Edit
kc3-lang/freetype/src/cff/cffparse.c
Werner Lemberg
- src/cff/cffparse.c
-
/***************************************************************************/ /* */ /* cffparse.c */ /* */ /* CFF token stream parser (body) */ /* */ /* Copyright 1996-2001, 2002, 2003, 2004, 2007 by */ /* David Turner, Robert Wilhelm, and Werner Lemberg. */ /* */ /* This file is part of the FreeType project, and may only be used, */ /* modified, and distributed under the terms of the FreeType project */ /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ /* this file you indicate that you have read the license and */ /* understand and accept it fully. */ /* */ /***************************************************************************/ #include <ft2build.h> #include "cffparse.h" #include FT_INTERNAL_STREAM_H #include "cfferrs.h" /*************************************************************************/ /* */ /* The macro FT_COMPONENT is used in trace mode. It is an implicit */ /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */ /* messages during execution. */ /* */ #undef FT_COMPONENT #define FT_COMPONENT trace_cffparse enum { cff_kind_none = 0, cff_kind_num, cff_kind_fixed, cff_kind_fixed_thousand, cff_kind_string, cff_kind_bool, cff_kind_delta, cff_kind_callback, cff_kind_max /* do not remove */ }; /* now generate handlers for the most simple fields */ typedef FT_Error (*CFF_Field_Reader)( CFF_Parser parser ); typedef struct CFF_Field_Handler_ { int kind; int code; FT_UInt offset; FT_Byte size; CFF_Field_Reader reader; FT_UInt array_max; FT_UInt count_offset; } CFF_Field_Handler; FT_LOCAL_DEF( void ) cff_parser_init( CFF_Parser parser, FT_UInt code, void* object ) { FT_MEM_ZERO( parser, sizeof ( *parser ) ); parser->top = parser->stack; parser->object_code = code; parser->object = object; } /* read an integer */ static FT_Long cff_parse_integer( FT_Byte* start, FT_Byte* limit ) { FT_Byte* p = start; FT_Int v = *p++; FT_Long val = 0; if ( v == 28 ) { if ( p + 2 > limit ) goto Bad; val = (FT_Short)( ( (FT_Int)p[0] << 8 ) | p[1] ); p += 2; } else if ( v == 29 ) { if ( p + 4 > limit ) goto Bad; val = ( (FT_Long)p[0] << 24 ) | ( (FT_Long)p[1] << 16 ) | ( (FT_Long)p[2] << 8 ) | p[3]; p += 4; } else if ( v < 247 ) { val = v - 139; } else if ( v < 251 ) { if ( p + 1 > limit ) goto Bad; val = ( v - 247 ) * 256 + p[0] + 108; p++; } else { if ( p + 1 > limit ) goto Bad; val = -( v - 251 ) * 256 - p[0] - 108; p++; } Exit: return val; Bad: val = 0; goto Exit; } /* read a real */ static FT_Fixed cff_parse_real( FT_Byte* start, FT_Byte* limit, FT_Int power_ten ) { FT_Byte* p = start; FT_Long num, divider, result, exponent; FT_Int sign = 0, exponent_sign = 0; FT_UInt nib; FT_UInt phase; result = 0; num = 0; divider = 1; /* first of all, read the integer part */ phase = 4; for (;;) { /* If we entered this iteration with phase == 4, we need to */ /* read a new byte. This also skips past the initial 0x1E. */ if ( phase ) { p++; /* Make sure we don't read past the end. */ if ( p >= limit ) goto Bad; } /* Get the nibble. */ nib = ( p[0] >> phase ) & 0xF; phase = 4 - phase; if ( nib == 0xE ) sign = 1; else if ( nib > 9 ) break; else result = result * 10 + nib; } /* read decimal part, if any */ if ( nib == 0xa ) for (;;) { /* If we entered this iteration with phase == 4, we need */ /* to read a new byte. */ if ( phase ) { p++; /* Make sure we don't read past the end. */ if ( p >= limit ) goto Bad; } /* Get the nibble. */ nib = ( p[0] >> phase ) & 0xF; phase = 4 - phase; if ( nib >= 10 ) break; if ( divider < 10000000L ) { num = num * 10 + nib; divider *= 10; } } /* read exponent, if any */ if ( nib == 12 ) { exponent_sign = 1; nib = 11; } if ( nib == 11 ) { exponent = 0; for (;;) { /* If we entered this iteration with phase == 4, we need */ /* to read a new byte. */ if ( phase ) { p++; /* Make sure we don't read past the end. */ if ( p >= limit ) goto Bad; } /* Get the nibble. */ nib = ( p[0] >> phase ) & 0xF; phase = 4 - phase; if ( nib >= 10 ) break; exponent = exponent * 10 + nib; } if ( exponent_sign ) exponent = -exponent; power_ten += (FT_Int)exponent; } /* raise to power of ten if needed */ while ( power_ten > 0 ) { result = result * 10; num = num * 10; power_ten--; } while ( power_ten < 0 ) { result = result / 10; divider = divider * 10; power_ten++; } /* Move the integer part into the high 16 bits. */ result <<= 16; /* Place the decimal part into the low 16 bits. */ if ( num ) result |= FT_DivFix( num, divider ); if ( sign ) result = -result; Exit: return result; Bad: result = 0; goto Exit; } /* read a number, either integer or real */ static FT_Long cff_parse_num( FT_Byte** d ) { return ( **d == 30 ? ( cff_parse_real ( d[0], d[1], 0 ) >> 16 ) : cff_parse_integer( d[0], d[1] ) ); } /* read a floating point number, either integer or real */ static FT_Fixed cff_parse_fixed( FT_Byte** d ) { return ( **d == 30 ? cff_parse_real ( d[0], d[1], 0 ) : cff_parse_integer( d[0], d[1] ) << 16 ); } /* read a floating point number, either integer or real, */ /* but return 1000 times the number read in. */ static FT_Fixed cff_parse_fixed_thousand( FT_Byte** d ) { return **d == 30 ? cff_parse_real ( d[0], d[1], 3 ) : (FT_Fixed)FT_MulFix( cff_parse_integer( d[0], d[1] ) << 16, 1000 ); } static FT_Error cff_parse_font_matrix( CFF_Parser parser ) { CFF_FontRecDict dict = (CFF_FontRecDict)parser->object; FT_Matrix* matrix = &dict->font_matrix; FT_Vector* offset = &dict->font_offset; FT_UShort* upm = &dict->units_per_em; FT_Byte** data = parser->stack; FT_Error error; FT_Fixed temp; error = CFF_Err_Stack_Underflow; if ( parser->top >= parser->stack + 6 ) { matrix->xx = cff_parse_fixed_thousand( data++ ); matrix->yx = cff_parse_fixed_thousand( data++ ); matrix->xy = cff_parse_fixed_thousand( data++ ); matrix->yy = cff_parse_fixed_thousand( data++ ); offset->x = cff_parse_fixed_thousand( data++ ); offset->y = cff_parse_fixed_thousand( data ); temp = FT_ABS( matrix->yy ); *upm = (FT_UShort)FT_DivFix( 0x10000L, FT_DivFix( temp, 1000 ) ); if ( temp != 0x10000L ) { matrix->xx = FT_DivFix( matrix->xx, temp ); matrix->yx = FT_DivFix( matrix->yx, temp ); matrix->xy = FT_DivFix( matrix->xy, temp ); matrix->yy = FT_DivFix( matrix->yy, temp ); offset->x = FT_DivFix( offset->x, temp ); offset->y = FT_DivFix( offset->y, temp ); } /* note that the offsets must be expressed in integer font units */ offset->x >>= 16; offset->y >>= 16; error = CFF_Err_Ok; } return error; } static FT_Error cff_parse_font_bbox( CFF_Parser parser ) { CFF_FontRecDict dict = (CFF_FontRecDict)parser->object; FT_BBox* bbox = &dict->font_bbox; FT_Byte** data = parser->stack; FT_Error error; error = CFF_Err_Stack_Underflow; if ( parser->top >= parser->stack + 4 ) { bbox->xMin = FT_RoundFix( cff_parse_fixed( data++ ) ); bbox->yMin = FT_RoundFix( cff_parse_fixed( data++ ) ); bbox->xMax = FT_RoundFix( cff_parse_fixed( data++ ) ); bbox->yMax = FT_RoundFix( cff_parse_fixed( data ) ); error = CFF_Err_Ok; } return error; } static FT_Error cff_parse_private_dict( CFF_Parser parser ) { CFF_FontRecDict dict = (CFF_FontRecDict)parser->object; FT_Byte** data = parser->stack; FT_Error error; error = CFF_Err_Stack_Underflow; if ( parser->top >= parser->stack + 2 ) { dict->private_size = cff_parse_num( data++ ); dict->private_offset = cff_parse_num( data ); error = CFF_Err_Ok; } return error; } static FT_Error cff_parse_cid_ros( CFF_Parser parser ) { CFF_FontRecDict dict = (CFF_FontRecDict)parser->object; FT_Byte** data = parser->stack; FT_Error error; error = CFF_Err_Stack_Underflow; if ( parser->top >= parser->stack + 3 ) { dict->cid_registry = (FT_UInt)cff_parse_num ( data++ ); dict->cid_ordering = (FT_UInt)cff_parse_num ( data++ ); dict->cid_supplement = (FT_ULong)cff_parse_num( data ); error = CFF_Err_Ok; } return error; } #define CFF_FIELD_NUM( code, name ) \ CFF_FIELD( code, name, cff_kind_num ) #define CFF_FIELD_FIXED( code, name ) \ CFF_FIELD( code, name, cff_kind_fixed ) #define CFF_FIELD_FIXED_1000( code, name ) \ CFF_FIELD( code, name, cff_kind_fixed_thousand ) #define CFF_FIELD_STRING( code, name ) \ CFF_FIELD( code, name, cff_kind_string ) #define CFF_FIELD_BOOL( code, name ) \ CFF_FIELD( code, name, cff_kind_bool ) #define CFF_FIELD_DELTA( code, name, max ) \ CFF_FIELD( code, name, cff_kind_delta ) #define CFF_FIELD_CALLBACK( code, name ) \ { \ cff_kind_callback, \ code | CFFCODE, \ 0, 0, \ cff_parse_ ## name, \ 0, 0 \ }, #undef CFF_FIELD #define CFF_FIELD( code, name, kind ) \ { \ kind, \ code | CFFCODE, \ FT_FIELD_OFFSET( name ), \ FT_FIELD_SIZE( name ), \ 0, 0, 0 \ }, #undef CFF_FIELD_DELTA #define CFF_FIELD_DELTA( code, name, max ) \ { \ cff_kind_delta, \ code | CFFCODE, \ FT_FIELD_OFFSET( name ), \ FT_FIELD_SIZE_DELTA( name ), \ 0, \ max, \ FT_FIELD_OFFSET( num_ ## name ) \ }, #define CFFCODE_TOPDICT 0x1000 #define CFFCODE_PRIVATE 0x2000 static const CFF_Field_Handler cff_field_handlers[] = { #include "cfftoken.h" { 0, 0, 0, 0, 0, 0, 0 } }; FT_LOCAL_DEF( FT_Error ) cff_parser_run( CFF_Parser parser, FT_Byte* start, FT_Byte* limit ) { FT_Byte* p = start; FT_Error error = CFF_Err_Ok; parser->top = parser->stack; parser->start = start; parser->limit = limit; parser->cursor = start; while ( p < limit ) { FT_UInt v = *p; if ( v >= 27 && v != 31 ) { /* it's a number; we will push its position on the stack */ if ( parser->top - parser->stack >= CFF_MAX_STACK_DEPTH ) goto Stack_Overflow; *parser->top ++ = p; /* now, skip it */ if ( v == 30 ) { /* skip real number */ p++; for (;;) { if ( p >= limit ) goto Syntax_Error; v = p[0] >> 4; if ( v == 15 ) break; v = p[0] & 0xF; if ( v == 15 ) break; p++; } } else if ( v == 28 ) p += 2; else if ( v == 29 ) p += 4; else if ( v > 246 ) p += 1; } else { /* This is not a number, hence it's an operator. Compute its code */ /* and look for it in our current list. */ FT_UInt code; FT_UInt num_args = (FT_UInt) ( parser->top - parser->stack ); const CFF_Field_Handler* field; *parser->top = p; code = v; if ( v == 12 ) { /* two byte operator */ p++; if ( p >= limit ) goto Syntax_Error; code = 0x100 | p[0]; } code = code | parser->object_code; for ( field = cff_field_handlers; field->kind; field++ ) { if ( field->code == (FT_Int)code ) { /* we found our field's handler; read it */ FT_Long val; FT_Byte* q = (FT_Byte*)parser->object + field->offset; /* check that we have enough arguments -- except for */ /* delta encoded arrays, which can be empty */ if ( field->kind != cff_kind_delta && num_args < 1 ) goto Stack_Underflow; switch ( field->kind ) { case cff_kind_bool: case cff_kind_string: case cff_kind_num: val = cff_parse_num( parser->stack ); goto Store_Number; case cff_kind_fixed: val = cff_parse_fixed( parser->stack ); goto Store_Number; case cff_kind_fixed_thousand: val = cff_parse_fixed_thousand( parser->stack ); Store_Number: switch ( field->size ) { case (8 / FT_CHAR_BIT): *(FT_Byte*)q = (FT_Byte)val; break; case (16 / FT_CHAR_BIT): *(FT_Short*)q = (FT_Short)val; break; case (32 / FT_CHAR_BIT): *(FT_Int32*)q = (FT_Int)val; break; default: /* for 64-bit systems */ *(FT_Long*)q = val; } break; case cff_kind_delta: { FT_Byte* qcount = (FT_Byte*)parser->object + field->count_offset; FT_Byte** data = parser->stack; if ( num_args > field->array_max ) num_args = field->array_max; /* store count */ *qcount = (FT_Byte)num_args; val = 0; while ( num_args > 0 ) { val += cff_parse_num( data++ ); switch ( field->size ) { case (8 / FT_CHAR_BIT): *(FT_Byte*)q = (FT_Byte)val; break; case (16 / FT_CHAR_BIT): *(FT_Short*)q = (FT_Short)val; break; case (32 / FT_CHAR_BIT): *(FT_Int32*)q = (FT_Int)val; break; default: /* for 64-bit systems */ *(FT_Long*)q = val; } q += field->size; num_args--; } } break; default: /* callback */ error = field->reader( parser ); if ( error ) goto Exit; } goto Found; } } /* this is an unknown operator, or it is unsupported; */ /* we will ignore it for now. */ Found: /* clear stack */ parser->top = parser->stack; } p++; } Exit: return error; Stack_Overflow: error = CFF_Err_Invalid_Argument; goto Exit; Stack_Underflow: error = CFF_Err_Invalid_Argument; goto Exit; Syntax_Error: error = CFF_Err_Invalid_Argument; goto Exit; } /* END */