prefix.c revision 117395
1/* Utility to update paths from internal to external forms. 2 Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 3 Free Software Foundation, Inc. 4 5This file is part of GCC. 6 7GCC is free software; you can redistribute it and/or modify it under 8the terms of the GNU Library General Public License as published by 9the Free Software Foundation; either version 2 of the License, or (at 10your option) any later version. 11 12GCC is distributed in the hope that it will be useful, 13but WITHOUT ANY WARRANTY; without even the implied warranty of 14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15Library General Public License for more details. 16 17You should have received a copy of the GNU Library General Public 18License along with GCC; see the file COPYING. If not, write to the Free 19Software Foundation, Inc., 59 Temple Place - Suite 330, 20Boston, MA 02111-1307, USA. */ 21 22/* This file contains routines to update a path, both to canonicalize 23 the directory format and to handle any prefix translation. 24 25 This file must be compiled with -DPREFIX= to specify the "prefix" 26 value used by configure. If a filename does not begin with this 27 prefix, it will not be affected other than by directory canonicalization. 28 29 Each caller of 'update_path' may specify both a filename and 30 a translation prefix and consist of the name of the package that contains 31 the file ("@GCC", "@BINUTIL", "@GNU", etc). 32 33 If the prefix is not specified, the filename will only undergo 34 directory canonicalization. 35 36 If it is specified, the string given by PREFIX will be replaced 37 by the specified prefix (with a '@' in front unless the prefix begins 38 with a '$') and further translation will be done as follows 39 until none of the two conditions below are met: 40 41 1) If the filename begins with '@', the string between the '@' and 42 the end of the name or the first '/' or directory separator will 43 be considered a "key" and looked up as follows: 44 45 -- If this is a Win32 OS, then the Registry will be examined for 46 an entry of "key" in 47 48 HKEY_LOCAL_MACHINE\SOFTWARE\Free Software Foundation\<KEY> 49 50 if found, that value will be used. <KEY> defaults to GCC version 51 string, but can be overridden at configuration time. 52 53 -- If not found (or not a Win32 OS), the environment variable 54 key_ROOT (the value of "key" concatenated with the constant "_ROOT") 55 is tried. If that fails, then PREFIX (see above) is used. 56 57 2) If the filename begins with a '$', the rest of the string up 58 to the end or the first '/' or directory separator will be used 59 as an environment variable, whose value will be returned. 60 61 Once all this is done, any '/' will be converted to DIR_SEPARATOR, 62 if they are different. 63 64 NOTE: using resolve_keyed_path under Win32 requires linking with 65 advapi32.dll. */ 66 67 68#include "config.h" 69#include "system.h" 70#if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY) 71#include <windows.h> 72#endif 73#include "prefix.h" 74 75static const char *std_prefix = PREFIX; 76 77static const char *get_key_value PARAMS ((char *)); 78static char *translate_name PARAMS ((char *)); 79static char *save_string PARAMS ((const char *, int)); 80static void tr PARAMS ((char *, int, int)); 81 82#if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY) 83static char *lookup_key PARAMS ((char *)); 84static HKEY reg_key = (HKEY) INVALID_HANDLE_VALUE; 85#endif 86 87/* Given KEY, as above, return its value. */ 88 89static const char * 90get_key_value (key) 91 char *key; 92{ 93 const char *prefix = 0; 94 char *temp = 0; 95 96#if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY) 97 prefix = lookup_key (key); 98#endif 99 100 if (prefix == 0) 101 prefix = getenv (temp = concat (key, "_ROOT", NULL)); 102 103 if (prefix == 0) 104 prefix = std_prefix; 105 106 if (temp) 107 free (temp); 108 109 return prefix; 110} 111 112/* Return a copy of a string that has been placed in the heap. */ 113 114static char * 115save_string (s, len) 116 const char *s; 117 int len; 118{ 119 char *result = xmalloc (len + 1); 120 121 memcpy (result, s, len); 122 result[len] = 0; 123 return result; 124} 125 126#if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY) 127 128/* Look up "key" in the registry, as above. */ 129 130static char * 131lookup_key (key) 132 char *key; 133{ 134 char *dst; 135 DWORD size; 136 DWORD type; 137 LONG res; 138 139 if (reg_key == (HKEY) INVALID_HANDLE_VALUE) 140 { 141 res = RegOpenKeyExA (HKEY_LOCAL_MACHINE, "SOFTWARE", 0, 142 KEY_READ, ®_key); 143 144 if (res == ERROR_SUCCESS) 145 res = RegOpenKeyExA (reg_key, "Free Software Foundation", 0, 146 KEY_READ, ®_key); 147 148 if (res == ERROR_SUCCESS) 149 res = RegOpenKeyExA (reg_key, WIN32_REGISTRY_KEY, 0, 150 KEY_READ, ®_key); 151 152 if (res != ERROR_SUCCESS) 153 { 154 reg_key = (HKEY) INVALID_HANDLE_VALUE; 155 return 0; 156 } 157 } 158 159 size = 32; 160 dst = (char *) xmalloc (size); 161 162 res = RegQueryValueExA (reg_key, key, 0, &type, dst, &size); 163 if (res == ERROR_MORE_DATA && type == REG_SZ) 164 { 165 dst = (char *) xrealloc (dst, size); 166 res = RegQueryValueExA (reg_key, key, 0, &type, dst, &size); 167 } 168 169 if (type != REG_SZ || res != ERROR_SUCCESS) 170 { 171 free (dst); 172 dst = 0; 173 } 174 175 return dst; 176} 177#endif 178 179/* If NAME, a malloc-ed string, starts with a '@' or '$', apply the 180 translation rules above and return a newly malloc-ed name. 181 Otherwise, return the given name. */ 182 183static char * 184translate_name (name) 185 char *name; 186{ 187 char code; 188 char *key, *old_name; 189 const char *prefix; 190 int keylen; 191 192 for (;;) 193 { 194 code = name[0]; 195 if (code != '@' && code != '$') 196 break; 197 198 for (keylen = 0; 199 (name[keylen + 1] != 0 && !IS_DIR_SEPARATOR (name[keylen + 1])); 200 keylen++) 201 ; 202 203 key = (char *) alloca (keylen + 1); 204 strncpy (key, &name[1], keylen); 205 key[keylen] = 0; 206 207 if (code == '@') 208 { 209 prefix = get_key_value (key); 210 if (prefix == 0) 211 prefix = std_prefix; 212 } 213 else 214 prefix = getenv (key); 215 216 if (prefix == 0) 217 prefix = PREFIX; 218 219 /* We used to strip trailing DIR_SEPARATORs here, but that can 220 sometimes yield a result with no separator when one was coded 221 and intended by the user, causing two path components to run 222 together. */ 223 224 old_name = name; 225 name = concat (prefix, &name[keylen + 1], NULL); 226 free (old_name); 227 } 228 229 return name; 230} 231 232/* In a NUL-terminated STRING, replace character C1 with C2 in-place. */ 233static void 234tr (string, c1, c2) 235 char *string; 236 int c1, c2; 237{ 238 do 239 { 240 if (*string == c1) 241 *string = c2; 242 } 243 while (*string++); 244} 245 246/* Update PATH using KEY if PATH starts with PREFIX. The returned 247 string is always malloc-ed, and the caller is responsible for 248 freeing it. */ 249 250char * 251update_path (path, key) 252 const char *path; 253 const char *key; 254{ 255 char *result, *p; 256 257 if (! strncmp (path, std_prefix, strlen (std_prefix)) && key != 0) 258 { 259 bool free_key = false; 260 261 if (key[0] != '$') 262 { 263 key = concat ("@", key, NULL); 264 free_key = true; 265 } 266 267 result = concat (key, &path[strlen (std_prefix)], NULL); 268 if (free_key) 269 free ((char *) key); 270 result = translate_name (result); 271 } 272 else 273 result = xstrdup (path); 274 275#ifndef ALWAYS_STRIP_DOTDOT 276#define ALWAYS_STRIP_DOTDOT 0 277#endif 278 279 p = result; 280 while (1) 281 { 282 char *src, *dest; 283 284 p = strchr (p, '.'); 285 if (p == NULL) 286 break; 287 /* Look for `/../' */ 288 if (p[1] == '.' 289 && IS_DIR_SEPARATOR (p[2]) 290 && (p != result && IS_DIR_SEPARATOR (p[-1]))) 291 { 292 *p = 0; 293 if (!ALWAYS_STRIP_DOTDOT && access (result, X_OK) == 0) 294 { 295 *p = '.'; 296 break; 297 } 298 else 299 { 300 /* We can't access the dir, so we won't be able to 301 access dir/.. either. Strip out `dir/../'. If `dir' 302 turns out to be `.', strip one more path component. */ 303 dest = p; 304 do 305 { 306 --dest; 307 while (dest != result && IS_DIR_SEPARATOR (*dest)) 308 --dest; 309 while (dest != result && !IS_DIR_SEPARATOR (dest[-1])) 310 --dest; 311 } 312 while (dest != result && *dest == '.'); 313 /* If we have something like `./..' or `/..', don't 314 strip anything more. */ 315 if (*dest == '.' || IS_DIR_SEPARATOR (*dest)) 316 { 317 *p = '.'; 318 break; 319 } 320 src = p + 3; 321 while (IS_DIR_SEPARATOR (*src)) 322 ++src; 323 p = dest; 324 while ((*dest++ = *src++) != 0) 325 ; 326 } 327 } 328 else 329 ++p; 330 } 331 332#ifdef UPDATE_PATH_HOST_CANONICALIZE 333 /* Perform host dependent canonicalization when needed. */ 334 UPDATE_PATH_HOST_CANONICALIZE (result); 335#endif 336 337#ifdef DIR_SEPARATOR_2 338 /* Convert DIR_SEPARATOR_2 to DIR_SEPARATOR. */ 339 if (DIR_SEPARATOR_2 != DIR_SEPARATOR) 340 tr (result, DIR_SEPARATOR_2, DIR_SEPARATOR); 341#endif 342 343#if defined (DIR_SEPARATOR) && !defined (DIR_SEPARATOR_2) 344 if (DIR_SEPARATOR != '/') 345 tr (result, '/', DIR_SEPARATOR); 346#endif 347 348 return result; 349} 350 351/* Reset the standard prefix */ 352void 353set_std_prefix (prefix, len) 354 const char *prefix; 355 int len; 356{ 357 std_prefix = save_string (prefix, len); 358} 359