redefining HEADER_LEN with sizeof

Author: andreagilardoni

loader/main.c

@@ -22,15 +22,15 @@ LOG_MODULE_REGISTER(sketch);
 #include <zephyr/drivers/uart.h>
 #include <zephyr/usb/usb_device.h>
 
-#define HEADER_LEN 16
-
 struct sketch_header_v1 {
 	uint8_t ver;    // @ 0x07
 	uint32_t len;   // @ 0x08
 	uint16_t magic; // @ 0x0c
 	uint8_t flags;  // @ 0x0e
 } __attribute__((packed));
 
+#define HEADER_LEN sizeof(struct sketch_header_v1)
+
 #define SKETCH_FLAG_DEBUG     0x01
 #define SKETCH_FLAG_LINKED    0x02
 #define SKETCH_FLAG_IMMEDIATE 0x04