enhance neopixel service

hardcode pixel to 10 even for CLUE to prevent invalid len write to data

Author: hathach

libraries/BLEAdafruitService/src/services/BLEAdafruitAddressablePixel.cpp

@@ -109,7 +109,9 @@ err_t BLEAdafruitAddressablePixel::begin(uint8_t pin, uint8_t type, uint16_t buf
   // Add Characteristic
   _data.setProperties(CHR_PROPS_WRITE);
   _data.setPermission(SECMODE_NO_ACCESS, SECMODE_OPEN);
-  _data.setMaxLen(3 + bufsize); // start (2 byte) + flags (1 byte)
+  // start (2 byte) + flags (1 byte)
+  // TODO: for backward compatible with current CPB app, force to at least 10 pixels
+  _data.setMaxLen(3 + 30 /* bufsize */);
   VERIFY_STATUS( _data.begin() );
 
   // Add Characteristic
@@ -124,28 +126,36 @@ err_t BLEAdafruitAddressablePixel::begin(uint8_t pin, uint8_t type, uint16_t buf
   return ERROR_NONE;
 }
 
-//--------------------------------------------------------------------+
-// Static callbacks
-//--------------------------------------------------------------------+
-void BLEAdafruitAddressablePixel::pixel_data_write_cb(uint16_t conn_hdl, BLECharacteristic* chr, uint8_t* data, uint16_t len)
+void BLEAdafruitAddressablePixel::_pixel_write_handler(uint16_t conn_hdl, uint8_t* data, uint16_t len)
 {
   (void) conn_hdl;
 
   if (len < 3) return;
 
-  BLEAdafruitAddressablePixel& svc = (BLEAdafruitAddressablePixel&) chr->parentService();
-
   uint16_t index;
   memcpy(&index, data, 2);
   uint8_t flag = data[2];
 
-  uint8_t* buffer = svc._neo->getPixels() + index;
+  // pixel staring buffer
+  uint8_t* pixbuf = _neo->getPixels() + index;
+
+  // limit copied bytes up to strip's boundary
+  uint16_t copied_count = max16(_bufsize.read16(), index) - index;
+  copied_count = min16(len-3, copied_count);
+
+  PRINT_INT(copied_count);
 
-  memcpy(buffer, data+3, len-3);
+  if (copied_count) memcpy(pixbuf, data+3, copied_count);
 
   // show flag
-  if ( flag & 0x01 )
-  {
-    svc._neo->show();
-  }
+  if ( flag & 0x01 ) _neo->show();
+}
+
+//--------------------------------------------------------------------+
+// Static callbacks
+//--------------------------------------------------------------------+
+void BLEAdafruitAddressablePixel::pixel_data_write_cb(uint16_t conn_hdl, BLECharacteristic* chr, uint8_t* data, uint16_t len)
+{
+  BLEAdafruitAddressablePixel& svc = (BLEAdafruitAddressablePixel&) chr->parentService();
+  svc._pixel_write_handler(conn_hdl, data, len);
 }

libraries/BLEAdafruitService/src/services/BLEAdafruitAddressablePixel.h

@@ -49,6 +49,8 @@ class BLEAdafruitAddressablePixel : public BLEService
 
     err_t begin(uint8_t pin, uint8_t type, uint16_t bufsize);
 
+    void _pixel_write_handler(uint16_t conn_hdl, uint8_t* data, uint16_t len);
+
     static void pixel_data_write_cb(uint16_t conn_hdl, BLECharacteristic* chr, uint8_t* data, uint16_t len);
 };
 

variants/clue_nrf52840/variant.h

@@ -42,8 +42,8 @@ extern "C"
 
 // LEDs
 #define PIN_LED1             (17)
-#define PIN_NEOPIXEL         (18)
 #define PIN_LED2             (43)      // dual white LEDs
+#define PIN_NEOPIXEL         (18)
 
 #define LED_BUILTIN          PIN_LED1