diff options
Diffstat (limited to 'pango/opentype/harfbuzz-stream.c')
| -rw-r--r-- | pango/opentype/harfbuzz-stream.c | 234 |
1 files changed, 234 insertions, 0 deletions
diff --git a/pango/opentype/harfbuzz-stream.c b/pango/opentype/harfbuzz-stream.c new file mode 100644 index 00000000..5746d42f --- /dev/null +++ b/pango/opentype/harfbuzz-stream.c @@ -0,0 +1,234 @@ +/******************************************************************* + * + * Copyright 2005 David Turner, The FreeType Project (www.freetype.org) + * Copyright 2007 Trolltech ASA + * Copyright 2007 Red Hat, Inc + * + * This is part of HarfBuzz, an OpenType Layout engine library. + * + * See the file name COPYING for licensing information. + * + ******************************************************************/ +#include "harfbuzz-impl.h" +#include "harfbuzz-stream-private.h" +#include <stdlib.h> + +#if 0 +#include <stdio.h> +#define LOG(x) _hb_log x + +static void +_hb_log( const char* format, ... ) +{ + va_list ap; + + va_start( ap, format ); + vfprintf( stderr, format, ap ); + va_end( ap ); +} + +#else +#define LOG(x) do {} while (0) +#endif + + +/* only used internally */ +static HB_Pointer +_hb_qalloc( HB_UInt size, + HB_Error *perror ) +{ + HB_Error error = 0; + HB_Pointer block = NULL; + + if ( size > 0 ) + { + block = malloc( size ); + if ( !block ) + error = ERR(HB_Err_Out_Of_Memory); + } + + *perror = error; + return block; +} + +#undef QALLOC /* just in case */ +#define QALLOC(ptr,size) ( (ptr) = _hb_qalloc( (size), &error ), error != 0 ) + +HB_INTERNAL HB_Int +_hb_stream_pos( HB_Stream stream ) +{ + LOG(( "_hb_stream_pos() -> %ld\n", stream->pos )); + return stream->pos; +} + + +HB_INTERNAL HB_Error +_hb_stream_seek( HB_Stream stream, + HB_UInt pos ) +{ + HB_Error error = 0; + + stream->pos = pos; + if ( stream->read ) + { + if ( stream->read( stream, pos, NULL, 0 ) ) + error = ERR(HB_Err_Read_Error); + } + else if ( pos > stream->size ) + error = ERR(HB_Err_Read_Error); + + LOG(( "_hb_stream_seek(%ld) -> 0x%04X\n", pos, error )); + return error; +} + + +HB_INTERNAL HB_Error +_hb_stream_frame_enter( HB_Stream stream, + HB_UInt count ) +{ + HB_Error error = HB_Err_Ok; + HB_UInt read_bytes; + + if ( stream->read ) + { + /* allocate the frame in memory */ + + if ( QALLOC( stream->base, count ) ) + goto Exit; + + /* read it */ + read_bytes = stream->read( stream, stream->pos, + stream->base, count ); + if ( read_bytes < count ) + { + FREE( stream->base ); + error = ERR(HB_Err_Read_Error); + } + stream->cursor = stream->base; + stream->limit = stream->cursor + count; + stream->pos += read_bytes; + } + else + { + /* check new position, watch for overflow */ + if (HB_UNLIKELY (stream->pos + count > stream->size || + stream->pos + count < stream->pos)) + { + error = ERR(HB_Err_Read_Error); + goto Exit; + } + + /* set cursor */ + stream->cursor = stream->base + stream->pos; + stream->limit = stream->cursor + count; + stream->pos += count; + } + +Exit: + LOG(( "_hb_stream_frame_enter(%ld) -> 0x%04X\n", count, error )); + return error; +} + + +HB_INTERNAL void +_hb_stream_frame_exit( HB_Stream stream ) +{ + if ( stream->read ) + { + FREE( stream->base ); + } + stream->cursor = NULL; + stream->limit = NULL; + + LOG(( "_hb_stream_frame_exit()\n" )); +} + + +HB_INTERNAL HB_Error +_hb_face_goto_table( FT_Face face, + HB_UInt the_tag ) +{ + HB_Stream stream = face->stream; + + HB_Error error; + + LOG(( "_hb_face_goto_table( %p, %c%c%c%c, %p )\n", + face, + (int)((the_tag >> 24) & 0xFF), + (int)((the_tag >> 16) & 0xFF), + (int)((the_tag >> 8) & 0xFF), + (int)(the_tag & 0xFF), + stream )); + + if ( !FT_IS_SFNT(face) ) + { + LOG(( "not a SFNT face !!\n" )); + error = ERR(HB_Err_Invalid_Argument); + } + else + { + /* parse the directory table directly, without using + * FreeType's built-in data structures + */ + HB_UInt offset = 0; + HB_UInt count, nn; + + if ( face->num_faces > 1 ) + { + /* deal with TrueType collections */ + LOG(( ">> This is a TrueType Collection\n" )); + + if ( FILE_Seek( 12 + face->face_index*4 ) || + ACCESS_Frame( 4 ) ) + goto Exit; + + offset = GET_ULong(); + + FORGET_Frame(); + } + + LOG(( "TrueType offset = %ld\n", offset )); + + if ( FILE_Seek( offset+4 ) || + ACCESS_Frame( 2 ) ) + goto Exit; + + count = GET_UShort(); + + FORGET_Frame(); + + if ( FILE_Seek( offset+12 ) || + ACCESS_Frame( count*16 ) ) + goto Exit; + + for ( nn = 0; nn < count; nn++ ) + { + HB_UInt tag = GET_ULong(); + HB_UInt checksum = GET_ULong(); + HB_UInt start = GET_ULong(); + HB_UInt size = GET_ULong(); + + HB_UNUSED(checksum); + HB_UNUSED(size); + + if ( tag == the_tag ) + { + LOG(( "TrueType table (start: %ld) (size: %ld)\n", start, size )); + error = _hb_stream_seek( stream, start ); + goto FoundIt; + } + } + error = HB_Err_Not_Covered; + + FoundIt: + FORGET_Frame(); + } + +Exit: + LOG(( "TrueType error=%d\n", error )); + + return error; +} + +#undef QALLOC + |