Fix #463299 - New functions to get/set timeouts of begin and end of trame

Original patch by Sisyph (eric-paul).

NEWS

@@ -4,10 +4,12 @@ libmodbus 2.1.1 (2010-XX-XX)
 - Remove the internal function set_message_length_tcp
 - Restore slave ID (server ID) argument in functions
 - Error conventions of POSIX systems and error recover
-- Versioning infrastructure.
+- Versioning infrastructure
   Inspired by the Clutter project and the work done by Florian Forster.
 - Fix the broadcast constant (255 -> 0)
-  Reported by David Olivari
+  Reported by David Olivari.
+- Fix #463299 - New functions to define the timeouts of begin and end of trame
+  Original patch by Sisyph (eric-paul).
 
 libmodbus 2.1.0 (2010-03-24)
 ============================

src/modbus.c

@@ -615,8 +615,8 @@ static int receive_msg(modbus_param_t *mb_param,
                 state = FUNCTION;
                 msg_length_computed = TAB_HEADER_LENGTH[mb_param->type_com] + 1;
         } else {
-                tv.tv_sec = 0;
-                tv.tv_usec = TIME_OUT_BEGIN_OF_TRAME;
+                tv.tv_sec = mb_param->timeout_begin.tv_sec;
+                tv.tv_usec = mb_param->timeout_begin.tv_usec;
                 state = COMPLETE;
         }
 
@@ -697,8 +697,8 @@ static int receive_msg(modbus_param_t *mb_param,
                 if (length_to_read > 0) {
                         /* If no character at the buffer wait
                            TIME_OUT_END_OF_TRAME before to generate an error. */
-                        tv.tv_sec = 0;
-                        tv.tv_usec = TIME_OUT_END_OF_TRAME;
+                        tv.tv_sec = mb_param->timeout_end.tv_sec;
+                        tv.tv_usec = mb_param->timeout_end.tv_usec;
 
                         WAIT_DATA();
                 } else {
@@ -1466,6 +1466,15 @@ int report_slave_id(modbus_param_t *mb_param, int slave, uint8_t *data_dest)
         return rc;
 }
 
+void init_common(modbus_param_t *mb_param)
+{
+      mb_param->timeout_begin.tv_sec = 0;
+      mb_param->timeout_begin.tv_usec = TIME_OUT_BEGIN_OF_TRAME;
+
+      mb_param->timeout_end.tv_sec = 0;
+      mb_param->timeout_end.tv_usec = TIME_OUT_END_OF_TRAME;
+}
+
 /* Initializes the modbus_param_t structure for RTU
    - device: "/dev/ttyS0"
    - baud:   9600, 19200, 57600, 115200, etc
@@ -1488,6 +1497,8 @@ void modbus_init_rtu(modbus_param_t *mb_param, const char *device,
         mb_param->type_com = RTU;
         mb_param->error_recovery = FALSE;
         mb_param->slave = slave;
+
+        init_common(mb_param);
 }
 
 /* Initializes the modbus_param_t structure for TCP.
@@ -1507,6 +1518,8 @@ void modbus_init_tcp(modbus_param_t *mb_param, const char *ip, int port, int sla
         mb_param->type_com = TCP;
         mb_param->error_recovery = FALSE;
         mb_param->slave = slave;
+
+        init_common(mb_param);
 }
 
 /* Define the slave number */
@@ -1540,6 +1553,30 @@ int modbus_set_error_recovery(modbus_param_t *mb_param, int enabled)
         return 0;
 }
 
+/* Get the timeout of begin of trame */
+void modbus_get_timeout_begin(modbus_param_t *mb_param, struct timeval *timeout)
+{
+        *timeout = mb_param->timeout_begin;
+}
+
+/* Set timeout when waiting the beginning of a trame */
+void modbus_set_timeout_begin(modbus_param_t *mb_param, const struct timeval *timeout)
+{
+        mb_param->timeout_begin = *timeout;
+}
+
+/* Get the timeout of end of trame */
+void modbus_get_timeout_end(modbus_param_t *mb_param, struct timeval *timeout)
+{
+        *timeout = mb_param->timeout_end;
+}
+
+/* Set timeout when waiting the end of a trame */
+void modbus_set_timeout_end(modbus_param_t *mb_param, const struct timeval *timeout)
+{
+        mb_param->timeout_end = *timeout;
+}
+
 /* Sets up a serial port for RTU communications */
 static int modbus_connect_rtu(modbus_param_t *mb_param)
 {

src/modbus.h.in

@@ -234,6 +234,8 @@ typedef struct {
         char ip[16];
         /* Save old termios settings */
         struct termios old_tios;
+        struct timeval timeout_begin;
+        struct timeval timeout_end;
 } modbus_param_t;
 
 typedef struct {
@@ -255,6 +257,12 @@ void modbus_init_tcp(modbus_param_t *mb_param, const char *ip_address, int port,
 void modbus_set_slave(modbus_param_t *mb_param, int slave);
 int modbus_set_error_recovery(modbus_param_t *mb_param, int enabled);
 
+void modbus_get_timeout_begin(modbus_param_t *mb_param, struct timeval *timeout);
+void modbus_set_timeout_begin(modbus_param_t *mb_param, const struct timeval *timeout);
+
+void modbus_get_timeout_end(modbus_param_t *mb_param, struct timeval *timeout);
+void modbus_set_timeout_end(modbus_param_t *mb_param, const struct timeval *timeout);
+
 int modbus_connect(modbus_param_t *mb_param);
 void modbus_close(modbus_param_t *mb_param);
 

tests/unit-test-master.c

@@ -36,6 +36,8 @@ int main(void)
         int nb_points;
         int rc;
         float real;
+        struct timeval timeout_begin_old;
+        struct timeval timeout_begin_new;
 
         /* RTU parity : none, even, odd */
         /*
@@ -468,10 +470,33 @@ int main(void)
         if (rc == UT_HOLDING_REGISTERS_NB_POINTS) {
                 printf("OK\n");
         } else {
+                printf("FAILED\n");
                 goto close;
+        }
+
+        /* Save original timeout */
+        modbus_get_timeout_begin(&mb_param, &timeout_begin_old);
+
+        /* Define a new and too short timeout */
+        timeout_begin_new.tv_sec = 0;
+        timeout_begin_new.tv_usec = 0;
+        modbus_set_timeout_begin(&mb_param, &timeout_begin_new);
+
+        rc = read_holding_registers(&mb_param, SERVER_ID,
+                                    UT_HOLDING_REGISTERS_ADDRESS,
+                                    UT_HOLDING_REGISTERS_NB_POINTS,
+                                    tab_rp_registers);
+        printf("3/3 Too short timeout: ");
+        if (rc == -1 && errno == ETIMEDOUT) {
+                printf("OK\n");
+        } else {
                 printf("FAILED\n");
+                goto close;
         }
 
+        /* Restore original timeout */
+        modbus_set_timeout_begin(&mb_param, &timeout_begin_old);
+
         /** BAD RESPONSE **/
         printf("\nTEST BAD RESPONSE ERROR:\n");