1 /**************************************************************************** 2 * Copyright (c) 1998-2006,2007 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 #include <sys/stat.h> 37 38 #include <tic.h> 39 #include <nc_alloc.h> 40 41 MODULE_ID("$Id: access.c,v 1.14 2007/11/18 00:57:53 tom Exp $") 42 43 #define LOWERCASE(c) ((isalpha(UChar(c)) && isupper(UChar(c))) ? tolower(UChar(c)) : (c)) 44 45 NCURSES_EXPORT(char *) 46 _nc_rootname(char *path) 47 { 48 char *result = _nc_basename(path); 49 #if !MIXEDCASE_FILENAMES || defined(PROG_EXT) 50 static char *temp; 51 char *s; 52 53 temp = strdup(result); 54 result = temp; 55 #if !MIXEDCASE_FILENAMES 56 for (s = result; *s != '\0'; ++s) { 57 *s = LOWERCASE(*s); 58 } 59 #endif 60 #if defined(PROG_EXT) 61 if ((s = strrchr(result, '.')) != 0) { 62 if (!strcmp(s, PROG_EXT)) 63 *s = '\0'; 64 } 65 #endif 66 #endif 67 return result; 68 } 69 70 /* 71 * Check if a string appears to be an absolute pathname. 72 */ 73 NCURSES_EXPORT(bool) 74 _nc_is_abs_path(const char *path) 75 { 76 #if defined(__EMX__) || defined(__DJGPP__) 77 #define is_pathname(s) ((((s) != 0) && ((s)[0] == '/')) \ 78 || (((s)[0] != 0) && ((s)[1] == ':'))) 79 #else 80 #define is_pathname(s) ((s) != 0 && (s)[0] == '/') 81 #endif 82 return is_pathname(path); 83 } 84 85 /* 86 * Return index of the basename 87 */ 88 NCURSES_EXPORT(unsigned) 89 _nc_pathlast(const char *path) 90 { 91 const char *test = strrchr(path, '/'); 92 #ifdef __EMX__ 93 if (test == 0) 94 test = strrchr(path, '\\'); 95 #endif 96 if (test == 0) 97 test = path; 98 else 99 test++; 100 return (test - path); 101 } 102 103 NCURSES_EXPORT(char *) 104 _nc_basename(char *path) 105 { 106 return path + _nc_pathlast(path); 107 } 108 109 NCURSES_EXPORT(int) 110 _nc_access(const char *path, int mode) 111 { 112 if (access(path, mode) < 0) { 113 if ((mode & W_OK) != 0 114 && errno == ENOENT 115 && strlen(path) < PATH_MAX) { 116 char head[PATH_MAX]; 117 char *leaf = _nc_basename(strcpy(head, path)); 118 119 if (leaf == 0) 120 leaf = head; 121 *leaf = '\0'; 122 if (head == leaf) 123 (void) strcpy(head, "."); 124 125 return access(head, R_OK | W_OK | X_OK); 126 } 127 return -1; 128 } 129 return 0; 130 } 131 132 NCURSES_EXPORT(bool) 133 _nc_is_dir_path(const char *path) 134 { 135 bool result = FALSE; 136 struct stat sb; 137 138 if (stat(path, &sb) == 0 139 && (sb.st_mode & S_IFMT) == S_IFDIR) { 140 result = TRUE; 141 } 142 return result; 143 } 144 145 NCURSES_EXPORT(bool) 146 _nc_is_file_path(const char *path) 147 { 148 bool result = FALSE; 149 struct stat sb; 150 151 if (stat(path, &sb) == 0 152 && (sb.st_mode & S_IFMT) == S_IFREG) { 153 result = TRUE; 154 } 155 return result; 156 } 157 158 #ifndef USE_ROOT_ENVIRON 159 /* 160 * Returns true if we allow application to use environment variables that are 161 * used for searching lists of directories, etc. 162 */ 163 NCURSES_EXPORT(int) 164 _nc_env_access(void) 165 { 166 #if HAVE_ISSETUGID 167 if (issetugid()) 168 return FALSE; 169 #elif HAVE_GETEUID && HAVE_GETEGID 170 if (getuid() != geteuid() 171 || getgid() != getegid()) 172 return FALSE; 173 #endif 174 return getuid() != 0 && geteuid() != 0; /* ...finally, disallow root */ 175 } 176 #endif 177