add HID descriptor lenght to iSerial

Author: facchinm

Diff for: hardware/arduino/avr/cores/arduino/PluggableUSB.cpp

@@ -35,7 +35,7 @@ static u8 modules_count = 0;
 
 static PUSBListNode* rootNode = NULL;
 
-char _iSerialNum[2*MAX_MODULES] = {0};
+static char _iSerialNum[5*MAX_MODULES] = {0};
 
 int PUSB_GetInterface(u8* interfaceNum)
 {
@@ -62,10 +62,11 @@ int PUSB_GetDescriptor(int8_t t)
 char* PUSB_GetShortName()
 {
 	char* ret = 0;
+	memset(_iSerialNum, 0, sizeof(_iSerialNum));
 	PUSBListNode* node = rootNode;
 	for (u8 i=0; i<modules_count; i++) {
 		ret = node->cb->getShortName();
-		memcpy(&_iSerialNum[i*2], ret, 2);
+		memcpy(&_iSerialNum[strlen(_iSerialNum)], ret, strlen(ret));
 		node = node->next;
 	}
 	return _iSerialNum;

Diff for: hardware/arduino/avr/libraries/HID/HID.cpp

@@ -81,7 +81,11 @@ int HID_GetDescriptor(int8_t t)
 
 char* HID_GetShortName()
 {
-	static char* name = "HI";
+	static char name[5];
+	char num[3];
+	memcpy(name, "HI", 2);
+	itoa(sizeof_hidReportDescriptor, num, 10);
+	memcpy(&name[2], num, 3);
 	return name;
 }