user32/tests: Fix a couple of dimension checks on W2k3 and Vista.

[wine/multimedia.git] / dlls / storage.dll16 / storage.c

/* Compound Storage
 *
 * Implemented using the documentation of the LAOLA project at
 * <URL:http://wwwwbs.cs.tu-berlin.de/~schwartz/pmh/index.html>
 * (Thanks to Martin Schwartz <schwartz@cs.tu-berlin.de>)
 *
 * Copyright 1998 Marcus Meissner
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */

#include "config.h"

#include <assert.h>
#include <time.h>
#include <stdarg.h>
#include <string.h>
#include <sys/types.h>
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif

#define NONAMELESSUNION
#define NONAMELESSSTRUCT
#include "windef.h"
#include "winbase.h"
#include "winternl.h"
#include "winerror.h"
#include "wine/winbase16.h"
#include "wownt32.h"
#include "wine/unicode.h"
#include "objbase.h"
#include "wine/debug.h"

#include "ifs.h"

WINE_DEFAULT_DEBUG_CHANNEL(ole);
WINE_DECLARE_DEBUG_CHANNEL(relay);

struct storage_header {
        BYTE    magic[8];       /* 00: magic */
        BYTE    unknown1[36];   /* 08: unknown */
        DWORD   num_of_bbd_blocks;/* 2C: length of big datablocks */
        DWORD   root_startblock;/* 30: root storage first big block */
        DWORD   unknown2[2];    /* 34: unknown */
        DWORD   sbd_startblock; /* 3C: small block depot first big block */
        DWORD   unknown3[3];    /* 40: unknown */
        DWORD   bbd_list[109];  /* 4C: big data block list (up to end of sector)*/
};
struct storage_pps_entry {
        WCHAR   pps_rawname[32];/* 00: \0 terminated widechar name */
        WORD    pps_sizeofname; /* 40: namelength in bytes */
        BYTE    pps_type;       /* 42: flags, 1 storage/dir, 2 stream, 5 root */
        BYTE    pps_unknown0;   /* 43: unknown */
        DWORD   pps_prev;       /* 44: previous pps */
        DWORD   pps_next;       /* 48: next pps */
        DWORD   pps_dir;        /* 4C: directory pps */
        GUID    pps_guid;       /* 50: class ID */
        DWORD   pps_unknown1;   /* 60: unknown */
        FILETIME pps_ft1;       /* 64: filetime1 */
        FILETIME pps_ft2;       /* 70: filetime2 */
        DWORD   pps_sb;         /* 74: data startblock */
        DWORD   pps_size;       /* 78: datalength. (<0x1000)?small:big blocks*/
        DWORD   pps_unknown2;   /* 7C: unknown */
};

#define STORAGE_CHAINENTRY_FAT          0xfffffffd
#define STORAGE_CHAINENTRY_ENDOFCHAIN   0xfffffffe
#define STORAGE_CHAINENTRY_FREE         0xffffffff


static const BYTE STORAGE_magic[8]   ={0xd0,0xcf,0x11,0xe0,0xa1,0xb1,0x1a,0xe1};

#define BIGSIZE         512
#define SMALLSIZE               64

#define SMALLBLOCKS_PER_BIGBLOCK        (BIGSIZE/SMALLSIZE)

#define READ_HEADER(str)        STORAGE_get_big_block(str,-1,(LPBYTE)&sth);assert(!memcmp(STORAGE_magic,sth.magic,sizeof(STORAGE_magic)));
static IStorage16Vtbl stvt16;
static const IStorage16Vtbl *segstvt16 = NULL;
static IStream16Vtbl strvt16;
static const IStream16Vtbl *segstrvt16 = NULL;

/*ULONG WINAPI IStorage16_AddRef(LPSTORAGE16 this);*/
static void _create_istorage16(LPSTORAGE16 *stg);
static void _create_istream16(LPSTREAM16 *str);

#define IMPLEMENTED 1

/* The following is taken from the CorVu implementation of docfiles, and
 * documents things about the file format that are not implemented here, and
 * not documented by the LAOLA project. The CorVu implementation was posted
 * to wine-devel in February 2004, and released under the LGPL at the same
 * time. Because that implementation is in C++, it's not directly usable in
 * Wine, but does have documentation value.
 *
 *
 * #define DF_EXT_VTOC          -4
 * #define DF_VTOC_VTOC         -3
 * #define DF_VTOC_EOF          -2
 * #define DF_VTOC_FREE         -1
 * #define DF_NAMELEN   0x20    // Maximum entry name length - 31 characters plus
 *                              // a NUL terminator
 *
 * #define DF_FT_STORAGE        1
 * #define DF_FT_STREAM         2
 * #define DF_FT_LOCKBYTES      3       // Not used -- How the bloody hell did I manage
 * #define DF_FT_PROPERTY       4       // Not Used -- to figure these two out?
 * #define DF_FT_ROOT           5
 *
 * #define DF_BLOCK_SIZE        0x200
 * #define DF_VTOC_SIZE         0x80
 * #define DF_DE_PER_BLOCK      4
 * #define DF_STREAM_BLOCK_SIZE 0x40
 *
 * A DocFile is divided into blocks of 512 bytes.
 * The first block contains the header.
 *
 * The file header contains The first 109 entries in the VTOC of VTOCs.
 *
 * Each block pointed to by a VTOC of VTOCs contains a VTOC, which
 * includes block chains - just like FAT. This is a somewhat poor
 * design for the following reasons:
 *
 *      1. FAT was a poor file system design to begin with, and
 *         has long been known to be horrendously inefficient
 *         for day to day operations.
 *
 *      2. The problem is compounded here, since the file
 *         level streams are generally *not* read sequentially.
 *         This means that a significant percentage of reads
 *         require seeking from the start of the chain.
 *
 * Data chains also contain an internal VTOC. The block size for
 * the standard VTOC is 512. The block size for the internal VTOC
 * is 64.
 *
 * Now, the 109 blocks in the VTOC of VTOCs allows for files of
 * up to around 7MB. So what do you think happens if that's
 * exceeded? Well, there's an entry in the header block which
 * points to the first block used as additional storage for
 * the VTOC of VTOCs.
 *
 * Now we can get up to around 15MB. Now, guess how the file
 * format adds in another block to the VTOC of VTOCs. Come on,
 * it's no big surprise. That's right - the last entry in each
 * block extending the VTOC of VTOCs is, you guessed it, the
 * block number of the next block containing an extension to
 * the VTOC of VTOCs. The VTOC of VTOCs is chained!!!!
 *
 * So, to review:
 *
 * 1. If you are using a FAT file system, the location of
 *    your file's blocks is stored in chains.
 *
 * 2. At the abstract level, the file contains a VTOC of VTOCs,
 *    which is stored in the most inefficient possible format for
 *    random access - a chain (AKA list).
 *
 * 3. The VTOC of VTOCs contains descriptions of three file level
 *    streams:
 *
 *    a. The Directory stream
 *    b. The Data stream
 *    c. The Data VTOC stream
 *
 *    These are, of course, represented as chains.
 *
 * 4. The Data VTOC contains data describing the chains of blocks
 *    within the Data stream.
 *
 * That's right - we have a total of four levels of block chains!
 *
 * Now, is that complicated enough for you? No? OK, there's another
 * complication. If an individual stream (ie. an IStream) reaches
 * 4096 bytes in size, it gets moved from the Data Stream to
 * a new file level stream. Now, if the stream then gets truncated
 * back to less than 4096 bytes, it returns to the data stream.
 *
 * The effect of using this format can be seen very easily. Pick
 * an arbitrary application with a grid data representation that
 * can export to both Lotus 123 and Excel 5 or higher. Export
 * a large file to Lotus 123 and time it. Export the same thing
 * to Excel 5 and time that. The difference is the inefficiency
 * of the Microsoft DocFile format.
 *
 *
 * #define TOTAL_SIMPLE_VTOCS   109
 *
 * struct       DocFile_Header
 * {
 *      df_byte iMagic1;        // 0xd0
 *      df_byte iMagic2;        // 0xcf
 *      df_byte iMagic3;        // 0x11
 *      df_byte iMagic4;        // 0xe0 - Spells D0CF11E0, or DocFile
 *      df_byte iMagic5;        // 161  (igi upside down)
 *      df_byte iMagic6;        // 177  (lli upside down - see below
 *      df_byte iMagic7;        // 26 (gz upside down)
 *      df_byte iMagic8;        // 225 (szz upside down) - see below
 *      df_int4 aiUnknown1[4];
 *      df_int4 iVersion;       // DocFile Version - 0x03003E
 *      df_int4 aiUnknown2[4];
 *      df_int4 nVTOCs;         // Number of VTOCs
 *      df_int4 iFirstDirBlock; // First Directory Block
 *      df_int4 aiUnknown3[2];
 *      df_int4 iFirstDataVTOC; // First data VTOC block
 *      df_int4 iHasData;       // 1 if there is data in the file - yes, this is important
 *      df_int4 iExtendedVTOC;  // Extended VTOC location
 *      df_int4 iExtendedVTOCSize; // Size of extended VTOC (+1?)
 *      df_int4 aiVTOCofVTOCs[TOTAL_SIMPLE_VTOCS];
 * };
 *
 * struct       DocFile_VTOC
 * {
 *      df_int4 aiBlocks[DF_VTOC_SIZE];
 * };
 *
 *
 * The meaning of the magic numbers
 *
 * 0xd0cf11e0 is DocFile with a zero on the end (sort of)
 *
 * If you key 177161 into a calculator, then turn the calculator
 * upside down, you get igilli, which may be a reference to
 * somebody's name, or to the Hebrew word for "angel".
 *
 * If you key 26225 into a calculator, then turn it upside down, you
 * get szzgz. Microsoft has a tradition of creating nonsense words
 * using the letters s, g, z and y. We think szzgz may be one of the
 * Microsoft placeholder variables, along the lines of foo, bar and baz.
 * Alternatively, it could be 22526, which would be gzszz.
 *
 *
 * struct       DocFile_DirEnt
 * {
 *      df_char achEntryName[DF_NAMELEN];       // Entry Name
 *      df_int2 iNameLen;                       // Name length in bytes, including NUL terminator
 *      df_byte iFileType;                      // Entry type
 *      df_byte iColour;                        // 1 = Black, 0 = Red
 *      df_int4 iLeftSibling;                   // Next Left Sibling Entry - See below
 *      df_int4 iRightSibling;                  // Next Right Sibling Entry
 *      df_int4 iFirstChild;                    // First Child Entry
 *      df_byte achClassID[16];                 // Class ID
 *      df_int4 iStateBits;                     // [GS]etStateBits value
 *      df_int4 iCreatedLow;                    // Low DWORD of creation time
 *      df_int4 iCreatedHigh;                   // High DWORD of creation time
 *      df_int4 iModifiedLow;                   // Low DWORD of modification time
 *      df_int4 iModifiedHigh;                  // High DWORD of modification time
 *      df_int4 iVTOCPosition;                  // VTOC Position
 *      df_int4 iFileSize;                      // Size of the stream
 *      df_int4 iZero;                          // We think this is part of the 64 bit stream size - must be 0
 * };
 *
 * Siblings
 * ========
 *
 * Siblings are stored in an obscure but incredibly elegant
 * data structure called a red-black tree. This is generally
 * defined as a 2-3-4 tree stored in a binary tree.
 *
 * A red-black tree can always be balanced very easily. The rules
 * for a red-black tree are as follows:
 *
 *      1. The root node is always black.
 *      2. The parent of a red node is always black.
 *
 * There is a Java demo of red-black trees at:
 *
 *      http://langevin.usc.edu/BST/RedBlackTree-Example.html
 *
 * This demo is an excellent tool for learning how red-black
 * trees work, without having to go through the process of
 * learning how they were derived.
 *
 * Within the tree, elements are ordered by the length of the
 * name and within that, ASCII order by name. This causes the
 * apparently bizarre reordering you see when you use dfview.
 *
 * This is a somewhat bizarre choice. It suggests that the
 * designer of the DocFile format was trying to optimise
 * searching through the directory entries. However searching
 * through directory entries is a relatively rare operation.
 * Reading and seeking within a stream are much more common
 * operations, especially within the file level streams, yet
 * these use the horrendously inefficient FAT chains.
 *
 * This suggests that the designer was probably somebody
 * fresh out of university, who had some basic knowledge of
 * basic data structures, but little knowledge of anything
 * more practical. It is bizarre to attempt to optimise
 * directory searches while not using a more efficient file
 * block locating system than FAT (seedling/sapling/tree
 * would result in a massive improvement - in fact we have
 * an alternative to docfiles that we use internally that
 * uses seedling/sapling/tree and *is* far more efficient).
 *
 * It is worth noting that the MS implementation of red-black
 * trees is incorrect (I can tell you're surprised) and
 * actually causes more operations to occur than are really
 * needed. Fortunately the fact that our implementation is
 * correct will not cause any problems - the MS implementation
 * still appears to cause the tree to satisfy the rules, albeit
 * a sequence of the same insertions in the different
 * implementations may result in a different, and possibly
 * deeper (but never shallower) tree.
 */

typedef struct {
        HANDLE          hf;
        SEGPTR          lockbytes;
} stream_access16;
/* --- IStorage16 implementation struct */

typedef struct
{
        /* IUnknown fields */
        const IStorage16Vtbl           *lpVtbl;
        LONG                            ref;
        /* IStorage16 fields */
        SEGPTR                          thisptr; /* pointer to this struct as segmented */
        struct storage_pps_entry        stde;
        int                             ppsent;
        stream_access16                 str;
} IStorage16Impl;


/******************************************************************************
 *              STORAGE_get_big_block   [Internal]
 *
 * Reading OLE compound storage
 */
static BOOL
STORAGE_get_big_block(stream_access16 *str,int n,BYTE *block)
{
    DWORD result;

    assert(n>=-1);
    if (str->hf) {
        if ((SetFilePointer( str->hf, (n+1)*BIGSIZE, NULL,
                             SEEK_SET ) == INVALID_SET_FILE_POINTER) && GetLastError())
        {
            WARN("(%p,%d,%p), seek failed (%d)\n",str->hf, n, block, GetLastError());
            return FALSE;
        }
        if (!ReadFile( str->hf, block, BIGSIZE, &result, NULL ) || result != BIGSIZE)
        {
            WARN("(hf=%p, block size %d): read didn't read (%d)\n",str->hf,n,GetLastError());
            return FALSE;
        }
    } else {
        DWORD args[6];
        HRESULT hres;
        HANDLE16 hsig;

        args[0] = (DWORD)str->lockbytes;        /* iface */
        args[1] = (n+1)*BIGSIZE;
        args[2] = 0;    /* ULARGE_INTEGER offset */
        args[3] = WOWGlobalAllocLock16( 0, BIGSIZE, &hsig ); /* sig */
        args[4] = BIGSIZE;
        args[5] = 0;

        if (!WOWCallback16Ex(
            (DWORD)((const ILockBytes16Vtbl*)MapSL(
                        (SEGPTR)((LPLOCKBYTES16)MapSL(str->lockbytes))->lpVtbl)
            )->ReadAt,
            WCB16_PASCAL,
            6*sizeof(DWORD),
            (LPVOID)args,
            (LPDWORD)&hres
        )) {
            ERR("CallTo16 ILockBytes16::ReadAt() failed, hres %x\n",hres);
            return FALSE;
        }
        memcpy(block, MapSL(args[3]), BIGSIZE);
        WOWGlobalUnlockFree16(args[3]);
    }
    return TRUE;
}

static BOOL
_ilockbytes16_writeat(SEGPTR lockbytes, DWORD offset, DWORD length, void *buffer) {
    DWORD args[6];
    HRESULT hres;

    args[0] = (DWORD)lockbytes; /* iface */
    args[1] = offset;
    args[2] = 0;        /* ULARGE_INTEGER offset */
    args[3] = (DWORD)MapLS( buffer );
    args[4] = length;
    args[5] = 0;

    /* THIS_ ULARGE_INTEGER ulOffset, const void *pv, ULONG cb, ULONG *pcbWritten); */

    if (!WOWCallback16Ex(
        (DWORD)((const ILockBytes16Vtbl*)MapSL(
                    (SEGPTR)((LPLOCKBYTES16)MapSL(lockbytes))->lpVtbl)
        )->WriteAt,
        WCB16_PASCAL,
        6*sizeof(DWORD),
        (LPVOID)args,
        (LPDWORD)&hres
    )) {
        ERR("CallTo16 ILockBytes16::WriteAt() failed, hres %x\n",hres);
        return FALSE;
    }
    UnMapLS(args[3]);
    return TRUE;
}

/******************************************************************************
 * STORAGE_put_big_block [INTERNAL]
 */
static BOOL
STORAGE_put_big_block(stream_access16 *str,int n,BYTE *block)
{
    DWORD result;

    assert(n>=-1);
    if (str->hf) {
        if ((SetFilePointer( str->hf, (n+1)*BIGSIZE, NULL,
                             SEEK_SET ) == INVALID_SET_FILE_POINTER) && GetLastError())
        {
            WARN("seek failed (%d)\n",GetLastError());
            return FALSE;
        }
        if (!WriteFile( str->hf, block, BIGSIZE, &result, NULL ) || result != BIGSIZE)
        {
            WARN(" write failed (%d)\n",GetLastError());
            return FALSE;
        }
        return TRUE;
    } else {
        _ilockbytes16_writeat(str->lockbytes, (n+1)*BIGSIZE, BIGSIZE, block);
        return TRUE;
    }
}

/******************************************************************************
 * STORAGE_get_next_big_blocknr [INTERNAL]
 */
static int
STORAGE_get_next_big_blocknr(stream_access16 *str,int blocknr) {
        INT     bbs[BIGSIZE/sizeof(INT)];
        struct  storage_header  sth;

        READ_HEADER(str);

        assert(blocknr>>7<sth.num_of_bbd_blocks);
        if (sth.bbd_list[blocknr>>7]==0xffffffff)
                return -5;
        if (!STORAGE_get_big_block(str,sth.bbd_list[blocknr>>7],(LPBYTE)bbs))
                return -5;
        assert(bbs[blocknr&0x7f]!=STORAGE_CHAINENTRY_FREE);
        return bbs[blocknr&0x7f];
}

/******************************************************************************
 * STORAGE_get_nth_next_big_blocknr [INTERNAL]
 */
static int
STORAGE_get_nth_next_big_blocknr(stream_access16 *str,int blocknr,int nr) {
        INT     bbs[BIGSIZE/sizeof(INT)];
        int     lastblock = -1;
        struct storage_header sth;

        TRACE("(blocknr=%d, nr=%d)\n", blocknr, nr);
        READ_HEADER(str);

        assert(blocknr>=0);
        while (nr--) {
                assert((blocknr>>7)<sth.num_of_bbd_blocks);
                assert(sth.bbd_list[blocknr>>7]!=0xffffffff);

                /* simple caching... */
                if (lastblock!=sth.bbd_list[blocknr>>7]) {
                        BOOL ret = STORAGE_get_big_block(str,sth.bbd_list[blocknr>>7],(LPBYTE)bbs);
                        assert(ret);
                        lastblock = sth.bbd_list[blocknr>>7];
                }
                blocknr = bbs[blocknr&0x7f];
        }
        return blocknr;
}

/******************************************************************************
 *              STORAGE_get_root_pps_entry      [Internal]
 */
static BOOL
STORAGE_get_root_pps_entry(stream_access16* str,struct storage_pps_entry *pstde) {
        int     blocknr,i;
        BYTE    block[BIGSIZE];
        struct storage_pps_entry        *stde=(struct storage_pps_entry*)block;
        struct storage_header sth;

        READ_HEADER(str);
        blocknr = sth.root_startblock;
        TRACE("startblock is %d\n", blocknr);
        while (blocknr>=0) {
                BOOL ret = STORAGE_get_big_block(str,blocknr,block);
                assert(ret);
                for (i=0;i<4;i++) {
                        if (!stde[i].pps_sizeofname)
                                continue;
                        if (stde[i].pps_type==5) {
                                *pstde=stde[i];
                                return TRUE;
                        }
                }
                blocknr=STORAGE_get_next_big_blocknr(str,blocknr);
                TRACE("next block is %d\n", blocknr);
        }
        return FALSE;
}

/******************************************************************************
 * STORAGE_get_small_block [INTERNAL]
 */
static BOOL
STORAGE_get_small_block(stream_access16 *str,int blocknr,BYTE *sblock) {
        BYTE                            block[BIGSIZE];
        int                             bigblocknr;
        struct storage_pps_entry        root;
        BOOL ret;

        TRACE("(blocknr=%d)\n", blocknr);
        assert(blocknr>=0);
        ret = STORAGE_get_root_pps_entry(str,&root);
        assert(ret);
        bigblocknr = STORAGE_get_nth_next_big_blocknr(str,root.pps_sb,blocknr/SMALLBLOCKS_PER_BIGBLOCK);
        assert(bigblocknr>=0);
        ret = STORAGE_get_big_block(str,bigblocknr,block);
        assert(ret);

        memcpy(sblock,((LPBYTE)block)+SMALLSIZE*(blocknr&(SMALLBLOCKS_PER_BIGBLOCK-1)),SMALLSIZE);
        return TRUE;
}

/******************************************************************************
 * STORAGE_put_small_block [INTERNAL]
 */
static BOOL
STORAGE_put_small_block(stream_access16 *str,int blocknr,const BYTE *sblock) {
        BYTE                            block[BIGSIZE];
        int                             bigblocknr;
        struct storage_pps_entry        root;
        BOOL ret;

        assert(blocknr>=0);
        TRACE("(blocknr=%d)\n", blocknr);

        ret = STORAGE_get_root_pps_entry(str,&root);
        assert(ret);
        bigblocknr = STORAGE_get_nth_next_big_blocknr(str,root.pps_sb,blocknr/SMALLBLOCKS_PER_BIGBLOCK);
        assert(bigblocknr>=0);
        ret = STORAGE_get_big_block(str,bigblocknr,block);
        assert(ret);

        memcpy(((LPBYTE)block)+SMALLSIZE*(blocknr&(SMALLBLOCKS_PER_BIGBLOCK-1)),sblock,SMALLSIZE);
        ret = STORAGE_put_big_block(str,bigblocknr,block);
        assert(ret);
        return TRUE;
}

/******************************************************************************
 * STORAGE_get_next_small_blocknr [INTERNAL]
 */
static int
STORAGE_get_next_small_blocknr(stream_access16 *str,int blocknr) {
        BYTE                            block[BIGSIZE];
        LPINT                           sbd = (LPINT)block;
        int                             bigblocknr;
        struct storage_header           sth;
        BOOL ret;

        TRACE("(blocknr=%d)\n", blocknr);
        READ_HEADER(str);
        assert(blocknr>=0);
        bigblocknr = STORAGE_get_nth_next_big_blocknr(str,sth.sbd_startblock,blocknr/128);
        assert(bigblocknr>=0);
        ret = STORAGE_get_big_block(str,bigblocknr,block);
        assert(ret);
        assert(sbd[blocknr & 127]!=STORAGE_CHAINENTRY_FREE);
        return sbd[blocknr & (128-1)];
}

/******************************************************************************
 * STORAGE_get_nth_next_small_blocknr [INTERNAL]
 */
static int
STORAGE_get_nth_next_small_blocknr(stream_access16*str,int blocknr,int nr) {
        int     lastblocknr=-1;
        BYTE    block[BIGSIZE];
        LPINT   sbd = (LPINT)block;
        struct storage_header sth;
        BOOL ret;

        TRACE("(blocknr=%d, nr=%d)\n", blocknr, nr);
        READ_HEADER(str);
        assert(blocknr>=0);
        while ((nr--) && (blocknr>=0)) {
                if (lastblocknr/128!=blocknr/128) {
                        int     bigblocknr;
                        bigblocknr = STORAGE_get_nth_next_big_blocknr(str,sth.sbd_startblock,blocknr/128);
                        assert(bigblocknr>=0);
                        ret = STORAGE_get_big_block(str,bigblocknr,block);
                        assert(ret);
                        lastblocknr = blocknr;
                }
                assert(lastblocknr>=0);
                lastblocknr=blocknr;
                blocknr=sbd[blocknr & (128-1)];
                assert(blocknr!=STORAGE_CHAINENTRY_FREE);
        }
        return blocknr;
}

/******************************************************************************
 * STORAGE_get_pps_entry [INTERNAL]
 */
static int
STORAGE_get_pps_entry(stream_access16*str,int n,struct storage_pps_entry *pstde) {
        int     blocknr;
        BYTE    block[BIGSIZE];
        struct storage_pps_entry *stde = (struct storage_pps_entry*)(((LPBYTE)block)+128*(n&3));
        struct storage_header sth;
        BOOL ret;

        TRACE("(n=%d)\n", n);
        READ_HEADER(str);
        /* we have 4 pps entries per big block */
        blocknr = STORAGE_get_nth_next_big_blocknr(str,sth.root_startblock,n/4);
        assert(blocknr>=0);
        ret = STORAGE_get_big_block(str,blocknr,block);
        assert(ret);

        *pstde=*stde;
        return 1;
}

/******************************************************************************
 *              STORAGE_put_pps_entry   [Internal]
 */
static int
STORAGE_put_pps_entry(stream_access16*str,int n,const struct storage_pps_entry *pstde) {
        int     blocknr;
        BYTE    block[BIGSIZE];
        struct storage_pps_entry *stde = (struct storage_pps_entry*)(((LPBYTE)block)+128*(n&3));
        struct storage_header sth;
        BOOL ret;

        TRACE("(n=%d)\n", n);
        READ_HEADER(str);
        /* we have 4 pps entries per big block */
        blocknr = STORAGE_get_nth_next_big_blocknr(str,sth.root_startblock,n/4);
        assert(blocknr>=0);
        ret = STORAGE_get_big_block(str,blocknr,block);
        assert(ret);
        *stde=*pstde;
        ret = STORAGE_put_big_block(str,blocknr,block);
        assert(ret);
        return 1;
}

/******************************************************************************
 *              STORAGE_look_for_named_pps      [Internal]
 */
static int
STORAGE_look_for_named_pps(stream_access16*str,int n,LPOLESTR name) {
        struct storage_pps_entry        stde;
        int                             ret;

        TRACE("(n=%d,name=%s)\n", n, debugstr_w(name));
        if (n==-1)
                return -1;
        if (1!=STORAGE_get_pps_entry(str,n,&stde))
                return -1;

        if (!lstrcmpW(name,stde.pps_rawname))
                return n;
        if (stde.pps_prev != -1) {
                ret=STORAGE_look_for_named_pps(str,stde.pps_prev,name);
                if (ret!=-1)
                        return ret;
        }
        if (stde.pps_next != -1) {
                ret=STORAGE_look_for_named_pps(str,stde.pps_next,name);
                if (ret!=-1)
                        return ret;
        }
        return -1;
}

/******************************************************************************
 *              STORAGE_dump_pps_entry  [Internal]
 *
 * This function is there to simplify debugging. It is otherwise unused.
 */
void
STORAGE_dump_pps_entry(struct storage_pps_entry *stde) {
    char        name[33];

    WideCharToMultiByte( CP_ACP, 0, stde->pps_rawname, -1, name, sizeof(name), NULL, NULL);
        if (!stde->pps_sizeofname)
                return;
        TRACE("name: %s\n",name);
        TRACE("type: %d\n",stde->pps_type);
        TRACE("prev pps: %d\n",stde->pps_prev);
        TRACE("next pps: %d\n",stde->pps_next);
        TRACE("dir pps: %d\n",stde->pps_dir);
        TRACE("guid: %s\n",debugstr_guid(&(stde->pps_guid)));
        if (stde->pps_type !=2) {
                time_t  t;
                DWORD dw;
                RtlTimeToSecondsSince1970((LARGE_INTEGER *)&(stde->pps_ft1),&dw);
                t = dw;
                TRACE("ts1: %s\n",ctime(&t));
                RtlTimeToSecondsSince1970((LARGE_INTEGER *)&(stde->pps_ft2),&dw);
                t = dw;
                TRACE("ts2: %s\n",ctime(&t));
        }
        TRACE("startblock: %d\n",stde->pps_sb);
        TRACE("size: %d\n",stde->pps_size);
}

/******************************************************************************
 * STORAGE_init_storage [INTERNAL]
 */
static BOOL
STORAGE_init_storage(stream_access16 *str) {
        BYTE    block[BIGSIZE];
        LPDWORD bbs;
        struct storage_header *sth;
        struct storage_pps_entry *stde;
        DWORD result;

        if (str->hf)
            SetFilePointer( str->hf, 0, NULL, SEEK_SET );
        /* block -1 is the storage header */
        sth = (struct storage_header*)block;
        memcpy(sth->magic,STORAGE_magic,8);
        memset(sth->unknown1,0,sizeof(sth->unknown1));
        memset(sth->unknown2,0,sizeof(sth->unknown2));
        memset(sth->unknown3,0,sizeof(sth->unknown3));
        sth->num_of_bbd_blocks  = 1;
        sth->root_startblock    = 1;
        sth->sbd_startblock     = 0xffffffff;
        memset(sth->bbd_list,0xff,sizeof(sth->bbd_list));
        sth->bbd_list[0]        = 0;
        if (str->hf) {
            if (!WriteFile( str->hf, block, BIGSIZE, &result, NULL ) || result != BIGSIZE) return FALSE;
        } else {
            if (!_ilockbytes16_writeat(str->lockbytes, 0, BIGSIZE, block)) return FALSE;
        }
        /* block 0 is the big block directory */
        bbs=(LPDWORD)block;
        memset(block,0xff,sizeof(block)); /* mark all blocks as free */
        bbs[0]=STORAGE_CHAINENTRY_ENDOFCHAIN; /* for this block */
        bbs[1]=STORAGE_CHAINENTRY_ENDOFCHAIN; /* for directory entry */
        if (str->hf) {
            if (!WriteFile( str->hf, block, BIGSIZE, &result, NULL ) || result != BIGSIZE) return FALSE;
        } else {
            if (!_ilockbytes16_writeat(str->lockbytes, BIGSIZE, BIGSIZE, block)) return FALSE;
        }
        /* block 1 is the root directory entry */
        memset(block,0x00,sizeof(block));
        stde = (struct storage_pps_entry*)block;
        MultiByteToWideChar( CP_ACP, 0, "RootEntry", -1, stde->pps_rawname,
                             sizeof(stde->pps_rawname)/sizeof(WCHAR));
        stde->pps_sizeofname    = (strlenW(stde->pps_rawname)+1) * sizeof(WCHAR);
        stde->pps_type          = 5;
        stde->pps_dir           = -1;
        stde->pps_next          = -1;
        stde->pps_prev          = -1;
        stde->pps_sb            = 0xffffffff;
        stde->pps_size          = 0;
        if (str->hf) {
            return (WriteFile( str->hf, block, BIGSIZE, &result, NULL ) && result == BIGSIZE);
        } else {
            return _ilockbytes16_writeat(str->lockbytes, BIGSIZE, BIGSIZE, block);
        }
}

/******************************************************************************
 *              STORAGE_set_big_chain   [Internal]
 */
static BOOL
STORAGE_set_big_chain(stream_access16*str,int blocknr,INT type) {
        BYTE    block[BIGSIZE];
        LPINT   bbd = (LPINT)block;
        int     nextblocknr,bigblocknr;
        struct storage_header sth;
        BOOL ret;

        READ_HEADER(str);
        assert(blocknr!=type);
        while (blocknr>=0) {
                bigblocknr = sth.bbd_list[blocknr/128];
                assert(bigblocknr>=0);
                ret = STORAGE_get_big_block(str,bigblocknr,block);
                assert(ret);

                nextblocknr = bbd[blocknr&(128-1)];
                bbd[blocknr&(128-1)] = type;
                if (type>=0)
                        return TRUE;
                ret = STORAGE_put_big_block(str,bigblocknr,block);
                assert(ret);
                type = STORAGE_CHAINENTRY_FREE;
                blocknr = nextblocknr;
        }
        return TRUE;
}

/******************************************************************************
 * STORAGE_set_small_chain [Internal]
 */
static BOOL
STORAGE_set_small_chain(stream_access16*str,int blocknr,INT type) {
        BYTE    block[BIGSIZE];
        LPINT   sbd = (LPINT)block;
        int     lastblocknr,nextsmallblocknr,bigblocknr;
        struct storage_header sth;
        BOOL ret;

        READ_HEADER(str);

        assert(blocknr!=type);
        lastblocknr=-129;bigblocknr=-2;
        while (blocknr>=0) {
                /* cache block ... */
                if (lastblocknr/128!=blocknr/128) {
                        bigblocknr = STORAGE_get_nth_next_big_blocknr(str,sth.sbd_startblock,blocknr/128);
                        assert(bigblocknr>=0);
                        ret = STORAGE_get_big_block(str,bigblocknr,block);
                        assert(ret);
                }
                lastblocknr = blocknr;
                nextsmallblocknr = sbd[blocknr&(128-1)];
                sbd[blocknr&(128-1)] = type;
                ret = STORAGE_put_big_block(str,bigblocknr,block);
                assert(ret);
                if (type>=0)
                        return TRUE;
                type = STORAGE_CHAINENTRY_FREE;
                blocknr = nextsmallblocknr;
        }
        return TRUE;
}

/******************************************************************************
 *              STORAGE_get_free_big_blocknr    [Internal]
 */
static int
STORAGE_get_free_big_blocknr(stream_access16 *str) {
        BYTE    block[BIGSIZE];
        LPINT   sbd = (LPINT)block;
        int     lastbigblocknr,i,bigblocknr;
        unsigned int curblock;
        struct storage_header sth;
        BOOL ret;

        READ_HEADER(str);
        curblock        = 0;
        lastbigblocknr  = -1;
        bigblocknr      = sth.bbd_list[curblock];
        while (curblock<sth.num_of_bbd_blocks) {
                assert(bigblocknr>=0);
                ret = STORAGE_get_big_block(str,bigblocknr,block);
                assert(ret);
                for (i=0;i<128;i++)
                        if (sbd[i]==STORAGE_CHAINENTRY_FREE) {
                                sbd[i] = STORAGE_CHAINENTRY_ENDOFCHAIN;
                                ret = STORAGE_put_big_block(str,bigblocknr,block);
                                assert(ret);
                                memset(block,0x42,sizeof(block));
                                ret = STORAGE_put_big_block(str,i+curblock*128,block);
                                assert(ret);
                                return i+curblock*128;
                        }
                lastbigblocknr = bigblocknr;
                bigblocknr = sth.bbd_list[++curblock];
        }
        bigblocknr = curblock*128;
        /* since we have marked all blocks from 0 up to curblock*128-1
         * the next free one is curblock*128, where we happily put our
         * next large block depot.
         */
        memset(block,0xff,sizeof(block));
        /* mark the block allocated and returned by this function */
        sbd[1] = STORAGE_CHAINENTRY_ENDOFCHAIN;
        ret = STORAGE_put_big_block(str,bigblocknr,block);
        assert(ret);

        /* if we had a bbd block already (mostlikely) we need
         * to link the new one into the chain
         */
        if (lastbigblocknr!=-1) {
                ret = STORAGE_set_big_chain(str,lastbigblocknr,bigblocknr);
                assert(ret);
        }
        sth.bbd_list[curblock]=bigblocknr;
        sth.num_of_bbd_blocks++;
        assert(sth.num_of_bbd_blocks==curblock+1);
        ret = STORAGE_put_big_block(str,-1,(LPBYTE)&sth);
        assert(ret);

        /* Set the end of the chain for the bigblockdepots */
        ret = STORAGE_set_big_chain(str,bigblocknr,STORAGE_CHAINENTRY_ENDOFCHAIN);
        assert(ret);
        /* add 1, for the first entry is used for the additional big block
         * depot. (means we already used bigblocknr) */
        memset(block,0x42,sizeof(block));
        /* allocate this block (filled with 0x42) */
        ret = STORAGE_put_big_block(str,bigblocknr+1,block);
        assert(ret);
        return bigblocknr+1;
}


/******************************************************************************
 *              STORAGE_get_free_small_blocknr  [Internal]
 */
static int
STORAGE_get_free_small_blocknr(stream_access16 *str) {
        BYTE    block[BIGSIZE];
        LPINT   sbd = (LPINT)block;
        int     lastbigblocknr,newblocknr,i,curblock,bigblocknr;
        struct storage_pps_entry        root;
        struct storage_header sth;

        READ_HEADER(str);
        bigblocknr      = sth.sbd_startblock;
        curblock        = 0;
        lastbigblocknr  = -1;
        newblocknr      = -1;
        while (bigblocknr>=0) {
                if (!STORAGE_get_big_block(str,bigblocknr,block))
                        return -1;
                for (i=0;i<128;i++)
                        if (sbd[i]==STORAGE_CHAINENTRY_FREE) {
                                sbd[i]=STORAGE_CHAINENTRY_ENDOFCHAIN;
                                newblocknr = i+curblock*128;
                                break;
                        }
                if (i!=128)
                        break;
                lastbigblocknr = bigblocknr;
                bigblocknr = STORAGE_get_next_big_blocknr(str,bigblocknr);
                curblock++;
        }
        if (newblocknr==-1) {
                bigblocknr = STORAGE_get_free_big_blocknr(str);
                if (bigblocknr<0)
                        return -1;
                READ_HEADER(str);
                memset(block,0xff,sizeof(block));
                sbd[0]=STORAGE_CHAINENTRY_ENDOFCHAIN;
                if (!STORAGE_put_big_block(str,bigblocknr,block))
                        return -1;
                if (lastbigblocknr==-1) {
                        sth.sbd_startblock = bigblocknr;
                        if (!STORAGE_put_big_block(str,-1,(LPBYTE)&sth)) /* need to write it */
                                return -1;
                } else {
                        if (!STORAGE_set_big_chain(str,lastbigblocknr,bigblocknr))
                                return -1;
                }
                if (!STORAGE_set_big_chain(str,bigblocknr,STORAGE_CHAINENTRY_ENDOFCHAIN))
                        return -1;
                newblocknr = curblock*128;
        }
        /* allocate enough big blocks for storing the allocated small block */
        if (!STORAGE_get_root_pps_entry(str,&root))
                return -1;
        if (root.pps_sb==-1)
                lastbigblocknr  = -1;
        else
                lastbigblocknr  = STORAGE_get_nth_next_big_blocknr(str,root.pps_sb,(root.pps_size-1)/BIGSIZE);
        while (root.pps_size < (newblocknr*SMALLSIZE+SMALLSIZE-1)) {
                /* we need to allocate more stuff */
                bigblocknr = STORAGE_get_free_big_blocknr(str);
                if (bigblocknr<0)
                        return -1;
                READ_HEADER(str);
                if (root.pps_sb==-1) {
                        root.pps_sb      = bigblocknr;
                        root.pps_size   += BIGSIZE;
                } else {
                        if (!STORAGE_set_big_chain(str,lastbigblocknr,bigblocknr))
                                return -1;
                        root.pps_size   += BIGSIZE;
                }
                lastbigblocknr = bigblocknr;
        }
        if (!STORAGE_set_big_chain(str,lastbigblocknr,STORAGE_CHAINENTRY_ENDOFCHAIN))
                return -1;
        if (!STORAGE_put_pps_entry(str,0,&root))
                return -1;
        return newblocknr;
}

/******************************************************************************
 *              STORAGE_get_free_pps_entry      [Internal]
 */
static int
STORAGE_get_free_pps_entry(stream_access16*str) {
        int     blocknr, i, curblock, lastblocknr=-1;
        BYTE    block[BIGSIZE];
        struct storage_pps_entry *stde = (struct storage_pps_entry*)block;
        struct storage_header sth;

        READ_HEADER(str);
        blocknr = sth.root_startblock;
        assert(blocknr>=0);
        curblock=0;
        while (blocknr>=0) {
                if (!STORAGE_get_big_block(str,blocknr,block))
                        return -1;
                for (i=0;i<4;i++)
                        if (stde[i].pps_sizeofname==0) /* free */
                                return curblock*4+i;
                lastblocknr = blocknr;
                blocknr = STORAGE_get_next_big_blocknr(str,blocknr);
                curblock++;
        }
        assert(blocknr==STORAGE_CHAINENTRY_ENDOFCHAIN);
        blocknr = STORAGE_get_free_big_blocknr(str);
        /* sth invalidated */
        if (blocknr<0)
                return -1;

        if (!STORAGE_set_big_chain(str,lastblocknr,blocknr))
                return -1;
        if (!STORAGE_set_big_chain(str,blocknr,STORAGE_CHAINENTRY_ENDOFCHAIN))
                return -1;
        memset(block,0,sizeof(block));
        STORAGE_put_big_block(str,blocknr,block);
        return curblock*4;
}

/* --- IStream16 implementation */

typedef struct
{
        /* IUnknown fields */
        const IStream16Vtbl            *lpVtbl;
        LONG                            ref;
        /* IStream16 fields */
        SEGPTR                          thisptr; /* pointer to this struct as segmented */
        struct storage_pps_entry        stde;
        int                             ppsent;
        ULARGE_INTEGER                  offset;
        stream_access16                 str;
} IStream16Impl;

/******************************************************************************
 *              IStream16_QueryInterface        [STORAGE.518]
 */
HRESULT CDECL IStream16_fnQueryInterface(
        IStream16* iface,REFIID refiid,LPVOID *obj
) {
        IStream16Impl *This = (IStream16Impl *)iface;
        TRACE_(relay)("(%p)->(%s,%p)\n",This,debugstr_guid(refiid),obj);
        if (!memcmp(&IID_IUnknown,refiid,sizeof(IID_IUnknown))) {
                *obj = This;
                return 0;
        }
        return OLE_E_ENUM_NOMORE;

}

/******************************************************************************
 * IStream16_AddRef [STORAGE.519]
 */
ULONG CDECL IStream16_fnAddRef(IStream16* iface) {
        IStream16Impl *This = (IStream16Impl *)iface;
        return InterlockedIncrement(&This->ref);
}

static void
_ilockbytes16_addref(SEGPTR lockbytes) {
    DWORD args[1];
    HRESULT hres;

    args[0] = (DWORD)lockbytes; /* iface */
    if (!WOWCallback16Ex(
        (DWORD)((const ILockBytes16Vtbl*)MapSL(
                    (SEGPTR)((LPLOCKBYTES16)MapSL(lockbytes))->lpVtbl)
        )->AddRef,
        WCB16_PASCAL,
        1*sizeof(DWORD),
        (LPVOID)args,
        (LPDWORD)&hres
    ))
        ERR("CallTo16 ILockBytes16::AddRef() failed, hres %x\n",hres);
}

static void
_ilockbytes16_release(SEGPTR lockbytes) {
    DWORD args[1];
    HRESULT hres;

    args[0] = (DWORD)lockbytes; /* iface */
    if (!WOWCallback16Ex(
        (DWORD)((const ILockBytes16Vtbl*)MapSL(
                    (SEGPTR)((LPLOCKBYTES16)MapSL(lockbytes))->lpVtbl)
        )->Release,
        WCB16_PASCAL,
        1*sizeof(DWORD),
        (LPVOID)args,
        (LPDWORD)&hres
    ))
        ERR("CallTo16 ILockBytes16::Release() failed, hres %x\n",hres);
}

static void
_ilockbytes16_flush(SEGPTR lockbytes) {
    DWORD args[1];
    HRESULT hres;

    args[0] = (DWORD)lockbytes; /* iface */
    if (!WOWCallback16Ex(
        (DWORD)((const ILockBytes16Vtbl*)MapSL(
                    (SEGPTR)((LPLOCKBYTES16)MapSL(lockbytes))->lpVtbl)
        )->Flush,
        WCB16_PASCAL,
        1*sizeof(DWORD),
        (LPVOID)args,
        (LPDWORD)&hres
    ))
        ERR("CallTo16 ILockBytes16::Flush() failed, hres %x\n",hres);
}

/******************************************************************************
 * IStream16_Release [STORAGE.520]
 */
ULONG CDECL IStream16_fnRelease(IStream16* iface) {
        IStream16Impl *This = (IStream16Impl *)iface;
        ULONG ref;

        if (This->str.hf)
            FlushFileBuffers(This->str.hf);
        else
            _ilockbytes16_flush(This->str.lockbytes);
        ref = InterlockedDecrement(&This->ref);
        if (ref)
            return ref;

        if (This->str.hf)
            CloseHandle(This->str.hf);
        else
            _ilockbytes16_release(This->str.lockbytes);
        UnMapLS( This->thisptr );
        HeapFree( GetProcessHeap(), 0, This );
        return 0;
}

/******************************************************************************
 *              IStream16_Seek  [STORAGE.523]
 *
 * FIXME
 *    Does not handle 64 bits
 */
HRESULT CDECL IStream16_fnSeek(
        IStream16* iface,LARGE_INTEGER offset,DWORD whence,ULARGE_INTEGER *newpos
) {
        IStream16Impl *This = (IStream16Impl *)iface;
        TRACE_(relay)("(%p)->([%d.%d],%d,%p)\n",This,offset.u.HighPart,offset.u.LowPart,whence,newpos);

        switch (whence) {
        /* unix SEEK_xx should be the same as win95 ones */
        case SEEK_SET:
                /* offset must be ==0 (<0 is invalid, and >0 cannot be handled
                 * right now.
                 */
                assert(offset.u.HighPart==0);
                This->offset.u.HighPart = offset.u.HighPart;
                This->offset.u.LowPart = offset.u.LowPart;
                break;
        case SEEK_CUR:
                if (offset.u.HighPart < 0) {
                        /* FIXME: is this negation correct ? */
                        offset.u.HighPart = -offset.u.HighPart;
                        offset.u.LowPart = (0xffffffff ^ offset.u.LowPart)+1;

                        assert(offset.u.HighPart==0);
                        assert(This->offset.u.LowPart >= offset.u.LowPart);
                        This->offset.u.LowPart -= offset.u.LowPart;
                } else {
                        assert(offset.u.HighPart==0);
                        This->offset.u.LowPart+= offset.u.LowPart;
                }
                break;
        case SEEK_END:
                assert(offset.u.HighPart==0);
                This->offset.u.LowPart = This->stde.pps_size-offset.u.LowPart;
                break;
        }
        if (This->offset.u.LowPart>This->stde.pps_size)
                This->offset.u.LowPart=This->stde.pps_size;
        if (newpos) *newpos = This->offset;
        return S_OK;
}

/******************************************************************************
 *              IStream16_Read  [STORAGE.521]
 */
HRESULT CDECL IStream16_fnRead(
        IStream16* iface,void  *pv,ULONG cb,ULONG  *pcbRead
) {
        IStream16Impl *This = (IStream16Impl *)iface;
        BYTE    block[BIGSIZE];
        ULONG   *bytesread=pcbRead,xxread;
        int     blocknr;
        LPBYTE  pbv = pv;

        TRACE_(relay)("(%p)->(%p,%d,%p)\n",This,pv,cb,pcbRead);
        if (!pcbRead) bytesread=&xxread;
        *bytesread = 0;

        if (cb>This->stde.pps_size-This->offset.u.LowPart)
                cb=This->stde.pps_size-This->offset.u.LowPart;
        if (This->stde.pps_size < 0x1000) {
                /* use small block reader */
                blocknr = STORAGE_get_nth_next_small_blocknr(&This->str,This->stde.pps_sb,This->offset.u.LowPart/SMALLSIZE);
                while (cb) {
                        unsigned int cc;

                        if (!STORAGE_get_small_block(&This->str,blocknr,block)) {
                           WARN("small block read failed!!!\n");
                                return E_FAIL;
                        }
                        cc = cb;
                        if (cc>SMALLSIZE-(This->offset.u.LowPart&(SMALLSIZE-1)))
                                cc=SMALLSIZE-(This->offset.u.LowPart&(SMALLSIZE-1));
                        memcpy(pbv,block+(This->offset.u.LowPart&(SMALLSIZE-1)),cc);
                        This->offset.u.LowPart+=cc;
                        pbv+=cc;
                        *bytesread+=cc;
                        cb-=cc;
                        blocknr = STORAGE_get_next_small_blocknr(&This->str,blocknr);
                }
        } else {
                /* use big block reader */
                blocknr = STORAGE_get_nth_next_big_blocknr(&This->str,This->stde.pps_sb,This->offset.u.LowPart/BIGSIZE);
                while (cb) {
                        unsigned int cc;

                        if (!STORAGE_get_big_block(&This->str,blocknr,block)) {
                                WARN("big block read failed!!!\n");
                                return E_FAIL;
                        }
                        cc = cb;
                        if (cc>BIGSIZE-(This->offset.u.LowPart&(BIGSIZE-1)))
                                cc=BIGSIZE-(This->offset.u.LowPart&(BIGSIZE-1));
                        memcpy(pbv,block+(This->offset.u.LowPart&(BIGSIZE-1)),cc);
                        This->offset.u.LowPart+=cc;
                        pbv+=cc;
                        *bytesread+=cc;
                        cb-=cc;
                        blocknr=STORAGE_get_next_big_blocknr(&This->str,blocknr);
                }
        }
        return S_OK;
}

/******************************************************************************
 *              IStream16_Write [STORAGE.522]
 */
HRESULT CDECL IStream16_fnWrite(
        IStream16* iface,const void *pv,ULONG cb,ULONG *pcbWrite
) {
        IStream16Impl *This = (IStream16Impl *)iface;
        BYTE    block[BIGSIZE];
        ULONG   *byteswritten=pcbWrite,xxwritten;
        int     oldsize,newsize,i,curoffset=0,lastblocknr,blocknr,cc;
        const BYTE* pbv = pv;

        if (!pcbWrite) byteswritten=&xxwritten;
        *byteswritten = 0;

        TRACE_(relay)("(%p)->(%p,%d,%p)\n",This,pv,cb,pcbWrite);
        /* do we need to junk some blocks? */
        newsize = This->offset.u.LowPart+cb;
        oldsize = This->stde.pps_size;
        if (newsize < oldsize) {
                if (oldsize < 0x1000) {
                        /* only small blocks */
                        blocknr=STORAGE_get_nth_next_small_blocknr(&This->str,This->stde.pps_sb,newsize/SMALLSIZE);

                        assert(blocknr>=0);

                        /* will set the rest of the chain to 'free' */
                        if (!STORAGE_set_small_chain(&This->str,blocknr,STORAGE_CHAINENTRY_ENDOFCHAIN))
                                return E_FAIL;
                } else {
                        if (newsize >= 0x1000) {
                                blocknr=STORAGE_get_nth_next_big_blocknr(&This->str,This->stde.pps_sb,newsize/BIGSIZE);
                                assert(blocknr>=0);

                                /* will set the rest of the chain to 'free' */
                                if (!STORAGE_set_big_chain(&This->str,blocknr,STORAGE_CHAINENTRY_ENDOFCHAIN))
                                        return E_FAIL;
                        } else {
                                /* Migrate large blocks to small blocks
                                 * (we just migrate newsize bytes)
                                 */
                                LPBYTE  curdata,data = HeapAlloc(GetProcessHeap(),0,newsize+BIGSIZE);
                                HRESULT r = E_FAIL;

                                cc      = newsize;
                                blocknr = This->stde.pps_sb;
                                curdata = data;
                                while (cc>0) {
                                        if (!STORAGE_get_big_block(&This->str,blocknr,curdata)) {
                                                HeapFree(GetProcessHeap(),0,data);
                                                return E_FAIL;
                                        }
                                        curdata += BIGSIZE;
                                        cc      -= BIGSIZE;
                                        blocknr  = STORAGE_get_next_big_blocknr(&This->str,blocknr);
                                }
                                /* frees complete chain for this stream */
                                if (!STORAGE_set_big_chain(&This->str,This->stde.pps_sb,STORAGE_CHAINENTRY_FREE))
                                        goto err;
                                curdata = data;
                                blocknr = This->stde.pps_sb = STORAGE_get_free_small_blocknr(&This->str);
                                if (blocknr<0)
                                        goto err;
                                cc      = newsize;
                                while (cc>0) {
                                        if (!STORAGE_put_small_block(&This->str,blocknr,curdata))
                                                goto err;
                                        cc      -= SMALLSIZE;
                                        if (cc<=0) {
                                                if (!STORAGE_set_small_chain(&This->str,blocknr,STORAGE_CHAINENTRY_ENDOFCHAIN))
                                                        goto err;
                                                break;
                                        } else {
                                                int newblocknr = STORAGE_get_free_small_blocknr(&This->str);
                                                if (newblocknr<0)
                                                        goto err;
                                                if (!STORAGE_set_small_chain(&This->str,blocknr,newblocknr))
                                                        goto err;
                                                blocknr = newblocknr;
                                        }
                                        curdata += SMALLSIZE;
                                }
                                r = S_OK;
                        err:
                                HeapFree(GetProcessHeap(),0,data);
                                if(r != S_OK)
                                        return r;
                        }
                }
                This->stde.pps_size = newsize;
        }

        if (newsize > oldsize) {
                if (oldsize >= 0x1000) {
                        /* should return the block right before the 'endofchain' */
                        blocknr = STORAGE_get_nth_next_big_blocknr(&This->str,This->stde.pps_sb,This->stde.pps_size/BIGSIZE);
                        assert(blocknr>=0);
                        lastblocknr     = blocknr;
                        for (i=oldsize/BIGSIZE;i<newsize/BIGSIZE;i++) {
                                blocknr = STORAGE_get_free_big_blocknr(&This->str);
                                if (blocknr<0)
                                        return E_FAIL;
                                if (!STORAGE_set_big_chain(&This->str,lastblocknr,blocknr))
                                        return E_FAIL;
                                lastblocknr = blocknr;
                        }
                        if (!STORAGE_set_big_chain(&This->str,blocknr,STORAGE_CHAINENTRY_ENDOFCHAIN))
                                return E_FAIL;
                } else {
                        if (newsize < 0x1000) {
                                /* find startblock */
                                if (!oldsize)
                                        This->stde.pps_sb = blocknr = STORAGE_get_free_small_blocknr(&This->str);
                                else
                                        blocknr = STORAGE_get_nth_next_small_blocknr(&This->str,This->stde.pps_sb,This->stde.pps_size/SMALLSIZE);
                                if (blocknr<0)
                                        return E_FAIL;

                                /* allocate required new small blocks */
                                lastblocknr = blocknr;
                                for (i=oldsize/SMALLSIZE;i<newsize/SMALLSIZE;i++) {
                                        blocknr = STORAGE_get_free_small_blocknr(&This->str);
                                        if (blocknr<0)
                                                return E_FAIL;
                                        if (!STORAGE_set_small_chain(&This->str,lastblocknr,blocknr))
                                                return E_FAIL;
                                        lastblocknr = blocknr;
                                }
                                /* and terminate the chain */
                                if (!STORAGE_set_small_chain(&This->str,lastblocknr,STORAGE_CHAINENTRY_ENDOFCHAIN))
                                        return E_FAIL;
                        } else {
                                if (!oldsize) {
                                        /* no single block allocated yet */
                                        blocknr=STORAGE_get_free_big_blocknr(&This->str);
                                        if (blocknr<0)
                                                return E_FAIL;
                                        This->stde.pps_sb = blocknr;
                                } else {
                                        /* Migrate small blocks to big blocks */
                                        LPBYTE  curdata,data = HeapAlloc(GetProcessHeap(),0,oldsize+BIGSIZE);
                                        HRESULT r = E_FAIL;

                                        cc      = oldsize;
                                        blocknr = This->stde.pps_sb;
                                        curdata = data;
                                        /* slurp in */
                                        while (cc>0) {
                                                if (!STORAGE_get_small_block(&This->str,blocknr,curdata))
                                                        goto err2;
                                                curdata += SMALLSIZE;
                                                cc      -= SMALLSIZE;
                                                blocknr  = STORAGE_get_next_small_blocknr(&This->str,blocknr);
                                        }
                                        /* free small block chain */
                                        if (!STORAGE_set_small_chain(&This->str,This->stde.pps_sb,STORAGE_CHAINENTRY_FREE))
                                                goto err2;
                                        curdata = data;
                                        blocknr = This->stde.pps_sb = STORAGE_get_free_big_blocknr(&This->str);
                                        if (blocknr<0)
                                                goto err2;
                                        /* put the data into the big blocks */
                                        cc      = This->stde.pps_size;
                                        while (cc>0) {
                                                if (!STORAGE_put_big_block(&This->str,blocknr,curdata))
                                                        goto err2;
                                                cc      -= BIGSIZE;
                                                if (cc<=0) {
                                                        if (!STORAGE_set_big_chain(&This->str,blocknr,STORAGE_CHAINENTRY_ENDOFCHAIN))
                                                                goto err2;
                                                        break;
                                                } else {
                                                        int newblocknr = STORAGE_get_free_big_blocknr(&This->str);
                                                        if (newblocknr<0)
                                                                goto err2;
                                                        if (!STORAGE_set_big_chain(&This->str,blocknr,newblocknr))
                                                                goto err2;
                                                        blocknr = newblocknr;
                                                }
                                                curdata += BIGSIZE;
                                        }
                                        r = S_OK;
                                err2:
                                        HeapFree(GetProcessHeap(),0,data);
                                        if(r != S_OK)
                                                return r;
                                }
                                /* generate big blocks to fit the new data */
                                lastblocknr     = blocknr;
                                for (i=oldsize/BIGSIZE;i<newsize/BIGSIZE;i++) {
                                        blocknr = STORAGE_get_free_big_blocknr(&This->str);
                                        if (blocknr<0)
                                                return E_FAIL;
                                        if (!STORAGE_set_big_chain(&This->str,lastblocknr,blocknr))
                                                return E_FAIL;
                                        lastblocknr = blocknr;
                                }
                                /* terminate chain */
                                if (!STORAGE_set_big_chain(&This->str,lastblocknr,STORAGE_CHAINENTRY_ENDOFCHAIN))
                                        return E_FAIL;
                        }
                }
                This->stde.pps_size = newsize;
        }

        /* There are just some cases where we didn't modify it, we write it out
         * everytime
         */
        if (!STORAGE_put_pps_entry(&This->str,This->ppsent,&(This->stde)))
                return E_FAIL;

        /* finally the write pass */
        if (This->stde.pps_size < 0x1000) {
                blocknr = STORAGE_get_nth_next_small_blocknr(&This->str,This->stde.pps_sb,This->offset.u.LowPart/SMALLSIZE);
                assert(blocknr>=0);
                while (cb>0) {
                        /* we ensured that it is allocated above */
                        assert(blocknr>=0);
                        /* Read old block everytime, since we can have
                         * overlapping data at START and END of the write
                         */
                        if (!STORAGE_get_small_block(&This->str,blocknr,block))
                                return E_FAIL;

                        cc = SMALLSIZE-(This->offset.u.LowPart&(SMALLSIZE-1));
                        if (cc>cb)
                                cc=cb;
                        memcpy( ((LPBYTE)block)+(This->offset.u.LowPart&(SMALLSIZE-1)),
                                pbv+curoffset,
                                cc
                        );
                        if (!STORAGE_put_small_block(&This->str,blocknr,block))
                                return E_FAIL;
                        cb                      -= cc;
                        curoffset               += cc;
                        pbv                     += cc;
                        This->offset.u.LowPart  += cc;
                        *byteswritten           += cc;
                        blocknr = STORAGE_get_next_small_blocknr(&This->str,blocknr);
                }
        } else {
                blocknr = STORAGE_get_nth_next_big_blocknr(&This->str,This->stde.pps_sb,This->offset.u.LowPart/BIGSIZE);
                assert(blocknr>=0);
                while (cb>0) {
                        /* we ensured that it is allocated above, so it better is */
                        assert(blocknr>=0);
                        /* read old block everytime, since we can have
                         * overlapping data at START and END of the write
                         */
                        if (!STORAGE_get_big_block(&This->str,blocknr,block))
                                return E_FAIL;

                        cc = BIGSIZE-(This->offset.u.LowPart&(BIGSIZE-1));
                        if (cc>cb)
                                cc=cb;
                        memcpy( ((LPBYTE)block)+(This->offset.u.LowPart&(BIGSIZE-1)),
                                pbv+curoffset,
                                cc
                        );
                        if (!STORAGE_put_big_block(&This->str,blocknr,block))
                                return E_FAIL;
                        cb                      -= cc;
                        curoffset               += cc;
                        pbv                     += cc;
                        This->offset.u.LowPart  += cc;
                        *byteswritten           += cc;
                        blocknr = STORAGE_get_next_big_blocknr(&This->str,blocknr);
                }
        }
        return S_OK;
}

/******************************************************************************
 *              _create_istream16       [Internal]
 */
static void _create_istream16(LPSTREAM16 *str) {
        IStream16Impl*  lpst;

        if (!strvt16.QueryInterface) {
                HMODULE16       wp = GetModuleHandle16("STORAGE");
                if (wp>=32) {
                  /* FIXME: what is This GetProcAddress16. Should the name be IStream16_QueryInterface of IStream16_fnQueryInterface */
#define VTENT(xfn)  strvt16.xfn = (void*)GetProcAddress16(wp,"IStream16_"#xfn);assert(strvt16.xfn)
                        VTENT(QueryInterface);
                        VTENT(AddRef);
                        VTENT(Release);
                        VTENT(Read);
                        VTENT(Write);
                        VTENT(Seek);
                        VTENT(SetSize);
                        VTENT(CopyTo);
                        VTENT(Commit);
                        VTENT(Revert);
                        VTENT(LockRegion);
                        VTENT(UnlockRegion);
                        VTENT(Stat);
                        VTENT(Clone);
#undef VTENT
                        segstrvt16 = (const IStream16Vtbl*)MapLS( &strvt16 );
                } else {
#define VTENT(xfn) strvt16.xfn = IStream16_fn##xfn;
                        VTENT(QueryInterface);
                        VTENT(AddRef);
                        VTENT(Release);
                        VTENT(Read);
                        VTENT(Write);
                        VTENT(Seek);
        /*
                        VTENT(CopyTo);
                        VTENT(Commit);
                        VTENT(SetSize);
                        VTENT(Revert);
                        VTENT(LockRegion);
                        VTENT(UnlockRegion);
                        VTENT(Stat);
                        VTENT(Clone);
        */
#undef VTENT
                        segstrvt16 = &strvt16;
                }
        }
        lpst = HeapAlloc( GetProcessHeap(), 0, sizeof(*lpst) );
        lpst->lpVtbl    = segstrvt16;
        lpst->ref       = 1;
        lpst->thisptr   = MapLS( lpst );
        lpst->str.hf    = NULL;
        lpst->str.lockbytes     = 0;
        *str = (void*)lpst->thisptr;
}


/* --- IStream32 implementation */

typedef struct
{
        /* IUnknown fields */
        const IStreamVtbl              *lpVtbl;
        LONG                            ref;
        /* IStream32 fields */
        struct storage_pps_entry        stde;
        int                             ppsent;
        HANDLE                          hf;
        ULARGE_INTEGER                  offset;
} IStream32Impl;

/******************************************************************************
 *              IStorage16_QueryInterface       [STORAGE.500]
 */
HRESULT CDECL IStorage16_fnQueryInterface(
        IStorage16* iface,REFIID refiid,LPVOID *obj
) {
        IStorage16Impl *This = (IStorage16Impl *)iface;

        TRACE_(relay)("(%p)->(%s,%p)\n",This,debugstr_guid(refiid),obj);

        if (!memcmp(&IID_IUnknown,refiid,sizeof(IID_IUnknown))) {
                *obj = This;
                return 0;
        }
        return OLE_E_ENUM_NOMORE;
}

/******************************************************************************
 * IStorage16_AddRef [STORAGE.501]
 */
ULONG CDECL IStorage16_fnAddRef(IStorage16* iface) {
        IStorage16Impl *This = (IStorage16Impl *)iface;
        return InterlockedIncrement(&This->ref);
}

/******************************************************************************
 * IStorage16_Release [STORAGE.502]
 */
ULONG CDECL IStorage16_fnRelease(IStorage16* iface) {
        IStorage16Impl *This = (IStorage16Impl *)iface;
        ULONG ref;
        ref = InterlockedDecrement(&This->ref);
        if (!ref)
        {
            UnMapLS( This->thisptr );
            HeapFree( GetProcessHeap(), 0, This );
        }
        return ref;
}

/******************************************************************************
 * IStorage16_Stat [STORAGE.517]
 */
HRESULT CDECL IStorage16_fnStat(
        LPSTORAGE16 iface,STATSTG16 *pstatstg, DWORD grfStatFlag
) {
        IStorage16Impl *This = (IStorage16Impl *)iface;
        DWORD len = WideCharToMultiByte( CP_ACP, 0, This->stde.pps_rawname, -1, NULL, 0, NULL, NULL );
        LPSTR nameA = HeapAlloc( GetProcessHeap(), 0, len );

        TRACE("(%p)->(%p,0x%08x)\n",
                This,pstatstg,grfStatFlag
        );
        WideCharToMultiByte( CP_ACP, 0, This->stde.pps_rawname, -1, nameA, len, NULL, NULL );
        pstatstg->pwcsName=(LPOLESTR16)MapLS( nameA );
        pstatstg->type = This->stde.pps_type;
        pstatstg->cbSize.u.LowPart = This->stde.pps_size;
        pstatstg->mtime = This->stde.pps_ft1; /* FIXME */ /* why? */
        pstatstg->atime = This->stde.pps_ft2; /* FIXME */
        pstatstg->ctime = This->stde.pps_ft2; /* FIXME */
        pstatstg->grfMode       = 0; /* FIXME */
        pstatstg->grfLocksSupported = 0; /* FIXME */
        pstatstg->clsid         = This->stde.pps_guid;
        pstatstg->grfStateBits  = 0; /* FIXME */
        pstatstg->reserved      = 0;
        return S_OK;
}

/******************************************************************************
 *              IStorage16_Commit       [STORAGE.509]
 */
HRESULT CDECL IStorage16_fnCommit(
        LPSTORAGE16 iface,DWORD commitflags
) {
        IStorage16Impl *This = (IStorage16Impl *)iface;
        FIXME("(%p)->(0x%08x),STUB!\n",
                This,commitflags
        );
        return S_OK;
}

/******************************************************************************
 * IStorage16_CopyTo [STORAGE.507]
 */
HRESULT CDECL IStorage16_fnCopyTo(LPSTORAGE16 iface,DWORD ciidExclude,const IID *rgiidExclude,SNB16 SNB16Exclude,IStorage16 *pstgDest) {
        IStorage16Impl *This = (IStorage16Impl *)iface;
        FIXME("IStorage16(%p)->(0x%08x,%s,%p,%p),stub!\n",
                This,ciidExclude,debugstr_guid(rgiidExclude),SNB16Exclude,pstgDest
        );
        return S_OK;
}


/******************************************************************************
 * IStorage16_CreateStorage [STORAGE.505]
 */
HRESULT CDECL IStorage16_fnCreateStorage(
        LPSTORAGE16 iface,LPCOLESTR16 pwcsName,DWORD grfMode,DWORD dwStgFormat,DWORD reserved2, IStorage16 **ppstg
) {
        IStorage16Impl *This = (IStorage16Impl *)iface;
        IStorage16Impl* lpstg;
        int             ppsent,x;
        struct storage_pps_entry        stde;
        struct storage_header sth;
        BOOL ret;
        int      nPPSEntries;

        READ_HEADER(&This->str);
        TRACE("(%p)->(%s,0x%08x,0x%08x,0x%08x,%p)\n",
                This,pwcsName,grfMode,dwStgFormat,reserved2,ppstg
        );
        if (grfMode & STGM_TRANSACTED)
                FIXME("We do not support transacted Compound Storage. Using direct mode.\n");
        _create_istorage16(ppstg);
        lpstg = MapSL((SEGPTR)*ppstg);
        if (This->str.hf) {
            DuplicateHandle( GetCurrentProcess(), This->str.hf, GetCurrentProcess(),
                             &lpstg->str.hf, 0, TRUE, DUPLICATE_SAME_ACCESS );
        } else {
            lpstg->str.lockbytes = This->str.lockbytes;
            _ilockbytes16_addref(This->str.lockbytes);
        }

        ppsent=STORAGE_get_free_pps_entry(&lpstg->str);
        if (ppsent<0)
                return E_FAIL;
        stde=This->stde;
        if (stde.pps_dir==-1) {
                stde.pps_dir = ppsent;
                x = This->ppsent;
        } else {
                FIXME(" use prev chain too ?\n");
                x=stde.pps_dir;
                if (1!=STORAGE_get_pps_entry(&lpstg->str,x,&stde))
                        return E_FAIL;
                while (stde.pps_next!=-1) {
                        x=stde.pps_next;
                        if (1!=STORAGE_get_pps_entry(&lpstg->str,x,&stde))
                                return E_FAIL;
                }
                stde.pps_next = ppsent;
        }
        ret = STORAGE_put_pps_entry(&lpstg->str,x,&stde);
        assert(ret);
        nPPSEntries = STORAGE_get_pps_entry(&lpstg->str,ppsent,&(lpstg->stde));
        assert(nPPSEntries == 1);
        MultiByteToWideChar( CP_ACP, 0, pwcsName, -1, lpstg->stde.pps_rawname,
                             sizeof(lpstg->stde.pps_rawname)/sizeof(WCHAR));
        lpstg->stde.pps_sizeofname = (strlenW(lpstg->stde.pps_rawname)+1)*sizeof(WCHAR);
        lpstg->stde.pps_next    = -1;
        lpstg->stde.pps_prev    = -1;
        lpstg->stde.pps_dir     = -1;
        lpstg->stde.pps_sb      = -1;
        lpstg->stde.pps_size    =  0;
        lpstg->stde.pps_type    =  1;
        lpstg->ppsent           = ppsent;
        /* FIXME: timestamps? */
        if (!STORAGE_put_pps_entry(&lpstg->str,ppsent,&(lpstg->stde)))
                return E_FAIL;
        return S_OK;
}

/******************************************************************************
 *              IStorage16_CreateStream [STORAGE.503]
 */
HRESULT CDECL IStorage16_fnCreateStream(
        LPSTORAGE16 iface,LPCOLESTR16 pwcsName,DWORD grfMode,DWORD reserved1,DWORD reserved2, IStream16 **ppstm
) {
        IStorage16Impl *This = (IStorage16Impl *)iface;
        IStream16Impl*  lpstr;
        int             ppsent,x;
        struct storage_pps_entry        stde;
        BOOL ret;
        int      nPPSEntries;

        TRACE("(%p)->(%s,0x%08x,0x%08x,0x%08x,%p)\n",
                This,pwcsName,grfMode,reserved1,reserved2,ppstm
        );
        if (grfMode & STGM_TRANSACTED)
                FIXME("We do not support transacted Compound Storage. Using direct mode.\n");
        _create_istream16(ppstm);
        lpstr = MapSL((SEGPTR)*ppstm);
        if (This->str.hf) {
            DuplicateHandle( GetCurrentProcess(), This->str.hf, GetCurrentProcess(),
                             &lpstr->str.hf, 0, TRUE, DUPLICATE_SAME_ACCESS );
        } else {
            lpstr->str.lockbytes = This->str.lockbytes;
            _ilockbytes16_addref(This->str.lockbytes);
        }
        lpstr->offset.u.LowPart = 0;
        lpstr->offset.u.HighPart= 0;

        ppsent=STORAGE_get_free_pps_entry(&lpstr->str);
        if (ppsent<0)
                return E_FAIL;
        stde=This->stde;
        if (stde.pps_next==-1)
                x=This->ppsent;
        else
                while (stde.pps_next!=-1) {
                        x=stde.pps_next;
                        if (1!=STORAGE_get_pps_entry(&lpstr->str,x,&stde))
                                return E_FAIL;
                }
        stde.pps_next = ppsent;
        ret = STORAGE_put_pps_entry(&lpstr->str,x,&stde);
        assert(ret);
        nPPSEntries = STORAGE_get_pps_entry(&lpstr->str,ppsent,&(lpstr->stde));
        assert(nPPSEntries == 1);
        MultiByteToWideChar( CP_ACP, 0, pwcsName, -1, lpstr->stde.pps_rawname,
                             sizeof(lpstr->stde.pps_rawname)/sizeof(WCHAR));
        lpstr->stde.pps_sizeofname = (strlenW(lpstr->stde.pps_rawname)+1) * sizeof(WCHAR);
        lpstr->stde.pps_next    = -1;
        lpstr->stde.pps_prev    = -1;
        lpstr->stde.pps_dir     = -1;
        lpstr->stde.pps_sb      = -1;
        lpstr->stde.pps_size    =  0;
        lpstr->stde.pps_type    =  2;
        lpstr->ppsent           = ppsent;

        /* FIXME: timestamps? */
        if (!STORAGE_put_pps_entry(&lpstr->str,ppsent,&(lpstr->stde)))
                return E_FAIL;
        return S_OK;
}

/******************************************************************************
 *              IStorage16_OpenStorage  [STORAGE.506]
 */
HRESULT CDECL IStorage16_fnOpenStorage(
        LPSTORAGE16 iface,LPCOLESTR16 pwcsName, IStorage16 *pstgPrio, DWORD grfMode, SNB16 snbExclude, DWORD reserved, IStorage16 **ppstg
) {
        IStorage16Impl *This = (IStorage16Impl *)iface;
        IStream16Impl*  lpstg;
        WCHAR           name[33];
        int             newpps;

        TRACE("(%p)->(%s,%p,0x%08x,%p,0x%08x,%p)\n",
                This,pwcsName,pstgPrio,grfMode,snbExclude,reserved,ppstg
        );
        if (grfMode & STGM_TRANSACTED)
                FIXME("We do not support transacted Compound Storage. Using direct mode.\n");
        _create_istorage16(ppstg);
        lpstg = MapSL((SEGPTR)*ppstg);
        if (This->str.hf) {
            DuplicateHandle( GetCurrentProcess(), This->str.hf, GetCurrentProcess(),
                             &lpstg->str.hf, 0, TRUE, DUPLICATE_SAME_ACCESS );
        } else {
            lpstg->str.lockbytes = This->str.lockbytes;
            _ilockbytes16_addref(This->str.lockbytes);
        }
        MultiByteToWideChar( CP_ACP, 0, pwcsName, -1, name, sizeof(name)/sizeof(WCHAR));
        newpps = STORAGE_look_for_named_pps(&lpstg->str,This->stde.pps_dir,name);
        if (newpps==-1) {
                IStream16_fnRelease((IStream16*)lpstg);
                return E_FAIL;
        }

        if (1!=STORAGE_get_pps_entry(&lpstg->str,newpps,&(lpstg->stde))) {
                IStream16_fnRelease((IStream16*)lpstg);
                return E_FAIL;
        }
        lpstg->ppsent           = newpps;
        return S_OK;
}

/******************************************************************************
 * IStorage16_OpenStream [STORAGE.504]
 */
HRESULT CDECL IStorage16_fnOpenStream(
        LPSTORAGE16 iface,LPCOLESTR16 pwcsName, void *reserved1, DWORD grfMode, DWORD reserved2, IStream16 **ppstm
) {
        IStorage16Impl *This = (IStorage16Impl *)iface;
        IStream16Impl*  lpstr;
        WCHAR           name[33];
        int             newpps;

        TRACE("(%p)->(%s,%p,0x%08x,0x%08x,%p)\n",
                This,pwcsName,reserved1,grfMode,reserved2,ppstm
        );
        if (grfMode & STGM_TRANSACTED)
                FIXME("We do not support transacted Compound Storage. Using direct mode.\n");
        _create_istream16(ppstm);
        lpstr = MapSL((SEGPTR)*ppstm);
        if (This->str.hf) {
            DuplicateHandle( GetCurrentProcess(), This->str.hf, GetCurrentProcess(),
                             &lpstr->str.hf, 0, TRUE, DUPLICATE_SAME_ACCESS );
        } else {
            lpstr->str.lockbytes = This->str.lockbytes;
            _ilockbytes16_addref(This->str.lockbytes);
        }
        MultiByteToWideChar( CP_ACP, 0, pwcsName, -1, name, sizeof(name)/sizeof(WCHAR));
        newpps = STORAGE_look_for_named_pps(&lpstr->str,This->stde.pps_dir,name);
        if (newpps==-1) {
                IStream16_fnRelease((IStream16*)lpstr);
                return E_FAIL;
        }

        if (1!=STORAGE_get_pps_entry(&lpstr->str,newpps,&(lpstr->stde))) {
                IStream16_fnRelease((IStream16*)lpstr);
                return E_FAIL;
        }
        lpstr->offset.u.LowPart         = 0;
        lpstr->offset.u.HighPart        = 0;
        lpstr->ppsent                   = newpps;
        return S_OK;
}

/******************************************************************************
 * _create_istorage16 [INTERNAL]
 */
static void _create_istorage16(LPSTORAGE16 *stg) {
        IStorage16Impl* lpst;

        if (!stvt16.QueryInterface) {
                HMODULE16       wp = GetModuleHandle16("STORAGE");
                if (wp>=32) {
#define VTENT(xfn)  stvt16.xfn = (void*)GetProcAddress16(wp,"IStorage16_"#xfn);
                        VTENT(QueryInterface)
                        VTENT(AddRef)
                        VTENT(Release)
                        VTENT(CreateStream)
                        VTENT(OpenStream)
                        VTENT(CreateStorage)
                        VTENT(OpenStorage)
                        VTENT(CopyTo)
                        VTENT(MoveElementTo)
                        VTENT(Commit)
                        VTENT(Revert)
                        VTENT(EnumElements)
                        VTENT(DestroyElement)
                        VTENT(RenameElement)
                        VTENT(SetElementTimes)
                        VTENT(SetClass)
                        VTENT(SetStateBits)
                        VTENT(Stat)
#undef VTENT
                        segstvt16 = (const IStorage16Vtbl*)MapLS( &stvt16 );
                } else {
#define VTENT(xfn) stvt16.xfn = IStorage16_fn##xfn;
                        VTENT(QueryInterface)
                        VTENT(AddRef)
                        VTENT(Release)
                        VTENT(CreateStream)
                        VTENT(OpenStream)
                        VTENT(CreateStorage)
                        VTENT(OpenStorage)
                        VTENT(CopyTo)
                        VTENT(Commit)
        /*  not (yet) implemented ...
                        VTENT(MoveElementTo)
                        VTENT(Revert)
                        VTENT(EnumElements)
                        VTENT(DestroyElement)
                        VTENT(RenameElement)
                        VTENT(SetElementTimes)
                        VTENT(SetClass)
                        VTENT(SetStateBits)
                        VTENT(Stat)
        */
#undef VTENT
                        segstvt16 = &stvt16;
                }
        }
        lpst = HeapAlloc( GetProcessHeap(), 0, sizeof(*lpst) );
        lpst->lpVtbl    = segstvt16;
        lpst->str.hf    = NULL;
        lpst->str.lockbytes     = 0;
        lpst->ref       = 1;
        lpst->thisptr   = MapLS(lpst);
        *stg = (void*)lpst->thisptr;
}

/******************************************************************************
 *      Storage API functions
 */

/******************************************************************************
 *              StgCreateDocFileA       [STORAGE.1]
 */
HRESULT WINAPI StgCreateDocFile16(
        LPCOLESTR16 pwcsName,DWORD grfMode,DWORD reserved,IStorage16 **ppstgOpen
) {
        HANDLE          hf;
        int             i,ret;
        IStorage16Impl* lpstg;
        struct storage_pps_entry        stde;

        TRACE("(%s,0x%08x,0x%08x,%p)\n",
                pwcsName,grfMode,reserved,ppstgOpen
        );
        _create_istorage16(ppstgOpen);
        hf = CreateFileA(pwcsName,GENERIC_READ|GENERIC_WRITE,0,NULL,CREATE_NEW,0,0);
        if (hf==INVALID_HANDLE_VALUE) {
                WARN("couldn't open file for storage:%d\n",GetLastError());
                return E_FAIL;
        }
        lpstg = MapSL((SEGPTR)*ppstgOpen);
        lpstg->str.hf = hf;
        lpstg->str.lockbytes = 0;
        /* FIXME: check for existence before overwriting? */
        if (!STORAGE_init_storage(&lpstg->str)) {
                CloseHandle(hf);
                return E_FAIL;
        }
        i=0;ret=0;
        while (!ret) { /* neither 1 nor <0 */
                ret=STORAGE_get_pps_entry(&lpstg->str,i,&stde);
                if ((ret==1) && (stde.pps_type==5)) {
                        lpstg->stde     = stde;
                        lpstg->ppsent   = i;
                        break;
                }
                i++;
        }
        if (ret!=1) {
                IStorage16_fnRelease((IStorage16*)lpstg); /* will remove it */
                return E_FAIL;
        }

        return S_OK;
}

/******************************************************************************
 * StgIsStorageFile [STORAGE.5]
 */
HRESULT WINAPI StgIsStorageFile16(LPCOLESTR16 fn) {
        UNICODE_STRING strW;
        HRESULT ret;

        RtlCreateUnicodeStringFromAsciiz(&strW, fn);
        ret = StgIsStorageFile( strW.Buffer );
        RtlFreeUnicodeString( &strW );

        return ret;
}

/******************************************************************************
 * StgOpenStorage [STORAGE.3]
 */
HRESULT WINAPI StgOpenStorage16(
        LPCOLESTR16 pwcsName,IStorage16 *pstgPriority,DWORD grfMode,
        SNB16 snbExclude,DWORD reserved, IStorage16 **ppstgOpen
) {
        HANDLE          hf;
        int             ret,i;
        IStorage16Impl* lpstg;
        struct storage_pps_entry        stde;

        TRACE("(%s,%p,0x%08x,%p,%d,%p)\n",
              pwcsName,pstgPriority,grfMode,snbExclude,reserved,ppstgOpen
        );
        _create_istorage16(ppstgOpen);
        hf = CreateFileA(pwcsName,GENERIC_READ,FILE_SHARE_READ,NULL,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL,0);
        if (hf==INVALID_HANDLE_VALUE) {
                WARN("Couldn't open file for storage\n");
                return E_FAIL;
        }
        lpstg = MapSL((SEGPTR)*ppstgOpen);
        lpstg->str.hf = hf;

        i=0;ret=0;
        while (!ret) { /* neither 1 nor <0 */
                ret=STORAGE_get_pps_entry(&lpstg->str,i,&stde);
                if ((ret==1) && (stde.pps_type==5)) {
                        lpstg->stde=stde;
                        break;
                }
                i++;
        }
        if (ret!=1) {
                IStorage16_fnRelease((IStorage16*)lpstg); /* will remove it */
                return E_FAIL;
        }
        return S_OK;

}

/******************************************************************************
 *              StgIsStorageILockBytes        [STORAGE.6]
 *
 * Determines if the ILockBytes contains a storage object.
 */
HRESULT WINAPI StgIsStorageILockBytes16(SEGPTR plkbyt)
{
  DWORD args[6];
  HRESULT hres;
  HANDLE16 hsig;

  args[0] = (DWORD)plkbyt;      /* iface */
  args[1] = args[2] = 0;        /* ULARGE_INTEGER offset */
  args[3] = WOWGlobalAllocLock16( 0, 8, &hsig ); /* sig */
  args[4] = 8;
  args[5] = 0;

  if (!WOWCallback16Ex(
      (DWORD)((const ILockBytes16Vtbl*)MapSL(
                  (SEGPTR)((LPLOCKBYTES16)MapSL(plkbyt))->lpVtbl)
      )->ReadAt,
      WCB16_PASCAL,
      6*sizeof(DWORD),
      (LPVOID)args,
      (LPDWORD)&hres
  )) {
      ERR("CallTo16 ILockBytes16::ReadAt() failed, hres %x\n",hres);
      return hres;
  }
  if (memcmp(MapSL(args[3]), STORAGE_magic, sizeof(STORAGE_magic)) == 0) {
    WOWGlobalUnlockFree16(args[3]);
    return S_OK;
  }
  WOWGlobalUnlockFree16(args[3]);
  return S_FALSE;
}

/******************************************************************************
 *    StgOpenStorageOnILockBytes    [STORAGE.4]
 *
 * PARAMS
 *  plkbyt  FIXME: Should probably be an ILockBytes16 *.
 */
HRESULT WINAPI StgOpenStorageOnILockBytes16(
        SEGPTR plkbyt,
        IStorage16 *pstgPriority,
        DWORD grfMode,
        SNB16 snbExclude,
        DWORD reserved,
        IStorage16 **ppstgOpen)
{
        IStorage16Impl* lpstg;
        int i,ret;
        struct storage_pps_entry        stde;

        FIXME("(%x, %p, 0x%08x, %d, %x, %p)\n", plkbyt, pstgPriority, grfMode, (int)snbExclude, reserved, ppstgOpen);
        if ((plkbyt == 0) || (ppstgOpen == 0))
                return STG_E_INVALIDPOINTER;

        *ppstgOpen = 0;

        _create_istorage16(ppstgOpen);
        lpstg = MapSL((SEGPTR)*ppstgOpen);
        lpstg->str.hf = NULL;
        lpstg->str.lockbytes = plkbyt;
        i=0;ret=0;
        while (!ret) { /* neither 1 nor <0 */
                ret=STORAGE_get_pps_entry(&lpstg->str,i,&stde);
                if ((ret==1) && (stde.pps_type==5)) {
                        lpstg->stde=stde;
                        break;
                }
                i++;
        }
        if (ret!=1) {
                IStorage16_fnRelease((IStorage16*)lpstg); /* will remove it */
                return E_FAIL;
        }
        return S_OK;
}