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source: mainline/tools/mkfat.py@ 609243f4

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lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export

Last change on this file since 609243f4 was cc1a727, checked in by Martin Sucha <sucha14@…>, 14 years ago
Add support for ext2 to be used as RAM disk format
Property mode set to `100755`
File size: 13.1 KB

Rev	Line
[5749372]	1	#!/usr/bin/env python
	2	#
	3	# Copyright (c) 2008 Martin Decky
	4	# All rights reserved.
	5	#
	6	# Redistribution and use in source and binary forms, with or without
	7	# modification, are permitted provided that the following conditions
	8	# are met:
	9	#
	10	# - Redistributions of source code must retain the above copyright
	11	# notice, this list of conditions and the following disclaimer.
	12	# - Redistributions in binary form must reproduce the above copyright
	13	# notice, this list of conditions and the following disclaimer in the
	14	# documentation and/or other materials provided with the distribution.
	15	# - The name of the author may not be used to endorse or promote products
	16	# derived from this software without specific prior written permission.
	17	#
	18	# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
	19	# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	20	# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	21	# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	22	# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	23	# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	24	# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	25	# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	26	# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	27	# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	28	#
[3c80f2b]	29
[5749372]	30	"""
	31	FAT creator
	32	"""
	33
	34	import sys
	35	import os
	36	import random
	37	import xstruct
[04619ba]	38	import array
[cc1a727]	39	from imgutil import *
[700eaa9]	40
[04619ba]	41	def subtree_size(root, cluster_size, dirent_size):
[700eaa9]	42	"Recursive directory walk and calculate size"
	43
	44	size = 0
[95b730c2]	45	files = 2
[700eaa9]	46
[cc1a727]	47	for item in listdir_items(root):
	48	if item.is_file:
	49	size += align_up(item.size, cluster_size)
[700eaa9]	50	files += 1
[cc1a727]	51	elif item.is_dir:
	52	size += subtree_size(item.path, cluster_size, dirent_size)
[700eaa9]	53	files += 1
	54
[04619ba]	55	return size + align_up(files * dirent_size, cluster_size)
[700eaa9]	56
	57	def root_entries(root):
	58	"Return number of root directory entries"
	59
	60	return len(os.listdir(root))
	61
[cc1a727]	62	def write_file(item, outf, cluster_size, data_start, fat, reserved_clusters):
[04619ba]	63	"Store the contents of a file"
	64
	65	prev = -1
[95b730c2]	66	first = 0
[04619ba]	67
[cc1a727]	68	for data in chunks(item, cluster_size):
[04619ba]	69	empty_cluster = fat.index(0)
	70	fat[empty_cluster] = 0xffff
[95b730c2]	71
[04619ba]	72	if (prev != -1):
	73	fat[prev] = empty_cluster
	74	else:
	75	first = empty_cluster
	76
	77	prev = empty_cluster
	78
[95b730c2]	79	outf.seek(data_start + (empty_cluster - reserved_clusters) * cluster_size)
[04619ba]	80	outf.write(data)
	81
[cc1a727]	82	return first, item.size
[04619ba]	83
[95b730c2]	84	def write_directory(directory, outf, cluster_size, data_start, fat, reserved_clusters, dirent_size, empty_cluster):
	85	"Store the contents of a directory"
	86
	87	length = len(directory)
	88	size = length * dirent_size
	89	prev = -1
	90	first = 0
	91
	92	i = 0
	93	rd = 0;
	94	while (rd < size):
	95	if (prev != -1):
	96	empty_cluster = fat.index(0)
	97	fat[empty_cluster] = 0xffff
	98	fat[prev] = empty_cluster
	99	else:
	100	first = empty_cluster
	101
	102	prev = empty_cluster
	103
[28f4adb]	104	data = bytes()
[95b730c2]	105	data_len = 0
	106	while ((i < length) and (data_len < cluster_size)):
	107	if (i == 0):
	108	directory[i].cluster = empty_cluster
	109
	110	data += directory[i].pack()
	111	data_len += dirent_size
	112	i += 1
	113
	114	outf.seek(data_start + (empty_cluster - reserved_clusters) * cluster_size)
	115	outf.write(data)
	116	rd += len(data)
	117
	118	return first, size
	119
[04619ba]	120	DIR_ENTRY = """little:
	121	char name[8] /* file name */
	122	char ext[3] /* file extension */
	123	uint8_t attr /* file attributes */
[a248234]	124	uint8_t lcase /* file name case (NT extension) */
[04619ba]	125	uint8_t ctime_fine /* create time (fine resolution) */
	126	uint16_t ctime /* create time */
	127	uint16_t cdate /* create date */
	128	uint16_t adate /* access date */
	129	padding[2] /* EA-index */
	130	uint16_t mtime /* modification time */
	131	uint16_t mdate /* modification date */
	132	uint16_t cluster /* first cluster */
	133	uint32_t size /* file size */
	134	"""
	135
[95b730c2]	136	DOT_DIR_ENTRY = """little:
	137	uint8_t signature /* 0x2e signature */
	138	char name[7] /* empty */
	139	char ext[3] /* empty */
	140	uint8_t attr /* file attributes */
	141	padding[1] /* reserved for NT */
	142	uint8_t ctime_fine /* create time (fine resolution) */
	143	uint16_t ctime /* create time */
	144	uint16_t cdate /* create date */
	145	uint16_t adate /* access date */
	146	padding[2] /* EA-index */
	147	uint16_t mtime /* modification time */
	148	uint16_t mdate /* modification date */
	149	uint16_t cluster /* first cluster */
	150	uint32_t size /* file size */
	151	"""
	152
	153	DOTDOT_DIR_ENTRY = """little:
	154	uint8_t signature[2] /* 0x2e signature */
	155	char name[6] /* empty */
	156	char ext[3] /* empty */
	157	uint8_t attr /* file attributes */
	158	padding[1] /* reserved for NT */
	159	uint8_t ctime_fine /* create time (fine resolution) */
	160	uint16_t ctime /* create time */
	161	uint16_t cdate /* create date */
	162	uint16_t adate /* access date */
	163	padding[2] /* EA-index */
	164	uint16_t mtime /* modification time */
	165	uint16_t mdate /* modification date */
	166	uint16_t cluster /* first cluster */
	167	uint32_t size /* file size */
	168	"""
	169
[04619ba]	170	def mangle_fname(name):
	171	# FIXME: filter illegal characters
[95b730c2]	172	parts = name.split('.')
	173
[042fbe0]	174	if len(parts) > 0:
[95b730c2]	175	fname = parts[0]
	176	else:
	177	fname = ''
[042fbe0]	178
	179	if len(fname) > 8:
	180	sys.stdout.write("mkfat.py: error: Directory entry " + name +
	181	" base name is longer than 8 characters\n")
	182	sys.exit(1);
	183
[95b730c2]	184	return (fname + ' ').upper()[0:8]
[04619ba]	185
	186	def mangle_ext(name):
	187	# FIXME: filter illegal characters
[95b730c2]	188	parts = name.split('.')
	189
[042fbe0]	190	if len(parts) > 1:
[95b730c2]	191	ext = parts[1]
	192	else:
	193	ext = ''
	194
[042fbe0]	195	if len(parts) > 2:
	196	sys.stdout.write("mkfat.py: error: Directory entry " + name +
	197	" has more than one extension\n")
	198	sys.exit(1);
	199
	200	if len(ext) > 3:
	201	sys.stdout.write("mkfat.py: error: Directory entry " + name +
	202	" extension is longer than 3 characters\n")
	203	sys.exit(1);
	204
[95b730c2]	205	return (ext + ' ').upper()[0:3]
[04619ba]	206
	207	def create_dirent(name, directory, cluster, size):
	208	dir_entry = xstruct.create(DIR_ENTRY)
	209
[432f68a]	210	dir_entry.name = mangle_fname(name).encode('ascii')
	211	dir_entry.ext = mangle_ext(name).encode('ascii')
[04619ba]	212
	213	if (directory):
	214	dir_entry.attr = 0x30
	215	else:
	216	dir_entry.attr = 0x20
	217
[a248234]	218	dir_entry.lcase = 0x18
[04619ba]	219	dir_entry.ctime_fine = 0 # FIXME
	220	dir_entry.ctime = 0 # FIXME
	221	dir_entry.cdate = 0 # FIXME
	222	dir_entry.adate = 0 # FIXME
	223	dir_entry.mtime = 0 # FIXME
	224	dir_entry.mdate = 0 # FIXME
	225	dir_entry.cluster = cluster
[95b730c2]	226
	227	if (directory):
	228	dir_entry.size = 0
	229	else:
	230	dir_entry.size = size
	231
	232	return dir_entry
	233
	234	def create_dot_dirent(empty_cluster):
	235	dir_entry = xstruct.create(DOT_DIR_ENTRY)
	236
	237	dir_entry.signature = 0x2e
[432f68a]	238	dir_entry.name = b' '
	239	dir_entry.ext = b' '
[95b730c2]	240	dir_entry.attr = 0x10
	241
	242	dir_entry.ctime_fine = 0 # FIXME
	243	dir_entry.ctime = 0 # FIXME
	244	dir_entry.cdate = 0 # FIXME
	245	dir_entry.adate = 0 # FIXME
	246	dir_entry.mtime = 0 # FIXME
	247	dir_entry.mdate = 0 # FIXME
	248	dir_entry.cluster = empty_cluster
	249	dir_entry.size = 0
	250
	251	return dir_entry
	252
	253	def create_dotdot_dirent(parent_cluster):
	254	dir_entry = xstruct.create(DOTDOT_DIR_ENTRY)
	255
	256	dir_entry.signature = [0x2e, 0x2e]
[432f68a]	257	dir_entry.name = b' '
	258	dir_entry.ext = b' '
[95b730c2]	259	dir_entry.attr = 0x10
	260
	261	dir_entry.ctime_fine = 0 # FIXME
	262	dir_entry.ctime = 0 # FIXME
	263	dir_entry.cdate = 0 # FIXME
	264	dir_entry.adate = 0 # FIXME
	265	dir_entry.mtime = 0 # FIXME
	266	dir_entry.mdate = 0 # FIXME
	267	dir_entry.cluster = parent_cluster
	268	dir_entry.size = 0
[04619ba]	269
	270	return dir_entry
	271
[95b730c2]	272	def recursion(head, root, outf, cluster_size, root_start, data_start, fat, reserved_clusters, dirent_size, parent_cluster):
[04619ba]	273	"Recursive directory walk"
	274
	275	directory = []
[95b730c2]	276
	277	if (not head):
	278	# Directory cluster preallocation
	279	empty_cluster = fat.index(0)
	280	fat[empty_cluster] = 0xffff
	281
	282	directory.append(create_dot_dirent(empty_cluster))
	283	directory.append(create_dotdot_dirent(parent_cluster))
	284	else:
	285	empty_cluster = 0
	286
[cc1a727]	287	for item in listdir_items(root):
	288	if item.is_file:
	289	rv = write_file(item, outf, cluster_size, data_start, fat, reserved_clusters)
	290	directory.append(create_dirent(item.name, False, rv[0], rv[1]))
	291	elif item.is_dir:
	292	rv = recursion(False, item.path, outf, cluster_size, root_start, data_start, fat, reserved_clusters, dirent_size, empty_cluster)
	293	directory.append(create_dirent(item.name, True, rv[0], rv[1]))
[04619ba]	294
	295	if (head):
	296	outf.seek(root_start)
	297	for dir_entry in directory:
	298	outf.write(dir_entry.pack())
[95b730c2]	299	else:
	300	return write_directory(directory, outf, cluster_size, data_start, fat, reserved_clusters, dirent_size, empty_cluster)
[04619ba]	301
[5749372]	302	BOOT_SECTOR = """little:
	303	uint8_t jmp[3] /* jump instruction */
	304	char oem[8] /* OEM string */
	305	uint16_t sector /* bytes per sector */
	306	uint8_t cluster /* sectors per cluster */
	307	uint16_t reserved /* reserved sectors */
	308	uint8_t fats /* number of FATs */
	309	uint16_t rootdir /* root directory entries */
	310	uint16_t sectors /* total number of sectors */
	311	uint8_t descriptor /* media descriptor */
	312	uint16_t fat_sectors /* sectors per single FAT */
	313	uint16_t track_sectors /* sectors per track */
	314	uint16_t heads /* number of heads */
	315	uint32_t hidden /* hidden sectors */
	316	uint32_t sectors_big /* total number of sectors (if sectors == 0) */
	317
	318	/* Extended BIOS Parameter Block */
	319	uint8_t drive /* physical drive number */
	320	padding[1] /* reserved (current head) */
	321	uint8_t extboot_signature /* extended boot signature */
	322	uint32_t serial /* serial number */
	323	char label[11] /* volume label */
	324	char fstype[8] /* filesystem type */
	325	padding[448] /* boot code */
	326	uint8_t boot_signature[2] /* boot signature */
	327	"""
	328
[8bc6fcf]	329	EMPTY_SECTOR = """little:
[04619ba]	330	padding[512] /* empty sector data */
	331	"""
	332
	333	FAT_ENTRY = """little:
	334	uint16_t next /* FAT16 entry */
[8bc6fcf]	335	"""
	336
[5749372]	337	def usage(prname):
	338	"Print usage syntax"
[28f4adb]	339	print(prname + " <EXTRA_BYTES> <PATH> <IMAGE>")
[5749372]	340
	341	def main():
[14f2100]	342	if (len(sys.argv) < 4):
[5749372]	343	usage(sys.argv[0])
	344	return
	345
[14f2100]	346	if (not sys.argv[1].isdigit()):
[28f4adb]	347	print("<EXTRA_BYTES> must be a number")
[14f2100]	348	return
	349
	350	extra_bytes = int(sys.argv[1])
	351
	352	path = os.path.abspath(sys.argv[2])
[5749372]	353	if (not os.path.isdir(path)):
[28f4adb]	354	print("<PATH> must be a directory")
[5749372]	355	return
	356
[c4702798]	357	fat16_clusters = 4096
[04619ba]	358
[700eaa9]	359	sector_size = 512
	360	cluster_size = 4096
[04619ba]	361	dirent_size = 32
	362	fatent_size = 2
	363	fat_count = 2
	364	reserved_clusters = 2
	365
[f4057f5]	366	# Make sure the filesystem is large enough for FAT16
[14f2100]	367	size = subtree_size(path, cluster_size, dirent_size) + reserved_clusters * cluster_size + extra_bytes
[28f4adb]	368	while (size // cluster_size < fat16_clusters):
[ab579fa]	369	if (cluster_size > sector_size):
[28f4adb]	370	cluster_size = cluster_size // 2
[14f2100]	371	size = subtree_size(path, cluster_size, dirent_size) + reserved_clusters * cluster_size + extra_bytes
[04619ba]	372	else:
	373	size = fat16_clusters * cluster_size + reserved_clusters * cluster_size
[700eaa9]	374
[04619ba]	375	root_size = align_up(root_entries(path) * dirent_size, cluster_size)
[700eaa9]	376
[28f4adb]	377	fat_size = align_up(align_up(size, cluster_size) // cluster_size * fatent_size, sector_size)
[04619ba]	378
[28f4adb]	379	sectors = (cluster_size + fat_count * fat_size + root_size + size) // sector_size
[04619ba]	380	root_start = cluster_size + fat_count * fat_size
	381	data_start = root_start + root_size
[700eaa9]	382
[28f4adb]	383	outf = open(sys.argv[3], "wb")
[5749372]	384
	385	boot_sector = xstruct.create(BOOT_SECTOR)
	386	boot_sector.jmp = [0xEB, 0x3C, 0x90]
[28f4adb]	387	boot_sector.oem = b'MSDOS5.0'
[700eaa9]	388	boot_sector.sector = sector_size
[28f4adb]	389	boot_sector.cluster = cluster_size // sector_size
	390	boot_sector.reserved = cluster_size // sector_size
[04619ba]	391	boot_sector.fats = fat_count
[28f4adb]	392	boot_sector.rootdir = root_size // dirent_size
[de4a1cf]	393	if (sectors <= 65535):
	394	boot_sector.sectors = sectors
	395	else:
	396	boot_sector.sectors = 0
[5749372]	397	boot_sector.descriptor = 0xF8
[28f4adb]	398	boot_sector.fat_sectors = fat_size // sector_size
[700eaa9]	399	boot_sector.track_sectors = 63
	400	boot_sector.heads = 6
[5749372]	401	boot_sector.hidden = 0
[de4a1cf]	402	if (sectors > 65535):
	403	boot_sector.sectors_big = sectors
	404	else:
	405	boot_sector.sectors_big = 0
[5749372]	406
[700eaa9]	407	boot_sector.drive = 0x80
[5749372]	408	boot_sector.extboot_signature = 0x29
[0951495]	409	boot_sector.serial = random.randint(0, 0x7fffffff)
[28f4adb]	410	boot_sector.label = b'HELENOS'
	411	boot_sector.fstype = b'FAT16 '
[5749372]	412	boot_sector.boot_signature = [0x55, 0xAA]
	413
	414	outf.write(boot_sector.pack())
	415
[8bc6fcf]	416	empty_sector = xstruct.create(EMPTY_SECTOR)
	417
[04619ba]	418	# Reserved sectors
[28f4adb]	419	for i in range(1, cluster_size // sector_size):
[8bc6fcf]	420	outf.write(empty_sector.pack())
	421
	422	# FAT tables
[04619ba]	423	for i in range(0, fat_count):
[28f4adb]	424	for j in range(0, fat_size // sector_size):
[8bc6fcf]	425	outf.write(empty_sector.pack())
	426
	427	# Root directory
[28f4adb]	428	for i in range(0, root_size // sector_size):
[8bc6fcf]	429	outf.write(empty_sector.pack())
	430
	431	# Data
[28f4adb]	432	for i in range(0, size // sector_size):
[8bc6fcf]	433	outf.write(empty_sector.pack())
	434
[28f4adb]	435	fat = array.array('L', [0] * (fat_size // fatent_size))
[04619ba]	436	fat[0] = 0xfff8
	437	fat[1] = 0xffff
	438
[95b730c2]	439	recursion(True, path, outf, cluster_size, root_start, data_start, fat, reserved_clusters, dirent_size, 0)
[04619ba]	440
	441	# Store FAT
	442	fat_entry = xstruct.create(FAT_ENTRY)
	443	for i in range(0, fat_count):
	444	outf.seek(cluster_size + i * fat_size)
[28f4adb]	445	for j in range(0, fat_size // fatent_size):
[04619ba]	446	fat_entry.next = fat[j]
	447	outf.write(fat_entry.pack())
	448
[5749372]	449	outf.close()
	450
	451	if __name__ == '__main__':
	452	main()

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