1 /*************************************************
2 * Perl-Compatible Regular Expressions *
3 *************************************************/
4
5 /* PCRE is a library of functions to support regular expressions whose syntax
6 and semantics are as close as possible to those of the Perl 5 language.
7
8 Written by Philip Hazel
9 Original API code Copyright (c) 1997-2012 University of Cambridge
10 New API code Copyright (c) 2018-2021 University of Cambridge
11
12 -----------------------------------------------------------------------------
13 Redistribution and use in source and binary forms, with or without
14 modification, are permitted provided that the following conditions are met:
15
16 * Redistributions of source code must retain the above copyright notice,
17 this list of conditions and the following disclaimer.
18
19 * Redistributions in binary form must reproduce the above copyright
20 notice, this list of conditions and the following disclaimer in the
21 documentation and/or other materials provided with the distribution.
22
23 * Neither the name of the University of Cambridge nor the names of its
24 contributors may be used to endorse or promote products derived from
25 this software without specific prior written permission.
26
27 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
28 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
31 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 POSSIBILITY OF SUCH DAMAGE.
38 -----------------------------------------------------------------------------
39 */
40
41 /* This module contains internal functions for comparing and finding the length
42 of strings. These are used instead of strcmp() etc because the standard
43 functions work only on 8-bit data. */
44
45
46 #ifdef HAVE_CONFIG_H
47 #include "config.h"
48 #endif
49
50 #include "pcre2_internal.h"
51
52
53 /*************************************************
54 * Emulated memmove() for systems without it *
55 *************************************************/
56
57 /* This function can make use of bcopy() if it is available. Otherwise do it by
58 steam, as there some non-Unix environments that lack both memmove() and
59 bcopy(). */
60
61 #if !defined(VPCOMPAT) && !defined(HAVE_MEMMOVE)
62 void *
PRIV(memmove)63 PRIV(memmove)(void *d, const void *s, size_t n)
64 {
65 #ifdef HAVE_BCOPY
66 bcopy(s, d, n);
67 return d;
68 #else
69 size_t i;
70 unsigned char *dest = (unsigned char *)d;
71 const unsigned char *src = (const unsigned char *)s;
72 if (dest > src)
73 {
74 dest += n;
75 src += n;
76 for (i = 0; i < n; ++i) *(--dest) = *(--src);
77 return (void *)dest;
78 }
79 else
80 {
81 for (i = 0; i < n; ++i) *dest++ = *src++;
82 return (void *)(dest - n);
83 }
84 #endif /* not HAVE_BCOPY */
85 }
86 #endif /* not VPCOMPAT && not HAVE_MEMMOVE */
87
88
89 /*************************************************
90 * Compare two zero-terminated PCRE2 strings *
91 *************************************************/
92
93 /*
94 Arguments:
95 str1 first string
96 str2 second string
97
98 Returns: 0, 1, or -1
99 */
100
101 int
PRIV(strcmp)102 PRIV(strcmp)(PCRE2_SPTR str1, PCRE2_SPTR str2)
103 {
104 PCRE2_UCHAR c1, c2;
105 while (*str1 != '\0' || *str2 != '\0')
106 {
107 c1 = *str1++;
108 c2 = *str2++;
109 if (c1 != c2) return ((c1 > c2) << 1) - 1;
110 }
111 return 0;
112 }
113
114
115 /*************************************************
116 * Compare zero-terminated PCRE2 & 8-bit strings *
117 *************************************************/
118
119 /* As the 8-bit string is almost always a literal, its type is specified as
120 const char *.
121
122 Arguments:
123 str1 first string
124 str2 second string
125
126 Returns: 0, 1, or -1
127 */
128
129 int
PRIV(strcmp_c8)130 PRIV(strcmp_c8)(PCRE2_SPTR str1, const char *str2)
131 {
132 PCRE2_UCHAR c1, c2;
133 while (*str1 != '\0' || *str2 != '\0')
134 {
135 c1 = *str1++;
136 c2 = *str2++;
137 if (c1 != c2) return ((c1 > c2) << 1) - 1;
138 }
139 return 0;
140 }
141
142
143 /*************************************************
144 * Compare two PCRE2 strings, given a length *
145 *************************************************/
146
147 /*
148 Arguments:
149 str1 first string
150 str2 second string
151 len the length
152
153 Returns: 0, 1, or -1
154 */
155
156 int
PRIV(strncmp)157 PRIV(strncmp)(PCRE2_SPTR str1, PCRE2_SPTR str2, size_t len)
158 {
159 PCRE2_UCHAR c1, c2;
160 for (; len > 0; len--)
161 {
162 c1 = *str1++;
163 c2 = *str2++;
164 if (c1 != c2) return ((c1 > c2) << 1) - 1;
165 }
166 return 0;
167 }
168
169
170 /*************************************************
171 * Compare PCRE2 string to 8-bit string by length *
172 *************************************************/
173
174 /* As the 8-bit string is almost always a literal, its type is specified as
175 const char *.
176
177 Arguments:
178 str1 first string
179 str2 second string
180 len the length
181
182 Returns: 0, 1, or -1
183 */
184
185 int
PRIV(strncmp_c8)186 PRIV(strncmp_c8)(PCRE2_SPTR str1, const char *str2, size_t len)
187 {
188 PCRE2_UCHAR c1, c2;
189 for (; len > 0; len--)
190 {
191 c1 = *str1++;
192 c2 = *str2++;
193 if (c1 != c2) return ((c1 > c2) << 1) - 1;
194 }
195 return 0;
196 }
197
198
199 /*************************************************
200 * Find the length of a PCRE2 string *
201 *************************************************/
202
203 /*
204 Argument: the string
205 Returns: the length
206 */
207
208 PCRE2_SIZE
PRIV(strlen)209 PRIV(strlen)(PCRE2_SPTR str)
210 {
211 PCRE2_SIZE c = 0;
212 while (*str++ != 0) c++;
213 return c;
214 }
215
216
217 /*************************************************
218 * Copy 8-bit 0-terminated string to PCRE2 string *
219 *************************************************/
220
221 /* Arguments:
222 str1 buffer to receive the string
223 str2 8-bit string to be copied
224
225 Returns: the number of code units used (excluding trailing zero)
226 */
227
228 PCRE2_SIZE
PRIV(strcpy_c8)229 PRIV(strcpy_c8)(PCRE2_UCHAR *str1, const char *str2)
230 {
231 PCRE2_UCHAR *t = str1;
232 while (*str2 != 0) *t++ = *str2++;
233 *t = 0;
234 return t - str1;
235 }
236
237 /* End of pcre2_string_utils.c */
238
