ref: 2282f341d6aae03f4c8d09a0922a7ba6f25e7643
dir: /src/otlayout/otlcommn.c/
#include "otlayout.h"
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** COVERAGE TABLE *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
OTL_LOCALDEF( void )
otl_coverage_validate( OTL_Bytes table,
OTL_Validator valid )
{
OTL_Bytes p;
OTL_UInt format;
if ( table + 4 > valid->limit )
OTL_INVALID_TOO_SHORT;
format = OTL_NEXT_UShort(p);
switch (format)
{
case 1:
{
OTL_UInt count = OTL_NEXT_UShort(p);
if ( p + count*2 >= valid->limit )
OTL_INVALID_TOO_SHORT;
/* XXX: check glyph indices */
}
break;
case 2:
{
OTL_UInt n, num_ranges = OTL_NEXT_UShort(p);
OTL_UInt start, end, start_cover, total = 0, last = 0;
if ( p + num_ranges*6 >= valid->limit )
OTL_INVALID_TOO_SHORT;
for ( n = 0; n < num_ranges; n++ )
{
start = OTL_NEXT_UShort(p);
end = OTL_NEXT_UShort(p);
start_cover = OTL_NEXT_UShort(p);
if ( start > end || start_cover != total )
OTL_INVALID_DATA;
if ( n > 0 && start <= last )
OTL_INVALID_DATA;
total += (end - start + 1);
last = end;
}
}
break;
default:
OTL_INVALID_FORMAT;
}
}
OTL_LOCALDEF( OTL_UInt )
otl_coverage_get_count( OTL_Bytes table )
{
OTL_Bytes p = table;
OTL_UInt format = OTL_NEXT_UShort(p);
OTL_UInt count = OTL_NEXT_UShort(p);
OTL_UInt result = 0;
switch ( format )
{
case 1:
return count;
case 2:
{
OTL_UInt start, end;
for ( ; count > 0; count-- )
{
start = OTL_NEXT_UShort(p);
end = OTL_NEXT_UShort(p);
p += 2; /* skip start_index */
result += ( end - start + 1 );
}
}
break;
default:
;
}
return result;
}
OTL_LOCALDEF( OTL_Int )
otl_coverage_get_index( OTL_Bytes table,
OTL_UInt glyph_index )
{
OTL_Bytes p = table;
OTL_UInt format = OTL_NEXT_UShort(p);
OTL_UInt count = OTL_NEXT_UShort(p);
switch ( format )
{
case 1:
{
OTL_UInt min = 0, max = count, mid, gindex;
table += 4;
while ( min < max )
{
mid = ( min + max ) >> 1;
p = table + 2*mid;
gindex = OTL_PEEK_UShort(p);
if ( glyph_index == gindex )
return (OTL_Int)mid;
if ( glyph_index < gindex )
max = mid;
else
min = mid + 1;
}
}
break;
case 2:
{
OTL_UInt min = 0, max = count, mid;
OTL_UInt start, end, delta, start_cover;
table += 4;
while ( min < max )
{
mid = ( min + max ) >> 1;
p = table + 6*mid;
start = OTL_NEXT_UShort(p);
end = OTL_NEXT_UShort(p);
if ( glyph_index < start )
max = mid;
else if ( glyph_index > end )
min = mid + 1;
else
return (OTL_Int)( glyph_index + OTL_NEXT_UShort(p) - start );
}
}
break;
default:
;
}
return -1;
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** CLASS DEFINITION TABLE *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
OTL_LOCALDEF( void )
otl_class_definition_validate( OTL_Bytes table,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt format;
if ( p + 4 > valid->limit )
OTL_INVALID_TOO_SHORT;
format = OTL_NEXT_UShort(p);
switch ( format )
{
case 1:
{
OTL_UInt count, start = OTL_NEXT_UShort(p);
if ( p + 2 > valid->limit )
OTL_INVALID_TOO_SHORT;
count = OTL_NEXT_UShort(p);
if ( p + count*2 > valid->limit )
OTL_INVALID_TOO_SHORT;
/* XXX: check glyph indices */
}
break;
case 2:
{
OTL_UInt n, num_ranges = OTL_NEXT_UShort(p);
OTL_UInt start, end, value, last = 0;
if ( p + num_ranges*6 > valid->limit )
OTL_INVALID_TOO_SHORT;
for ( n = 0; n < num_ranges; n++ )
{
start = OTL_NEXT_UShort(p);
end = OTL_NEXT_UShort(p);
value = OTL_NEXT_UShort(p); /* ignored */
if ( start > end || ( n > 0 && start <= last ) )
OTL_INVALID_DATA;
last = end;
}
}
break;
default:
OTL_INVALID_FORMAT;
}
}
OTL_LOCALDEF( OTL_UInt )
otl_class_definition_get_value( OTL_Bytes table,
OTL_UInt glyph_index )
{
OTL_Bytes p = table;
OTL_UInt format = OTL_NEXT_UShort(p);
switch ( format )
{
case 1:
{
OTL_UInt start = OTL_NEXT_UShort(p);
OTL_UInt count = OTL_NEXT_UShort(p);
OTL_UInt index = (OTL_UInt)( glyph_index - start );
if ( index < count )
{
p += 2*index;
return OTL_PEEK_UShort(p);
}
}
break;
case 2:
{
OTL_UInt count = OTL_NEXT_UShort(p);
OTL_UInt min = 0, max = count, mid, gindex;
table += 4;
while ( min < max )
{
mid = ( min + max ) >> 1;
p = table + 6*mid;
start = OTL_NEXT_UShort(p);
end = OTL_NEXT_UShort(p);
if ( glyph_index < start )
max = mid;
else if ( glyph_index > end )
min = mid+1;
else
return OTL_PEEK_UShort(p);
}
}
break;
default:
;
}
return 0;
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** DEVICE TABLE *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
OTL_LOCALDEF( void )
otl_device_table_validate( OTL_Bytes table,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt start, end, count, format, count;
if ( p + 8 > valid->limit )
OTL_INVALID_TOO_SHORT;
start = OTL_NEXT_UShort(p);
end = OTL_NEXT_UShort(p);
format = OTL_NEXT_UShort(p);
if ( format < 1 || format > 3 || end < start )
OTL_INVALID_DATA;
count = (OTL_UInt)( end - start + 1 );
if ( p + ((1 << format)*count)/8> valid->limit )
OTL_INVALID_TOO_SHORT;
}
OTL_LOCALDEF( OTL_UInt )
otl_device_table_get_start( OTL_Bytes table )
{
OTL_Bytes p = table;
return OTL_PEEK_UShort(p);
}
OTL_LOCALDEF( OTL_UInt )
otl_device_table_get_end( OTL_Bytes table )
{
OTL_Bytes p = table + 2;
return OTL_PEEK_UShort(p);
}
OTL_LOCALDEF( OTL_Int )
otl_device_table_get_delta( OTL_Bytes table,
OTL_UInt size )
{
OTL_Bytes p = table;
OTL_Int result = 0;
OTL_UInt start, end, format, index, value;
start = OTL_NEXT_UShort(p);
end = OTL_NEXT_UShort(p);
format = OTL_NEXT_UShort(p);
if ( size >= start && size <= end )
{
/* we could do that with clever bit operations, but a switch is simply */
/* much simpler to understand and maintain !! */
/* */
switch ( format )
{
case 1:
{
index = (OTL_UInt)(( size - start )*2);
p += (index/16);
value = OTL_PEEK_UShort(p);
shift = index & 15;
result = (OTL_Short)(value << shift) >> (14-shift);
}
break;
case 2:
{
index = (OTL_UInt)(( size - start )*4);
p += (index/16);
value = OTL_PEEK_UShort(p);
shift = index & 15;
result = (OTL_Short)(value << shift) >> (12-shift);
}
break;
case 3:
{
index = (OTL_UInt)(( size - start )*8);
p += (index/16);
value = OTL_PEEK_UShort(p);
shift = index & 15;
result = (OTL_Short)(value << shift) >> (8-shift);
}
break;
default:
;
}
}
return result;
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** LOOKUP LISTS *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
OTL_LOCALDEF( void )
otl_lookup_validate( OTL_Bytes table,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt num_tables;
if ( table + 6 > valid->limit )
OTL_INVALID_TOO_SHORT;
p += 4;
num_tables = OTL_NEXT_UShort(p);
if ( p + num_tables*2 > valid->limit )
OTL_INVALID_TOO_SHORT;
for ( ; num_tables > 0; num_tables-- )
{
offset = OTL_NEXT_UShort(p);
if ( table + offset >= valid->limit )
OTL_INVALID_OFFSET;
}
/* XXX: check sub-tables ?? */
}
OTL_LOCALDEF( OTL_UInt )
otl_lookup_get_count( OTL_Bytes table )
{
OTL_Bytes p = table + 4;
return OTL_PEEK_UShort(p);
}
OTL_LOCALDEF( OTL_Bytes )
otl_lookup_get_table( OTL_Bytes table,
OTL_UInt index )
{
OTL_Bytes p, result = NULL;
OTL_UInt count;
p = table + 4;
count = OTL_NEXT_UShort(p);
if ( index < count )
{
p += index*2;
result = table + OTL_PEEK_UShort(p);
}
return result;
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** LOOKUP LISTS *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
OTL_LOCALDEF( void )
otl_lookup_list_validate( OTL_Bytes table,
OTL_Validator valid )
{
OTL_Bytes p = table, q;
OTL_UInt num_lookups, offset;
if ( p + 2 > valid->limit )
OTL_INVALID_TOO_SHORT;
num_lookups = OTL_NEXT_UShort(p);
if ( p + num_lookups*2 > valid->limit )
OTL_INVALID_TOO_SHORT;
for ( ; num_lookups > 0; num_lookups-- )
{
offset = OTL_NEXT_UShort(p);
otl_lookup_validate( table + offset, valid );
}
}
OTL_LOCALDEF( OTL_UInt )
otl_lookup_list_get_count( OTL_Bytes table )
{
OTL_Bytes p = table;
return OTL_PEEK_UShort(p);
}
OTL_LOCALDEF( OTL_Bytes )
otl_lookup_list_get_lookup( OTL_Bytes table,
OTL_UInt index )
{
OTL_Bytes p, result = 0;
OTL_UInt count;
p = table;
count = OTL_NEXT_UShort(p);
if ( index < count )
{
p += index*2;
result = table + OTL_PEEK_UShort(p);
}
return result;
}
OTL_LOCALDEF( OTL_Bytes )
otl_lookup_list_get_table( OTL_Bytes table,
OTL_UInt lookup_index,
OTL_UInt table_index )
{
OTL_Bytes result = NULL;
result = otl_lookup_list_get_lookup( table, lookup_index );
if ( result )
result = otl_lookup_get_table( result, table_index );
return result;
}
OTL_LOCALDEF( void )
otl_lookup_list_foreach( OTL_Bytes table,
OTL_ForeachFunc func,
OTL_Pointer func_data )
{
OTL_Bytes p = table;
OTL_UInt count = OTL_NEXT_UShort(p);
for ( ; count > 0; count-- )
func( table + OTL_NEXT_USHORT(p), func_data );
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** FEATURES *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
OTL_LOCALDEF( void )
otl_feature_validate( OTL_Bytes table,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt feat_params, num_lookups;
if ( p + 4 > valid->limit )
OTL_INVALID_TOO_SHORT;
feat_params = OTL_NEXT_UShort(p); /* ignored */
num_lookups = OTL_NEXT_UShort(p);
if ( p + num_lookups*2 > valid->limit )
OTL_INVALID_TOO_SHORT;
/* XXX: check lookup indices */
}
OTL_LOCALDEF( OTL_UInt )
otl_feature_get_count( OTL_Bytes table )
{
OTL_Bytes p = table + 4;
return OTL_PEEK_UShort(p);
}
OTL_LOCALDEF( OTL_UInt )
otl_feature_get_lookups( OTL_Bytes table,
OTL_UInt start,
OTL_UInt count,
OTL_UInt *lookups )
{
OTL_Bytes p;
OTL_UInt num_features, result = 0;
p = table + 4;
num_features = OTL_NEXT_UShort(p);
p += start*2;
for ( ; count > 0 && start < num_features; count--, start++ )
{
lookups[0] = OTL_NEXT_UShort(p);
lookups++;
result++;
}
return result;
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** FEATURE LIST *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
OTL_LOCALDEF( void )
otl_feature_list_validate( OTL_Bytes table,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt num_features, offset;
if ( table + 2 > valid->limit )
OTL_INVALID_TOO_SHORT;
num_features = OTL_NEXT_UShort(p);
if ( p + num_features*2 > valid->limit )
OTL_INVALID_TOO_SHORT;
for ( ; num_features > 0; num_features-- )
{
p += 4; /* skip tag */
offset = OTL_NEXT_UShort(p);
otl_feature_table_validate( table + offset, valid );
}
}
OTL_LOCALDEF( OTL_UInt )
otl_feature_list_get_count( OTL_Bytes table )
{
OTL_Bytes p = table;
return OTL_PEEK_UShort(p);
}
OTL_LOCALDEF( OTL_Bytes )
otl_feature_list_get_feature( OTL_Bytes table,
OTL_UInt index )
{
OTL_Bytes p, result = NULL;
OTL_UInt count;
p = table;
count = OTL_NEXT_UShort(p);
if ( index < count )
{
p += index*2;
result = table + OTL_PEEK_UShort(p);
}
return result;
}
OTL_LOCALDEF( void )
otl_feature_list_foreach( OTL_Bytes table,
OTL_ForeachFunc func,
OTL_Pointer func_data )
{
OTL_Bytes p;
OTL_UInt count;
p = table;
count = OTL_NEXT_UShort(p);
for ( ; count > 0; count-- )
func( table + OTL_NEXT_UShort(p), func_data );
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
OTL_LOCALDEF( void )
otl_lang_validate( OTL_Bytes table,
OTL_Validator valid )
{
OTL_Bytes p = table;
OTL_UInt lookup_order;
OTL_UInt req_feature;
OTL_UInt num_features;
if ( table + 6 >= valid->limit )
OTL_INVALID_TOO_SHORT;
lookup_order = OTL_NEXT_UShort(p);
req_feature = OTL_NEXT_UShort(p);
num_features = OTL_NEXT_UShort(p);
/* XXX: check req_feature if not 0xFFFFU */
if ( p + 2*num_features >= valid->limit )
OTL_INVALID_TOO_SHORT;
/* XXX: check features indices !! */
}
OTL_LOCALDEF( OTL_UInt )
otl_lang_get_count( OTL_Bytes table )
{
OTL_Bytes p = table + 4;
return OTL_PEEK_UShort(p);
}
OTL_LOCALDEF( OTL_UInt )
otl_lang_get_features( OTL_Bytes table,
OTL_UInt start,
OTL_UInt count,
OTL_UInt *features )
{
OTL_Bytes p = table + 4;
OTL_UInt num_features = OTL_NEXT_UShort(p);
OTL_UInt result = 0;
p += start*2;
for ( ; count > 0 && start < num_features; start++, count-- )
{
features[0] = OTL_NEXT_UShort(p);
features++;
result++;
}
return result;
}
OTL_LOCALDEF( OTL_UInt )
otl_lang_get_req_feature( OTL_Bytes table )
{
OTL_Bytes p = table + 2;
return OTL_PEEK_UShort(p);
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
OTL_LOCALDEF( void )
otl_script_table_validate( OTL_Bytes table,
OTL_Validator valid )
{
OTL_UInt default_lang;
OTL_Bytes p = table;
if ( table + 4 > valid->limit )
OTL_INVALID_TOO_SHORT;
default_lang = OTL_NEXT_UShort(p);
num_langs = OTL_NEXT_UShort(p);
if ( default_lang != 0 )
{
if ( table + default_lang >= valid->limit )
OTL_INVALID_OFFSET;
}
if ( p + num_langs*6 >= valid->limit )
OTL_INVALID_OFFSET;
for ( ; num_langs > 0; num_langs-- )
{
OTL_UInt offset;
p += 4; /* skip tag */
offset = OTL_NEXT_UShort(p);
otl_lang_validate( table + offset, valid );
}
}
OTL_LOCALDEF( void )
otl_script_list_validate( OTL_Bytes list,
OTL_Validator valid )
{
OTL_UInt num_scripts;
OTL_Bytes p = list;
if ( list + 2 > valid->limit )
OTL_INVALID_TOO_SHORT;
num_scripts = OTL_NEXT_UShort(p);
if ( p + num_scripts*6 > valid->limit )
OTL_INVALID_TOO_SHORT;
for ( ; num_scripts > 0; num_scripts-- )
{
OTL_UInt offset;
p += 4; /* skip tag */
offset = OTL_NEXT_UShort(p);
otl_script_table_validate( list + offset, valid );
}
}