static FT_Error
cff_index_init( CFF_Index idx,
FT_Stream stream,
FT_Bool load )
{
FT_Error error;
FT_Memory memory = stream->memory;
FT_UShort count;
FT_MEM_ZERO( idx, sizeof ( *idx ) );
idx->stream = stream;
idx->start = FT_STREAM_POS();
if ( !FT_READ_USHORT( count ) &&
count > 0 )
{
FT_Byte offsize;
FT_ULong size;
/* there is at least one element; read the offset size, */
/* then access the offset table to compute the index's total size */
if ( FT_READ_BYTE( offsize ) )
goto Exit;
if ( offsize < 1 || offsize > 4 )
{
error = FT_Err_Invalid_Table;
goto Exit;
}
idx->count = count;
idx->off_size = offsize;
size = (FT_ULong)( count + 1 ) * offsize;
idx->data_offset = idx->start + 3 + size;
if ( FT_STREAM_SKIP( size - offsize ) )
goto Exit;
size = cff_index_read_offset( idx, &error );
if ( error )
goto Exit;
if ( size == 0 )
{
error = CFF_Err_Invalid_Table;
goto Exit;
}
idx->data_size = --size;
if ( load )
{
/* load the data */
if ( FT_FRAME_EXTRACT( size, idx->bytes ) )
goto Exit;
}
else
{
/* skip the data */
if ( FT_STREAM_SKIP( size ) )
goto Exit;
}
}
Exit:
if ( error )
FT_FREE( idx->offsets );
return error;
}
cff_index_access_element( CFF_Index idx,
FT_UInt element,
FT_Byte** pbytes,
FT_ULong* pbyte_len )
{
FT_Error error = CFF_Err_Ok;
if ( idx && idx->count > element )
{
/* compute start and end offsets */
FT_Stream stream = idx->stream;
FT_ULong off1, off2 = 0;
/* load offsets from file or the offset table */
if ( !idx->offsets )
{
FT_ULong pos = element * idx->off_size;
if ( FT_STREAM_SEEK( idx->start + 3 + pos ) )
goto Exit;
off1 = cff_index_read_offset( idx, &error );
if ( error )
goto Exit;
if ( off1 != 0 )
{
do
{
element++;
off2 = cff_index_read_offset( idx, &error );
}
while ( off2 == 0 && element < idx->count );
}
}
else /* use offsets table */
{
off1 = idx->offsets[element];
if ( off1 )
{
do
{
element++;
off2 = idx->offsets[element];
} while ( off2 == 0 && element < idx->count );
}
}
/* access element */
if ( off1 && off2 > off1 )
{
*pbyte_len = off2 - off1;
if ( idx->bytes )
{
/* this index was completely loaded in memory, that's easy */
*pbytes = idx->bytes + off1 - 1;
}
else
{
/* this index is still on disk/file, access it through a frame */
if ( FT_STREAM_SEEK( idx->data_offset + off1 - 1 ) ||
FT_FRAME_EXTRACT( off2 - off1, *pbytes ) )
goto Exit;
}
}
else
{
/* empty index element */
*pbytes = 0;
*pbyte_len = 0;
}
}
else
error = CFF_Err_Invalid_Argument;
Exit:
return error;
}
cff_index_access_element( CFF_Index idx,
FT_UInt element,
FT_Byte** pbytes,
FT_ULong* pbyte_len )
{
FT_Error error = FT_Err_Ok;
if ( idx && idx->count > element )
{
/* compute start and end offsets */
FT_Stream stream = idx->stream;
FT_ULong off1, off2 = 0;
/* load offsets from file or the offset table */
if ( !idx->offsets )
{
FT_ULong pos = element * idx->off_size;
if ( FT_STREAM_SEEK( idx->start + 3 + pos ) )
goto Exit;
off1 = cff_index_read_offset( idx, &error );
if ( error )
goto Exit;
if ( off1 != 0 )
{
do
{
element++;
off2 = cff_index_read_offset( idx, &error );
}
while ( off2 == 0 && element < idx->count );
}
}
else /* use offsets table */
{
off1 = idx->offsets[element];
if ( off1 )
{
do
{
element++;
off2 = idx->offsets[element];
} while ( off2 == 0 && element < idx->count );
}
}
/* XXX: should check off2 does not exceed the end of this entry; */
/* at present, only truncate off2 at the end of this stream */
if ( off2 > stream->size + 1 ||
idx->data_offset > stream->size - off2 + 1 )
{
FT_ERROR(( "cff_index_access_element:"
" offset to next entry (%d)"
" exceeds the end of stream (%d)\n",
off2, stream->size - idx->data_offset + 1 ));
off2 = stream->size - idx->data_offset + 1;
}
/* access element */
if ( off1 && off2 > off1 )
{
*pbyte_len = off2 - off1;
if ( idx->bytes )
{
/* this index was completely loaded in memory, that's easy */
*pbytes = idx->bytes + off1 - 1;
}
else
{
/* this index is still on disk/file, access it through a frame */
if ( FT_STREAM_SEEK( idx->data_offset + off1 - 1 ) ||
FT_FRAME_EXTRACT( off2 - off1, *pbytes ) )
goto Exit;
}
}
else
{
/* empty index element */
*pbytes = 0;
*pbyte_len = 0;
}
}
else
error = FT_THROW( Invalid_Argument );
Exit:
return error;
}