/*

 * Extended attribute functions

 *

 * Copyright (C) 2018-2025, 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 <memory.h>

#include <types.h>

#include "libfsapfs_attributes.h"

#include "libfsapfs_data_stream.h"

#include "libfsapfs_debug.h"

#include "libfsapfs_encryption_context.h"

#include "libfsapfs_extended_attribute.h"

#include "libfsapfs_file_extent.h"

#include "libfsapfs_file_system_btree.h"

#include "libfsapfs_io_handle.h"

#include "libfsapfs_libbfio.h"

#include "libfsapfs_libcerror.h"

#include "libfsapfs_libcnotify.h"

#include "libfsapfs_libcthreads.h"

#include "libfsapfs_libfdata.h"

#include "libfsapfs_libfdatetime.h"

#include "libfsapfs_types.h"

/* Creates an extended_attribute

 * Make sure the value extended_attribute is referencing, is set to NULL

 * Returns 1 if successful or -1 on error

 */

int libfsapfs_extended_attribute_initialize(

     libfsapfs_extended_attribute_t **extended_attribute,

     libfsapfs_io_handle_t *io_handle,

     libbfio_handle_t *file_io_handle,

     libfsapfs_encryption_context_t *encryption_context,

     libfsapfs_file_system_btree_t *file_system_btree,

     libfsapfs_attribute_values_t *attribute_values,

     uint64_t transaction_identifier,

     libcerror_error_t **error )

{

  libfsapfs_internal_extended_attribute_t *internal_extended_attribute = NULL;

  static char *function                                                = "libfsapfs_extended_attribute_initialize";

  if( extended_attribute == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid extended attribute.",

     function );

    return( -1 );

  }

  if( *extended_attribute != NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_VALUE_ALREADY_SET,

     "%s: invalid extended attribute value already set.",

     function );

    return( -1 );

  }

  if( attribute_values == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid attribute values.",

     function );

    return( -1 );

  }

  internal_extended_attribute = memory_allocate_structure(

                                 libfsapfs_internal_extended_attribute_t );

  if( internal_extended_attribute == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_MEMORY,

     LIBCERROR_MEMORY_ERROR_INSUFFICIENT,

     "%s: unable to create extended attribute.",

     function );

    goto on_error;

  }

  if( memory_set(

       internal_extended_attribute,

       0,

       sizeof( libfsapfs_internal_extended_attribute_t ) ) == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_MEMORY,

     LIBCERROR_MEMORY_ERROR_SET_FAILED,

     "%s: unable to clear extended attribute.",

     function );

    memory_free(

     internal_extended_attribute );

    return( -1 );

  }

  internal_extended_attribute->io_handle              = io_handle;

  internal_extended_attribute->file_io_handle         = file_io_handle;

  internal_extended_attribute->encryption_context     = encryption_context;

  internal_extended_attribute->file_system_btree      = file_system_btree;

  internal_extended_attribute->attribute_values       = attribute_values;

  internal_extended_attribute->transaction_identifier = transaction_identifier;

#if defined( HAVE_MULTI_THREAD_SUPPORT ) && !defined( HAVE_LOCAL_LIBFSAPFS )

  if( libcthreads_read_write_lock_initialize(

       &( internal_extended_attribute->read_write_lock ),

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_INITIALIZE_FAILED,

     "%s: unable to initialize read/write lock.",

     function );

    goto on_error;

  }

#endif

  *extended_attribute = (libfsapfs_extended_attribute_t *) internal_extended_attribute;

  return( 1 );

on_error:

  if( internal_extended_attribute != NULL )

  {

    memory_free(

     internal_extended_attribute );

  }

  return( -1 );

}

/* Frees an extended attribute

 * Returns 1 if successful or -1 on error

 */

int libfsapfs_extended_attribute_free(

     libfsapfs_extended_attribute_t **extended_attribute,

     libcerror_error_t **error )

{

  libfsapfs_internal_extended_attribute_t *internal_extended_attribute = NULL;

  static char *function                                                = "libfsapfs_extended_attribute_free";

  int result                                                           = 1;

  if( extended_attribute == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid extended attribute.",

     function );

    return( -1 );

  }

  if( *extended_attribute != NULL )

  {

    internal_extended_attribute = (libfsapfs_internal_extended_attribute_t *) *extended_attribute;

    *extended_attribute         = NULL;

#if defined( HAVE_MULTI_THREAD_SUPPORT ) && !defined( HAVE_LOCAL_LIBFSAPFS )

    if( libcthreads_read_write_lock_free(

         &( internal_extended_attribute->read_write_lock ),

         error ) != 1 )

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_RUNTIME,

       LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,

       "%s: unable to free read/write lock.",

       function );

      result = -1;

    }

#endif

    if( internal_extended_attribute->data_stream != NULL )

    {

      if( libfdata_stream_free(

           &( internal_extended_attribute->data_stream ),

           error ) != 1 )

      {

        libcerror_error_set(

         error,

         LIBCERROR_ERROR_DOMAIN_RUNTIME,

         LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,

         "%s: unable to free data stream.",

         function );

        result = -1;

      }

    }

    memory_free(

     internal_extended_attribute );

  }

  return( result );

}

/* Retrieves the data stream

 * Returns 1 if successful or -1 on error

 */

int libfsapfs_extended_attribute_get_data_stream(

     libfsapfs_extended_attribute_t *extended_attribute,

     libfdata_stream_t **data_stream,

     libcerror_error_t **error )

{

  libfsapfs_internal_extended_attribute_t *internal_extended_attribute = NULL;

  static char *function                                                = "libfsapfs_extended_attribute_get_data_stream";

  if( extended_attribute == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid extended attribute.",

     function );

    return( -1 );

  }

  internal_extended_attribute = (libfsapfs_internal_extended_attribute_t *) extended_attribute;

  if( data_stream == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid data stream.",

     function );

    return( -1 );

  }

  if( internal_extended_attribute->data_stream == NULL )

  {

    if( libfsapfs_internal_extended_attribute_get_data_stream(

         internal_extended_attribute,

         error ) != 1 )

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_RUNTIME,

       LIBCERROR_RUNTIME_ERROR_GET_FAILED,

       "%s: unable to determine data stream.",

       function );

      return( -1 );

    }

  }

  *data_stream = internal_extended_attribute->data_stream;

  return( 1 );

}

/* Retrieves the identifier

 * Returns 1 if successful or -1 on error

 */

int libfsapfs_extended_attribute_get_identifier(

     libfsapfs_extended_attribute_t *extended_attribute,

     uint64_t *identifier,

     libcerror_error_t **error )

{

  libfsapfs_internal_extended_attribute_t *internal_extended_attribute = NULL;

  static char *function                                                = "libfsapfs_extended_attribute_get_identifier";

  if( extended_attribute == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid extended attribute.",

     function );

    return( -1 );

  }

  internal_extended_attribute = (libfsapfs_internal_extended_attribute_t *) extended_attribute;

  if( identifier == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid identifier.",

     function );

    return( -1 );

  }

#if defined( HAVE_LIBFSAPFS_MULTI_THREAD_SUPPORT )

  if( libcthreads_read_write_lock_grab_for_read(

       internal_extended_attribute->read_write_lock,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_SET_FAILED,

     "%s: unable to grab read/write lock for reading.",

     function );

    return( -1 );

  }

#endif

  *identifier = internal_extended_attribute->identifier;

#if defined( HAVE_LIBFSAPFS_MULTI_THREAD_SUPPORT )

  if( libcthreads_read_write_lock_release_for_read(

       internal_extended_attribute->read_write_lock,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_SET_FAILED,

     "%s: unable to release read/write lock for reading.",

     function );

    return( -1 );

  }

#endif

  return( 1 );

}

/* Retrieves the size of the UTF-8 encoded name

 * The returned size includes the end of string character

 * Returns 1 if successful or -1 on error

 */

int libfsapfs_extended_attribute_get_utf8_name_size(

     libfsapfs_extended_attribute_t *extended_attribute,

     size_t *utf8_string_size,

     libcerror_error_t **error )

{

  libfsapfs_internal_extended_attribute_t *internal_extended_attribute = NULL;

  static char *function                                                = "libfsapfs_extended_attribute_get_utf8_name_size";

  int result                                                           = 1;

  if( extended_attribute == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid extended attribute.",

     function );

    return( -1 );

  }

  internal_extended_attribute = (libfsapfs_internal_extended_attribute_t *) extended_attribute;

#if defined( HAVE_LIBFSAPFS_MULTI_THREAD_SUPPORT )

  if( libcthreads_read_write_lock_grab_for_read(

       internal_extended_attribute->read_write_lock,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_SET_FAILED,

     "%s: unable to grab read/write lock for reading.",

     function );

    return( -1 );

  }

#endif

  if( libfsapfs_attribute_values_get_utf8_name_size(

       internal_extended_attribute->attribute_values,

       utf8_string_size,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_GET_FAILED,

     "%s: unable to retrieve UTF-8 string size.",

     function );

    result = -1;

  }

#if defined( HAVE_LIBFSAPFS_MULTI_THREAD_SUPPORT )

  if( libcthreads_read_write_lock_release_for_read(

       internal_extended_attribute->read_write_lock,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_SET_FAILED,

     "%s: unable to release read/write lock for reading.",

     function );

    return( -1 );

  }

#endif

  return( result );

}

/* Retrieves the UTF-8 encoded name

 * The size should include the end of string character

 * Returns 1 if successful or -1 on error

 */

int libfsapfs_extended_attribute_get_utf8_name(

     libfsapfs_extended_attribute_t *extended_attribute,

     uint8_t *utf8_string,

     size_t utf8_string_size,

     libcerror_error_t **error )

{

  libfsapfs_internal_extended_attribute_t *internal_extended_attribute = NULL;

  static char *function                                                = "libfsapfs_extended_attribute_get_utf8_name";

  int result                                                           = 1;

  if( extended_attribute == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid extended attribute.",

     function );

    return( -1 );

  }

  internal_extended_attribute = (libfsapfs_internal_extended_attribute_t *) extended_attribute;

#if defined( HAVE_LIBFSAPFS_MULTI_THREAD_SUPPORT )

  if( libcthreads_read_write_lock_grab_for_read(

       internal_extended_attribute->read_write_lock,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_SET_FAILED,

     "%s: unable to grab read/write lock for reading.",

     function );

    return( -1 );

  }

#endif

  if( libfsapfs_attribute_values_get_utf8_name(

       internal_extended_attribute->attribute_values,

       utf8_string,

       utf8_string_size,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_GET_FAILED,

     "%s: unable to retrieve UTF-8 string.",

     function );

    result = -1;

  }

#if defined( HAVE_LIBFSAPFS_MULTI_THREAD_SUPPORT )

  if( libcthreads_read_write_lock_release_for_read(

       internal_extended_attribute->read_write_lock,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_SET_FAILED,

     "%s: unable to release read/write lock for reading.",

     function );

    return( -1 );

  }

#endif

  return( result );

}

/* Retrieves the size of the UTF-16 encoded name

 * The returned size includes the end of string character

 * Returns 1 if successful or -1 on error

 */

int libfsapfs_extended_attribute_get_utf16_name_size(

     libfsapfs_extended_attribute_t *extended_attribute,

     size_t *utf16_string_size,

     libcerror_error_t **error )

{

  libfsapfs_internal_extended_attribute_t *internal_extended_attribute = NULL;

  static char *function                                                = "libfsapfs_extended_attribute_get_utf16_name_size";

  int result                                                           = 1;

  if( extended_attribute == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid extended attribute.",

     function );

    return( -1 );

  }

  internal_extended_attribute = (libfsapfs_internal_extended_attribute_t *) extended_attribute;

#if defined( HAVE_LIBFSAPFS_MULTI_THREAD_SUPPORT )

  if( libcthreads_read_write_lock_grab_for_read(

       internal_extended_attribute->read_write_lock,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_SET_FAILED,

     "%s: unable to grab read/write lock for reading.",

     function );

    return( -1 );

  }

#endif

  if( libfsapfs_attribute_values_get_utf16_name_size(

       internal_extended_attribute->attribute_values,

       utf16_string_size,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_GET_FAILED,

     "%s: unable to retrieve UTF-16 string size.",

     function );

    result = -1;

  }

#if defined( HAVE_LIBFSAPFS_MULTI_THREAD_SUPPORT )

  if( libcthreads_read_write_lock_release_for_read(

       internal_extended_attribute->read_write_lock,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_SET_FAILED,

     "%s: unable to release read/write lock for reading.",

     function );

    return( -1 );

  }

#endif

  return( result );

}

/* Retrieves the UTF-16 encoded name

 * The size should include the end of string character

 * Returns 1 if successful or -1 on error

 */

int libfsapfs_extended_attribute_get_utf16_name(

     libfsapfs_extended_attribute_t *extended_attribute,

     uint16_t *utf16_string,

     size_t utf16_string_size,

     libcerror_error_t **error )

{

  libfsapfs_internal_extended_attribute_t *internal_extended_attribute = NULL;

  static char *function                                                = "libfsapfs_extended_attribute_get_utf16_name";

  int result                                                           = 1;

  if( extended_attribute == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid extended attribute.",

     function );

    return( -1 );

  }

  internal_extended_attribute = (libfsapfs_internal_extended_attribute_t *) extended_attribute;

#if defined( HAVE_LIBFSAPFS_MULTI_THREAD_SUPPORT )

  if( libcthreads_read_write_lock_grab_for_read(

       internal_extended_attribute->read_write_lock,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_SET_FAILED,

     "%s: unable to grab read/write lock for reading.",

     function );

    return( -1 );

  }

#endif

  if( libfsapfs_attribute_values_get_utf16_name(

       internal_extended_attribute->attribute_values,

       utf16_string,

       utf16_string_size,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_GET_FAILED,

     "%s: unable to retrieve UTF-16 string.",

     function );

    result = -1;

  }

#if defined( HAVE_LIBFSAPFS_MULTI_THREAD_SUPPORT )

  if( libcthreads_read_write_lock_release_for_read(

       internal_extended_attribute->read_write_lock,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_SET_FAILED,

     "%s: unable to release read/write lock for reading.",

     function );

    return( -1 );

  }

#endif

  return( result );

}

/* Determines the data stream

 * Returns 1 if successful or -1 on error

 */

int libfsapfs_internal_extended_attribute_get_data_stream(

     libfsapfs_internal_extended_attribute_t *internal_extended_attribute,

     libcerror_error_t **error )

{

  static char *function = "libfsapfs_internal_extended_attribute_get_data_stream";

  if( internal_extended_attribute == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid extended attribute.",

     function );

    return( -1 );

  }

  if( internal_extended_attribute->data_stream != NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_VALUE_ALREADY_SET,

     "%s: invalid extended attribute - data stream value already set.",

     function );

    return( -1 );

  }

  if( libfsapfs_attributes_get_data_stream(

       internal_extended_attribute->attribute_values,

       internal_extended_attribute->io_handle,

       internal_extended_attribute->file_io_handle,

       internal_extended_attribute->encryption_context,

       internal_extended_attribute->file_system_btree,

       internal_extended_attribute->transaction_identifier,

       &( internal_extended_attribute->data_stream ),

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_GET_FAILED,

     "%s: unable to retrieve attribute value data stream.",

     function );

    return( -1 );

  }

  return( 1 );

}

/* Reads data at the current offset into a buffer

 * Returns the number of bytes read or -1 on error

 */

ssize_t libfsapfs_extended_attribute_read_buffer(

         libfsapfs_extended_attribute_t *extended_attribute,

         void *buffer,

         size_t buffer_size,

         libcerror_error_t **error )

{

  libfsapfs_internal_extended_attribute_t *internal_extended_attribute = NULL;

  static char *function                                                = "libfsapfs_extended_attribute_read_buffer";

  ssize_t read_count                                                   = 0;

  if( extended_attribute == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid extended attribute.",

     function );

    return( -1 );

  }

  internal_extended_attribute = (libfsapfs_internal_extended_attribute_t *) extended_attribute;

#if defined( HAVE_LIBFSAPFS_MULTI_THREAD_SUPPORT )

  if( libcthreads_read_write_lock_grab_for_write(

       internal_extended_attribute->read_write_lock,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_SET_FAILED,

     "%s: unable to grab read/write lock for writing.",

     function );

    return( -1 );

  }

#endif

  if( internal_extended_attribute->data_stream == NULL )

  {

    if( libfsapfs_internal_extended_attribute_get_data_stream(

         internal_extended_attribute,

         error ) != 1 )

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_RUNTIME,

       LIBCERROR_RUNTIME_ERROR_GET_FAILED,

       "%s: unable to determine data stream.",

       function );

      read_count = -1;

    }

  }

  if( internal_extended_attribute->data_stream != NULL )

  {

    read_count = libfdata_stream_read_buffer(

                  internal_extended_attribute->data_stream,

                  (intptr_t *) internal_extended_attribute->file_io_handle,

                  (uint8_t *) buffer,

                  buffer_size,

                  0,

                  error );

    if( read_count < 0 )

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_IO,

       LIBCERROR_IO_ERROR_READ_FAILED,

       "%s: unable to read buffer from data stream.",

       function );

      read_count = -1;

    }

  }

#if defined( HAVE_LIBFSAPFS_MULTI_THREAD_SUPPORT )

  if( libcthreads_read_write_lock_release_for_write(

       internal_extended_attribute->read_write_lock,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_SET_FAILED,

     "%s: unable to release read/write lock for writing.",

     function );

    return( -1 );

  }

#endif

  return( read_count );

}

/* Reads data at a specific offset

 * Returns the number of bytes read or -1 on error

 */

ssize_t libfsapfs_extended_attribute_read_buffer_at_offset(

         libfsapfs_extended_attribute_t *extended_attribute,

         void *buffer,

         size_t buffer_size,

         off64_t offset,

         libcerror_error_t **error )

{

  libfsapfs_internal_extended_attribute_t *internal_extended_attribute = NULL;

  static char *function                                                = "libfsapfs_extended_attribute_read_buffer_at_offset";

  ssize_t read_count                                                   = 0;

  if( extended_attribute == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid extended attribute.",

     function );

    return( -1 );

  }

  internal_extended_attribute = (libfsapfs_internal_extended_attribute_t *) extended_attribute;

#if defined( HAVE_LIBFSAPFS_MULTI_THREAD_SUPPORT )

  if( libcthreads_read_write_lock_grab_for_write(

       internal_extended_attribute->read_write_lock,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_SET_FAILED,

     "%s: unable to grab read/write lock for writing.",

     function );

    return( -1 );

  }

#endif

  if( internal_extended_attribute->data_stream == NULL )

  {

    if( libfsapfs_internal_extended_attribute_get_data_stream(

         internal_extended_attribute,

         error ) != 1 )

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_RUNTIME,

       LIBCERROR_RUNTIME_ERROR_GET_FAILED,

       "%s: unable to determine data stream.",

       function );

      read_count = -1;

    }

  }

  if( internal_extended_attribute->data_stream != NULL )

  {

    read_count = libfdata_stream_read_buffer_at_offset(

                  internal_extended_attribute->data_stream,

                  (intptr_t *) internal_extended_attribute->file_io_handle,

                  (uint8_t *) buffer,

                  buffer_size,

                  offset,

                  0,

                  error );

    if( read_count < 0 )

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_IO,

       LIBCERROR_IO_ERROR_READ_FAILED,

       "%s: unable to read buffer at offset from data stream.",

       function );

      read_count = -1;

    }

  }

#if defined( HAVE_LIBFSAPFS_MULTI_THREAD_SUPPORT )

  if( libcthreads_read_write_lock_release_for_write(

       internal_extended_attribute->read_write_lock,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_SET_FAILED,

     "%s: unable to release read/write lock for writing.",

     function );

    return( -1 );

  }

#endif

  return( read_count );

}

/* Seeks a certain offset

 * Returns the offset if seek is successful or -1 on error

 */

off64_t libfsapfs_extended_attribute_seek_offset(

         libfsapfs_extended_attribute_t *extended_attribute,

         off64_t offset,

         int whence,

         libcerror_error_t **error )

{

  libfsapfs_internal_extended_attribute_t *internal_extended_attribute = NULL;

  static char *function                                                = "libfsapfs_extended_attribute_seek_offset";

  if( extended_attribute == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid extended attribute.",