/* zip.c -- IO on .zip files using zlib 
   Version 0.15 beta, Mar 19th, 1998,

   Read zip.h for more info
*/


#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "zlib.h"
#include "zip.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 VERSIONMADEBY
# define VERSIONMADEBY   (0x0) /* platform depedent */
#endif

#ifndef Z_BUFSIZE
#define Z_BUFSIZE (16384)
#endif

#ifndef Z_MAXFILENAMEINZIP
#define Z_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)
*/

/* I've found an old Unix (a SunOS 4.1.3_U1) without all SEEK_* defined.... */

#ifndef SEEK_CUR
#define SEEK_CUR    1
#endif

#ifndef SEEK_END
#define SEEK_END    2
#endif

#ifndef SEEK_SET
#define SEEK_SET    0
#endif

const char zip_copyright[] =
   " zip 0.15 Copyright 1998 Gilles Vollant ";


#define SIZEDATA_INDATABLOCK (4096-(4*4))

#define LOCALHEADERMAGIC    (0x04034b50)
#define CENTRALHEADERMAGIC  (0x02014b50)
#define ENDHEADERMAGIC      (0x06054b50)

#define FLAG_LOCALHEADER_OFFSET (0x06)
#define CRC_LOCALHEADER_OFFSET  (0x0e)

#define SIZECENTRALHEADER (0x2e) /* 46 */

typedef struct linkedlist_datablock_internal_s
{
  struct linkedlist_datablock_internal_s* next_datablock;
  uLong  avail_in_this_block;
  uLong  filled_in_this_block;
  uLong  unused; /* for future use and alignement */
  unsigned char data[SIZEDATA_INDATABLOCK];
} linkedlist_datablock_internal;

typedef struct linkedlist_data_s
{
    linkedlist_datablock_internal* first_block;
    linkedlist_datablock_internal* last_block;
} linkedlist_data;


typedef struct
{
	z_stream stream;            /* zLib stream structure for inflate */
    int  stream_initialised;    /* 1 is stream is initialised */
    uInt pos_in_buffered_data;  /* last written byte in buffered_data */

    uLong pos_local_header;     /* offset of the local header of the file 
                                     currenty writing */
    char* central_header;       /* central header data for the current file */
    uLong size_centralheader;   /* size of the central header for cur file */
    uLong flag;                 /* flag of the file currently writing */

    int  method;                /* compression method of file currenty wr.*/
    Byte buffered_data[Z_BUFSIZE];/* buffer contain compressed data to be writ*/
    uLong dosDate;
    uLong crc32;
} curfile_info;

typedef struct
{
    FILE * filezip;
    linkedlist_data central_dir;/* datablock with central dir in construction*/
    int  in_opened_file_inzip;  /* 1 if a file in the zip is currently writ.*/
    curfile_info ci;            /* info on the file curretly writing */

    uLong begin_pos;            /* position of the beginning of the zipfile */
    uLong number_entry;
} zip_internal;

local linkedlist_datablock_internal* allocate_new_datablock()
{
    linkedlist_datablock_internal* ldi;
    ldi = (linkedlist_datablock_internal*)
                 ALLOC(sizeof(linkedlist_datablock_internal));
    if (ldi!=NULL)
    {
        ldi->next_datablock = NULL ;
        ldi->filled_in_this_block = 0 ;
        ldi->avail_in_this_block = SIZEDATA_INDATABLOCK ;
    }
    return ldi;
}

local void free_datablock(ldi)
    linkedlist_datablock_internal* ldi;
{
    while (ldi!=NULL)
    {
        linkedlist_datablock_internal* ldinext = ldi->next_datablock;
        TRYFREE(ldi);
        ldi = ldinext;
    }
}

local void init_linkedlist(ll)
    linkedlist_data* ll;
{
    ll->first_block = ll->last_block = NULL;
}

local void free_linkedlist(ll)
    linkedlist_data* ll;
{
    free_datablock(ll->first_block);
    ll->first_block = ll->last_block = NULL;
}


local int add_data_in_datablock(ll,buf,len)
    linkedlist_data* ll;    
    const void* buf;
    uLong len;
{
    linkedlist_datablock_internal* ldi;
    const unsigned char* from_copy;

    if (ll==NULL)
        return ZIP_INTERNALERROR;

    if (ll->last_block == NULL)
    {
        ll->first_block = ll->last_block = allocate_new_datablock();
        if (ll->first_block == NULL)
            return ZIP_INTERNALERROR;
    }

    ldi = ll->last_block;
    from_copy = (unsigned char*)buf;

    while (len>0)
    {
        uInt copy_this;
        uInt i;
        unsigned char* to_copy;

        if (ldi->avail_in_this_block==0)
        {
            ldi->next_datablock = allocate_new_datablock();
            if (ldi->next_datablock == NULL)
                return ZIP_INTERNALERROR;
            ldi = ldi->next_datablock ;
            ll->last_block = ldi;
        }

        if (ldi->avail_in_this_block < len)
            copy_this = (uInt)ldi->avail_in_this_block;
        else
            copy_this = (uInt)len;

        to_copy = &(ldi->data[ldi->filled_in_this_block]);

        for (i=0;i<copy_this;i++)
            *(to_copy+i)=*(from_copy+i);

        ldi->filled_in_this_block += copy_this;
        ldi->avail_in_this_block -= copy_this;
        from_copy += copy_this ;
        len -= copy_this;
    }
    return ZIP_OK;
}


local int write_datablock(fout,ll)
    FILE * fout;
    linkedlist_data* ll;    
{
    linkedlist_datablock_internal* ldi;
    ldi = ll->first_block;
    while (ldi!=NULL)
    {
        if (ldi->filled_in_this_block > 0)
            if (fwrite(ldi->data,(uInt)ldi->filled_in_this_block,1,fout)!=1)
                return ZIP_ERRNO;
        ldi = ldi->next_datablock;
    }
    return ZIP_OK;
}

/****************************************************************************/

/* ===========================================================================
   Outputs a long in LSB order to the given file
   nbByte == 1, 2 or 4 (byte, short or long)
*/

local int ziplocal_putValue OF((FILE *file, uLong x, int nbByte));
local int ziplocal_putValue (file, x, nbByte)
    FILE *file;
    uLong x;
    int nbByte;
{
    unsigned char buf[4];
    int n;
    for (n = 0; n < nbByte; n++) {
        buf[n] = (unsigned char)(x & 0xff);
        x >>= 8;
    }
    if (fwrite(buf,nbByte,1,file)!=1)
        return ZIP_ERRNO;
    else
        return ZIP_OK;
}

local void ziplocal_putValue_inmemory OF((void* dest, uLong x, int nbByte));
local void ziplocal_putValue_inmemory (dest, x, nbByte)
    void* dest;
    uLong x;
    int nbByte;
{
    unsigned char* buf=(unsigned char*)dest;
    int n;
    for (n = 0; n < nbByte; n++) {
        buf[n] = (unsigned char)(x & 0xff);
        x >>= 8;
    }
}
/****************************************************************************/


local uLong ziplocal_TmzDateToDosDate(ptm,dosDate)
    tm_zip* ptm;
    uLong dosDate;
{
    uLong year = (uLong)ptm->tm_year;
    if (year>1980)
        year-=1980;
    else if (year>80)
        year-=80;
    return
      (uLong) (((ptm->tm_mday) + (32 * (ptm->tm_mon+1)) + (512 * year)) << 16) |
        ((ptm->tm_sec/2) + (32* ptm->tm_min) + (2048 * (uLong)ptm->tm_hour));
}


/****************************************************************************/

extern zipFile ZEXPORT zipOpen (pathname, append)
    const char *pathname;
    int append;
{
    zip_internal ziinit;
    zip_internal* zi;

    ziinit.filezip = fopen(pathname,(append == 0) ? "wb" : "ab");
    if (ziinit.filezip == NULL)
        return NULL;
    ziinit.begin_pos = ftell(ziinit.filezip);
    ziinit.in_opened_file_inzip = 0;
    ziinit.ci.stream_initialised = 0;
    ziinit.number_entry = 0;
    init_linkedlist(&(ziinit.central_dir));


    zi = (zip_internal*)ALLOC(sizeof(zip_internal));
    if (zi==NULL)
    {
        fclose(ziinit.filezip);
        return NULL;
    }

    *zi = ziinit;
    return (zipFile)zi;
}

extern int ZEXPORT zipOpenNewFileInZip (file, filename, zipfi, 
                                        extrafield_local, size_extrafield_local,
                                        extrafield_global, size_extrafield_global,
                                        comment, method, level)
    zipFile file;
    const char* filename;
    const zip_fileinfo* zipfi;
    const void* extrafield_local;
    uInt size_extrafield_local;
    const void* extrafield_global;
    uInt size_extrafield_global;
    const char* comment;
    int method;
    int level;
{
    zip_internal* zi;
    uInt size_filename;
    uInt size_comment;
    uInt i;
    int err = ZIP_OK;

    if (file == NULL)
        return ZIP_PARAMERROR;
    if ((method!=0) && (method!=Z_DEFLATED))
        return ZIP_PARAMERROR;

    zi = (zip_internal*)file;

    if (zi->in_opened_file_inzip == 1)
    {
        err = zipCloseFileInZip (file);
        if (err != ZIP_OK)
            return err;
    }