/* Builds the index from the files
*/
LIBEWF_HANDLE *libewf_build_index( LIBEWF_HANDLE *handle )
{
EWF_SECTION *last_section = NULL;
uint32_t segment = 0;
if( handle == NULL )
{
LIBEWF_FATAL_PRINT( "libewf_build_index: incorrect handle\n" );
}
if( handle->index_build != 0 )
{
LIBEWF_FATAL_PRINT( "libewf_build_index: index has already been build\n" );
}
for( segment = 1; segment < handle->segment_table->amount; segment++ )
{
LIBEWF_VERBOSE_PRINT( "libewf_build_index: building index for segment: %" PRIu32 "\n", segment );
last_section = libewf_sections_read_segment( handle, segment );
}
/* Check to see if we are done */
if( ( last_section == NULL ) || ( !ewf_section_is_type_done( last_section ) ) )
{
LIBEWF_FATAL_PRINT( "libewf_build_index: no ending section, cannot find the last segment file\n" );
}
ewf_section_free( last_section );
handle->index_build = 1;
LIBEWF_VERBOSE_PRINT( "libewf_build_index: index successful build.\n" );
return( handle );
}
/* Reads and processes sections of a segment file
* Returns the last section read, or NULL on error
*/
EWF_SECTION *libewf_read_sections_from_segment( LIBEWF_INTERNAL_HANDLE *internal_handle, uint16_t segment_number )
{
EWF_SECTION *section = NULL;
int file_descriptor = 0;
/* The first offset is directly after the file header (13 byte)
*/
off_t previous_offset = (off_t) EWF_FILE_HEADER_SIZE;
if( internal_handle == NULL )
{
LIBEWF_WARNING_PRINT( "libewf_sections_read_segment: invalid handle.\n" );
return( NULL );
}
if( libewf_segment_table_values_is_set( internal_handle->segment_table, segment_number ) == 0 )
{
LIBEWF_WARNING_PRINT( "libewf_sections_read_segment: missing a segment file for segment %" PRIu32 ".\n", segment_number );
return( NULL );
}
file_descriptor = libewf_segment_table_get_file_descriptor( internal_handle->segment_table, segment_number );
if( file_descriptor <= -1 )
{
LIBEWF_WARNING_PRINT( "libewf_sections_read_segment: invalid file descriptor.\n" );
return( NULL );
}
do
{
if( section != NULL )
{
libewf_common_free( section );
}
section = libewf_section_read( internal_handle, file_descriptor, internal_handle->segment_table->section_list[ segment_number ], segment_number, &previous_offset );
if( section == NULL )
{
LIBEWF_WARNING_PRINT( "libewf_sections_read_segment: unable to read section.\n" );
return( NULL );
}
/* The done and next sections point back at themselves
*/
if( ( ewf_section_is_type_next( section ) == 1 ) || ( ewf_section_is_type_done( section ) == 1 ) )
{
break;
}
}
while( section != NULL );
return( section );
}
/* Builds the index (section list and offset table) from the input files
* Returns 1 if successful, or -1 on error
*/
int8_t libewf_read_build_index( LIBEWF_INTERNAL_HANDLE *internal_handle )
{
EWF_SECTION *last_section = NULL;
uint16_t segment_number = 0;
if( internal_handle == NULL )
{
LIBEWF_WARNING_PRINT( "libewf_read_build_index: invalid handle.\n" );
return( -1 );
}
if( internal_handle->index_build != 0 )
{
LIBEWF_WARNING_PRINT( "libewf_read_build_index: index has already been build.\n" );
return( -1 );
}
if( libewf_internal_handle_read_initialize( internal_handle ) != 1 )
{
LIBEWF_WARNING_PRINT( "libewf_read_build_index: unable to initialize read values in handle.\n" );
return( -1 );
}
for( segment_number = 1; segment_number < internal_handle->segment_table->amount; segment_number++ )
{
if( last_section != NULL )
{
libewf_common_free( last_section );
}
LIBEWF_VERBOSE_PRINT( "libewf_read_build_index: building index for segment number: %" PRIu32 ".\n", segment_number );
last_section = libewf_read_sections_from_segment( internal_handle, segment_number );
}
/* Check to see if the done section has been found
*/
if( last_section == NULL )
{
LIBEWF_WARNING_PRINT( "libewf_read_build_index: invalid last section.\n" );
return( -1 );
}
else if( ewf_section_is_type_done( last_section ) == 0 )
{
LIBEWF_WARNING_PRINT( "libewf_read_build_index: unable to find the last segment file (done section).\n" );
libewf_common_free( last_section );
return( -1 );
}
libewf_common_free( last_section );
/* Determine the EWF file format
*/
if( libewf_internal_handle_determine_format( internal_handle ) != 1 )
{
LIBEWF_WARNING_PRINT( "libewf_read_build_index: unable to determine file format.\n" );
}
LIBEWF_VERBOSE_PRINT( "libewf_read_build_index: index successful build.\n" );
/* Calculate the media size
*/
internal_handle->media->media_size = (uint64_t) internal_handle->media->amount_of_sectors * (uint64_t) internal_handle->media->bytes_per_sector;
/* Flag that the index was build
*/
internal_handle->index_build = 1;
return( 1 );
}
