[OE-core] [PATCH 08/35] wic: Remove bmap support
Tom Zanussi
tom.zanussi at linux.intel.com
Fri Aug 8 22:05:33 UTC 2014
wic doesn't use it, so remove it.
Signed-off-by: Tom Zanussi <tom.zanussi at linux.intel.com>
---
scripts/lib/mic/utils/BmapCreate.py | 298 ------------------------------------
1 file changed, 298 deletions(-)
delete mode 100644 scripts/lib/mic/utils/BmapCreate.py
diff --git a/scripts/lib/mic/utils/BmapCreate.py b/scripts/lib/mic/utils/BmapCreate.py
deleted file mode 100644
index 65b19a5..0000000
--- a/scripts/lib/mic/utils/BmapCreate.py
+++ /dev/null
@@ -1,298 +0,0 @@
-""" This module implements the block map (bmap) creation functionality and
-provides the corresponding API in form of the 'BmapCreate' class.
-
-The idea is that while images files may generally be very large (e.g., 4GiB),
-they may nevertheless contain only little real data, e.g., 512MiB. This data
-are files, directories, file-system meta-data, partition table, etc. When
-copying the image to the target device, you do not have to copy all the 4GiB of
-data, you can copy only 512MiB of it, which is 4 times less, so copying should
-presumably be 4 times faster.
-
-The block map file is an XML file which contains a list of blocks which have to
-be copied to the target device. The other blocks are not used and there is no
-need to copy them. The XML file also contains some additional information like
-block size, image size, count of mapped blocks, etc. There are also many
-commentaries, so it is human-readable.
-
-The image has to be a sparse file. Generally, this means that when you generate
-this image file, you should start with a huge sparse file which contains a
-single hole spanning the entire file. Then you should partition it, write all
-the data (probably by means of loop-back mounting the image or parts of it),
-etc. The end result should be a sparse file where mapped areas represent useful
-parts of the image and holes represent useless parts of the image, which do not
-have to be copied when copying the image to the target device.
-
-This module uses the FIBMAP ioctl to detect holes. """
-
-# Disable the following pylint recommendations:
-# * Too many instance attributes - R0902
-# * Too few public methods - R0903
-# pylint: disable=R0902,R0903
-
-import hashlib
-from mic.utils.misc import human_size
-from mic.utils import Fiemap
-
-# The bmap format version we generate
-SUPPORTED_BMAP_VERSION = "1.3"
-
-_BMAP_START_TEMPLATE = \
-"""<?xml version="1.0" ?>
-<!-- This file contains the block map for an image file, which is basically
- a list of useful (mapped) block numbers in the image file. In other words,
- it lists only those blocks which contain data (boot sector, partition
- table, file-system metadata, files, directories, extents, etc). These
- blocks have to be copied to the target device. The other blocks do not
- contain any useful data and do not have to be copied to the target
- device.
-
- The block map an optimization which allows to copy or flash the image to
- the image quicker than copying of flashing the entire image. This is
- because with bmap less data is copied: <MappedBlocksCount> blocks instead
- of <BlocksCount> blocks.
-
- Besides the machine-readable data, this file contains useful commentaries
- which contain human-readable information like image size, percentage of
- mapped data, etc.
-
- The 'version' attribute is the block map file format version in the
- 'major.minor' format. The version major number is increased whenever an
- incompatible block map format change is made. The minor number changes
- in case of minor backward-compatible changes. -->
-
-<bmap version="%s">
- <!-- Image size in bytes: %s -->
- <ImageSize> %u </ImageSize>
-
- <!-- Size of a block in bytes -->
- <BlockSize> %u </BlockSize>
-
- <!-- Count of blocks in the image file -->
- <BlocksCount> %u </BlocksCount>
-
-"""
-
-class Error(Exception):
- """ A class for exceptions generated by this module. We currently support
- only one type of exceptions, and we basically throw human-readable problem
- description in case of errors. """
- pass
-
-class BmapCreate:
- """ This class implements the bmap creation functionality. To generate a
- bmap for an image (which is supposedly a sparse file), you should first
- create an instance of 'BmapCreate' and provide:
-
- * full path or a file-like object of the image to create bmap for
- * full path or a file object to use for writing the results to
-
- Then you should invoke the 'generate()' method of this class. It will use
- the FIEMAP ioctl to generate the bmap. """
-
- def _open_image_file(self):
- """ Open the image file. """
-
- try:
- self._f_image = open(self._image_path, 'rb')
- except IOError as err:
- raise Error("cannot open image file '%s': %s" \
- % (self._image_path, err))
-
- self._f_image_needs_close = True
-
- def _open_bmap_file(self):
- """ Open the bmap file. """
-
- try:
- self._f_bmap = open(self._bmap_path, 'w+')
- except IOError as err:
- raise Error("cannot open bmap file '%s': %s" \
- % (self._bmap_path, err))
-
- self._f_bmap_needs_close = True
-
- def __init__(self, image, bmap):
- """ Initialize a class instance:
- * image - full path or a file-like object of the image to create bmap
- for
- * bmap - full path or a file object to use for writing the resulting
- bmap to """
-
- self.image_size = None
- self.image_size_human = None
- self.block_size = None
- self.blocks_cnt = None
- self.mapped_cnt = None
- self.mapped_size = None
- self.mapped_size_human = None
- self.mapped_percent = None
-
- self._mapped_count_pos1 = None
- self._mapped_count_pos2 = None
- self._sha1_pos = None
-
- self._f_image_needs_close = False
- self._f_bmap_needs_close = False
-
- if hasattr(image, "read"):
- self._f_image = image
- self._image_path = image.name
- else:
- self._image_path = image
- self._open_image_file()
-
- if hasattr(bmap, "read"):
- self._f_bmap = bmap
- self._bmap_path = bmap.name
- else:
- self._bmap_path = bmap
- self._open_bmap_file()
-
- self.fiemap = Fiemap.Fiemap(self._f_image)
-
- self.image_size = self.fiemap.image_size
- self.image_size_human = human_size(self.image_size)
- if self.image_size == 0:
- raise Error("cannot generate bmap for zero-sized image file '%s'" \
- % self._image_path)
-
- self.block_size = self.fiemap.block_size
- self.blocks_cnt = self.fiemap.blocks_cnt
-
- def _bmap_file_start(self):
- """ A helper function which generates the starting contents of the
- block map file: the header comment, image size, block size, etc. """
-
- # We do not know the amount of mapped blocks at the moment, so just put
- # whitespaces instead of real numbers. Assume the longest possible
- # numbers.
- mapped_count = ' ' * len(str(self.image_size))
- mapped_size_human = ' ' * len(self.image_size_human)
-
- xml = _BMAP_START_TEMPLATE \
- % (SUPPORTED_BMAP_VERSION, self.image_size_human,
- self.image_size, self.block_size, self.blocks_cnt)
- xml += " <!-- Count of mapped blocks: "
-
- self._f_bmap.write(xml)
- self._mapped_count_pos1 = self._f_bmap.tell()
-
- # Just put white-spaces instead of real information about mapped blocks
- xml = "%s or %.1f -->\n" % (mapped_size_human, 100.0)
- xml += " <MappedBlocksCount> "
-
- self._f_bmap.write(xml)
- self._mapped_count_pos2 = self._f_bmap.tell()
-
- xml = "%s </MappedBlocksCount>\n\n" % mapped_count
-
- # pylint: disable=C0301
- xml += " <!-- The checksum of this bmap file. When it is calculated, the value of\n"
- xml += " the SHA1 checksum has be zeoro (40 ASCII \"0\" symbols). -->\n"
- xml += " <BmapFileSHA1> "
-
- self._f_bmap.write(xml)
- self._sha1_pos = self._f_bmap.tell()
-
- xml = "0" * 40 + " </BmapFileSHA1>\n\n"
- xml += " <!-- The block map which consists of elements which may either be a\n"
- xml += " range of blocks or a single block. The 'sha1' attribute (if present)\n"
- xml += " is the SHA1 checksum of this blocks range. -->\n"
- xml += " <BlockMap>\n"
- # pylint: enable=C0301
-
- self._f_bmap.write(xml)
-
- def _bmap_file_end(self):
- """ A helper function which generates the final parts of the block map
- file: the ending tags and the information about the amount of mapped
- blocks. """
-
- xml = " </BlockMap>\n"
- xml += "</bmap>\n"
-
- self._f_bmap.write(xml)
-
- self._f_bmap.seek(self._mapped_count_pos1)
- self._f_bmap.write("%s or %.1f%%" % \
- (self.mapped_size_human, self.mapped_percent))
-
- self._f_bmap.seek(self._mapped_count_pos2)
- self._f_bmap.write("%u" % self.mapped_cnt)
-
- self._f_bmap.seek(0)
- sha1 = hashlib.sha1(self._f_bmap.read()).hexdigest()
- self._f_bmap.seek(self._sha1_pos)
- self._f_bmap.write("%s" % sha1)
-
- def _calculate_sha1(self, first, last):
- """ A helper function which calculates SHA1 checksum for the range of
- blocks of the image file: from block 'first' to block 'last'. """
-
- start = first * self.block_size
- end = (last + 1) * self.block_size
-
- self._f_image.seek(start)
- hash_obj = hashlib.new("sha1")
-
- chunk_size = 1024*1024
- to_read = end - start
- read = 0
-
- while read < to_read:
- if read + chunk_size > to_read:
- chunk_size = to_read - read
- chunk = self._f_image.read(chunk_size)
- hash_obj.update(chunk)
- read += chunk_size
-
- return hash_obj.hexdigest()
-
- def generate(self, include_checksums = True):
- """ Generate bmap for the image file. If 'include_checksums' is 'True',
- also generate SHA1 checksums for block ranges. """
-
- # Save image file position in order to restore it at the end
- image_pos = self._f_image.tell()
-
- self._bmap_file_start()
-
- # Generate the block map and write it to the XML block map
- # file as we go.
- self.mapped_cnt = 0
- for first, last in self.fiemap.get_mapped_ranges(0, self.blocks_cnt):
- self.mapped_cnt += last - first + 1
- if include_checksums:
- sha1 = self._calculate_sha1(first, last)
- sha1 = " sha1=\"%s\"" % sha1
- else:
- sha1 = ""
-
- if first != last:
- self._f_bmap.write(" <Range%s> %s-%s </Range>\n" \
- % (sha1, first, last))
- else:
- self._f_bmap.write(" <Range%s> %s </Range>\n" \
- % (sha1, first))
-
- self.mapped_size = self.mapped_cnt * self.block_size
- self.mapped_size_human = human_size(self.mapped_size)
- self.mapped_percent = (self.mapped_cnt * 100.0) / self.blocks_cnt
-
- self._bmap_file_end()
-
- try:
- self._f_bmap.flush()
- except IOError as err:
- raise Error("cannot flush the bmap file '%s': %s" \
- % (self._bmap_path, err))
-
- self._f_image.seek(image_pos)
-
- def __del__(self):
- """ The class destructor which closes the opened files. """
-
- if self._f_image_needs_close:
- self._f_image.close()
- if self._f_bmap_needs_close:
- self._f_bmap.close()
--
1.8.3.1
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