xref: /openbsd/gnu/usr.bin/cvs/lib/fncase.c (revision 78b63d65)
1 /* fncase.c -- CVS support for case insensitive file systems.
2    Jim Blandy <jimb@cyclic.com>
3 
4    This file is part of GNU CVS.
5 
6    GNU CVS is free software; you can redistribute it and/or modify it
7    under the terms of the GNU General Public License as published by the
8    Free Software Foundation; either version 2, or (at your option) any
9    later version.
10 
11    This program is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14    GNU General Public License for more details.  */
15 
16 #ifdef HAVE_CONFIG_H
17 #include "config.h"
18 #endif
19 
20 #include "system.h"
21 
22 /* The equivalence class mapping for filenames.
23    Windows NT filenames are case-insensitive, but case-preserving.
24    Both / and \ are path element separators.
25    Thus, this table maps both upper and lower case to lower case, and
26    both / and \ to /.  */
27 
28 #if 0
29 main ()
30 {
31   int c;
32 
33   for (c = 0; c < 256; c++)
34     {
35       int t;
36 
37       if (c == '\\')
38         t = '/';
39       else
40         t = tolower (c);
41 
42       if ((c & 0x7) == 0x0)
43          printf ("    ");
44       printf ("0x%02x,", t);
45       if ((c & 0x7) == 0x7)
46          putchar ('\n');
47       else if ((c & 0x7) == 0x3)
48          putchar (' ');
49     }
50 }
51 #endif
52 
53 unsigned char
54 WNT_filename_classes[] =
55 {
56     0x00,0x01,0x02,0x03, 0x04,0x05,0x06,0x07,
57     0x08,0x09,0x0a,0x0b, 0x0c,0x0d,0x0e,0x0f,
58     0x10,0x11,0x12,0x13, 0x14,0x15,0x16,0x17,
59     0x18,0x19,0x1a,0x1b, 0x1c,0x1d,0x1e,0x1f,
60     0x20,0x21,0x22,0x23, 0x24,0x25,0x26,0x27,
61     0x28,0x29,0x2a,0x2b, 0x2c,0x2d,0x2e,0x2f,
62     0x30,0x31,0x32,0x33, 0x34,0x35,0x36,0x37,
63     0x38,0x39,0x3a,0x3b, 0x3c,0x3d,0x3e,0x3f,
64     0x40,0x61,0x62,0x63, 0x64,0x65,0x66,0x67,
65     0x68,0x69,0x6a,0x6b, 0x6c,0x6d,0x6e,0x6f,
66     0x70,0x71,0x72,0x73, 0x74,0x75,0x76,0x77,
67     0x78,0x79,0x7a,0x5b, 0x2f,0x5d,0x5e,0x5f,
68     0x60,0x61,0x62,0x63, 0x64,0x65,0x66,0x67,
69     0x68,0x69,0x6a,0x6b, 0x6c,0x6d,0x6e,0x6f,
70     0x70,0x71,0x72,0x73, 0x74,0x75,0x76,0x77,
71     0x78,0x79,0x7a,0x7b, 0x7c,0x7d,0x7e,0x7f,
72     0x80,0x81,0x82,0x83, 0x84,0x85,0x86,0x87,
73     0x88,0x89,0x8a,0x8b, 0x8c,0x8d,0x8e,0x8f,
74     0x90,0x91,0x92,0x93, 0x94,0x95,0x96,0x97,
75     0x98,0x99,0x9a,0x9b, 0x9c,0x9d,0x9e,0x9f,
76     0xa0,0xa1,0xa2,0xa3, 0xa4,0xa5,0xa6,0xa7,
77     0xa8,0xa9,0xaa,0xab, 0xac,0xad,0xae,0xaf,
78     0xb0,0xb1,0xb2,0xb3, 0xb4,0xb5,0xb6,0xb7,
79     0xb8,0xb9,0xba,0xbb, 0xbc,0xbd,0xbe,0xbf,
80     0xc0,0xc1,0xc2,0xc3, 0xc4,0xc5,0xc6,0xc7,
81     0xc8,0xc9,0xca,0xcb, 0xcc,0xcd,0xce,0xcf,
82     0xd0,0xd1,0xd2,0xd3, 0xd4,0xd5,0xd6,0xd7,
83     0xd8,0xd9,0xda,0xdb, 0xdc,0xdd,0xde,0xdf,
84     0xe0,0xe1,0xe2,0xe3, 0xe4,0xe5,0xe6,0xe7,
85     0xe8,0xe9,0xea,0xeb, 0xec,0xed,0xee,0xef,
86     0xf0,0xf1,0xf2,0xf3, 0xf4,0xf5,0xf6,0xf7,
87     0xf8,0xf9,0xfa,0xfb, 0xfc,0xfd,0xfe,0xff,
88 };
89 
90 /* Like strcmp, but with the appropriate tweaks for file names.
91    Under Windows NT, filenames are case-insensitive but case-preserving,
92    and both \ and / are path element separators.  */
93 int
94 fncmp (const char *n1, const char *n2)
95 {
96     while (*n1 && *n2
97            && (WNT_filename_classes[(unsigned char) *n1]
98 	       == WNT_filename_classes[(unsigned char) *n2]))
99         n1++, n2++;
100     return (WNT_filename_classes[(unsigned char) *n1]
101             - WNT_filename_classes[(unsigned char) *n2]);
102 }
103 
104 /* Fold characters in FILENAME to their canonical forms.
105    If FOLD_FN_CHAR is not #defined, the system provides a default
106    definition for this.  */
107 void
108 fnfold (char *filename)
109 {
110     while (*filename)
111     {
112         *filename = FOLD_FN_CHAR (*filename);
113 	filename++;
114     }
115 }
116