<html><head><title>zziplib Library Functions</title>
</head><body>
<h2>zziplib Library Functions</h2><p>Version 0.13.62</p><p><big><b><code>#include <zzip/fseeko.h></code></b></big></p><table width="100%"><tr><td valign="top"><code><b><code><a href="#zzip_entry_fopen">zzip_entry_fopen</a></code></b>(ZZIP_ENTRY * entry, int takeover)
: zzip__new__ ZZIP_ENTRY_FILE *
</code></td></tr><tr><td valign="top"><code><b><code><a href="#zzip_entry_ffile">zzip_entry_ffile</a></code></b>(FILE * disk, char *filename)
: zzip__new__ ZZIP_ENTRY_FILE *
</code></td></tr><tr><td valign="top"><code><b><code><a href="#zzip_entry_fread">zzip_entry_fread</a></code></b>(void *ptr, zzip_size_t sized, zzip_size_t nmemb,
ZZIP_ENTRY_FILE * file)
: zzip_size_t
</code></td></tr><tr><td valign="top"><code><b><code><a href="#zzip_entry_fclose">zzip_entry_fclose</a></code></b>(ZZIP_ENTRY_FILE * file)
: int
</code></td></tr><tr><td valign="top"><code><b><code><a href="#zzip_entry_feof">zzip_entry_feof</a></code></b>(ZZIP_ENTRY_FILE * file)
: int
</code></td></tr><tr><td valign="top"><code><b><code><a href="#zzip_entry_data_offset">zzip_entry_data_offset</a></code></b>(ZZIP_ENTRY * entry)
: zzip_off_t
</code></td></tr><tr><td valign="top"><code><b><code><a href="#zzip_entry_fread_file_header">zzip_entry_fread_file_header</a></code></b>(ZZIP_ENTRY * entry,
struct zzip_file_header *file_header)
: static zzip_off_t
</code></td></tr><tr><td valign="top"><code><b><code><a href="#zzip_entry_strdup_name">zzip_entry_strdup_name</a></code></b>(ZZIP_ENTRY * entry)
: zzip__new__ char *
</code></td></tr><tr><td valign="top"><code><b><code><a href="#zzip_entry_findfile">zzip_entry_findfile</a></code></b>(FILE * disk, char *filename,
ZZIP_ENTRY * _zzip_restrict entry, zzip_strcmp_fn_t compare)
: zzip__new__ ZZIP_ENTRY *
</code></td></tr><tr><td valign="top"><code><b><code><a href="#zzip_entry_findfirst">zzip_entry_findfirst</a></code></b>(FILE * disk)
: zzip__new__ ZZIP_ENTRY *
</code></td></tr><tr><td valign="top"><code><b><code><a href="#zzip_entry_findnext">zzip_entry_findnext</a></code></b>(ZZIP_ENTRY * _zzip_restrict entry)
: zzip__new__ ZZIP_ENTRY *
</code></td></tr><tr><td valign="top"><code><b><code><a href="#zzip_entry_free">zzip_entry_free</a></code></b>(ZZIP_ENTRY * entry)
: int
</code></td></tr><tr><td valign="top"><code><b><code><a href="#zzip_entry_findmatch">zzip_entry_findmatch</a></code></b>(FILE * disk, char *filespec,
ZZIP_ENTRY * _zzip_restrict entry,
zzip_fnmatch_fn_t compare, int flags)
: zzip__new__ ZZIP_ENTRY *
</code></td></tr></table><h3>Documentation</h3><dl><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"><tr><td valign="top"><code><b><a name="zzip_entry_fopen">zzip_entry_fopen</a></b>(ZZIP_ENTRY * entry, int takeover)
: zzip__new__ ZZIP_ENTRY_FILE *
</code></td></tr><tr><td valign="top"><code><b><a name="zzip_entry_ffile">zzip_entry_ffile</a></b>(FILE * disk, char *filename)
: zzip__new__ ZZIP_ENTRY_FILE *
</code></td></tr><tr><td valign="top"><code><b><a name="zzip_entry_fread">zzip_entry_fread</a></b>(void *ptr, zzip_size_t sized, zzip_size_t nmemb,
ZZIP_ENTRY_FILE * file)
: zzip_size_t
</code></td></tr><tr><td valign="top"><code><b><a name="zzip_entry_fclose">zzip_entry_fclose</a></b>(ZZIP_ENTRY_FILE * file)
: int
</code></td></tr><tr><td valign="top"><code><b><a name="zzip_entry_feof">zzip_entry_feof</a></b>(ZZIP_ENTRY_FILE * file)
: int
</code></td></tr></table></dt><dd><table width="100%"><tr><td valign="top"><table border="0" width="100%" cellpadding="0" cellspacing="0"><td> <em> open a file within a zip disk for reading</em> </td><td align="right"> <em><small>zzip/fseeko.c</small></em></td></table><p>
The <code>zzip_entry_fopen</code> 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 <code>zzip_entry_fopen</code> 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.
The <code><a href="#zzip_entry_fread">zzip_entry_fread</a></code> will then read in chunks of pagesizes which is
the size of the internal readahead buffer. If an error occurs then null
is returned.
</p>
</td></tr><tr><td valign="top"><p>
The <code>zzip_entry_ffile</code> function opens a file found by name, so it does a search into
the zip central directory with <code><a href="#zzip_entry_findfile">zzip_entry_findfile</a></code> and whatever
is found first is given to <code><a href="#zzip_entry_fopen">zzip_entry_fopen</a></code>
</p>
</td></tr><tr><td valign="top"><p>
The <code>zzip_entry_fread</code> 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
with <code><a href="#zzip_entry_feof">zzip_entry_feof</a></code> for the difference.
</p>
</td></tr><tr><td valign="top"><p> The <code>zzip_entry_fclose</code> function releases any zlib decoder info needed for decompression
and dumps the ZZIP_ENTRY_FILE struct then.
</p>
</td></tr><tr><td valign="top"><p>
The <code>zzip_entry_feof</code> 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.
</p>
</td></tr></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"><tr><td valign="top"><code><b><a name="zzip_entry_data_offset">zzip_entry_data_offset</a></b>(ZZIP_ENTRY * entry)
: zzip_off_t
</code></td></tr><tr><td valign="top"><code><b><a name="zzip_entry_fread_file_header">zzip_entry_fread_file_header</a></b>(ZZIP_ENTRY * entry,
struct zzip_file_header *file_header)
: static zzip_off_t
</code></td></tr><tr><td valign="top"><code><b><a name="zzip_entry_strdup_name">zzip_entry_strdup_name</a></b>(ZZIP_ENTRY * entry)
: zzip__new__ char *
</code></td></tr></table></dt><dd><table width="100%"><tr><td valign="top"><table border="0" width="100%" cellpadding="0" cellspacing="0"><td> <em> helper functions for (fseeko) zip access api</em> </td><td align="right"> <em><small>zzip/fseeko.c</small></em></td></table><p>
The <code>zzip_entry_data_offset</code> functions returns the seekval offset of the data portion of the
file referenced by the given zzip_entry. It requires an intermediate
check of the file_header structure (i.e. it reads it from disk). After
this call, the contained diskfile readposition is already set to the
data_offset returned here. On error -1 is returned.
</p>
</td></tr><tr><td valign="top"><p> The <code>zzip_entry_fread_file_header</code> functions read the correspoding struct zzip_file_header from
the zip disk of the given "entry". The returned off_t points to the
end of the file_header where the current fseek pointer has stopped.
This is used to immediatly parse out any filename/extras block following
the file_header. The return value is null on error.
</p>
</td></tr><tr><td valign="top"><p> The <code>zzip_entry_strdup_name</code> function is a big helper despite its little name: in a zip file the
encoded filenames are usually NOT zero-terminated but for common usage
with libc we need it that way. Secondly, the filename SHOULD be present
in the zip central directory but if not then we fallback to the filename
given in the file_header of each compressed data portion.
</p>
</td></tr></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"></table></dt><dd><table width="100%"></table></dd><dt><table width="100%"><tr><td valign="top"><code><b><a name="zzip_entry_findfile">zzip_entry_findfile</a></b>(FILE * disk, char *filename,
ZZIP_ENTRY * _zzip_restrict entry, zzip_strcmp_fn_t compare)
: zzip__new__ ZZIP_ENTRY *
</code></td></tr><tr><td valign="top"><code><b><a name="zzip_entry_findfirst">zzip_entry_findfirst</a></b>(FILE * disk)
: zzip__new__ ZZIP_ENTRY *
</code></td></tr><tr><td valign="top"><code><b><a name="zzip_entry_findnext">zzip_entry_findnext</a></b>(ZZIP_ENTRY * _zzip_restrict entry)
: zzip__new__ ZZIP_ENTRY *
</code></td></tr><tr><td valign="top"><code><b><a name="zzip_entry_free">zzip_entry_free</a></b>(ZZIP_ENTRY * entry)
: int
</code></td></tr><tr><td valign="top"><code><b><a name="zzip_entry_findmatch">zzip_entry_findmatch</a></b>(FILE * disk, char *filespec,
ZZIP_ENTRY * _zzip_restrict entry,
zzip_fnmatch_fn_t compare, int flags)
: zzip__new__ ZZIP_ENTRY *
</code></td></tr></table></dt><dd><table width="100%"><tr><td valign="top"><table border="0" width="100%" cellpadding="0" cellspacing="0"><td> <em> search for files in the (fseeko) zip central directory</em> </td><td align="right"> <em><small>zzip/fseeko.c</small></em></td></table><p>
The <code>zzip_entry_findfile</code> 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 "old"-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). If no further entry is
found then null is returned and any "old"-entry gets already free()d.
</p>
</td></tr><tr><td valign="top"><p>
The <code>zzip_entry_findfirst</code> 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 stdio handle 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 first entry in the zip central directory of that file.
</p><p>
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.
</p><p>
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.
</p>
</td></tr><tr><td valign="top"><p>
The <code>zzip_entry_findnext</code> function takes an existing "entry" in the central root directory
(e.g. from zzip_entry_findfirst) and moves it to point to the next entry.
On error it returns 0, otherwise the old entry. If no further match is
found then null is returned and the entry already free()d. If you want
to stop searching for matches before that case then please call
<code><a href="#zzip_entry_free">zzip_entry_free</a></code> on the cursor struct ZZIP_ENTRY.
</p>
</td></tr><tr><td valign="top"><p> the <code>zzip_entry_free</code> function releases the malloc()ed areas needed for zzip_entry, the
pointer is invalid afterwards. The <code>zzip_entry_free</code> function has #define synonyms of
zzip_entry_findlast(), zzip_entry_findlastfile(), zzip_entry_findlastmatch()
</p>
</td></tr><tr><td valign="top"><p>
The <code>zzip_entry_findmatch</code> 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. If no further entry is
found then null is returned and any "old"-entry gets already free()d.
</p>
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