1 /* File name comparison routine.
2
3 Copyright (C) 2007-2023 Free Software Foundation, Inc.
4
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2, or (at your option)
8 any later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software Foundation,
17 Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
18
19 #ifdef HAVE_CONFIG_H
20 #include "config.h"
21 #endif
22
23 #ifdef HAVE_STRING_H
24 #include <string.h>
25 #endif
26
27 #ifdef HAVE_STDLIB_H
28 #include <stdlib.h>
29 #endif
30
31 #include "filenames.h"
32 #include "safe-ctype.h"
33 #include "libiberty.h"
34
35 /*
36
37 @deftypefn Extension int filename_cmp (const char *@var{s1}, const char *@var{s2})
38
39 Return zero if the two file names @var{s1} and @var{s2} are equivalent.
40 If not equivalent, the returned value is similar to what @code{strcmp}
41 would return. In other words, it returns a negative value if @var{s1}
42 is less than @var{s2}, or a positive value if @var{s2} is greater than
43 @var{s2}.
44
45 This function does not normalize file names. As a result, this function
46 will treat filenames that are spelled differently as different even in
47 the case when the two filenames point to the same underlying file.
48 However, it does handle the fact that on DOS-like file systems, forward
49 and backward slashes are equal.
50
51 @end deftypefn
52
53 */
54
55 int
56 filename_cmp (const char *s1, const char *s2)
57 {
58 #if !defined(HAVE_DOS_BASED_FILE_SYSTEM) \
59 && !defined(HAVE_CASE_INSENSITIVE_FILE_SYSTEM)
60 return strcmp(s1, s2);
61 #else
62 for (;;)
63 {
64 int c1 = *s1;
65 int c2 = *s2;
66
67 #if defined (HAVE_CASE_INSENSITIVE_FILE_SYSTEM)
68 c1 = TOLOWER (c1);
69 c2 = TOLOWER (c2);
70 #endif
71
72 #if defined (HAVE_DOS_BASED_FILE_SYSTEM)
73 /* On DOS-based file systems, the '/' and the '\' are equivalent. */
74 if (c1 == '/')
75 c1 = '\\';
76 if (c2 == '/')
77 c2 = '\\';
78 #endif
79
80 if (c1 != c2)
81 return (c1 - c2);
82
83 if (c1 == '\0')
84 return 0;
85
86 s1++;
87 s2++;
88 }
89 #endif
90 }
91
92 /*
93
94 @deftypefn Extension int filename_ncmp (const char *@var{s1}, const char *@var{s2}, size_t @var{n})
95
96 Return zero if the two file names @var{s1} and @var{s2} are equivalent
97 in range @var{n}.
98 If not equivalent, the returned value is similar to what @code{strncmp}
99 would return. In other words, it returns a negative value if @var{s1}
100 is less than @var{s2}, or a positive value if @var{s2} is greater than
101 @var{s2}.
102
103 This function does not normalize file names. As a result, this function
104 will treat filenames that are spelled differently as different even in
105 the case when the two filenames point to the same underlying file.
106 However, it does handle the fact that on DOS-like file systems, forward
107 and backward slashes are equal.
108
109 @end deftypefn
110
111 */
112
113 int
114 filename_ncmp (const char *s1, const char *s2, size_t n)
115 {
116 #if !defined(HAVE_DOS_BASED_FILE_SYSTEM) \
117 && !defined(HAVE_CASE_INSENSITIVE_FILE_SYSTEM)
118 return strncmp(s1, s2, n);
119 #else
120 if (!n)
121 return 0;
122 for (; n > 0; --n)
123 {
124 int c1 = *s1;
125 int c2 = *s2;
126
127 #if defined (HAVE_CASE_INSENSITIVE_FILE_SYSTEM)
128 c1 = TOLOWER (c1);
129 c2 = TOLOWER (c2);
130 #endif
131
132 #if defined (HAVE_DOS_BASED_FILE_SYSTEM)
133 /* On DOS-based file systems, the '/' and the '\' are equivalent. */
134 if (c1 == '/')
135 c1 = '\\';
136 if (c2 == '/')
137 c2 = '\\';
138 #endif
139
140 if (c1 == '\0' || c1 != c2)
141 return (c1 - c2);
142
143 s1++;
144 s2++;
145 }
146 return 0;
147 #endif
148 }
149
150 /*
151
152 @deftypefn Extension hashval_t filename_hash (const void *@var{s})
153
154 Return the hash value for file name @var{s} that will be compared
155 using filename_cmp.
156 This function is for use with hashtab.c hash tables.
157
158 @end deftypefn
159
160 */
161
162 hashval_t
163 filename_hash (const void *s)
164 {
165 /* The cast is for -Wc++-compat. */
166 const unsigned char *str = (const unsigned char *) s;
167 hashval_t r = 0;
168 unsigned char c;
169
170 while ((c = *str++) != 0)
171 {
172 if (c == '\\')
173 c = '/';
174 c = TOLOWER (c);
175 r = r * 67 + c - 113;
176 }
177
178 return r;
179 }
180
181 /*
182
183 @deftypefn Extension int filename_eq (const void *@var{s1}, const void *@var{s2})
184
185 Return non-zero if file names @var{s1} and @var{s2} are equivalent.
186 This function is for use with hashtab.c hash tables.
187
188 @end deftypefn
189
190 */
191
192 int
193 filename_eq (const void *s1, const void *s2)
194 {
195 /* The casts are for -Wc++-compat. */
196 return filename_cmp ((const char *) s1, (const char *) s2) == 0;
197 }
198
199 /*
200
201 @deftypefn Extension int canonical_filename_eq (const char *@var{a}, const char *@var{b})
202
203 Return non-zero if file names @var{a} and @var{b} are equivalent.
204 This function compares the canonical versions of the filenames as returned by
205 @code{lrealpath()}, so that so that different file names pointing to the same
206 underlying file are treated as being identical.
207
208 @end deftypefn
209
210 */
211
212 int
213 canonical_filename_eq (const char * a, const char * b)
214 {
215 char * ca = lrealpath(a);
216 char * cb = lrealpath(b);
217 int res = filename_eq (ca, cb);
218 free (ca);
219 free (cb);
220 return res;
221 }