#!/usr/bin/env python
#
# spiffsgen is a tool used to generate a spiffs image from a directory
#
# Copyright 2019 Espressif Systems (Shanghai) PTE LTD
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http:#www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from __future__ import division
import os
import io
import math
import struct
import argparse
import ctypes
SPIFFS_PH_FLAG_USED_FINAL_INDEX = 0xF8
SPIFFS_PH_FLAG_USED_FINAL = 0xFC
SPIFFS_PH_FLAG_LEN = 1
SPIFFS_PH_IX_SIZE_LEN = 4
SPIFFS_PH_IX_OBJ_TYPE_LEN = 1
SPIFFS_TYPE_FILE = 1
# Based on typedefs under spiffs_config.h
SPIFFS_OBJ_ID_LEN = 2 # spiffs_obj_id
SPIFFS_SPAN_IX_LEN = 2 # spiffs_span_ix
SPIFFS_PAGE_IX_LEN = 2 # spiffs_page_ix
SPIFFS_BLOCK_IX_LEN = 2 # spiffs_block_ix
class SpiffsBuildConfig():
def __init__(self, page_size, page_ix_len, block_size,
block_ix_len, meta_len, obj_name_len, obj_id_len,
span_ix_len, packed, aligned, endianness, use_magic, use_magic_len):
if block_size % page_size != 0:
raise RuntimeError("block size should be a multiple of page size")
self.page_size = page_size
self.block_size = block_size
self.obj_id_len = obj_id_len
self.span_ix_len = span_ix_len
self.packed = packed
self.aligned = aligned
self.obj_name_len = obj_name_len
self.meta_len = meta_len
self.page_ix_len = page_ix_len
self.block_ix_len = block_ix_len
self.endianness = endianness
self.use_magic = use_magic
self.use_magic_len = use_magic_len
self.PAGES_PER_BLOCK = self.block_size // self.page_size
self.OBJ_LU_PAGES_PER_BLOCK = int(math.ceil(self.block_size / self.page_size * self.obj_id_len / self.page_size))
self.OBJ_USABLE_PAGES_PER_BLOCK = self.PAGES_PER_BLOCK - self.OBJ_LU_PAGES_PER_BLOCK
self.OBJ_LU_PAGES_OBJ_IDS_LIM = self.page_size // self.obj_id_len
self.OBJ_DATA_PAGE_HEADER_LEN = self.obj_id_len + self.span_ix_len + SPIFFS_PH_FLAG_LEN
pad = 4 - (4 if self.OBJ_DATA_PAGE_HEADER_LEN % 4 == 0 else self.OBJ_DATA_PAGE_HEADER_LEN % 4)
self.OBJ_DATA_PAGE_HEADER_LEN_ALIGNED = self.OBJ_DATA_PAGE_HEADER_LEN + pad
self.OBJ_DATA_PAGE_HEADER_LEN_ALIGNED_PAD = pad
self.OBJ_DATA_PAGE_CONTENT_LEN = self.page_size - self.OBJ_DATA_PAGE_HEADER_LEN
self.OBJ_INDEX_PAGES_HEADER_LEN = (self.OBJ_DATA_PAGE_HEADER_LEN_ALIGNED + SPIFFS_PH_IX_SIZE_LEN +
SPIFFS_PH_IX_OBJ_TYPE_LEN + self.obj_name_len + self.meta_len)
self.OBJ_INDEX_PAGES_OBJ_IDS_HEAD_LIM = (self.page_size - self.OBJ_INDEX_PAGES_HEADER_LEN) // self.block_ix_len
self.OBJ_INDEX_PAGES_OBJ_IDS_LIM = (self.page_size - self.OBJ_DATA_PAGE_HEADER_LEN_ALIGNED) / self.block_ix_len
class SpiffsFullError(RuntimeError):
def __init__(self, message=None):
super(SpiffsFullError, self).__init__(message)
class SpiffsPage():
_endianness_dict = {
"little": "<",
"big": ">"
}
_len_dict = {
1: "B",
2: "H",
4: "I",
8: "Q"
}
_type_dict = {
1: ctypes.c_ubyte,
2: ctypes.c_ushort,
4: ctypes.c_uint,
8: ctypes.c_ulonglong
}
def __init__(self, bix, build_config):
self.build_config = build_config
self.bix = bix
class SpiffsObjLuPage(SpiffsPage):
def __init__(self, bix, build_config):
SpiffsPage.__init__(self, bix, build_config)
self.obj_ids_limit = self.build_config.OBJ_LU_PAGES_OBJ_IDS_LIM
self.obj_ids = list()
def _calc_magic(self, blocks_lim):
# Calculate the magic value mirrorring computation done by the macro SPIFFS_MAGIC defined in
# spiffs_nucleus.h
magic = 0x20140529 ^ self.build_config.page_size
if self.build_config.use_magic_len:
magic = magic ^ (blocks_lim - self.bix)
magic = SpiffsPage._type_dict[self.build_config.obj_id_len](magic)
return magic.value
def register_page(self, page):
if not self.obj_ids_limit > 0:
raise SpiffsFullError()
obj_id = (page.obj_id, page.__class__)
self.obj_ids.append(obj_id)
self.obj_ids_limit -= 1
def to_binary(self):
global test
img = b""
for (obj_id, page_type) in self.obj_ids:
if page_type == SpiffsObjIndexPage:
obj_id ^= (1 << ((self.build_config.obj_id_len * 8) - 1))
img += struct.pack(SpiffsPage._endianness_dict[self.build_config.endianness] +
SpiffsPage._len_dict[self.build_config.obj_id_len], obj_id)
assert(len(img) <= self.build_config.page_size)
img += b"\xFF" * (self.build_config.page_size - len(img))
return img
def magicfy(self, blocks_lim):
# Only use magic value if no valid obj id has been written to the spot, which is the
# spot taken up by the last obj id on last lookup page. The parent is responsible
# for determining which is the last lookup page and calling this function.
remaining = self.obj_ids_limit
empty_obj_id_dict = {
1: 0xFF,
2: 0xFFFF,
4: 0xFFFFFFFF,
8: 0xFFFFFFFFFFFFFFFF
}
if (remaining >= 2):
for i in range(remaining):
if i == remaining - 2:
self.obj_ids.append((self._calc_magic(blocks_lim), SpiffsObjDataPage))
break
else:
self.obj_ids.append((empty_obj_id_dict[self.build_config.obj_id_len], SpiffsObjDataPage))
self.obj_ids_limit -= 1
class SpiffsObjIndexPage(SpiffsPage):
def __init__(self, obj_id, span_ix, size, name, build_config):
SpiffsPage.__init__(self, 0, build_config)
self.obj_id = obj_id
self.span_ix = span_ix
self.name = name
self.size = size
if self.span_ix == 0:
self.pages_lim = self.build_config.OBJ_INDEX_PAGES_OBJ_IDS_HEAD_LIM
else:
self.pages_lim = self.build_config.OBJ_INDEX_PAGES_OBJ_IDS_LIM
self.pages = list()
def register_page(self, page):
if not self.pages_lim > 0:
raise SpiffsFullError
self.pages.append(page.offset)
self.pages_lim -= 1
def to_binary(self):
obj_id = self.obj_id ^ (1 << ((self.build_config.obj_id_len * 8) - 1))
img = struct.pack(SpiffsPage._endianness_dict[self.build_config.endianness] +
SpiffsPage._len_dict[self.build_config.obj_id_len] +
SpiffsPage._len_dict[self.build_config.span_ix_len] +
SpiffsPage._len_dict[SPIFFS_PH_FLAG_LEN],
obj_id,
self.span_ix,
SPIFFS_PH_FLAG_USED_FINAL_INDEX)
# Add padding before the object index page specific information
img += b"\xFF" * self.build_config.OBJ_DATA_PAGE_HEADER_LEN_ALIGNED_PAD
# If this is the first object index page for the object, add filname, type
# and size information
if self.span_ix == 0:
img += struct.pack(SpiffsPage._endianness_dict[self.build_config.endianness] +
SpiffsPage._len_dict[SPIFFS_PH_IX_SIZE_LEN] +
SpiffsPage._len_dict[SPIFFS_PH_FLAG_LEN],
self.size,
SPIFFS_TYPE_FILE)
img += self.name.encode() + (b"\x00" * ((self.build_config.obj_name_len - len(self.name)) + self.build_config.meta_len))
# Finally, add the page index of daa pages
for page in self.pages:
page = page >> int(math.log(self.build_config.page_size, 2))
img += struct.pack(SpiffsPage._endianness_dict[self.build_config.endianness] +
SpiffsPage._len_dict[self.build_config.page_ix_len], page)
assert(len(img) <= self.build_config.page_size)
img += b"\xFF" * (self.build_config.page_size - len(img))
return img
class SpiffsObjDataPage(SpiffsPage):
def __init__(self, offset, obj_id, span_ix, contents, build_config):
SpiffsPage.__init__(self, 0, build_config)
self.obj_id = obj_id
self.span_ix = span_ix
self.contents = contents
self.offset = offset
def to_binary(self):
img = struct.pack(SpiffsPage._endianness_dict[self.build_config.endianness] +
SpiffsPage._len_dict[self.build_config.obj_id_len] +
SpiffsPage._len_dict[self.build_config.span_ix_len] +
SpiffsPage._len_dict[SPIFFS_PH_FLAG_LEN],
self.obj_id,
self.span_ix,
SPIFFS_PH_FLAG_USED_FINAL)
img += self.contents
assert(len(img) <= self.build_config.page_size)
img += b"\xFF" * (self.build_config.page_size - len(img))
return img
class SpiffsBlock():
def _reset(self):
self.cur_obj_index_span_ix = 0
self.cur_obj_data_span_ix = 0
self.cur_obj_id = 0
self.cur_obj_idx_page = None
def __init__(self, bix, blocks_lim, build_config):
self.build_config = build_config
self.offset = bix * self.build_config.block_size
self.remaining_pages = self.build_config.OBJ_USABLE_PAGES_PER_BLOCK
self.pages = list()
self.bix = bix
lu_pages = list()
for i in range(self.build_config.OBJ_LU_PAGES_PER_BLOCK):
page = SpiffsObjLuPage(self.bix, self.build_config)
lu_pages.append(page)
self.pages.extend(lu_pages)
self.lu_page_iter = iter(lu_pages)
self.lu_page = next(self.lu_page_iter)
self._reset()
def _register_page(self, page):
if isinstance(page, SpiffsObjDataPage):
self.cur_obj_idx_page.register_page(page) # can raise SpiffsFullError
try:
self.lu_page.register_page(page)
except SpiffsFullError:
self.lu_page = next(self.lu_page_iter)
try:
self.lu_page.register_page(page)
except AttributeError: # no next lookup page
# Since the amount of lookup pages is pre-computed at every block instance,
# this should never occur
raise RuntimeError("invalid attempt to add page to a block when there is no more space in lookup")
self.pages.append(page)
def begin_obj(self, obj_id, size, name, obj_index_span_ix=0, obj_data_span_ix=0):
if not self.remaining_pages > 0:
raise SpiffsFullError()
self._reset()
self.cur_obj_id = obj_id
self.cur_obj_index_span_ix = obj_index_span_ix
self.cur_obj_data_span_ix = obj_data_span_ix
page = SpiffsObjIndexPage(obj_id, self.cur_obj_index_span_ix, size, name, self.build_config)
self._register_page(page)
self.cur_obj_idx_page = page
self.remaining_pages -= 1
self.cur_obj_index_span_ix += 1
def update_obj(self, contents):
if not self.remaining_pages > 0:
raise SpiffsFullError()
page = SpiffsObjDataPage(self.offset + (len(self.pages) * self.build_config.page_size),
self.cur_obj_id, self.cur_obj_data_span_ix, contents, self.build_config)
self._register_page(page)
self.cur_obj_data_span_ix += 1
self.remaining_pages -= 1
def end_obj(self):
self._reset()
def is_full(self):
return self.remaining_pages <= 0
def to_binary(self, blocks_lim):
img = b""
if self.build_config.use_magic:
for (idx, page) in enumerate(self.pages):
if idx == self.build_config.OBJ_LU_PAGES_PER_BLOCK - 1:
page.magicfy(blocks_lim)
img += page.to_binary()
else:
for page in self.pages:
img += page.to_binary()
assert(len(img) <= self.build_config.block_size)
img += b"\xFF" * (self.build_config.block_size - len(img))
return img
class SpiffsFS():
def __init__(self, img_size, build_config):
if img_size % build_config.block_size != 0:
raise RuntimeError("image size should be a multiple of block size")
self.img_size = img_size
self.build_config = build_config
self.blocks = list()
self.blocks_lim = self.img_size // self.build_config.block_size
self.remaining_blocks = self.blocks_lim
self.cur_obj_id = 1 # starting object id
def _create_block(self):
if self.is_full():
raise SpiffsFullError("the image size has been exceeded")
block = SpiffsBlock(len(self.blocks), self.blocks_lim, self.build_config)
self.blocks.append(block)
self.remaining_blocks -= 1
return block
def is_full(self):
return self.remaining_blocks <= 0
def create_file(self, img_path, file_path):
contents = None
if len(img_path) > self.build_config.obj_name_len:
raise RuntimeError("object name '%s' too long" % img_path)
name = img_path
with open(file_path, "rb") as obj:
contents = obj.read()
stream = io.BytesIO(contents)
try:
block = self.blocks[-1]
block.begin_obj(self.cur_obj_id, len(contents), name)
except (IndexError, SpiffsFullError):
block = self._create_block()
block.begin_obj(self.cur_obj_id, len(contents), name)
contents_chunk = stream.read(self.build_config.OBJ_DATA_PAGE_CONTENT_LEN)
while contents_chunk:
try:
block = self.blocks[-1]
try:
# This can fail because either (1) all the pages in block have been
# used or (2) object index has been exhausted.
block.update_obj(contents_chunk)
except SpiffsFullError:
# If its (1), use the outer exception handler
if block.is_full():
raise SpiffsFullError
# If its (2), write another object index page
block.begin_obj(self.cur_obj_id, len(contents), name,
obj_index_span_ix=block.cur_obj_index_span_ix,
obj_data_span_ix=block.cur_obj_data_span_ix)
continue
except (IndexError, SpiffsFullError):
# All pages in the block have been exhausted. Create a new block, copying
# the previous state of the block to a new one for the continuation of the
# current object
prev_block = block
block = self._create_block()
block.cur_obj_id = prev_block.cur_obj_id
block.cur_obj_idx_page = prev_block.cur_obj_idx_page
block.cur_obj_data_span_ix = prev_block.cur_obj_data_span_ix
block.cur_obj_index_span_ix = prev_block.cur_obj_index_span_ix
continue
contents_chunk = stream.read(self.build_config.OBJ_DATA_PAGE_CONTENT_LEN)
block.end_obj()
self.cur_obj_id += 1
def to_binary(self):
img = b""
for block in self.blocks:
img += block.to_binary(self.blocks_lim)
bix = len(self.blocks)
if self.build_config.use_magic:
# Create empty blocks with magic numbers
while self.remaining_blocks > 0:
block = SpiffsBlock(bix, self.blocks_lim, self.build_config)
img += block.to_binary(self.blocks_lim)
self.remaining_blocks -= 1
bix += 1
else:
# Just fill remaining spaces FF's
img += "\xFF" * (self.img_size - len(img))
return img
def main():
parser = argparse.ArgumentParser(description="SPIFFS Image Generator",
formatter_class=argparse.ArgumentDefaultsHelpFormatter)
parser.add_argument("image_size",
help="Size of the created image")
parser.add_argument("base_dir",
help="Path to directory from which the image will be created")
parser.add_argument("output_file",
help="Created image output file path")
parser.add_argument("--page-size",
help="Logical page size. Set to value same as CONFIG_SPIFFS_PAGE_SIZE.",
type=int,
default=256)
parser.add_argument("--block-size",
help="Logical block size. Set to the same value as the flash chip's sector size (g_rom_flashchip.sector_size).",
type=int,
default=4096)
parser.add_argument("--obj-name-len",
help="File full path maximum length. Set to value same as CONFIG_SPIFFS_OBJ_NAME_LEN.",
type=int,
default=32)
parser.add_argument("--meta-len",
help="File metadata length. Set to value same as CONFIG_SPIFFS_META_LENGTH.",
type=int,
default=4)
parser.add_argument("--use-magic",
help="Use magic number to create an identifiable SPIFFS image. Specify if CONFIG_SPIFFS_USE_MAGIC.",
action="store_true",
default=True)
parser.add_argument("--follow-symlinks",
help="Take into account symbolic links during partition image creation.",
action="store_true",
default=False)
parser.add_argument("--use-magic-len",
help="Use position in memory to create different magic numbers for each block. Specify if CONFIG_SPIFFS_USE_MAGIC_LENGTH.",
action="store_true",
default=True)
parser.add_argument("--big-endian",
help="Specify if the target architecture is big-endian. If not specified, little-endian is assumed.",
action="store_true",
default=False)
args = parser.parse_args()
if not os.path.exists(args.base_dir):
raise RuntimeError("given base directory %s does not exist" % args.base_dir)
with open(args.output_file, "wb") as image_file:
image_size = int(args.image_size, 0)
spiffs_build_default = SpiffsBuildConfig(args.page_size, SPIFFS_PAGE_IX_LEN,
args.block_size, SPIFFS_BLOCK_IX_LEN, args.meta_len,
args.obj_name_len, SPIFFS_OBJ_ID_LEN, SPIFFS_SPAN_IX_LEN,
True, True, "big" if args.big_endian else "little",
args.use_magic, args.use_magic_len)
spiffs = SpiffsFS(image_size, spiffs_build_default)
for root, dirs, files in os.walk(args.base_dir, followlinks=args.follow_symlinks):
for f in files:
full_path = os.path.join(root, f)
spiffs.create_file("/" + os.path.relpath(full_path, args.base_dir).replace("\\", "/"), full_path)
image = spiffs.to_binary()
image_file.write(image)
if __name__ == "__main__":
main()