Martin Woolley / microbit-dal

Solution for Bluetooth SIG hands-on training course

Dependencies:   BLE_API mbed-dev-bin nRF51822-bluetooth-mdw

Dependents:   microbit

Fork of microbit-dal-bluetooth-mdw_starter by Martin Woolley

source/drivers/MicroBitRadioEvent.cpp@22:23d7b9a4b082, 2016-07-13 (annotated)

Committer:
LancasterUniversity
Date:
Wed Jul 13 12:17:54 2016 +0100
Revision:
22:23d7b9a4b082
Parent:
1:8aa5cdb4ab67 
Synchronized with git rev 7cf98c22

Author: James Devine

microbit-dal: patch for fiber_wake_on_event



fiber_wake_on_event used to crash after forking a FOB fiber.



It would attempt to obtain a new fiber context, and would place it on the wait queue.

Then when that fiber was paged in, the context of that fiber would not have been

initialised, as the function presumed schedule would be called immediately after

fiber initialisation.



This patch catches that edge case.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Jonathan Austin 1:8aa5cdb4ab67 1 /*
Jonathan Austin 1:8aa5cdb4ab67 2 The MIT License (MIT)
Jonathan Austin 1:8aa5cdb4ab67 3
Jonathan Austin 1:8aa5cdb4ab67 4 Copyright (c) 2016 British Broadcasting Corporation.
Jonathan Austin 1:8aa5cdb4ab67 5 This software is provided by Lancaster University by arrangement with the BBC.
Jonathan Austin 1:8aa5cdb4ab67 6
Jonathan Austin 1:8aa5cdb4ab67 7 Permission is hereby granted, free of charge, to any person obtaining a
Jonathan Austin 1:8aa5cdb4ab67 8 copy of this software and associated documentation files (the "Software"),
Jonathan Austin 1:8aa5cdb4ab67 9 to deal in the Software without restriction, including without limitation
Jonathan Austin 1:8aa5cdb4ab67 10 the rights to use, copy, modify, merge, publish, distribute, sublicense,
Jonathan Austin 1:8aa5cdb4ab67 11 and/or sell copies of the Software, and to permit persons to whom the
Jonathan Austin 1:8aa5cdb4ab67 12 Software is furnished to do so, subject to the following conditions:
Jonathan Austin 1:8aa5cdb4ab67 13
Jonathan Austin 1:8aa5cdb4ab67 14 The above copyright notice and this permission notice shall be included in
Jonathan Austin 1:8aa5cdb4ab67 15 all copies or substantial portions of the Software.
Jonathan Austin 1:8aa5cdb4ab67 16
Jonathan Austin 1:8aa5cdb4ab67 17 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
Jonathan Austin 1:8aa5cdb4ab67 18 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
Jonathan Austin 1:8aa5cdb4ab67 19 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
Jonathan Austin 1:8aa5cdb4ab67 20 THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
Jonathan Austin 1:8aa5cdb4ab67 21 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
Jonathan Austin 1:8aa5cdb4ab67 22 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
Jonathan Austin 1:8aa5cdb4ab67 23 DEALINGS IN THE SOFTWARE.
Jonathan Austin 1:8aa5cdb4ab67 24 */
Jonathan Austin 1:8aa5cdb4ab67 25
Jonathan Austin 1:8aa5cdb4ab67 26 #include "MicroBitConfig.h"
Jonathan Austin 1:8aa5cdb4ab67 27 #include "MicroBitRadio.h"
Jonathan Austin 1:8aa5cdb4ab67 28
Jonathan Austin 1:8aa5cdb4ab67 29 /**
Jonathan Austin 1:8aa5cdb4ab67 30 * Provides a simple broadcast radio abstraction, built upon the raw nrf51822 RADIO module.
Jonathan Austin 1:8aa5cdb4ab67 31 *
Jonathan Austin 1:8aa5cdb4ab67 32 * This class provides the ability to extend the micro:bit's default EventModel to other micro:bits in the vicinity,
Jonathan Austin 1:8aa5cdb4ab67 33 * in a very similar way to the MicroBitEventService for BLE interfaces.
Jonathan Austin 1:8aa5cdb4ab67 34 *
Jonathan Austin 1:8aa5cdb4ab67 35 * It is envisaged that this would provide the basis for children to experiment with building their own, simple,
Jonathan Austin 1:8aa5cdb4ab67 36 * custom asynchronous events and actions.
Jonathan Austin 1:8aa5cdb4ab67 37 *
Jonathan Austin 1:8aa5cdb4ab67 38 * @note This API does not contain any form of encryption, authentication or authorisation. Its purpose is solely for use as a
Jonathan Austin 1:8aa5cdb4ab67 39 * teaching aid to demonstrate how simple communications operates, and to provide a sandpit through which learning can take place.
Jonathan Austin 1:8aa5cdb4ab67 40 * For serious applications, BLE should be considered a substantially more secure alternative.
Jonathan Austin 1:8aa5cdb4ab67 41 */
Jonathan Austin 1:8aa5cdb4ab67 42
Jonathan Austin 1:8aa5cdb4ab67 43 /**
Jonathan Austin 1:8aa5cdb4ab67 44 * Constructor.
Jonathan Austin 1:8aa5cdb4ab67 45 *
Jonathan Austin 1:8aa5cdb4ab67 46 * Creates an instance of MicroBitRadioEvent which offers the ability to extend
Jonathan Austin 1:8aa5cdb4ab67 47 * the micro:bit's default EventModel to other micro:bits in the vicinity.
Jonathan Austin 1:8aa5cdb4ab67 48 *
Jonathan Austin 1:8aa5cdb4ab67 49 * @param r The underlying radio module used to send and receive data.
Jonathan Austin 1:8aa5cdb4ab67 50 */
Jonathan Austin 1:8aa5cdb4ab67 51 MicroBitRadioEvent::MicroBitRadioEvent(MicroBitRadio &r) : radio(r)
Jonathan Austin 1:8aa5cdb4ab67 52 {
Jonathan Austin 1:8aa5cdb4ab67 53 this->suppressForwarding = false;
Jonathan Austin 1:8aa5cdb4ab67 54 }
Jonathan Austin 1:8aa5cdb4ab67 55
Jonathan Austin 1:8aa5cdb4ab67 56 /**
Jonathan Austin 1:8aa5cdb4ab67 57 * Associates the given event with the radio channel.
Jonathan Austin 1:8aa5cdb4ab67 58 *
Jonathan Austin 1:8aa5cdb4ab67 59 * Once registered, all events matching the given registration sent to this micro:bit's
Jonathan Austin 1:8aa5cdb4ab67 60 * default EventModel will be automatically retransmitted on the radio.
Jonathan Austin 1:8aa5cdb4ab67 61 *
Jonathan Austin 1:8aa5cdb4ab67 62 * @param id The id of the event to register.
Jonathan Austin 1:8aa5cdb4ab67 63 *
Jonathan Austin 1:8aa5cdb4ab67 64 * @param value the value of the event to register.
Jonathan Austin 1:8aa5cdb4ab67 65 *
Jonathan Austin 1:8aa5cdb4ab67 66 * @return MICROBIT_OK on success, or MICROBIT_NO_RESOURCES if no default EventModel is available.
Jonathan Austin 1:8aa5cdb4ab67 67 *
Jonathan Austin 1:8aa5cdb4ab67 68 * @note The wildcards MICROBIT_ID_ANY and MICROBIT_EVT_ANY can also be in place of the
Jonathan Austin 1:8aa5cdb4ab67 69 * id and value fields.
Jonathan Austin 1:8aa5cdb4ab67 70 */
Jonathan Austin 1:8aa5cdb4ab67 71 int MicroBitRadioEvent::listen(uint16_t id, uint16_t value)
Jonathan Austin 1:8aa5cdb4ab67 72 {
Jonathan Austin 1:8aa5cdb4ab67 73 if (EventModel::defaultEventBus)
Jonathan Austin 1:8aa5cdb4ab67 74 return listen(id, value, *EventModel::defaultEventBus);
Jonathan Austin 1:8aa5cdb4ab67 75
Jonathan Austin 1:8aa5cdb4ab67 76 return MICROBIT_NO_RESOURCES;
Jonathan Austin 1:8aa5cdb4ab67 77 }
Jonathan Austin 1:8aa5cdb4ab67 78
Jonathan Austin 1:8aa5cdb4ab67 79 /**
Jonathan Austin 1:8aa5cdb4ab67 80 * Associates the given event with the radio channel.
Jonathan Austin 1:8aa5cdb4ab67 81 *
Jonathan Austin 1:8aa5cdb4ab67 82 * Once registered, all events matching the given registration sent to the given
Jonathan Austin 1:8aa5cdb4ab67 83 * EventModel will be automatically retransmitted on the radio.
Jonathan Austin 1:8aa5cdb4ab67 84 *
Jonathan Austin 1:8aa5cdb4ab67 85 * @param id The id of the events to register.
Jonathan Austin 1:8aa5cdb4ab67 86 *
Jonathan Austin 1:8aa5cdb4ab67 87 * @param value the value of the event to register.
Jonathan Austin 1:8aa5cdb4ab67 88 *
Jonathan Austin 1:8aa5cdb4ab67 89 * @param eventBus The EventModel to listen for events on.
Jonathan Austin 1:8aa5cdb4ab67 90 *
Jonathan Austin 1:8aa5cdb4ab67 91 * @return MICROBIT_OK on success.
Jonathan Austin 1:8aa5cdb4ab67 92 *
Jonathan Austin 1:8aa5cdb4ab67 93 * @note The wildcards MICROBIT_ID_ANY and MICROBIT_EVT_ANY can also be in place of the
Jonathan Austin 1:8aa5cdb4ab67 94 * id and value fields.
Jonathan Austin 1:8aa5cdb4ab67 95 */
Jonathan Austin 1:8aa5cdb4ab67 96 int MicroBitRadioEvent::listen(uint16_t id, uint16_t value, EventModel &eventBus)
Jonathan Austin 1:8aa5cdb4ab67 97 {
Jonathan Austin 1:8aa5cdb4ab67 98 return eventBus.listen(id, value, this, &MicroBitRadioEvent::eventReceived, MESSAGE_BUS_LISTENER_IMMEDIATE);
Jonathan Austin 1:8aa5cdb4ab67 99 }
Jonathan Austin 1:8aa5cdb4ab67 100
Jonathan Austin 1:8aa5cdb4ab67 101 /**
Jonathan Austin 1:8aa5cdb4ab67 102 * Disassociates the given event with the radio channel.
Jonathan Austin 1:8aa5cdb4ab67 103 *
Jonathan Austin 1:8aa5cdb4ab67 104 * @param id The id of the events to deregister.
Jonathan Austin 1:8aa5cdb4ab67 105 *
Jonathan Austin 1:8aa5cdb4ab67 106 * @param value The value of the event to deregister.
Jonathan Austin 1:8aa5cdb4ab67 107 *
Jonathan Austin 1:8aa5cdb4ab67 108 * @return MICROBIT_OK on success, or MICROBIT_INVALID_PARAMETER if the default message bus does not exist.
Jonathan Austin 1:8aa5cdb4ab67 109 *
Jonathan Austin 1:8aa5cdb4ab67 110 * @note MICROBIT_EVT_ANY can be used to deregister all event values matching the given id.
Jonathan Austin 1:8aa5cdb4ab67 111 */
Jonathan Austin 1:8aa5cdb4ab67 112 int MicroBitRadioEvent::ignore(uint16_t id, uint16_t value)
Jonathan Austin 1:8aa5cdb4ab67 113 {
Jonathan Austin 1:8aa5cdb4ab67 114 if (EventModel::defaultEventBus)
Jonathan Austin 1:8aa5cdb4ab67 115 return ignore(id, value, *EventModel::defaultEventBus);
Jonathan Austin 1:8aa5cdb4ab67 116
Jonathan Austin 1:8aa5cdb4ab67 117 return MICROBIT_INVALID_PARAMETER;
Jonathan Austin 1:8aa5cdb4ab67 118 }
Jonathan Austin 1:8aa5cdb4ab67 119
Jonathan Austin 1:8aa5cdb4ab67 120 /**
Jonathan Austin 1:8aa5cdb4ab67 121 * Disassociates the given events with the radio channel.
Jonathan Austin 1:8aa5cdb4ab67 122 *
Jonathan Austin 1:8aa5cdb4ab67 123 * @param id The id of the events to deregister.
Jonathan Austin 1:8aa5cdb4ab67 124 *
Jonathan Austin 1:8aa5cdb4ab67 125 * @param value The value of the event to deregister.
Jonathan Austin 1:8aa5cdb4ab67 126 *
Jonathan Austin 1:8aa5cdb4ab67 127 * @param eventBus The EventModel to deregister on.
Jonathan Austin 1:8aa5cdb4ab67 128 *
Jonathan Austin 1:8aa5cdb4ab67 129 * @return MICROBIT_OK on success.
Jonathan Austin 1:8aa5cdb4ab67 130 *
Jonathan Austin 1:8aa5cdb4ab67 131 * @note MICROBIT_EVT_ANY can be used to deregister all event values matching the given id.
Jonathan Austin 1:8aa5cdb4ab67 132 */
Jonathan Austin 1:8aa5cdb4ab67 133 int MicroBitRadioEvent::ignore(uint16_t id, uint16_t value, EventModel &eventBus)
Jonathan Austin 1:8aa5cdb4ab67 134 {
Jonathan Austin 1:8aa5cdb4ab67 135 return eventBus.ignore(id, value, this, &MicroBitRadioEvent::eventReceived);
Jonathan Austin 1:8aa5cdb4ab67 136 }
Jonathan Austin 1:8aa5cdb4ab67 137
Jonathan Austin 1:8aa5cdb4ab67 138
Jonathan Austin 1:8aa5cdb4ab67 139 /**
Jonathan Austin 1:8aa5cdb4ab67 140 * Protocol handler callback. This is called when the radio receives a packet marked as using the event protocol.
Jonathan Austin 1:8aa5cdb4ab67 141 *
Jonathan Austin 1:8aa5cdb4ab67 142 * This function process this packet, and fires the event contained inside onto the default EventModel.
Jonathan Austin 1:8aa5cdb4ab67 143 */
Jonathan Austin 1:8aa5cdb4ab67 144 void MicroBitRadioEvent::packetReceived()
Jonathan Austin 1:8aa5cdb4ab67 145 {
Jonathan Austin 1:8aa5cdb4ab67 146 FrameBuffer *p = radio.recv();
Jonathan Austin 1:8aa5cdb4ab67 147 MicroBitEvent *e = (MicroBitEvent *) p->payload;
Jonathan Austin 1:8aa5cdb4ab67 148
Jonathan Austin 1:8aa5cdb4ab67 149 suppressForwarding = true;
Jonathan Austin 1:8aa5cdb4ab67 150 e->fire();
Jonathan Austin 1:8aa5cdb4ab67 151 suppressForwarding = false;
Jonathan Austin 1:8aa5cdb4ab67 152
Jonathan Austin 1:8aa5cdb4ab67 153 delete p;
Jonathan Austin 1:8aa5cdb4ab67 154 }
Jonathan Austin 1:8aa5cdb4ab67 155
Jonathan Austin 1:8aa5cdb4ab67 156 /**
Jonathan Austin 1:8aa5cdb4ab67 157 * Event handler callback. This is called whenever an event is received matching one of those registered through
Jonathan Austin 1:8aa5cdb4ab67 158 * the registerEvent() method described above. Upon receiving such an event, it is wrapped into
Jonathan Austin 1:8aa5cdb4ab67 159 * a radio packet and transmitted to any other micro:bits in the same group.
Jonathan Austin 1:8aa5cdb4ab67 160 */
Jonathan Austin 1:8aa5cdb4ab67 161 void MicroBitRadioEvent::eventReceived(MicroBitEvent e)
Jonathan Austin 1:8aa5cdb4ab67 162 {
Jonathan Austin 1:8aa5cdb4ab67 163 if(suppressForwarding)
Jonathan Austin 1:8aa5cdb4ab67 164 return;
Jonathan Austin 1:8aa5cdb4ab67 165
Jonathan Austin 1:8aa5cdb4ab67 166 FrameBuffer buf;
Jonathan Austin 1:8aa5cdb4ab67 167
Jonathan Austin 1:8aa5cdb4ab67 168 buf.length = sizeof(MicroBitEvent) + MICROBIT_RADIO_HEADER_SIZE - 1;
Jonathan Austin 1:8aa5cdb4ab67 169 buf.version = 1;
Jonathan Austin 1:8aa5cdb4ab67 170 buf.group = 0;
Jonathan Austin 1:8aa5cdb4ab67 171 buf.protocol = MICROBIT_RADIO_PROTOCOL_EVENTBUS;
Jonathan Austin 1:8aa5cdb4ab67 172 memcpy(buf.payload, (const uint8_t *)&e, sizeof(MicroBitEvent));
Jonathan Austin 1:8aa5cdb4ab67 173
Jonathan Austin 1:8aa5cdb4ab67 174 radio.send(&buf);
Jonathan Austin 1:8aa5cdb4ab67 175 }