Each coupler is now identified by a 12 bytest long UUID.

coupler/opc-ua-server/server.c

@@ -26,12 +26,31 @@
 #include "common.h"
 #include "mod_io_i2c.h"
 #include "mod_io_opc_ua.h"
+#include <time.h>
 
 
 // The default port of OPC-UA server
 const int DEFAULT_OPC_UA_PORT = 4840;
 const int DEFAULT_MODE = 0;
 
+
+char *randomString(size_t length)
+{
+    static char charset[] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
+    char *randomString = NULL;
+    if (length) {
+        randomString = malloc(sizeof(char) * (length +1));
+        if (randomString) {
+            for (int n = 0;n < length;n++) {
+                int key = rand() % (int)(sizeof(charset) -1);
+                randomString[n] = charset[key];
+            }
+            randomString[length] = '\0';
+        }
+    }
+    return randomString;
+}
+
 // CLI arguments handling
 const char *argp_program_version = "OSIE OPC-UA coupler 0.0.1";
 const char *argp_program_bug_address = "ivan@nexedi.com";
@@ -47,6 +66,7 @@ static struct argp_option options[] = {
   {"password",    'w', "", 0, "Password."},
   {"key",         'k', "", 0, "x509 key."},
   {"certificate", 'c', "", 0, "X509 certificate."},
+  {"uuid",        'i', "", 0, "UUID of coupler"},
   {0}
 };
 
@@ -60,6 +80,7 @@ struct arguments
     char *password;
     char *key;
     char *certificate;
+    char *uuid;
 };
 
 static error_t parse_opt(int key, char *arg, struct argp_state *state)
@@ -90,6 +111,9 @@ static error_t parse_opt(int key, char *arg, struct argp_state *state)
     case 'k':
 	    arguments->key = arg;
 	    break;
+    case 'i':
+	    arguments->uuid = arg;
+	    break;
     case ARGP_KEY_ARG:
 	    return 0;
     default: 
@@ -125,13 +149,22 @@ int main(int argc, char **argv)
     arguments.password = "";
     arguments.key = "";
     arguments.certificate = "";
+    arguments.uuid = "";
     argp_parse(&argp, argc, argv, 0, 0, &arguments);
+
+    // if no uuid define, generate a random one
+    if (!strlen(arguments.uuid)) {
+      arguments.uuid = randomString(12);
+    }
+
     printf("Mode=%d\n", arguments.mode);
     printf("Listening port=%d\n", arguments.port);
     printf("Block device=%s\n", arguments.device);
     printf("Slave address list=%s\n", arguments.slave_address_list);
     printf("key=%s\n", arguments.key);
     printf("certificate=%s\n", arguments.certificate);
+    printf("UUID=%s\n", arguments.uuid);
+
 
     // transfer to global variables (CLI input)
     I2C_VIRTUAL_MODE = arguments.mode;