lib/efi_selftest/initrddump.c - platform/external/u-boot - Gitiles

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Copyright 2020, Heinrich Schuchardt <xypron.glpk@gmx.de>
  *
  * initrddump.efi saves the initial RAM disk provided via the
  * EFI_LOAD_FILE2_PROTOCOL.
  */

 #include <common.h>
 #include <efi_api.h>
 #include <efi_load_initrd.h>

 #define BUFFER_SIZE 64
 #define ESC 0x17

 #define efi_size_in_pages(size) (((size) + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT)

 static struct efi_system_table *systable;
 static struct efi_boot_services *bs;
 static struct efi_simple_text_output_protocol *cerr;
 static struct efi_simple_text_output_protocol *cout;
 static struct efi_simple_text_input_protocol *cin;
 static const efi_guid_t loaded_image_guid = EFI_LOADED_IMAGE_PROTOCOL_GUID;
 static const efi_guid_t guid_simple_file_system_protocol =
 					EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID;
 static const efi_guid_t load_file2_guid = EFI_LOAD_FILE2_PROTOCOL_GUID;
 static efi_handle_t handle;

 /*
  * Device path defined by Linux to identify the handle providing the
  * EFI_LOAD_FILE2_PROTOCOL used for loading the initial ramdisk.
  */
 static const struct efi_initrd_dp initrd_dp = {
 	.vendor = {
 		{
 		   DEVICE_PATH_TYPE_MEDIA_DEVICE,
 		   DEVICE_PATH_SUB_TYPE_VENDOR_PATH,
 		   sizeof(initrd_dp.vendor),
 		},
 		EFI_INITRD_MEDIA_GUID,
 	},
 	.end = {
 		DEVICE_PATH_TYPE_END,
 		DEVICE_PATH_SUB_TYPE_END,
 		sizeof(initrd_dp.end),
 	}
 };

 /**
  * print() - print string
  *
  * @string:	text
  */
 static void print(u16 *string)
 {
 	cout->output_string(cout, string);
 }

 /**
  * error() - print error string
  *
  * @string:	error text
  */
 static void error(u16 *string)
 {
 	cout->set_attribute(cout, EFI_LIGHTRED | EFI_BACKGROUND_BLACK);
 	print(string);
 	cout->set_attribute(cout, EFI_LIGHTBLUE | EFI_BACKGROUND_BLACK);
 }

 /*
  * printx() - print hexadecimal number
  *
  * @val:	value to print;
  * @prec:	minimum number of digits to print
  */
 static void printx(u64 val, u32 prec)
 {
 	int i;
 	u16 c;
 	u16 buf[16];
 	u16 *pos = buf;

 	for (i = 2 * sizeof(val) - 1; i >= 0; --i) {
 		c = (val >> (4 * i)) & 0x0f;
 		if (c || pos != buf || !i || i < prec) {
 			c += '0';
 			if (c > '9')
 				c += 'a' - '9' - 1;
 			*pos++ = c;
 		}
 	}
 	*pos = 0;
 	print(buf);
 }

 /**
  * efi_input_yn() - get answer to yes/no question
  *
  * Return:
  * y or Y
  *     EFI_SUCCESS
  * n or N
  *     EFI_ACCESS_DENIED
  * ESC
  *     EFI_ABORTED
  */
 static efi_status_t efi_input_yn(void)
 {
 	struct efi_input_key key = {0};
 	efi_uintn_t index;
 	efi_status_t ret;

 	/* Drain the console input */
 	ret = cin->reset(cin, true);
 	for (;;) {
 		ret = bs->wait_for_event(1, &cin->wait_for_key, &index);
 		if (ret != EFI_SUCCESS)
 			continue;
 		ret = cin->read_key_stroke(cin, &key);
 		if (ret != EFI_SUCCESS)
 			continue;
 		switch (key.scan_code) {
 		case 0x17: /* Escape */
 			return EFI_ABORTED;
 		default:
 			break;
 		}
 		/* Convert to lower case */
 		switch (key.unicode_char | 0x20) {
 		case 'y':
 			return EFI_SUCCESS;
 		case 'n':
 			return EFI_ACCESS_DENIED;
 		default:
 			break;
 		}
 	}
 }

 /**
  * efi_input() - read string from console
  *
  * @buffer:		input buffer
  * @buffer_size:	buffer size
  * Return:		status code
  */
 static efi_status_t efi_input(u16 *buffer, efi_uintn_t buffer_size)
 {
 	struct efi_input_key key = {0};
 	efi_uintn_t index;
 	efi_uintn_t pos = 0;
 	u16 outbuf[2] = L" ";
 	efi_status_t ret;

 	/* Drain the console input */
 	ret = cin->reset(cin, true);
 	*buffer = 0;
 	for (;;) {
 		ret = bs->wait_for_event(1, &cin->wait_for_key, &index);
 		if (ret != EFI_SUCCESS)
 			continue;
 		ret = cin->read_key_stroke(cin, &key);
 		if (ret != EFI_SUCCESS)
 			continue;
 		switch (key.scan_code) {
 		case 0x17: /* Escape */
 			print(L"\r\nAborted\r\n");
 			return EFI_ABORTED;
 		default:
 			break;
 		}
 		switch (key.unicode_char) {
 		case 0x08: /* Backspace */
 			if (pos) {
 				buffer[pos--] = 0;
 				print(L"\b \b");
 			}
 			break;
 		case 0x0a: /* Linefeed */
 		case 0x0d: /* Carriage return */
 			print(L"\r\n");
 			return EFI_SUCCESS;
 		default:
 			break;
 		}
 		/* Ignore surrogate codes */
 		if (key.unicode_char >= 0xD800 && key.unicode_char <= 0xDBFF)
 			continue;
 		if (key.unicode_char >= 0x20 &&
 		    pos < buffer_size - 1) {
 			*outbuf = key.unicode_char;
 			buffer[pos++] = key.unicode_char;
 			buffer[pos] = 0;
 			print(outbuf);
 		}
 	}
 }

 /**
  * skip_whitespace() - skip over leading whitespace
  *
  * @pos:	UTF-16 string
  * Return:	pointer to first non-whitespace
  */
 static u16 *skip_whitespace(u16 *pos)
 {
 	for (; *pos && *pos <= 0x20; ++pos)
 		;
 	return pos;
 }

 /**
  * starts_with() - check if @string starts with @keyword
  *
  * @string:	string to search for keyword
  * @keyword:	keyword to be searched
  * Return:	true fi @string starts with the keyword
  */
 static bool starts_with(u16 *string, u16 *keyword)
 {
 	for (; *keyword; ++string, ++keyword) {
 		if (*string != *keyword)
 			return false;
 	}
 	return true;
 }

 /**
  * do_help() - print help
  */
 static void do_help(void)
 {
 	error(L"load          - show length and CRC32 of initial RAM disk\r\n");
 	error(L"save <initrd> - save initial RAM disk to file\r\n");
 	error(L"exit          - exit the shell\r\n");
 }

 /**
  * get_initrd() - read initial RAM disk via EFI_LOAD_FILE2_PROTOCOL
  *
  * @initrd:		on return buffer with initial RAM disk
  * @initrd_size:	size of initial RAM disk
  * Return:		status code
  */
 static efi_status_t get_initrd(void **initrd, efi_uintn_t *initrd_size)
 {
 	struct efi_device_path *dp = (struct efi_device_path *)&initrd_dp;
 	struct efi_load_file_protocol *load_file2_prot;
 	u64 buffer;
 	efi_handle_t handle;
 	efi_status_t ret;

 	*initrd = NULL;
 	*initrd_size = 0;
 	ret = bs->locate_device_path(&load_file2_guid, &dp, &handle);
 	if (ret != EFI_SUCCESS) {
 		error(L"Load File2 protocol not found\r\n");
 		return ret;
 	}
 	ret = bs->handle_protocol(handle, &load_file2_guid,
 				 (void **)&load_file2_prot);
 	ret = load_file2_prot->load_file(load_file2_prot, dp, false,
 					 initrd_size, NULL);
 	if (ret != EFI_BUFFER_TOO_SMALL) {
 		error(L"Load File2 protocol does not provide file length\r\n");
 		return EFI_LOAD_ERROR;
 	}
 	ret = bs->allocate_pages(EFI_ALLOCATE_ANY_PAGES, EFI_LOADER_DATA,
 				 efi_size_in_pages(*initrd_size), &buffer);
 	if (ret != EFI_SUCCESS) {
 		error(L"Out of memory\r\n");
 		return ret;
 	}
 	*initrd = (void *)buffer;
 	ret = load_file2_prot->load_file(load_file2_prot, dp, false,
 					 initrd_size, *initrd);
 	if (ret != EFI_SUCCESS) {
 		error(L"Load File2 protocol failed to provide file\r\n");
 		bs->free_pages(buffer, efi_size_in_pages(*initrd_size));
 		return EFI_LOAD_ERROR;
 	}
 	return ret;
 }

 /**
  * do_load() - load initial RAM disk and display CRC32 and length
  *
  * @filename:	file name
  * Return:	status code
  */
 static efi_status_t do_load(void)
 {
 	void *initrd;
 	efi_uintn_t initrd_size;
 	u32 crc32;
 	efi_uintn_t ret;

 	ret =  get_initrd(&initrd, &initrd_size);
 	if (ret != EFI_SUCCESS)
 		return ret;
 	print(L"length: 0x");
 	printx(initrd_size, 1);
 	print(L"\r\n");

 	ret = bs->calculate_crc32(initrd, initrd_size, &crc32);
 	if (ret != EFI_SUCCESS) {
 		error(L"Calculating CRC32 failed\r\n");
 		return EFI_LOAD_ERROR;
 	}
 	print(L"crc32: 0x");
 	printx(crc32, 8);
 	print(L"\r\n");

 	return EFI_SUCCESS;
 }

 /**
  * do_save() - save initial RAM disk
  *
  * @filename:	file name
  * Return:	status code
  */
 static efi_status_t do_save(u16 *filename)
 {
 	struct efi_loaded_image *loaded_image;
 	struct efi_simple_file_system_protocol *file_system;
 	struct efi_file_handle *root, *file;
 	void *initrd;
 	efi_uintn_t initrd_size;
 	efi_uintn_t ret;

 	ret = get_initrd(&initrd, &initrd_size);
 	if (ret != EFI_SUCCESS)
 		return ret;

 	filename = skip_whitespace(filename);

 	ret = bs->open_protocol(handle, &loaded_image_guid,
 				(void **)&loaded_image, NULL, NULL,
 				EFI_OPEN_PROTOCOL_GET_PROTOCOL);
 	if (ret != EFI_SUCCESS) {
 		error(L"Loaded image protocol not found\r\n");
 		goto out;
 	}

 	/* Open the simple file system protocol */
 	ret = bs->open_protocol(loaded_image->device_handle,
 				&guid_simple_file_system_protocol,
 				(void **)&file_system, NULL, NULL,
 				EFI_OPEN_PROTOCOL_GET_PROTOCOL);
 	if (ret != EFI_SUCCESS) {
 		error(L"Failed to open simple file system protocol\r\n");
 		goto out;
 	}

 	/* Open volume */
 	ret = file_system->open_volume(file_system, &root);
 	if (ret != EFI_SUCCESS) {
 		error(L"Failed to open volume\r\n");
 		goto out;
 	}
 	/* Check if file already exists */
 	ret = root->open(root, &file, filename, EFI_FILE_MODE_READ, 0);
 	if (ret == EFI_SUCCESS) {
 		file->close(file);
 		print(L"Overwrite existing file (y/n)? ");
 		ret = efi_input_yn();
 		print(L"\r\n");
 		if (ret != EFI_SUCCESS) {
 			root->close(root);
 			error(L"Aborted by user\r\n");
 			goto out;
 		}
 	}

 	/* Create file */
 	ret = root->open(root, &file, filename,
 			 EFI_FILE_MODE_READ | EFI_FILE_MODE_WRITE |
 			 EFI_FILE_MODE_CREATE, EFI_FILE_ARCHIVE);
 	if (ret == EFI_SUCCESS) {
 		/* Write file */
 		ret = file->write(file, &initrd_size, initrd);
 		if (ret != EFI_SUCCESS) {
 			error(L"Failed to write file\r\n");
 		} else {
 			print(filename);
 			print(L" written\r\n");
 		}
 		file->close(file);
 	} else {
 		error(L"Failed to open file\r\n");
 	}
 	root->close(root);

 out:
 	if (initrd)
 		bs->free_pages((uintptr_t)initrd,
 			       efi_size_in_pages(initrd_size));
 	return ret;
 }

 /**
  * efi_main() - entry point of the EFI application.
  *
  * @handle:	handle of the loaded image
  * @systab:	system table
  * @return:	status code
  */
 efi_status_t EFIAPI efi_main(efi_handle_t image_handle,
 			     struct efi_system_table *systab)
 {
 	handle = image_handle;
 	systable = systab;
 	cerr = systable->std_err;
 	cout = systable->con_out;
 	cin = systable->con_in;
 	bs = systable->boottime;

 	cout->set_attribute(cout, EFI_LIGHTBLUE | EFI_BACKGROUND_BLACK);
 	cout->clear_screen(cout);
 	cout->set_attribute(cout, EFI_WHITE | EFI_BACKGROUND_BLACK);
 	print(L"INITRD Dump\r\n========\r\n\r\n");
 	cout->set_attribute(cout, EFI_LIGHTBLUE | EFI_BACKGROUND_BLACK);

 	for (;;) {
 		u16 command[BUFFER_SIZE];
 		u16 *pos;
 		efi_uintn_t ret;

 		print(L"=> ");
 		ret = efi_input(command, sizeof(command));
 		if (ret == EFI_ABORTED)
 			break;
 		pos = skip_whitespace(command);
 		if (starts_with(pos, L"exit"))
 			break;
 		else if (starts_with(pos, L"load"))
 			do_load();
 		else if (starts_with(pos, L"save "))
 			do_save(pos + 5);
 		else
 			do_help();
 	}

 	cout->set_attribute(cout, EFI_LIGHTGRAY | EFI_BACKGROUND_BLACK);
 	cout->clear_screen(cout);
 	return EFI_SUCCESS;
 }
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* Copyright 2020, Heinrich Schuchardt <xypron.glpk@gmx.de>
	*
	* initrddump.efi saves the initial RAM disk provided via the
	* EFI_LOAD_FILE2_PROTOCOL.
	*/

	#include <common.h>
	#include <efi_api.h>
	#include <efi_load_initrd.h>

	#define BUFFER_SIZE 64
	#define ESC 0x17

	#define efi_size_in_pages(size) (((size) + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT)

	static struct efi_system_table *systable;
	static struct efi_boot_services *bs;
	static struct efi_simple_text_output_protocol *cerr;
	static struct efi_simple_text_output_protocol *cout;
	static struct efi_simple_text_input_protocol *cin;
	static const efi_guid_t loaded_image_guid = EFI_LOADED_IMAGE_PROTOCOL_GUID;
	static const efi_guid_t guid_simple_file_system_protocol =
	EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID;
	static const efi_guid_t load_file2_guid = EFI_LOAD_FILE2_PROTOCOL_GUID;
	static efi_handle_t handle;

	/*
	* Device path defined by Linux to identify the handle providing the
	* EFI_LOAD_FILE2_PROTOCOL used for loading the initial ramdisk.
	*/
	static const struct efi_initrd_dp initrd_dp = {
	.vendor = {
	{
	DEVICE_PATH_TYPE_MEDIA_DEVICE,
	DEVICE_PATH_SUB_TYPE_VENDOR_PATH,
	sizeof(initrd_dp.vendor),
	},
	EFI_INITRD_MEDIA_GUID,
	},
	.end = {
	DEVICE_PATH_TYPE_END,
	DEVICE_PATH_SUB_TYPE_END,
	sizeof(initrd_dp.end),
	}
	};

	/**
	* print() - print string
	*
	* @string: text
	*/
	static void print(u16 *string)
	{
	cout->output_string(cout, string);
	}

	/**
	* error() - print error string
	*
	* @string: error text
	*/
	static void error(u16 *string)
	{
	cout->set_attribute(cout, EFI_LIGHTRED \| EFI_BACKGROUND_BLACK);
	print(string);
	cout->set_attribute(cout, EFI_LIGHTBLUE \| EFI_BACKGROUND_BLACK);
	}

	/*
	* printx() - print hexadecimal number
	*
	* @val: value to print;
	* @prec: minimum number of digits to print
	*/
	static void printx(u64 val, u32 prec)
	{
	int i;
	u16 c;
	u16 buf[16];
	u16 *pos = buf;

	for (i = 2 * sizeof(val) - 1; i >= 0; --i) {
	c = (val >> (4 * i)) & 0x0f;
	if (c \|\| pos != buf \|\| !i \|\| i < prec) {
	c += '0';
	if (c > '9')
	c += 'a' - '9' - 1;
	*pos++ = c;
	}
	}
	*pos = 0;
	print(buf);
	}

	/**
	* efi_input_yn() - get answer to yes/no question
	*
	* Return:
	* y or Y
	* EFI_SUCCESS
	* n or N
	* EFI_ACCESS_DENIED
	* ESC
	* EFI_ABORTED
	*/
	static efi_status_t efi_input_yn(void)
	{
	struct efi_input_key key = {0};
	efi_uintn_t index;
	efi_status_t ret;

	/* Drain the console input */
	ret = cin->reset(cin, true);
	for (;;) {
	ret = bs->wait_for_event(1, &cin->wait_for_key, &index);
	if (ret != EFI_SUCCESS)
	continue;
	ret = cin->read_key_stroke(cin, &key);
	if (ret != EFI_SUCCESS)
	continue;
	switch (key.scan_code) {
	case 0x17: /* Escape */
	return EFI_ABORTED;
	default:
	break;
	}
	/* Convert to lower case */
	switch (key.unicode_char \| 0x20) {
	case 'y':
	return EFI_SUCCESS;
	case 'n':
	return EFI_ACCESS_DENIED;
	default:
	break;
	}
	}
	}

	/**
	* efi_input() - read string from console
	*
	* @buffer: input buffer
	* @buffer_size: buffer size
	* Return: status code
	*/
	static efi_status_t efi_input(u16 *buffer, efi_uintn_t buffer_size)
	{
	struct efi_input_key key = {0};
	efi_uintn_t index;
	efi_uintn_t pos = 0;
	u16 outbuf[2] = L" ";
	efi_status_t ret;

	/* Drain the console input */
	ret = cin->reset(cin, true);
	*buffer = 0;
	for (;;) {
	ret = bs->wait_for_event(1, &cin->wait_for_key, &index);
	if (ret != EFI_SUCCESS)
	continue;
	ret = cin->read_key_stroke(cin, &key);
	if (ret != EFI_SUCCESS)
	continue;
	switch (key.scan_code) {
	case 0x17: /* Escape */
	print(L"\r\nAborted\r\n");
	return EFI_ABORTED;
	default:
	break;
	}
	switch (key.unicode_char) {
	case 0x08: /* Backspace */
	if (pos) {
	buffer[pos--] = 0;
	print(L"\b \b");
	}
	break;
	case 0x0a: /* Linefeed */
	case 0x0d: /* Carriage return */
	print(L"\r\n");
	return EFI_SUCCESS;
	default:
	break;
	}
	/* Ignore surrogate codes */
	if (key.unicode_char >= 0xD800 && key.unicode_char <= 0xDBFF)
	continue;
	if (key.unicode_char >= 0x20 &&
	pos < buffer_size - 1) {
	*outbuf = key.unicode_char;
	buffer[pos++] = key.unicode_char;
	buffer[pos] = 0;
	print(outbuf);
	}
	}
	}

	/**
	* skip_whitespace() - skip over leading whitespace
	*
	* @pos: UTF-16 string
	* Return: pointer to first non-whitespace
	*/
	static u16 skip_whitespace(u16 pos)
	{
	for (; pos && pos <= 0x20; ++pos)
	;
	return pos;
	}

	/**
	* starts_with() - check if @string starts with @keyword
	*
	* @string: string to search for keyword
	* @keyword: keyword to be searched
	* Return: true fi @string starts with the keyword
	*/
	static bool starts_with(u16 string, u16 keyword)
	{
	for (; *keyword; ++string, ++keyword) {
	if (string != keyword)
	return false;
	}
	return true;
	}

	/**
	* do_help() - print help
	*/
	static void do_help(void)
	{
	error(L"load - show length and CRC32 of initial RAM disk\r\n");
	error(L"save <initrd> - save initial RAM disk to file\r\n");
	error(L"exit - exit the shell\r\n");
	}

	/**
	* get_initrd() - read initial RAM disk via EFI_LOAD_FILE2_PROTOCOL
	*
	* @initrd: on return buffer with initial RAM disk
	* @initrd_size: size of initial RAM disk
	* Return: status code
	*/
	static efi_status_t get_initrd(void *initrd, efi_uintn_t initrd_size)
	{
	struct efi_device_path dp = (struct efi_device_path )&initrd_dp;
	struct efi_load_file_protocol *load_file2_prot;
	u64 buffer;
	efi_handle_t handle;
	efi_status_t ret;

	*initrd = NULL;
	*initrd_size = 0;
	ret = bs->locate_device_path(&load_file2_guid, &dp, &handle);
	if (ret != EFI_SUCCESS) {
	error(L"Load File2 protocol not found\r\n");
	return ret;
	}
	ret = bs->handle_protocol(handle, &load_file2_guid,
	(void **)&load_file2_prot);
	ret = load_file2_prot->load_file(load_file2_prot, dp, false,
	initrd_size, NULL);
	if (ret != EFI_BUFFER_TOO_SMALL) {
	error(L"Load File2 protocol does not provide file length\r\n");
	return EFI_LOAD_ERROR;
	}
	ret = bs->allocate_pages(EFI_ALLOCATE_ANY_PAGES, EFI_LOADER_DATA,
	efi_size_in_pages(*initrd_size), &buffer);
	if (ret != EFI_SUCCESS) {
	error(L"Out of memory\r\n");
	return ret;
	}
	initrd = (void )buffer;
	ret = load_file2_prot->load_file(load_file2_prot, dp, false,
	initrd_size, *initrd);
	if (ret != EFI_SUCCESS) {
	error(L"Load File2 protocol failed to provide file\r\n");
	bs->free_pages(buffer, efi_size_in_pages(*initrd_size));
	return EFI_LOAD_ERROR;
	}
	return ret;
	}

	/**
	* do_load() - load initial RAM disk and display CRC32 and length
	*
	* @filename: file name
	* Return: status code
	*/
	static efi_status_t do_load(void)
	{
	void *initrd;
	efi_uintn_t initrd_size;
	u32 crc32;
	efi_uintn_t ret;

	ret = get_initrd(&initrd, &initrd_size);
	if (ret != EFI_SUCCESS)
	return ret;
	print(L"length: 0x");
	printx(initrd_size, 1);
	print(L"\r\n");

	ret = bs->calculate_crc32(initrd, initrd_size, &crc32);
	if (ret != EFI_SUCCESS) {
	error(L"Calculating CRC32 failed\r\n");
	return EFI_LOAD_ERROR;
	}
	print(L"crc32: 0x");
	printx(crc32, 8);
	print(L"\r\n");

	return EFI_SUCCESS;
	}

	/**
	* do_save() - save initial RAM disk
	*
	* @filename: file name
	* Return: status code
	*/
	static efi_status_t do_save(u16 *filename)
	{
	struct efi_loaded_image *loaded_image;
	struct efi_simple_file_system_protocol *file_system;
	struct efi_file_handle root, file;
	void *initrd;
	efi_uintn_t initrd_size;
	efi_uintn_t ret;

	ret = get_initrd(&initrd, &initrd_size);
	if (ret != EFI_SUCCESS)
	return ret;

	filename = skip_whitespace(filename);

	ret = bs->open_protocol(handle, &loaded_image_guid,
	(void **)&loaded_image, NULL, NULL,
	EFI_OPEN_PROTOCOL_GET_PROTOCOL);
	if (ret != EFI_SUCCESS) {
	error(L"Loaded image protocol not found\r\n");
	goto out;
	}

	/* Open the simple file system protocol */
	ret = bs->open_protocol(loaded_image->device_handle,
	&guid_simple_file_system_protocol,
	(void **)&file_system, NULL, NULL,
	EFI_OPEN_PROTOCOL_GET_PROTOCOL);
	if (ret != EFI_SUCCESS) {
	error(L"Failed to open simple file system protocol\r\n");
	goto out;
	}

	/* Open volume */
	ret = file_system->open_volume(file_system, &root);
	if (ret != EFI_SUCCESS) {
	error(L"Failed to open volume\r\n");
	goto out;
	}
	/* Check if file already exists */
	ret = root->open(root, &file, filename, EFI_FILE_MODE_READ, 0);
	if (ret == EFI_SUCCESS) {
	file->close(file);
	print(L"Overwrite existing file (y/n)? ");
	ret = efi_input_yn();
	print(L"\r\n");
	if (ret != EFI_SUCCESS) {
	root->close(root);
	error(L"Aborted by user\r\n");
	goto out;
	}
	}

	/* Create file */
	ret = root->open(root, &file, filename,
	EFI_FILE_MODE_READ \| EFI_FILE_MODE_WRITE \|
	EFI_FILE_MODE_CREATE, EFI_FILE_ARCHIVE);
	if (ret == EFI_SUCCESS) {
	/* Write file */
	ret = file->write(file, &initrd_size, initrd);
	if (ret != EFI_SUCCESS) {
	error(L"Failed to write file\r\n");
	} else {
	print(filename);
	print(L" written\r\n");
	}
	file->close(file);
	} else {
	error(L"Failed to open file\r\n");
	}
	root->close(root);

	out:
	if (initrd)
	bs->free_pages((uintptr_t)initrd,
	efi_size_in_pages(initrd_size));
	return ret;
	}

	/**
	* efi_main() - entry point of the EFI application.
	*
	* @handle: handle of the loaded image
	* @systab: system table
	* @return: status code
	*/
	efi_status_t EFIAPI efi_main(efi_handle_t image_handle,
	struct efi_system_table *systab)
	{
	handle = image_handle;
	systable = systab;
	cerr = systable->std_err;
	cout = systable->con_out;
	cin = systable->con_in;
	bs = systable->boottime;

	cout->set_attribute(cout, EFI_LIGHTBLUE \| EFI_BACKGROUND_BLACK);
	cout->clear_screen(cout);
	cout->set_attribute(cout, EFI_WHITE \| EFI_BACKGROUND_BLACK);
	print(L"INITRD Dump\r\n========\r\n\r\n");
	cout->set_attribute(cout, EFI_LIGHTBLUE \| EFI_BACKGROUND_BLACK);

	for (;;) {
	u16 command[BUFFER_SIZE];
	u16 *pos;
	efi_uintn_t ret;

	print(L"=> ");
	ret = efi_input(command, sizeof(command));
	if (ret == EFI_ABORTED)
	break;
	pos = skip_whitespace(command);
	if (starts_with(pos, L"exit"))
	break;
	else if (starts_with(pos, L"load"))
	do_load();
	else if (starts_with(pos, L"save "))
	do_save(pos + 5);
	else
	do_help();
	}

	cout->set_attribute(cout, EFI_LIGHTGRAY \| EFI_BACKGROUND_BLACK);
	cout->clear_screen(cout);
	return EFI_SUCCESS;
	}