ref: efce08d67c1c2a8bf0d0d58463e754c746433d23
dir: /src/base/ftstream.c/
#include <freetype/internal/ftstream.h>
#include <freetype/internal/ftdebug.h>
#undef FT_COMPONENT
#define FT_COMPONENT trace_stream
BASE_FUNC
void FT_New_Memory_Stream( FT_Library library,
void* base,
unsigned long size,
FT_Stream stream )
{
stream->memory = library->memory;
stream->base = (char*)base;
stream->size = size;
stream->pos = 0;
stream->cursor = 0;
stream->read = 0;
stream->close = 0;
}
BASE_FUNC
FT_Error FT_Seek_Stream( FT_Stream stream,
FT_ULong pos )
{
FT_Error error;
stream->pos = pos;
if (stream->read)
{
if (stream->read( stream, pos, 0, 0 ))
{
error = FT_Err_Invalid_Stream_Operation;
FT_ERROR(( "FT_Seek_Stream:" ));
FT_ERROR(( " invalid i/o, pos = 0x%lx, size = 0x%lx\n",
pos, stream->size ));
}
else
error = FT_Err_Ok;
}
/* note that seeking to the first position after the file is valid */
else if (pos > stream->size)
{
error = FT_Err_Invalid_Stream_Operation;
FT_ERROR(( "FT_Seek_Stream:" ));
FT_ERROR(( " invalid i/o, pos = 0x%lx, size = 0x%lx\n",
pos, stream->size ));
}
else
error = FT_Err_Ok;
return error;
}
BASE_FUNC
FT_Error FT_Skip_Stream( FT_Stream stream,
FT_Long distance )
{
return FT_Seek_Stream( stream, (FT_ULong)(stream->pos + distance) );
}
BASE_FUNC
FT_Long FT_Stream_Pos( FT_Stream stream )
{
return stream->pos;
}
BASE_FUNC
FT_Error FT_Read_Stream( FT_Stream stream,
void* buffer,
FT_ULong count )
{
return FT_Read_Stream_At( stream, stream->pos, buffer, count );
}
BASE_FUNC
FT_Error FT_Read_Stream_At( FT_Stream stream,
FT_ULong pos,
void* buffer,
FT_ULong count )
{
FT_Error error = FT_Err_Ok;
FT_ULong read_bytes;
if (pos >= stream->size)
{
FT_ERROR(( "FT_Read_Stream_At:" ));
FT_ERROR(( " invalid i/o, pos = 0x%lx, size = 0x%lx\n",
pos, stream->size ));
return FT_Err_Invalid_Stream_Operation;
}
if (stream->read)
read_bytes = stream->read( stream, pos, buffer, count );
else
{
read_bytes = stream->size - pos;
if (read_bytes > count)
read_bytes = count;
MEM_Copy( buffer, stream->base + pos, read_bytes );
}
stream->pos = pos + read_bytes;
if (read_bytes < count)
{
FT_ERROR(( "FT_Read_Stream_At:" ));
FT_ERROR(( " invalid read, expected %lu bytes, got %lu",
count, read_bytes ));
error = FT_Err_Invalid_Stream_Operation;
}
return error;
}
BASE_FUNC
FT_Error FT_Access_Frame( FT_Stream stream,
FT_ULong count )
{
FT_Error error = FT_Err_Ok;
FT_ULong read_bytes;
/* check for nested frame access */
FT_Assert( stream && stream->cursor == 0 );
if (stream->read)
{
/* allocate the frame in memory */
FT_Memory memory = stream->memory;
if ( ALLOC( stream->base, count ) )
goto Exit;
/* read it */
read_bytes = stream->read( stream, stream->pos,
stream->base, count );
if (read_bytes < count)
{
FT_ERROR(( "FT_Access_Frame:" ));
FT_ERROR(( " invalid read, expected %lu bytes, got %lu",
count, read_bytes ));
FREE( stream->base );
error = FT_Err_Invalid_Stream_Operation;
}
stream->cursor = stream->base;
stream->limit = stream->cursor + count;
stream->pos += read_bytes;
}
else
{
/* check current and new position */
if (stream->pos >= stream->size || stream->pos + count > stream->size)
{
FT_ERROR(( "FT_Access_Frame:" ));
FT_ERROR(( " invalid i/o, pos = 0x%lx, count = %lu, size = 0x%lx",
stream->pos, count, stream->size ));
error = FT_Err_Invalid_Stream_Operation;
goto Exit;
}
/* set cursor */
stream->cursor = stream->base + stream->pos;
stream->limit = stream->cursor + count;
stream->pos += count;
}
Exit:
return error;
}
BASE_FUNC
void FT_Forget_Frame( FT_Stream stream )
{
/* IMPORTANT: The assertion stream->cursor != 0 was removed, given */
/* that it is possible to access a frame of length 0 in */
/* some weird fonts (usually, when accessing an array of */
/* 0 records, like in some strange kern tables).. */
/* */
/* In this case, the loader code handles the 0-length table */
/* gracefully, however, stream.cursor is really set to 0 by the */
/* FT_Access_Frame call, and this is not an error.. */
/* */
FT_Assert( stream );
if (stream->read)
{
FT_Memory memory = stream->memory;
FREE( stream->base );
}
stream->cursor = 0;
stream->limit = 0;
}
BASE_FUNC
FT_Char FT_Get_Char( FT_Stream stream )
{
FT_Char result;
FT_Assert( stream && stream->cursor );
result = 0;
if (stream->cursor < stream->limit)
result = *stream->cursor++;
return result;
}
BASE_FUNC
FT_Short FT_Get_Short( FT_Stream stream )
{
char* p;
FT_Short result;
FT_Assert( stream && stream->cursor );
result = 0;
p = stream->cursor;
if (p+1 < stream->limit)
result = NEXT_Short(p);
stream->cursor = p;
return result;
}
BASE_FUNC
FT_Long FT_Get_Offset( FT_Stream stream )
{
char* p;
FT_Long result;
FT_Assert( stream && stream->cursor );
result = 0;
p = stream->cursor;
if (p+2 < stream->limit)
result = NEXT_Offset(p);
stream->cursor = p;
return result;
}
BASE_FUNC
FT_Long FT_Get_Long( FT_Stream stream )
{
char* p;
FT_Long result;
FT_Assert( stream && stream->cursor );
result = 0;
p = stream->cursor;
if (p+3 < stream->limit)
result = NEXT_Long(p);
stream->cursor = p;
return result;
}
BASE_FUNC
FT_Char FT_Read_Char( FT_Stream stream,
FT_Error* error )
{
char result = 0;
FT_Assert( stream );
*error = FT_Err_Ok;
if (stream->read)
{
if ( stream->read( stream, stream->pos, &result, 1L ) != 1L )
goto Fail;
}
else
{
if (stream->pos < stream->size)
result = stream->base[stream->pos];
else
goto Fail;
}
stream->pos++;
return result;
Fail:
*error = FT_Err_Invalid_Stream_Operation;
FT_ERROR(( "FT_Read_Char:" ));
FT_ERROR(( " invalid i/o, pos = 0x%lx, size = 0x%lx",
stream->pos, stream->size ));
return 0;
}
BASE_FUNC
FT_Short FT_Read_Short( FT_Stream stream,
FT_Error* error )
{
char reads[2];
char* p = 0;
FT_Short result = 0;
FT_Assert( stream );
*error = FT_Err_Ok;
if (stream->pos+1 < stream->size)
{
if (stream->read)
{
if (stream->read( stream, stream->pos, reads, 2L ) != 2L )
goto Fail;
p = reads;
}
else
{
p = stream->base + stream->pos;
}
if (p)
result = NEXT_Short(p);
}
else goto Fail;
stream->pos += 2;
return result;
Fail:
*error = FT_Err_Invalid_Stream_Operation;
FT_ERROR(( "FT_Read_Short:" ));
FT_ERROR(( " invalid i/o, pos = 0x%lx, size = 0x%lx",
stream->pos, stream->size ));
return 0;
}
BASE_FUNC
FT_Long FT_Read_Offset( FT_Stream stream,
FT_Error* error )
{
char reads[3];
char* p = 0;
FT_Long result = 0;
FT_Assert( stream );
*error = FT_Err_Ok;
if (stream->pos+2 < stream->size)
{
if (stream->read)
{
if (stream->read( stream, stream->pos, reads, 3L ) != 3L )
goto Fail;
p = reads;
}
else
{
p = stream->base + stream->pos;
}
if (p)
result = NEXT_Offset(p);
}
else goto Fail;
stream->pos += 3;
return result;
Fail:
*error = FT_Err_Invalid_Stream_Operation;
FT_ERROR(( "FT_Read_Offset:" ));
FT_ERROR(( " invalid i/o, pos = 0x%lx, size = 0x%lx",
stream->pos, stream->size ));
return 0;
}
BASE_FUNC
FT_Long FT_Read_Long( FT_Stream stream,
FT_Error* error )
{
char reads[4];
char* p = 0;
FT_Long result = 0;
FT_Assert( stream );
*error = FT_Err_Ok;
if (stream->pos+3 < stream->size)
{
if (stream->read)
{
if (stream->read( stream, stream->pos, reads, 4L ) != 4L )
goto Fail;
p = reads;
}
else
{
p = stream->base + stream->pos;
}
if (p)
result = NEXT_Long(p);
}
else goto Fail;
stream->pos += 4;
return result;
Fail:
*error = FT_Err_Invalid_Stream_Operation;
FT_ERROR(( "FT_Read_Long:" ));
FT_ERROR(( " invalid i/o, pos = 0x%lx, size = 0x%lx",
stream->pos, stream->size ));
return 0;
}
BASE_FUNC
FT_Error FT_Read_Fields( FT_Stream stream,
const FT_Frame_Field* fields,
void* structure )
{
FT_Error error;
FT_Bool frame_accessed = 0;
if (!fields || !stream)
return FT_Err_Invalid_Argument;
error = FT_Err_Ok;
do
{
FT_ULong value;
FT_Int sign_shift;
FT_Byte* p;
switch (fields->value)
{
case ft_frame_start: /* access a new frame */
{
error = FT_Access_Frame( stream, fields->offset );
if (error) goto Exit;
frame_accessed = 1;
fields++;
continue; /* loop ! */
}
case ft_frame_byte:
case ft_frame_schar: /* read a single byte */
{
value = GET_Byte();
sign_shift = 24;
break;
}
case ft_frame_short_be:
case ft_frame_ushort_be: /* read a 2-byte big-endian short */
{
value = GET_UShort();
sign_shift = 16;
break;
}
case ft_frame_short_le:
case ft_frame_ushort_le: /* read a 2-byte little-endian short */
{
char* p;
value = 0;
p = stream->cursor;
if (p+1 < stream->limit)
{
value = (FT_UShort)p[0] | ((FT_UShort)p[1] << 8);
stream->cursor += 2;
}
sign_shift = 16;
break;
}
case ft_frame_long_be:
case ft_frame_ulong_be: /* read a 4-byte big-endian long */
{
value = GET_ULong();
sign_shift = 0;
break;
}
case ft_frame_long_le:
case ft_frame_ulong_le: /* read a 4-byte little-endian long */
{
char* p;
value = 0;
p = stream->cursor;
if (p+3 < stream->limit)
{
value = (FT_ULong)p[0] |
((FT_ULong)p[1] << 8) |
((FT_ULong)p[2] << 16) |
((FT_ULong)p[3] << 24);
stream->cursor += 4;
}
sign_shift = 0;
break;
}
case ft_frame_off3_be:
case ft_frame_uoff3_be: /* read a 3-byte big-endian long */
{
value = GET_UOffset();
sign_shift = 8;
break;
}
case ft_frame_off3_le:
case ft_frame_uoff3_le: /* read a 3-byte little-endian long */
{
char* p;
value = 0;
p = stream->cursor;
if (p+3 < stream->limit)
{
value = (FT_ULong)p[0] |
((FT_ULong)p[1] << 8) |
((FT_ULong)p[2] << 16) |
((FT_ULong)p[3] << 24);
stream->cursor += 4;
}
sign_shift = 8;
break;
}
default:
/* otherwise, exit the loop */
goto Exit;
}
/* now, compute the signed value is necessary */
if (fields->value & FT_FRAME_OP_SIGNED)
value = (FT_ULong)((FT_Long)(value << sign_shift) >> sign_shift);
/* finally, store the value in the object */
p = (FT_Byte*)structure + fields->offset;
switch (fields->size)
{
case 1: *(FT_Byte*)p = (FT_Byte) value; break;
case 2: *(FT_UShort*)p = (FT_UShort)value; break;
case 4: *(FT_ULong*)p = (FT_ULong) value; break;
default: ; /* ignore !! */
}
/* go to next field */
fields++;
}
while (1);
Exit:
/* close the frame if it was opened by this read */
if (frame_accessed)
FT_Forget_Frame(stream);
return error;
}