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Diffstat (limited to 'src/freetype/t1decode.c')
| -rw-r--r-- | src/freetype/t1decode.c | 479 |
1 files changed, 479 insertions, 0 deletions
diff --git a/src/freetype/t1decode.c b/src/freetype/t1decode.c new file mode 100644 index 0000000..ab68274 --- /dev/null +++ b/src/freetype/t1decode.c @@ -0,0 +1,479 @@ +/***************************************************************************/ +/* */ +/* t1decode.c */ +/* */ +/* PostScript Type 1 decoding routines (body). */ +/* */ +/* Copyright 2000-2018 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 FT_INTERNAL_CALC_H +#include FT_INTERNAL_DEBUG_H +#include FT_INTERNAL_POSTSCRIPT_HINTS_H +#include FT_INTERNAL_HASH_H +#include FT_OUTLINE_H + +#include "t1decode.h" +#include "psobjs.h" + +#include "psauxerr.h" + +/* ensure proper sign extension */ +#define Fix2Int( f ) ( (FT_Int)(FT_Short)( (f) >> 16 ) ) + + /*************************************************************************/ + /* */ + /* 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_t1decode + + + typedef enum T1_Operator_ + { + op_none = 0, + op_endchar, + op_hsbw, + op_seac, + op_sbw, + op_closepath, + op_hlineto, + op_hmoveto, + op_hvcurveto, + op_rlineto, + op_rmoveto, + op_rrcurveto, + op_vhcurveto, + op_vlineto, + op_vmoveto, + op_dotsection, + op_hstem, + op_hstem3, + op_vstem, + op_vstem3, + op_div, + op_callothersubr, + op_callsubr, + op_pop, + op_return, + op_setcurrentpoint, + op_unknown15, + + op_max /* never remove this one */ + + } T1_Operator; + + + static + const FT_Int t1_args_count[op_max] = + { + 0, /* none */ + 0, /* endchar */ + 2, /* hsbw */ + 5, /* seac */ + 4, /* sbw */ + 0, /* closepath */ + 1, /* hlineto */ + 1, /* hmoveto */ + 4, /* hvcurveto */ + 2, /* rlineto */ + 2, /* rmoveto */ + 6, /* rrcurveto */ + 4, /* vhcurveto */ + 1, /* vlineto */ + 1, /* vmoveto */ + 0, /* dotsection */ + 2, /* hstem */ + 6, /* hstem3 */ + 2, /* vstem */ + 6, /* vstem3 */ + 2, /* div */ + -1, /* callothersubr */ + 1, /* callsubr */ + 0, /* pop */ + 0, /* return */ + 2, /* setcurrentpoint */ + 2 /* opcode 15 (undocumented and obsolete) */ + }; + + + /*************************************************************************/ + /* */ + /* <Function> */ + /* t1_lookup_glyph_by_stdcharcode_ps */ + /* */ + /* <Description> */ + /* Looks up a given glyph by its StandardEncoding charcode. Used to */ + /* implement the SEAC Type 1 operator in the Adobe engine */ + /* */ + /* <Input> */ + /* face :: The current face object. */ + /* */ + /* charcode :: The character code to look for. */ + /* */ + /* <Return> */ + /* A glyph index in the font face. Returns -1 if the corresponding */ + /* glyph wasn't found. */ + /* */ + FT_LOCAL_DEF( FT_Int ) + t1_lookup_glyph_by_stdcharcode_ps( PS_Decoder* decoder, + FT_Int charcode ) + { + FT_UInt n; + const FT_String* glyph_name; + FT_Service_PsCMaps psnames = decoder->psnames; + + + /* check range of standard char code */ + if ( charcode < 0 || charcode > 255 ) + return -1; + + glyph_name = psnames->adobe_std_strings( + psnames->adobe_std_encoding[charcode]); + + for ( n = 0; n < decoder->num_glyphs; n++ ) + { + FT_String* name = (FT_String*)decoder->glyph_names[n]; + + + if ( name && + name[0] == glyph_name[0] && + ft_strcmp( name, glyph_name ) == 0 ) + return (FT_Int)n; + } + + return -1; + } + + + /*************************************************************************/ + /* */ + /* <Function> */ + /* t1_decoder_parse_metrics */ + /* */ + /* <Description> */ + /* Parses a given Type 1 charstrings program to extract width */ + /* */ + /* <Input> */ + /* decoder :: The current Type 1 decoder. */ + /* */ + /* charstring_base :: The base address of the charstring stream. */ + /* */ + /* charstring_len :: The length in bytes of the charstring stream. */ + /* */ + /* <Return> */ + /* FreeType error code. 0 means success. */ + /* */ + FT_LOCAL_DEF( FT_Error ) + t1_decoder_parse_metrics( T1_Decoder decoder, + FT_Byte* charstring_base, + FT_UInt charstring_len ) + { + T1_Decoder_Zone zone; + FT_Byte* ip; + FT_Byte* limit; + T1_Builder builder = &decoder->builder; + + + /* First of all, initialize the decoder */ + decoder->top = decoder->stack; + decoder->zone = decoder->zones; + zone = decoder->zones; + + builder->parse_state = T1_Parse_Start; + + FT_TRACE4(( "\n" + "Start charstring: get width\n" )); + + zone->base = charstring_base; + limit = zone->limit = charstring_base + charstring_len; + ip = zone->cursor = zone->base; + + /* now, execute loop */ + while ( ip < limit ) + { + FT_Long* top = decoder->top; + T1_Operator op = op_none; + FT_Int32 value = 0; + + + /*********************************************************************/ + /* */ + /* Decode operator or operand */ + /* */ + /* */ + + /* first of all, decompress operator or value */ + switch ( *ip++ ) + { + case 1: + case 3: + case 4: + case 5: + case 6: + case 7: + case 8: + case 9: + case 10: + case 11: + case 14: + case 15: + case 21: + case 22: + case 30: + case 31: + goto No_Width; + + case 13: + op = op_hsbw; + break; + + case 12: + if ( ip >= limit ) + { + FT_ERROR(( "t1_decoder_parse_metrics:" + " invalid escape (12+EOF)\n" )); + goto Syntax_Error; + } + + switch ( *ip++ ) + { + case 7: + op = op_sbw; + break; + + default: + goto No_Width; + } + break; + + case 255: /* four bytes integer */ + if ( ip + 4 > limit ) + { + FT_ERROR(( "t1_decoder_parse_metrics:" + " unexpected EOF in integer\n" )); + goto Syntax_Error; + } + + value = (FT_Int32)( ( (FT_UInt32)ip[0] << 24 ) | + ( (FT_UInt32)ip[1] << 16 ) | + ( (FT_UInt32)ip[2] << 8 ) | + (FT_UInt32)ip[3] ); + ip += 4; + + /* According to the specification, values > 32000 or < -32000 must */ + /* be followed by a `div' operator to make the result be in the */ + /* range [-32000;32000]. We expect that the second argument of */ + /* `div' is not a large number. Additionally, we don't handle */ + /* stuff like `<large1> <large2> <num> div <num> div' or */ + /* <large1> <large2> <num> div div'. This is probably not allowed */ + /* anyway. */ + if ( value > 32000 || value < -32000 ) + { + FT_ERROR(( "t1_decoder_parse_metrics:" + " large integer found for width\n" )); + goto Syntax_Error; + } + else + { + value = (FT_Int32)( (FT_UInt32)value << 16 ); + } + + break; + + default: + if ( ip[-1] >= 32 ) + { + if ( ip[-1] < 247 ) + value = (FT_Int32)ip[-1] - 139; + else + { + if ( ++ip > limit ) + { + FT_ERROR(( "t1_decoder_parse_metrics:" + " unexpected EOF in integer\n" )); + goto Syntax_Error; + } + + if ( ip[-2] < 251 ) + value = ( ( ip[-2] - 247 ) * 256 ) + ip[-1] + 108; + else + value = -( ( ( ip[-2] - 251 ) * 256 ) + ip[-1] + 108 ); + } + + value = (FT_Int32)( (FT_UInt32)value << 16 ); + } + else + { + FT_ERROR(( "t1_decoder_parse_metrics:" + " invalid byte (%d)\n", ip[-1] )); + goto Syntax_Error; + } + } + + /*********************************************************************/ + /* */ + /* Push value on stack, or process operator */ + /* */ + /* */ + if ( op == op_none ) + { + if ( top - decoder->stack >= T1_MAX_CHARSTRINGS_OPERANDS ) + { + FT_ERROR(( "t1_decoder_parse_metrics: stack overflow\n" )); + goto Syntax_Error; + } + + *top++ = value; + decoder->top = top; + } + else /* general operator */ + { + FT_Int num_args = t1_args_count[op]; + + + FT_ASSERT( num_args >= 0 ); + + if ( top - decoder->stack < num_args ) + goto Stack_Underflow; + + top -= num_args; + + switch ( op ) + { + case op_hsbw: + FT_TRACE4(( " hsbw" )); + + builder->parse_state = T1_Parse_Have_Width; + + builder->left_bearing.x = ADD_LONG( builder->left_bearing.x, + top[0] ); + + builder->advance.x = top[1]; + builder->advance.y = 0; + + /* we only want to compute the glyph's metrics */ + /* (lsb + advance width), not load the rest of */ + /* it; so exit immediately */ + return FT_Err_Ok; + + case op_sbw: + FT_TRACE4(( " sbw" )); + + builder->parse_state = T1_Parse_Have_Width; + + builder->left_bearing.x = ADD_LONG( builder->left_bearing.x, + top[0] ); + builder->left_bearing.y = ADD_LONG( builder->left_bearing.y, + top[1] ); + + builder->advance.x = top[2]; + builder->advance.y = top[3]; + + /* we only want to compute the glyph's metrics */ + /* (lsb + advance width), not load the rest of */ + /* it; so exit immediately */ + return FT_Err_Ok; + + default: + FT_ERROR(( "t1_decoder_parse_metrics:" + " unhandled opcode %d\n", op )); + goto Syntax_Error; + } + + } /* general operator processing */ + + } /* while ip < limit */ + + FT_TRACE4(( "..end..\n\n" )); + + No_Width: + FT_ERROR(( "t1_decoder_parse_metrics:" + " no width, found op %d instead\n", + ip[-1] )); + Syntax_Error: + return FT_THROW( Syntax_Error ); + + Stack_Underflow: + return FT_THROW( Stack_Underflow ); + } + + + /* initialize T1 decoder */ + FT_LOCAL_DEF( FT_Error ) + t1_decoder_init( T1_Decoder decoder, + FT_Face face, + FT_Size size, + FT_GlyphSlot slot, + FT_Byte** glyph_names, + PS_Blend blend, + FT_Bool hinting, + FT_Render_Mode hint_mode, + T1_Decoder_Callback parse_callback ) + { + FT_ZERO( decoder ); + + /* retrieve PSNames interface from list of current modules */ + { + FT_Service_PsCMaps psnames; + + + FT_FACE_FIND_GLOBAL_SERVICE( face, psnames, POSTSCRIPT_CMAPS ); + if ( !psnames ) + { + FT_ERROR(( "t1_decoder_init:" + " the `psnames' module is not available\n" )); + return FT_THROW( Unimplemented_Feature ); + } + + decoder->psnames = psnames; + } + + t1_builder_init( &decoder->builder, face, size, slot, hinting ); + + /* decoder->buildchar and decoder->len_buildchar have to be */ + /* initialized by the caller since we cannot know the length */ + /* of the BuildCharArray */ + + decoder->num_glyphs = (FT_UInt)face->num_glyphs; + decoder->glyph_names = glyph_names; + decoder->hint_mode = hint_mode; + decoder->blend = blend; + decoder->parse_callback = parse_callback; + + decoder->funcs = t1_decoder_funcs; + + return FT_Err_Ok; + } + + + /* finalize T1 decoder */ + FT_LOCAL_DEF( void ) + t1_decoder_done( T1_Decoder decoder ) + { + FT_Memory memory = decoder->builder.memory; + + + t1_builder_done( &decoder->builder ); + + if ( decoder->cf2_instance.finalizer ) + { + decoder->cf2_instance.finalizer( decoder->cf2_instance.data ); + FT_FREE( decoder->cf2_instance.data ); + } + } + + +/* END */ |