/* unzip.c -- IO for uncompress .zip files using zlib
   Version 1.01e, February 12th, 2005

   Copyright (C) 1998-2005 Gilles Vollant

   Read unzip.h for more info
*/

/* Decryption code comes from crypt.c by Info-ZIP but has been greatly reduced in terms of
compatibility with older software. The following is from the original crypt.c. Code
woven in by Terry Thorsen 1/2003.
*/
/*
  Copyright (c) 1990-2000 Info-ZIP.  All rights reserved.

  See the accompanying file LICENSE, version 2000-Apr-09 or later
  (the contents of which are also included in zip.h) for terms of use.
  If, for some reason, all these files are missing, the Info-ZIP license
  also may be found at:  ftp://ftp.info-zip.org/pub/infozip/license.html
*/
/*
  crypt.c (full version) by Info-ZIP.      Last revised:  [see crypt.h]

  The encryption/decryption parts of this source code (as opposed to the
  non-echoing password parts) were originally written in Europe.  The
  whole source package can be freely distributed, including from the USA.
  (Prior to January 2000, re-export from the US was a violation of US law.)
 */

/*
  This encryption code is a direct transcription of the algorithm from
  Roger Schlafly, described by Phil Katz in the file appnote.txt.  This
  file (appnote.txt) is distributed with the PKZIP program (even in the
  version without encryption capabilities).
 */


#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "zlib.h"
#include "unzip.h"

#ifdef STDC
#  include <stddef.h>
#  include <string.h>
#  include <stdlib.h>
#endif
#ifdef NO_ERRNO_H
    extern int errno;
#else
#   include <errno.h>
#endif


#ifndef local
#  define local static
#endif
/* compile with -Dlocal if your debugger can't find static symbols */


#ifndef CASESENSITIVITYDEFAULT_NO
#  if !defined(unix) && !defined(CASESENSITIVITYDEFAULT_YES)
#    define CASESENSITIVITYDEFAULT_NO
#  endif
#endif


#ifndef UNZ_BUFSIZE
#define UNZ_BUFSIZE (16384)
#endif

#ifndef UNZ_MAXFILENAMEINZIP
#define UNZ_MAXFILENAMEINZIP (256)
#endif

#ifndef ALLOC
# define ALLOC(size) (malloc(size))
#endif
#ifndef TRYFREE
# define TRYFREE(p) {if (p) free(p);}
#endif

#define SIZECENTRALDIRITEM (0x2e)
#define SIZEZIPLOCALHEADER (0x1e)




const char unz_copyright[] =
   " unzip 1.01 Copyright 1998-2004 Gilles Vollant - http://www.winimage.com/zLibDll";

/* unz_file_info_interntal contain internal info about a file in zipfile*/
typedef struct unz_file_info_internal_s
{
    uLong offset_curfile;/* relative offset of local header 4 bytes */
} unz_file_info_internal;


/* file_in_zip_read_info_s contain internal information about a file in zipfile,
    when reading and decompress it */
typedef struct
{
    char  *read_buffer;         /* internal buffer for compressed data */
    z_stream stream;            /* zLib stream structure for inflate */

    uLong pos_in_zipfile;       /* position in byte on the zipfile, for fseek*/
    uLong stream_initialised;   /* flag set if stream structure is initialised*/

    uLong offset_local_extrafield;/* offset of the local extra field */
    uInt  size_local_extrafield;/* size of the local extra field */
    uLong pos_local_extrafield;   /* position in the local extra field in read*/

    uLong crc32;                /* crc32 of all data uncompressed */
    uLong crc32_wait;           /* crc32 we must obtain after decompress all */
    uLong rest_read_compressed; /* number of byte to be decompressed */
    uLong rest_read_uncompressed;/*number of byte to be obtained after decomp*/
    zlib_filefunc_def z_filefunc;
    voidpf filestream;        /* io structore of the zipfile */
    uLong compression_method;   /* compression method (0==store) */
    uLong byte_before_the_zipfile;/* byte before the zipfile, (>0 for sfx)*/
    int   raw;
} file_in_zip_read_info_s;


/* unz_s contain internal information about the zipfile
*/
typedef struct
{
    zlib_filefunc_def z_filefunc;
    voidpf filestream;        /* io structore of the zipfile */
    unz_global_info gi;       /* public global information */
    uLong byte_before_the_zipfile;/* byte before the zipfile, (>0 for sfx)*/
    uLong num_file;             /* number of the current file in the zipfile*/
    uLong pos_in_central_dir;   /* pos of the current file in the central dir*/
    uLong current_file_ok;      /* flag about the usability of the current file*/
    uLong central_pos;          /* position of the beginning of the central dir*/

    uLong size_central_dir;     /* size of the central directory  */
    uLong offset_central_dir;   /* offset of start of central directory with
                                   respect to the starting disk number */

    unz_file_info cur_file_info; /* public info about the current file in zip*/
    unz_file_info_internal cur_file_info_internal; /* private info about it*/
    file_in_zip_read_info_s* pfile_in_zip_read; /* structure about the current
                                        file if we are decompressing it */
    int encrypted;
#    ifndef NOUNCRYPT
    unsigned long keys[3];     /* keys defining the pseudo-random sequence */
    const unsigned long* pcrc_32_tab;
#    endif
} unz_s;


#ifndef NOUNCRYPT
#include "crypt.h"
#endif

/* ===========================================================================
     Read a byte from a gz_stream; update next_in and avail_in. Return EOF
   for end of file.
   IN assertion: the stream s has been sucessfully opened for reading.
*/


local int unzlocal_getByte OF((
    const zlib_filefunc_def* pzlib_filefunc_def,
    voidpf filestream,
    int *pi));

local int unzlocal_getByte(pzlib_filefunc_def,filestream,pi)
    const zlib_filefunc_def* pzlib_filefunc_def;
    voidpf filestream;
    int *pi;
{
    unsigned char c;
    int err = (int)ZREAD(*pzlib_filefunc_def,filestream,&c,1);
    if (err==1)
    {
        *pi = (int)c;
        return UNZ_OK;
    }
    else
    {
        if (ZERROR(*pzlib_filefunc_def,filestream))
            return UNZ_ERRNO;
        else
            return UNZ_EOF;
    }
}


/* ===========================================================================
   Reads a long in LSB order from the given gz_stream. Sets
*/
local int unzlocal_getShort OF((
    const zlib_filefunc_def* pzlib_filefunc_def,
    voidpf filestream,
    uLong *pX));

local int unzlocal_getShort (pzlib_filefunc_def,filestream,pX)
    const zlib_filefunc_def* pzlib_filefunc_def;
    voidpf filestream;
    uLong *pX;
{
    uLong x ;
    int i;
    int err;

    err = unzlocal_getByte(pzlib_filefunc_def,filestream,&i);
    x = (uLong)i;

    if (err==UNZ_OK)
        err = unzlocal_getByte(pzlib_filefunc_def,filestream,&i);
    x += ((uLong)i)<<8;

    if (err==UNZ_OK)
        *pX = x;
    else
        *pX = 0;
    return err;
}

local int unzlocal_getLong OF((
    const zlib_filefunc_def* pzlib_filefunc_def,
    voidpf filestream,
    uLong *pX));

local int unzlocal_getLong (pzlib_filefunc_def,filestream,pX)
    const zlib_filefunc_def* pzlib_filefunc_def;
    voidpf filestream;
    uLong *pX;
{
    uLong x ;
    int i;
    int err;

    err = unzlocal_getByte(pzlib_filefunc_def,filestream,&i);
    x = (uLong)i;

    if (err==UNZ_OK)
        err = unzlocal_getByte(pzlib_filefunc_def,filestream,&i);
    x += ((uLong)i)<<8;

    if (err==UNZ_OK)
        err = unzlocal_getByte(pzlib_filefunc_def,filestream,&i);
    x += ((uLong)i)<<16;

    if (err==UNZ_OK)
        err = unzlocal_getByte(pzlib_filefunc_def,filestream,&i);
    x += ((uLong)i)<<24;

    if (err==UNZ_OK)
        *pX = x;
    else
        *pX = 0;
    return err;
}


/* My own strcmpi / strcasecmp */
local int strcmpcasenosensitive_internal (fileName1,fileName2)
    const char* fileName1;
    const char* fileName2;
{
    for (;;)
    {
        char c1=*(fileName1++);
        char c2=*(fileName2++);
        if ((c1>='a') && (c1<='z'))
            c1 -= 0x20;
        if ((c2>='a') && (c2<='z'))
            c2 -= 0x20;
        if (c1=='\0')
            return ((c2=='\0') ? 0 : -1);
        if (c2=='\0')
            return 1;
        if (c1<c2)
            return -1;
        if (c1>c2)
            return 1;
    }
}


#ifdef  CASESENSITIVITYDEFAULT_NO
#define CASESENSITIVITYDEFAULTVALUE 2
#else
#define CASESENSITIVITYDEFAULTVALUE 1
#endif

#ifndef STRCMPCASENOSENTIVEFUNCTION
#define STRCMPCASENOSENTIVEFUNCTION strcmpcasenosensitive_internal
#endif

/*
   Compare two filename (fileName1,fileName2).
   If iCaseSenisivity = 1, comparision is case sensitivity (like strcmp)
   If iCaseSenisivity = 2, comparision is not case sensitivity (like strcmpi
                                                                or strcasecmp)
   If iCaseSenisivity = 0, case sensitivity is defaut of your operating system
        (like 1 on Unix, 2 on Windows)

*/
extern int ZEXPORT unzStringFileNameCompare (fileName1,fileName2,iCaseSensitivity)
    const char* fileName1;
    const char* fileName2;
    int iCaseSensitivity;
{
    if (iCaseSensitivity==0)
        iCaseSensitivity=CASESENSITIVITYDEFAULTVALUE;

    if (iCaseSensitivity==1)
        return strcmp(fileName1,fileName2);

    return STRCMPCASENOSENTIVEFUNCTION(fileName1,fileName2);
}

#ifndef BUFREADCOMMENT
#define BUFREADCOMMENT (0x400)
#endif

/*
  Locate the Central directory of a zipfile (at the end, just before
    the global comment)
*/
local uLong unzlocal_SearchCentralDir OF((
    const zlib_filefunc_def* pzlib_filefunc_def,
    voidpf filestream));

local uLong unzlocal_SearchCentralDir(pzlib_filefunc_def,filestream)
    const zlib_filefunc_def* pzlib_filefunc_def;
    voidpf filestream;
{
    unsigned char* buf;
    uLong uSizeFile;
    uLong uBackRead;
    uLong uMaxBack=0xffff; /* maximum size of global comment */
    uLong uPosFound=0;

    if (ZSEEK(*pzlib_filefunc_def,filestream,0,ZLIB_FILEFUNC_SEEK_END) != 0)
        return 0;


    uSizeFile = ZTELL(*pzlib_filefunc_def,filestream);

    if (uMaxBack>uSizeFile)
        uMaxBack = uSizeFile;

    buf = (unsigned char*)ALLOC(BUFREADCOMMENT+4);
    if (buf==NULL)
        return 0;

    uBackRead = 4;
    while (uBackRead<uMaxBack)
    {
        uLong uReadSize,uReadPos ;
        int i;
        if (uBackRead+BUFREADCOMMENT>uMaxBack)
            uBackRead = uMaxBack;
        else
            uBackRead+=BUFREADCOMMENT;
        uReadPos = uSizeFile-uBackRead ;

        uReadSize = ((BUFREADCOMMENT+4) < (uSizeFile-uReadPos)) ?
                     (BUFREADCOMMENT+4) : (uSizeFile-uReadPos);
        if (ZSEEK(*pzlib_filefunc_def,filestream,uReadPos,ZLIB_FILEFUNC_SEEK_SET)!=0)
            break;

        if (ZREAD(*pzlib_filefunc_def,filestream,buf,uReadSize)!=uReadSize)
            break;

        for (i=(int)uReadSize-3; (i--)>0;)
            if (((*(buf+i))==0x50) && ((*(buf+i+1))==0x4b) &&
                ((*(buf+i+2))==0x05) && ((*(buf+i+3))==0x06))
            {
                uPosFound = uReadPos+i;
                break;
            }

        if (uPosFound!=0)
            break;
    }
    TRYFREE(buf);
    return uPosFound;
}

/*
  Open a Zip file. path contain the full pathname (by example,
     on a Windows NT computer "c:\\test\\zlib114.zip" or on an Unix computer
     "zlib/zlib114.zip".
     If the zipfile cannot be opened (file doesn't exist or in not valid), the
       return value is NULL.
     Else, the return value is a unzFile Handle, usable with other function
       of this unzip package.
*/
extern unzFile ZEXPORT unzOpen2 (path, pzlib_filefunc_def)
    const char *path;
    zlib_filefunc_def* pzlib_filefunc_def;
{