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/* File generated by Beremiz (PlugGenerate_C method of Modbus plugin) */

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     3

/*

     4

 * Copyright (c) 2016 Mario de Sousa (msousa@fe.up.pt)

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 *

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 * This file is part of the Modbus library for Beremiz and matiec.

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 *

     8

 * This Modbus library is free software: you can redistribute it and/or modify

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 * it under the terms of the GNU Lesser General Public License as published by

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 * the Free Software Foundation, either version 2 of the License, or

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 * (at your option) any later version.

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 *

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 * This program is distributed in the hope that it will be useful, but

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 * WITHOUT ANY WARRANTY; without even the implied warranty of

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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser 

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 * General Public License for more details.

    17

 *

    18

 * You should have received a copy of the GNU Lesser General Public License

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 * along with this Modbus library.  If not, see <http://www.gnu.org/licenses/>.

    20

 *

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 * This code is made available on the understanding that it will not be

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 * used in safety-critical situations without a full and competent review.

    23

 */

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    25

    26

#include <stdio.h>

    27

#include <string.h>  /* required for memcpy() */

    28

#include <errno.h>

    29

#include <time.h>

    30

#include <signal.h>

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#include <unistd.h>  /* required for pause() */

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#include "mb_slave_and_master.h"

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#include "MB_%(locstr)s.h"

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    35

    36

#define MAX_MODBUS_ERROR_CODE 11

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static const char *modbus_error_messages[MAX_MODBUS_ERROR_CODE+1] = {

    38

    /* 0 */ "",                             /* un-used -> no error! */

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    /* 1 */ "illegal/unsuported function",

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    /* 2 */ "illegal data address",

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    /* 3 */ "illegal data value",

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    /* 4 */ "slave device failure",

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    /* 5 */ "acknowledge -> slave intends to reply later",

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    /* 6 */ "slave device busy",

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    /* 7 */ "negative acknowledge",

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    /* 8 */ "memory parity error",

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    /* 9 */ "",                             /* undefined by Modbus */

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    /* 10*/ "gateway path unavalilable",

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    /* 11*/ "gateway target device failed to respond"

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};    

    51

    52

    53

/* Execute a modbus client transaction/request */

    54

static int __execute_mb_request(int request_id){

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	switch (client_requests[request_id].mb_function){

    56

    57

	case  1: /* read coils */

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		return read_output_bits(client_requests[request_id].slave_id,

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					client_requests[request_id].address,

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					client_requests[request_id].count,

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					client_requests[request_id].coms_buffer,

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					(int) client_requests[request_id].count,

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					client_nodes[client_requests[request_id].client_node_id].mb_nd,

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					client_requests[request_id].retries,

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					&(client_requests[request_id].mb_error_code),

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					&(client_requests[request_id].resp_timeout),

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					&(client_requests[request_id].coms_buf_mutex));

    68

    69

	case  2: /* read discrete inputs */

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		return read_input_bits( client_requests[request_id].slave_id,

    71

					client_requests[request_id].address,

    72

					client_requests[request_id].count,

    73

					client_requests[request_id].coms_buffer,

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					(int) client_requests[request_id].count,

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					client_nodes[client_requests[request_id].client_node_id].mb_nd,

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					client_requests[request_id].retries,

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					&(client_requests[request_id].mb_error_code),

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					&(client_requests[request_id].resp_timeout),

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					&(client_requests[request_id].coms_buf_mutex));

    80

    81

	case  3: /* read holding registers */

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		return read_output_words(client_requests[request_id].slave_id,

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					client_requests[request_id].address,

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					client_requests[request_id].count,

    85

					client_requests[request_id].coms_buffer,

    86

					(int) client_requests[request_id].count,

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					client_nodes[client_requests[request_id].client_node_id].mb_nd,

    88

					client_requests[request_id].retries,

    89

					&(client_requests[request_id].mb_error_code),

    90

					&(client_requests[request_id].resp_timeout),

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					&(client_requests[request_id].coms_buf_mutex));

    92

    93

	case  4: /* read input registers */

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		return read_input_words(client_requests[request_id].slave_id,

    95

					client_requests[request_id].address,

    96

					client_requests[request_id].count,

    97

					client_requests[request_id].coms_buffer,

    98

					(int) client_requests[request_id].count,

    99

					client_nodes[client_requests[request_id].client_node_id].mb_nd,

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					client_requests[request_id].retries,

   101

					&(client_requests[request_id].mb_error_code),

   102

					&(client_requests[request_id].resp_timeout),

   103

					&(client_requests[request_id].coms_buf_mutex));

   104

   105

	case  5: /* write single coil */

   106

		return write_output_bit(client_requests[request_id].slave_id,

   107

					client_requests[request_id].address,

   108

					client_requests[request_id].coms_buffer[0],

   109

					client_nodes[client_requests[request_id].client_node_id].mb_nd,

   110

					client_requests[request_id].retries,

   111

					&(client_requests[request_id].mb_error_code),

   112

					&(client_requests[request_id].resp_timeout),

   113

					&(client_requests[request_id].coms_buf_mutex));

   114

   115

	case  6: /* write single register */

   116

		return write_output_word(client_requests[request_id].slave_id,

   117

					client_requests[request_id].address,

   118

					client_requests[request_id].coms_buffer[0],

   119

					client_nodes[client_requests[request_id].client_node_id].mb_nd,

   120

					client_requests[request_id].retries,

   121

					&(client_requests[request_id].mb_error_code),

   122

					&(client_requests[request_id].resp_timeout),

   123

					&(client_requests[request_id].coms_buf_mutex));

   124

   125

	case  7: break; /* function not yet supported */

   126

	case  8: break; /* function not yet supported */

   127

	case  9: break; /* function not yet supported */

   128

	case 10: break; /* function not yet supported */

   129

	case 11: break; /* function not yet supported */

   130

	case 12: break; /* function not yet supported */

   131

	case 13: break; /* function not yet supported */

   132

	case 14: break; /* function not yet supported */

   133

   134

	case 15: /* write multiple coils */

   135

		return write_output_bits(client_requests[request_id].slave_id,

   136

					 client_requests[request_id].address,

   137

					 client_requests[request_id].count,

   138

					 client_requests[request_id].coms_buffer,

   139

					 client_nodes[client_requests[request_id].client_node_id].mb_nd,

   140

					 client_requests[request_id].retries,

   141

					 &(client_requests[request_id].mb_error_code),

   142

					 &(client_requests[request_id].resp_timeout),

   143

					 &(client_requests[request_id].coms_buf_mutex));

   144

   145

	case 16: /* write multiple registers */

   146

		return write_output_words(client_requests[request_id].slave_id,

   147

					client_requests[request_id].address,

   148

					client_requests[request_id].count,

   149

					client_requests[request_id].coms_buffer,

   150

					client_nodes[client_requests[request_id].client_node_id].mb_nd,

   151

					client_requests[request_id].retries,

   152

					&(client_requests[request_id].mb_error_code),

   153

					&(client_requests[request_id].resp_timeout),

   154

					&(client_requests[request_id].coms_buf_mutex));

   155

   156

	default: break;  /* should never occur, if file generation is correct */

   157

	}

   158

   159

	fprintf(stderr, "Modbus plugin: Modbus function %%d not supported\n", request_id); /* should never occur, if file generation is correct */

   160

	return -1;

   161

}

   162

   163

   164

   165

/* pack bits from unpacked_data to packed_data */

   166

static inline int __pack_bits(u16 *unpacked_data, u16 start_addr, u16 bit_count,  u8  *packed_data) {

   167

  u8 bit;

   168

  u16 byte, coils_processed;

   169

   170

  if ((0 == bit_count) || (65535-start_addr < bit_count-1))

   171

    return -ERR_ILLEGAL_DATA_ADDRESS; /* ERR_ILLEGAL_DATA_ADDRESS defined in mb_util.h */

   172

   173

  for( byte = 0, coils_processed = 0; coils_processed < bit_count; byte++) {

   174

    packed_data[byte] = 0;

   175

    for( bit = 0x01; (bit & 0xFF) && (coils_processed < bit_count); bit <<= 1, coils_processed++ ) {

   176

      if(unpacked_data[start_addr + coils_processed])

   177

            packed_data[byte] |=  bit; /*   set bit */

   178

      else  packed_data[byte] &= ~bit; /* reset bit */

   179

    }

   180

  }

   181

  return 0;

   182

}

   183

   184

   185

/* unpack bits from packed_data to unpacked_data */

   186

static inline int __unpack_bits(u16 *unpacked_data, u16 start_addr, u16 bit_count,  u8  *packed_data) {

   187

  u8  temp, bit;

   188

  u16 byte, coils_processed;

   189

   190

  if ((0 == bit_count) || (65535-start_addr < bit_count-1))

   191

    return -ERR_ILLEGAL_DATA_ADDRESS; /* ERR_ILLEGAL_DATA_ADDRESS defined in mb_util.h */

   192

   193

  for(byte = 0, coils_processed = 0; coils_processed < bit_count; byte++) {

   194

    temp = packed_data[byte] ;

   195

    for(bit = 0x01; (bit & 0xff) && (coils_processed < bit_count); bit <<= 1, coils_processed++) {

   196

      unpacked_data[start_addr + coils_processed] = (temp & bit)?1:0;

   197

    }

   198

  }

   199

  return 0;

   200

}

   201

   202

   203

static int __read_inbits   (void *mem_map, u16 start_addr, u16 bit_count, u8  *data_bytes)

   204

  {return   __pack_bits(((server_mem_t *)mem_map)->ro_bits, start_addr, bit_count, data_bytes);}

   205

static int __read_outbits  (void *mem_map, u16 start_addr, u16 bit_count, u8  *data_bytes)

   206

  {return   __pack_bits(((server_mem_t *)mem_map)->rw_bits, start_addr, bit_count, data_bytes);}

   207

static int __write_outbits (void *mem_map, u16 start_addr, u16 bit_count, u8  *data_bytes)

   208

  {return __unpack_bits(((server_mem_t *)mem_map)->rw_bits, start_addr, bit_count, data_bytes); }

   209

   210

   211

   212

static int __read_inwords  (void *mem_map, u16 start_addr, u16 word_count, u16 *data_words) {

   213

   214

  if ((start_addr + word_count) > MEM_AREA_SIZE)

   215

    return -ERR_ILLEGAL_DATA_ADDRESS; /* ERR_ILLEGAL_DATA_ADDRESS defined in mb_util.h */

   216

   217

  /* use memcpy() because loop with pointers (u16 *) caused alignment problems */

   218

  memcpy(/* dest */ (void *)data_words,

   219

         /* src  */ (void *)&(((server_mem_t *)mem_map)->ro_words[start_addr]),

   220

         /* size */ word_count * 2);

   221

  return 0;

   222

}

   223

   224

   225

   226

static int __read_outwords (void *mem_map, u16 start_addr, u16 word_count, u16 *data_words) {

   227

   228

  if ((start_addr + word_count) > MEM_AREA_SIZE)

   229

    return -ERR_ILLEGAL_DATA_ADDRESS; /* ERR_ILLEGAL_DATA_ADDRESS defined in mb_util.h */

   230

   231

  /* use memcpy() because loop with pointers (u16 *) caused alignment problems */

   232

  memcpy(/* dest */ (void *)data_words,

   233

         /* src  */ (void *)&(((server_mem_t *)mem_map)->rw_words[start_addr]),

   234

         /* size */ word_count * 2);

   235

  return 0;

   236

}

   237

   238

   239

   240

   241

static int __write_outwords(void *mem_map, u16 start_addr, u16 word_count, u16 *data_words) {

   242

   243

  if ((start_addr + word_count) > MEM_AREA_SIZE)

   244

    return -ERR_ILLEGAL_DATA_ADDRESS; /* ERR_ILLEGAL_DATA_ADDRESS defined in mb_util.h */

   245

   246

  /* WARNING: The data returned in the data_words[] array is not guaranteed to be 16 bit aligned.

   247

   *           It is not therefore safe to cast it to an u16 data type.

   248

   *           The following code cannot be used. memcpy() is used instead.

   249

   */

   250

  /*

   251

  for (count = 0; count < word_count ; count++)

   252

    ((server_mem_t *)mem_map)->rw_words[count + start_addr] = data_words[count];

   253

  */

   254

  memcpy(/* dest */ (void *)&(((server_mem_t *)mem_map)->rw_words[start_addr]),

   255

         /* src  */ (void *)data_words,

   256

         /* size */ word_count * 2);

   257

  return 0;

   258

}

   259

   260

   261

   262

   263

#include <pthread.h>

   264

   265

static void *__mb_server_thread(void *_server_node)  {

   266

	server_node_t *server_node = _server_node;

   267

	mb_slave_callback_t callbacks = { 

   268

			&__read_inbits,

   269

			&__read_outbits,

   270

			&__write_outbits,

   271

			&__read_inwords,

   272

			&__read_outwords,

   273

			&__write_outwords,

   274

			(void *)&(server_node->mem_area)

   275

			};  

   276

   277

	// Enable thread cancelation. Enabled is default, but set it anyway to be safe.

   278

	pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);

   279

   280

	// mb_slave_run() should never return!

   281

	mb_slave_run(server_node->mb_nd /* nd */, callbacks, server_node->slave_id);

   282

	fprintf(stderr, "Modbus plugin: Modbus server for node %%s died unexpectedly!\n", server_node->location); /* should never occur */

   283

	return NULL;

   284

}

   285

   286

   287

#define timespec_add(ts, sec, nsec) {		\

   288

	ts.tv_sec  +=  sec;			\

   289

	ts.tv_nsec += nsec;			\

   290

	if (ts.tv_nsec >= 1000000000) {		\

   291

		ts.tv_sec  ++;			\

   292

		ts.tv_nsec -= 1000000000;	\

   293

	}					\

   294

}

   295

   296

   297

static void *__mb_client_thread(void *_index)  {

   298

	int client_node_id = (char *)_index - (char *)NULL; // Use pointer arithmetic (more portable than cast)

   299

   300

	// Enable thread cancelation. Enabled is default, but set it anyway to be safe.

   301

	pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);

   302

   303

    /* loop the communication with the client

   304

     * 

   305

         * When the client thread has difficulty communicating with remote client and/or server (network issues, for example),

   306

         * then the communications get delayed and we will fall behind in the period. 

   307

         * 

   308

         * This is OK. Note that if the condition variable were to be signaled multiple times while the client thread is inside the same

   309

         * Modbus transaction, then all those signals would be ignored.

   310

         * However, and since we keep the mutex locked during the communication cycle, it is not possible to signal the condition variable

   311

         * during that time (it is only possible while the thread is blocked during the call to pthread_cond_wait().

   312

         * 

   313

         * This means that when network issues eventually get resolved, we will NOT have a bunch of delayed activations to handle

   314

         * in quick succession (which would goble up CPU time). 

   315

         * 

   316

         * Notice that the above property is valid whether the communication cycle is run with the mutex locked, or unlocked.

   317

         * Since it makes it easier to implement the correct semantics for the other activation methods if the communication cycle

   318

         * is run with the mutex locked, then that is what we do.

   319

         * 

   320

     * Note that during all the communication cycle we will keep locked the mutex 

   321

     * (i.e. the mutex used together with the condition variable that will activate a new communication cycle)

   322

     * 

   323

     * Note that we never get to explicitly unlock this mutex. It will only be unlocked by the pthread_cond_wait()

   324

     * call at the end of the cycle.

   325

     */

   326

    pthread_mutex_lock(&(client_nodes[client_node_id].mutex));

   327

   328

	while (1) {

   329

		/*

   330

		struct timespec cur_time;

   331

		clock_gettime(CLOCK_MONOTONIC, &cur_time);

   332

		fprintf(stderr, "Modbus client thread (%%d) - new cycle (%%ld:%%ld)!\n", client_node_id, cur_time.tv_sec, cur_time.tv_nsec);

   333

		*/

   334

		int req;

   335

		for (req=0; req < NUMBER_OF_CLIENT_REQTS; req ++){

   336

			/* just do the requests belonging to the client */

   337

			if (client_requests[req].client_node_id != client_node_id)

   338

				continue;

   339

   340

            /* only do the request if:

   341

             *   - this request was explictly asked to be executed by the client program

   342

             *  OR

   343

             *   - the client thread was activated periodically

   344

             *     (in which case we execute all the requests belonging to the client node)

   345

             */

   346

            if ((client_requests[req].flag_exec_req == 0) && (client_nodes[client_requests[req].client_node_id].periodic_act == 0))

   347

                continue;

   348

   349

            /*

   350

            fprintf(stderr, "Modbus client thread (%%d): RUNNING Modbus request %%d  (periodic = %%d  flag_exec_req = %%d)\n", 

   351

                    client_node_id, req, client_nodes[client_requests[req].client_node_id].periodic_act, client_requests[req].flag_exec_req );

   352

            */

   353

   354

			int res_tmp = __execute_mb_request(req);

   355

			client_requests[req].tn_error_code = 0; // assume success

   356

			switch (res_tmp) {

   357

			  case PORT_FAILURE: {

   358

				if (res_tmp != client_nodes[client_node_id].prev_error)

   359

					fprintf(stderr, "Modbus plugin: Error connecting Modbus client %%s to remote server.\n", client_nodes[client_node_id].location);

   360

				client_nodes[client_node_id].prev_error = res_tmp;

   361

				client_requests[req].tn_error_code = 1; // error accessing IP network, or serial interface

   362

				break;

   363

			  }

   364

			  case INVALID_FRAME: {

   365

				if ((res_tmp != client_requests[req].prev_error) && (0 == client_nodes[client_node_id].prev_error))

   366

					fprintf(stderr, "Modbus plugin: Modbus client request configured at location %%s was unsuccesful. Server/slave returned an invalid/corrupted frame.\n", client_requests[req].location);

   367

				client_requests[req].prev_error = res_tmp;

   368

				client_requests[req].tn_error_code = 2; // reply received from server was an invalid frame

   369

				break;

   370

			  }

   371

			  case TIMEOUT: {

   372

				if ((res_tmp != client_requests[req].prev_error) && (0 == client_nodes[client_node_id].prev_error))

   373

					fprintf(stderr, "Modbus plugin: Modbus client request configured at location %%s timed out waiting for reply from server.\n", client_requests[req].location);

   374

				client_requests[req].prev_error = res_tmp;

   375

				client_requests[req].tn_error_code = 3; // server did not reply before timeout expired

   376

				break;

   377

			  }

   378

			  case MODBUS_ERROR: {

   379

				if (client_requests[req].prev_error != client_requests[req].mb_error_code) {

   380

					fprintf(stderr, "Modbus plugin: Modbus client request configured at location %%s was unsuccesful. Server/slave returned error code 0x%%2x", client_requests[req].location, client_requests[req].mb_error_code);

   381

					if (client_requests[req].mb_error_code <= MAX_MODBUS_ERROR_CODE ) {

   382

						fprintf(stderr, "(%%s)", modbus_error_messages[client_requests[req].mb_error_code]);

   383

						fprintf(stderr, ".\n");

   384

					}

   385

				}

   386

				client_requests[req].prev_error = client_requests[req].mb_error_code;

   387

				client_requests[req].tn_error_code = 4; // server returned a valid Modbus error frame

   388

				break;

   389

			  }

   390

			  default: {

   391

				if ((res_tmp >= 0) && (client_nodes[client_node_id].prev_error != 0)) {

   392

					fprintf(stderr, "Modbus plugin: Modbus client %%s has reconnected to server/slave.\n", client_nodes[client_node_id].location);

   393

				}

   394

				if ((res_tmp >= 0) && (client_requests[req]        .prev_error != 0)) {

   395

					fprintf(stderr, "Modbus plugin: Modbus client request configured at location %%s has succesfully resumed comunication.\n", client_requests[req].location);

   396

				}

   397

				client_nodes[client_node_id].prev_error = 0;

   398

				client_requests[req]        .prev_error = 0;

   399

				break;

   400

			  }

   401

			}

   402

   403

			/* Set the flag_tn_error_code and flag_mb_error_code that are mapped onto

   404

             * located BYTE variables, so the user program

   405

             * knows how the communication is going.

   406

             */

   407

            client_requests[req].flag_mb_error_code = client_requests[req].mb_error_code;

   408

            client_requests[req].flag_tn_error_code = client_requests[req].tn_error_code;

   409

   410

            /* We have just finished excuting a client transcation request.

   411

             * If the current cycle was activated by user request we reset the flag used to ask to run it

   412

             */

   413

            if (0 != client_requests[req].flag_exec_req) {

   414

                client_requests[req].flag_exec_req     = 0;

   415

                client_requests[req].flag_exec_started = 0;   

   416

            }

   417

   418

            //fprintf(stderr, "Modbus plugin: RUNNING<---> of Modbus request %%d  (periodic = %%d  flag_exec_req = %%d)\n", 

   419

            //        req, client_nodes[client_requests[req].client_node_id].periodic_act, client_requests[req].flag_exec_req );

   420

        }

   421

   422

        // Wait for signal (from timer or explicit request from user program) before starting the next cycle

   423

        {

   424

            // No need to lock the mutex. Is is already locked just before the while(1) loop.

   425

            // Read the comment there to understand why.

   426

            // pthread_mutex_lock(&(client_nodes[client_node_id].mutex));

   427

   428

            /* the client thread has just finished a cycle, so all the flags used to signal an activation

   429

             * and specify the activation source (periodic, user request, ...)

   430

             * get reset here, before waiting for a new activation.

   431

             */

   432

            client_nodes[client_node_id].periodic_act = 0;            

   433

            client_nodes[client_node_id].execute_req  = 0;

   434

   435

            while (client_nodes[client_node_id].execute_req == 0)

   436

                pthread_cond_wait(&(client_nodes[client_node_id].condv),

   437

                                &(client_nodes[client_node_id].mutex)); 

   438

   439

            // We run the communication cycle with the mutex locked.

   440

            // Read the comment just above the while(1) to understand why.

   441

            // pthread_mutex_unlock(&(client_nodes[client_node_id].mutex));

   442

        }

   443

	}

   444

   445

	// humour the compiler.

   446

	return NULL;

   447

}

   448

   449

   450

   451

   452

   453

/* Thread that simply implements a periodic 'timer',

   454

 *  i.e. periodically sends signal to the  thread running __mb_client_thread()

   455

 * 

   456

 * Note that we do not use a posix timer (timer_create() ) because there doesn't seem to be a way

   457

 * of having the timer notify the thread that is portable across Xenomai and POSIX.

   458

 * - SIGEV_THREAD    : not supported by Xenomai

   459

 * - SIGEV_THREAD_ID : Linux specific (i.e. non POSIX)

   460

 *                     Even so, I did not get it to work under Linux (issues with the header files)

   461

 * - SIGEV_SIGNAL    : Will not work, as signal is sent to random thread in process!

   462

 */

   463

static void *__mb_client_timer_thread(void *_index) {

   464

	int client_node_id = (char *)_index - (char *)NULL; // Use pointer arithmetic (more portable than cast)

   465

	struct timespec next_cycle;

   466

   467

	int period_sec  =  client_nodes[client_node_id].comm_period / 1000;          /* comm_period is in ms */

   468

	int period_nsec = (client_nodes[client_node_id].comm_period %%1000)*1000000; /* comm_period is in ms */

   469

   470

	// Enable thread cancelation. Enabled is default, but set it anyway to be safe.

   471

	pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);

   472

   473

    if (client_nodes[client_node_id].comm_period <= 0) {

   474

        // No periodic activation required => nothing to do! 

   475

        while (1) pause(); // wait to be canceled when program terminates (shutdown() is called)

   476

        return NULL;  // not really necessary, just makes it easier to understand the code.

   477

    }

   478

   479

	// get the current time

   480

	clock_gettime(CLOCK_MONOTONIC, &next_cycle);

   481

   482

    while(1) {

   483

        // Determine absolute time instant for starting the next cycle

   484

        struct timespec prev_cycle, now;

   485

        prev_cycle = next_cycle;

   486

        timespec_add(next_cycle, period_sec, period_nsec);

   487

   488

        /* NOTE:

   489

         * It is probably un-necessary to check for overflow of timer!

   490

         * Even in 32 bit systems this will take at least 68 years since the computer booted

   491

         * (remember, we are using CLOCK_MONOTONIC, which should start counting from 0