hb-private.hh revision 5f9569c1391c65d7addff363ad6e5ec9b087f01a
1/*
2 * Copyright © 2007,2008,2009  Red Hat, Inc.
3 * Copyright © 2011,2012  Google, Inc.
4 *
5 *  This is part of HarfBuzz, a text shaping library.
6 *
7 * Permission is hereby granted, without written agreement and without
8 * license or royalty fees, to use, copy, modify, and distribute this
9 * software and its documentation for any purpose, provided that the
10 * above copyright notice and the following two paragraphs appear in
11 * all copies of this software.
12 *
13 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
14 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
15 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
16 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
17 * DAMAGE.
18 *
19 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
20 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
21 * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
22 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
23 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
24 *
25 * Red Hat Author(s): Behdad Esfahbod
26 * Google Author(s): Behdad Esfahbod
27 */
28
29#ifndef HB_PRIVATE_HH
30#define HB_PRIVATE_HH
31
32#ifdef HAVE_CONFIG_H
33#include "config.h"
34#endif
35
36#include "hb.h"
37#define HB_H_IN
38#ifdef HAVE_OT
39#include "hb-ot.h"
40#define HB_OT_H_IN
41#endif
42
43#include <stdlib.h>
44#include <stddef.h>
45#include <string.h>
46#include <assert.h>
47
48/* We only use these two for debug output.  However, the debug code is
49 * always seen by the compiler (and optimized out in non-debug builds.
50 * If including these becomes a problem, we can start thinking about
51 * someway around that. */
52#include <stdio.h>
53#include <errno.h>
54#include <stdarg.h>
55
56
57
58/* Essentials */
59
60#ifndef NULL
61# define NULL ((void *) 0)
62#endif
63
64
65/* Void! */
66struct _hb_void_t {};
67typedef const _hb_void_t &hb_void_t;
68#define HB_VOID (* (const _hb_void_t *) NULL)
69
70
71/* Basics */
72
73
74#undef MIN
75template <typename Type>
76static inline Type MIN (const Type &a, const Type &b) { return a < b ? a : b; }
77
78#undef MAX
79template <typename Type>
80static inline Type MAX (const Type &a, const Type &b) { return a > b ? a : b; }
81
82
83#undef  ARRAY_LENGTH
84template <typename Type, unsigned int n>
85static inline unsigned int ARRAY_LENGTH (const Type (&)[n]) { return n; }
86/* A const version, but does not detect erratically being called on pointers. */
87#define ARRAY_LENGTH_CONST(__array) ((signed int) (sizeof (__array) / sizeof (__array[0])))
88
89#define HB_STMT_START do
90#define HB_STMT_END   while (0)
91
92#define _ASSERT_STATIC1(_line, _cond)	typedef int _static_assert_on_line_##_line##_failed[(_cond)?1:-1]
93#define _ASSERT_STATIC0(_line, _cond)	_ASSERT_STATIC1 (_line, (_cond))
94#define ASSERT_STATIC(_cond)		_ASSERT_STATIC0 (__LINE__, (_cond))
95
96#define ASSERT_STATIC_EXPR(_cond)((void) sizeof (char[(_cond) ? 1 : -1]))
97#define ASSERT_STATIC_EXPR_ZERO(_cond) (0 * sizeof (char[(_cond) ? 1 : -1]))
98
99#define _PASTE1(a,b) a##b
100#define PASTE(a,b) _PASTE1(a,b)
101
102/* Lets assert int types.  Saves trouble down the road. */
103
104ASSERT_STATIC (sizeof (int8_t) == 1);
105ASSERT_STATIC (sizeof (uint8_t) == 1);
106ASSERT_STATIC (sizeof (int16_t) == 2);
107ASSERT_STATIC (sizeof (uint16_t) == 2);
108ASSERT_STATIC (sizeof (int32_t) == 4);
109ASSERT_STATIC (sizeof (uint32_t) == 4);
110ASSERT_STATIC (sizeof (int64_t) == 8);
111ASSERT_STATIC (sizeof (uint64_t) == 8);
112
113ASSERT_STATIC (sizeof (hb_codepoint_t) == 4);
114ASSERT_STATIC (sizeof (hb_position_t) == 4);
115ASSERT_STATIC (sizeof (hb_mask_t) == 4);
116ASSERT_STATIC (sizeof (hb_var_int_t) == 4);
117
118
119/* We like our types POD */
120
121#define _ASSERT_TYPE_POD1(_line, _type)	union _type_##_type##_on_line_##_line##_is_not_POD { _type instance; }
122#define _ASSERT_TYPE_POD0(_line, _type)	_ASSERT_TYPE_POD1 (_line, _type)
123#define ASSERT_TYPE_POD(_type)		_ASSERT_TYPE_POD0 (__LINE__, _type)
124
125#ifdef __GNUC__
126# define _ASSERT_INSTANCE_POD1(_line, _instance) \
127	HB_STMT_START { \
128		typedef __typeof__(_instance) _type_##_line; \
129		_ASSERT_TYPE_POD1 (_line, _type_##_line); \
130	} HB_STMT_END
131#else
132# define _ASSERT_INSTANCE_POD1(_line, _instance)	typedef int _assertion_on_line_##_line##_not_tested
133#endif
134# define _ASSERT_INSTANCE_POD0(_line, _instance)	_ASSERT_INSTANCE_POD1 (_line, _instance)
135# define ASSERT_INSTANCE_POD(_instance)			_ASSERT_INSTANCE_POD0 (__LINE__, _instance)
136
137/* Check _assertion in a method environment */
138#define _ASSERT_POD1(_line) \
139	inline void _static_assertion_on_line_##_line (void) const \
140	{ _ASSERT_INSTANCE_POD1 (_line, *this); /* Make sure it's POD. */ }
141# define _ASSERT_POD0(_line)	_ASSERT_POD1 (_line)
142# define ASSERT_POD()		_ASSERT_POD0 (__LINE__)
143
144
145
146/* Misc */
147
148
149#if defined(__GNUC__) && (__GNUC__ > 2) && defined(__OPTIMIZE__)
150#define _HB_BOOLEAN_EXPR(expr) ((expr) ? 1 : 0)
151#define likely(expr) (__builtin_expect (_HB_BOOLEAN_EXPR(expr), 1))
152#define unlikely(expr) (__builtin_expect (_HB_BOOLEAN_EXPR(expr), 0))
153#else
154#define likely(expr) (expr)
155#define unlikely(expr) (expr)
156#endif
157
158#ifndef __GNUC__
159#undef __attribute__
160#define __attribute__(x)
161#endif
162
163#if __GNUC__ >= 3
164#define HB_PURE_FUNC	__attribute__((pure))
165#define HB_CONST_FUNC	__attribute__((const))
166#define HB_PRINTF_FUNC(format_idx, arg_idx) __attribute__((__format__ (__printf__, format_idx, arg_idx)))
167#else
168#define HB_PURE_FUNC
169#define HB_CONST_FUNC
170#define HB_PRINTF_FUNC(format_idx, arg_idx)
171#endif
172#if __GNUC__ >= 4
173#define HB_UNUSED	__attribute__((unused))
174#else
175#define HB_UNUSED
176#endif
177
178#ifndef HB_INTERNAL
179# ifndef __MINGW32__
180#  define HB_INTERNAL __attribute__((__visibility__("hidden")))
181# else
182#  define HB_INTERNAL
183# endif
184#endif
185
186
187#if (defined(__WIN32__) && !defined(__WINE__)) || defined(_MSC_VER)
188#define snprintf _snprintf
189#endif
190
191#ifdef _MSC_VER
192#undef inline
193#define inline __inline
194#endif
195
196#ifdef __STRICT_ANSI__
197#undef inline
198#define inline __inline__
199#endif
200
201
202#if __GNUC__ >= 3
203#define HB_FUNC __PRETTY_FUNCTION__
204#elif defined(_MSC_VER)
205#define HB_FUNC __FUNCSIG__
206#else
207#define HB_FUNC __func__
208#endif
209
210
211/* Return the number of 1 bits in mask. */
212static inline HB_CONST_FUNC unsigned int
213_hb_popcount32 (uint32_t mask)
214{
215#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4)
216  return __builtin_popcount (mask);
217#else
218  /* "HACKMEM 169" */
219  register uint32_t y;
220  y = (mask >> 1) &033333333333;
221  y = mask - y - ((y >>1) & 033333333333);
222  return (((y + (y >> 3)) & 030707070707) % 077);
223#endif
224}
225
226/* Returns the number of bits needed to store number */
227static inline HB_CONST_FUNC unsigned int
228_hb_bit_storage (unsigned int number)
229{
230#if defined(__GNUC__) && (__GNUC__ >= 4) && defined(__OPTIMIZE__)
231  return likely (number) ? (sizeof (unsigned int) * 8 - __builtin_clz (number)) : 0;
232#else
233  register unsigned int n_bits = 0;
234  while (number) {
235    n_bits++;
236    number >>= 1;
237  }
238  return n_bits;
239#endif
240}
241
242/* Returns the number of zero bits in the least significant side of number */
243static inline HB_CONST_FUNC unsigned int
244_hb_ctz (unsigned int number)
245{
246#if defined(__GNUC__) && (__GNUC__ >= 4) && defined(__OPTIMIZE__)
247  return likely (number) ? __builtin_ctz (number) : 0;
248#else
249  register unsigned int n_bits = 0;
250  if (unlikely (!number)) return 0;
251  while (!(number & 1)) {
252    n_bits++;
253    number >>= 1;
254  }
255  return n_bits;
256#endif
257}
258
259static inline bool
260_hb_unsigned_int_mul_overflows (unsigned int count, unsigned int size)
261{
262  return (size > 0) && (count >= ((unsigned int) -1) / size);
263}
264
265
266/* Type of bsearch() / qsort() compare function */
267typedef int (*hb_compare_func_t) (const void *, const void *);
268
269
270
271
272/* arrays and maps */
273
274
275#define HB_PREALLOCED_ARRAY_INIT {0}
276template <typename Type, unsigned int StaticSize>
277struct hb_prealloced_array_t
278{
279  unsigned int len;
280  unsigned int allocated;
281  Type *array;
282  Type static_array[StaticSize];
283
284  void init (void) { memset (this, 0, sizeof (*this)); }
285
286  inline Type& operator [] (unsigned int i) { return array[i]; }
287  inline const Type& operator [] (unsigned int i) const { return array[i]; }
288
289  inline Type *push (void)
290  {
291    if (!array) {
292      array = static_array;
293      allocated = ARRAY_LENGTH (static_array);
294    }
295    if (likely (len < allocated))
296      return &array[len++];
297
298    /* Need to reallocate */
299    unsigned int new_allocated = allocated + (allocated >> 1) + 8;
300    Type *new_array = NULL;
301
302    if (array == static_array) {
303      new_array = (Type *) calloc (new_allocated, sizeof (Type));
304      if (new_array)
305        memcpy (new_array, array, len * sizeof (Type));
306    } else {
307      bool overflows = (new_allocated < allocated) || _hb_unsigned_int_mul_overflows (new_allocated, sizeof (Type));
308      if (likely (!overflows)) {
309	new_array = (Type *) realloc (array, new_allocated * sizeof (Type));
310      }
311    }
312
313    if (unlikely (!new_array))
314      return NULL;
315
316    array = new_array;
317    allocated = new_allocated;
318    return &array[len++];
319  }
320
321  inline void pop (void)
322  {
323    len--;
324    /* TODO: shrink array if needed */
325  }
326
327  inline void shrink (unsigned int l)
328  {
329     if (l < len)
330       len = l;
331    /* TODO: shrink array if needed */
332  }
333
334  template <typename T>
335  inline Type *find (T v) {
336    for (unsigned int i = 0; i < len; i++)
337      if (array[i] == v)
338	return &array[i];
339    return NULL;
340  }
341  template <typename T>
342  inline const Type *find (T v) const {
343    for (unsigned int i = 0; i < len; i++)
344      if (array[i] == v)
345	return &array[i];
346    return NULL;
347  }
348
349  inline void sort (void)
350  {
351    qsort (array, len, sizeof (Type), (hb_compare_func_t) Type::cmp);
352  }
353
354  inline void sort (unsigned int start, unsigned int end)
355  {
356    qsort (array + start, end - start, sizeof (Type), (hb_compare_func_t) Type::cmp);
357  }
358
359  template <typename T>
360  inline Type *bsearch (T *key)
361  {
362    return (Type *) ::bsearch (key, array, len, sizeof (Type), (hb_compare_func_t) Type::cmp);
363  }
364  template <typename T>
365  inline const Type *bsearch (T *key) const
366  {
367    return (const Type *) ::bsearch (key, array, len, sizeof (Type), (hb_compare_func_t) Type::cmp);
368  }
369
370  inline void finish (void)
371  {
372    if (array != static_array)
373      free (array);
374    array = NULL;
375    allocated = len = 0;
376  }
377};
378
379
380#define HB_LOCKABLE_SET_INIT {HB_PREALLOCED_ARRAY_INIT}
381template <typename item_t, typename lock_t>
382struct hb_lockable_set_t
383{
384  hb_prealloced_array_t <item_t, 2> items;
385
386  inline void init (void) { items.init (); }
387
388  template <typename T>
389  inline item_t *replace_or_insert (T v, lock_t &l, bool replace)
390  {
391    l.lock ();
392    item_t *item = items.find (v);
393    if (item) {
394      if (replace) {
395	item_t old = *item;
396	*item = v;
397	l.unlock ();
398	old.finish ();
399      }
400      else {
401        item = NULL;
402	l.unlock ();
403      }
404    } else {
405      item = items.push ();
406      if (likely (item))
407	*item = v;
408      l.unlock ();
409    }
410    return item;
411  }
412
413  template <typename T>
414  inline void remove (T v, lock_t &l)
415  {
416    l.lock ();
417    item_t *item = items.find (v);
418    if (item) {
419      item_t old = *item;
420      *item = items[items.len - 1];
421      items.pop ();
422      l.unlock ();
423      old.finish ();
424    } else {
425      l.unlock ();
426    }
427  }
428
429  template <typename T>
430  inline bool find (T v, item_t *i, lock_t &l)
431  {
432    l.lock ();
433    item_t *item = items.find (v);
434    if (item)
435      *i = *item;
436    l.unlock ();
437    return !!item;
438  }
439
440  template <typename T>
441  inline item_t *find_or_insert (T v, lock_t &l)
442  {
443    l.lock ();
444    item_t *item = items.find (v);
445    if (!item) {
446      item = items.push ();
447      if (likely (item))
448        *item = v;
449    }
450    l.unlock ();
451    return item;
452  }
453
454  inline void finish (lock_t &l)
455  {
456    if (!items.len) {
457      /* No need for locking. */
458      items.finish ();
459      return;
460    }
461    l.lock ();
462    while (items.len) {
463      item_t old = items[items.len - 1];
464	items.pop ();
465	l.unlock ();
466	old.finish ();
467	l.lock ();
468    }
469    items.finish ();
470    l.unlock ();
471  }
472
473};
474
475
476
477
478/* Big-endian handling */
479
480static inline uint16_t hb_be_uint16 (const uint16_t v)
481{
482  const uint8_t *V = (const uint8_t *) &v;
483  return (V[0] << 8) | V[1];
484}
485
486static inline uint16_t hb_uint16_swap (const uint16_t v)
487{
488  return (v >> 8) | (v << 8);
489}
490
491static inline uint32_t hb_uint32_swap (const uint32_t v)
492{
493  return (hb_uint16_swap (v) << 16) | hb_uint16_swap (v >> 16);
494}
495
496/* Note, of the following macros, uint16_get is the one called many many times.
497 * If there is any optimizations to be done, it's in that macro.  However, I
498 * already confirmed that on my T400 ThinkPad at least, using bswap_16(), which
499 * results in a single ror instruction, does NOT speed this up.  In fact, it
500 * resulted in a minor slowdown.  At any rate, note that v may not be correctly
501 * aligned, so I think the current implementation is optimal.
502 */
503
504#define hb_be_uint16_put(v,V)	HB_STMT_START { v[0] = (V>>8); v[1] = (V); } HB_STMT_END
505#define hb_be_uint16_get(v)	(uint16_t) ((v[0] << 8) + v[1])
506#define hb_be_uint16_eq(a,b)	(a[0] == b[0] && a[1] == b[1])
507
508#define hb_be_uint32_put(v,V)	HB_STMT_START { v[0] = (V>>24); v[1] = (V>>16); v[2] = (V>>8); v[3] = (V); } HB_STMT_END
509#define hb_be_uint32_get(v)	(uint32_t) ((v[0] << 24) + (v[1] << 16) + (v[2] << 8) + v[3])
510#define hb_be_uint32_eq(a,b)	(a[0] == b[0] && a[1] == b[1] && a[2] == b[2] && a[3] == b[3])
511
512
513/* ASCII tag/character handling */
514
515static inline unsigned char ISALPHA (unsigned char c)
516{ return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z'); }
517static inline unsigned char ISALNUM (unsigned char c)
518{ return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9'); }
519static inline unsigned char TOUPPER (unsigned char c)
520{ return (c >= 'a' && c <= 'z') ? c - 'a' + 'A' : c; }
521static inline unsigned char TOLOWER (unsigned char c)
522{ return (c >= 'A' && c <= 'Z') ? c - 'A' + 'a' : c; }
523
524#define HB_TAG_CHAR4(s)   (HB_TAG(((const char *) s)[0], \
525				  ((const char *) s)[1], \
526				  ((const char *) s)[2], \
527				  ((const char *) s)[3]))
528
529
530/* C++ helpers */
531
532/* Makes class uncopyable.  Use in private: section. */
533#define NO_COPY(T) \
534  T (const T &o); \
535  T &operator = (const T &o)
536
537
538/* Debug */
539
540
541#ifndef HB_DEBUG
542#define HB_DEBUG 0
543#endif
544
545static inline bool
546_hb_debug (unsigned int level,
547	   unsigned int max_level)
548{
549  return level < max_level;
550}
551
552#define DEBUG_LEVEL(WHAT, LEVEL) (_hb_debug ((LEVEL), HB_DEBUG_##WHAT))
553#define DEBUG(WHAT) (DEBUG_LEVEL (WHAT, 0))
554
555template <int max_level> static inline void
556_hb_debug_msg_va (const char *what,
557		  const void *obj,
558		  const char *func,
559		  bool indented,
560		  unsigned int level,
561		  int level_dir,
562		  const char *message,
563		  va_list ap)
564{
565  if (!_hb_debug (level, max_level))
566    return;
567
568  fprintf (stderr, "%-10s", what ? what : "");
569
570  if (obj)
571    fprintf (stderr, "(%0*lx) ", (unsigned int) (2 * sizeof (void *)), (unsigned long) obj);
572  else
573    fprintf (stderr, " %*s  ", (unsigned int) (2 * sizeof (void *)), "");
574
575  if (indented) {
576/* One may want to add ASCII version of these.  See:
577 * https://bugs.freedesktop.org/show_bug.cgi?id=50970 */
578#define VBAR	"\342\224\202"	/* U+2502 BOX DRAWINGS LIGHT VERTICAL */
579#define VRBAR	"\342\224\234"	/* U+251C BOX DRAWINGS LIGHT VERTICAL AND RIGHT */
580#define DLBAR	"\342\225\256"	/* U+256E BOX DRAWINGS LIGHT ARC DOWN AND LEFT */
581#define ULBAR	"\342\225\257"	/* U+256F BOX DRAWINGS LIGHT ARC UP AND LEFT */
582#define LBAR	"\342\225\264"	/* U+2574 BOX DRAWINGS LIGHT LEFT */
583    static const char bars[] = VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR VBAR;
584    fprintf (stderr, "%2d %s" VRBAR "%s",
585	     level,
586	     bars + sizeof (bars) - 1 - MIN ((unsigned int) sizeof (bars), (unsigned int) (sizeof (VBAR) - 1) * level),
587	     level_dir ? (level_dir > 0 ? DLBAR : ULBAR) : LBAR);
588  } else
589    fprintf (stderr, "   " VRBAR LBAR);
590
591  if (func)
592  {
593    /* Skip "typename" */
594    if (0 == strncmp (func, "typename ", 9))
595      func += 9;
596    /* Skip return type */
597    const char *space = strchr (func, ' ');
598    if (space)
599      func = space + 1;
600    /* Skip parameter list */
601    const char *paren = strchr (func, '(');
602    unsigned int func_len = paren ? paren - func : strlen (func);
603    fprintf (stderr, "%.*s: ", func_len, func);
604  }
605
606  if (message)
607    vfprintf (stderr, message, ap);
608
609  fprintf (stderr, "\n");
610}
611template <> inline void
612_hb_debug_msg_va<0> (const char *what HB_UNUSED,
613		     const void *obj HB_UNUSED,
614		     const char *func HB_UNUSED,
615		     bool indented HB_UNUSED,
616		     unsigned int level HB_UNUSED,
617		     int level_dir HB_UNUSED,
618		     const char *message HB_UNUSED,
619		     va_list ap HB_UNUSED) {}
620
621template <int max_level> static inline void
622_hb_debug_msg (const char *what,
623	       const void *obj,
624	       const char *func,
625	       bool indented,
626	       unsigned int level,
627	       int level_dir,
628	       const char *message,
629	       ...) HB_PRINTF_FUNC(7, 8);
630template <int max_level> static inline void
631_hb_debug_msg (const char *what,
632	       const void *obj,
633	       const char *func,
634	       bool indented,
635	       unsigned int level,
636	       int level_dir,
637	       const char *message,
638	       ...)
639{
640  va_list ap;
641  va_start (ap, message);
642  _hb_debug_msg_va<max_level> (what, obj, func, indented, level, level_dir, message, ap);
643  va_end (ap);
644}
645template <> inline void
646_hb_debug_msg<0> (const char *what HB_UNUSED,
647		  const void *obj HB_UNUSED,
648		  const char *func HB_UNUSED,
649		  bool indented HB_UNUSED,
650		  unsigned int level HB_UNUSED,
651		  int level_dir HB_UNUSED,
652		  const char *message HB_UNUSED,
653		  ...) HB_PRINTF_FUNC(7, 8);
654template <> inline void
655_hb_debug_msg<0> (const char *what HB_UNUSED,
656		  const void *obj HB_UNUSED,
657		  const char *func HB_UNUSED,
658		  bool indented HB_UNUSED,
659		  unsigned int level HB_UNUSED,
660		  int level_dir HB_UNUSED,
661		  const char *message HB_UNUSED,
662		  ...) {}
663
664#define DEBUG_MSG_LEVEL(WHAT, OBJ, LEVEL, LEVEL_DIR, ...)	_hb_debug_msg<HB_DEBUG_##WHAT> (#WHAT, (OBJ), NULL,    true, (LEVEL), (LEVEL_DIR), __VA_ARGS__)
665#define DEBUG_MSG(WHAT, OBJ, ...) 				_hb_debug_msg<HB_DEBUG_##WHAT> (#WHAT, (OBJ), NULL,    false, 0, 0, __VA_ARGS__)
666#define DEBUG_MSG_FUNC(WHAT, OBJ, ...)				_hb_debug_msg<HB_DEBUG_##WHAT> (#WHAT, (OBJ), HB_FUNC, false, 0, 0, __VA_ARGS__)
667
668
669/*
670 * Printer
671 */
672
673template <typename T>
674struct hb_printer_t {};
675
676template <>
677struct hb_printer_t<bool> {
678  const char *print (bool v) { return v ? "true" : "false"; }
679};
680
681template <>
682struct hb_printer_t<hb_void_t> {
683  const char *print (hb_void_t) { return ""; }
684};
685
686
687/*
688 * Trace
689 */
690
691template <typename T>
692static inline void _hb_warn_no_return (bool returned)
693{
694  if (unlikely (!returned)) {
695    fprintf (stderr, "OUCH, returned with no call to TRACE_RETURN.  This is a bug, please report.\n");
696  }
697}
698template <>
699inline void _hb_warn_no_return<hb_void_t> (bool returned HB_UNUSED)
700{}
701
702template <int max_level, typename ret_t>
703struct hb_auto_trace_t {
704  explicit inline hb_auto_trace_t (unsigned int *plevel_,
705				   const char *what_,
706				   const void *obj_,
707				   const char *func,
708				   const char *message,
709				   ...) : plevel (plevel_), what (what_), obj (obj_), returned (false)
710  {
711    if (plevel) ++*plevel;
712
713    va_list ap;
714    va_start (ap, message);
715    _hb_debug_msg_va<max_level> (what, obj, func, true, plevel ? *plevel : 0, +1, message, ap);
716    va_end (ap);
717  }
718  inline ~hb_auto_trace_t (void)
719  {
720    _hb_warn_no_return<ret_t> (returned);
721    if (!returned) {
722      _hb_debug_msg<max_level> (what, obj, NULL, true, plevel ? *plevel : 1, -1, " ");
723    }
724    if (plevel) --*plevel;
725  }
726
727  inline ret_t ret (ret_t v, unsigned int line = 0)
728  {
729    if (unlikely (returned)) {
730      fprintf (stderr, "OUCH, double calls to TRACE_RETURN.  This is a bug, please report.\n");
731      return v;
732    }
733
734    _hb_debug_msg<max_level> (what, obj, NULL, true, plevel ? *plevel : 1, -1,
735			      "return %s (line %d)",
736			      hb_printer_t<ret_t>().print (v), line);
737    if (plevel) --*plevel;
738    plevel = NULL;
739    returned = true;
740    return v;
741  }
742
743  private:
744  unsigned int *plevel;
745  const char *what;
746  const void *obj;
747  bool returned;
748};
749template <typename ret_t> /* Optimize when tracing is disabled */
750struct hb_auto_trace_t<0, ret_t> {
751  explicit inline hb_auto_trace_t (unsigned int *plevel_ HB_UNUSED,
752				   const char *what HB_UNUSED,
753				   const void *obj HB_UNUSED,
754				   const char *func HB_UNUSED,
755				   const char *message HB_UNUSED,
756				   ...) {}
757
758  inline ret_t ret (ret_t v, unsigned int line HB_UNUSED = 0) { return v; }
759};
760
761#define TRACE_RETURN(RET) trace.ret (RET, __LINE__)
762
763/* Misc */
764
765
766/* Pre-mature optimization:
767 * Checks for lo <= u <= hi but with an optimization if lo and hi
768 * are only different in a contiguous set of lower-most bits.
769 */
770template <typename T> static inline bool
771hb_in_range (T u, T lo, T hi)
772{
773  if ( ((lo^hi) & lo) == 0 &&
774       ((lo^hi) & hi) == (lo^hi) &&
775       ((lo^hi) & ((lo^hi) + 1)) == 0 )
776    return (u & ~(lo^hi)) == lo;
777  else
778    return lo <= u && u <= hi;
779}
780
781template <typename T> static inline bool
782hb_in_ranges (T u, T lo1, T hi1, T lo2, T hi2, T lo3, T hi3)
783{
784  return hb_in_range (u, lo1, hi1) || hb_in_range (u, lo2, hi2) || hb_in_range (u, lo3, hi3);
785}
786
787
788/* Useful for set-operations on small enums.
789 * For example, for testing "x ∈ {x1, x2, x3}" use:
790 * (FLAG(x) & (FLAG(x1) | FLAG(x2) | FLAG(x3)))
791 */
792#define FLAG(x) (1<<(x))
793#define FLAG_RANGE(x,y) (ASSERT_STATIC_EXPR_ZERO ((x) < (y)) + FLAG(y+1) - FLAG(x))
794
795
796template <typename T, typename T2> inline void
797hb_bubble_sort (T *array, unsigned int len, int(*compar)(const T *, const T *), T2 *array2)
798{
799  if (unlikely (!len))
800    return;
801
802  unsigned int k = len - 1;
803  do {
804    unsigned int new_k = 0;
805
806    for (unsigned int j = 0; j < k; j++)
807      if (compar (&array[j], &array[j+1]) > 0)
808      {
809        {
810	  T t;
811	  t = array[j];
812	  array[j] = array[j + 1];
813	  array[j + 1] = t;
814	}
815        if (array2)
816        {
817	  T2 t;
818	  t = array2[j];
819	  array2[j] = array2[j + 1];
820	  array2[j + 1] = t;
821	}
822
823	new_k = j;
824      }
825    k = new_k;
826  } while (k);
827}
828
829template <typename T> inline void
830hb_bubble_sort (T *array, unsigned int len, int(*compar)(const T *, const T *))
831{
832  hb_bubble_sort (array, len, compar, (int *) NULL);
833}
834
835static inline hb_bool_t
836hb_codepoint_parse (const char *s, unsigned int len, int base, hb_codepoint_t *out)
837{
838  /* Pain because we don't know whether s is nul-terminated. */
839  char buf[64];
840  strncpy (buf, s, MIN (ARRAY_LENGTH (buf) - 1, len));
841  buf[MIN (ARRAY_LENGTH (buf) - 1, len)] = '\0';
842
843  char *end;
844  errno = 0;
845  unsigned long v = strtoul (buf, &end, base);
846  if (errno) return false;
847  if (*end) return false;
848  *out = v;
849  return true;
850}
851
852
853#endif /* HB_PRIVATE_HH */
854