[OE-core] [PATCH 08/10] wic: implement 'wic write' command
Ed Bartosh
ed.bartosh at linux.intel.com
Fri Aug 25 13:41:43 UTC 2017
This command writes image to the media or another file with
the possibility to expand partitions to fill free target space.
Signed-off-by: Ed Bartosh <ed.bartosh at linux.intel.com>
---
scripts/lib/wic/engine.py | 142 +++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 141 insertions(+), 1 deletion(-)
diff --git a/scripts/lib/wic/engine.py b/scripts/lib/wic/engine.py
index 3c1f0d3..303f323 100644
--- a/scripts/lib/wic/engine.py
+++ b/scripts/lib/wic/engine.py
@@ -31,6 +31,8 @@
import logging
import os
import tempfile
+import json
+import subprocess
from collections import namedtuple, OrderedDict
from distutils.spawn import find_executable
@@ -340,6 +342,143 @@ class Disk:
raise err
self._put_part_image(pnum)
+ def write(self, target, expand):
+ """Write disk image to the media or file."""
+ def write_sfdisk_script(outf, parts):
+ for key, val in parts['partitiontable'].items():
+ if key in ("partitions", "device", "firstlba", "lastlba"):
+ continue
+ if key == "id":
+ key = "label-id"
+ outf.write("{}: {}\n".format(key, val))
+ outf.write("\n")
+ for part in parts['partitiontable']['partitions']:
+ line = ''
+ for name in ('attrs', 'name', 'size', 'type', 'uuid'):
+ if name == 'size' and part['type'] == 'f':
+ # don't write size for extended partition
+ continue
+ val = part.get(name)
+ if val:
+ line += '{}={}, '.format(name, val)
+ if line:
+ line = line[:-2] # strip ', '
+ if part.get('bootable'):
+ line += ' ,bootable'
+ outf.write("{}\n".format(line))
+ outf.flush()
+
+ def read_ptable(path):
+ out = exec_cmd("{} -dJ {}".format(self.sfdisk, path))
+ return json.loads(out)
+
+ def write_ptable(parts, target):
+ with tempfile.NamedTemporaryFile(prefix="wic-sfdisk-", mode='w') as outf:
+ write_sfdisk_script(outf, parts)
+ cmd = "{} --no-reread {} < {} 2>/dev/null".format(self.sfdisk, target, outf.name)
+ try:
+ subprocess.check_output(cmd, shell=True)
+ except subprocess.CalledProcessError as err:
+ raise WicError("Can't run '{}' command: {}".format(cmd, err))
+
+ if expand is None:
+ sparse_copy(self.imagepath, target)
+ else:
+ # copy first sectors that may contain bootloader
+ sparse_copy(self.imagepath, target, length=2048 * self._lsector_size)
+
+ # copy source partition table to the target
+ parts = read_ptable(self.imagepath)
+ write_ptable(parts, target)
+
+ # get size of unpartitioned space
+ free = None
+ for line in exec_cmd("{} -F {}".format(self.sfdisk, target)).splitlines():
+ if line.startswith("Unpartitioned space ") and line.endswith("sectors"):
+ free = int(line.split()[-2])
+ if free is None:
+ raise WicError("Can't get size of unpartitioned space")
+
+ # calculate expanded partitions sizes
+ sizes = {}
+ for num, part in enumerate(parts['partitiontable']['partitions'], 1):
+ if num in expand:
+ if expand[num] != 0: # don't resize partition if size is set to 0
+ sectors = expand[num] // self._lsector_size
+ free -= sectors - part['size']
+ part['size'] = sectors
+ sizes[num] = sectors
+ elif part['type'] != 'f':
+ sizes[num] = -1
+
+ for num, part in enumerate(parts['partitiontable']['partitions'], 1):
+ if sizes.get(num) == -1:
+ part['size'] += free // len(sizes)
+
+ # write resized partition table to the target
+ write_ptable(parts, target)
+
+ # read resized partition table
+ parts = read_ptable(target)
+
+ # copy partitions content
+ for num, part in enumerate(parts['partitiontable']['partitions'], 1):
+ pnum = str(num)
+ fstype = self.partitions[pnum].fstype
+
+ # copy unchanged partition
+ if part['size'] == self.partitions[pnum].size // self._lsector_size:
+ logger.info("copying unchanged partition {}".format(pnum))
+ sparse_copy(self._get_part_image(pnum), target, seek=part['start'] * self._lsector_size)
+ continue
+
+ # resize or re-create partitions
+ if fstype.startswith('ext') or fstype.startswith('fat') or \
+ fstype.startswith('linux-swap'):
+
+ partfname = None
+ with tempfile.NamedTemporaryFile(prefix="wic-part{}-".format(pnum)) as partf:
+ partfname = partf.name
+
+ if fstype.startswith('ext'):
+ logger.info("resizing ext partition {}".format(pnum))
+ partimg = self._get_part_image(pnum)
+ sparse_copy(partimg, partfname)
+ exec_cmd("{} -pf {}".format(self.e2fsck, partfname))
+ exec_cmd("{} {} {}s".format(\
+ self.resize2fs, partfname, part['size']))
+ elif fstype.startswith('fat'):
+ logger.info("copying content of the fat partition {}".format(pnum))
+ with tempfile.TemporaryDirectory(prefix='wic-fatdir-') as tmpdir:
+ # copy content to the temporary directory
+ cmd = "{} -snompi {} :: {}".format(self.mcopy,
+ self._get_part_image(pnum),
+ tmpdir)
+ exec_cmd(cmd)
+ # create new msdos partition
+ label = part.get("name")
+ label_str = "-n {}".format(label) if label else ''
+
+ cmd = "{} {} -C {} {}".format(self.mkdosfs, label_str, partfname,
+ part['size'])
+ exec_cmd(cmd)
+ # copy content from the temporary directory to the new partition
+ cmd = "{} -snompi {} {}/* ::".format(self.mcopy, partfname, tmpdir)
+ exec_cmd(cmd, as_shell=True)
+ elif fstype.startswith('linux-swap'):
+ logger.info("creating swap partition {}".format(pnum))
+ label = part.get("name")
+ label_str = "-L {}".format(label) if label else ''
+ uuid = part.get("uuid")
+ uuid_str = "-U {}".format(uuid) if uuid else ''
+ with open(partfname, 'w') as sparse:
+ os.ftruncate(sparse.fileno(), part['size'] * self._lsector_size)
+ exec_cmd("{} {} {} {}".format(self.mkswap, label_str, uuid_str, partfname))
+ sparse_copy(partfname, target, seek=part['start'] * self._lsector_size)
+ os.unlink(partfname)
+ elif part['type'] != 'f':
+ logger.warn("skipping partition {}: unsupported fstype {}".format(pnum, fstype))
+
def wic_ls(args, native_sysroot):
"""List contents of partitioned image or vfat partition."""
disk = Disk(args.path.image, native_sysroot)
@@ -374,7 +513,8 @@ def wic_write(args, native_sysroot):
"""
Write image to a target device.
"""
- pass
+ disk = Disk(args.image, native_sysroot, ('fat', 'ext', 'swap'))
+ disk.write(args.target, args.expand)
def find_canned(scripts_path, file_name):
"""
--
2.1.4
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