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ZZIP_DISK_FINDFILE(3)	     zziplib Function List	 ZZIP_DISK_FINDFILE(3)

NAME
       zzip_disk_findfile, zzip_disk_findfirst,	zzip_disk_findnext,
       zzip_disk_findmatch - search for	files in the (mmapped) zip central
       directory

SYNOPSIS
       #include	<zzip/mmapped.h>

       struct zzip_disk_entry *
						   zzip_disk_findfile((ZZIP_DISK * disk, char *filename, struct	zzip_disk_entry	*after,	zzip_strcmp_fn_t compare));

       struct zzip_disk_entry *	zzip_disk_findfirst((ZZIP_DISK * disk));

       struct zzip_disk_entry *
						   zzip_disk_findnext((ZZIP_DISK * disk, struct	zzip_disk_entry	*entry));

       struct zzip_disk_entry *
						    zzip_disk_findmatch((ZZIP_DISK * disk, char	*filespec, struct zzip_disk_entry *after, zzip_fnmatch_fn_t compare, int flags));

DESCRIPTION
       The zzip_disk_findfile function is given	a filename as an additional
       argument, to find the disk_entry	matching a given filename. The
       compare-function	is usually strcmp or strcasecmp	or perhaps strcoll, if
       null then strcmp	is used. - use null as argument	for "after"-entry when
       searching the first matching entry, otherwise the last returned value
       if you look for other entries with a special "compare" function (if
       null then a doubled search is rather useless with this variant of
       _findfile).

       The zzip_disk_findfirst function	is the first call of all the zip
       access functions	here. It contains the code to find the first entry of
       the zip central directory. Here we require the mmapped block to
       represent a real	zip file where the disk_trailer	is _last_ in the file
       area, so	that its position would	be at a	fixed offset from the end of
       the file	area if	not for	the comment field allowed to be	of variable
       length (which needs us to do a little search for	the disk_tailer).
       However,	in this	simple implementation we disregard any disk_trailer
       info telling about multidisk archives, so we just return	a pointer to
       the zip central directory.

       For an actual means, we are going to search backwards from the end of
       the mmaped block	looking	for the	PK-magic signature of a	disk_trailer.
       If we see one then we check the rootseek	value to find the first
       disk_entry of the root central directory. If we find the	correct
       PK-magic	signature of a disk_entry over there then we assume we are
       done and	we are going to	return a pointer to that label.

       The return value	is a pointer to	the first zzip_disk_entry being
       checked to be within the	bounds of the file area	specified by the
       arguments. If no	disk_trailer was found then null is returned, and
       likewise	we only	accept a disk_trailer with a seekvalue that points to
       a disk_entry and	both parts have	valid PK-magic parts. Beyond some
       sanity check we try to catch a common brokeness with zip	archives that
       still allows us to find the start of the	zip central directory.

       The zzip_disk_findnext function takes an	existing disk_entry in the
       central root directory (e.g. from zzip_disk_findfirst) and returns the
       next entry within in the	given bounds of	the mmapped file area.

       The zzip_disk_findmatch function	uses a compare-function	with an
       additional argument and it is called just like fnmatch(3) from POSIX.2
       AD:1993), i.e. the argument filespec first and the ziplocal filename
       second with the integer-flags put in as third to	the indirect call. If
       the platform has	fnmatch	available then null-compare will use that one
       and otherwise we	fall back to mere strcmp, so if	you need fnmatch
       searching then please provide an	implementation somewhere else. - use
       null as argument	for "after"-entry when searching the first matching
       entry, or the last disk_entry return-value to find the next entry
       matching	the given filespec.

AUTHOR
       o   Guido Draheim <guidod@gmx.de>

COPYRIGHT
       Copyright (c) 2003,2004,2006 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

zziplib				    0.13.62		 ZZIP_DISK_FINDFILE(3)

NAME | SYNOPSIS | DESCRIPTION | AUTHOR | COPYRIGHT

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