about summary refs log tree commit diff
path: root/string/bits/string2.h
blob: e39d4f1a85c25a4f47418e6a5613b27177ca6cbb (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
/* Machine-independant string function optimizations.
   Copyright (C) 1997-2016 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <http://www.gnu.org/licenses/>.  */

#ifndef _STRING_H
# error "Never use <bits/string2.h> directly; include <string.h> instead."
#endif

#ifndef __NO_STRING_INLINES

/* Unlike the definitions in the header <bits/string.h> the
   definitions contained here are not optimized down to assembler
   level.  Those optimizations are not always a good idea since this
   means the code size increases a lot.  Instead the definitions here
   optimize some functions in a way which do not dramatically
   increase the code size and which do not use assembler.  The main
   trick is to use GCC's `__builtin_constant_p' function.

   Every function XXX which has a defined version in
   <bits/string.h> must be accompanied by a symbol _HAVE_STRING_ARCH_XXX
   to make sure we don't get redefinitions.

   We must use here macros instead of inline functions since the
   trick won't work with the latter.  */

#ifndef __STRING_INLINE
# ifdef __cplusplus
#  define __STRING_INLINE inline
# else
#  define __STRING_INLINE __extern_inline
# endif
#endif

/* Dereferencing a pointer arg to run sizeof on it fails for the void
   pointer case, so we use this instead.
   Note that __x is evaluated twice. */
#define __string2_1bptr_p(__x) \
  ((size_t)(const void *)((__x) + 1) - (size_t)(const void *)(__x) == 1)

/* Set N bytes of S to 0.  */
#if !defined _HAVE_STRING_ARCH_memset
# define __bzero(s, n) __builtin_memset (s, '\0', n)
#endif


#ifndef _HAVE_STRING_ARCH_strchr
extern void *__rawmemchr (const void *__s, int __c);
#  define strchr(s, c) \
  (__extension__ (__builtin_constant_p (c) && !__builtin_constant_p (s)	      \
		  && (c) == '\0'					      \
		  ? (char *) __rawmemchr (s, c)				      \
		  : __builtin_strchr (s, c)))
#endif


/* Copy SRC to DEST, returning pointer to final NUL byte.  */
#ifdef __USE_GNU
# ifndef _HAVE_STRING_ARCH_stpcpy
#  define __stpcpy(dest, src) __builtin_stpcpy (dest, src)
/* In glibc we use this function frequently but for namespace reasons
   we have to use the name `__stpcpy'.  */
#  define stpcpy(dest, src) __stpcpy (dest, src)
# endif
#endif


/* Copy no more than N characters of SRC to DEST.  */
#ifndef _HAVE_STRING_ARCH_strncpy
# define strncpy(dest, src, n) __builtin_strncpy (dest, src, n)
#endif


/* Append no more than N characters from SRC onto DEST.  */
#ifndef _HAVE_STRING_ARCH_strncat
# ifdef _USE_STRING_ARCH_strchr
#  define strncat(dest, src, n) \
  (__extension__ ({ char *__dest = (dest);				      \
		    __builtin_constant_p (src) && __builtin_constant_p (n)    \
		    ? (strlen (src) < ((size_t) (n))			      \
		       ? strcat (__dest, src)				      \
		       : (*((char *) __mempcpy (strchr (__dest, '\0'),	      \
						src, n)) = '\0', __dest))     \
		    : strncat (dest, src, n); }))
# else
#  define strncat(dest, src, n) __builtin_strncat (dest, src, n)
# endif
#endif


/* Compare characters of S1 and S2.  */
#ifndef _HAVE_STRING_ARCH_strcmp
# define strcmp(s1, s2) \
  __extension__								      \
  ({ size_t __s1_len, __s2_len;						      \
     (__builtin_constant_p (s1) && __builtin_constant_p (s2)		      \
      && (__s1_len = strlen (s1), __s2_len = strlen (s2),		      \
	  (!__string2_1bptr_p (s1) || __s1_len >= 4)			      \
	  && (!__string2_1bptr_p (s2) || __s2_len >= 4))		      \
      ? __builtin_strcmp (s1, s2)					      \
      : (__builtin_constant_p (s1) && __string2_1bptr_p (s1)		      \
	 && (__s1_len = strlen (s1), __s1_len < 4)			      \
	 ? (__builtin_constant_p (s2) && __string2_1bptr_p (s2)		      \
	    ? __builtin_strcmp (s1, s2)					      \
	    : __strcmp_cg (s1, s2, __s1_len))				      \
	 : (__builtin_constant_p (s2) && __string2_1bptr_p (s2)		      \
	    && (__s2_len = strlen (s2), __s2_len < 4)			      \
	    ? (__builtin_constant_p (s1) && __string2_1bptr_p (s1)	      \
	       ? __builtin_strcmp (s1, s2)				      \
	       : -__strcmp_cg (s2, s1, __s2_len))			      \
            : __builtin_strcmp (s1, s2)))); })

# define __strcmp_cg(s1, s2, l1) \
  (__extension__ ({ const unsigned char *__s2 =				      \
		      (const unsigned char *) (const char *) (s2);	      \
		    int __result =					      \
		      (((const unsigned char *) (const char *) (s1))[0]	      \
		       - __s2[0]);					      \
		    if (l1 > 0 && __result == 0)			      \
		      {							      \
			__result = (((const unsigned char *)		      \
				     (const char *) (s1))[1] - __s2[1]);      \
			if (l1 > 1 && __result == 0)			      \
			  {						      \
			    __result = (((const unsigned char *)	      \
					 (const char *) (s1))[2] - __s2[2]);  \
			    if (l1 > 2 && __result == 0)		      \
			      __result = (((const unsigned char *)	      \
					  (const char *)  (s1))[3]	      \
					  - __s2[3]);			      \
			  }						      \
		      }							      \
		    __result; }))
#endif


/* Compare N characters of S1 and S2.  */
#ifndef _HAVE_STRING_ARCH_strncmp
# define strncmp(s1, s2, n)						      \
  (__extension__ (__builtin_constant_p (n)				      \
		  && ((__builtin_constant_p (s1)			      \
		       && strlen (s1) < ((size_t) (n)))			      \
		      || (__builtin_constant_p (s2)			      \
			  && strlen (s2) < ((size_t) (n))))		      \
		  ? strcmp (s1, s2) : strncmp (s1, s2, n)))
#endif


/* Return the length of the initial segment of S which
   consists entirely of characters not in REJECT.  */
#ifndef _HAVE_STRING_ARCH_strcspn
# define strcspn(s, reject) __builtin_strcspn (s, reject)
#endif


/* Return the length of the initial segment of S which
   consists entirely of characters in ACCEPT.  */
#ifndef _HAVE_STRING_ARCH_strspn
# define strspn(s, accept) __builtin_strspn (s, accept)
#endif


/* Find the first occurrence in S of any character in ACCEPT.  */
#ifndef _HAVE_STRING_ARCH_strpbrk
# define strpbrk(s, accept) __builtin_strpbrk (s, accept)
#endif


#if !defined _HAVE_STRING_ARCH_strsep || defined _FORCE_INLINES
# ifndef _HAVE_STRING_ARCH_strsep

extern char *__strsep_g (char **__stringp, const char *__delim);
#  define __strsep(s, reject) \
  __extension__								      \
  ({ char __r0, __r1, __r2;						      \
     (__builtin_constant_p (reject) && __string2_1bptr_p (reject)	      \
      && (__r0 = ((const char *) (reject))[0],				      \
	  ((const char *) (reject))[0] != '\0')				      \
      ? ((__r1 = ((const char *) (reject))[1],				      \
	 ((const char *) (reject))[1] == '\0')				      \
	 ? __strsep_1c (s, __r0)					      \
	 : ((__r2 = ((const char *) (reject))[2], __r2 == '\0')		      \
	    ? __strsep_2c (s, __r0, __r1)				      \
	    : (((const char *) (reject))[3] == '\0'			      \
	       ? __strsep_3c (s, __r0, __r1, __r2)			      \
	       : __strsep_g (s, reject))))				      \
      : __strsep_g (s, reject)); })
# endif

__STRING_INLINE char *__strsep_1c (char **__s, char __reject);
__STRING_INLINE char *
__strsep_1c (char **__s, char __reject)
{
  char *__retval = *__s;
  if (__retval != NULL && (*__s = strchr (__retval, __reject)) != NULL)
    *(*__s)++ = '\0';
  return __retval;
}

__STRING_INLINE char *__strsep_2c (char **__s, char __reject1, char __reject2);
__STRING_INLINE char *
__strsep_2c (char **__s, char __reject1, char __reject2)
{
  char *__retval = *__s;
  if (__retval != NULL)
    {
      char *__cp = __retval;
      while (1)
	{
	  if (*__cp == '\0')
	    {
	      __cp = NULL;
	  break;
	    }
	  if (*__cp == __reject1 || *__cp == __reject2)
	    {
	      *__cp++ = '\0';
	      break;
	    }
	  ++__cp;
	}
      *__s = __cp;
    }
  return __retval;
}

__STRING_INLINE char *__strsep_3c (char **__s, char __reject1, char __reject2,
				   char __reject3);
__STRING_INLINE char *
__strsep_3c (char **__s, char __reject1, char __reject2, char __reject3)
{
  char *__retval = *__s;
  if (__retval != NULL)
    {
      char *__cp = __retval;
      while (1)
	{
	  if (*__cp == '\0')
	    {
	      __cp = NULL;
	  break;
	    }
	  if (*__cp == __reject1 || *__cp == __reject2 || *__cp == __reject3)
	    {
	      *__cp++ = '\0';
	      break;
	    }
	  ++__cp;
	}
      *__s = __cp;
    }
  return __retval;
}
# ifdef __USE_MISC
#  define strsep(s, reject) __strsep (s, reject)
# endif
#endif

/* We need the memory allocation functions for inline strdup().
   Referring to stdlib.h (even minimally) is not allowed
   in any of the tight standards compliant modes.  */
#ifdef __USE_MISC

# if !defined _HAVE_STRING_ARCH_strdup || !defined _HAVE_STRING_ARCH_strndup
#  define __need_malloc_and_calloc
#  include <stdlib.h>
# endif

# ifndef _HAVE_STRING_ARCH_strdup

extern char *__strdup (const char *__string) __THROW __attribute_malloc__;
#  define __strdup(s) \
  (__extension__ (__builtin_constant_p (s) && __string2_1bptr_p (s)	      \
		  ? (((const char *) (s))[0] == '\0'			      \
		     ? (char *) calloc ((size_t) 1, (size_t) 1)		      \
		     : ({ size_t __len = strlen (s) + 1;		      \
			  char *__retval = (char *) malloc (__len);	      \
			  if (__retval != NULL)				      \
			    __retval = (char *) memcpy (__retval, s, __len);  \
			  __retval; }))					      \
		  : __strdup (s)))

#  if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
#   define strdup(s) __strdup (s)
#  endif
# endif

# ifndef _HAVE_STRING_ARCH_strndup

extern char *__strndup (const char *__string, size_t __n)
     __THROW __attribute_malloc__;
#  define __strndup(s, n) \
  (__extension__ (__builtin_constant_p (s) && __string2_1bptr_p (s)	      \
		  ? (((const char *) (s))[0] == '\0'			      \
		     ? (char *) calloc ((size_t) 1, (size_t) 1)		      \
		     : ({ size_t __len = strlen (s) + 1;		      \
			  size_t __n = (n);				      \
			  char *__retval;				      \
			  if (__n < __len)				      \
			    __len = __n + 1;				      \
			  __retval = (char *) malloc (__len);		      \
			  if (__retval != NULL)				      \
			    {						      \
			      __retval[__len - 1] = '\0';		      \
			      __retval = (char *) memcpy (__retval, s,	      \
							  __len - 1);	      \
			    }						      \
			  __retval; }))					      \
		  : __strndup (s, n)))

#  ifdef __USE_XOPEN2K8
#   define strndup(s, n) __strndup (s, n)
#  endif
# endif

#endif /* Use misc. or use GNU.  */

#ifndef _FORCE_INLINES
# undef __STRING_INLINE
#endif

#endif /* No string inlines.  */