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comparison LossyCom.h @ 0:29d8b41926f0

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Initial commit - compiles but has still the wrong name
author Merten Sach <msach@mailbox.tu-berlin.de>
date Wed, 07 Mar 2012 19:46:37 +0100
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children 826448e34e80
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-1:000000000000 0:b07c8ec4360a
1 /*
2 * This describes a best effort communication channel. Mainly designed for
3 * communication between Core-Controllers, so they can inform each other about
4 * their status and pass work around. This is to avoid idling cores that occupy
5 * the Masterlock.
6 *
7 * The communication entities poll a central trigger counter that increases when
8 * there are new messages. However it's not guaranteed that the increase of the
9 * counter reflects the number of new messages.
10 *
11 * The messages consist of a single 64bit word so it can be written in one
12 * operation and therefore avoiding inconsistent messages.
13 *
14 * The messages are handled with a handler function provided by the receiver
15 * when acquiring the communication endpoint.
16 *
17 * The message passing is handled by a central struct that is used w/o any lock.
18 * It consists of a array messages for the number of communicating entities. The
19 * number of entities is fixed at initialization.
20 */
21
22 #include <stdint.h>
23
24
25
26 /***********************************
27 * Type Definitions
28 ***********************************/
29
30 #define BROADCAST_ID 65535
31 #define ENDPOINT_ID_SHIFT 32
32 #define TRIGGER_SHIFT 48
33
34 /*
35 * A message consists of the
36 * 16bit saved trigger value when the message was sent
37 * 16bit receiver identifier, this is the index of the slot in the array
38 * 65536 is the broadcast identifier
39 * 32bit message body, the message format is defined by the endpoints
40 */
41 typedef uint64_t lossyCom__msg_t;
42 typedef uint32_t lossyCom__msgBody_t;
43 typedef uint16_t lossyCom__endpointID_t;
44
45 /*
46 * Message Handler that has two arguments the sender endpoint ID and the Msg
47 * Example:
48 * void handler_func(lossyCom__endpointID_t senderID, lossyCom__msgBody_t msg);
49 */
50 typedef void (*lossyCom__msgHandler) (lossyCom__endpointID_t, lossyCom__msgBody_t);
51
52 /*
53 * Central communication structure.
54 */
55 typedef struct{
56 uint16_t triggerCounter;
57 uint16_t numEndpoints;
58 lossyCom__msg_t* outboxArray;
59 }lossyCom__exchange_t;
60
61 /*
62 * Endpoint data structure.
63 */
64 typedef struct {
65 uint16_t localTriggerCopy;
66 lossyCom__endpointID_t endpointID;
67 lossyCom__exchange_t* centralExchangePtr;
68 lossyCom__msgHandler* msgHandler;
69 } lossyCom__endpoint_t;
70
71 /***********************************
72 * Function Declarations
73 ***********************************/
74
75 lossyCom__exchange_t* lossyCom__initialize(uint16_t numEndpoints);
76
77 void lossyCom__initialize_endpoint(lossyCom__endpoint_t* localEndpoint,
78 lossyCom__exchange_t* exchange,
79 lossyCom__endpointID_t endpointID,
80 lossyCom__msgHandler* msgHandler);
81
82 void lossyCom__broadcastMsg(lossyCom__endpoint_t* localEndpoint,
83 lossyCom__msgBody_t msg);
84
85 void lossyCom__sendMsg(lossyCom__endpoint_t* localEndpoint,
86 lossyCom__endpointID_t receiverEndpointID,
87 lossyCom__msgBody_t msg);
88
89 void lossyCom__receiveMsg(lossyCom__endpoint_t* localEndpoint);