Added operationmode to list controllers (-L)

include/light.h

   LIGHT_ADD,
   LIGHT_SUB,
   LIGHT_PRINT_HELP,   /* Prints help and exits  */
-  LIGHT_PRINT_VERSION /* Prints version info and exits */
+  LIGHT_PRINT_VERSION, /* Prints version info and exits */
+  LIGHT_LIST_CTRL
 } LIGHT_OP_MODE;
 
 typedef enum LIGHT_VAL_MODE {
 
 LIGHT_BOOL light_setMinCap(char const *controller, unsigned long v);
 
+LIGHT_BOOL light_listControllers();
+
 #endif /* LIGHT_H */

src/light.c

 
   unsigned long specLen = 0;
 
-  while((currFlag = getopt(argc, argv, "HhVGSAUbmcas:prv:")) != -1)
+  while((currFlag = getopt(argc, argv, "HhVGSAULbmcas:prv:")) != -1)
   {
     switch(currFlag)
     {
         ASSERT_OPSET();
         light_Configuration.operationMode = LIGHT_SUB;
         break;
+      case 'L':
+        ASSERT_OPSET();
+        light_Configuration.operationMode = LIGHT_LIST_CTRL;
 
       /* -- Targets -- */
       case 'b':
   printf("  -G:\t\tGet value (default)\n");
   printf("  -S:\t\tSet value\n");
   printf("  -A:\t\tAdd value\n");
-  printf("  -U:\t\tSubtract value\n\n");
+  printf("  -U:\t\tSubtract value\n");
+  printf("  -L:\t\tList controllers\n\n");
   
   printf("Targets (can not be used in conjunction):\n");
   printf("  -b:\t\tBrightness (default)\n  \t\tUsed with [GSAU]\n\n");
     return FALSE;
   }
 
-  if(light_Configuration.operationMode == LIGHT_PRINT_HELP || light_Configuration.operationMode == LIGHT_PRINT_VERSION)
+  /* Just return true for operation modes that do not need initialization */
+  if(light_Configuration.operationMode == LIGHT_PRINT_HELP || light_Configuration.operationMode == LIGHT_PRINT_VERSION || light_Configuration.operationMode == LIGHT_LIST_CTRL)
   {
       return TRUE;
   }
     return TRUE;
   }
 
+  if(light_Configuration.operationMode == LIGHT_LIST_CTRL)
+  {
+    /* listControllers() can return FALSE, but only if it does not find any controllers. That is not enough for an unsuccessfull run. */
+    light_listControllers();
+    return TRUE;
+  }
+
   /* Prepare variables */
 
   /* -- First, get the current, min and max values directly from controller/configuration (raw values) */
         case LIGHT_GET:
         case LIGHT_PRINT_HELP:
         case LIGHT_PRINT_VERSION:
+        case LIGHT_LIST_CTRL:
           break;
       }
 
   free(mincapPath);
   return TRUE;
 }
+
+LIGHT_BOOL light_listControllers()
+{
+  LIGHT_BOOL foundController = FALSE;
+
+  while(light_iterateControllers())
+  {
+    if(!foundController)
+    {
+      foundController = TRUE;
+    }
+
+    printf("%s\n", light_currentController);
+  }
+
+  if(!foundController)
+  {
+    LIGHT_WARN("no controllers found, either check your system or your permissions");
+    return FALSE;
+  }
+
+  return TRUE;
+}