mbus-serial-scan: Make timeout adjustable

This reverts commit a572c0f7429303c3b5974df9cb487911a07d986b.

bin/mbus-serial-scan.c

@@ -11,6 +11,7 @@
 #include <string.h>
 
 #include <stdio.h>
+#include <unistd.h>
 #include <mbus/mbus.h>
 
 static int debug = 0;
@@ -54,60 +55,43 @@ main(int argc, char **argv)
 {
     mbus_handle *handle;
     char *device;
-    int address, retries = 0;
+    int address, retries = 0, timeout = 0;
     long baudrate = 9600;
-    int ret;
+    int opt, ret;
 
-    if (argc == 2)
+    while ((opt = getopt(argc, argv, "db:r:t:")) != -1)
     {
-        device = argv[1];
+        switch (opt)
+        {
+            case 'd':
+                debug = 1;
+                break;
+            case 'b':
+                baudrate = atol(optarg);
+                break;
+            case 'r':
+                retries = atoi(optarg);
+                break;
+            case 't':
+                timeout = atoi(optarg);
+                break;
+            default:
+                fprintf(stderr,"usage: %s [-d] [-b BAUDRATE] [-r RETRIES] [-t TIMEOUT] device\n",
+                        argv[0]);
+
+                return 0;
+        }
     }
-    else if (argc == 3 && strcmp(argv[1], "-d") == 0)
-    {
-        debug = 1;
-        device = argv[2];
-    }
-    else if (argc == 4 && strcmp(argv[1], "-b") == 0)
-    {
-        baudrate = atol(argv[2]);
-        device = argv[3];
-    }
-    else if (argc == 4 && strcmp(argv[1], "-r") == 0)
-    {
-        retries = atoi(argv[2]);
-        device = argv[3];
-    }
-    else if (argc == 5 && strcmp(argv[1], "-d") == 0 && strcmp(argv[2], "-b") == 0)
-    {
-        debug = 1;
-        baudrate = atol(argv[3]);
-        device = argv[4];
-    }
-    else if (argc == 5 && strcmp(argv[1], "-d") == 0 && strcmp(argv[2], "-r") == 0)
-    {
-        debug = 1;
-        retries = atoi(argv[3]);
-        device = argv[4];
-    }
-    else if (argc == 6 && strcmp(argv[1], "-b") == 0 && strcmp(argv[3], "-r") == 0)
-    {
-        baudrate = atol(argv[2]);
-        retries = atoi(argv[4]);
-        device = argv[5];
-    }
-    else if (argc == 7 && strcmp(argv[1], "-d") == 0 && strcmp(argv[2], "-b") == 0 && strcmp(argv[4], "-r") == 0)
-    {
-        debug = 1;
-        baudrate = atol(argv[3]);
-        retries = atoi(argv[5]);
-        device = argv[6];
-    }
-    else
-    {
-        fprintf(stderr,"usage: %s [-d] [-b BAUDRATE] [-r RETRIES] device\n", argv[0]);
+
+    if (optind >= argc) {
+        fprintf(stderr,"usage: %s [-d] [-b BAUDRATE] [-r RETRIES] [-t TIMEOUT] device\n",
+                argv[0]);
+
         return 0;
     }
 
+    device = argv[optind];
+
     if ((handle = mbus_context_serial(device)) == NULL)
     {
         fprintf(stderr,"Scan failed: Could not initialize M-Bus context: %s\n",  mbus_error_str());
@@ -132,6 +116,12 @@ main(int argc, char **argv)
         return 1;
     }
 
+    if (mbus_context_set_option(handle, MBUS_OPTION_TIMEOUT_OFFSET, timeout) == -1)
+    {
+        fprintf(stderr,"Failed to set timeout offset\n");
+        return 1;
+    }
+
     if (mbus_serial_set_baudrate(handle, baudrate) == -1)
     {
         fprintf(stderr,"Failed to set baud rate.\n");

mbus/mbus-protocol-aux.c

@@ -1519,6 +1519,7 @@ mbus_context_serial(const char *device)
 
     handle->max_data_retry = 3;
     handle->max_search_retry = 1;
+    handle->timeout_offset = 0;
     handle->is_serial = 1;
     handle->purge_first_frame = MBUS_FRAME_PURGE_M2S;
     handle->auxdata = serial_data;
@@ -1567,6 +1568,7 @@ mbus_context_tcp(const char *host, uint16_t port)
 
     handle->max_data_retry = 3;
     handle->max_search_retry = 1;
+    handle->timeout_offset = 0;
     handle->is_serial = 0;
     handle->purge_first_frame = MBUS_FRAME_PURGE_M2S;
     handle->auxdata = tcp_data;
@@ -1652,6 +1654,13 @@ mbus_context_set_option(mbus_handle * handle, mbus_context_option option, long v
                 return 0;
             }
             break;
+        case MBUS_OPTION_TIMEOUT_OFFSET:
+            if ((value >= 0) && (value <= 100))
+            {
+                handle->timeout_offset = value;
+                return 0;
+            }
+            break;
         case MBUS_OPTION_PURGE_FIRST_FRAME:
             if ((value == MBUS_FRAME_PURGE_NONE) ||
                 (value == MBUS_FRAME_PURGE_M2S)  ||

mbus/mbus-protocol-aux.h

@@ -87,6 +87,7 @@ typedef struct _mbus_handle {
     int fd;
     int max_data_retry;
     int max_search_retry;
+    unsigned int timeout_offset;
     char purge_first_frame;
     char is_serial; /**< _handle type (non zero for serial) */
     int (*open) (struct _mbus_handle *handle);
@@ -154,7 +155,8 @@ typedef struct _mbus_record {
 typedef enum _mbus_context_option {
     MBUS_OPTION_MAX_DATA_RETRY,  /**< option defines the maximum attempts of data request retransmission */
     MBUS_OPTION_MAX_SEARCH_RETRY,  /**< option defines the maximum attempts of search request retransmission */
-    MBUS_OPTION_PURGE_FIRST_FRAME  /**< option controls the echo cancelation for mbus_recv_frame */
+    MBUS_OPTION_PURGE_FIRST_FRAME,  /**< option controls the echo cancelation for mbus_recv_frame */
+    MBUS_OPTION_TIMEOUT_OFFSET,  /**< option defines the additional timeout offset */
 } mbus_context_option;
 
 /**

mbus/mbus-serial.c

@@ -72,13 +72,10 @@ mbus_serial_connect(mbus_handle *handle)
     // between the end of a master send telegram and the beginning of the response telegram of the slave shall be
     // between 11 bit times and (330 bit times + 50ms).
     //
-    // Nowadays the usage of USB to serial adapter is very common, which could
-    // result in additional delay of 100 ms in worst case.
-    //
-    // For 2400Bd this means (330 + 11) / 2400 + 0.15 = 292 ms (added 11 bit periods to receive first byte).
-    // I.e. timeout of 0.3s seems appropriate for 2400Bd.
+    // For 2400Bd this means (330 + 11) / 2400 + 0.05 = 188.75 ms (added 11 bit periods to receive first byte).
+    // I.e. timeout of 0.2s seems appropriate for 2400Bd.
 
-    term->c_cc[VTIME] = (cc_t) 3; // Timeout in 1/10 sec
+    term->c_cc[VTIME] = (cc_t) 2 + handle->timeout_offset; // Timeout in 1/10 sec
 
     cfsetispeed(term, B2400);
     cfsetospeed(term, B2400);
@@ -116,48 +113,51 @@ mbus_serial_set_baudrate(mbus_handle *handle, long baudrate)
     {
         case 300:
             speed = B300;
-            serial_data->t.c_cc[VTIME] = (cc_t) 13; // Timeout in 1/10 sec
+            serial_data->t.c_cc[VTIME] = (cc_t) 12; // Timeout in 1/10 sec
             break;
 
         case 600:
             speed = B600;
-            serial_data->t.c_cc[VTIME] = (cc_t) 8;  // Timeout in 1/10 sec
+            serial_data->t.c_cc[VTIME] = (cc_t) 6;  // Timeout in 1/10 sec
             break;
 
         case 1200:
             speed = B1200;
-            serial_data->t.c_cc[VTIME] = (cc_t) 5;  // Timeout in 1/10 sec
+            serial_data->t.c_cc[VTIME] = (cc_t) 4;  // Timeout in 1/10 sec
             break;
 
         case 2400:
             speed = B2400;
-            serial_data->t.c_cc[VTIME] = (cc_t) 3;  // Timeout in 1/10 sec
+            serial_data->t.c_cc[VTIME] = (cc_t) 2;  // Timeout in 1/10 sec
             break;
 
         case 4800:
             speed = B4800;
-            serial_data->t.c_cc[VTIME] = (cc_t) 3;  // Timeout in 1/10 sec
+            serial_data->t.c_cc[VTIME] = (cc_t) 2;  // Timeout in 1/10 sec
             break;
 
         case 9600:
             speed = B9600;
-            serial_data->t.c_cc[VTIME] = (cc_t) 2;  // Timeout in 1/10 sec
+            serial_data->t.c_cc[VTIME] = (cc_t) 1;  // Timeout in 1/10 sec
             break;
 
         case 19200:
             speed = B19200;
-            serial_data->t.c_cc[VTIME] = (cc_t) 2;  // Timeout in 1/10 sec
+            serial_data->t.c_cc[VTIME] = (cc_t) 1;  // Timeout in 1/10 sec
             break;
 
         case 38400:
             speed = B38400;
-            serial_data->t.c_cc[VTIME] = (cc_t) 2;  // Timeout in 1/10 sec
+            serial_data->t.c_cc[VTIME] = (cc_t) 1;  // Timeout in 1/10 sec
             break;
 
        default:
             return -1; // unsupported baudrate
     }
 
+    // Add timeout offset for additional delay
+    serial_data->t.c_cc[VTIME] += handle->timeout_offset;
+
     // Set input baud rate
     if (cfsetispeed(&(serial_data->t), speed) != 0)
     {