1 /*
2  * Copyright © 2017  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_DEBUG_HH
28 #define HB_DEBUG_HH
29 
30 #include "hb.hh"
31 #include "hb-atomic.hh"
32 #include "hb-algs.hh"
33 
34 
35 #ifndef HB_DEBUG
36 #define HB_DEBUG 0
37 #endif
38 
39 
40 /*
41  * Global runtime options.
42  */
43 
44 struct hb_options_t
45 {
46   bool unused : 1; /* In-case sign bit is here. */
47   bool initialized : 1;
48   bool uniscribe_bug_compatible : 1;
49   bool aat : 1;
50 };
51 
52 union hb_options_union_t {
53   int i;
54   hb_options_t opts;
55 };
56 static_assert ((sizeof (hb_atomic_int_t) >= sizeof (hb_options_union_t)), "");
57 
58 HB_INTERNAL void
59 _hb_options_init ();
60 
61 extern HB_INTERNAL hb_atomic_int_t _hb_options;
62 
63 static inline hb_options_t
hb_options()64 hb_options ()
65 {
66 #ifdef HB_NO_GETENV
67   return hb_options_t ();
68 #endif
69   /* Make a local copy, so we can access bitfield threadsafely. */
70   hb_options_union_t u;
71   u.i = _hb_options.get_relaxed ();
72 
73   if (unlikely (!u.i))
74   {
75     _hb_options_init ();
76     u.i = _hb_options.get_relaxed ();
77   }
78 
79   return u.opts;
80 }
81 
82 
83 /*
84  * Debug output (needs enabling at compile time.)
85  */
86 
87 static inline bool
_hb_debug(unsigned int level,unsigned int max_level)88 _hb_debug (unsigned int level,
89 	   unsigned int max_level)
90 {
91   return level < max_level;
92 }
93 
94 #define DEBUG_LEVEL_ENABLED(WHAT, LEVEL) (_hb_debug ((LEVEL), HB_DEBUG_##WHAT))
95 #define DEBUG_ENABLED(WHAT) (DEBUG_LEVEL_ENABLED (WHAT, 0))
96 
97 static inline void
_hb_print_func(const char * func)98 _hb_print_func (const char *func)
99 {
100   if (func)
101   {
102     unsigned int func_len = strlen (func);
103     /* Skip "static" */
104     if (0 == strncmp (func, "static ", 7))
105       func += 7;
106     /* Skip "typename" */
107     if (0 == strncmp (func, "typename ", 9))
108       func += 9;
109     /* Skip return type */
110     const char *space = strchr (func, ' ');
111     if (space)
112       func = space + 1;
113     /* Skip parameter list */
114     const char *paren = strchr (func, '(');
115     if (paren)
116       func_len = paren - func;
117     fprintf (stderr, "%.*s", func_len, func);
118   }
119 }
120 
121 template <int max_level> static inline void
122 _hb_debug_msg_va (const char *what,
123 		  const void *obj,
124 		  const char *func,
125 		  bool indented,
126 		  unsigned int level,
127 		  int level_dir,
128 		  const char *message,
129 		  va_list ap) HB_PRINTF_FUNC(7, 0);
130 template <int max_level> static inline void
_hb_debug_msg_va(const char * what,const void * obj,const char * func,bool indented,unsigned int level,int level_dir,const char * message,va_list ap)131 _hb_debug_msg_va (const char *what,
132 		  const void *obj,
133 		  const char *func,
134 		  bool indented,
135 		  unsigned int level,
136 		  int level_dir,
137 		  const char *message,
138 		  va_list ap)
139 {
140   if (!_hb_debug (level, max_level))
141     return;
142 
143   fprintf (stderr, "%-10s", what ? what : "");
144 
145   if (obj)
146     fprintf (stderr, "(%*p) ", (unsigned int) (2 * sizeof (void *)), obj);
147   else
148     fprintf (stderr, " %*s  ", (unsigned int) (2 * sizeof (void *)), "");
149 
150   if (indented) {
151 #define VBAR	"\342\224\202"	/* U+2502 BOX DRAWINGS LIGHT VERTICAL */
152 #define VRBAR	"\342\224\234"	/* U+251C BOX DRAWINGS LIGHT VERTICAL AND RIGHT */
153 #define DLBAR	"\342\225\256"	/* U+256E BOX DRAWINGS LIGHT ARC DOWN AND LEFT */
154 #define ULBAR	"\342\225\257"	/* U+256F BOX DRAWINGS LIGHT ARC UP AND LEFT */
155 #define LBAR	"\342\225\264"	/* U+2574 BOX DRAWINGS LIGHT LEFT */
156     static const char bars[] =
157       VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR
158       VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR
159       VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR
160       VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR
161       VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR;
162     fprintf (stderr, "%2u %s" VRBAR "%s",
163 	     level,
164 	     bars + sizeof (bars) - 1 - hb_min ((unsigned int) sizeof (bars) - 1, (unsigned int) (sizeof (VBAR) - 1) * level),
165 	     level_dir ? (level_dir > 0 ? DLBAR : ULBAR) : LBAR);
166   } else
167     fprintf (stderr, "   " VRBAR LBAR);
168 
169   _hb_print_func (func);
170 
171   if (message)
172   {
173     fprintf (stderr, ": ");
174     vfprintf (stderr, message, ap);
175   }
176 
177   fprintf (stderr, "\n");
178 }
179 template <> inline void HB_PRINTF_FUNC(7, 0)
_hb_debug_msg_va(const char * what HB_UNUSED,const void * obj HB_UNUSED,const char * func HB_UNUSED,bool indented HB_UNUSED,unsigned int level HB_UNUSED,int level_dir HB_UNUSED,const char * message HB_UNUSED,va_list ap HB_UNUSED)180 _hb_debug_msg_va<0> (const char *what HB_UNUSED,
181 		     const void *obj HB_UNUSED,
182 		     const char *func HB_UNUSED,
183 		     bool indented HB_UNUSED,
184 		     unsigned int level HB_UNUSED,
185 		     int level_dir HB_UNUSED,
186 		     const char *message HB_UNUSED,
187 		     va_list ap HB_UNUSED) {}
188 
189 template <int max_level> static inline void
190 _hb_debug_msg (const char *what,
191 	       const void *obj,
192 	       const char *func,
193 	       bool indented,
194 	       unsigned int level,
195 	       int level_dir,
196 	       const char *message,
197 	       ...) HB_PRINTF_FUNC(7, 8);
198 template <int max_level> static inline void HB_PRINTF_FUNC(7, 8)
_hb_debug_msg(const char * what,const void * obj,const char * func,bool indented,unsigned int level,int level_dir,const char * message,...)199 _hb_debug_msg (const char *what,
200 	       const void *obj,
201 	       const char *func,
202 	       bool indented,
203 	       unsigned int level,
204 	       int level_dir,
205 	       const char *message,
206 	       ...)
207 {
208   va_list ap;
209   va_start (ap, message);
210   _hb_debug_msg_va<max_level> (what, obj, func, indented, level, level_dir, message, ap);
211   va_end (ap);
212 }
213 template <> inline void
214 _hb_debug_msg<0> (const char *what HB_UNUSED,
215 		  const void *obj HB_UNUSED,
216 		  const char *func HB_UNUSED,
217 		  bool indented HB_UNUSED,
218 		  unsigned int level HB_UNUSED,
219 		  int level_dir HB_UNUSED,
220 		  const char *message HB_UNUSED,
221 		  ...) HB_PRINTF_FUNC(7, 8);
222 template <> inline void HB_PRINTF_FUNC(7, 8)
_hb_debug_msg(const char * what HB_UNUSED,const void * obj HB_UNUSED,const char * func HB_UNUSED,bool indented HB_UNUSED,unsigned int level HB_UNUSED,int level_dir HB_UNUSED,const char * message HB_UNUSED,...)223 _hb_debug_msg<0> (const char *what HB_UNUSED,
224 		  const void *obj HB_UNUSED,
225 		  const char *func HB_UNUSED,
226 		  bool indented HB_UNUSED,
227 		  unsigned int level HB_UNUSED,
228 		  int level_dir HB_UNUSED,
229 		  const char *message HB_UNUSED,
230 		  ...) {}
231 
232 #define DEBUG_MSG_LEVEL(WHAT, OBJ, LEVEL, LEVEL_DIR, ...)	_hb_debug_msg<HB_DEBUG_##WHAT> (#WHAT, (OBJ), nullptr,    true, (LEVEL), (LEVEL_DIR), __VA_ARGS__)
233 #define DEBUG_MSG(WHAT, OBJ, ...) 				_hb_debug_msg<HB_DEBUG_##WHAT> (#WHAT, (OBJ), nullptr,    false, 0, 0, __VA_ARGS__)
234 #define DEBUG_MSG_FUNC(WHAT, OBJ, ...)				_hb_debug_msg<HB_DEBUG_##WHAT> (#WHAT, (OBJ), HB_FUNC, false, 0, 0, __VA_ARGS__)
235 
236 
237 /*
238  * Printer
239  */
240 
241 template <typename T>
242 struct hb_printer_t {
printhb_printer_t243   const char *print (const T&) { return "something"; }
244 };
245 
246 template <>
247 struct hb_printer_t<bool> {
printhb_printer_t248   const char *print (bool v) { return v ? "true" : "false"; }
249 };
250 
251 template <>
252 struct hb_printer_t<hb_empty_t> {
printhb_printer_t253   const char *print (hb_empty_t) { return ""; }
254 };
255 
256 
257 /*
258  * Trace
259  */
260 
261 template <typename T>
_hb_warn_no_return(bool returned)262 static inline void _hb_warn_no_return (bool returned)
263 {
264   if (unlikely (!returned)) {
265     fprintf (stderr, "OUCH, returned with no call to return_trace().  This is a bug, please report.\n");
266   }
267 }
268 template <>
_hb_warn_no_return(bool returned HB_UNUSED)269 /*static*/ inline void _hb_warn_no_return<hb_empty_t> (bool returned HB_UNUSED)
270 {}
271 
272 template <int max_level, typename ret_t>
273 struct hb_auto_trace_t
274 {
hb_auto_trace_thb_auto_trace_t275   explicit inline hb_auto_trace_t (unsigned int *plevel_,
276 				   const char *what_,
277 				   const void *obj_,
278 				   const char *func,
279 				   const char *message,
280 				   ...) HB_PRINTF_FUNC(6, 7)
281 				   : plevel (plevel_), what (what_), obj (obj_), returned (false)
282   {
283     if (plevel) ++*plevel;
284 
285     va_list ap;
286     va_start (ap, message);
287     _hb_debug_msg_va<max_level> (what, obj, func, true, plevel ? *plevel : 0, +1, message, ap);
288     va_end (ap);
289   }
~hb_auto_trace_thb_auto_trace_t290   ~hb_auto_trace_t ()
291   {
292     _hb_warn_no_return<ret_t> (returned);
293     if (!returned) {
294       _hb_debug_msg<max_level> (what, obj, nullptr, true, plevel ? *plevel : 1, -1, " ");
295     }
296     if (plevel) --*plevel;
297   }
298 
299   template <typename T>
rethb_auto_trace_t300   T ret (T&& v,
301 	 const char *func = "",
302 	 unsigned int line = 0)
303   {
304     if (unlikely (returned)) {
305       fprintf (stderr, "OUCH, double calls to return_trace().  This is a bug, please report.\n");
306       return hb_forward<T> (v);
307     }
308 
309     _hb_debug_msg<max_level> (what, obj, func, true, plevel ? *plevel : 1, -1,
310 			      "return %s (line %d)",
311 			      hb_printer_t<decltype (v)>().print (v), line);
312     if (plevel) --*plevel;
313     plevel = nullptr;
314     returned = true;
315     return hb_forward<T> (v);
316   }
317 
318   private:
319   unsigned int *plevel;
320   const char *what;
321   const void *obj;
322   bool returned;
323 };
324 template <typename ret_t> /* Make sure we don't use hb_auto_trace_t when not tracing. */
325 struct hb_auto_trace_t<0, ret_t>
326 {
hb_auto_trace_thb_auto_trace_t327   explicit inline hb_auto_trace_t (unsigned int *plevel_,
328 				   const char *what_,
329 				   const void *obj_,
330 				   const char *func,
331 				   const char *message,
332 				   ...) HB_PRINTF_FUNC(6, 7) {}
333 
334   template <typename T>
rethb_auto_trace_t335   T ret (T&& v,
336 	 const char *func HB_UNUSED = nullptr,
337 	 unsigned int line HB_UNUSED = 0) { return hb_forward<T> (v); }
338 };
339 
340 /* For disabled tracing; optimize out everything.
341  * https://github.com/harfbuzz/harfbuzz/pull/605 */
342 template <typename ret_t>
343 struct hb_no_trace_t {
344   template <typename T>
rethb_no_trace_t345   T ret (T&& v,
346 	 const char *func HB_UNUSED = nullptr,
347 	 unsigned int line HB_UNUSED = 0) { return hb_forward<T> (v); }
348 };
349 
350 #define return_trace(RET) return trace.ret (RET, HB_FUNC, __LINE__)
351 
352 
353 /*
354  * Instances.
355  */
356 
357 #ifndef HB_DEBUG_ARABIC
358 #define HB_DEBUG_ARABIC (HB_DEBUG+0)
359 #endif
360 
361 #ifndef HB_DEBUG_BLOB
362 #define HB_DEBUG_BLOB (HB_DEBUG+0)
363 #endif
364 
365 #ifndef HB_DEBUG_CORETEXT
366 #define HB_DEBUG_CORETEXT (HB_DEBUG+0)
367 #endif
368 
369 #ifndef HB_DEBUG_DIRECTWRITE
370 #define HB_DEBUG_DIRECTWRITE (HB_DEBUG+0)
371 #endif
372 
373 #ifndef HB_DEBUG_FT
374 #define HB_DEBUG_FT (HB_DEBUG+0)
375 #endif
376 
377 #ifndef HB_DEBUG_GET_COVERAGE
378 #define HB_DEBUG_GET_COVERAGE (HB_DEBUG+0)
379 #endif
380 
381 #ifndef HB_DEBUG_OBJECT
382 #define HB_DEBUG_OBJECT (HB_DEBUG+0)
383 #endif
384 
385 #ifndef HB_DEBUG_SHAPE_PLAN
386 #define HB_DEBUG_SHAPE_PLAN (HB_DEBUG+0)
387 #endif
388 
389 #ifndef HB_DEBUG_UNISCRIBE
390 #define HB_DEBUG_UNISCRIBE (HB_DEBUG+0)
391 #endif
392 
393 /*
394  * With tracing.
395  */
396 
397 #ifndef HB_DEBUG_APPLY
398 #define HB_DEBUG_APPLY (HB_DEBUG+0)
399 #endif
400 #if HB_DEBUG_APPLY
401 #define TRACE_APPLY(this) \
402 	hb_auto_trace_t<HB_DEBUG_APPLY, bool> trace \
403 	(&c->debug_depth, c->get_name (), this, HB_FUNC, \
404 	 "idx %d gid %u lookup %d", \
405 	 c->buffer->idx, c->buffer->cur().codepoint, (int) c->lookup_index)
406 #else
407 #define TRACE_APPLY(this) hb_no_trace_t<bool> trace
408 #endif
409 
410 #ifndef HB_DEBUG_SANITIZE
411 #define HB_DEBUG_SANITIZE (HB_DEBUG+0)
412 #endif
413 #if HB_DEBUG_SANITIZE
414 #define TRACE_SANITIZE(this) \
415 	hb_auto_trace_t<HB_DEBUG_SANITIZE, bool> trace \
416 	(&c->debug_depth, c->get_name (), this, HB_FUNC, \
417 	 " ")
418 #else
419 #define TRACE_SANITIZE(this) hb_no_trace_t<bool> trace
420 #endif
421 
422 #ifndef HB_DEBUG_SERIALIZE
423 #define HB_DEBUG_SERIALIZE (HB_DEBUG+0)
424 #endif
425 #if HB_DEBUG_SERIALIZE
426 #define TRACE_SERIALIZE(this) \
427 	hb_auto_trace_t<HB_DEBUG_SERIALIZE, bool> trace \
428 	(&c->debug_depth, "SERIALIZE", c, HB_FUNC, \
429 	 " ")
430 #else
431 #define TRACE_SERIALIZE(this) hb_no_trace_t<bool> trace
432 #endif
433 
434 #ifndef HB_DEBUG_SUBSET
435 #define HB_DEBUG_SUBSET (HB_DEBUG+0)
436 #endif
437 #if HB_DEBUG_SUBSET
438 #define TRACE_SUBSET(this) \
439   hb_auto_trace_t<HB_DEBUG_SUBSET, bool> trace \
440   (&c->debug_depth, c->get_name (), this, HB_FUNC, \
441    " ")
442 #else
443 #define TRACE_SUBSET(this) hb_no_trace_t<bool> trace
444 #endif
445 
446 #ifndef HB_DEBUG_DISPATCH
447 #define HB_DEBUG_DISPATCH ( \
448 	HB_DEBUG_APPLY + \
449 	HB_DEBUG_SANITIZE + \
450 	HB_DEBUG_SERIALIZE + \
451 	HB_DEBUG_SUBSET + \
452 	0)
453 #endif
454 #if HB_DEBUG_DISPATCH
455 #define TRACE_DISPATCH(this, format) \
456 	hb_auto_trace_t<context_t::max_debug_depth, typename context_t::return_t> trace \
457 	(&c->debug_depth, c->get_name (), this, HB_FUNC, \
458 	 "format %d", (int) format)
459 #else
460 #define TRACE_DISPATCH(this, format) hb_no_trace_t<typename context_t::return_t> trace
461 #endif
462 
463 
464 #endif /* HB_DEBUG_HH */
465