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
|
/* Machine-independant string function optimizations.
Copyright (C) 1997 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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#ifndef _BITS_STRING2_H
#define _BITS_STRING2_H 1
/* Unlike the definitions in the header <bits/string.h> the
definitions contained here are not optimizing down to assembler
level. These 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 does not dramatically
increase the code size and which does not use assembler. The main
trick is to use GNU CC's `__builtin_constant_p' function.
Every function XXX which has a defined version in
<bits/string.h> must be accompanied by a have _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 later. */
#ifdef __cplusplus
# define __STRING_INLINE inline
#else
# define __STRING_INLINE extern __inline
#endif
/* We need some more types. */
#include <bits/types.h>
/* Copy SRC to DEST. */
#ifndef _HAVE_STRING_ARCH_strcpy
# define strcpy(dest, src) \
(__extension__ (__builtin_constant_p (src) \
? (strlen (src) + 1 <= 8 \
? __strcpy_small (dest, src, strlen (src) + 1) \
: (char *) memcpy (dest, src, strlen (src) + 1)) \
: strcpy (dest, src)))
__STRING_INLINE char *
__strcpy_small (char *__dest, __const char *__src, size_t __srclen)
{
register char *__tmp = __dest;
switch (__srclen)
{
case 7:
*((__uint16_t *) __tmp)++ = *((__uint16_t *) __src)++;
case 5:
*((__uint32_t *) __tmp)++ = *((__uint32_t *) __src)++;
*((unsigned char *) __tmp) = '\0';
break;
case 8:
*((__uint32_t *) __tmp)++ = *((__uint32_t *) __src)++;
case 4:
*((__uint32_t *) __tmp) = *((__uint32_t *) __src);
break;
case 6:
*((__uint32_t *) __tmp)++ = *((__uint32_t *) __src)++;
case 2:
*((__uint16_t *) __tmp) = *((__uint16_t *) __src);
break;
case 3:
*((__uint16_t *) __tmp)++ = *((__uint16_t *) __src)++;
case 1:
*((unsigned char *) __tmp) = '\0';
break;
default:
break;
}
return __dest;
}
#endif
/* Copy SRC to DEST, returning pointer to final NUL byte. */
#ifdef __USE_GNU
# ifndef _HAVE_STRING_ARCH_stpcpy
# define __stpcpy(dest, src) \
(__extension__ (__builtin_constant_p (src) \
? (strlen (src) + 1 <= 8 \
? __stpcpy_small (dest, src, strlen (src) + 1) \
: ((char *) __mempcpy (dest, src, strlen (src) + 1) - 1))\
: __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)
__STRING_INLINE char *
__stpcpy_small (char *__dest, __const char *__src, size_t __srclen)
{
register char *__tmp = __dest;
switch (__srclen)
{
case 7:
*((__uint16_t *) __tmp)++ = *((__uint16_t *) __src)++;
case 5:
*((__uint32_t *) __tmp)++ = *((__uint32_t *) __src)++;
*((unsigned char *) __tmp) = '\0';
return __tmp;
case 8:
*((__uint32_t *) __tmp)++ = *((__uint32_t *) __src)++;
case 4:
*((__uint32_t *) __tmp) = *((__uint32_t *) __src);
return __tmp + 3;
case 6:
*((__uint32_t *) __tmp)++ = *((__uint32_t *) __src)++;
case 2:
*((__uint16_t *) __tmp) = *((__uint16_t *) __src);
return __tmp + 1;
case 3:
*((__uint16_t *) __tmp)++ = *((__uint16_t *) __src)++;
case 1:
*((unsigned char *) __tmp) = '\0';
return __tmp;
default:
break;
}
/* This should never happen. */
return NULL;
}
# endif
#endif
/* Copy no more than N characters of SRC to DEST. */
#ifndef _HAVE_STRING_ARCH_strncpy
# if defined _HAVE_STRING_ARCH_memset && defined _HAVE_STRING_ARCH_mempcpy
# define strncpy(dest, src, n) \
(__extension__ (__builtin_constant_p (src) && __builtin_constant_p (n) \
? (strlen (src) + 1 >= ((size_t) (n)) \
? (char *) memcpy (dest, src, n) \
: (memset (__mempcpy (dest, src, strlen (src)), '\0', \
n - strlen (src)), \
dest)) \
: strncpy (dest, src, n)))
# else
# define strncpy(dest, src, n) \
(__extension__ (__builtin_constant_p (src) && __builtin_constant_p (n) \
? (strlen (src) + 1 >= ((size_t) (n)) \
? (char *) memcpy (dest, src, n) \
: strncpy (dest, src, n)) \
: strncpy (dest, src, n)))
# endif
#endif
/* Append no more than N characters from SRC onto DEST. */
#ifndef _HAVE_STRING_ARCH_strncat
# ifdef _HAVE_STRING_ARCH_strchr
# define strncat(dest, src, n) \
(__extension__ (__builtin_constant_p (src) && __builtin_constant_p (n) \
? (strlen (src) < ((size_t) (n)) \
? strcat (dest, src) \
: (memcpy (strchr (dest, '\0'), src, n), dest)) \
: strncat (dest, src, n)))
# else
# define strncat(dest, src, n) \
(__extension__ (__builtin_constant_p (src) && __builtin_constant_p (n) \
? (strlen (src) < ((size_t) (n)) \
? strcat (dest, src) \
: strncat (dest, src, n)) \
: strncat (dest, src, n)))
# endif
#endif
/* Compare N characters of S1 and S2. */
#ifndef _HAVE_STRING_ARCH_strncmp
# define strncmp(s1, s2, n) \
(__extension__ (__builtin_constant_p (s1) && strlen (s1) < ((size_t) (n)) \
? strcmp (s1, s2) \
: (__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) \
(__extension__ (__builtin_constant_p (reject) \
? (((const char *) (reject))[0] == '\0' \
? strlen (s) \
: (((const char *) (reject))[1] == '\0' \
? __strcspn_c1 (s, ((((const char *) (reject))[0] \
& 0xff) << 8)) \
: strcspn (s, reject))) \
: strcspn (s, reject)))
__STRING_INLINE size_t
__strcspn_c1 (__const char *__s, char __reject)
{
register size_t __result = 0;
while (__s[__result] != '\0' && __s[__result] != __reject)
++__result;
return __result;
}
#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) \
(__extension__ (__builtin_constant_p (accept) \
? (((const char *) (accept))[0] == '\0' \
? 0 \
: (((const char *) (accept))[1] == '\0' \
? __strspn_c1 (s, ((const char *) (accept))[0]) \
: strspn (s, accept))) \
: strspn (s, accept)))
__STRING_INLINE size_t
__strspn_c1 (__const char *__s, char __accept)
{
register size_t __result = 0;
/* Please note that __accept never can be '\0'. */
while (__s[__result] == __accept)
++__result;
return __result;
}
#endif
/* Find the first occurrence in S of any character in ACCEPT. */
#ifndef _HAVE_STRING_ARCH_strpbrk
# define strpbrk(s, accept) \
(__extension__ (__builtin_constant_p (accept) \
? (((const char *) (accept))[0] == '\0' \
? NULL \
: (((const char *) (accept))[1] == '\0' \
? strchr (s, ((const char *) (accept))[0]) \
: strpbrk (s, accept))) \
: strpbrk (s, accept)))
#endif
/* Find the first occurrence of NEEDLE in HAYSTACK. */
#ifndef _HAVE_STRING_ARCH_strstr
# define strstr(haystack, needle) \
(__extension__ (__builtin_constant_p (needle) \
? (((const char *) (needle))[0] == '\0' \
? haystack \
: (((const char *) (needle))[1] == '\0' \
? strchr (haystack, ((const char *) (needle))[0]) \
: strstr (haystack, needle))) \
: strstr (haystack, needle)))
#endif
#ifdef __USE_GNU
# ifndef _HAVE_STRING_ARCH_strnlen
extern __inline size_t
strnlen (__const char *__string, size_t __maxlen)
{
__const char *__end = (__const char *) memchr (__string, '\0', __maxlen);
return __end ? __end - __string : __maxlen;
}
# endif
#endif
#undef __STRING_INLINE
#endif /* bits/string2.h */
|
