1 /* File name comparison routine.
2 
3    Copyright (C) 2007 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
filename_cmp(const char * s1,const char * s2)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
filename_ncmp(const char * s1,const char * s2,size_t n)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
filename_hash(const void * s)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
filename_eq(const void * s1,const void * s2)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
canonical_filename_eq(const char * a,const char * b)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 }
222