Handle malformed `loca' table entries.

* docs/TODO: Add some bugs which should be fixed.

* include/freetype/internal/tttypes.h (TT_FaceRec): Add `glyf_len'
element.

* src/truetype/ttpload.c (tt_face_load_loca): Get length of `glyf'
table.
(tt_face_get_location): Fix computation of `asize' for malformed
`loca' entries.
This commit is contained in:
Werner Lemberg 2005-05-05 07:44:20 +00:00
parent 750fa961c6
commit 5452fbe39d
3 changed files with 64 additions and 11 deletions

View File

@ -1,15 +1,30 @@
2005-05-05 Werner Lemberg <wl@gnu.org>
Handle malformed `loca' table entries.
* docs/TODO: Add some bugs which should be fixed.
* include/freetype/internal/tttypes.h (TT_FaceRec): Add `glyf_len'
element.
* src/truetype/ttpload.c (tt_face_load_loca): Get length of `glyf'
table.
(tt_face_get_location): Fix computation of `asize' for malformed
`loca' entries.
2005-05-01 David Turner <david@freetype.org>
* Jamfile: removing otvalid from the list of compiled modules
* include/freetype/internal/ftserv.h: added compiler pragmas to get rid
of annoying warnings with Visual C++ compiler in maximum warning mode
* src/autofit/afhints.c, src/autofit/aflatin.c, src/base/ftstroke.c,
src/bdf/bdfdrivr.c, src/cache/ftcbasic.c, src/cache/ftccmap.c,
src/cache/ftcmanag.c, src/cff/cffload.c, src/cid/cidload.c,
src/lzw/zopen.c, src/otvalid/otvgdef.c, src/pcf/pcfread.c,
src/sfnt/sfobjs.c, src/truetype/ttgxvar.c: removing compiler warnings
* Jamfile: Remove `otvalid' from the list of compiled modules.
* include/freetype/internal/ftserv.h: Add compiler pragmas to get
rid of annoying warnings with Visual C++ compiler in maximum warning
mode.
* src/autofit/afhints.c, src/autofit/aflatin.c, src/base/ftstroke.c,
src/bdf/bdfdrivr.c, src/cache/ftcbasic.c, src/cache/ftccmap.c,
src/cache/ftcmanag.c, src/cff/cffload.c, src/cid/cidload.c,
src/lzw/zopen.c, src/otvalid/otvgdef.c, src/pcf/pcfread.c,
src/sfnt/sfobjs.c, src/truetype/ttgxvar.c: Remove compiler warnings.
2005-04-28 Werner Lemberg <wl@gnu.org>

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@ -1136,6 +1136,9 @@ FT_BEGIN_HEADER
/* glyph data within the `glyf' table. */
/* Ignored for Type 2 font faces. */
/* */
/* glyf_len :: The length of the `glyf' table. Needed */
/* for malformed `loca' tables. */
/* */
/* font_program_size :: Size in bytecodes of the face's font */
/* program. 0 if none defined. Ignored for */
/* Type 2 fonts. */
@ -1298,6 +1301,8 @@ FT_BEGIN_HEADER
FT_Long* glyph_locations;
#endif
FT_ULong glyf_len;
/* the font program, if any */
FT_ULong font_program_size;
FT_Byte* font_program;

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@ -68,6 +68,11 @@
FT_ULong table_len;
/* we need the size of the `glyf' table for malformed `loca' tables */
error = face->goto_table( face, TTAG_glyf, stream, &face->glyf_len );
if ( error )
goto Exit;
FT_TRACE2(( "Locations " ));
error = face->goto_table( face, TTAG_loca, stream, &table_len );
if ( error )
@ -152,7 +157,16 @@
}
}
*asize = (FT_UInt)( pos2 - pos1 );
/* It isn't mentioned explicitly that the `loca' table must be */
/* ordered, but implicitly it refers to the length of an entry */
/* as the difference between the current and the next position. */
/* Anyway, there do exist (malformed) fonts which don't obey */
/* this rule, so we are only able to provide an upper bound for */
/* the size. */
if ( pos2 > pos1 )
*asize = (FT_UInt)( pos2 - pos1 );
else
*asize = (FT_UInt)( face->glyf_len - pos1 );
return pos1;
}
@ -182,6 +196,11 @@
FT_ULong table_len;
/* we need the size of the `glyf' table for malformed `loca' tables */
error = face->goto_table( face, TTAG_glyf, stream, &face->glyf_len );
if ( error )
goto Exit;
FT_TRACE2(( "Locations " ));
LongOffsets = face->header.Index_To_Loc_Format;
@ -259,7 +278,21 @@
count = 0;
if ( gindex < (FT_UInt)face->num_locations - 1 )
count = (FT_UInt)( face->glyph_locations[gindex + 1] - offset );
{
FT_ULong offset1 = face->glyph_locations[gindex + 1];
/* It isn't mentioned explicitly that the `loca' table must be */
/* ordered, but implicitly it refers to the length of an entry */
/* as the difference between the current and the next position. */
/* Anyway, there do exist (malformed) fonts which don't obey */
/* this rule, so we are only able to provide an upper bound for */
/* the size. */
if ( offset1 > offset )
count = (FT_UInt)( offset1 - offset );
else
count = (FT_UInt)( face->glyf_len - offset );
}
*asize = count;
return offset;