remove static iSerial buffers

Author: facchinm

hardware/arduino/avr/cores/arduino/PluggableUSB.cpp

@@ -50,16 +50,15 @@ int PluggableUSB_::getDescriptor(USBSetup& setup)
 	return 0;
 }
 
-char* PluggableUSB_::getShortName(void)
+uint8_t PluggableUSB_::getShortName(char* _iSerialNum, uint8_t max_len)
 {
-	char* ret = 0;
-	memset(_iSerialNum, 0, sizeof(_iSerialNum));
+	uint8_t ret = 0;
+	memset(_iSerialNum, 0, max_len);
 	PluggableUSBModule* node;
-	for (node = rootNode; node; node = node->next) {
-		ret = node->getShortName();
-		memcpy(&_iSerialNum[strlen(_iSerialNum)], ret, strlen(ret));
+	for (node = rootNode; node && ret < max_len; node = node->next) {
+		ret += node->getShortName(&_iSerialNum[ret]);
 	}
-	return _iSerialNum;
+	return ret;
 }
 
 bool PluggableUSB_::setup(USBSetup& setup)

hardware/arduino/avr/cores/arduino/PluggableUSB.h

@@ -35,7 +35,7 @@ class PluggableUSBModule {
   virtual bool setup(USBSetup& setup) = 0;
   virtual int getInterface(uint8_t* interfaceCount) = 0;
   virtual int getDescriptor(USBSetup& setup) = 0;
-  virtual char* getShortName(void) = 0;
+  virtual uint8_t getShortName(char* name) { name[0] = 'A'+pluggedInterface; return 1; }
 
   uint8_t pluggedInterface;
   uint8_t pluggedEndpoint;
@@ -56,12 +56,11 @@ class PluggableUSB_ {
   int getInterface(uint8_t* interfaceCount);
   int getDescriptor(USBSetup& setup);
   bool setup(USBSetup& setup);
-  char* getShortName(void);
+  uint8_t getShortName(char* _iSerialNum, uint8_t max_len);
 
 private:
   uint8_t lastIf;
   uint8_t lastEp;
-  char _iSerialNum[20] = {0};
   PluggableUSBModule* rootNode;
 };
 

hardware/arduino/avr/cores/arduino/USBCore.cpp

@@ -504,7 +504,8 @@ bool SendDescriptor(USBSetup& setup)
 		}
 		else if (setup.wValueL == ISERIAL) {
 #ifdef PLUGGABLE_USB_ENABLED
-			char* name = PluggableUSB().getShortName();
+			char name[ISERIAL_MAX_LEN];
+			PluggableUSB().getShortName(name, sizeof(name));
 			return USB_SendStringDescriptor((uint8_t*)name, strlen(name), 0);
 #endif
 		}

hardware/arduino/avr/cores/arduino/USBDesc.h

@@ -24,6 +24,8 @@
 #define USB_ENDPOINTS 5 // AtMegaxxU2
 #endif
 
+#define ISERIAL_MAX_LEN     20
+
 #define CDC_INTERFACE_COUNT	2
 #define CDC_ENPOINT_COUNT	3
 

hardware/arduino/avr/libraries/HID/HID.cpp

@@ -57,14 +57,13 @@ int HID_::getDescriptor(USBSetup& setup)
 	return total;
 }
 
-char* HID_::getShortName()
+uint8_t HID_::getShortName(char* name)
 {
-	static char name[7] = {0};
 	char num[3];
 	memcpy(name, "HID", 3);
 	itoa(descriptorSize, num, 10);
 	memcpy(&name[3], num, 3);
-	return name;
+	return strlen(name);
 }
 
 void HID_::AppendDescriptor(HIDSubDescriptor *node)

hardware/arduino/avr/libraries/HID/HID.h

@@ -96,7 +96,7 @@ class HID_ : public PluggableUSBModule
   int getInterface(uint8_t* interfaceCount);
   int getDescriptor(USBSetup& setup);
   bool setup(USBSetup& setup);
-  char* getShortName(void);
+  uint8_t getShortName(char* name);
 
 private:
   uint8_t epType[1];