1 /****************************************************************************
2 * Copyright (c) 1998-2011,2012 Free Software Foundation, Inc. *
3 * *
4 * Permission is hereby granted, free of charge, to any person obtaining a *
5 * copy of this software and associated documentation files (the *
6 * "Software"), to deal in the Software without restriction, including *
7 * without limitation the rights to use, copy, modify, merge, publish, *
8 * distribute, distribute with modifications, sublicense, and/or sell *
9 * copies of the Software, and to permit persons to whom the Software is *
10 * furnished to do so, subject to the following conditions: *
11 * *
12 * The above copyright notice and this permission notice shall be included *
13 * in all copies or substantial portions of the Software. *
14 * *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS *
16 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
18 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
19 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR *
20 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR *
21 * THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
22 * *
23 * Except as contained in this notice, the name(s) of the above copyright *
24 * holders shall not be used in advertising or otherwise to promote the *
25 * sale, use or other dealings in this Software without prior written *
26 * authorization. *
27 ****************************************************************************/
28
29 /****************************************************************************
30 * Author: Thomas E. Dickey *
31 ****************************************************************************/
32
33 #include <curses.priv.h>
34
35 #include <ctype.h>
36
37 #include <tic.h>
38
39 MODULE_ID("$Id: access.c,v 1.23 2012/09/01 19:21:29 tom Exp $")
40
41 #ifdef __TANDEM
42 #define ROOT_UID 65535
43 #endif
44
45 #ifndef ROOT_UID
46 #define ROOT_UID 0
47 #endif
48
49 #define LOWERCASE(c) ((isalpha(UChar(c)) && isupper(UChar(c))) ? tolower(UChar(c)) : (c))
50
NCURSES_EXPORT(char *)51 NCURSES_EXPORT(char *)
52 _nc_rootname(char *path)
53 {
54 char *result = _nc_basename(path);
55 #if !MIXEDCASE_FILENAMES || defined(PROG_EXT)
56 static char *temp;
57 char *s;
58
59 temp = strdup(result);
60 result = temp;
61 #if !MIXEDCASE_FILENAMES
62 for (s = result; *s != '\0'; ++s) {
63 *s = (char) LOWERCASE(*s);
64 }
65 #endif
66 #if defined(PROG_EXT)
67 if ((s = strrchr(result, '.')) != 0) {
68 if (!strcmp(s, PROG_EXT))
69 *s = '\0';
70 }
71 #endif
72 #endif
73 return result;
74 }
75
76 /*
77 * Check if a string appears to be an absolute pathname.
78 */
79 NCURSES_EXPORT(bool)
_nc_is_abs_path(const char * path)80 _nc_is_abs_path(const char *path)
81 {
82 #if defined(__EMX__) || defined(__DJGPP__)
83 #define is_pathname(s) ((((s) != 0) && ((s)[0] == '/')) \
84 || (((s)[0] != 0) && ((s)[1] == ':')))
85 #else
86 #define is_pathname(s) ((s) != 0 && (s)[0] == '/')
87 #endif
88 return is_pathname(path);
89 }
90
91 /*
92 * Return index of the basename
93 */
94 NCURSES_EXPORT(unsigned)
_nc_pathlast(const char * path)95 _nc_pathlast(const char *path)
96 {
97 const char *test = strrchr(path, '/');
98 #ifdef __EMX__
99 if (test == 0)
100 test = strrchr(path, '\\');
101 #endif
102 if (test == 0)
103 test = path;
104 else
105 test++;
106 return (unsigned) (test - path);
107 }
108
109 NCURSES_EXPORT(char *)
_nc_basename(char * path)110 _nc_basename(char *path)
111 {
112 return path + _nc_pathlast(path);
113 }
114
115 NCURSES_EXPORT(int)
_nc_access(const char * path,int mode)116 _nc_access(const char *path, int mode)
117 {
118 int result;
119
120 if (path == 0) {
121 result = -1;
122 } else if (access(path, mode) < 0) {
123 if ((mode & W_OK) != 0
124 && errno == ENOENT
125 && strlen(path) < PATH_MAX) {
126 char head[PATH_MAX];
127 char *leaf;
128
129 _nc_STRCPY(head, path, sizeof(head));
130 leaf = _nc_basename(head);
131 if (leaf == 0)
132 leaf = head;
133 *leaf = '\0';
134 if (head == leaf)
135 _nc_STRCPY(head, ".", sizeof(head));
136
137 result = access(head, R_OK | W_OK | X_OK);
138 } else {
139 result = -1;
140 }
141 } else {
142 result = 0;
143 }
144 return result;
145 }
146
147 NCURSES_EXPORT(bool)
_nc_is_dir_path(const char * path)148 _nc_is_dir_path(const char *path)
149 {
150 bool result = FALSE;
151 struct stat sb;
152
153 if (stat(path, &sb) == 0
154 && S_ISDIR(sb.st_mode)) {
155 result = TRUE;
156 }
157 return result;
158 }
159
160 NCURSES_EXPORT(bool)
_nc_is_file_path(const char * path)161 _nc_is_file_path(const char *path)
162 {
163 bool result = FALSE;
164 struct stat sb;
165
166 if (stat(path, &sb) == 0
167 && S_ISREG(sb.st_mode)) {
168 result = TRUE;
169 }
170 return result;
171 }
172
173 #ifndef USE_ROOT_ENVIRON
174 /*
175 * Returns true if we allow application to use environment variables that are
176 * used for searching lists of directories, etc.
177 */
178 NCURSES_EXPORT(int)
_nc_env_access(void)179 _nc_env_access(void)
180 {
181 #if HAVE_ISSETUGID
182 if (issetugid())
183 return FALSE;
184 #elif HAVE_GETEUID && HAVE_GETEGID
185 if (getuid() != geteuid()
186 || getgid() != getegid())
187 return FALSE;
188 #endif
189 /* ...finally, disallow root */
190 return (getuid() != ROOT_UID) && (geteuid() != ROOT_UID);
191 }
192 #endif
193