1 /*
2  * Copyright © 2016  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_OT_POST_TABLE_HH
28 #define HB_OT_POST_TABLE_HH
29 
30 #include "hb-open-type.hh"
31 
32 #define HB_STRING_ARRAY_NAME format1_names
33 #define HB_STRING_ARRAY_LIST "hb-ot-post-macroman.hh"
34 #include "hb-string-array.hh"
35 #undef HB_STRING_ARRAY_LIST
36 #undef HB_STRING_ARRAY_NAME
37 
38 /*
39  * post -- PostScript
40  * https://docs.microsoft.com/en-us/typography/opentype/spec/post
41  */
42 #define HB_OT_TAG_post HB_TAG('p','o','s','t')
43 
44 
45 namespace OT {
46 
47 
48 struct postV2Tail
49 {
50   friend struct post;
51 
sanitizeOT::postV2Tail52   bool sanitize (hb_sanitize_context_t *c) const
53   {
54     TRACE_SANITIZE (this);
55     return_trace (glyphNameIndex.sanitize (c));
56   }
57 
58   protected:
59   Array16Of<HBUINT16>	glyphNameIndex;	/* This is not an offset, but is the
60 					 * ordinal number of the glyph in 'post'
61 					 * string tables. */
62 /*UnsizedArrayOf<HBUINT8>
63 			namesX;*/	/* Glyph names with length bytes [variable]
64 					 * (a Pascal string). */
65 
66   public:
67   DEFINE_SIZE_ARRAY (2, glyphNameIndex);
68 };
69 
70 struct post
71 {
72   static constexpr hb_tag_t tableTag = HB_OT_TAG_post;
73 
serializeOT::post74   void serialize (hb_serialize_context_t *c) const
75   {
76     post *post_prime = c->allocate_min<post> ();
77     if (unlikely (!post_prime))  return;
78 
79     memcpy (post_prime, this, post::min_size);
80     post_prime->version.major = 3; // Version 3 does not have any glyph names.
81   }
82 
subsetOT::post83   bool subset (hb_subset_context_t *c) const
84   {
85     TRACE_SUBSET (this);
86     post *post_prime = c->serializer->start_embed<post> ();
87     if (unlikely (!post_prime)) return_trace (false);
88 
89     serialize (c->serializer);
90 
91     return_trace (true);
92   }
93 
94   struct accelerator_t
95   {
initOT::post::accelerator_t96     void init (hb_face_t *face)
97     {
98       index_to_offset.init ();
99 
100       table = hb_sanitize_context_t ().reference_table<post> (face);
101       unsigned int table_length = table.get_length ();
102 
103       version = table->version.to_int ();
104       if (version != 0x00020000) return;
105 
106       const postV2Tail &v2 = table->v2X;
107 
108       glyphNameIndex = &v2.glyphNameIndex;
109       pool = &StructAfter<uint8_t> (v2.glyphNameIndex);
110 
111       const uint8_t *end = (const uint8_t *) (const void *) table + table_length;
112       for (const uint8_t *data = pool;
113 	   index_to_offset.length < 65535 && data < end && data + *data < end;
114 	   data += 1 + *data)
115 	index_to_offset.push (data - pool);
116     }
finiOT::post::accelerator_t117     void fini ()
118     {
119       index_to_offset.fini ();
120       free (gids_sorted_by_name.get ());
121       table.destroy ();
122     }
123 
get_glyph_nameOT::post::accelerator_t124     bool get_glyph_name (hb_codepoint_t glyph,
125 			 char *buf, unsigned int buf_len) const
126     {
127       hb_bytes_t s = find_glyph_name (glyph);
128       if (!s.length) return false;
129       if (!buf_len) return true;
130       unsigned int len = hb_min (buf_len - 1, s.length);
131       strncpy (buf, s.arrayZ, len);
132       buf[len] = '\0';
133       return true;
134     }
135 
get_glyph_from_nameOT::post::accelerator_t136     bool get_glyph_from_name (const char *name, int len,
137 			      hb_codepoint_t *glyph) const
138     {
139       unsigned int count = get_glyph_count ();
140       if (unlikely (!count)) return false;
141 
142       if (len < 0) len = strlen (name);
143 
144       if (unlikely (!len)) return false;
145 
146     retry:
147       uint16_t *gids = gids_sorted_by_name.get ();
148 
149       if (unlikely (!gids))
150       {
151 	gids = (uint16_t *) malloc (count * sizeof (gids[0]));
152 	if (unlikely (!gids))
153 	  return false; /* Anything better?! */
154 
155 	for (unsigned int i = 0; i < count; i++)
156 	  gids[i] = i;
157 	hb_qsort (gids, count, sizeof (gids[0]), cmp_gids, (void *) this);
158 
159 	if (unlikely (!gids_sorted_by_name.cmpexch (nullptr, gids)))
160 	{
161 	  free (gids);
162 	  goto retry;
163 	}
164       }
165 
166       hb_bytes_t st (name, len);
167       auto* gid = hb_bsearch (st, gids, count, sizeof (gids[0]), cmp_key, (void *) this);
168       if (gid)
169       {
170 	*glyph = *gid;
171 	return true;
172       }
173 
174       return false;
175     }
176 
177     hb_blob_ptr_t<post> table;
178 
179     protected:
180 
get_glyph_countOT::post::accelerator_t181     unsigned int get_glyph_count () const
182     {
183       if (version == 0x00010000)
184 	return format1_names_length;
185 
186       if (version == 0x00020000)
187 	return glyphNameIndex->len;
188 
189       return 0;
190     }
191 
cmp_gidsOT::post::accelerator_t192     static int cmp_gids (const void *pa, const void *pb, void *arg)
193     {
194       const accelerator_t *thiz = (const accelerator_t *) arg;
195       uint16_t a = * (const uint16_t *) pa;
196       uint16_t b = * (const uint16_t *) pb;
197       return thiz->find_glyph_name (b).cmp (thiz->find_glyph_name (a));
198     }
199 
cmp_keyOT::post::accelerator_t200     static int cmp_key (const void *pk, const void *po, void *arg)
201     {
202       const accelerator_t *thiz = (const accelerator_t *) arg;
203       const hb_bytes_t *key = (const hb_bytes_t *) pk;
204       uint16_t o = * (const uint16_t *) po;
205       return thiz->find_glyph_name (o).cmp (*key);
206     }
207 
find_glyph_nameOT::post::accelerator_t208     hb_bytes_t find_glyph_name (hb_codepoint_t glyph) const
209     {
210       if (version == 0x00010000)
211       {
212 	if (glyph >= format1_names_length)
213 	  return hb_bytes_t ();
214 
215 	return format1_names (glyph);
216       }
217 
218       if (version != 0x00020000 || glyph >= glyphNameIndex->len)
219 	return hb_bytes_t ();
220 
221       unsigned int index = glyphNameIndex->arrayZ[glyph];
222       if (index < format1_names_length)
223 	return format1_names (index);
224       index -= format1_names_length;
225 
226       if (index >= index_to_offset.length)
227 	return hb_bytes_t ();
228       unsigned int offset = index_to_offset[index];
229 
230       const uint8_t *data = pool + offset;
231       unsigned int name_length = *data;
232       data++;
233 
234       return hb_bytes_t ((const char *) data, name_length);
235     }
236 
237     private:
238     uint32_t version;
239     const Array16Of<HBUINT16> *glyphNameIndex;
240     hb_vector_t<uint32_t> index_to_offset;
241     const uint8_t *pool;
242     hb_atomic_ptr_t<uint16_t *> gids_sorted_by_name;
243   };
244 
has_dataOT::post245   bool has_data () const { return version.to_int (); }
246 
sanitizeOT::post247   bool sanitize (hb_sanitize_context_t *c) const
248   {
249     TRACE_SANITIZE (this);
250     return_trace (likely (c->check_struct (this) &&
251 			  (version.to_int () == 0x00010000 ||
252 			   (version.to_int () == 0x00020000 && v2X.sanitize (c)) ||
253 			   version.to_int () == 0x00030000)));
254   }
255 
256   public:
257   FixedVersion<>version;		/* 0x00010000 for version 1.0
258 					 * 0x00020000 for version 2.0
259 					 * 0x00025000 for version 2.5 (deprecated)
260 					 * 0x00030000 for version 3.0 */
261   HBFixed	italicAngle;		/* Italic angle in counter-clockwise degrees
262 					 * from the vertical. Zero for upright text,
263 					 * negative for text that leans to the right
264 					 * (forward). */
265   FWORD		underlinePosition;	/* This is the suggested distance of the top
266 					 * of the underline from the baseline
267 					 * (negative values indicate below baseline).
268 					 * The PostScript definition of this FontInfo
269 					 * dictionary key (the y coordinate of the
270 					 * center of the stroke) is not used for
271 					 * historical reasons. The value of the
272 					 * PostScript key may be calculated by
273 					 * subtracting half the underlineThickness
274 					 * from the value of this field. */
275   FWORD		underlineThickness;	/* Suggested values for the underline
276 					   thickness. */
277   HBUINT32	isFixedPitch;		/* Set to 0 if the font is proportionally
278 					 * spaced, non-zero if the font is not
279 					 * proportionally spaced (i.e. monospaced). */
280   HBUINT32	minMemType42;		/* Minimum memory usage when an OpenType font
281 					 * is downloaded. */
282   HBUINT32	maxMemType42;		/* Maximum memory usage when an OpenType font
283 					 * is downloaded. */
284   HBUINT32	minMemType1;		/* Minimum memory usage when an OpenType font
285 					 * is downloaded as a Type 1 font. */
286   HBUINT32	maxMemType1;		/* Maximum memory usage when an OpenType font
287 					 * is downloaded as a Type 1 font. */
288   postV2Tail	v2X;
289   DEFINE_SIZE_MIN (32);
290 };
291 
292 struct post_accelerator_t : post::accelerator_t {};
293 
294 } /* namespace OT */
295 
296 
297 #endif /* HB_OT_POST_TABLE_HH */
298