/*

 * Compression functions

 *

 * Copyright (c) 2010, Joachim Metz <joachim.metz@gmail.com>

 *

 * Refer to AUTHORS for acknowledgements.

 *

 * This program 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 3 of the License, or

 * (at your option) any later version.

 *

 * This program 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 General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License

 * along with this program.  If not, see <https://www.gnu.org/licenses/>.

 */

#include <common.h>

#include <byte_stream.h>

#include <file_stream.h>

#include <memory.h>

#include <types.h>

#if defined( HAVE_STDLIB_H ) || defined( WINAPI )

#include <stdlib.h>

#endif

#if defined( HAVE_ZLIB ) || defined( ZLIB_DLL )

#include <zlib.h>

#endif

#include "libqcow_compression.h"

#include "libqcow_definitions.h"

#include "libqcow_deflate.h"

#include "libqcow_libcerror.h"

#include "libqcow_libcnotify.h"

/* Decompresses data using the compression method

 * Returns 1 on success, 0 on failure or -1 on error

 */

int libqcow_decompress_data(

     const uint8_t *compressed_data,

     size_t compressed_data_size,

     uint16_t compression_method,

     uint8_t *uncompressed_data,

     size_t *uncompressed_data_size,

     libcerror_error_t **error )

{

  static char *function = "libqcow_decompress_data";

  int result            = 0;

#if ( defined( HAVE_ZLIB ) && defined( HAVE_ZLIB_INFLATE ) ) || defined( ZLIB_DLL )

  z_stream zlib_stream;

#endif

  if( compressed_data == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid compressed data buffer.",

     function );

    return( -1 );

  }

  if( uncompressed_data == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid uncompressed data buffer.",

     function );

    return( -1 );

  }

  if( uncompressed_data == compressed_data )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid compressed data buffer equals uncompressed data buffer.",

     function );

    return( -1 );

  }

  if( uncompressed_data_size == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid uncompressed data size.",

     function );

    return( -1 );

  }

  if( compression_method == LIBQCOW_COMPRESSION_METHOD_DEFLATE )

  {

#if ( defined( HAVE_ZLIB ) && defined( HAVE_ZLIB_INFLATE ) ) || defined( ZLIB_DLL )

    if( compressed_data_size > (size_t) ULONG_MAX )

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

       LIBCERROR_ARGUMENT_ERROR_VALUE_EXCEEDS_MAXIMUM,

       "%s: invalid compressed data size value exceeds maximum.",

       function );

      return( -1 );

    }

    if( *uncompressed_data_size > (size_t) ULONG_MAX )

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

       LIBCERROR_ARGUMENT_ERROR_VALUE_EXCEEDS_MAXIMUM,

       "%s: invalid uncompressed data size value exceeds maximum.",

       function );

      return( -1 );

    }

    if( memory_set(

         &zlib_stream,

         0,

         sizeof( z_stream ) ) == NULL )

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_MEMORY,

       LIBCERROR_MEMORY_ERROR_SET_FAILED,

       "%s: unable to clear zlib stream.",

       function );

      return( -1 );

    }

    zlib_stream.next_in   = (Bytef *) compressed_data;

    zlib_stream.avail_in  = (uInt) compressed_data_size;

    zlib_stream.next_out  = (Bytef *) uncompressed_data;

    zlib_stream.avail_out = (uInt) *uncompressed_data_size;

#if defined( HAVE_ZLIB_INFLATE_INIT2 ) || defined( ZLIB_DLL )

    result = inflateInit2(

              &zlib_stream,

              -12 );

#else

    result = _inflateInit2(

              &zlib_stream,

              -12 );

#endif

    if( result != Z_OK )

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_RUNTIME,

       LIBCERROR_RUNTIME_ERROR_INITIALIZE_FAILED,

       "%s: unable to initialize zlib stream.",

       function );

      return( -1 );

    }

    result = inflate(

              &zlib_stream,

              Z_FINISH );

    if( result == Z_STREAM_END )

    {

      *uncompressed_data_size = (size_t) zlib_stream.total_out;

      result = 1;

    }

    else if( result == Z_DATA_ERROR )

    {

#if defined( HAVE_DEBUG_OUTPUT )

      if( libcnotify_verbose != 0 )

      {

        libcnotify_printf(

         "%s: unable to read compressed data: data error.\n",

         function );

      }

#endif

      *uncompressed_data_size = 0;

      result = -1;

    }

    else if( result == Z_BUF_ERROR )

    {

#if defined( HAVE_DEBUG_OUTPUT )

      if( libcnotify_verbose != 0 )

      {

        libcnotify_printf(

        "%s: unable to read compressed data: target buffer too small.\n",

         function );

      }

#endif

      /* Estimate that a factor 2 enlargement should suffice

       */

      *uncompressed_data_size *= 2;

      result = 0;

    }

    else if( result == Z_MEM_ERROR )

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_MEMORY,

       LIBCERROR_MEMORY_ERROR_INSUFFICIENT,

       "%s: unable to read compressed data: insufficient memory.",

       function );

      *uncompressed_data_size = 0;

      result = -1;

    }

    else

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_COMPRESSION,

       LIBCERROR_COMPRESSION_ERROR_DECOMPRESS_FAILED,

       "%s: zlib returned undefined error: %d.",

       function,

       result );

      *uncompressed_data_size = 0;

      result = -1;

    }

    if( result == -1 )

    {

      inflateEnd(

       &zlib_stream );

    }

    else

    {

      if( inflateEnd(

           &zlib_stream ) != Z_OK )

      {

        libcerror_error_set(

         error,

         LIBCERROR_ERROR_DOMAIN_RUNTIME,

         LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,

         "%s: unable to finalize zlib stream.",

         function );

        return( -1 );

      }

    }

#else

    result = libqcow_deflate_decompress(

              compressed_data,

              compressed_data_size,

              uncompressed_data,

              uncompressed_data_size,

              error );

    if( result != 1 )

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_ENCRYPTION,

       LIBCERROR_ENCRYPTION_ERROR_GENERIC,

       "%s: unable to decompress deflate compressed data.",

       function );

      return( -1 );

    }

#endif /* ( defined( HAVE_ZLIB ) && defined( HAVE_ZLIB_INFLATE ) ) || defined( ZLIB_DLL ) */

  }

  else

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_UNSUPPORTED_VALUE,

     "%s: unsupported compression method.",

     function );

    return( -1 );

  }

  return( result );

}