls, driver, struct):
+        address = int(struct.this)
+        if address not in driver.context._devices:
+            device = super(Device, cls).__new__(cls, driver, struct)
+            driver.context._devices[address] = device
+        return driver.context._devices[address]
+
+    def __init__(self, driver, struct):
+        self.driver = driver
+        self.struct = struct
+
+    def __getattr__(self, name):
+        key = config_key(name)
+        data = new_gvariant_ptr_ptr()
+        try:
+            check(sr_config_get(self.driver.struct, key, data, self.struct))
+        except Error as error:
+            if error.errno == SR_ERR_ARG:
+                raise NotImplementedError, (
+                    "Device does not implement %s" % name)
+            else:
+                raise AttributeError
+        value = gvariant_ptr_ptr_value(data)
+        return gvariant_to_python(value)
+
+    def __setattr__(self, name, value):
+        try:
+            key = config_key(name)
+        except AttributeError:
+            super(Device, self).__setattr__(name, value)
+            return
+        check(sr_config_set(self.struct, key, python_to_gvariant(value)))
+
+    @property
+    def vendor(self):
+        return self.struct.vendor
+
+    @property
+    def model(self):
+        return self.struct.model
+
+    @property
+    def version(self):
+        return self.struct.version
+
+class Session(object):
+
+    def __init__(self, context):
+        assert context.session is None
+        self.context = context
+        self.struct = sr_session_new()
+        context.session = self
+
+    def __del__(self):
+        check(sr_session_destroy())
+
+    def add_device(self, device):
+        check(sr_session_dev_add(device.struct))
+
+    def add_callback(self, callback):
+        wrapper = partial(callback_wrapper, self, callback)
+        check(sr_session_datafeed_python_callback_add(wrapper))
+
+    def start(self):
+        check(sr_session_start())
+
+    def run(self):
+        check(sr_session_run())
+
+    def stop(self):
+        check(sr_session_stop())
+
+class Packet(object):
+
+    def __init__(self, session, struct):
+        self.session = session
+        self.struct = struct
+        self._payload = None
+
+    @property
+    def type(self):
+        return self.struct.type
+
+    @property
+    def payload(self):
+        if self._payload is None:
+            pointer = self.struct.payload
+            if self.struct.type == SR_DF_LOGIC:
+                self._payload = Logic(self,
+                    void_ptr_to_sr_datafeed_logic_ptr(pointer))
+            else:
+                raise NotImplementedError, (
+                    "No Python mapping for packet type %ѕ" % self.struct.type)
+        return self._payload
+
+class Logic(object):
+
+    def __init__(self, packet, struct):
+        self.packet = packet
+        self.struct = struct
+        self._data = None
+
+    @property
+    def data(self):
+        if self._data is None:
+            self._data = cdata(self.struct.data, self.struct.length)
+        return self._data
+
+for symbol_name in dir(lowlevel):
+    prefix = 'SR_DF_'
+    if symbol_name.startswith(prefix):
+        name = symbol_name[len(prefix):]
+        setattr(Packet, name, getattr(lowlevel, symbol_name))