1zzip_entry_findfile(3) zziplib Function List zzip_entry_findfile(3)
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6 zzip_entry_findfile, zzip_entry_findfirst, zzip_entry_findnext,
7 zzip_entry_free, zzip_entry_findmatch - search for files in the
8 (fseeko) zip central directory
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11 #include <zzip/fseeko.h>
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14 zzip__new__ ZZIP_ENTRY *
15 zzip_entry_findfile(FILE * disk, char *filename,
16 ZZIP_ENTRY * _zzip_restrict entry, zzip_strcmp_fn_t compare)
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18 zzip__new__ ZZIP_ENTRY *
19 zzip_entry_findfirst(FILE * disk)
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21 zzip__new__ ZZIP_ENTRY *
22 zzip_entry_findnext(ZZIP_ENTRY * _zzip_restrict entry)
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24 int
25 zzip_entry_free(ZZIP_ENTRY * entry)
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27 zzip__new__ ZZIP_ENTRY *
28 zzip_entry_findmatch(FILE * disk, char *filespec,
29 ZZIP_ENTRY * _zzip_restrict entry,
30 zzip_fnmatch_fn_t compare, int flags)
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36 The zzip_entry_findfile function is given a filename as an additional
37 argument, to find the disk_entry matching a given filename. The
38 compare-function is usually strcmp or strcasecmp or perhaps strcoll, if
39 null then strcmp is used. - use null as argument for "old"-entry when
40 searching the first matching entry, otherwise the last returned value
41 if you look for other entries with a special "compare" function (if
42 null then a doubled search is rather useless with this variant of
43 _findfile). If no further entry is found then null is returned and any
44 "old"-entry gets already free()d.
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46 The zzip_entry_findfirst function is the first call of all the zip
47 access functions here. It contains the code to find the first entry of
48 the zip central directory. Here we require the stdio handle to
49 represent a real zip file where the disk_trailer is _last_ in the file
50 area, so that its position would be at a fixed offset from the end of
51 the file area if not for the comment field allowed to be of variable
52 length (which needs us to do a little search for the disk_tailer).
53 However, in this simple implementation we disregard any disk_trailer
54 info telling about multidisk archives, so we just return a pointer to
55 the first entry in the zip central directory of that file.
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57 For an actual means, we are going to search backwards from the end of
58 the mmaped block looking for the PK-magic signature of a disk_trailer.
59 If we see one then we check the rootseek value to find the first
60 disk_entry of the root central directory. If we find the correct PK-
61 magic signature of a disk_entry over there then we assume we are done
62 and we are going to return a pointer to that label.
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64 The return value is a pointer to the first zzip_disk_entry being
65 checked to be within the bounds of the file area specified by the
66 arguments. If no disk_trailer was found then null is returned, and
67 likewise we only accept a disk_trailer with a seekvalue that points to
68 a disk_entry and both parts have valid PK-magic parts. Beyond some
69 sanity check we try to catch a common brokeness with zip archives that
70 still allows us to find the start of the zip central directory.
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72 The zzip_entry_findfirst function Returns null on error (errno =
73 EINVAL|ENOMEM|EBADMSG|EBADF|ENOENT)
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75 The zzip_entry_findnext function takes an existing "entry" in the
76 central root directory (e.g. from zzip_entry_findfirst) and moves it to
77 point to the next entry. On error it returns 0, otherwise the old
78 entry. If no further match is found then null is returned and the entry
79 already free()d. If you want to stop searching for matches before that
80 case then please call zzip_entry_free on the cursor struct ZZIP_ENTRY.
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82 the zzip_entry_free function releases the malloc()ed areas needed for
83 zzip_entry, the pointer is invalid afterwards. The zzip_entry_free
84 function has #define synonyms of zzip_entry_findlast(),
85 zzip_entry_findlastfile(), zzip_entry_findlastmatch()
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87 The zzip_entry_findmatch function uses a compare-function with an
88 additional argument and it is called just like fnmatch(3) from POSIX.2
89 AD:1993), i.e. the argument filespec first and the ziplocal filename
90 second with the integer-flags put in as third to the indirect call. If
91 the platform has fnmatch available then null-compare will use that one
92 and otherwise we fall back to mere strcmp, so if you need fnmatch
93 searching then please provide an implementation somewhere else. - use
94 null as argument for "after"-entry when searching the first matching
95 entry, or the last disk_entry return-value to find the next entry
96 matching the given filespec. If no further entry is found then null is
97 returned and any "old"-entry gets already free()d.
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102 Guido Draheim <guidod@gmx.de>
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107 Copyright (c) Guido Draheim, use under copyleft (LGPL,MPL)
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113zziplib 0.13.72 zzip_entry_findfile(3)