dhcpd-pools  2.28
ISC dhcpd lease usage analyser
streq.h
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1 /* Optimized string comparison.
2  Copyright (C) 2001-2002, 2007, 2009-2015 Free Software Foundation, Inc.
3 
4  This program is free software: you can redistribute it and/or modify it
5  under the terms of the GNU General Public License as published
6  by the Free Software Foundation; either version 3 of the License, or
7  (at your option) any later version.
8 
9  This program is distributed in the hope that it will be useful,
10  but WITHOUT ANY WARRANTY; without even the implied warranty of
11  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  General Public License for more details.
13 
14  You should have received a copy of the GNU General Public License
15  along with this program. If not, see <http://www.gnu.org/licenses/>. */
16 
17 /* Written by Bruno Haible <bruno@clisp.org>. */
18 
19 #ifndef _GL_STREQ_H
20 #define _GL_STREQ_H
21 
22 #include <string.h>
23 
24 /* STREQ_OPT allows to optimize string comparison with a small literal string.
25  STREQ_OPT (s, "EUC-KR", 'E', 'U', 'C', '-', 'K', 'R', 0, 0, 0)
26  is semantically equivalent to
27  strcmp (s, "EUC-KR") == 0
28  just faster. */
29 
30 /* Help GCC to generate good code for string comparisons with
31  immediate strings. */
32 #if defined (__GNUC__) && defined (__OPTIMIZE__)
33 
34 static inline int
35 streq9 (const char *s1, const char *s2)
36 {
37  return strcmp (s1 + 9, s2 + 9) == 0;
38 }
39 
40 static inline int
41 streq8 (const char *s1, const char *s2, char s28)
42 {
43  if (s1[8] == s28)
44  {
45  if (s28 == 0)
46  return 1;
47  else
48  return streq9 (s1, s2);
49  }
50  else
51  return 0;
52 }
53 
54 static inline int
55 streq7 (const char *s1, const char *s2, char s27, char s28)
56 {
57  if (s1[7] == s27)
58  {
59  if (s27 == 0)
60  return 1;
61  else
62  return streq8 (s1, s2, s28);
63  }
64  else
65  return 0;
66 }
67 
68 static inline int
69 streq6 (const char *s1, const char *s2, char s26, char s27, char s28)
70 {
71  if (s1[6] == s26)
72  {
73  if (s26 == 0)
74  return 1;
75  else
76  return streq7 (s1, s2, s27, s28);
77  }
78  else
79  return 0;
80 }
81 
82 static inline int
83 streq5 (const char *s1, const char *s2, char s25, char s26, char s27, char s28)
84 {
85  if (s1[5] == s25)
86  {
87  if (s25 == 0)
88  return 1;
89  else
90  return streq6 (s1, s2, s26, s27, s28);
91  }
92  else
93  return 0;
94 }
95 
96 static inline int
97 streq4 (const char *s1, const char *s2, char s24, char s25, char s26, char s27, char s28)
98 {
99  if (s1[4] == s24)
100  {
101  if (s24 == 0)
102  return 1;
103  else
104  return streq5 (s1, s2, s25, s26, s27, s28);
105  }
106  else
107  return 0;
108 }
109 
110 static inline int
111 streq3 (const char *s1, const char *s2, char s23, char s24, char s25, char s26, char s27, char s28)
112 {
113  if (s1[3] == s23)
114  {
115  if (s23 == 0)
116  return 1;
117  else
118  return streq4 (s1, s2, s24, s25, s26, s27, s28);
119  }
120  else
121  return 0;
122 }
123 
124 static inline int
125 streq2 (const char *s1, const char *s2, char s22, char s23, char s24, char s25, char s26, char s27, char s28)
126 {
127  if (s1[2] == s22)
128  {
129  if (s22 == 0)
130  return 1;
131  else
132  return streq3 (s1, s2, s23, s24, s25, s26, s27, s28);
133  }
134  else
135  return 0;
136 }
137 
138 static inline int
139 streq1 (const char *s1, const char *s2, char s21, char s22, char s23, char s24, char s25, char s26, char s27, char s28)
140 {
141  if (s1[1] == s21)
142  {
143  if (s21 == 0)
144  return 1;
145  else
146  return streq2 (s1, s2, s22, s23, s24, s25, s26, s27, s28);
147  }
148  else
149  return 0;
150 }
151 
152 static inline int
153 streq0 (const char *s1, const char *s2, char s20, char s21, char s22, char s23, char s24, char s25, char s26, char s27, char s28)
154 {
155  if (s1[0] == s20)
156  {
157  if (s20 == 0)
158  return 1;
159  else
160  return streq1 (s1, s2, s21, s22, s23, s24, s25, s26, s27, s28);
161  }
162  else
163  return 0;
164 }
165 
166 #define STREQ_OPT(s1,s2,s20,s21,s22,s23,s24,s25,s26,s27,s28) \
167  streq0 (s1, s2, s20, s21, s22, s23, s24, s25, s26, s27, s28)
168 
169 #else
170 
171 #define STREQ_OPT(s1,s2,s20,s21,s22,s23,s24,s25,s26,s27,s28) \
172  (strcmp (s1, s2) == 0)
173 
174 #endif
175 
176 #endif /* _GL_STREQ_H */