Continue fixing deadlock of previous commit, this time occuring when waiting for 'cleanup' python runtime call to finish. Now 'init' and 'cleanup' python runtime calls are called directly from main thread, and aren't anymore invoked in the context of wxMainloop and/or twisted reactor.
/* File generated by Beremiz (PlugGenerate_C method of Modbus plugin) */
/*
* Copyright (c) 2016 Mario de Sousa (msousa@fe.up.pt)
*
* This file is part of the Modbus library for Beremiz and matiec.
*
* This Modbus library is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 2 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 Lesser
* General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this Modbus library. If not, see <http://www.gnu.org/licenses/>.
*
* This code is made available on the understanding that it will not be
* used in safety-critical situations without a full and competent review.
*/
#include <stdio.h>
#include <string.h> /* required for memcpy() */
#include "mb_slave_and_master.h"
#include "MB_%(locstr)s.h"
#define MAX_MODBUS_ERROR_CODE 11
static const char *modbus_error_messages[MAX_MODBUS_ERROR_CODE+1] = {
/* 0 */ "", /* un-used -> no error! */
/* 1 */ "illegal/unsuported function",
/* 2 */ "illegal data address",
/* 3 */ "illegal data value",
/* 4 */ "slave device failure",
/* 5 */ "acknowledge -> slave intends to reply later",
/* 6 */ "slave device busy",
/* 7 */ "negative acknowledge",
/* 8 */ "memory parity error",
/* 9 */ "", /* undefined by Modbus */
/* 10*/ "gateway path unavalilable",
/* 11*/ "gateway target device failed to respond"
};
/* Execute a modbus client transaction/request */
static int __execute_mb_request(int request_id){
switch (client_requests[request_id].mb_function){
case 1: /* read coils */
return read_output_bits(client_requests[request_id].slave_id,
client_requests[request_id].address,
client_requests[request_id].count,
client_requests[request_id].coms_buffer,
(int) client_requests[request_id].count,
client_nodes[client_requests[request_id].client_node_id].mb_nd,
client_requests[request_id].retries,
&(client_requests[request_id].error_code),
&(client_requests[request_id].resp_timeout),
&(client_requests[request_id].coms_buf_mutex));
case 2: /* read discrete inputs */
return read_input_bits( client_requests[request_id].slave_id,
client_requests[request_id].address,
client_requests[request_id].count,
client_requests[request_id].coms_buffer,
(int) client_requests[request_id].count,
client_nodes[client_requests[request_id].client_node_id].mb_nd,
client_requests[request_id].retries,
&(client_requests[request_id].error_code),
&(client_requests[request_id].resp_timeout),
&(client_requests[request_id].coms_buf_mutex));
case 3: /* read holding registers */
return read_output_words(client_requests[request_id].slave_id,
client_requests[request_id].address,
client_requests[request_id].count,
client_requests[request_id].coms_buffer,
(int) client_requests[request_id].count,
client_nodes[client_requests[request_id].client_node_id].mb_nd,
client_requests[request_id].retries,
&(client_requests[request_id].error_code),
&(client_requests[request_id].resp_timeout),
&(client_requests[request_id].coms_buf_mutex));
case 4: /* read input registers */
return read_input_words(client_requests[request_id].slave_id,
client_requests[request_id].address,
client_requests[request_id].count,
client_requests[request_id].coms_buffer,
(int) client_requests[request_id].count,
client_nodes[client_requests[request_id].client_node_id].mb_nd,
client_requests[request_id].retries,
&(client_requests[request_id].error_code),
&(client_requests[request_id].resp_timeout),
&(client_requests[request_id].coms_buf_mutex));
case 5: /* write single coil */
return write_output_bit(client_requests[request_id].slave_id,
client_requests[request_id].address,
client_requests[request_id].coms_buffer[0],
client_nodes[client_requests[request_id].client_node_id].mb_nd,
client_requests[request_id].retries,
&(client_requests[request_id].error_code),
&(client_requests[request_id].resp_timeout),
&(client_requests[request_id].coms_buf_mutex));
case 6: /* write single register */
return write_output_word(client_requests[request_id].slave_id,
client_requests[request_id].address,
client_requests[request_id].coms_buffer[0],
client_nodes[client_requests[request_id].client_node_id].mb_nd,
client_requests[request_id].retries,
&(client_requests[request_id].error_code),
&(client_requests[request_id].resp_timeout),
&(client_requests[request_id].coms_buf_mutex));
case 7: break; /* function not yet supported */
case 8: break; /* function not yet supported */
case 9: break; /* function not yet supported */
case 10: break; /* function not yet supported */
case 11: break; /* function not yet supported */
case 12: break; /* function not yet supported */
case 13: break; /* function not yet supported */
case 14: break; /* function not yet supported */
case 15: /* write multiple coils */
return write_output_bits(client_requests[request_id].slave_id,
client_requests[request_id].address,
client_requests[request_id].count,
client_requests[request_id].coms_buffer,
client_nodes[client_requests[request_id].client_node_id].mb_nd,
client_requests[request_id].retries,
&(client_requests[request_id].error_code),
&(client_requests[request_id].resp_timeout),
&(client_requests[request_id].coms_buf_mutex));
case 16: /* write multiple registers */
return write_output_words(client_requests[request_id].slave_id,
client_requests[request_id].address,
client_requests[request_id].count,
client_requests[request_id].coms_buffer,
client_nodes[client_requests[request_id].client_node_id].mb_nd,
client_requests[request_id].retries,
&(client_requests[request_id].error_code),
&(client_requests[request_id].resp_timeout),
&(client_requests[request_id].coms_buf_mutex));
default: break; /* should never occur, if file generation is correct */
}
fprintf(stderr, "Modbus plugin: Modbus function %%d not supported\n", request_id); /* should never occur, if file generation is correct */
return -1;
}
/* pack bits from unpacked_data to packed_data */
static inline int __pack_bits(u16 *unpacked_data, u16 start_addr, u16 bit_count, u8 *packed_data) {
u8 bit;
u16 byte, coils_processed;
if ((0 == bit_count) || (65535-start_addr < bit_count-1))
return -ERR_ILLEGAL_DATA_ADDRESS; /* ERR_ILLEGAL_DATA_ADDRESS defined in mb_util.h */
for( byte = 0, coils_processed = 0; coils_processed < bit_count; byte++) {
packed_data[byte] = 0;
for( bit = 0x01; (bit & 0xFF) && (coils_processed < bit_count); bit <<= 1, coils_processed++ ) {
if(unpacked_data[start_addr + coils_processed])
packed_data[byte] |= bit; /* set bit */
else packed_data[byte] &= ~bit; /* reset bit */
}
}
return 0;
}
/* unpack bits from packed_data to unpacked_data */
static inline int __unpack_bits(u16 *unpacked_data, u16 start_addr, u16 bit_count, u8 *packed_data) {
u8 temp, bit;
u16 byte, coils_processed;
if ((0 == bit_count) || (65535-start_addr < bit_count-1))
return -ERR_ILLEGAL_DATA_ADDRESS; /* ERR_ILLEGAL_DATA_ADDRESS defined in mb_util.h */
for(byte = 0, coils_processed = 0; coils_processed < bit_count; byte++) {
temp = packed_data[byte] ;
for(bit = 0x01; (bit & 0xff) && (coils_processed < bit_count); bit <<= 1, coils_processed++) {
unpacked_data[start_addr + coils_processed] = (temp & bit)?1:0;
}
}
return 0;
}
static int __read_inbits (void *mem_map, u16 start_addr, u16 bit_count, u8 *data_bytes)
{return __pack_bits(((server_mem_t *)mem_map)->ro_bits, start_addr, bit_count, data_bytes);}
static int __read_outbits (void *mem_map, u16 start_addr, u16 bit_count, u8 *data_bytes)
{return __pack_bits(((server_mem_t *)mem_map)->rw_bits, start_addr, bit_count, data_bytes);}
static int __write_outbits (void *mem_map, u16 start_addr, u16 bit_count, u8 *data_bytes)
{return __unpack_bits(((server_mem_t *)mem_map)->rw_bits, start_addr, bit_count, data_bytes); }
static int __read_inwords (void *mem_map, u16 start_addr, u16 word_count, u16 *data_words) {
if ((start_addr + word_count) > MEM_AREA_SIZE)
return -ERR_ILLEGAL_DATA_ADDRESS; /* ERR_ILLEGAL_DATA_ADDRESS defined in mb_util.h */
/* use memcpy() because loop with pointers (u16 *) caused alignment problems */
memcpy(/* dest */ (void *)data_words,
/* src */ (void *)&(((server_mem_t *)mem_map)->ro_words[start_addr]),
/* size */ word_count * 2);
return 0;
}
static int __read_outwords (void *mem_map, u16 start_addr, u16 word_count, u16 *data_words) {
if ((start_addr + word_count) > MEM_AREA_SIZE)
return -ERR_ILLEGAL_DATA_ADDRESS; /* ERR_ILLEGAL_DATA_ADDRESS defined in mb_util.h */
/* use memcpy() because loop with pointers (u16 *) caused alignment problems */
memcpy(/* dest */ (void *)data_words,
/* src */ (void *)&(((server_mem_t *)mem_map)->rw_words[start_addr]),
/* size */ word_count * 2);
return 0;
}
static int __write_outwords(void *mem_map, u16 start_addr, u16 word_count, u16 *data_words) {
if ((start_addr + word_count) > MEM_AREA_SIZE)
return -ERR_ILLEGAL_DATA_ADDRESS; /* ERR_ILLEGAL_DATA_ADDRESS defined in mb_util.h */
/* WARNING: The data returned in the data_words[] array is not guaranteed to be 16 bit aligned.
* It is not therefore safe to cast it to an u16 data type.
* The following code cannot be used. memcpy() is used instead.
*/
/*
for (count = 0; count < word_count ; count++)
((server_mem_t *)mem_map)->rw_words[count + start_addr] = data_words[count];
*/
memcpy(/* dest */ (void *)&(((server_mem_t *)mem_map)->rw_words[start_addr]),
/* src */ (void *)data_words,
/* size */ word_count * 2);
return 0;
}
#include <pthread.h>
static void *__mb_server_thread(void *_server_node) {
server_node_t *server_node = _server_node;
mb_slave_callback_t callbacks = {
&__read_inbits,
&__read_outbits,
&__write_outbits,
&__read_inwords,
&__read_outwords,
&__write_outwords,
(void *)&(server_node->mem_area)
};
// Enable thread cancelation. Enabled is default, but set it anyway to be safe.
pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
// mb_slave_run() should never return!
mb_slave_run(server_node->mb_nd /* nd */, callbacks, server_node->slave_id);
fprintf(stderr, "Modbus plugin: Modbus server for node %%s died unexpectedly!\n", server_node->location); /* should never occur */
return NULL;
}
#define timespec_add(ts, sec, nsec) { \
ts.tv_sec += sec; \
ts.tv_nsec += nsec; \
if (ts.tv_nsec >= 1000000000) { \
ts.tv_sec ++; \
ts.tv_nsec -= 1000000000; \
} \
}
static void *__mb_client_thread(void *_index) {
int client_node_id = (char *)_index - (char *)NULL; // Use pointer arithmetic (more portable than cast)
struct timespec next_cycle;
int period_sec = client_nodes[client_node_id].comm_period / 1000; /* comm_period is in ms */
int period_nsec = (client_nodes[client_node_id].comm_period %%1000)*1000000; /* comm_period is in ms */
// Enable thread cancelation. Enabled is default, but set it anyway to be safe.
pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
// get the current time
clock_gettime(CLOCK_MONOTONIC, &next_cycle);
// loop the communication with the client
while (1) {
/*
struct timespec cur_time;
clock_gettime(CLOCK_MONOTONIC, &cur_time);
fprintf(stderr, "Modbus client thread - new cycle (%%ld:%%ld)!\n", cur_time.tv_sec, cur_time.tv_nsec);
*/
int req;
for (req=0; req < NUMBER_OF_CLIENT_REQTS; req ++){
/*just do the requests belonging to the client */
if (client_requests[req].client_node_id != client_node_id)
continue;
int res_tmp = __execute_mb_request(req);
switch (res_tmp) {
case PORT_FAILURE: {
if (res_tmp != client_nodes[client_node_id].prev_error)
fprintf(stderr, "Modbus plugin: Error connecting Modbus client %%s to remote server.\n", client_nodes[client_node_id].location);
client_nodes[client_node_id].prev_error = res_tmp;
break;
}
case INVALID_FRAME: {
if ((res_tmp != client_requests[req].prev_error) && (0 == client_nodes[client_node_id].prev_error))
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);
client_requests[req].prev_error = res_tmp;
break;
}
case TIMEOUT: {
if ((res_tmp != client_requests[req].prev_error) && (0 == client_nodes[client_node_id].prev_error))
fprintf(stderr, "Modbus plugin: Modbus client request configured at location %%s timed out waiting for reply from server.\n", client_requests[req].location);
client_requests[req].prev_error = res_tmp;
break;
}
case MODBUS_ERROR: {
if (client_requests[req].prev_error != client_requests[req].error_code) {
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].error_code);
if (client_requests[req].error_code <= MAX_MODBUS_ERROR_CODE ) {
fprintf(stderr, "(%%s)", modbus_error_messages[client_requests[req].error_code]);
fprintf(stderr, ".\n");
}
}
client_requests[req].prev_error = client_requests[req].error_code;
break;
}
default: {
if ((res_tmp >= 0) && (client_nodes[client_node_id].prev_error != 0)) {
fprintf(stderr, "Modbus plugin: Modbus client %%s has reconnected to server/slave.\n", client_nodes[client_node_id].location);
}
if ((res_tmp >= 0) && (client_requests[req] .prev_error != 0)) {
fprintf(stderr, "Modbus plugin: Modbus client request configured at location %%s has succesfully resumed comunication.\n", client_requests[req].location);
}
client_nodes[client_node_id].prev_error = 0;
client_requests[req] .prev_error = 0;
break;
}
}
}
// Determine absolute time instant for starting the next cycle
struct timespec prev_cycle, now;
prev_cycle = next_cycle;
timespec_add(next_cycle, period_sec, period_nsec);
/* NOTE A:
* When we have difficulty communicating with remote client and/or server, then the communications get delayed and we will
* fall behind in the period. This means that when communication is re-established we may end up running this loop continuously
* for some time until we catch up.
* This is undesirable, so we detect it by making sure the next_cycle will start in the future.
* When this happens we will switch from a purely periodic task _activation_ sequence, to a fixed task suspension interval.
*
* NOTE B:
* It probably does not make sense to check for overflow of timer - so we don't do it for now!
* Even in 32 bit systems this will take at least 68 years since the computer booted
* (remember, we are using CLOCK_MONOTONIC, which should start counting from 0
* every time the system boots). On 64 bit systems, it will take over
* 10^11 years to overflow.
*/
clock_gettime(CLOCK_MONOTONIC, &now);
if ( ((now.tv_sec > next_cycle.tv_sec) || ((now.tv_sec == next_cycle.tv_sec) && (now.tv_nsec > next_cycle.tv_nsec)))
/* We are falling behind. See NOTE A above */
|| (next_cycle.tv_sec < prev_cycle.tv_sec)
/* Timer overflow. See NOTE B above */
) {
next_cycle = now;
timespec_add(next_cycle, period_sec, period_nsec);
}
clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME, &next_cycle, NULL);
}
// humour the compiler.
return NULL;
}
int __cleanup_%(locstr)s ();
int __init_%(locstr)s (int argc, char **argv){
int index;
for (index=0; index < NUMBER_OF_CLIENT_NODES;index++)
client_nodes[index].mb_nd = -1;
for (index=0; index < NUMBER_OF_SERVER_NODES;index++)
// mb_nd with negative numbers indicate how far it has been initialised (or not)
// -2 --> no modbus node created; no thread created
// -1 --> modbus node created!; no thread created
// >=0 --> modbus node created!; thread created!
server_nodes[index].mb_nd = -2;
/* modbus library init */
/* Note that TOTAL_xxxNODE_COUNT are the nodes required by _ALL_ the instances of the modbus
* extension currently in the user's project. This file (MB_xx.c) is handling only one instance,
* but must initialize the library for all instances. Only the first call to mb_slave_and_master_init()
* will result in memory being allocated. All subsequent calls (by other MB_xx,c files) will be ignored
* by the mb_slave_and_master_init() funtion, as long as they are called with the same arguments.
*/
if (mb_slave_and_master_init(TOTAL_TCPNODE_COUNT, TOTAL_RTUNODE_COUNT, TOTAL_ASCNODE_COUNT) <0) {
fprintf(stderr, "Modbus plugin: Error starting modbus library\n");
// return imediately. Do NOT goto error_exit, as we did not get to
// start the modbus library!
return -1;
}
/* init the mutex for each client request */
/* Must be done _before_ launching the client threads!! */
for (index=0; index < NUMBER_OF_CLIENT_REQTS; index ++){
if (pthread_mutex_init(&(client_requests[index].coms_buf_mutex), NULL)) {
fprintf(stderr, "Modbus plugin: Error initializing request for modbus client node %%s\n", client_nodes[client_requests[index].client_node_id].location);
goto error_exit;
}
}
/* init each client connection to remote modbus server, and launch thread */
/* NOTE: All client_nodes[].init_state are initialised to 0 in the code
* generated by the modbus plugin
*/
for (index=0; index < NUMBER_OF_CLIENT_NODES;index++){
/* establish client connection */
client_nodes[index].mb_nd = mb_master_connect (client_nodes[index].node_address);
if (client_nodes[index].mb_nd < 0){
fprintf(stderr, "Modbus plugin: Error creating modbus client node %%s\n", client_nodes[index].location);
goto error_exit;
}
client_nodes[index].init_state = 1; // we have created the node
/* launch a thread to handle this client node */
{
int res = 0;
pthread_attr_t attr;
res |= pthread_attr_init(&attr);
res |= pthread_create(&(client_nodes[index].thread_id), &attr, &__mb_client_thread, (void *)((char *)NULL + index));
if (res != 0) {
fprintf(stderr, "Modbus plugin: Error starting modbus client thread for node %%s\n", client_nodes[index].location);
goto error_exit;
}
}
client_nodes[index].init_state = 2; // we have created the node and a thread
}
/* init each local server */
/* NOTE: All server_nodes[].init_state are initialised to 0 in the code
* generated by the modbus plugin
*/
for (index=0; index < NUMBER_OF_SERVER_NODES;index++){
/* create the modbus server */
server_nodes[index].mb_nd = mb_slave_new (server_nodes[index].node_address);
if (server_nodes[index].mb_nd < 0){
fprintf(stderr, "Modbus plugin: Error creating modbus server node %%s\n", server_nodes[index].location);
goto error_exit;
}
server_nodes[index].init_state = 1; // we have created the node
/* launch a thread to handle this server node */
{
int res = 0;
pthread_attr_t attr;
res |= pthread_attr_init(&attr);
res |= pthread_create(&(server_nodes[index].thread_id), &attr, &__mb_server_thread, (void *)&(server_nodes[index]));
if (res != 0) {
fprintf(stderr, "Modbus plugin: Error starting modbus server thread for node %%s\n", server_nodes[index].location);
goto error_exit;
}
}
server_nodes[index].init_state = 2; // we have created the node and thread
}
return 0;
error_exit:
__cleanup_%(locstr)s ();
return -1;
}
void __publish_%(locstr)s (){
int index;
for (index=0; index < NUMBER_OF_CLIENT_REQTS; index ++){
/*just do the output requests */
if (client_requests[index].req_type == req_output){
if(pthread_mutex_trylock(&(client_requests[index].coms_buf_mutex)) == 0){
// copy from plcv_buffer to coms_buffer
memcpy((void *)client_requests[index].coms_buffer /* destination */,
(void *)client_requests[index].plcv_buffer /* source */,
REQ_BUF_SIZE * sizeof(u16) /* size in bytes */);
pthread_mutex_unlock(&(client_requests[index].coms_buf_mutex));
}
}
}
}
void __retrieve_%(locstr)s (){
int index;
for (index=0; index < NUMBER_OF_CLIENT_REQTS; index ++){
/*just do the input requests */
if (client_requests[index].req_type == req_input){
if(pthread_mutex_trylock(&(client_requests[index].coms_buf_mutex)) == 0){
// copy from coms_buffer to plcv_buffer
memcpy((void *)client_requests[index].plcv_buffer /* destination */,
(void *)client_requests[index].coms_buffer /* source */,
REQ_BUF_SIZE * sizeof(u16) /* size in bytes */);
pthread_mutex_unlock(&(client_requests[index].coms_buf_mutex));
}
}
}
}
int __cleanup_%(locstr)s (){
int index, close;
int res = 0;
/* kill thread and close connections of each modbus client node */
for (index=0; index < NUMBER_OF_CLIENT_NODES; index++) {
close = 0;
if (client_nodes[index].init_state >= 2) {
// thread was launched, so we try to cancel it!
close = pthread_cancel(client_nodes[index].thread_id);
close |= pthread_join (client_nodes[index].thread_id, NULL);
if (close < 0)
fprintf(stderr, "Modbus plugin: Error closing thread for modbus client %%s\n", client_nodes[index].location);
}
res |= close;
close = 0;
if (client_nodes[index].init_state >= 1) {
// modbus client node was created, so we try to close it!
close = mb_master_close (client_nodes[index].mb_nd);
if (close < 0){
fprintf(stderr, "Modbus plugin: Error closing modbus client node %%s\n", client_nodes[index].location);
// We try to shut down as much as possible, so we do not return noW!
}
client_nodes[index].mb_nd = -1;
}
res |= close;
client_nodes[index].init_state = 0;
}
/* kill thread and close connections of each modbus server node */
for (index=0; index < NUMBER_OF_SERVER_NODES; index++) {
close = 0;
if (server_nodes[index].init_state >= 2) {
// thread was launched, so we try to cancel it!
close = pthread_cancel(server_nodes[index].thread_id);
close |= pthread_join (server_nodes[index].thread_id, NULL);
if (close < 0)
fprintf(stderr, "Modbus plugin: Error closing thread for modbus server %%s\n", server_nodes[index].location);
}
res |= close;
close = 0;
if (server_nodes[index].init_state >= 1) {
// modbus server node was created, so we try to close it!
close = mb_slave_close (server_nodes[index].mb_nd);
if (close < 0) {
fprintf(stderr, "Modbus plugin: Error closing node for modbus server %%s (%%d)\n", server_nodes[index].location, server_nodes[index].mb_nd);
// We try to shut down as much as possible, so we do not return noW!
}
server_nodes[index].mb_nd = -1;
}
res |= close;
server_nodes[index].init_state = 0;
}
/* destroy the mutex of each client request */
for (index=0; index < NUMBER_OF_CLIENT_REQTS; index ++) {
if (pthread_mutex_destroy(&(client_requests[index].coms_buf_mutex))) {
fprintf(stderr, "Modbus plugin: Error destroying request for modbus client node %%s\n", client_nodes[client_requests[index].client_node_id].location);
// We try to shut down as much as possible, so we do not return noW!
res |= -1;
}
}
/* modbus library close */
//fprintf(stderr, "Shutting down modbus library...\n");
if (mb_slave_and_master_done()<0) {
fprintf(stderr, "Modbus plugin: Error shutting down modbus library\n");
res |= -1;
}
return res;
}