- Fix broken handling of order-only prereqs in secondary expansion
[make.git] / vpath.c
blobf5fe1cadc5efeda66a79f4f633cf5319c8ba9672
1 /* Implementation of pattern-matching file search paths for GNU Make.
2 Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software
4 Foundation, Inc.
5 This file is part of GNU Make.
7 GNU Make is free software; you can redistribute it and/or modify it under the
8 terms of the GNU General Public License as published by the Free Software
9 Foundation; either version 3 of the License, or (at your option) any later
10 version.
12 GNU Make is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
14 A PARTICULAR PURPOSE. See the GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License along with
17 this program. If not, see <http://www.gnu.org/licenses/>. */
19 #include "make.h"
20 #include "filedef.h"
21 #include "variable.h"
22 #ifdef WINDOWS32
23 #include "pathstuff.h"
24 #endif
27 /* Structure used to represent a selective VPATH searchpath. */
29 struct vpath
31 struct vpath *next; /* Pointer to next struct in the linked list. */
32 const char *pattern;/* The pattern to match. */
33 const char *percent;/* Pointer into `pattern' where the `%' is. */
34 unsigned int patlen;/* Length of the pattern. */
35 const char **searchpath; /* Null-terminated list of directories. */
36 unsigned int maxlen;/* Maximum length of any entry in the list. */
39 /* Linked-list of all selective VPATHs. */
41 static struct vpath *vpaths;
43 /* Structure for the general VPATH given in the variable. */
45 static struct vpath *general_vpath;
47 /* Structure for GPATH given in the variable. */
49 static struct vpath *gpaths;
52 /* Reverse the chain of selective VPATH lists so they will be searched in the
53 order given in the makefiles and construct the list from the VPATH
54 variable. */
56 void
57 build_vpath_lists ()
59 register struct vpath *new = 0;
60 register struct vpath *old, *nexto;
61 register char *p;
63 /* Reverse the chain. */
64 for (old = vpaths; old != 0; old = nexto)
66 nexto = old->next;
67 old->next = new;
68 new = old;
71 vpaths = new;
73 /* If there is a VPATH variable with a nonnull value, construct the
74 general VPATH list from it. We use variable_expand rather than just
75 calling lookup_variable so that it will be recursively expanded. */
78 /* Turn off --warn-undefined-variables while we expand SHELL and IFS. */
79 int save = warn_undefined_variables_flag;
80 warn_undefined_variables_flag = 0;
82 p = variable_expand ("$(strip $(VPATH))");
84 warn_undefined_variables_flag = save;
87 if (*p != '\0')
89 /* Save the list of vpaths. */
90 struct vpath *save_vpaths = vpaths;
91 char gp[] = "%";
93 /* Empty `vpaths' so the new one will have no next, and `vpaths'
94 will still be nil if P contains no existing directories. */
95 vpaths = 0;
97 /* Parse P. */
98 construct_vpath_list (gp, p);
100 /* Store the created path as the general path,
101 and restore the old list of vpaths. */
102 general_vpath = vpaths;
103 vpaths = save_vpaths;
106 /* If there is a GPATH variable with a nonnull value, construct the
107 GPATH list from it. We use variable_expand rather than just
108 calling lookup_variable so that it will be recursively expanded. */
111 /* Turn off --warn-undefined-variables while we expand SHELL and IFS. */
112 int save = warn_undefined_variables_flag;
113 warn_undefined_variables_flag = 0;
115 p = variable_expand ("$(strip $(GPATH))");
117 warn_undefined_variables_flag = save;
120 if (*p != '\0')
122 /* Save the list of vpaths. */
123 struct vpath *save_vpaths = vpaths;
124 char gp[] = "%";
126 /* Empty `vpaths' so the new one will have no next, and `vpaths'
127 will still be nil if P contains no existing directories. */
128 vpaths = 0;
130 /* Parse P. */
131 construct_vpath_list (gp, p);
133 /* Store the created path as the GPATH,
134 and restore the old list of vpaths. */
135 gpaths = vpaths;
136 vpaths = save_vpaths;
140 /* Construct the VPATH listing for the pattern and searchpath given.
142 This function is called to generate selective VPATH lists and also for
143 the general VPATH list (which is in fact just a selective VPATH that
144 is applied to everything). The returned pointer is either put in the
145 linked list of all selective VPATH lists or in the GENERAL_VPATH
146 variable.
148 If SEARCHPATH is nil, remove all previous listings with the same
149 pattern. If PATTERN is nil, remove all VPATH listings. Existing
150 and readable directories that are not "." given in the searchpath
151 separated by the path element separator (defined in make.h) are
152 loaded into the directory hash table if they are not there already
153 and put in the VPATH searchpath for the given pattern with trailing
154 slashes stripped off if present (and if the directory is not the
155 root, "/"). The length of the longest entry in the list is put in
156 the structure as well. The new entry will be at the head of the
157 VPATHS chain. */
159 void
160 construct_vpath_list (char *pattern, char *dirpath)
162 unsigned int elem;
163 char *p;
164 const char **vpath;
165 unsigned int maxvpath;
166 unsigned int maxelem;
167 const char *percent = NULL;
169 if (pattern != 0)
170 percent = find_percent (pattern);
172 if (dirpath == 0)
174 /* Remove matching listings. */
175 struct vpath *path, *lastpath;
177 lastpath = 0;
178 path = vpaths;
179 while (path != 0)
181 struct vpath *next = path->next;
183 if (pattern == 0
184 || (((percent == 0 && path->percent == 0)
185 || (percent - pattern == path->percent - path->pattern))
186 && streq (pattern, path->pattern)))
188 /* Remove it from the linked list. */
189 if (lastpath == 0)
190 vpaths = path->next;
191 else
192 lastpath->next = next;
194 /* Free its unused storage. */
195 free (path->searchpath);
196 free (path);
198 else
199 lastpath = path;
201 path = next;
204 return;
207 #ifdef WINDOWS32
208 convert_vpath_to_windows32(dirpath, ';');
209 #endif
211 /* Skip over any initial separators and blanks. */
212 while (*dirpath == PATH_SEPARATOR_CHAR || isblank ((unsigned char)*dirpath))
213 ++dirpath;
215 /* Figure out the maximum number of VPATH entries and put it in
216 MAXELEM. We start with 2, one before the first separator and one
217 nil (the list terminator) and increment our estimated number for
218 each separator or blank we find. */
219 maxelem = 2;
220 p = dirpath;
221 while (*p != '\0')
222 if (*p++ == PATH_SEPARATOR_CHAR || isblank ((unsigned char)*p))
223 ++maxelem;
225 vpath = xmalloc (maxelem * sizeof (const char *));
226 maxvpath = 0;
228 elem = 0;
229 p = dirpath;
230 while (*p != '\0')
232 char *v;
233 unsigned int len;
235 /* Find the end of this entry. */
236 v = p;
237 while (*p != '\0'
238 #if defined(HAVE_DOS_PATHS) && (PATH_SEPARATOR_CHAR == ':')
239 /* Platforms whose PATH_SEPARATOR_CHAR is ':' and which
240 also define HAVE_DOS_PATHS would like us to recognize
241 colons after the drive letter in the likes of
242 "D:/foo/bar:C:/xyzzy". */
243 && (*p != PATH_SEPARATOR_CHAR
244 || (p == v + 1 && (p[1] == '/' || p[1] == '\\')))
245 #else
246 && *p != PATH_SEPARATOR_CHAR
247 #endif
248 && !isblank ((unsigned char)*p))
249 ++p;
251 len = p - v;
252 /* Make sure there's no trailing slash,
253 but still allow "/" as a directory. */
254 #if defined(__MSDOS__) || defined(__EMX__) || defined(HAVE_DOS_PATHS)
255 /* We need also to leave alone a trailing slash in "d:/". */
256 if (len > 3 || (len > 1 && v[1] != ':'))
257 #endif
258 if (len > 1 && p[-1] == '/')
259 --len;
261 /* Put the directory on the vpath list. */
262 if (len > 1 || *v != '.')
264 vpath[elem++] = dir_name (strcache_add_len (v, len));
265 if (len > maxvpath)
266 maxvpath = len;
269 /* Skip over separators and blanks between entries. */
270 while (*p == PATH_SEPARATOR_CHAR || isblank ((unsigned char)*p))
271 ++p;
274 if (elem > 0)
276 struct vpath *path;
277 /* ELEM is now incremented one element past the last
278 entry, to where the nil-pointer terminator goes.
279 Usually this is maxelem - 1. If not, shrink down. */
280 if (elem < (maxelem - 1))
281 vpath = xrealloc (vpath, (elem+1) * sizeof (const char *));
283 /* Put the nil-pointer terminator on the end of the VPATH list. */
284 vpath[elem] = NULL;
286 /* Construct the vpath structure and put it into the linked list. */
287 path = xmalloc (sizeof (struct vpath));
288 path->searchpath = vpath;
289 path->maxlen = maxvpath;
290 path->next = vpaths;
291 vpaths = path;
293 /* Set up the members. */
294 path->pattern = strcache_add (pattern);
295 path->patlen = strlen (pattern);
296 path->percent = percent ? path->pattern + (percent - pattern) : 0;
298 else
299 /* There were no entries, so free whatever space we allocated. */
300 free (vpath);
303 /* Search the GPATH list for a pathname string that matches the one passed
304 in. If it is found, return 1. Otherwise we return 0. */
307 gpath_search (const char *file, unsigned int len)
309 const char **gp;
311 if (gpaths && (len <= gpaths->maxlen))
312 for (gp = gpaths->searchpath; *gp != NULL; ++gp)
313 if (strneq (*gp, file, len) && (*gp)[len] == '\0')
314 return 1;
316 return 0;
320 /* Search the given VPATH list for a directory where the name pointed to by
321 FILE exists. If it is found, we return a cached name of the existing file
322 and set *MTIME_PTR (if MTIME_PTR is not NULL) to its modtime (or zero if no
323 stat call was done). Otherwise we return NULL. */
325 static const char *
326 selective_vpath_search (struct vpath *path, const char *file,
327 FILE_TIMESTAMP *mtime_ptr)
329 int not_target;
330 char *name;
331 const char *n;
332 const char *filename;
333 const char **vpath = path->searchpath;
334 unsigned int maxvpath = path->maxlen;
335 unsigned int i;
336 unsigned int flen, vlen, name_dplen;
337 int exists = 0;
339 /* Find out if *FILE is a target.
340 If and only if it is NOT a target, we will accept prospective
341 files that don't exist but are mentioned in a makefile. */
343 struct file *f = lookup_file (file);
344 not_target = f == 0 || !f->is_target;
347 flen = strlen (file);
349 /* Split *FILE into a directory prefix and a name-within-directory.
350 NAME_DPLEN gets the length of the prefix; FILENAME gets the pointer to
351 the name-within-directory and FLEN is its length. */
353 n = strrchr (file, '/');
354 #ifdef HAVE_DOS_PATHS
355 /* We need the rightmost slash or backslash. */
357 const char *bslash = strrchr(file, '\\');
358 if (!n || bslash > n)
359 n = bslash;
361 #endif
362 name_dplen = n != 0 ? n - file : 0;
363 filename = name_dplen > 0 ? n + 1 : file;
364 if (name_dplen > 0)
365 flen -= name_dplen + 1;
367 /* Get enough space for the biggest VPATH entry, a slash, the directory
368 prefix that came with FILE, another slash (although this one may not
369 always be necessary), the filename, and a null terminator. */
370 name = alloca (maxvpath + 1 + name_dplen + 1 + flen + 1);
372 /* Try each VPATH entry. */
373 for (i = 0; vpath[i] != 0; ++i)
375 int exists_in_cache = 0;
376 char *p;
378 p = name;
380 /* Put the next VPATH entry into NAME at P and increment P past it. */
381 vlen = strlen (vpath[i]);
382 memcpy (p, vpath[i], vlen);
383 p += vlen;
385 /* Add the directory prefix already in *FILE. */
386 if (name_dplen > 0)
388 #ifndef VMS
389 *p++ = '/';
390 #endif
391 memcpy (p, file, name_dplen);
392 p += name_dplen;
395 #ifdef HAVE_DOS_PATHS
396 /* Cause the next if to treat backslash and slash alike. */
397 if (p != name && p[-1] == '\\' )
398 p[-1] = '/';
399 #endif
400 /* Now add the name-within-directory at the end of NAME. */
401 #ifndef VMS
402 if (p != name && p[-1] != '/')
404 *p = '/';
405 memcpy (p + 1, filename, flen + 1);
407 else
408 #endif
409 memcpy (p, filename, flen + 1);
411 /* Check if the file is mentioned in a makefile. If *FILE is not
412 a target, that is enough for us to decide this file exists.
413 If *FILE is a target, then the file must be mentioned in the
414 makefile also as a target to be chosen.
416 The restriction that *FILE must not be a target for a
417 makefile-mentioned file to be chosen was added by an
418 inadequately commented change in July 1990; I am not sure off
419 hand what problem it fixes.
421 In December 1993 I loosened this restriction to allow a file
422 to be chosen if it is mentioned as a target in a makefile. This
423 seem logical.
425 Special handling for -W / -o: make sure we preserve the special
426 values here. Actually this whole thing is a little bogus: I think
427 we should ditch the name/hname thing and look into the renamed
428 capability that already exists for files: that is, have a new struct
429 file* entry for the VPATH-found file, and set the renamed field if
430 we use it.
433 struct file *f = lookup_file (name);
434 if (f != 0)
436 exists = not_target || f->is_target;
437 if (exists && mtime_ptr
438 && (f->last_mtime == OLD_MTIME || f->last_mtime == NEW_MTIME))
440 *mtime_ptr = f->last_mtime;
441 mtime_ptr = 0;
446 if (!exists)
448 /* That file wasn't mentioned in the makefile.
449 See if it actually exists. */
451 #ifdef VMS
452 exists_in_cache = exists = dir_file_exists_p (vpath[i], filename);
453 #else
454 /* Clobber a null into the name at the last slash.
455 Now NAME is the name of the directory to look in. */
456 *p = '\0';
458 /* We know the directory is in the hash table now because either
459 construct_vpath_list or the code just above put it there.
460 Does the file we seek exist in it? */
461 exists_in_cache = exists = dir_file_exists_p (name, filename);
462 #endif
465 if (exists)
467 /* The file is in the directory cache.
468 Now check that it actually exists in the filesystem.
469 The cache may be out of date. When vpath thinks a file
470 exists, but stat fails for it, confusion results in the
471 higher levels. */
473 struct stat st;
475 #ifndef VMS
476 /* Put the slash back in NAME. */
477 *p = '/';
478 #endif
480 if (exists_in_cache) /* Makefile-mentioned file need not exist. */
482 int e;
484 EINTRLOOP (e, stat (name, &st)); /* Does it really exist? */
485 if (e != 0)
487 exists = 0;
488 continue;
491 /* Store the modtime into *MTIME_PTR for the caller. */
492 if (mtime_ptr != 0)
494 *mtime_ptr = FILE_TIMESTAMP_STAT_MODTIME (name, st);
495 mtime_ptr = 0;
499 /* We have found a file.
500 If we get here and mtime_ptr hasn't been set, record
501 UNKNOWN_MTIME to indicate this. */
502 if (mtime_ptr != 0)
503 *mtime_ptr = UNKNOWN_MTIME;
505 /* Store the name we found and return it. */
507 return strcache_add_len (name, (p + 1 - name) + flen);
511 return 0;
515 /* Search the VPATH list whose pattern matches FILE for a directory where FILE
516 exists. If it is found, return the cached name of an existing file, and
517 set *MTIME_PTR (if MTIME_PTR is not NULL) to its modtime (or zero if no
518 stat call was done). Otherwise we return 0. */
520 const char *
521 vpath_search (const char *file, FILE_TIMESTAMP *mtime_ptr)
523 struct vpath *v;
525 /* If there are no VPATH entries or FILENAME starts at the root,
526 there is nothing we can do. */
528 if (file[0] == '/'
529 #ifdef HAVE_DOS_PATHS
530 || file[0] == '\\' || file[1] == ':'
531 #endif
532 || (vpaths == 0 && general_vpath == 0))
533 return 0;
535 for (v = vpaths; v != 0; v = v->next)
536 if (pattern_matches (v->pattern, v->percent, file))
538 const char *p = selective_vpath_search (v, file, mtime_ptr);
539 if (p)
540 return p;
543 if (general_vpath != 0)
545 const char *p = selective_vpath_search (general_vpath, file, mtime_ptr);
546 if (p)
547 return p;
550 return 0;
553 /* Print the data base of VPATH search paths. */
555 void
556 print_vpath_data_base (void)
558 unsigned int nvpaths;
559 struct vpath *v;
561 puts (_("\n# VPATH Search Paths\n"));
563 nvpaths = 0;
564 for (v = vpaths; v != 0; v = v->next)
566 register unsigned int i;
568 ++nvpaths;
570 printf ("vpath %s ", v->pattern);
572 for (i = 0; v->searchpath[i] != 0; ++i)
573 printf ("%s%c", v->searchpath[i],
574 v->searchpath[i + 1] == 0 ? '\n' : PATH_SEPARATOR_CHAR);
577 if (vpaths == 0)
578 puts (_("# No `vpath' search paths."));
579 else
580 printf (_("\n# %u `vpath' search paths.\n"), nvpaths);
582 if (general_vpath == 0)
583 puts (_("\n# No general (`VPATH' variable) search path."));
584 else
586 const char **path = general_vpath->searchpath;
587 unsigned int i;
589 fputs (_("\n# General (`VPATH' variable) search path:\n# "), stdout);
591 for (i = 0; path[i] != 0; ++i)
592 printf ("%s%c", path[i],
593 path[i + 1] == 0 ? '\n' : PATH_SEPARATOR_CHAR);