vfdzip.c

Go to the documentation of this file.

/*
    vfdzip.c
 
    Virtual Floppy Drive for Windows
    Driver control library
    Zip compressed floppy image handling
 
    Copyright (C) 2003-2005 Ken Kato
*/
 
#ifdef __cplusplus
#pragma message(__FILE__": Compiled as C++ for testing purpose.")
#endif  // __cplusplus
 
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
 
#include "vfdtypes.h"
#include "vfdio.h"
#include "vfdlib.h"
 
#ifndef __REACTOS__
#define ZLIB_WINAPI
#else
#define Z_SOLO
#define ZLIB_INTERNAL
#endif
#include "zlib.h"
 
#ifdef VFD_NO_ZLIB
#pragma message("ZIP image support is disabled.")
 
DWORD ExtractZipInfo(
    HANDLE          hFile,
    ULONG           *pSize)
{
    UNREFERENCED_PARAMETER(hFile);
    UNREFERENCED_PARAMETER(pSize);
    return ERROR_NOT_SUPPORTED;
}
 
DWORD ExtractZipImage(
    HANDLE          hFile,
    PUCHAR          *pBuffer,
    PULONG          pLength)
{
    UNREFERENCED_PARAMETER(hFile);
    UNREFERENCED_PARAMETER(pBuffer);
    UNREFERENCED_PARAMETER(pLength);
    return ERROR_NOT_SUPPORTED;
}
 
#else   // VFD_NO_ZLIB
 
#ifdef _DEBUG
static const char *ZLIB_ERROR(int err)
{
    switch (err) {
    case Z_OK           : return "Z_OK";
    case Z_STREAM_END   : return "Z_STREAM_END";
    case Z_NEED_DICT    : return "Z_NEED_DICT";
    case Z_ERRNO        : return "Z_ERRNO";
    case Z_STREAM_ERROR : return "Z_STREAM_ERROR";
    case Z_DATA_ERROR   : return "Z_DATA_ERROR";
    case Z_MEM_ERROR    : return "Z_MEM_ERROR";
    case Z_BUF_ERROR    : return "Z_BUF_ERROR";
    case Z_VERSION_ERROR: return "Z_VERSION_ERROR";
    default             : return "unknown";
    }
}
#endif  // _DEBUG
 
voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size))
{
    UNREFERENCED_PARAMETER(opaque);
    return LocalAlloc(LPTR, items * size);
}
 
void   zcfree  OF((voidpf opaque, voidpf ptr))
{
    UNREFERENCED_PARAMETER(opaque);
    LocalFree(ptr);
}
 
#define ZIP_LOCAL_SIGNATURE         0x04034b50
 
#define ZIP_FLAG_ENCRYPTED          0x01
 
#define ZIP_FLAG_DEFLATE_NORMAL     0x00
#define ZIP_FLAG_DEFLATE_MAX        0x02
#define ZIP_FLAG_DEFLATE_FAST       0x04
#define ZIP_FLAG_DEFLATE_SUPER      0x06
#define ZIP_FLAG_DEFLATE_MASK       0x06
 
#define ZIP_FLAG_SIZE_IN_DESC       0x08
 
#define ZIP_METHOD_STORED           0
#define ZIP_METHOD_SHRUNK           1
#define ZIP_METHOD_REDUCED1         2
#define ZIP_METHOD_REDUCED2         3
#define ZIP_METHOD_REDUCED3         4
#define ZIP_METHOD_REDUCED4         5
#define ZIP_METHOD_IMPLODED         6
#define ZIP_METHOD_TOKENIZED        7
#define ZIP_METHOD_DEFLATED         8
#define ZIP_METHOD_DEFLATE64        9
#define ZIP_METHOD_PKWARE_IMP       10
#define ZIP_METHOD_RESERVED         11
#define ZIP_METHOD_BZIP2            12
 
#pragma pack(1)
 
typedef struct _zip_local_file_header {
    ULONG   header_signature;
    USHORT  required_version;
    USHORT  general_flags;
    USHORT  compression_method;
    USHORT  last_mod_time;
    USHORT  last_mod_date;
    ULONG   crc32;
    ULONG   compressed_size;
    ULONG   uncompressed_size;
    USHORT  file_name_length;
    USHORT  extra_field_length;
    CHAR    file_name[1];
    // followed by extra field data, then compressed data
}
ZIP_HEADER, *PZIP_HEADER;
 
//
//  Check if the file is ZIP compressed
//
DWORD ExtractZipInfo(
    HANDLE          hFile,
    ULONG           *pSize)
{
    ZIP_HEADER      zip_hdr;
    DWORD           result;
    DWORD           ret;
 
    if (SetFilePointer(hFile, 0, NULL, FILE_BEGIN) != 0) {
        ret = GetLastError();
 
        VFDTRACE(0,
            ("SetFilePointer() - %s\n",
            SystemMessage(ret)));
 
        return ret;
    }
 
    if (!ReadFile(hFile, &zip_hdr, sizeof(zip_hdr), &result, NULL)) {
        ret = GetLastError();
 
        VFDTRACE(0,
            ("ReadFile() - %s\n",
            SystemMessage(ret)));
 
        return ret;
    }
 
    if (result != sizeof(zip_hdr)                           ||
        zip_hdr.header_signature != ZIP_LOCAL_SIGNATURE     ||
        zip_hdr.compression_method != ZIP_METHOD_DEFLATED   ||
        (zip_hdr.general_flags & ZIP_FLAG_ENCRYPTED)) {
 
        VFDTRACE(0,
            ("[VFD] Invalid ZIP file\n"));
 
        return ERROR_INVALID_DATA;
    }
 
    //  correct (and supported) ZIP header detected
 
    *pSize = zip_hdr.uncompressed_size;
 
    return ERROR_SUCCESS;
}
 
//
//  Extract original data from IMZ file
//
DWORD ExtractZipImage(
    HANDLE          hFile,
    PUCHAR          *pBuffer,
    PULONG          pLength)
{
    UCHAR           buf[VFD_BYTES_PER_SECTOR];
    DWORD           result;
    DWORD           ret;
 
    PZIP_HEADER     zip_hdr;
    ULONG           compressed;
    ULONG           uncompressed;
    PUCHAR          file_cache;
    z_stream        stream;
    int             zlib_ret;
 
    VFDTRACE(0,
        ("[VFD] VfdExtractImz - IN\n"));
 
    *pBuffer = NULL;
    *pLength = 0;
 
    //
    //  Read PKZIP local file header of the first file in the file
    //  -- An IMZ file actually is just a ZIP file with a different
    //  extension, which contains a single floppy image file
    //
    if (SetFilePointer(hFile, 0, NULL, FILE_BEGIN) != 0) {
        ret = GetLastError();
 
        VFDTRACE(0,(
            "SetFilePointer - %s", SystemMessage(ret)));;
 
        return ret;
    }
 
    if (!ReadFile(hFile, buf, VFD_BYTES_PER_SECTOR, &result, NULL) ||
        result < VFD_BYTES_PER_SECTOR) {
 
        ret = GetLastError();
 
        VFDTRACE(0,(
            "ReadFile - %s", SystemMessage(ret)));;
 
        return ret;
    }
 
    zip_hdr = (PZIP_HEADER)buf;
 
    //  check local file header signature
 
    if (zip_hdr->header_signature != ZIP_LOCAL_SIGNATURE) {
 
        VFDTRACE(0,
            ("[VFD] PKZIP header signature not found.\n"));
 
        return ERROR_INVALID_DATA;
    }
 
    //  check compression method
 
    if (zip_hdr->compression_method != Z_DEFLATED) {
 
        VFDTRACE(0,
            ("[VFD] Bad PKZIP compression method.\n"));
 
        return ERROR_NOT_SUPPORTED;
    }
 
    if (zip_hdr->general_flags & 0x01) {
        //  encrypted zip not supported
 
        VFDTRACE(0,
            ("[VFD] PKZIP encrypted.\n"));
 
        return ERROR_NOT_SUPPORTED;
    }
 
    //  check uncompressed image size
 
    compressed = zip_hdr->compressed_size;
    uncompressed = zip_hdr->uncompressed_size;
 
    switch (uncompressed) {
    case VFD_SECTOR_TO_BYTE(320):
    case VFD_SECTOR_TO_BYTE(360):
    case VFD_SECTOR_TO_BYTE(640):
    case VFD_SECTOR_TO_BYTE(720):
    case VFD_SECTOR_TO_BYTE(1280):
    case VFD_SECTOR_TO_BYTE(1440):
    case VFD_SECTOR_TO_BYTE(1640):
    case VFD_SECTOR_TO_BYTE(2400):
    case VFD_SECTOR_TO_BYTE(2880):
    case VFD_SECTOR_TO_BYTE(3360):
    case VFD_SECTOR_TO_BYTE(3444):
    case VFD_SECTOR_TO_BYTE(5760):
        break;
 
    default:
        VFDTRACE(0,
            ("[VFD] Unsupported image size %lu.\n",
            uncompressed));
 
        return ERROR_NOT_SUPPORTED;
    }
 
    //  check local file header length
    //  -- Just for simplicity, the compressed data must start in the
    //  first sector in the file:  this is not a problem in most cases.
 
    if (FIELD_OFFSET(ZIP_HEADER, file_name) +
        zip_hdr->file_name_length +
        zip_hdr->extra_field_length >= VFD_BYTES_PER_SECTOR) {
 
        VFDTRACE(0,
            ("[VFD] PKZIP header too long.\n"));
 
        return ERROR_NOT_SUPPORTED;
    }
 
    //  allocate memory to store uncompressed data
 
    file_cache = (PUCHAR)LocalAlloc(LPTR, uncompressed);
 
    if (!file_cache) {
 
        VFDTRACE(0,
            ("[VFD] Failed to allocate file cache.\n"));
 
        return ERROR_OUTOFMEMORY;
    }
 
    //  initialize the zlib stream
 
    ZeroMemory(&stream, sizeof(stream));
 
    //  set initial input data information
 
    stream.next_in      = (PUCHAR)zip_hdr->file_name +
        zip_hdr->file_name_length + zip_hdr->extra_field_length;
 
    stream.avail_in     = VFD_BYTES_PER_SECTOR -
        FIELD_OFFSET(ZIP_HEADER, file_name) -
        zip_hdr->file_name_length - zip_hdr->extra_field_length;
 
    //  set output buffer information
 
    stream.next_out     = file_cache;
    stream.avail_out    = uncompressed;
 
    zlib_ret = inflateInit2(&stream, -MAX_WBITS);
 
    //  negative MAX_WBITS value passed to the inflateInit2() function
    //  indicates that there is no zlib header.
    //  In this case inflate() function requires an extra "dummy" byte
    //  after the compressed stream in order to complete decompression
    //  and return Z_STREAM_END.  However, both compressed and uncompressed
    //  data size are already known from the pkzip header, Z_STREAM_END
    //  is not absolutely necessary to know the completion of the operation.
 
    if (zlib_ret != Z_OK) {
        LocalFree(file_cache);
 
        VFDTRACE(0,
            ("[VFD] inflateInit2() failed - %s.\n",
            ZLIB_ERROR(zlib_ret)));
 
        return ERROR_INVALID_FUNCTION;
    }
 
    for (;;) {
 
        //  uncompress current block
 
        zlib_ret = inflate(&stream, Z_NO_FLUSH);
 
        if (zlib_ret != Z_OK) {
            if (zlib_ret == Z_STREAM_END) {
                ret = ERROR_SUCCESS;
            }
            else {
                VFDTRACE(0,
                    ("[VFD] inflate() failed - %s.\n",
                    ZLIB_ERROR(zlib_ret)));
 
                ret = ERROR_INVALID_FUNCTION;
            }
            break;
        }
 
        if (stream.total_out >= uncompressed) {
            //  uncompress completed - no need to wait for Z_STREAM_END
            //  (inflate() would return Z_STREAM_END on the next call)
            ret = ERROR_SUCCESS;
            break;
        }
 
        if (stream.total_in >= compressed) {
            //  somehow there is not enought compressed data
            ret = ERROR_INVALID_FUNCTION;
            break;
        }
 
        //  read next block from file
 
        if (!ReadFile(hFile, buf, VFD_BYTES_PER_SECTOR, &result, NULL) ||
            result <= 0) {
 
            ret = GetLastError();
 
            VFDTRACE(0,
                ("[VFD] Read compressed data - %s.\n",
                SystemMessage(ret)));
            break;
        }
 
        stream.avail_in = result;
        stream.next_in  = buf;
    }
 
    //  cleanup the zlib stream
 
    inflateEnd(&stream);
 
    //  set the return information
 
    if (ret == ERROR_SUCCESS) {
        *pBuffer    = file_cache;
        *pLength    = uncompressed;
    }
    else {
        LocalFree(file_cache);
    }
 
    VFDTRACE(0,
        ("[VFD] VfdExtractImz - OUT\n"));
 
    return ret;
}
 
#endif  //  VFD_NO_ZLIB