1 /* Utility to update paths from internal to external forms. 2 Copyright (C) 1997-2018 Free Software Foundation, Inc. 3 4 This file is part of GCC. 5 6 GCC is free software; you can redistribute it and/or modify it under 7 the terms of the GNU Library General Public License as published by 8 the Free Software Foundation; either version 3 of the License, or (at 9 your option) any later version. 10 11 GCC 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 GNU 14 Library General Public License for more details. 15 16 You should have received a copy of the GNU Library General Public 17 License along with GCC; see the file COPYING3. If not see 18 <http://www.gnu.org/licenses/>. */ 19 20 /* This file contains routines to update a path, both to canonicalize 21 the directory format and to handle any prefix translation. 22 23 This file must be compiled with -DPREFIX= to specify the "prefix" 24 value used by configure. If a filename does not begin with this 25 prefix, it will not be affected other than by directory canonicalization. 26 27 Each caller of 'update_path' may specify both a filename and 28 a translation prefix and consist of the name of the package that contains 29 the file ("@GCC", "@BINUTIL", "@GNU", etc). 30 31 If the prefix is not specified, the filename will only undergo 32 directory canonicalization. 33 34 If it is specified, the string given by PREFIX will be replaced 35 by the specified prefix (with a '@' in front unless the prefix begins 36 with a '$') and further translation will be done as follows 37 until none of the two conditions below are met: 38 39 1) If the filename begins with '@', the string between the '@' and 40 the end of the name or the first '/' or directory separator will 41 be considered a "key" and looked up as follows: 42 43 -- If this is a Win32 OS, then the Registry will be examined for 44 an entry of "key" in 45 46 HKEY_LOCAL_MACHINE\SOFTWARE\Free Software Foundation\<KEY> 47 48 if found, that value will be used. <KEY> defaults to GCC version 49 string, but can be overridden at configuration time. 50 51 -- If not found (or not a Win32 OS), the environment variable 52 key_ROOT (the value of "key" concatenated with the constant "_ROOT") 53 is tried. If that fails, then PREFIX (see above) is used. 54 55 2) If the filename begins with a '$', the rest of the string up 56 to the end or the first '/' or directory separator will be used 57 as an environment variable, whose value will be returned. 58 59 Once all this is done, any '/' will be converted to DIR_SEPARATOR, 60 if they are different. 61 62 NOTE: using resolve_keyed_path under Win32 requires linking with 63 advapi32.dll. */ 64 65 66 #include "config.h" 67 #include "system.h" 68 #include "coretypes.h" 69 #if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY) 70 #include <windows.h> 71 #endif 72 #include "prefix.h" 73 #include "common/common-target.h" 74 75 static const char *std_prefix = PREFIX; 76 77 static const char *get_key_value (char *); 78 static char *translate_name (char *); 79 static char *save_string (const char *, int); 80 static void tr (char *, int, int); 81 82 #if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY) 83 static char *lookup_key (char *); 84 static HKEY reg_key = (HKEY) INVALID_HANDLE_VALUE; 85 #endif 86 87 /* Given KEY, as above, return its value. */ 88 89 static const char * 90 get_key_value (char *key) 91 { 92 const char *prefix = 0; 93 char *temp = 0; 94 95 #if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY) 96 prefix = lookup_key (key); 97 #endif 98 99 if (prefix == 0) 100 prefix = getenv (temp = concat (key, "_ROOT", NULL)); 101 102 if (prefix == 0) 103 prefix = std_prefix; 104 105 free (temp); 106 107 return prefix; 108 } 109 110 /* Return a copy of a string that has been placed in the heap. */ 111 112 static char * 113 save_string (const char *s, int len) 114 { 115 char *result = XNEWVEC (char, len + 1); 116 117 memcpy (result, s, len); 118 result[len] = 0; 119 return result; 120 } 121 122 #if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY) 123 124 #ifndef WIN32_REGISTRY_KEY 125 # define WIN32_REGISTRY_KEY BASEVER 126 #endif 127 128 /* Look up "key" in the registry, as above. */ 129 130 static char * 131 lookup_key (char *key) 132 { 133 char *dst; 134 DWORD size; 135 DWORD type; 136 LONG res; 137 138 if (reg_key == (HKEY) INVALID_HANDLE_VALUE) 139 { 140 res = RegOpenKeyExA (HKEY_LOCAL_MACHINE, "SOFTWARE", 0, 141 KEY_READ, ®_key); 142 143 if (res == ERROR_SUCCESS) 144 res = RegOpenKeyExA (reg_key, "Free Software Foundation", 0, 145 KEY_READ, ®_key); 146 147 if (res == ERROR_SUCCESS) 148 res = RegOpenKeyExA (reg_key, WIN32_REGISTRY_KEY, 0, 149 KEY_READ, ®_key); 150 151 if (res != ERROR_SUCCESS) 152 { 153 reg_key = (HKEY) INVALID_HANDLE_VALUE; 154 return 0; 155 } 156 } 157 158 size = 32; 159 dst = XNEWVEC (char, size); 160 161 res = RegQueryValueExA (reg_key, key, 0, &type, (LPBYTE) dst, &size); 162 if (res == ERROR_MORE_DATA && type == REG_SZ) 163 { 164 dst = XRESIZEVEC (char, dst, size); 165 res = RegQueryValueExA (reg_key, key, 0, &type, (LPBYTE) dst, &size); 166 } 167 168 if (type != REG_SZ || res != ERROR_SUCCESS) 169 { 170 free (dst); 171 dst = 0; 172 } 173 174 return dst; 175 } 176 #endif 177 178 /* If NAME, a malloc-ed string, starts with a '@' or '$', apply the 179 translation rules above and return a newly malloc-ed name. 180 Otherwise, return the given name. */ 181 182 static char * 183 translate_name (char *name) 184 { 185 char code; 186 char *key, *old_name; 187 const char *prefix; 188 int keylen; 189 190 for (;;) 191 { 192 code = name[0]; 193 if (code != '@' && code != '$') 194 break; 195 196 for (keylen = 0; 197 (name[keylen + 1] != 0 && !IS_DIR_SEPARATOR (name[keylen + 1])); 198 keylen++) 199 ; 200 201 key = (char *) alloca (keylen + 1); 202 memcpy (key, &name[1], keylen); 203 key[keylen] = 0; 204 205 if (code == '@') 206 { 207 prefix = get_key_value (key); 208 if (prefix == 0) 209 prefix = std_prefix; 210 } 211 else 212 prefix = getenv (key); 213 214 if (prefix == 0) 215 prefix = PREFIX; 216 217 /* We used to strip trailing DIR_SEPARATORs here, but that can 218 sometimes yield a result with no separator when one was coded 219 and intended by the user, causing two path components to run 220 together. */ 221 222 old_name = name; 223 name = concat (prefix, &name[keylen + 1], NULL); 224 free (old_name); 225 } 226 227 return name; 228 } 229 230 /* In a NUL-terminated STRING, replace character C1 with C2 in-place. */ 231 static void 232 tr (char *string, int c1, int c2) 233 { 234 do 235 { 236 if (*string == c1) 237 *string = c2; 238 } 239 while (*string++); 240 } 241 242 /* Update PATH using KEY if PATH starts with PREFIX as a directory. 243 The returned string is always malloc-ed, and the caller is 244 responsible for freeing it. */ 245 246 char * 247 update_path (const char *path, const char *key) 248 { 249 char *result, *p; 250 const int len = strlen (std_prefix); 251 252 if (! filename_ncmp (path, std_prefix, len) 253 && (IS_DIR_SEPARATOR (path[len]) 254 || path[len] == '\0') 255 && key != 0) 256 { 257 bool free_key = false; 258 259 if (key[0] != '$') 260 { 261 key = concat ("@", key, NULL); 262 free_key = true; 263 } 264 265 result = concat (key, &path[len], NULL); 266 if (free_key) 267 free (CONST_CAST (char *, key)); 268 result = translate_name (result); 269 } 270 else 271 result = xstrdup (path); 272 273 p = result; 274 while (1) 275 { 276 char *src, *dest; 277 278 p = strchr (p, '.'); 279 if (p == NULL) 280 break; 281 /* Look for `/../' */ 282 if (p[1] == '.' 283 && IS_DIR_SEPARATOR (p[2]) 284 && (p != result && IS_DIR_SEPARATOR (p[-1]))) 285 { 286 *p = 0; 287 if (!targetm_common.always_strip_dotdot 288 && access (result, X_OK) == 0) 289 { 290 *p = '.'; 291 break; 292 } 293 else 294 { 295 /* We can't access the dir, so we won't be able to 296 access dir/.. either. Strip out `dir/../'. If `dir' 297 turns out to be `.', strip one more path component. */ 298 dest = p; 299 do 300 { 301 --dest; 302 while (dest != result && IS_DIR_SEPARATOR (*dest)) 303 --dest; 304 while (dest != result && !IS_DIR_SEPARATOR (dest[-1])) 305 --dest; 306 } 307 while (dest != result && *dest == '.'); 308 /* If we have something like `./..' or `/..', don't 309 strip anything more. */ 310 if (*dest == '.' || IS_DIR_SEPARATOR (*dest)) 311 { 312 *p = '.'; 313 break; 314 } 315 src = p + 3; 316 while (IS_DIR_SEPARATOR (*src)) 317 ++src; 318 p = dest; 319 while ((*dest++ = *src++) != 0) 320 ; 321 } 322 } 323 else 324 ++p; 325 } 326 327 #ifdef UPDATE_PATH_HOST_CANONICALIZE 328 /* Perform host dependent canonicalization when needed. */ 329 UPDATE_PATH_HOST_CANONICALIZE (result); 330 #endif 331 332 #ifdef DIR_SEPARATOR_2 333 /* Convert DIR_SEPARATOR_2 to DIR_SEPARATOR. */ 334 if (DIR_SEPARATOR_2 != DIR_SEPARATOR) 335 tr (result, DIR_SEPARATOR_2, DIR_SEPARATOR); 336 #endif 337 338 #if defined (DIR_SEPARATOR) && !defined (DIR_SEPARATOR_2) 339 if (DIR_SEPARATOR != '/') 340 tr (result, '/', DIR_SEPARATOR); 341 #endif 342 343 return result; 344 } 345 346 /* Reset the standard prefix. */ 347 void 348 set_std_prefix (const char *prefix, int len) 349 { 350 std_prefix = save_string (prefix, len); 351 } 352