1 /* Utility to update paths from internal to external forms.
2 Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
3 Free Software Foundation, Inc.
4
5 This file is part of GCC.
6
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU Library General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or (at
10 your option) any later version.
11
12 GCC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 Library General Public License for more details.
16
17 You should have received a copy of the GNU Library General Public
18 License along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
20 Boston, MA 02110-1301, 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 #include "coretypes.h"
71 #include "tm.h"
72 #if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY)
73 #include <windows.h>
74 #endif
75 #include "prefix.h"
76
77 static const char *std_prefix = PREFIX;
78
79 static const char *get_key_value (char *);
80 static char *translate_name (char *);
81 static char *save_string (const char *, int);
82 static void tr (char *, int, int);
83
84 #if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY)
85 static char *lookup_key (char *);
86 static HKEY reg_key = (HKEY) INVALID_HANDLE_VALUE;
87 #endif
88
89 /* Given KEY, as above, return its value. */
90
91 static const char *
get_key_value(char * key)92 get_key_value (char *key)
93 {
94 const char *prefix = 0;
95 char *temp = 0;
96
97 #if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY)
98 prefix = lookup_key (key);
99 #endif
100
101 if (prefix == 0)
102 prefix = getenv (temp = concat (key, "_ROOT", NULL));
103
104 if (prefix == 0)
105 prefix = std_prefix;
106
107 if (temp)
108 free (temp);
109
110 return prefix;
111 }
112
113 /* Return a copy of a string that has been placed in the heap. */
114
115 static char *
save_string(const char * s,int len)116 save_string (const char *s, int len)
117 {
118 char *result = xmalloc (len + 1);
119
120 memcpy (result, s, len);
121 result[len] = 0;
122 return result;
123 }
124
125 #if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY)
126
127 #ifndef WIN32_REGISTRY_KEY
128 # define WIN32_REGISTRY_KEY BASEVER
129 #endif
130
131 /* Look up "key" in the registry, as above. */
132
133 static char *
lookup_key(char * key)134 lookup_key (char *key)
135 {
136 char *dst;
137 DWORD size;
138 DWORD type;
139 LONG res;
140
141 if (reg_key == (HKEY) INVALID_HANDLE_VALUE)
142 {
143 res = RegOpenKeyExA (HKEY_LOCAL_MACHINE, "SOFTWARE", 0,
144 KEY_READ, ®_key);
145
146 if (res == ERROR_SUCCESS)
147 res = RegOpenKeyExA (reg_key, "Free Software Foundation", 0,
148 KEY_READ, ®_key);
149
150 if (res == ERROR_SUCCESS)
151 res = RegOpenKeyExA (reg_key, WIN32_REGISTRY_KEY, 0,
152 KEY_READ, ®_key);
153
154 if (res != ERROR_SUCCESS)
155 {
156 reg_key = (HKEY) INVALID_HANDLE_VALUE;
157 return 0;
158 }
159 }
160
161 size = 32;
162 dst = xmalloc (size);
163
164 res = RegQueryValueExA (reg_key, key, 0, &type, (LPBYTE) dst, &size);
165 if (res == ERROR_MORE_DATA && type == REG_SZ)
166 {
167 dst = xrealloc (dst, size);
168 res = RegQueryValueExA (reg_key, key, 0, &type, (LPBYTE) dst, &size);
169 }
170
171 if (type != REG_SZ || res != ERROR_SUCCESS)
172 {
173 free (dst);
174 dst = 0;
175 }
176
177 return dst;
178 }
179 #endif
180
181 /* If NAME, a malloc-ed string, starts with a '@' or '$', apply the
182 translation rules above and return a newly malloc-ed name.
183 Otherwise, return the given name. */
184
185 static char *
translate_name(char * name)186 translate_name (char *name)
187 {
188 char code;
189 char *key, *old_name;
190 const char *prefix;
191 int keylen;
192
193 for (;;)
194 {
195 code = name[0];
196 if (code != '@' && code != '$')
197 break;
198
199 for (keylen = 0;
200 (name[keylen + 1] != 0 && !IS_DIR_SEPARATOR (name[keylen + 1]));
201 keylen++)
202 ;
203
204 key = alloca (keylen + 1);
205 strncpy (key, &name[1], keylen);
206 key[keylen] = 0;
207
208 if (code == '@')
209 {
210 prefix = get_key_value (key);
211 if (prefix == 0)
212 prefix = std_prefix;
213 }
214 else
215 prefix = getenv (key);
216
217 if (prefix == 0)
218 prefix = PREFIX;
219
220 /* We used to strip trailing DIR_SEPARATORs here, but that can
221 sometimes yield a result with no separator when one was coded
222 and intended by the user, causing two path components to run
223 together. */
224
225 old_name = name;
226 name = concat (prefix, &name[keylen + 1], NULL);
227 free (old_name);
228 }
229
230 return name;
231 }
232
233 /* In a NUL-terminated STRING, replace character C1 with C2 in-place. */
234 static void
tr(char * string,int c1,int c2)235 tr (char *string, int c1, int c2)
236 {
237 do
238 {
239 if (*string == c1)
240 *string = c2;
241 }
242 while (*string++);
243 }
244
245 /* Update PATH using KEY if PATH starts with PREFIX as a directory.
246 The returned string is always malloc-ed, and the caller is
247 responsible for freeing it. */
248
249 char *
update_path(const char * path,const char * key)250 update_path (const char *path, const char *key)
251 {
252 char *result, *p;
253 const int len = strlen (std_prefix);
254
255 if (! strncmp (path, std_prefix, len)
256 && (IS_DIR_SEPARATOR(path[len])
257 || path[len] == '\0')
258 && key != 0)
259 {
260 bool free_key = false;
261
262 if (key[0] != '$')
263 {
264 key = concat ("@", key, NULL);
265 free_key = true;
266 }
267
268 result = concat (key, &path[len], NULL);
269 if (free_key)
270 free ((char *) key);
271 result = translate_name (result);
272 }
273 else
274 result = xstrdup (path);
275
276 #ifndef ALWAYS_STRIP_DOTDOT
277 #define ALWAYS_STRIP_DOTDOT 0
278 #endif
279
280 p = result;
281 while (1)
282 {
283 char *src, *dest;
284
285 p = strchr (p, '.');
286 if (p == NULL)
287 break;
288 /* Look for `/../' */
289 if (p[1] == '.'
290 && IS_DIR_SEPARATOR (p[2])
291 && (p != result && IS_DIR_SEPARATOR (p[-1])))
292 {
293 *p = 0;
294 if (!ALWAYS_STRIP_DOTDOT && access (result, X_OK) == 0)
295 {
296 *p = '.';
297 break;
298 }
299 else
300 {
301 /* We can't access the dir, so we won't be able to
302 access dir/.. either. Strip out `dir/../'. If `dir'
303 turns out to be `.', strip one more path component. */
304 dest = p;
305 do
306 {
307 --dest;
308 while (dest != result && IS_DIR_SEPARATOR (*dest))
309 --dest;
310 while (dest != result && !IS_DIR_SEPARATOR (dest[-1]))
311 --dest;
312 }
313 while (dest != result && *dest == '.');
314 /* If we have something like `./..' or `/..', don't
315 strip anything more. */
316 if (*dest == '.' || IS_DIR_SEPARATOR (*dest))
317 {
318 *p = '.';
319 break;
320 }
321 src = p + 3;
322 while (IS_DIR_SEPARATOR (*src))
323 ++src;
324 p = dest;
325 while ((*dest++ = *src++) != 0)
326 ;
327 }
328 }
329 else
330 ++p;
331 }
332
333 #ifdef UPDATE_PATH_HOST_CANONICALIZE
334 /* Perform host dependent canonicalization when needed. */
335 UPDATE_PATH_HOST_CANONICALIZE (result);
336 #endif
337
338 #ifdef DIR_SEPARATOR_2
339 /* Convert DIR_SEPARATOR_2 to DIR_SEPARATOR. */
340 if (DIR_SEPARATOR_2 != DIR_SEPARATOR)
341 tr (result, DIR_SEPARATOR_2, DIR_SEPARATOR);
342 #endif
343
344 #if defined (DIR_SEPARATOR) && !defined (DIR_SEPARATOR_2)
345 if (DIR_SEPARATOR != '/')
346 tr (result, '/', DIR_SEPARATOR);
347 #endif
348
349 return result;
350 }
351
352 /* Reset the standard prefix. */
353 void
set_std_prefix(const char * prefix,int len)354 set_std_prefix (const char *prefix, int len)
355 {
356 std_prefix = save_string (prefix, len);
357 }
358