Python Safe Globals now have more reliable triggering of OnChange call. Added "Onchange" object to accessible runtime variables that let user python code see count of changes and first and last values.
/* 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 <errno.h>
#include <time.h>
#include <signal.h>
#include <unistd.h> /* required for pause() */
#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)
// Enable thread cancelation. Enabled is default, but set it anyway to be safe.
pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
/* loop the communication with the client
*
* When the client thread has difficulty communicating with remote client and/or server (network issues, for example),
* then the communications get delayed and we will fall behind in the period.
*
* This is OK. Note that if the condition variable were to be signaled multiple times while the client thread is inside the same
* Modbus transaction, then all those signals would be ignored.
* However, and since we keep the mutex locked during the communication cycle, it is not possible to signal the condition variable
* during that time (it is only possible while the thread is blocked during the call to pthread_cond_wait().
*
* This means that when network issues eventually get resolved, we will NOT have a bunch of delayed activations to handle
* in quick succession (which would goble up CPU time).
*
* Notice that the above property is valid whether the communication cycle is run with the mutex locked, or unlocked.
* Since it makes it easier to implement the correct semantics for the other activation methods if the communication cycle
* is run with the mutex locked, then that is what we do.
*
* Note that during all the communication cycle we will keep locked the mutex
* (i.e. the mutex used together with the condition variable that will activate a new communication cycle)
*
* Note that we never get to explicitly unlock this mutex. It will only be unlocked by the pthread_cond_wait()
* call at the end of the cycle.
*/
pthread_mutex_lock(&(client_nodes[client_node_id].mutex));
while (1) {
/*
struct timespec cur_time;
clock_gettime(CLOCK_MONOTONIC, &cur_time);
fprintf(stderr, "Modbus client thread (%%d) - new cycle (%%ld:%%ld)!\n", client_node_id, 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;
/* only do the request if:
* - this request was explictly asked to be executed by the client program
* OR
* - the client thread was activated periodically
* (in which case we execute all the requests belonging to the client node)
*/
if ((client_requests[req].flag_exec_req == 0) && (client_nodes[client_requests[req].client_node_id].periodic_act == 0))
continue;
/*
fprintf(stderr, "Modbus client thread (%%d): RUNNING Modbus request %%d (periodic = %%d flag_exec_req = %%d)\n",
client_node_id, req, client_nodes[client_requests[req].client_node_id].periodic_act, client_requests[req].flag_exec_req );
*/
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;
}
}
/* We have just finished excuting a client transcation request.
* If the current cycle was activated by user request we reset the flag used to ask to run it
*/
if (0 != client_requests[req].flag_exec_req) {
client_requests[req].flag_exec_req = 0;
client_requests[req].flag_exec_started = 0;
}
//fprintf(stderr, "Modbus plugin: RUNNING<---> of Modbus request %%d (periodic = %%d flag_exec_req = %%d)\n",
// req, client_nodes[client_requests[req].client_node_id].periodic_act, client_requests[req].flag_exec_req );
}
// Wait for signal (from timer or explicit request from user program) before starting the next cycle
{
// No need to lock the mutex. Is is already locked just before the while(1) loop.
// Read the comment there to understand why.
// pthread_mutex_lock(&(client_nodes[client_node_id].mutex));
/* the client thread has just finished a cycle, so all the flags used to signal an activation
* and specify the activation source (periodic, user request, ...)
* get reset here, before waiting for a new activation.
*/
client_nodes[client_node_id].periodic_act = 0;
client_nodes[client_node_id].execute_req = 0;
while (client_nodes[client_node_id].execute_req == 0)
pthread_cond_wait(&(client_nodes[client_node_id].condv),
&(client_nodes[client_node_id].mutex));
// We run the communication cycle with the mutex locked.
// Read the comment just above the while(1) to understand why.
// pthread_mutex_unlock(&(client_nodes[client_node_id].mutex));
}
}
// humour the compiler.
return NULL;
}
/* Thread that simply implements a periodic 'timer',
* i.e. periodically sends signal to the thread running __mb_client_thread()
*
* Note that we do not use a posix timer (timer_create() ) because there doesn't seem to be a way
* of having the timer notify the thread that is portable across Xenomai and POSIX.
* - SIGEV_THREAD : not supported by Xenomai
* - SIGEV_THREAD_ID : Linux specific (i.e. non POSIX)
* Even so, I did not get it to work under Linux (issues with the header files)
* - SIGEV_SIGNAL : Will not work, as signal is sent to random thread in process!
*/
static void *__mb_client_timer_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);
if (client_nodes[client_node_id].comm_period <= 0) {
// No periodic activation required => nothing to do!
while (1) pause(); // wait to be canceled when program terminates (shutdown() is called)
return NULL; // not really necessary, just makes it easier to understand the code.
}
// get the current time
clock_gettime(CLOCK_MONOTONIC, &next_cycle);
while(1) {
// 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:
* It is probably un-necessary to check for overflow of timer!
* 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 (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);
}
while (0 != clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME, &next_cycle, NULL));
/* signal the client node's condition variable on which the client node's thread should be waiting... */
/* Since the communication cycle is run with the mutex locked, we use trylock() instead of lock() */
if (pthread_mutex_trylock (&(client_nodes[client_node_id].mutex)) == 0) {
client_nodes[client_node_id].execute_req = 1; // tell the thread to execute
client_nodes[client_node_id].periodic_act = 1; // tell the thread the activation was done by periodic timer
pthread_cond_signal (&(client_nodes[client_node_id].condv));
pthread_mutex_unlock(&(client_nodes[client_node_id].mutex));
} else {
/* We never get to signal the thread for activation. But that is OK.
* If it still in the communication cycle (during which the mutex is kept locked)
* then that means that the communication cycle is falling behing in the periodic
* communication cycle, and we therefore need to skip a period.
*/
}
}
return NULL; // humour the compiler -> will never be executed!
}
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;
/* see comment in mb_runtime.h to understad why we need to initialize these entries */
switch (client_nodes[index].node_address.naf) {
case naf_tcp:
client_nodes[index].node_address.addr.tcp.host = client_nodes[index].str1;
client_nodes[index].node_address.addr.tcp.service = client_nodes[index].str2;
break;
case naf_rtu:
client_nodes[index].node_address.addr.rtu.device = client_nodes[index].str1;
break;
}
}
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;
/* see comment in mb_runtime.h to understad why we need to initialize these entries */
switch (server_nodes[index].node_address.naf) {
case naf_tcp:
server_nodes[index].node_address.addr.tcp.host = server_nodes[index].str1;
server_nodes[index].node_address.addr.tcp.service = server_nodes[index].str2;
break;
case naf_rtu:
server_nodes[index].node_address.addr.rtu.device = server_nodes[index].str1;
break;
}
}
/* 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 each client request */
/* Must be done _before_ launching the client threads!! */
for (index=0; index < NUMBER_OF_CLIENT_REQTS; index ++){
/* make sure flags connected to user program MB transaction start request are all reset */
client_requests[index].flag_exec_req = 0;
client_requests[index].flag_exec_started = 0;
/* init the mutex for each client request */
/* Must be done _before_ launching the client threads!! */
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
/* initialize the mutex variable that will be used by the thread handling the client node */
bzero(&(client_nodes[index].mutex), sizeof(pthread_mutex_t));
if (pthread_mutex_init(&(client_nodes[index].mutex), NULL) < 0) {
fprintf(stderr, "Modbus plugin: Error creating mutex for modbus client node %%s\n", client_nodes[index].location);
goto error_exit;
}
client_nodes[index].init_state = 2; // we have created the mutex
/* initialize the condition variable that will be used by the thread handling the client node */
bzero(&(client_nodes[index].condv), sizeof(pthread_cond_t));
if (pthread_cond_init(&(client_nodes[index].condv), NULL) < 0) {
fprintf(stderr, "Modbus plugin: Error creating condition variable for modbus client node %%s\n", client_nodes[index].location);
goto error_exit;
}
client_nodes[index].execute_req = 0; //variable associated with condition variable
client_nodes[index].init_state = 3; // we have created the condition variable
/* launch a thread to handle this client node timer */
{
int res = 0;
pthread_attr_t attr;
res |= pthread_attr_init(&attr);
res |= pthread_create(&(client_nodes[index].timer_thread_id), &attr, &__mb_client_timer_thread, (void *)((char *)NULL + index));
if (res != 0) {
fprintf(stderr, "Modbus plugin: Error starting timer thread for modbus client node %%s\n", client_nodes[index].location);
goto error_exit;
}
}
client_nodes[index].init_state = 4; // we have created the timer
/* 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 thread for modbus client node %%s\n", client_nodes[index].location);
goto error_exit;
}
}
client_nodes[index].init_state = 5; // we have created the 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 ++){
/* synchronize the PLC and MB buffers only for the output requests */
if (client_requests[index].req_type == req_output){
// lock the mutex brefore copying the data
if(pthread_mutex_trylock(&(client_requests[index].coms_buf_mutex)) == 0){
// Check if user configured this MB request to be activated whenever the data to be written changes
if (client_requests[index].write_on_change) {
// Let's check if the data did change...
// compare the data in plcv_buffer to coms_buffer
int res;
res = memcmp((void *)client_requests[index].coms_buffer /* buf 1 */,
(void *)client_requests[index].plcv_buffer /* buf 2*/,
REQ_BUF_SIZE * sizeof(u16) /* size in bytes */);
// if data changed, activate execution request
if (0 != res)
client_requests[index].flag_exec_req = 1;
}
// 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));
}
}
/* if the user program set the execution request flag, then activate the thread
* that handles this Modbus client transaction so it gets a chance to be executed
* (but don't activate the thread if it has already been activated!)
*
* NOTE that we do this, for both the IN and OUT mapped location, under this
* __publish_() function. The scan cycle of the PLC works as follows:
* - call __retrieve_()
* - execute user programs
* - call __publish_()
* - insert <delay> until time to start next periodic/cyclic scan cycle
*
* In an attempt to be able to run the MB transactions during the <delay>
* interval in which not much is going on, we handle the user program
* requests to execute a specific MB transaction in this __publish_()
* function.
*/
if ((client_requests[index].flag_exec_req != 0) && (0 == client_requests[index].flag_exec_started)) {
int client_node_id = client_requests[index].client_node_id;
/* We TRY to signal the client thread.
* We do this because this function can be called at the end of the PLC scan cycle
* and we don't want it to block at that time.
*/
if (pthread_mutex_trylock(&(client_nodes[client_node_id].mutex)) == 0) {
client_nodes[client_node_id].execute_req = 1; // tell the thread to execute
pthread_cond_signal (&(client_nodes[client_node_id].condv));
pthread_mutex_unlock(&(client_nodes[client_node_id].mutex));
/* - upon success, set flag_exec_started
* - both flags (flag_exec_req and flag_exec_started) will be reset
* once the transaction has completed.
*/
client_requests[index].flag_exec_started = 1;
} else {
/* The mutex is locked => the client thread is currently executing MB transactions.
* We will try to activate it in the next PLC cycle...
* For now, do nothing.
*/
}
}
}
}
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 >= 5) {
// 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 node %%s\n", client_nodes[index].location);
}
res |= close;
close = 0;
if (client_nodes[index].init_state >= 4) {
// timer thread was launched, so we try to cancel it!
close = pthread_cancel(client_nodes[index].timer_thread_id);
close |= pthread_join (client_nodes[index].timer_thread_id, NULL);
if (close < 0)
fprintf(stderr, "Modbus plugin: Error closing timer thread for modbus client node %%s\n", client_nodes[index].location);
}
res |= close;
close = 0;
if (client_nodes[index].init_state >= 3) {
// condition variable was created, so we try to destroy it!
close = pthread_cond_destroy(&(client_nodes[index].condv));
if (close < 0)
fprintf(stderr, "Modbus plugin: Error destroying condition variable for modbus client node %%s\n", client_nodes[index].location);
}
res |= close;
close = 0;
if (client_nodes[index].init_state >= 2) {
// mutex was created, so we try to destroy it!
close = pthread_mutex_destroy(&(client_nodes[index].mutex));
if (close < 0)
fprintf(stderr, "Modbus plugin: Error destroying mutex for modbus client node %%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;
}
//fprintf(stderr, "Modbus plugin: __cleanup_%%s() 5 close=%%d res=%%d\n", client_nodes[index].location, close, res);
/* 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;
}
/**********************************************/
/** Functions for Beremiz web interface. **/
/**********************************************/
/*
* Beremiz has a program to run on the PLC (Beremiz_service.py)
* to handle downloading of compiled programs, start/stop of PLC, etc.
* (see runtime/PLCObject.py for start/stop, loading, ...)
*
* This service also includes a web server to access PLC state (start/stop)
* and to change some basic confiuration parameters.
* (see runtime/NevowServer.py for the web server)
*
* The web server allows for extensions, where additional configuration
* parameters may be changed on the running/downloaded PLC.
* Modbus plugin also comes with an extension to the web server, through
* which the basic Modbus plugin configuration parameters may be changed
*
* These parameters are changed _after_ the code (.so file) is loaded into
* memmory. These changes may be applied before (or after) the code starts
* running (i.e. before or after __init_() ets called)!
*
* The following functions are never called from other C code. They are
* called instead from the python code in runtime/Modbus_config.py, that
* implements the web server extension for configuring Modbus parameters.
*/
/* The number of Cient nodes (i.e. the number of entries in the client_nodes array)
* The number of Server nodes (i.e. the numb. of entries in the server_nodes array)
*
* These variables are also used by the Modbus web config code to determine
* whether the current loaded PLC includes the Modbus plugin
* (so it should make the Modbus parameter web interface visible to the user).
*/
const int __modbus_plugin_client_node_count = NUMBER_OF_CLIENT_NODES;
const int __modbus_plugin_server_node_count = NUMBER_OF_SERVER_NODES;
const int __modbus_plugin_param_string_size = MODBUS_PARAM_STRING_SIZE;
/* NOTE: We could have the python code in runtime/Modbus_config.py
* directly access the server_node_t and client_node_t structures,
* however this would create a tight coupling between these two
* disjoint pieces of code.
* Any change to the server_node_t or client_node_t structures would
* require the python code to be changed accordingly. I have therefore
* opted to create get/set functions, one for each parameter.
*
* We also convert the enumerated constants naf_ascii, etc...
* (from node_addr_family_t in modbus/mb_addr.h)
* into strings so as to decouple the python code that will be calling
* these functions from the Modbus library code definitions.
*/
const char *addr_type_str[] = {
[naf_ascii] = "ascii",
[naf_rtu ] = "rtu",
[naf_tcp ] = "tcp"
};
#define __safe_strcnpy(str_dest, str_orig, max_size) { \
strncpy(str_dest, str_orig, max_size); \
str_dest[max_size - 1] = '\0'; \
}
/* NOTE: The host, port and device parameters are strings that may be changed
* (by calling the following functions) after loading the compiled code
* (.so file) into memory, but before the code starts running
* (i.e. before __init_() gets called).
* This means that the host, port and device parameters may be changed
* _before_ they get mapped onto the str1 and str2 variables by __init_(),
* which is why the following functions must access the str1 and str2
* parameters directly.
*/
const char * __modbus_get_ClientNode_config_name(int nodeid) {return client_nodes[nodeid].config_name; }
const char * __modbus_get_ClientNode_host (int nodeid) {return client_nodes[nodeid].str1; }
const char * __modbus_get_ClientNode_port (int nodeid) {return client_nodes[nodeid].str2; }
const char * __modbus_get_ClientNode_device (int nodeid) {return client_nodes[nodeid].str1; }
int __modbus_get_ClientNode_baud (int nodeid) {return client_nodes[nodeid].node_address.addr.rtu.baud; }
int __modbus_get_ClientNode_parity (int nodeid) {return client_nodes[nodeid].node_address.addr.rtu.parity; }
int __modbus_get_ClientNode_stop_bits (int nodeid) {return client_nodes[nodeid].node_address.addr.rtu.stop_bits;}
u64 __modbus_get_ClientNode_comm_period(int nodeid) {return client_nodes[nodeid].comm_period; }
const char * __modbus_get_ClientNode_addr_type (int nodeid) {return addr_type_str[client_nodes[nodeid].node_address.naf];}
const char * __modbus_get_ServerNode_config_name(int nodeid) {return server_nodes[nodeid].config_name; }
const char * __modbus_get_ServerNode_host (int nodeid) {char*x=server_nodes[nodeid].str1; return (x[0]=='\0'?"#ANY#":x); }
const char * __modbus_get_ServerNode_port (int nodeid) {return server_nodes[nodeid].str2; }
const char * __modbus_get_ServerNode_device (int nodeid) {return server_nodes[nodeid].str1; }
int __modbus_get_ServerNode_baud (int nodeid) {return server_nodes[nodeid].node_address.addr.rtu.baud; }
int __modbus_get_ServerNode_parity (int nodeid) {return server_nodes[nodeid].node_address.addr.rtu.parity; }
int __modbus_get_ServerNode_stop_bits (int nodeid) {return server_nodes[nodeid].node_address.addr.rtu.stop_bits;}
u8 __modbus_get_ServerNode_slave_id (int nodeid) {return server_nodes[nodeid].slave_id; }
const char * __modbus_get_ServerNode_addr_type (int nodeid) {return addr_type_str[server_nodes[nodeid].node_address.naf];}
void __modbus_set_ClientNode_host (int nodeid, const char * value) {__safe_strcnpy(client_nodes[nodeid].str1, value, MODBUS_PARAM_STRING_SIZE);}
void __modbus_set_ClientNode_port (int nodeid, const char * value) {__safe_strcnpy(client_nodes[nodeid].str2, value, MODBUS_PARAM_STRING_SIZE);}
void __modbus_set_ClientNode_device (int nodeid, const char * value) {__safe_strcnpy(client_nodes[nodeid].str1, value, MODBUS_PARAM_STRING_SIZE);}
void __modbus_set_ClientNode_baud (int nodeid, int value) {client_nodes[nodeid].node_address.addr.rtu.baud = value;}
void __modbus_set_ClientNode_parity (int nodeid, int value) {client_nodes[nodeid].node_address.addr.rtu.parity = value;}
void __modbus_set_ClientNode_stop_bits (int nodeid, int value) {client_nodes[nodeid].node_address.addr.rtu.stop_bits = value;}
void __modbus_set_ClientNode_comm_period(int nodeid, u64 value) {client_nodes[nodeid].comm_period = value;}
void __modbus_set_ServerNode_host (int nodeid, const char * value) {if (strcmp(value,"#ANY#")==0) value = "";
__safe_strcnpy(server_nodes[nodeid].str1, value, MODBUS_PARAM_STRING_SIZE);}
void __modbus_set_ServerNode_port (int nodeid, const char * value) {__safe_strcnpy(server_nodes[nodeid].str2, value, MODBUS_PARAM_STRING_SIZE);}
void __modbus_set_ServerNode_device (int nodeid, const char * value) {__safe_strcnpy(server_nodes[nodeid].str1, value, MODBUS_PARAM_STRING_SIZE);}
void __modbus_set_ServerNode_baud (int nodeid, int value) {server_nodes[nodeid].node_address.addr.rtu.baud = value;}
void __modbus_set_ServerNode_parity (int nodeid, int value) {server_nodes[nodeid].node_address.addr.rtu.parity = value;}
void __modbus_set_ServerNode_stop_bits (int nodeid, int value) {server_nodes[nodeid].node_address.addr.rtu.stop_bits = value;}
void __modbus_set_ServerNode_slave_id (int nodeid, u8 value) {server_nodes[nodeid].slave_id = value;}