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      1 /*
      2  * Copyright  2013  Google, Inc.
      3  *
      4  *  This is part of HarfBuzz, a text shaping library.
      5  *
      6  * Permission is hereby granted, without written agreement and without
      7  * license or royalty fees, to use, copy, modify, and distribute this
      8  * software and its documentation for any purpose, provided that the
      9  * above copyright notice and the following two paragraphs appear in
     10  * all copies of this software.
     11  *
     12  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
     13  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
     14  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
     15  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
     16  * DAMAGE.
     17  *
     18  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
     19  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
     20  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
     21  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
     22  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
     23  *
     24  * Google Author(s): Behdad Esfahbod
     25  */
     26 
     27 #ifndef HB_BUFFER_DESERIALIZE_TEXT_HH
     28 #define HB_BUFFER_DESERIALIZE_TEXT_HH
     29 
     30 #include "hb-private.hh"
     31 
     32 %%{
     33 
     34 machine deserialize_text;
     35 alphtype unsigned char;
     36 write data;
     37 
     38 action clear_item {
     39 	memset (&info, 0, sizeof (info));
     40 	memset (&pos , 0, sizeof (pos ));
     41 }
     42 
     43 action add_item {
     44 	buffer->add_info (info);
     45 	if (buffer->in_error)
     46 	  return false;
     47 	buffer->pos[buffer->len - 1] = pos;
     48 	*end_ptr = p;
     49 }
     50 
     51 action tok {
     52 	tok = p;
     53 }
     54 
     55 action parse_glyph {
     56 	if (!hb_font_glyph_from_string (font,
     57 					tok, p - tok,
     58 					&info.codepoint))
     59 	  return false;
     60 }
     61 
     62 action parse_cluster   { if (!parse_uint (tok, p, &info.cluster )) return false; }
     63 action parse_x_offset  { if (!parse_int  (tok, p, &pos.x_offset )) return false; }
     64 action parse_y_offset  { if (!parse_int  (tok, p, &pos.y_offset )) return false; }
     65 action parse_x_advance { if (!parse_int  (tok, p, &pos.x_advance)) return false; }
     66 action parse_y_advance { if (!parse_int  (tok, p, &pos.y_advance)) return false; }
     67 
     68 unum	= '0' | [1-9] digit*;
     69 num	= '-'? unum;
     70 
     71 glyph_id = unum;
     72 glyph_name = alpha (alnum|'_'|'.'|'-')*;
     73 
     74 glyph	= (glyph_id | glyph_name) >tok %parse_glyph;
     75 cluster	= '=' (unum >tok %parse_cluster);
     76 offsets	= '@' (num >tok %parse_x_offset)   ',' (num >tok %parse_y_offset );
     77 advances= '+' (num >tok %parse_x_advance) (',' (num >tok %parse_y_advance))?;
     78 item	=
     79 	(
     80 		glyph
     81 		cluster?
     82 		offsets?
     83 		advances?
     84 	)
     85 	>clear_item
     86 	%add_item
     87 	;
     88 
     89 main := space* item (space* '|' space* item)* space* ('|'|']')?;
     90 
     91 }%%
     92 
     93 static hb_bool_t
     94 _hb_buffer_deserialize_glyphs_text (hb_buffer_t *buffer,
     95 				    const char *buf,
     96 				    unsigned int buf_len,
     97 				    const char **end_ptr,
     98 				    hb_font_t *font)
     99 {
    100   const char *p = buf, *pe = buf + buf_len;
    101 
    102   /* Ensure we have positions. */
    103   (void) hb_buffer_get_glyph_positions (buffer, NULL);
    104 
    105   while (p < pe && ISSPACE (*p))
    106     p++;
    107   if (p < pe && *p == (buffer->len ? '|' : '['))
    108   {
    109     *end_ptr = ++p;
    110   }
    111 
    112   const char *eof = pe, *tok = NULL;
    113   int cs;
    114   hb_glyph_info_t info;
    115   hb_glyph_position_t pos;
    116   %%{
    117     write init;
    118     write exec;
    119   }%%
    120 
    121   *end_ptr = p;
    122 
    123   return p == pe && *(p-1) != ']';
    124 }
    125 
    126 #endif /* HB_BUFFER_DESERIALIZE_TEXT_HH */
    127