freetype2/src/type1z/t1load.c

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/*******************************************************************
*
* t1load.h 2.0
*
* Type1 Loader.
*
* Copyright 1996-2000 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.
*
*
* This is the new and improved Type 1 data loader for FreeType 2.
* The old loader has several problems: it is slow, complex, difficult
* to maintain, and contains incredible hacks to make it accept some
* ill-formed Type 1 fonts without hiccup-ing. Moreover, about 5%
* of the Type 1 fonts on my machine still aren't loaded correctly
* by it.
*
* This version is much simpler, much faster and also easier to
* read and maintain by a great order of magnitude. The idea behind
* it is to _not_ try to read the Type 1 token stream with a state
* machine (i.e. a Postscript-like interpreter) but rather to perform
* simple pattern-matching.
*
* Indeed, nearly all data definitions follow a simple pattern
* like :
*
* ..... /Field <data> ....
*
* where <data> can be a number, a boolean, a string, or an
* array of numbers. There are a few exceptions, namely the
* encoding, font name, charstrings and subrs and they are
* handled with a special pattern-matching routine.
*
* All other common cases are handled very simply. The matching
* rules are defined in the file "t1tokens.h" through the use
* of several macros calls PARSE_XXXX
*
* This file is included twice here, the first time to generate
* parsing callback functions, the second to generate a table
* of keywords (with pointers to the associated callback).
*
* The function "parse_dict" simply scans *linearly* a given
* dictionary (either the top-level or private one) and calls
* the appropriate callback when it encounters an immediate
* keyword.
*
* This is by far the fastest way one can find to parse and read
* all data :-)
*
* This led to tremendous code size reduction. Note that later,
* the glyph loader will also be _greatly_ simplified, and the
* automatic hinter will replace the clumsy "t1hinter"..
*
******************************************************************/
#include <ftdebug.h>
#include <ftconfig.h>
#include <t1types.h>
#include <t1errors.h>
#include <t1load.h>
#include <stdio.h>
#undef FT_COMPONENT
#define FT_COMPONENT trace_t1load
typedef void (*T1_Parse_Func)( T1_Face face, T1_Loader* loader );
typedef struct T1_KeyWord_
{
const char* name;
T1_Parse_Func parsing;
} T1_KeyWord;
/* some handy macros used to easily define parsing callback functions */
/* each callback is in charge of loading a value and storing it in a */
/* given field of the Type 1 face.. */
#define PARSE_(x) static void parse_##x##( T1_Face face, T1_Loader* loader )
#define PARSE_STRING(s,x) PARSE_(x) \
{ \
FACE.##x = T1_ToString(&loader->parser); \
FT_TRACE2(( "type1.parse_##x##: \"%s\"\n", FACE.##x )); \
}
#define PARSE_NUM(s,x,t) PARSE_(x) \
{ \
FACE.##x = (t)T1_ToInt(&loader->parser); \
FT_TRACE2(( "type1.parse_##x##: \"%d\"\n", FACE.##x )); \
}
#define PARSE_INT(s,x) PARSE_(x) \
{ \
FACE.##x = T1_ToInt(&loader->parser); \
FT_TRACE2(( "type1.parse_##x##: \"%d\"\n", FACE.##x )); \
}
#define PARSE_BOOL(s,x) PARSE_(x) \
{ \
FACE.##x = T1_ToBool(&loader->parser); \
FT_TRACE2(( "type1.parse_##x##: \"%s\"\n", \
FACE.##x ? "true" : "false" )); \
}
#define PARSE_FIXED(s,x) PARSE_(x) \
{ \
FACE.##x = T1_ToFixed(&loader->parser,3); \
FT_TRACE2(( "type1.parse_##x##: \"%f\"\n", FACE.##x/65536.0 )); \
}
#define PARSE_COORDS(s,c,m,x) PARSE_(x) \
{ \
FACE.##c = T1_ToCoordArray(&loader->parser, m, (T1_Short*)FACE.##x ); \
FT_TRACE2(( "type1.parse_##x##\n" )); \
}
#define PARSE_FIXEDS(s,c,m,x) PARSE_(x) \
{ \
FACE.##c = T1_ToFixedArray(&loader->parser, m, (T1_Fixed*)FACE.##x, 3 ); \
FT_TRACE2(( "type1.parse_##x##\n" )); \
}
#define PARSE_COORDS2(s,m,x) PARSE_(x) \
{ \
(void)T1_ToCoordArray( &loader->parser, m, (T1_Short*)&FACE.##x ); \
FT_TRACE2(( "type1.parse_##x##\n" )); \
}
#define PARSE_FIXEDS2(s,m,x) PARSE_(x) \
{ \
(void)T1_ToFixedArray(&loader->parser, m, (T1_Fixed*)&FACE.##x, 3 ); \
FT_TRACE2(( "type1.parse_##x##\n" )); \
}
/* define all parsing callbacks */
#include <t1tokens.h>
static
int is_space( char c )
{
return ( c == ' ' || c == '\t' || c == '\r' || c == '\n' );
}
static
int is_alpha( char c )
{
return ( (c >= 'A' && c <= 'Z') ||
(c >= 'a' && c <= 'z') ||
(c >= '0' && c <= '9') ||
(c == '.') ||
(c == '_') );
}
static
void skip_whitespace( T1_Parser* parser )
{
T1_Byte* cur = parser->cursor;
while ( cur < parser->limit && is_space(*cur) )
cur++;
parser->cursor = cur;
}
static
void skip_blackspace( T1_Parser* parser )
{
T1_Byte* cur = parser->cursor;
while ( cur < parser->limit && !is_space(*cur) )
cur++;
parser->cursor = cur;
}
static
int read_binary_data( T1_Parser* parser, T1_Int *size, T1_Byte* *base )
{
T1_Byte* cur;
T1_Byte* limit = parser->limit;
/* the binary data has the following format */
/* */
/* "size" [white*] RD white ....... ND */
/* */
skip_whitespace(parser);
cur = parser->cursor;
if ( cur < limit && (T1_Byte)(*cur-'0') < 10 )
{
*size = T1_ToInt(parser);
skip_whitespace(parser);
skip_blackspace(parser); /* "RD" or "-|" or something else */
/* there is only one whitespace char after the */
/* "RD" or "-|" token */
*base = parser->cursor + 1;
parser->cursor += *size+1;
return 1;
}
FT_ERROR(( "type1.read_binary_data: invalid size field\n" ));
parser->error = FT_Err_Invalid_File_Format;
return 0;
}
/* we will now define the routines used to handle */
/* the /Encoding, /Subrs and /CharStrings */
/* dictionaries.. */
static
void parse_font_name( T1_Face face, T1_Loader* loader )
{
T1_Parser* parser = &loader->parser;
FT_Error error;
FT_Memory memory = parser->memory;
T1_Int len;
T1_Byte* cur;
T1_Byte* cur2;
T1_Byte* limit;
skip_whitespace(parser);
cur = parser->cursor;
limit = parser->limit;
if ( cur >= limit-1 || *cur != '/' ) return;
cur++;
cur2 = cur;
while (cur2 < limit && is_alpha(*cur2)) cur2++;
len = cur2-cur;
if (len > 0)
{
if ( ALLOC( face->type1.font_name, len+1 ) )
{
parser->error = error;
return;
}
MEM_Copy( face->type1.font_name, cur, len );
face->type1.font_name[len] = '\0';
}
parser->cursor = cur2;
}
static
void parse_font_bbox( T1_Face face, T1_Loader* loader )
{
T1_Parser* parser = &loader->parser;
T1_Short temp[4];
T1_BBox* bbox = &face->type1.font_bbox;
(void)T1_ToCoordArray( parser, 4, temp );
bbox->xMin = temp[0];
bbox->yMin = temp[1];
bbox->xMax = temp[2];
bbox->yMax = temp[3];
}
static
void parse_encoding( T1_Face face, T1_Loader* loader )
{
T1_Parser* parser = &loader->parser;
T1_Byte* cur = parser->cursor;
T1_Byte* limit = parser->limit;
/* skip whitespace */
while (is_space(*cur))
{
cur++;
if (cur >= limit)
{
FT_ERROR(( "type1.parse_encoding: out of bounds !!\n" ));
parser->error = FT_Err_Invalid_File_Format;
return;
}
}
/* if we have a number, then the encoding is an array, */
/* and we must load it now */
if ((T1_Byte)(*cur - '0') < 10)
{
T1_Encoding* encode = &face->type1.encoding;
T1_Int count, n;
T1_Table* char_table = &loader->encoding_table;
FT_Memory memory = parser->memory;
FT_Error error;
/* read the number of entries in the encoding, should be 256 */
count = T1_ToInt( parser );
if (parser->error) return;
/* we use a T1_Table to store our charnames */
encode->num_chars = count;
if ( ALLOC_ARRAY( encode->char_index, count, T1_Short ) ||
ALLOC_ARRAY( encode->char_name, count, T1_String* ) ||
(error = T1_New_Table( char_table, count, memory )) != 0 )
{
parser->error = error;
return;
}
/* now, we will need to read a record of the form */
/* ... charcode /charname ... for each entry in our table */
/* */
/* we simply look for a number followed by an immediate */
/* name. Note that this ignores correctly the sequence */
/* that is often seen in type1 fonts : */
/* */
/* 0 1 255 { 1 index exch /.notdef put } for dup */
/* */
/* used to clean the encoding array before anything else */
/* */
/* we stop when we encounter a "def" */
/* */
cur = parser->cursor;
limit = parser->limit;
n = 0;
for ( ; cur < limit; )
{
T1_Byte c;
c = *cur;
/* we stop when we encounter a 'def' */
if ( c == 'd' && cur+3 < limit )
{
if ( cur[1] == 'e' &&
cur[2] == 'f' &&
is_space(cur[-1]) &&
is_space(cur[3]) )
{
FT_TRACE6(( "encoding end\n" ));
break;
}
}
/* otherwise, we must find a number before anything else */
if ( (T1_Byte)(c-'0') < 10 )
{
T1_Int charcode;
parser->cursor = cur;
charcode = T1_ToInt(parser);
cur = parser->cursor;
/* skip whitespace */
while (cur < limit && is_space(*cur)) cur++;
if (cur < limit && *cur == '/')
{
/* bingo, we have an immediate name - it must be a */
/* character name */
FT_Byte* cur2 = cur+1;
T1_Int len;
while (cur2 < limit && is_alpha(*cur2)) cur2++;
len = cur2-cur-1;
parser->error = T1_Add_Table( char_table, charcode, cur+1, len+1 );
char_table->elements[charcode][len] = '\0';
if (parser->error) return;
cur = cur2;
}
}
else
cur++;
}
face->type1.encoding_type = t1_encoding_array;
parser->cursor = cur;
}
/* Otherwise, we should have either "StandardEncoding" or */
/* "ExpertEncoding" */
else
{
if ( cur+17 < limit &&
strncmp( (const char*)cur, "StandardEncoding", 16 ) == 0 )
face->type1.encoding_type = t1_encoding_standard;
else if ( cur+15 < limit &&
strncmp( (const char*)cur, "ExpertEncoding", 14 ) == 0 )
face->type1.encoding_type = t1_encoding_expert;
else
{
FT_ERROR(( "type1.parse_encoding: invalid token !!\n" ));
parser->error = FT_Err_Invalid_File_Format;
}
}
}
static
void parse_subrs( T1_Face face, T1_Loader* loader )
{
T1_Parser* parser = &loader->parser;
T1_Table* table = &loader->subrs;
FT_Memory memory = parser->memory;
FT_Error error;
T1_Int n;
loader->num_subrs = T1_ToInt( parser );
if (parser->error) return;
/* initialise subrs array */
error = T1_New_Table( table, loader->num_subrs, memory );
if (error) goto Fail;
/* the format is simple : */
/* */
/* "index" + binary data */
/* */
for ( n = 0; n < loader->num_subrs; n++ )
{
T1_Int index, size;
T1_Byte* base;
index = T1_ToInt(parser);
if (!read_binary_data(parser,&size,&base)) return;
T1_Decrypt( base, size, 4330 );
size -= face->type1.private_dict.lenIV;
base += face->type1.private_dict.lenIV;
error = T1_Add_Table( table, index, base, size );
if (error) goto Fail;
}
return;
Fail:
parser->error = error;
}
static
void parse_charstrings( T1_Face face, T1_Loader* loader )
{
T1_Parser* parser = &loader->parser;
T1_Table* code_table = &loader->charstrings;
T1_Table* name_table = &loader->glyph_names;
FT_Memory memory = parser->memory;
FT_Error error;
T1_Byte* cur;
T1_Byte* limit = parser->limit;
T1_Int n;
loader->num_glyphs = T1_ToInt( parser );
if (parser->error) return;
/* initialise tables */
error = T1_New_Table( code_table, loader->num_glyphs, memory ) ||
T1_New_Table( name_table, loader->num_glyphs, memory );
if (error) goto Fail;
n = 0;
for ( ;; )
{
T1_Int size;
T1_Byte* base;
/* the format is simple : */
/* "/glyphname" + binary data */
/* */
/* note that we stop when we find a "def" */
/* */
skip_whitespace(parser);
cur = parser->cursor;
if (cur >= limit) break;
/* we stop when we find a "def" or "end" keyword */
if (*cur == 'd' &&
cur+3 < limit &&
cur[1] == 'e' &&
cur[2] == 'f' )
break;
if (*cur == 'e' &&
cur+3 < limit &&
cur[1] == 'n' &&
cur[2] == 'd' )
break;
if (*cur != '/')
skip_blackspace(parser);
else
{
T1_Byte* cur2 = cur+1;
T1_Int len;
while (cur2 < limit && is_alpha(*cur2)) cur2++;
len = cur2-cur-1;
error = T1_Add_Table( name_table, n, cur+1, len+1 );
if (error) goto Fail;
/* add a trailing zero to the name table */
name_table->elements[n][len] = '\0';
parser->cursor = cur2;
if (!read_binary_data(parser,&size,&base)) return;
T1_Decrypt( base, size, 4330 );
size -= face->type1.private_dict.lenIV;
base += face->type1.private_dict.lenIV;
error = T1_Add_Table( code_table, n, base, size );
if (error) goto Fail;
n++;
if (n >= loader->num_glyphs)
break;
}
}
loader->num_glyphs = n;
return;
Fail:
parser->error = error;
}
#undef PARSE_STRING
#undef PARSE_INT
#undef PARSE_NUM
#undef PARSE_BOOL
#undef PARSE_FIXED
#undef PARSE_COORDS
#undef PARSE_FIXEDS
#undef PARSE_COORDS2
#undef PARSE_FIXEDS2
#undef PARSE_
#define PARSE_(s,x) { s, parse_##x },
#define PARSE_STRING(s,x) PARSE_(s,x)
#define PARSE_INT(s,x) PARSE_(s,x)
#define PARSE_NUM(s,x,t) PARSE_(s,x)
#define PARSE_BOOL(s,x) PARSE_(s,x)
#define PARSE_FIXED(s,x) PARSE_(s,x)
#define PARSE_COORDS(s,c,m,x) PARSE_(s,x)
#define PARSE_FIXEDS(s,c,m,x) PARSE_(s,x)
#define PARSE_COORDS2(s,m,x) PARSE_(s,x)
#define PARSE_FIXEDS2(s,m,x) PARSE_(s,x)
static
const T1_KeyWord t1_keywords[] =
{
#include <t1tokens.h>
/* now add the special functions... */
{ "FontName", parse_font_name },
{ "FontBBox", parse_font_bbox },
{ "Encoding", parse_encoding },
{ "Subrs", parse_subrs },
{ "CharStrings", parse_charstrings },
{ 0, 0 }
};
static
T1_Error parse_dict( T1_Face face,
T1_Loader* loader,
T1_Byte* base,
T1_Long size )
{
T1_Parser* parser = &loader->parser;
parser->cursor = base;
parser->limit = base + size;
parser->error = 0;
{
T1_Byte* cur = base;
T1_Byte* limit = cur + size;
for ( ;cur < limit; cur++ )
{
/* look for immediates */
if (*cur == '/' && cur+2 < limit)
{
T1_Byte* cur2;
T1_Int len;
cur ++;
cur2 = cur;
while (cur2 < limit && is_alpha(*cur2)) cur2++;
len = cur2-cur;
if (len > 0 && len < 20)
{
/* now, compare the immediate name to the keyword table */
T1_KeyWord* keyword = (T1_KeyWord*)t1_keywords;
for (;;)
{
T1_Byte* name;
name = (T1_Byte*)keyword->name;
if (!name) break;
if ( cur[0] == name[0] &&
len == (T1_Int)strlen((const char*)name) )
{
T1_Int n;
for ( n = 1; n < len; n++ )
if (cur[n] != name[n])
break;
if (n >= len)
{
/* we found it - run the parsing callback !! */
parser->cursor = cur2;
skip_whitespace( parser );
keyword->parsing( face, loader );
if (parser->error)
return parser->error;
cur = parser->cursor;
break;
}
}
keyword++;
}
}
}
}
}
return parser->error;
}
static
void t1_init_loader( T1_Loader* loader, T1_Face face )
{
UNUSED(face);
MEM_Set( loader, 0, sizeof(*loader) );
loader->num_glyphs = 0;
loader->num_chars = 0;
/* initialize the tables - simply set their 'init' field to 0 */
loader->encoding_table.init = 0;
loader->charstrings.init = 0;
loader->glyph_names.init = 0;
loader->subrs.init = 0;
}
static
void t1_done_loader( T1_Loader* loader )
{
T1_Parser* parser = &loader->parser;
/* finalize tables */
T1_Release_Table( &loader->encoding_table );
T1_Release_Table( &loader->charstrings );
T1_Release_Table( &loader->glyph_names );
T1_Release_Table( &loader->subrs );
/* finalize parser */
T1_Done_Parser( parser );
}
LOCAL_FUNC
T1_Error T1_Open_Face( T1_Face face )
{
T1_Loader loader;
T1_Parser* parser;
T1_Font* type1 = &face->type1;
FT_Error error;
t1_init_loader( &loader, face );
/* default lenIV */
type1->private_dict.lenIV = 4;
parser = &loader.parser;
error = T1_New_Parser( parser, face->root.stream, face->root.memory );
if (error) goto Exit;
error = parse_dict( face, &loader, parser->base_dict, parser->base_len );
if (error) goto Exit;
error = T1_Get_Private_Dict( parser );
if (error) goto Exit;
error = parse_dict( face, &loader, parser->private_dict, parser->private_len );
if (error) goto Exit;
/* now, propagate the subrs, charstrings and glyphnames tables */
/* to the Type1 data */
type1->num_glyphs = loader.num_glyphs;
if ( !loader.subrs.init )
{
FT_ERROR(( "T1.Open_Face: no subrs array in face !!\n" ));
error = FT_Err_Invalid_File_Format;
}
if ( !loader.charstrings.init )
{
FT_ERROR(( "T1.Open_Face: no charstrings array in face !!\n" ));
error = FT_Err_Invalid_File_Format;
}
loader.subrs.init = 0;
type1->num_subrs = loader.num_subrs;
type1->subrs_block = loader.subrs.block;
type1->subrs = loader.subrs.elements;
type1->subrs_len = loader.subrs.lengths;
loader.charstrings.init = 0;
type1->charstrings_block = loader.charstrings.block;
type1->charstrings = loader.charstrings.elements;
type1->charstrings_len = loader.charstrings.lengths;
/* we copy the glyph names "block" and "elements" fields */
/* but the "lengths" field must be released later.. */
type1->glyph_names_block = loader.glyph_names.block;
type1->glyph_names = (T1_String**)loader.glyph_names.elements;
loader.glyph_names.block = 0;
loader.glyph_names.elements = 0;
/* we must now build type1.encoding when we have a custom */
/* array.. */
if ( type1->encoding_type == t1_encoding_array )
{
T1_Int charcode, index, min_char, max_char;
T1_Byte* char_name;
T1_Byte* glyph_name;
/* OK, we do the following : for each element in the encoding */
/* table, lookup the index of the glyph having the same name */
/* the index is then stored in type1.encoding.char_index, and */
/* a the name to type1.encoding.char_name */
min_char = +32000;
max_char = -32000;
charcode = 0;
for ( ; charcode < loader.encoding_table.num_elems; charcode++ )
{
type1->encoding.char_index[charcode] = 0;
type1->encoding.char_name [charcode] = ".notdef";
char_name = loader.encoding_table.elements[charcode];
if (char_name)
for ( index = 0; index < type1->num_glyphs; index++ )
{
glyph_name = (T1_Byte*)type1->glyph_names[index];
if ( strcmp( (const char*)char_name,
(const char*)glyph_name ) == 0 )
{
type1->encoding.char_index[charcode] = index;
type1->encoding.char_name [charcode] = (char*)glyph_name;
if (charcode < min_char) min_char = charcode;
if (charcode > max_char) max_char = charcode;
break;
}
}
}
type1->encoding.code_first = min_char;
type1->encoding.code_last = max_char;
type1->encoding.num_chars = loader.num_chars;
}
Exit:
t1_done_loader( &loader );
return error;
}