def __save_new(self, fileobj, atoms, ilst, offset):
hdlr = Atom.render("hdlr", "\x00" * 8 + "mdirappl" + "\x00" * 9)
meta = Atom.render("meta", "\x00\x00\x00\x00" + hdlr + ilst)
moov, udta = atoms.path("moov", "udta")
insert_bytes(fileobj, len(meta), udta.offset + offset + 8)
fileobj.seek(udta.offset + offset + 8)
fileobj.write(meta)
self.__update_parents(fileobj, [moov, udta], len(meta), offset)
def save(self, filename=None, deleteid3=False):
"""Save metadata blocks to a file.
If no filename is given, the one most recently loaded is used.
"""
if filename is None:
filename = self.filename
f = open(filename, "rb+")
# Ensure we've got padding at the end, and only at the end.
# If adding makes it too large, we'll scale it down later.
self.metadata_blocks.append(Padding("\x00" * 1020))
MetadataBlock.group_padding(self.metadata_blocks)
header = self.__check_header(f)
available = self.__find_audio_offset(f) - header # "fLaC" and maybe ID3
data = MetadataBlock.writeblocks(self.metadata_blocks)
# Delete ID3v2
if deleteid3 and header > 4:
available += header - 4
header = 4
if len(data) > available:
# If we have too much data, see if we can reduce padding.
padding = self.metadata_blocks[-1]
newlength = padding.length - (len(data) - available)
if newlength > 0:
padding.length = newlength
data = MetadataBlock.writeblocks(self.metadata_blocks)
assert len(data) == available
elif len(data) < available:
# If we have too little data, increase padding.
self.metadata_blocks[-1].length += available - len(data)
data = MetadataBlock.writeblocks(self.metadata_blocks)
assert len(data) == available
if len(data) != available:
# We couldn't reduce the padding enough.
diff = len(data) - available
insert_bytes(f, diff, header)
f.seek(header - 4)
f.write("fLaC" + data)
# Delete ID3v1
if deleteid3:
try:
f.seek(-128, 2)
except IOError:
pass
else:
if f.read(3) == "TAG":
f.seek(-128, 2)
f.truncate()
def replace(klass, fileobj, old_pages, new_pages):
"""Replace old_pages with new_pages within fileobj.
old_pages must have come from reading fileobj originally.
new_pages are assumed to have the 'same' data as old_pages,
and so the serial and sequence numbers will be copied, as will
the flags for the first and last pages.
fileobj will be resized and pages renumbered as necessary. As
such, it must be opened r+b or w+b.
"""
# Number the new pages starting from the first old page.
first = old_pages[0].sequence
for page, seq in zip(new_pages, range(first, first + len(new_pages))):
page.sequence = seq
page.serial = old_pages[0].serial
new_pages[0].first = old_pages[0].first
new_pages[0].last = old_pages[0].last
new_pages[0].continued = old_pages[0].continued
new_pages[-1].first = old_pages[-1].first
new_pages[-1].last = old_pages[-1].last
new_pages[-1].complete = old_pages[-1].complete
if not new_pages[-1].complete and len(new_pages[-1].packets) == 1:
new_pages[-1].position = -1L
new_data = "".join(map(klass.write, new_pages))
# Make room in the file for the new data.
delta = len(new_data)
fileobj.seek(old_pages[0].offset, 0)
insert_bytes(fileobj, delta, old_pages[0].offset)
fileobj.seek(old_pages[0].offset, 0)
fileobj.write(new_data)
new_data_end = old_pages[0].offset + delta
# Go through the old pages and delete them. Since we shifted
# the data down the file, we need to adjust their offsets. We
# also need to go backwards, so we don't adjust the deltas of
# the other pages.
old_pages.reverse()
for old_page in old_pages:
adj_offset = old_page.offset + delta
delete_bytes(fileobj, old_page.size, adj_offset)
# Finally, if there's any discrepency in length, we need to
# renumber the pages for the logical stream.
if len(old_pages) != len(new_pages):
fileobj.seek(new_data_end, 0)
serial = new_pages[-1].serial
sequence = new_pages[-1].sequence + 1
klass.renumber(fileobj, serial, sequence)
def __save_existing(self, fileobj, atoms, path, data, offset):
# Replace the old ilst atom.
ilst = path.pop()
delta = len(data) - ilst.length
fileobj.seek(ilst.offset + offset)
if delta > 0:
insert_bytes(fileobj, delta, ilst.offset + offset)
elif delta < 0:
delete_bytes(fileobj, -delta, ilst.offset + offset)
fileobj.seek(ilst.offset + offset)
fileobj.write(data)
self.__update_parents(fileobj, path, delta, offset)
def __save_new(self, fileobj, atoms, ilst):
hdlr = Atom.render("hdlr", "\x00" * 8 + "mdirappl" + "\x00" * 9)
meta = Atom.render(
"meta", "\x00\x00\x00\x00" + hdlr + ilst + self.__pad_ilst(ilst))
try:
path = atoms.path("moov", "udta")
except KeyError:
# moov.udta not found -- create one
path = atoms.path("moov")
meta = Atom.render("udta", meta)
offset = path[-1].offset + 8
insert_bytes(fileobj, len(meta), offset)
fileobj.seek(offset)
fileobj.write(meta)
self.__update_parents(fileobj, path, len(meta))
self.__update_offsets(fileobj, atoms, len(meta), offset)
def __save_existing(self, fileobj, atoms, path, data):
# Replace the old ilst atom.
ilst = path.pop()
offset = ilst.offset
length = ilst.length
# Check for padding "free" atoms
meta = path[-1]
index = meta.children.index(ilst)
try:
prev = meta.children[index-1]
if prev.name == "free":
offset = prev.offset
length += prev.length
except IndexError:
pass
try:
next = meta.children[index+1]
if next.name == "free":
length += next.length
except IndexError:
pass
delta = len(data) - length
if delta > 0 or (delta < 0 and delta > -8):
data += self.__pad_ilst(data)
delta = len(data) - length
insert_bytes(fileobj, delta, offset)
elif delta < 0:
data += self.__pad_ilst(data, -delta - 8)
delta = 0
fileobj.seek(offset)
fileobj.write(data)
self.__update_parents(fileobj, path, delta)
self.__update_offsets(fileobj, atoms, delta, offset)