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diff --git a/Build/source/libs/zziplib/zziplib-0.13.58/zzip/fseeko.c b/Build/source/libs/zziplib/zziplib-0.13.58/zzip/fseeko.c
new file mode 100644
index 00000000000..2207f5dc981
--- /dev/null
+++ b/Build/source/libs/zziplib/zziplib-0.13.58/zzip/fseeko.c
@@ -0,0 +1,580 @@
+/*
+ * NOTE: this is part of libzzipfseeko (i.e. it is not libzzip).
+ *
+ * These routines are fully independent from the traditional zzip
+ * implementation. They assume a readonly seekable stdio handle
+ * representing a complete zip file. The functions show how to
+ * parse the structure, find files and return a decoded bytestream.
+ *
+ * These routines are a bit simple and really here for documenting
+ * the way to access a zip file. The complexity of zip access comes
+ * from staggered reading of bytes and reposition of a filepointer in
+ * a big archive with lots of files and long compressed datastreams.
+ * Plus varaints of drop-in stdio replacements, obfuscation routines,
+ * auto fileextensions, drop-in dirent replacements, and so on...
+ *
+ * btw, we can _not_ use fgetpos/fsetpos since an fpos_t has no asserted
+ * relation to a linear seek value as specified in zip info headers. In
+ * general it is not a problem if your system has no fseeko/ftello pair
+ * since we can fallback to fseek/ftell which limits the zip disk size
+ * to 2MiBs but the zip-storable seek values are 32bit limited anyway.
+ *
+ * Author:
+ * Guido Draheim <guidod@gmx.de>
+ *
+ * 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
+ */
+
+#define _LARGEFILE_SOURCE 1
+#define _ZZIP_ENTRY_STRUCT 1
+
+#include <zzip/types.h>
+
+#include <assert.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+
+#if defined ZZIP_HAVE_STRING_H
+#include <string.h>
+#elif defined ZZIP_HAVE_STRINGS_H
+#include <strings.h>
+#endif
+
+#include <zlib.h>
+#include <zzip/format.h>
+#include <zzip/fseeko.h>
+#include <zzip/fetch.h>
+#include <zzip/__mmap.h>
+#include <zzip/__fnmatch.h>
+
+#if __STDC_VERSION__+0 > 199900L
+#define ___
+#define ____
+#else
+#define ___ {
+#define ____ }
+#endif
+
+#ifndef ZZIP_HAVE_FSEEKO
+#define fseeko fseek
+#define ftello ftello
+#endif
+
+/* note that the struct zzip_entry inherits the zzip_disk_entry values
+ * and usually carries a copy of its values (in disk format!). To make the
+ * following code more readable, we use a shorthand notation for the
+ * upcast needed in C (not needed in C++) as "disk_(entry)".
+ */
+#ifdef __zzip_entry_extends_zzip_disk_entry
+#define disk_(_entry_) _entry_
+#else
+#define disk_(_entry_) (& (_entry_)->head)
+#endif
+
+/* we try to round all seeks to the pagesize - since we do not use
+ * the sys/mmap interface we have to guess a good value here: */
+#define PAGESIZE 8192
+
+/* ====================================================================== */
+/* helper functions */
+
+/** => zzip_entry_data_offset
+ * This 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.
+ */
+static zzip_off_t
+zzip_entry_fread_file_header (ZZIP_ENTRY* entry,
+ struct zzip_file_header* file_header)
+{
+ if (! entry || ! file_header) return 0;
+ ___ zzip_off_t offset = zzip_disk_entry_fileoffset (disk_(entry));
+ if (0 > offset || offset >= entry->disksize) return 0;
+
+ fseeko (entry->diskfile, offset, SEEK_SET);
+ return (fread (file_header, sizeof(*file_header), 1, entry->diskfile)
+ ? offset+sizeof(*file_header) : 0 ); ____;
+}
+
+/** helper functions for (fseeko) zip access api
+ *
+ * This 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.
+ */
+zzip_off_t
+zzip_entry_data_offset(ZZIP_ENTRY* entry)
+{
+ struct zzip_file_header file_header;
+ if (! entry) return -1;
+ ___ zzip_off_t offset =
+ zzip_entry_fread_file_header (entry, & file_header);
+ if (! offset) return -1;
+ offset += zzip_file_header_sizeof_tails (& file_header);
+ fseeko (entry->diskfile, offset, SEEK_SET);
+ return offset; ____;
+}
+
+/** => zzip_entry_data_offset
+ * This 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.
+ */
+zzip__new__ char*
+zzip_entry_strdup_name(ZZIP_ENTRY* entry)
+{
+ if (! entry) return 0;
+
+ ___ zzip_size_t len;
+ if ((len = zzip_disk_entry_namlen (disk_(entry)))) {
+ char* name = malloc (len+1);
+ if (! name) return 0;
+ memcpy (name, entry->tail, len);
+ name[len] = '\0';
+ return name;
+ }
+ ___ auto struct zzip_file_header header;
+ if (zzip_entry_fread_file_header (entry, &header)
+ && ( len = zzip_file_header_namlen(&header) )) {
+ char* name = malloc (len+1);
+ if (! name) return 0;
+ fread (name, 1, len, entry->diskfile);
+ name[len] = '\0';
+ return name;
+ }
+ return 0;
+ ____;____;
+}
+
+static int
+prescan_entry(ZZIP_ENTRY* entry)
+{
+ assert (entry);
+ ___ zzip_off_t tailsize = zzip_disk_entry_sizeof_tails (disk_(entry));
+ if (tailsize+1 > entry->tailalloc) {
+ char* newtail = realloc (entry->tail, tailsize+1);
+ if (! newtail) return ENOMEM;
+ entry->tail = newtail;
+ entry->tailalloc = tailsize+1;
+ }
+ fread (entry->tail, 1, tailsize, entry->diskfile);
+ /* name + comment + extras */
+ return 0; ____;
+}
+
+static void
+prescan_clear(ZZIP_ENTRY* entry)
+{
+ assert (entry);
+ if (entry->tail) free (entry->tail);
+ entry->tail = 0; entry->tailalloc = 0;
+}
+
+/* ====================================================================== */
+
+/** => zzip_entry_findfile
+ *
+ * This 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.
+ *
+ * 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.
+ */
+zzip__new__ ZZIP_ENTRY*
+zzip_entry_findfirst(FILE* disk)
+{
+ if (! disk) return 0;
+ fseeko (disk, 0, SEEK_END);
+ ___ zzip_off_t disksize = ftello (disk);
+ if (disksize < (zzip_off_t) sizeof(struct zzip_disk_trailer)) return 0;
+ /* we read out chunks of 8 KiB in the hope to match disk granularity */
+ ___ zzip_off_t pagesize = PAGESIZE; /* getpagesize() */
+ ___ ZZIP_ENTRY* entry = malloc (sizeof(*entry)); if (! entry) return 0;
+ ___ unsigned char* buffer = malloc (pagesize); if (! buffer) goto nomem;
+
+ assert (pagesize/2 > (zzip_off_t) sizeof (struct zzip_disk_trailer));
+ /* at each step, we will fread a pagesize block which overlaps with the
+ * previous read by means of pagesize/2 step at the end of the while(1) */
+ ___ zzip_off_t mapoffs = disksize &~ (pagesize-1);
+ ___ zzip_off_t mapsize = disksize - mapoffs;
+ if (mapoffs && mapsize < pagesize/2) {
+ mapoffs -= pagesize/2; mapsize += pagesize/2; }
+ while(1) {
+ fseeko (disk, mapoffs, SEEK_SET);
+ fread (buffer, 1, mapsize, disk);
+ ___ unsigned char* p =
+ buffer + mapsize - sizeof(struct zzip_disk_trailer);
+ for (; p >= buffer ; p--)
+ {
+ zzip_off_t root; /* (struct zzip_disk_entry*) */
+ if (zzip_disk_trailer_check_magic(p)) {
+ root = zzip_disk_trailer_rootseek (
+ (struct zzip_disk_trailer*)p);
+ if (root > disksize - (long)sizeof(struct zzip_disk_trailer)) {
+ /* first disk_entry is after the disk_trailer? can't be! */
+ zzip_off_t rootsize = zzip_disk_trailer_rootsize (
+ (struct zzip_disk_trailer*)p);
+ if (rootsize > mapoffs) continue;
+ /* a common brokeness that can be fixed: we just assume the
+ * central directory was written directly before : */
+ root = mapoffs - rootsize;
+ }
+ } else if (zzip_disk64_trailer_check_magic(p)) {
+ if (sizeof(zzip_off_t) < 8) return 0;
+ root = zzip_disk64_trailer_rootseek (
+ (struct zzip_disk64_trailer*)p);
+ } else continue;
+
+ assert (0 <= root && root < mapsize);
+ fseeko (disk, root, SEEK_SET);
+ fread (disk_(entry), 1, sizeof(*disk_(entry)), disk);
+ if (zzip_disk_entry_check_magic(entry)) {
+ free (buffer);
+ entry->headseek = root;
+ entry->diskfile = disk;
+ entry->disksize = disksize;
+ if (prescan_entry(entry)) goto nomem;
+ return entry;
+ }
+ } ____;
+ if (! mapoffs) break; assert (mapsize >= pagesize/2);
+ mapoffs -= pagesize/2; /* mapsize += pagesize/2; */
+ mapsize = pagesize; /* if (mapsize > pagesize) ... */
+ if (disksize - mapoffs > 64*1024) break;
+ }
+ free (buffer);
+ nomem:
+ free (entry); ____;____;____;____;____;____;
+ return 0;
+}
+
+/** => zzip_entry_findfile
+ *
+ * This 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
+ * => zzip_entry_free on the cursor struct ZZIP_ENTRY.
+ */
+zzip__new__ ZZIP_ENTRY*
+zzip_entry_findnext(ZZIP_ENTRY* _zzip_restrict entry)
+{
+ if (! entry) return entry;
+ if (! zzip_disk_entry_check_magic (entry)) goto err;
+ ___ zzip_off_t seek =
+ entry->headseek + zzip_disk_entry_sizeto_end (disk_(entry));
+ if (seek + (zzip_off_t) sizeof(*disk_(entry)) > entry->disksize) goto err;
+
+ fseeko (entry->diskfile, seek, SEEK_SET);
+ fread (disk_(entry), 1, sizeof(*disk_(entry)), entry->diskfile);
+ entry->headseek = seek;
+ if (! zzip_disk_entry_check_magic (entry)) goto err;
+ if (prescan_entry(entry)) goto err;
+ return entry;
+ err:
+ zzip_entry_free (entry);
+ return 0; ____;
+}
+
+/** => zzip_entry_findfile
+ * this function releases the malloc()ed areas needed for zzip_entry, the
+ * pointer is invalid afterwards. This function has #define synonyms of
+ * zzip_entry_findlast(), zzip_entry_findlastfile(), zzip_entry_findlastmatch()
+ */
+int
+zzip_entry_free(ZZIP_ENTRY* entry)
+{
+ if (! entry) return 0;
+ prescan_clear (entry);
+ free (entry);
+ return 1;
+}
+
+/** search for files in the (fseeko) zip central directory
+ *
+ * This 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.
+ */
+zzip__new__ ZZIP_ENTRY*
+zzip_entry_findfile(FILE* disk, char* filename,
+ ZZIP_ENTRY* _zzip_restrict entry,
+ zzip_strcmp_fn_t compare)
+{
+ if (! filename || ! disk) return 0;
+ entry = ( ! entry ) ? zzip_entry_findfirst (disk)
+ : zzip_entry_findnext (entry);
+ if (! compare) compare = (zzip_strcmp_fn_t)(strcmp);
+
+ for (; entry ; entry = zzip_entry_findnext (entry))
+ { /* filenames within zip files are often not null-terminated! */
+ char* realname = zzip_entry_strdup_name (entry);
+ if (! realname) continue;
+ if (! compare (filename, realname)) {
+ free (realname); return entry;
+ } else {
+ free (realname); continue;
+ }
+ }
+ return 0;
+}
+
+#ifdef ZZIP_HAVE_FNMATCH_H
+#define _zzip_fnmatch fnmatch
+# ifdef FNM_CASEFOLD
+# define _zzip_fnmatch_CASEFOLD FNM_CASEFOLD
+# else
+# define _zzip_fnmatch_CASEFOLD 0
+# endif
+#else
+# define _zzip_fnmatch_CASEFOLD 0
+/* if your system does not have fnmatch, we fall back to strcmp: */
+static int _zzip_fnmatch(char* pattern, char* string, int flags)
+{
+ puts ("<zzip:strcmp>");
+ return strcmp (pattern, string);
+}
+#endif
+
+/** => zzip_entry_findfile
+ *
+ * This 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.
+ */
+zzip__new__ ZZIP_ENTRY*
+zzip_entry_findmatch(FILE* disk, char* filespec,
+ ZZIP_ENTRY* _zzip_restrict entry,
+ zzip_fnmatch_fn_t compare, int flags)
+{
+ if (! filespec || ! disk) return 0;
+ entry = ( ! entry ) ? zzip_entry_findfirst (disk)
+ : zzip_entry_findnext (entry);
+ if (! compare) compare = (zzip_fnmatch_fn_t) _zzip_fnmatch;
+
+ for (; entry ; entry = zzip_entry_findnext (entry))
+ { /* filenames within zip files are often not null-terminated! */
+ char* realname = zzip_entry_strdup_name (entry);
+ if (! realname) continue;
+ if (! compare (filespec, realname, flags)) {
+ free (realname); return entry;
+ } else {
+ free (realname); continue;
+ }
+ }
+ return 0;
+}
+
+/* ====================================================================== */
+
+/**
+ * typedef struct zzip_disk_file ZZIP_ENTRY_FILE;
+ */
+struct zzip_entry_file /* : zzip_file_header */
+{
+ struct zzip_file_header header; /* fopen detected header */
+ ZZIP_ENTRY* entry; /* fopen entry */
+ zzip_off_t data; /* for stored blocks */
+ zzip_size_t avail; /* memorized for checks on EOF */
+ zzip_size_t compressed; /* compressed flag and datasize */
+ zzip_size_t dataoff; /* offset from data start */
+ z_stream zlib; /* for inflated blocks */
+ unsigned char buffer[PAGESIZE]; /* work buffer for inflate algorithm */
+};
+
+/** open a file within a zip disk for reading
+ *
+ * This 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. This 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 => 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
+ * is returned.
+ */
+zzip__new__ ZZIP_ENTRY_FILE*
+zzip_entry_fopen (ZZIP_ENTRY* entry, int takeover)
+{
+ if (! entry) return 0;
+ if (! takeover) {
+ ZZIP_ENTRY* found = malloc (sizeof(*entry));
+ if (! found) return 0;
+ memcpy (found, entry, sizeof(*entry)); /* prescan_copy */
+ found->tail = malloc (found->tailalloc);
+ if (! found->tail) { free (found); return 0; }
+ memcpy (found->tail, entry->tail, entry->tailalloc);
+ entry = found;
+ }
+ ___ ZZIP_ENTRY_FILE* file = malloc(sizeof(*file));
+ if (! file) goto fail1;
+ file->entry = entry;
+ if (! zzip_entry_fread_file_header (entry, &file->header))
+ goto fail2;
+ file->avail = zzip_file_header_usize (&file->header);
+ file->data = zzip_entry_data_offset (entry);
+ file->dataoff = 0;
+
+ if (! file->avail || zzip_file_header_data_stored (&file->header))
+ { file->compressed = 0; return file; }
+
+ file->compressed = zzip_file_header_csize (&file->header);
+ file->zlib.opaque = 0;
+ file->zlib.zalloc = Z_NULL;
+ file->zlib.zfree = Z_NULL;
+
+ ___ zzip_off_t seek = file->data;
+ seek += sizeof(file->buffer); seek -= seek & (sizeof(file->buffer)-1);
+ assert (file->data < seek); /* pre-read to next PAGESIZE boundary... */
+ fseeko (file->entry->diskfile, file->data + file->dataoff, SEEK_SET);
+ file->zlib.next_in = file->buffer;
+ file->zlib.avail_in = fread (file->buffer, 1, seek - file->data,
+ file->entry->diskfile);
+ file->dataoff += file->zlib.avail_in; ____;
+
+ if (! zzip_file_header_data_deflated (&file->header)
+ || inflateInit2 (& file->zlib, -MAX_WBITS) != Z_OK) goto fail2;
+
+ return file;
+ fail2:
+ free (file);
+ fail1:
+ zzip_entry_free (entry);
+ return 0; ____;
+}
+
+/** => zzip_entry_fopen
+ *
+ * This 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_fopen
+ */
+zzip__new__ ZZIP_ENTRY_FILE*
+zzip_entry_ffile (FILE* disk, char* filename)
+{
+ ZZIP_ENTRY* entry = zzip_entry_findfile (disk, filename, 0, 0);
+ if (! entry) return 0;
+ return zzip_entry_fopen (entry, 1);
+}
+
+
+/** => zzip_entry_fopen
+ *
+ * This 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 => zzip_entry_feof for the difference.
+ */
+zzip_size_t
+zzip_entry_fread (void* ptr, zzip_size_t sized, zzip_size_t nmemb,
+ ZZIP_ENTRY_FILE* file)
+{
+ if (! file) return 0;
+ ___ zzip_size_t size = sized*nmemb;
+ if (! file->compressed) {
+ if (size > file->avail) size = file->avail;
+ fread (ptr, 1, size, file->entry->diskfile);
+ file->dataoff += size;
+ file->avail -= size;
+ return size;
+ }
+
+ file->zlib.avail_out = size;
+ file->zlib.next_out = ptr;
+ ___ zzip_size_t total_old = file->zlib.total_out;
+ while (1) {
+ if (! file->zlib.avail_in) {
+ size = file->compressed - file->dataoff;
+ if (size > sizeof(file->buffer)) size = sizeof(file->buffer);
+ /* fseek (file->data + file->dataoff, file->entry->diskfile); */
+ file->zlib.avail_in = fread (file->buffer, 1, size,
+ file->entry->diskfile);
+ file->zlib.next_in = file->buffer;
+ file->dataoff += file->zlib.avail_in;
+ }
+ if (! file->zlib.avail_in) return 0;
+
+ ___ int err = inflate (& file->zlib, Z_NO_FLUSH);
+ if (err == Z_STREAM_END)
+ file->avail = 0;
+ else if (err == Z_OK)
+ file->avail -= file->zlib.total_out - total_old;
+ else
+ return 0;
+ ____;
+ if (file->zlib.avail_out && ! file->zlib.avail_in) continue;
+ return file->zlib.total_out - total_old;
+ }____;____;
+}
+
+/** => zzip_entry_fopen
+ * This function releases any zlib decoder info needed for decompression
+ * and dumps the ZZIP_ENTRY_FILE struct then.
+ */
+int
+zzip_entry_fclose (ZZIP_ENTRY_FILE* file)
+{
+ if (! file) return 0;
+ if (file->compressed)
+ inflateEnd (& file->zlib);
+ zzip_entry_free (file->entry);
+ free (file);
+ return 0;
+}
+
+/** => zzip_entry_fopen
+ *
+ * This 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.
+ */
+int
+zzip_entry_feof (ZZIP_ENTRY_FILE* file)
+{
+ return ! file || ! file->avail;
+}