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diff --git a/scripts/lib/mic/utils/BmapCreate.py b/scripts/lib/mic/utils/BmapCreate.py
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+""" 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()