zzip_entry_fopen, zzip_entry_ffile, zzip_entry_fread, zzip_entry_fclose, zzip_entry_feof — open a file within a zip disk for reading
zzip_entry_fopen function does take an "entry" argument and copies it (or just takes
it over as owner) to a new ZZIP_ENTRY_FILE handle structure. That
structure contains also a zlib buffer for decoding. The
zzip_entry_fopen function does
seek to the file_header of the given "entry" and validates it for the
data buffer following it. We do also prefetch some data from the data
buffer thereby trying to match the disk pagesize for faster access later.
zzip_entry_fread will then read in chunks of pagesizes which is
the size of the internal readahead buffer. If an error occurs then null
zzip_entry_ffile function opens a file found by name, so it does a search into
the zip central directory with
zzip_entry_findfile and whatever
is found first is given to
zzip_entry_fread function reads more bytes into the output buffer specified as
arguments. The return value is null on eof or error, the stdio-like
interface can not distinguish between these so you need to check
zzip_entry_feof for the difference.
zzip_entry_fclose function releases any zlib decoder info needed for decompression
and dumps the ZZIP_ENTRY_FILE struct then.
zzip_entry_feof function allows to distinguish an error from an eof condition.
Actually, if we found an error but we did already reach eof then we
just keep on saying that it was an eof, so the app can just continue.
Copyright (c) 2003,2004 Guido Draheim
All rights reserved,
use under the restrictions of the
Lesser GNU General Public License
or alternatively the restrictions
of the Mozilla Public License 1.1