aboutsummaryrefslogtreecommitdiffstats
path: root/libs/uds-c/src/uds/uds.c
blob: 0114384d525270fdaf2136385e007c65d3b182be (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
#include <uds/uds.h>
#include <bitfield/bitfield.h>
#include <canutil/read.h>
#include <string.h>
#include <limits.h>
#include <stddef.h>
#include <sys/param.h>
#include <inttypes.h>

#define ARBITRATION_ID_OFFSET 0x8
#define MODE_RESPONSE_OFFSET 0x40
#define NEGATIVE_RESPONSE_MODE 0x7f
#define MAX_DIAGNOSTIC_PAYLOAD_SIZE 6
#define MODE_BYTE_INDEX 0
#define PID_BYTE_INDEX 1
#define NEGATIVE_RESPONSE_MODE_INDEX 1
#define NEGATIVE_RESPONSE_NRC_INDEX 2

#ifndef MAX
#define MAX(x, y) (((x) > (y)) ? (x) : (y))
#endif

DiagnosticShims diagnostic_init_shims(LogShim log,
        SendCanMessageShim send_can_message,
        SetTimerShim set_timer) {
    DiagnosticShims shims = {
        log: log,
        send_can_message: send_can_message,
        set_timer: set_timer
    };
    return shims;
}

static void setup_receive_handle(DiagnosticRequestHandle* handle) {
    if(handle->request.arbitration_id == OBD2_FUNCTIONAL_BROADCAST_ID) {
        uint32_t response_id;
        for(response_id = 0;
                response_id < OBD2_FUNCTIONAL_RESPONSE_COUNT; ++response_id) {
            handle->isotp_receive_handles[response_id] = isotp_receive(
                    &handle->isotp_shims,
                    OBD2_FUNCTIONAL_RESPONSE_START + response_id,
                    NULL);
        }
        handle->isotp_receive_handle_count = OBD2_FUNCTIONAL_RESPONSE_COUNT;
    } else {
        handle->isotp_receive_handle_count = 1;
        handle->isotp_receive_handles[0] = isotp_receive(&handle->isotp_shims,
                handle->request.arbitration_id + ARBITRATION_ID_OFFSET,
                NULL);
    }
}

static uint16_t autoset_pid_length(uint8_t mode, uint16_t pid,
        uint8_t pid_length) {
    if(pid_length == 0) {
        if(mode <= 0xa || mode == 0x3e ) {
            pid_length = 1;
        } else if(pid > 0xffff || ((pid & 0xFF00) > 0x0)) {
            pid_length = 2;
        } else {
            pid_length = 1;
        }
    }
    return pid_length;
}

static void send_diagnostic_request(DiagnosticShims* shims,
        DiagnosticRequestHandle* handle) {
    uint8_t payload[MAX_DIAGNOSTIC_PAYLOAD_SIZE] = {0};
    payload[MODE_BYTE_INDEX] = handle->request.mode;
    if(handle->request.has_pid) {
        handle->request.pid_length = autoset_pid_length(handle->request.mode,
                handle->request.pid, handle->request.pid_length);
        set_bitfield(handle->request.pid, PID_BYTE_INDEX * CHAR_BIT,
                handle->request.pid_length * CHAR_BIT, payload,
                sizeof(payload));
    }

    if(handle->request.payload_length > 0) {
        memcpy(&payload[PID_BYTE_INDEX + handle->request.pid_length],
                handle->request.payload, handle->request.payload_length);
    }

    handle->isotp_send_handle = isotp_send(&handle->isotp_shims,
            handle->request.arbitration_id, payload,
            1 + handle->request.payload_length + handle->request.pid_length,
            NULL);
    if(handle->isotp_send_handle.completed &&
            !handle->isotp_send_handle.success) {
        handle->completed = true;
        handle->success = false;
        if(shims->log != NULL) {
            shims->log("%s", "Diagnostic request not sent");
        }
    } else if(shims->log != NULL) {
        char request_string[128] = {0};
        diagnostic_request_to_string(&handle->request, request_string,
                sizeof(request_string));
        shims->log("Sending diagnostic request: %s", request_string);
    }
}

bool diagnostic_request_sent(DiagnosticRequestHandle* handle) {
    return handle->isotp_send_handle.completed;
}

void start_diagnostic_request(DiagnosticShims* shims,
        DiagnosticRequestHandle* handle) {
    handle->success = false;
    handle->completed = false;
    send_diagnostic_request(shims, handle);
    if(!handle->completed) {
        setup_receive_handle(handle);
    }
}

DiagnosticRequestHandle generate_diagnostic_request(DiagnosticShims* shims,
        DiagnosticRequest* request, DiagnosticResponseReceived callback) {
    DiagnosticRequestHandle handle = {
        request: *request,
        callback: callback,
        success: false,
        completed: false
    };

    handle.isotp_shims = isotp_init_shims(shims->log,
            shims->send_can_message,
            shims->set_timer);
    handle.isotp_shims.frame_padding = !request->no_frame_padding;

    return handle;
    // TODO notes on multi frame:
    // TODO what are the timers for exactly?
    //
    // when sending multi frame, send 1 frame, wait for a response
    // if it says send all, send all right away
    // if it says flow control, set the time for the next send
    // instead of creating a timer with an async callback, add a process_handle
    // function that's called repeatedly in the main loop - if it's time to
    // send, we do it. so there's a process_handle_send and receive_can_frame
    // that are just called continuously from the main loop. it's a waste of a
    // few cpu cycles but it may be more  natural than callbacks.
    //
    // what would a timer callback look like...it would need to pass the handle
    // and that's all. seems like a context void* would be able to capture all
    // of the information but arg, memory allocation. look at how it's done in
    // the other library again
    //
}

DiagnosticRequestHandle diagnostic_request(DiagnosticShims* shims,
        DiagnosticRequest* request, DiagnosticResponseReceived callback) {
    DiagnosticRequestHandle handle = generate_diagnostic_request(
            shims, request, callback);
    start_diagnostic_request(shims, &handle);
    return handle;
}

DiagnosticRequestHandle diagnostic_request_pid(DiagnosticShims* shims,
        DiagnosticPidRequestType pid_request_type, uint32_t arbitration_id,
        uint16_t pid, DiagnosticResponseReceived callback) {
    DiagnosticRequest request = {
        arbitration_id: arbitration_id,
        mode: pid_request_type == DIAGNOSTIC_STANDARD_PID ? 0x1 : 0x22,
        has_pid: true,
        pid: pid
    };

    return diagnostic_request(shims, &request, callback);
}

static bool handle_negative_response(IsoTpMessage* message,
        DiagnosticResponse* response, DiagnosticShims* shims) {
    bool response_was_negative = false;
    if(response->mode == NEGATIVE_RESPONSE_MODE) {
        response_was_negative = true;
        if(message->size > NEGATIVE_RESPONSE_MODE_INDEX) {
            response->mode = message->payload[NEGATIVE_RESPONSE_MODE_INDEX];
        }

        if(message->size > NEGATIVE_RESPONSE_NRC_INDEX) {
            response->negative_response_code =
                    message->payload[NEGATIVE_RESPONSE_NRC_INDEX];
        }

        response->success = false;
        response->completed = true;
    }
    return response_was_negative;
}

static bool handle_positive_response(DiagnosticRequestHandle* handle,
        IsoTpMessage* message, DiagnosticResponse* response,
        DiagnosticShims* shims) {
    bool response_was_positive = false;
    if(response->mode == handle->request.mode + MODE_RESPONSE_OFFSET) {
        response_was_positive = true;
        // hide the "response" version of the mode from the user
        // if it matched
        response->mode = handle->request.mode;
        response->has_pid = false;
        if(handle->request.has_pid && message->size > 1) {
            response->has_pid = true;
            if(handle->request.pid_length == 2) {
                response->pid = get_bitfield(message->payload, message->size,
                        PID_BYTE_INDEX * CHAR_BIT, sizeof(uint16_t) * CHAR_BIT);
            } else {
                response->pid = message->payload[PID_BYTE_INDEX];
            }

        }

        if((!handle->request.has_pid && !response->has_pid)
                || response->pid == handle->request.pid) {
            response->success = true;
            response->completed = true;

            uint8_t payload_index = 1 + handle->request.pid_length;
            response->payload_length = MAX(0, message->size - payload_index);
            if(response->payload_length > 0) {
                memcpy(response->payload, &message->payload[payload_index],
                        response->payload_length);
            }
        } else {
            response_was_positive = false;
        }
    }
    return response_was_positive;
}

DiagnosticResponse diagnostic_receive_can_frame(DiagnosticShims* shims,
        DiagnosticRequestHandle* handle, const uint32_t arbitration_id,
        const uint8_t data[], const uint8_t size) {

    DiagnosticResponse response = {
        arbitration_id: arbitration_id,
        multi_frame: false,
        success: false,
        completed: false
    };

    if(!handle->isotp_send_handle.completed) {
        isotp_continue_send(&handle->isotp_shims,
                &handle->isotp_send_handle, arbitration_id, data, size);
    } else {
        uint8_t i;
        for(i = 0; i < handle->isotp_receive_handle_count; ++i) {
            IsoTpMessage message = isotp_continue_receive(&handle->isotp_shims,
                    &handle->isotp_receive_handles[i], arbitration_id, data,
                    size);
            response.multi_frame = message.multi_frame;

            if(message.completed) {
                if(message.size > 0) {
                    response.mode = message.payload[0];
                    if(handle_negative_response(&message, &response, shims) ||
                            handle_positive_response(handle, &message,
                                &response, shims)) {
                        if(shims->log != NULL) {
                            char response_string[128] = {0};
                            diagnostic_response_to_string(&response,
                                    response_string, sizeof(response_string));
                            shims->log("Diagnostic response received: %s",
                                    response_string);
                        }

                        handle->success = true;
                        handle->completed = true;
                    }
                } else {
                    if(shims->log != NULL) {
                        shims->log("Received an empty response on arb ID 0x%x",
                                response.arbitration_id);
                    }
                }

                if(handle->completed && handle->callback != NULL) {
                    handle->callback(&response);
                }

                break;
            }
        }
    }
    return response;
}

int diagnostic_payload_to_integer(const DiagnosticResponse* response) {
    return get_bitfield(response->payload, response->payload_length, 0,
            response->payload_length * CHAR_BIT);
}

float diagnostic_decode_obd2_pid(const DiagnosticResponse* response) {
    // handles on the single number values, not the bit encoded ones
    switch(response->pid) {
        case 0xa:
            return response->payload[0] * 3;
        case 0xc:
            return (response->payload[0] * 256 + response->payload[1]) / 4.0;
        case 0xd:
        case 0x33:
        case 0xb:
            return response->payload[0];
        case 0x10:
            return (response->payload[0] * 256 + response->payload[1]) / 100.0;
        case 0x11:
        case 0x2f:
        case 0x45:
        case 0x4c:
        case 0x52:
        case 0x5a:
        case 0x4:
            return response->payload[0] * 100.0 / 255.0;
        case 0x46:
        case 0x5c:
        case 0xf:
        case 0x5:
            return response->payload[0] - 40;
        case 0x62:
            return response->payload[0] - 125;
        default:
            return diagnostic_payload_to_integer(response);
    }
}

void diagnostic_response_to_string(const DiagnosticResponse* response,
        char* destination, size_t destination_length) {
    int bytes_used = snprintf(destination, destination_length,
            "arb_id: 0x%lx, mode: 0x%x, ",
            (unsigned long) response->arbitration_id,
            response->mode);

    if(response->has_pid) {
        bytes_used += snprintf(destination + bytes_used,
                destination_length - bytes_used,
                "pid: 0x%x, ",
                response->pid);
    }

    if(!response->success) {
        bytes_used += snprintf(destination + bytes_used,
                destination_length - bytes_used,
                "nrc: 0x%x, ",
                response->negative_response_code);
    }

    if(response->payload_length > 0) {
        snprintf(destination + bytes_used, destination_length - bytes_used,
                "payload: 0x%02x%02x%02x%02x%02x%02x%02x",
                response->payload[0],
                response->payload[1],
                response->payload[2],
                response->payload[3],
                response->payload[4],
                response->payload[5],
                response->payload[6]);
    } else {
        snprintf(destination + bytes_used, destination_length - bytes_used,
                "no payload");
    }
}

void diagnostic_request_to_string(const DiagnosticRequest* request,
        char* destination, size_t destination_length) {
    int bytes_used = snprintf(destination, destination_length,
            "arb_id: 0x%lx, mode: 0x%x, ",
            (unsigned long) request->arbitration_id,
            request->mode);

    if(request->has_pid) {
        bytes_used += snprintf(destination + bytes_used,
                destination_length - bytes_used,
                "pid: 0x%x, ",
                request->pid);
    }

    int remaining_space = destination_length - bytes_used;
    if(request->payload_length > 0) {
        snprintf(destination + bytes_used, remaining_space,
                "payload: 0x%02x%02x%02x%02x%02x%02x%02x",
                request->payload[0],
                request->payload[1],
                request->payload[2],
                request->payload[3],
                request->payload[4],
                request->payload[5],
                request->payload[6]);
    } else {
        snprintf(destination + bytes_used, remaining_space, "no payload");
    }
}

bool diagnostic_request_equals(const DiagnosticRequest* ours,
        const DiagnosticRequest* theirs) {
    bool equals = ours->arbitration_id == theirs->arbitration_id &&
        ours->mode == theirs->mode;
    equals &= ours->has_pid == theirs->has_pid;
    equals &= ours->pid == theirs->pid;
    return equals;
}