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 };
50 
51 union hb_options_union_t {
52   int i;
53   hb_options_t opts;
54 };
55 static_assert ((sizeof (hb_atomic_int_t) >= sizeof (hb_options_union_t)), "");
56 
57 HB_INTERNAL void
58 _hb_options_init ();
59 
60 extern HB_INTERNAL hb_atomic_int_t _hb_options;
61 
62 static inline hb_options_t
hb_options()63 hb_options ()
64 {
65 #ifdef HB_NO_GETENV
66   return hb_options_t ();
67 #endif
68   /* Make a local copy, so we can access bitfield threadsafely. */
69   hb_options_union_t u;
70   u.i = _hb_options.get_relaxed ();
71 
72   if (unlikely (!u.i))
73   {
74     _hb_options_init ();
75     u.i = _hb_options.get_relaxed ();
76   }
77 
78   return u.opts;
79 }
80 
81 
82 /*
83  * Debug output (needs enabling at compile time.)
84  */
85 
86 static inline bool
_hb_debug(unsigned int level,unsigned int max_level)87 _hb_debug (unsigned int level,
88 	   unsigned int max_level)
89 {
90   return level < max_level;
91 }
92 
93 #define DEBUG_LEVEL_ENABLED(WHAT, LEVEL) (_hb_debug ((LEVEL), HB_DEBUG_##WHAT))
94 #define DEBUG_ENABLED(WHAT) (DEBUG_LEVEL_ENABLED (WHAT, 0))
95 
96 static inline void
_hb_print_func(const char * func)97 _hb_print_func (const char *func)
98 {
99   if (func)
100   {
101     unsigned int func_len = strlen (func);
102     /* Skip "static" */
103     if (0 == strncmp (func, "static ", 7))
104       func += 7;
105     /* Skip "typename" */
106     if (0 == strncmp (func, "typename ", 9))
107       func += 9;
108     /* Skip return type */
109     const char *space = strchr (func, ' ');
110     if (space)
111       func = space + 1;
112     /* Skip parameter list */
113     const char *paren = strchr (func, '(');
114     if (paren)
115       func_len = paren - func;
116     fprintf (stderr, "%.*s", func_len, func);
117   }
118 }
119 
120 template <int max_level> static inline void
121 _hb_debug_msg_va (const char *what,
122 		  const void *obj,
123 		  const char *func,
124 		  bool indented,
125 		  unsigned int level,
126 		  int level_dir,
127 		  const char *message,
128 		  va_list ap) HB_PRINTF_FUNC(7, 0);
129 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)130 _hb_debug_msg_va (const char *what,
131 		  const void *obj,
132 		  const char *func,
133 		  bool indented,
134 		  unsigned int level,
135 		  int level_dir,
136 		  const char *message,
137 		  va_list ap)
138 {
139   if (!_hb_debug (level, max_level))
140     return;
141 
142   fprintf (stderr, "%-10s", what ? what : "");
143 
144   if (obj)
145     fprintf (stderr, "(%*p) ", (unsigned int) (2 * sizeof (void *)), obj);
146   else
147     fprintf (stderr, " %*s  ", (unsigned int) (2 * sizeof (void *)), "");
148 
149   if (indented) {
150 #define VBAR	"\342\224\202"	/* U+2502 BOX DRAWINGS LIGHT VERTICAL */
151 #define VRBAR	"\342\224\234"	/* U+251C BOX DRAWINGS LIGHT VERTICAL AND RIGHT */
152 #define DLBAR	"\342\225\256"	/* U+256E BOX DRAWINGS LIGHT ARC DOWN AND LEFT */
153 #define ULBAR	"\342\225\257"	/* U+256F BOX DRAWINGS LIGHT ARC UP AND LEFT */
154 #define LBAR	"\342\225\264"	/* U+2574 BOX DRAWINGS LIGHT LEFT */
155     static const char bars[] =
156       VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR
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     fprintf (stderr, "%2u %s" VRBAR "%s",
162 	     level,
163 	     bars + sizeof (bars) - 1 - hb_min ((unsigned int) sizeof (bars) - 1, (unsigned int) (sizeof (VBAR) - 1) * level),
164 	     level_dir ? (level_dir > 0 ? DLBAR : ULBAR) : LBAR);
165   } else
166     fprintf (stderr, "   " VRBAR LBAR);
167 
168   _hb_print_func (func);
169 
170   if (message)
171   {
172     fprintf (stderr, ": ");
173     vfprintf (stderr, message, ap);
174   }
175 
176   fprintf (stderr, "\n");
177 }
178 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)179 _hb_debug_msg_va<0> (const char *what HB_UNUSED,
180 		     const void *obj HB_UNUSED,
181 		     const char *func HB_UNUSED,
182 		     bool indented HB_UNUSED,
183 		     unsigned int level HB_UNUSED,
184 		     int level_dir HB_UNUSED,
185 		     const char *message HB_UNUSED,
186 		     va_list ap HB_UNUSED) {}
187 
188 template <int max_level> static inline void
189 _hb_debug_msg (const char *what,
190 	       const void *obj,
191 	       const char *func,
192 	       bool indented,
193 	       unsigned int level,
194 	       int level_dir,
195 	       const char *message,
196 	       ...) HB_PRINTF_FUNC(7, 8);
197 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,...)198 _hb_debug_msg (const char *what,
199 	       const void *obj,
200 	       const char *func,
201 	       bool indented,
202 	       unsigned int level,
203 	       int level_dir,
204 	       const char *message,
205 	       ...)
206 {
207   va_list ap;
208   va_start (ap, message);
209   _hb_debug_msg_va<max_level> (what, obj, func, indented, level, level_dir, message, ap);
210   va_end (ap);
211 }
212 template <> inline void
213 _hb_debug_msg<0> (const char *what HB_UNUSED,
214 		  const void *obj HB_UNUSED,
215 		  const char *func HB_UNUSED,
216 		  bool indented HB_UNUSED,
217 		  unsigned int level HB_UNUSED,
218 		  int level_dir HB_UNUSED,
219 		  const char *message HB_UNUSED,
220 		  ...) HB_PRINTF_FUNC(7, 8);
221 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,...)222 _hb_debug_msg<0> (const char *what HB_UNUSED,
223 		  const void *obj HB_UNUSED,
224 		  const char *func HB_UNUSED,
225 		  bool indented HB_UNUSED,
226 		  unsigned int level HB_UNUSED,
227 		  int level_dir HB_UNUSED,
228 		  const char *message HB_UNUSED,
229 		  ...) {}
230 
231 #define DEBUG_MSG_LEVEL(WHAT, OBJ, LEVEL, LEVEL_DIR, ...)	_hb_debug_msg<HB_DEBUG_##WHAT> (#WHAT, (OBJ), nullptr,    true, (LEVEL), (LEVEL_DIR), __VA_ARGS__)
232 #define DEBUG_MSG(WHAT, OBJ, ...)				_hb_debug_msg<HB_DEBUG_##WHAT> (#WHAT, (OBJ), nullptr,    false, 0, 0, __VA_ARGS__)
233 #define DEBUG_MSG_FUNC(WHAT, OBJ, ...)				_hb_debug_msg<HB_DEBUG_##WHAT> (#WHAT, (OBJ), HB_FUNC, false, 0, 0, __VA_ARGS__)
234 
235 
236 /*
237  * Printer
238  */
239 
240 template <typename T>
241 struct hb_printer_t {
printhb_printer_t242   const char *print (const T&) { return "something"; }
243 };
244 
245 template <>
246 struct hb_printer_t<bool> {
printhb_printer_t247   const char *print (bool v) { return v ? "true" : "false"; }
248 };
249 
250 template <>
251 struct hb_printer_t<hb_empty_t> {
printhb_printer_t252   const char *print (hb_empty_t) { return ""; }
253 };
254 
255 
256 /*
257  * Trace
258  */
259 
260 template <typename T>
_hb_warn_no_return(bool returned)261 static inline void _hb_warn_no_return (bool returned)
262 {
263   if (unlikely (!returned)) {
264     fprintf (stderr, "OUCH, returned with no call to return_trace().  This is a bug, please report.\n");
265   }
266 }
267 template <>
_hb_warn_no_return(bool returned HB_UNUSED)268 /*static*/ inline void _hb_warn_no_return<hb_empty_t> (bool returned HB_UNUSED)
269 {}
270 
271 template <int max_level, typename ret_t>
272 struct hb_auto_trace_t
273 {
hb_auto_trace_thb_auto_trace_t274   explicit inline hb_auto_trace_t (unsigned int *plevel_,
275 				   const char *what_,
276 				   const void *obj_,
277 				   const char *func,
278 				   const char *message,
279 				   ...) HB_PRINTF_FUNC(6, 7)
280 				   : plevel (plevel_), what (what_), obj (obj_), returned (false)
281   {
282     if (plevel) ++*plevel;
283 
284     va_list ap;
285     va_start (ap, message);
286     _hb_debug_msg_va<max_level> (what, obj, func, true, plevel ? *plevel : 0, +1, message, ap);
287     va_end (ap);
288   }
~hb_auto_trace_thb_auto_trace_t289   ~hb_auto_trace_t ()
290   {
291     _hb_warn_no_return<ret_t> (returned);
292     if (!returned) {
293       _hb_debug_msg<max_level> (what, obj, nullptr, true, plevel ? *plevel : 1, -1, " ");
294     }
295     if (plevel) --*plevel;
296   }
297 
298   template <typename T>
rethb_auto_trace_t299   T ret (T&& v,
300 	 const char *func = "",
301 	 unsigned int line = 0)
302   {
303     if (unlikely (returned)) {
304       fprintf (stderr, "OUCH, double calls to return_trace().  This is a bug, please report.\n");
305       return hb_forward<T> (v);
306     }
307 
308     _hb_debug_msg<max_level> (what, obj, func, true, plevel ? *plevel : 1, -1,
309 			      "return %s (line %d)",
310 			      hb_printer_t<decltype (v)>().print (v), line);
311     if (plevel) --*plevel;
312     plevel = nullptr;
313     returned = true;
314     return hb_forward<T> (v);
315   }
316 
317   private:
318   unsigned int *plevel;
319   const char *what;
320   const void *obj;
321   bool returned;
322 };
323 template <typename ret_t> /* Make sure we don't use hb_auto_trace_t when not tracing. */
324 struct hb_auto_trace_t<0, ret_t>
325 {
hb_auto_trace_thb_auto_trace_t326   explicit inline hb_auto_trace_t (unsigned int *plevel_,
327 				   const char *what_,
328 				   const void *obj_,
329 				   const char *func,
330 				   const char *message,
331 				   ...) HB_PRINTF_FUNC(6, 7) {}
332 
333   template <typename T>
rethb_auto_trace_t334   T ret (T&& v,
335 	 const char *func HB_UNUSED = nullptr,
336 	 unsigned int line HB_UNUSED = 0) { return hb_forward<T> (v); }
337 };
338 
339 /* For disabled tracing; optimize out everything.
340  * https://github.com/harfbuzz/harfbuzz/pull/605 */
341 template <typename ret_t>
342 struct hb_no_trace_t {
343   template <typename T>
rethb_no_trace_t344   T ret (T&& v,
345 	 const char *func HB_UNUSED = nullptr,
346 	 unsigned int line HB_UNUSED = 0) { return hb_forward<T> (v); }
347 };
348 
349 #define return_trace(RET) return trace.ret (RET, HB_FUNC, __LINE__)
350 
351 
352 /*
353  * Instances.
354  */
355 
356 #ifndef HB_DEBUG_ARABIC
357 #define HB_DEBUG_ARABIC (HB_DEBUG+0)
358 #endif
359 
360 #ifndef HB_DEBUG_BLOB
361 #define HB_DEBUG_BLOB (HB_DEBUG+0)
362 #endif
363 
364 #ifndef HB_DEBUG_CORETEXT
365 #define HB_DEBUG_CORETEXT (HB_DEBUG+0)
366 #endif
367 
368 #ifndef HB_DEBUG_DIRECTWRITE
369 #define HB_DEBUG_DIRECTWRITE (HB_DEBUG+0)
370 #endif
371 
372 #ifndef HB_DEBUG_FT
373 #define HB_DEBUG_FT (HB_DEBUG+0)
374 #endif
375 
376 #ifndef HB_DEBUG_OBJECT
377 #define HB_DEBUG_OBJECT (HB_DEBUG+0)
378 #endif
379 
380 #ifndef HB_DEBUG_SHAPE_PLAN
381 #define HB_DEBUG_SHAPE_PLAN (HB_DEBUG+0)
382 #endif
383 
384 #ifndef HB_DEBUG_UNISCRIBE
385 #define HB_DEBUG_UNISCRIBE (HB_DEBUG+0)
386 #endif
387 
388 /*
389  * With tracing.
390  */
391 
392 #ifndef HB_DEBUG_APPLY
393 #define HB_DEBUG_APPLY (HB_DEBUG+0)
394 #endif
395 #if HB_DEBUG_APPLY
396 #define TRACE_APPLY(this) \
397 	hb_auto_trace_t<HB_DEBUG_APPLY, bool> trace \
398 	(&c->debug_depth, c->get_name (), this, HB_FUNC, \
399 	 "idx %d gid %u lookup %d", \
400 	 c->buffer->idx, c->buffer->cur().codepoint, (int) c->lookup_index)
401 #else
402 #define TRACE_APPLY(this) hb_no_trace_t<bool> trace
403 #endif
404 
405 #ifndef HB_DEBUG_SANITIZE
406 #define HB_DEBUG_SANITIZE (HB_DEBUG+0)
407 #endif
408 #if HB_DEBUG_SANITIZE
409 #define TRACE_SANITIZE(this) \
410 	hb_auto_trace_t<HB_DEBUG_SANITIZE, bool> trace \
411 	(&c->debug_depth, c->get_name (), this, HB_FUNC, \
412 	 " ")
413 #else
414 #define TRACE_SANITIZE(this) hb_no_trace_t<bool> trace
415 #endif
416 
417 #ifndef HB_DEBUG_SERIALIZE
418 #define HB_DEBUG_SERIALIZE (HB_DEBUG+0)
419 #endif
420 #if HB_DEBUG_SERIALIZE
421 #define TRACE_SERIALIZE(this) \
422 	hb_auto_trace_t<HB_DEBUG_SERIALIZE, bool> trace \
423 	(&c->debug_depth, "SERIALIZE", c, HB_FUNC, \
424 	 " ")
425 #else
426 #define TRACE_SERIALIZE(this) hb_no_trace_t<bool> trace
427 #endif
428 
429 #ifndef HB_DEBUG_SUBSET
430 #define HB_DEBUG_SUBSET (HB_DEBUG+0)
431 #endif
432 #if HB_DEBUG_SUBSET
433 #define TRACE_SUBSET(this) \
434   hb_auto_trace_t<HB_DEBUG_SUBSET, bool> trace \
435   (&c->debug_depth, c->get_name (), this, HB_FUNC, \
436    " ")
437 #else
438 #define TRACE_SUBSET(this) hb_no_trace_t<bool> trace
439 #endif
440 
441 #ifndef HB_DEBUG_SUBSET_REPACK
442 #define HB_DEBUG_SUBSET_REPACK (HB_DEBUG+0)
443 #endif
444 
445 #ifndef HB_DEBUG_DISPATCH
446 #define HB_DEBUG_DISPATCH ( \
447 	HB_DEBUG_APPLY + \
448 	HB_DEBUG_SANITIZE + \
449 	HB_DEBUG_SERIALIZE + \
450 	HB_DEBUG_SUBSET + \
451 	0)
452 #endif
453 #if HB_DEBUG_DISPATCH
454 #define TRACE_DISPATCH(this, format) \
455 	hb_auto_trace_t<context_t::max_debug_depth, typename context_t::return_t> trace \
456 	(&c->debug_depth, c->get_name (), this, HB_FUNC, \
457 	 "format %d", (int) format)
458 #else
459 #define TRACE_DISPATCH(this, format) hb_no_trace_t<typename context_t::return_t> trace
460 #endif
461 
462 
463 #endif /* HB_DEBUG_HH */
464