TrashCode.md

static void FillSlotMetadata(app_slot_metadata_t *slots, int num_slots) { for(int i = 0; i < num_slots; i++) { slots[i].slot_address = (APP_SLOT_START_ADDR + i * APP_SLOT_SIZE); slots[i].is_valid = 0;

	uint32_t *slotStart = (uint32_t *)slots[i].slot_address;

	if(*slotStart == APP_MAGIC_NUMBER)
	{
		slots[i].is_valid = 1;
	}
}

}

static void FillCodeMetadata(app_slot_metadata_t *slots, app_code_metadata_t *codes, int num_slots) { for(int i = 0; i < num_slots; i++) { if(slots[i].is_valid) { codes[i].id = *(volatile uint32_t *)(APP_SLOT_START_ADDR + (i * APP_SLOT_SIZE) + 0); codes[i].size = *(volatile uint32_t *)(APP_SLOT_START_ADDR + (i * APP_SLOT_SIZE) + 1); codes[i].version = *(volatile uint32_t *)(APP_SLOT_START_ADDR + (i * APP_SLOT_SIZE) + 2); codes[i].crc = *(volatile uint32_t *)(APP_SLOT_START_ADDR + (i * APP_SLOT_SIZE) + 3); codes[i].timestamp = *(volatile uint32_t *)(APP_SLOT_START_ADDR + (i * APP_SLOT_SIZE) + 4); codes[i].start_addr = (uint32_t)(APP_SLOT_START_ADDR + (i * APP_SLOT_SIZE) + 10); } } }

static void VerifyAppChecksum(app_code_metadata_t *codes, int num_slots) { for(int i = 0; i < num_slots; i++) { const uint32_t app_code_start= *(const uint32_t *)(codes[i].start_addr); uint32_t app_crc = CRC_Calculate((const uint32_t *)app_code_start, codes[i].size/4); if(app_crc != codes[i].crc) { codes[i].valid = 0; } else { codes[i].valid = 1; } } }

static void ShowAvailableApplications(app_code_metadata_t *codes, int num_slots) { printf("S.No.\tApplication\tSize\tVersion\tTimestamp\n\r"); for(int i = 0; i < num_slots; i++) { printf("%d\t%s\t%d\t%d\t%d\n\r", i+1, codes[i].application_name, (int)codes[i].size, (int)codes[i].version, (int)codes[i].timestamp); } printf("\n\nChoose the Application to Boot, else latest version will be loaded.\n\r"); }

static void ChooseApplication(app_code_metadata_t *codes, int num_slots) { uint8_t option; printf("[info] Available Applications in Storage:\n\r"); ShowAvailableApplications(codes, APP_SLOT_COUNT); scanf("%d", &option); return option;

}

static void FindApplications(void) { static app_code_metadata_t applicationCodeMetadata[3]; static app_slot_metadata_t applicationSlotMetadata[3];

FillSlotMetadata(applicationSlotMetadata, APP_SLOT_COUNT);
FillCodeMetadata(applicationSlotMetadata, applicationCodeMetadata, APP_SLOT_COUNT);
VerifyAppChecksum(applicationCodeMetadata, APP_SLOT_COUNT);
ChooseApplication(applicationCodeMetadata, APP_SLOT_COUNT);

}

uint32_t BOOT_LocateApplication(uint32_t app_id_address) {

FindApplications();
uint32_t appID = *(volatile uint32_t *)app_id_address;
if(appID != APP_ID)
{
	printf("\033[0;31m[error] Application missing at: 0x%08X\033[0m\n\r", (unsigned int)app_id_address);
	return 0;
}
printf("[info] Application found at: 0x%08X\n\r", (unsigned int)app_id_address);
BOOT_SaveMetadata();
return applicationMetadata.size;

}

static void BOOT_FirmwareUpdate(void) {

}

bool BOOT_VerifyApplication(uint32_t app_size) { uint32_t app_words = applicationMetadata.size/4; uint32_t appCRC = applicationMetadata.crc; const uint32_t appCODE = *(const uint32_t *)APP_CODE_START; uint32_t calculated_CRC = CRC_Calculate((const uint32_t *)appCODE, app_words);

if(calculated_CRC != appCRC)
{
	printf("\033[0;31m[error] Application Verification failed: Checksum error.\033[0m\n\r");
	return false;
}

printf("[info] Application Verification success: Checksum pass.\n\r");
return true;

}

void BOOT_LoadApplication() { uint32_t app_code_start = APP_CODE_START; uint32_t *app_vector_table = (uint32_t *)app_code_start; uint32_t app_stack_pointer = app_vector_table[0]; uint32_t app_reset_handler = app_vector_table[1];

__disable_irq();

BOOT_DeInit();

SCB->VTOR = app_code_start;
__set_MSP(app_stack_pointer);

void (*reset_handler)(void) = (void (*)(void))app_reset_handler;
reset_handler();
while(1);

}

void BOOT_HandleErrors(void) { printf("\033[0;31m[error] Application Failed to Load.\033[0m\n\r"); }