Qf|LdZddlZejedGddZy)aSimple class to read IFF chunks. An IFF chunk (used in formats such as AIFF, TIFF, RMFF (RealMedia File Format)) has the following structure: +----------------+ | ID (4 bytes) | +----------------+ | size (4 bytes) | +----------------+ | data | | ... | +----------------+ The ID is a 4-byte string which identifies the type of chunk. The size field (a 32-bit value, encoded using big-endian byte order) gives the size of the whole chunk, including the 8-byte header. Usually an IFF-type file consists of one or more chunks. The proposed usage of the Chunk class defined here is to instantiate an instance at the start of each chunk and read from the instance until it reaches the end, after which a new instance can be instantiated. At the end of the file, creating a new instance will fail with an EOFError exception. Usage: while True: try: chunk = Chunk(file) except EOFError: break chunktype = chunk.getname() while True: data = chunk.read(nbytes) if not data: pass # do something with data The interface is file-like. The implemented methods are: read, close, seek, tell, isatty. Extra methods are: skip() (called by close, skips to the end of the chunk), getname() (returns the name (ID) of the chunk) The __init__ method has one required argument, a file-like object (including a chunk instance), and one optional argument, a flag which specifies whether or not chunks are aligned on 2-byte boundaries. The default is 1, i.e. aligned. N) )removecHeZdZd dZdZdZdZdZd dZdZ d dZ d Z y )Chunkcddl}d|_||_|rd}nd}||_|j d|_t |j dkrt |j|dz|j dd|_ |r|jdz |_ d|_ |jj|_ d|_y#|j$rtdwxYw#tt f$r d|_YywxYw) NrF><LT)structclosedalignfileread chunknamelenEOFError unpack_from chunksizeerror size_readtelloffsetseekableAttributeErrorOSError)selfrr bigendian inclheaderrstrflags ,/opt/alt/python312/lib64/python3.12/chunk.py__init__zChunk.__init__8s  GG 1 t~~  "N %#// TYYq\J1MDN !^^a/DN !))..*DK!DM|| % $ %( "!DM "s,C C!C!C:9C:c|jS)z*Return the name (ID) of the current chunk.)rrs r#getnamez Chunk.getnameR ~~c|jS)z%Return the size of the current chunk.)rr&s r#getsizez Chunk.getsizeVr(r)cf|js |jd|_yy#d|_wxYw)NT)rskipr&s r#closez Chunk.closeZs.{{ # " # s' 0c2|jr tdy)NI/O operation on closed fileF)r ValueErrorr&s r#isattyz Chunk.isattyas ;;;< <r)cF|jr td|js td|dk(r||jz}n|dk(r||j z}|dks||j kDrt |jj|j|zd||_y)zSeek to specified position into the chunk. Default position is 0 (start of chunk). If the file is not seekable, this will result in an error. r0z cannot seekrN) rr1rrrr RuntimeErrorrseekr)rposwhences r#r7z Chunk.seekfs ;;;< <}}-( ( Q;&C q[&C 7cDNN*  t{{S(!,r)cH|jr td|jS)Nr0)rr1rr&s r#rz Chunk.tellys ;;;< <~~r)cV|jr td|j|jk\ry|dkr|j|jz }||j|jz kDr|j|jz }|jj |}|jt |z|_|j|jk(rS|jrG|jdzr8|jj d}|jt |z|_|S)zRead at most size bytes from the chunk. If size is omitted or negative, read until the end of the chunk. r0r)rr4)rr1rrrrrr)rsizedatadummys r#rz Chunk.read~s ;;;< < >>T^^ + !8>>DNN2D $..4>>1 1>>DNN2Dyy~~d##d)3 >>T^^ + :: NNQ IINN1%E!^^c%j8DN r)c|jr td|jrk |j|jz }|j r|jdzr|dz}|j j|d|j|z|_y|j|jkrWtd|j|jz }|j|}|st|j|jkrVyy#t$rY|wxYw)zSkip the rest of the chunk. If you are not interested in the contents of the chunk, this method should be called so that the file points to the start of the next chunk. r0r4Ni ) rr1rrrrrr7rminrr)rnr>s r#r-z Chunk.skips ;;;< < == NNT^^3::4>>A#5AA q!$!%!!3nnt~~-D$..4>>9:AIIaLE nnt~~-  sA)D D  D N)TTF)r)) __name__ __module__ __qualname__r$r'r+r.r2r7rrr-r)r#rr7s/!4# & .r)r)__doc__warnings _deprecatedrCrrFr)r#rJs.0dXg.vvr)