1 /* Part of CPP library. (include file handling)
2 Copyright (C) 1986, 1987, 1989, 1992, 1993, 1994, 1995, 1998,
3 1999, 2000, 2001 Free Software Foundation, Inc.
4 Written by Per Bothner, 1994.
5 Based on CCCP program by Paul Rubin, June 1986
6 Adapted to ANSI C, Richard Stallman, Jan 1987
7 Split out of cpplib.c, Zack Weinberg, Oct 1998
9 This program is free software; you can redistribute it and/or modify it
10 under the terms of the GNU General Public License as published by the
11 Free Software Foundation; either version 2, or (at your option) any
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
29 #include "splay-tree.h"
32 # include <sys/mman.h>
33 # ifndef MMAP_THRESHOLD
34 # define MMAP_THRESHOLD 3 /* Minimum page count to mmap the file. */
37 #else /* No MMAP_FILE */
38 # undef MMAP_THRESHOLD
39 # define MMAP_THRESHOLD 0
46 #ifndef INCLUDE_LEN_FUDGE
47 # define INCLUDE_LEN_FUDGE 0
50 /* If errno is inspected immediately after a system call fails, it will be
51 nonzero, and no error number will ever be zero. */
62 /* Suppress warning about function macros used w/o arguments in traditional
63 C. It is unlikely that glibc's strcmp macro helps this file at all. */
66 /* This structure is used for the table of all includes. */
69 const char *name; /* actual path name of file */
70 const cpp_hashnode *cmacro; /* macro, if any, preventing reinclusion. */
71 const struct search_path *foundhere;
72 /* location in search path where file was
73 found, for #include_next and sysp. */
74 const unsigned char *buffer; /* pointer to cached file contents */
75 struct stat st; /* copy of stat(2) data for file */
76 int fd; /* fd open on file (short term storage only) */
77 unsigned short include_count; /* number of times file has been read */
78 unsigned short refcnt; /* number of stacked buffers using this file */
79 unsigned char mapped; /* file buffer is mmapped */
80 unsigned char defined; /* cmacro prevents inclusion in this state */
83 /* The cmacro works like this: If it's NULL, the file is to be
84 included again. If it's NEVER_REREAD, the file is never to be
85 included again. Otherwise it is a macro hashnode, and the file is
86 to be included again if the macro is defined or not as specified by
88 #define NEVER_REREAD ((const cpp_hashnode *)-1)
89 #define DO_NOT_REREAD(inc) \
90 ((inc)->cmacro && ((inc)->cmacro == NEVER_REREAD \
91 || ((inc)->cmacro->type == NT_MACRO) == (inc)->defined))
93 static struct file_name_map *read_name_map
94 PARAMS ((cpp_reader *, const char *));
95 static char *read_filename_string PARAMS ((int, FILE *));
96 static char *remap_filename PARAMS ((cpp_reader *, char *,
97 struct search_path *));
98 static struct search_path *search_from PARAMS ((cpp_reader *,
99 struct include_file *));
100 static struct include_file *find_include_file
101 PARAMS ((cpp_reader *, const char *,
102 struct search_path *));
103 static struct include_file *open_file PARAMS ((cpp_reader *, const char *));
104 static void read_include_file PARAMS ((cpp_reader *, struct include_file *));
105 static void stack_include_file PARAMS ((cpp_reader *, struct include_file *));
106 static void purge_cache PARAMS ((struct include_file *));
107 static void destroy_include_file_node PARAMS ((splay_tree_value));
108 static int report_missing_guard PARAMS ((splay_tree_node, void *));
110 /* We use a splay tree to store information about all the include
111 files seen in this compilation. The key of each tree node is the
112 physical path to the file. The value is 0 if the file does not
113 exist, or a struct include_file pointer. */
116 destroy_include_file_node (v)
119 struct include_file *f = (struct include_file *)v;
124 free (f); /* The tree is registered with free to free f->name. */
129 _cpp_init_includes (pfile)
132 pfile->all_include_files
133 = splay_tree_new ((splay_tree_compare_fn) strcmp,
134 (splay_tree_delete_key_fn) free,
135 destroy_include_file_node);
139 _cpp_cleanup_includes (pfile)
142 splay_tree_delete (pfile->all_include_files);
145 /* Mark a file to not be reread (e.g. #import, read failure). */
147 _cpp_never_reread (file)
148 struct include_file *file;
150 file->cmacro = NEVER_REREAD;
153 /* Put a file name in the splay tree, for the sake of cpp_included ().
154 Assume that FNAME has already had its path simplified. */
156 _cpp_fake_include (pfile, fname)
162 nd = splay_tree_lookup (pfile->all_include_files, (splay_tree_key) fname);
165 struct include_file *file = xcnew (struct include_file);
166 file->name = xstrdup (fname);
167 splay_tree_insert (pfile->all_include_files,
168 (splay_tree_key) file->name,
169 (splay_tree_value) file);
173 /* Given a file name, look it up in the cache; if there is no entry,
174 create one with a non-NULL value (regardless of success in opening
175 the file). If the file doesn't exist or is inaccessible, this
176 entry is flagged so we don't attempt to open it again in the
177 future. If the file isn't open, open it. The empty string is
178 interpreted as stdin.
180 Returns an include_file structure with an open file descriptor on
181 success, or NULL on failure. */
183 static struct include_file *
184 open_file (pfile, filename)
186 const char *filename;
189 struct include_file *file;
191 nd = splay_tree_lookup (pfile->all_include_files, (splay_tree_key) filename);
195 file = (struct include_file *) nd->value;
197 /* Don't retry opening if we failed previously. */
201 /* Don't reopen an idempotent file. */
202 if (DO_NOT_REREAD (file))
205 /* Don't reopen one which is already loaded. */
206 if (file->buffer != NULL)
211 /* In particular, this clears foundhere. */
212 file = xcnew (struct include_file);
213 file->name = xstrdup (filename);
214 splay_tree_insert (pfile->all_include_files,
215 (splay_tree_key) file->name,
216 (splay_tree_value) file);
219 /* We used to open files in nonblocking mode, but that caused more
220 problems than it solved. Do take care not to acquire a
221 controlling terminal by mistake (this can't happen on sane
222 systems, but paranoia is a virtue).
224 Use the three-argument form of open even though we aren't
225 specifying O_CREAT, to defend against broken system headers.
227 O_BINARY tells some runtime libraries (notably DJGPP) not to do
228 newline translation; we can handle DOS line breaks just fine
231 Special case: the empty string is translated to stdin. */
233 if (filename[0] == '\0')
236 file->fd = open (filename, O_RDONLY | O_NOCTTY | O_BINARY, 0666);
238 if (file->fd != -1 && fstat (file->fd, &file->st) == 0)
240 /* Mark a regular, zero-length file never-reread now. */
241 if (S_ISREG (file->st.st_mode) && file->st.st_size == 0)
243 _cpp_never_reread (file);
251 /* Don't issue an error message if the file doesn't exist. */
252 if (errno != ENOENT && errno != ENOTDIR)
253 cpp_error_from_errno (pfile, filename);
255 /* Create a negative node for this path, and return null. */
261 /* Place the file referenced by INC into a new buffer on PFILE's
262 stack. If there are errors, or the file should not be re-included,
263 a null buffer is pushed. */
266 stack_include_file (pfile, inc)
268 struct include_file *inc;
274 /* We'll try removing deps_sysp after the release of 3.0. */
275 deps_sysp = pfile->system_include_depth != 0;
276 sysp = ((pfile->buffer && pfile->buffer->sysp)
277 || (inc->foundhere && inc->foundhere->sysp));
279 /* For -M, add the file to the dependencies on its first inclusion. */
280 if (CPP_OPTION (pfile, print_deps) > deps_sysp && !inc->include_count)
281 deps_add_dep (pfile->deps, inc->name);
283 /* We don't want multiple include guard advice for the main file. */
285 inc->include_count++;
289 read_include_file (pfile, inc);
291 if (! DO_NOT_REREAD (inc))
292 len = inc->st.st_size;
295 fp = cpp_push_buffer (pfile, inc->buffer, len, BUF_FILE, inc->name);
299 fp->search_from = search_from (pfile, inc);
301 /* Initialise controlling macro state. */
302 pfile->mi_state = MI_OUTSIDE;
303 pfile->mi_cmacro = 0;
304 pfile->include_depth++;
306 /* Generate the call back. */
308 _cpp_do_file_change (pfile, FC_ENTER, 0, 0);
312 /* Read the file referenced by INC into the file cache.
314 If fd points to a plain file, we might be able to mmap it; we can
315 definitely allocate the buffer all at once. If fd is a pipe or
316 terminal, we can't do either. If fd is something weird, like a
317 block device or a directory, we don't want to read it at all.
319 Unfortunately, different systems use different st.st_mode values
320 for pipes: some have S_ISFIFO, some S_ISSOCK, some are buggy and
321 zero the entire struct stat except a couple fields. Hence we don't
322 even try to figure out what something is, except for plain files,
323 directories, and block devices.
325 FIXME: Flush file cache and try again if we run out of memory. */
328 read_include_file (pfile, inc)
330 struct include_file *inc;
332 ssize_t size, offset, count;
335 static int pagesize = -1;
338 if (DO_NOT_REREAD (inc))
341 if (S_ISREG (inc->st.st_mode))
343 /* off_t might have a wider range than ssize_t - in other words,
344 the max size of a file might be bigger than the address
345 space. We can't handle a file that large. (Anyone with
346 a single source file bigger than 2GB needs to rethink
347 their coding style.) Some systems (e.g. AIX 4.1) define
348 SSIZE_MAX to be much smaller than the actual range of the
349 type. Use INTTYPE_MAXIMUM unconditionally to ensure this
351 if (inc->st.st_size > INTTYPE_MAXIMUM (ssize_t))
353 cpp_error (pfile, "%s is too large", inc->name);
356 size = inc->st.st_size;
361 pagesize = getpagesize ();
363 if (size / pagesize >= MMAP_THRESHOLD)
365 buf = (U_CHAR *) mmap (0, size, PROT_READ, MAP_PRIVATE, inc->fd, 0);
366 if (buf == (U_CHAR *)-1)
373 buf = (U_CHAR *) xmalloc (size);
375 while (offset < size)
377 count = read (inc->fd, buf + offset, size - offset);
382 cpp_warning (pfile, "%s is shorter than expected", inc->name);
389 else if (S_ISBLK (inc->st.st_mode))
391 cpp_error (pfile, "%s is a block device", inc->name);
394 else if (S_ISDIR (inc->st.st_mode))
396 cpp_error (pfile, "%s is a directory", inc->name);
401 /* 8 kilobytes is a sensible starting size. It ought to be
402 bigger than the kernel pipe buffer, and it's definitely
403 bigger than the majority of C source files. */
406 buf = (U_CHAR *) xmalloc (size);
408 while ((count = read (inc->fd, buf + offset, size - offset)) > 0)
412 buf = xrealloc (buf, (size *= 2));
418 buf = xrealloc (buf, offset);
419 inc->st.st_size = offset;
428 cpp_error_from_errno (pfile, inc->name);
430 /* Do not try to read this file again. */
433 _cpp_never_reread (inc);
439 struct include_file *inc;
445 munmap ((PTR) inc->buffer, inc->st.st_size);
448 free ((PTR) inc->buffer);
453 /* Return 1 if the file named by FNAME has been included before in
454 any context, 0 otherwise. */
456 cpp_included (pfile, fname)
460 struct search_path *path;
464 if (IS_ABSOLUTE_PATHNAME (fname))
466 /* Just look it up. */
467 nd = splay_tree_lookup (pfile->all_include_files, (splay_tree_key) fname);
468 return (nd && nd->value);
471 /* Search directory path for the file. */
472 name = (char *) alloca (strlen (fname) + pfile->max_include_len
473 + 2 + INCLUDE_LEN_FUDGE);
474 for (path = CPP_OPTION (pfile, quote_include); path; path = path->next)
476 memcpy (name, path->name, path->len);
477 name[path->len] = '/';
478 strcpy (&name[path->len + 1], fname);
479 _cpp_simplify_pathname (name);
480 if (CPP_OPTION (pfile, remap))
481 name = remap_filename (pfile, name, path);
483 nd = splay_tree_lookup (pfile->all_include_files, (splay_tree_key) name);
490 /* Search for include file FNAME in the include chain starting at
491 SEARCH_START. Return 0 if there is no such file (or it's un-openable),
492 otherwise an include_file structure. */
494 static struct include_file *
495 find_include_file (pfile, fname, search_start)
498 struct search_path *search_start;
500 struct search_path *path;
502 struct include_file *file;
504 if (IS_ABSOLUTE_PATHNAME (fname))
505 return open_file (pfile, fname);
507 /* Search directory path for the file. */
508 name = (char *) alloca (strlen (fname) + pfile->max_include_len
509 + 2 + INCLUDE_LEN_FUDGE);
510 for (path = search_start; path; path = path->next)
512 memcpy (name, path->name, path->len);
513 name[path->len] = '/';
514 strcpy (&name[path->len + 1], fname);
515 _cpp_simplify_pathname (name);
516 if (CPP_OPTION (pfile, remap))
517 name = remap_filename (pfile, name, path);
519 file = open_file (pfile, name);
522 file->foundhere = path;
530 /* Not everyone who wants to set system-header-ness on a buffer can
531 see the details of a buffer. This is an exported interface because
532 fix-header needs it. */
534 cpp_make_system_header (pfile, syshdr, externc)
540 /* 1 = system header, 2 = system header to be treated as C. */
542 flags = 1 + (externc != 0);
543 pfile->buffer->sysp = flags;
544 _cpp_do_file_change (pfile, FC_RENAME, pfile->buffer->nominal_fname,
545 pfile->buffer->lineno);
548 /* Report on all files that might benefit from a multiple include guard.
551 _cpp_report_missing_guards (pfile)
555 splay_tree_foreach (pfile->all_include_files, report_missing_guard,
560 report_missing_guard (n, b)
564 struct include_file *f = (struct include_file *) n->value;
565 int *bannerp = (int *)b;
567 if (f && f->cmacro == 0 && f->include_count == 1)
571 fputs (_("Multiple include guards may be useful for:\n"), stderr);
574 fputs (f->name, stderr);
581 _cpp_execute_include (pfile, header, no_reinclude, include_next)
583 const cpp_token *header;
587 struct search_path *search_start = 0;
588 unsigned int angle_brackets = header->type == CPP_HEADER_NAME;
589 const char *fname = (const char *) header->val.str.text;
590 struct include_file *inc;
593 /* Help protect #include or similar from recursion. */
594 if (pfile->buffer_stack_depth >= CPP_STACK_MAX)
596 cpp_fatal (pfile, "#include nested too deeply");
600 /* Check we've tidied up #include before entering the buffer. */
601 if (pfile->context->prev)
603 cpp_ice (pfile, "attempt to push file buffer with contexts stacked");
607 /* For #include_next, skip in the search path past the dir in which
608 the current file was found. If this is the last directory in the
609 search path, don't include anything. If the current file was
610 specified with an absolute path, use the normal search logic. If
611 this is the primary source file, use the normal search logic and
612 generate a warning. */
615 if (! pfile->buffer->prev)
616 cpp_warning (pfile, "#include_next in primary source file");
619 if (pfile->buffer->inc->foundhere)
621 search_start = pfile->buffer->inc->foundhere->next;
631 search_start = CPP_OPTION (pfile, bracket_include);
633 search_start = pfile->buffer->search_from;
637 cpp_error (pfile, "No include path in which to find %s", fname);
642 inc = find_include_file (pfile, fname, search_start);
646 pfile->system_include_depth++;
648 stack_include_file (pfile, inc);
650 if (! DO_NOT_REREAD (inc))
653 _cpp_never_reread (inc);
655 /* Handle -H option. */
656 if (CPP_OPTION (pfile, print_include_names))
658 cpp_buffer *fp = pfile->buffer;
659 while ((fp = fp->prev) != NULL)
661 fprintf (stderr, " %s\n", inc->name);
668 /* We will try making the RHS pfile->buffer->sysp after 3.0. */
669 print_dep = CPP_PRINT_DEPS(pfile) > (angle_brackets
670 || pfile->system_include_depth);
671 if (CPP_OPTION (pfile, print_deps_missing_files) && print_dep)
673 if (!angle_brackets || IS_ABSOLUTE_PATHNAME (fname))
674 deps_add_dep (pfile->deps, fname);
678 struct search_path *ptr;
681 /* If requested as a system header, assume it belongs in
682 the first system header directory. */
683 if (CPP_OPTION (pfile, bracket_include))
684 ptr = CPP_OPTION (pfile, bracket_include);
686 ptr = CPP_OPTION (pfile, quote_include);
688 /* FIXME: ptr can be null, no? */
690 p = (char *) alloca (len + header->val.str.len + 2);
693 memcpy (p, ptr->name, len);
696 memcpy (p + len, fname, header->val.str.len + 1);
697 _cpp_simplify_pathname (p);
698 deps_add_dep (pfile->deps, p);
701 /* If -M was specified, and this header file won't be added to
702 the dependency list, then don't count this as an error,
703 because we can still produce correct output. Otherwise, we
704 can't produce correct output, because there may be
705 dependencies we need inside the missing file, and we don't
706 know what directory this missing file exists in. */
707 else if (CPP_PRINT_DEPS (pfile) && ! print_dep)
708 cpp_warning (pfile, "No include path in which to find %s", fname);
710 cpp_error_from_errno (pfile, fname);
713 /* Locate file F, and determine whether it is newer than PFILE. Return -1,
714 if F cannot be located or dated, 1, if it is newer and 0 if older. */
716 _cpp_compare_file_date (pfile, f)
720 const char *fname = (const char *) f->val.str.text;
721 struct search_path *search_start;
722 struct include_file *inc;
724 if (f->type == CPP_HEADER_NAME)
725 search_start = CPP_OPTION (pfile, bracket_include);
726 else if (CPP_OPTION (pfile, ignore_srcdir))
727 search_start = pfile->buffer->search_from;
729 inc = find_include_file (pfile, fname, search_start);
739 return inc->st.st_mtime > CPP_BUFFER (pfile)->inc->st.st_mtime;
743 /* Push an input buffer and load it up with the contents of FNAME.
744 If FNAME is "", read standard input. */
746 _cpp_read_file (pfile, fname)
750 struct include_file *f = open_file (pfile, fname);
754 cpp_error_from_errno (pfile, fname);
758 stack_include_file (pfile, f);
762 /* Do appropriate cleanup when a file buffer is popped off the input
765 _cpp_pop_file_buffer (pfile, buf)
769 struct include_file *inc = buf->inc;
771 if (pfile->system_include_depth)
772 pfile->system_include_depth--;
773 if (pfile->include_depth)
774 pfile->include_depth--;
776 /* Record the inclusion-preventing macro and its definedness. */
777 if (pfile->mi_state == MI_OUTSIDE && inc->cmacro != NEVER_REREAD)
779 /* This could be NULL meaning no controlling macro. */
780 inc->cmacro = pfile->mi_cmacro;
784 /* Invalidate control macros in the #including file. */
785 pfile->mi_state = MI_FAILED;
788 if (inc->refcnt == 0 && DO_NOT_REREAD (inc))
792 /* Returns the first place in the include chain to start searching for
793 "" includes. This involves stripping away the basename of the
794 current file, unless -I- was specified. */
795 static struct search_path *
796 search_from (pfile, inc)
798 struct include_file *inc;
800 cpp_buffer *buffer = pfile->buffer;
803 /* Ignore the current file's directory if -I- was given. */
804 if (CPP_OPTION (pfile, ignore_srcdir))
805 return CPP_OPTION (pfile, quote_include);
807 dlen = basename (inc->name) - inc->name;
810 /* We don't guarantee NAME is null-terminated. This saves
811 allocating and freeing memory, and duplicating it when faking
812 buffers in cpp_push_buffer. Drop a trailing '/'. */
813 buffer->dir.name = inc->name;
819 buffer->dir.name = ".";
823 if (dlen > pfile->max_include_len)
824 pfile->max_include_len = dlen;
826 buffer->dir.len = dlen;
827 buffer->dir.next = CPP_OPTION (pfile, quote_include);
828 buffer->dir.sysp = buffer->sysp;
833 /* The file_name_map structure holds a mapping of file names for a
834 particular directory. This mapping is read from the file named
835 FILE_NAME_MAP_FILE in that directory. Such a file can be used to
836 map filenames on a file system with severe filename restrictions,
837 such as DOS. The format of the file name map file is just a series
838 of lines with two tokens on each line. The first token is the name
839 to map, and the second token is the actual name to use. */
843 struct file_name_map *map_next;
848 #define FILE_NAME_MAP_FILE "header.gcc"
850 /* Read a space delimited string of unlimited length from a stdio
854 read_filename_string (ch, f)
862 set = alloc = xmalloc (len + 1);
866 while ((ch = getc (f)) != EOF && ! is_space(ch))
868 if (set - alloc == len)
871 alloc = xrealloc (alloc, len + 1);
872 set = alloc + len / 2;
882 /* This structure holds a linked list of file name maps, one per directory. */
884 struct file_name_map_list
886 struct file_name_map_list *map_list_next;
888 struct file_name_map *map_list_map;
891 /* Read the file name map file for DIRNAME. */
893 static struct file_name_map *
894 read_name_map (pfile, dirname)
898 register struct file_name_map_list *map_list_ptr;
902 /* Check the cache of directories, and mappings in their remap file. */
903 for (map_list_ptr = CPP_OPTION (pfile, map_list); map_list_ptr;
904 map_list_ptr = map_list_ptr->map_list_next)
905 if (! strcmp (map_list_ptr->map_list_name, dirname))
906 return map_list_ptr->map_list_map;
908 map_list_ptr = ((struct file_name_map_list *)
909 xmalloc (sizeof (struct file_name_map_list)));
910 map_list_ptr->map_list_name = xstrdup (dirname);
912 /* The end of the list ends in NULL. */
913 map_list_ptr->map_list_map = NULL;
915 name = (char *) alloca (strlen (dirname) + strlen (FILE_NAME_MAP_FILE) + 2);
916 strcpy (name, dirname);
919 strcat (name, FILE_NAME_MAP_FILE);
920 f = fopen (name, "r");
922 /* Silently return NULL if we cannot open. */
926 int dirlen = strlen (dirname);
928 while ((ch = getc (f)) != EOF)
931 struct file_name_map *ptr;
935 from = read_filename_string (ch, f);
936 while ((ch = getc (f)) != EOF && is_hspace(ch))
938 to = read_filename_string (ch, f);
940 ptr = ((struct file_name_map *)
941 xmalloc (sizeof (struct file_name_map)));
942 ptr->map_from = from;
944 /* Make the real filename absolute. */
945 if (IS_ABSOLUTE_PATHNAME (to))
949 ptr->map_to = xmalloc (dirlen + strlen (to) + 2);
950 strcpy (ptr->map_to, dirname);
951 ptr->map_to[dirlen] = '/';
952 strcpy (ptr->map_to + dirlen + 1, to);
956 ptr->map_next = map_list_ptr->map_list_map;
957 map_list_ptr->map_list_map = ptr;
959 while ((ch = getc (f)) != '\n')
966 /* Add this information to the cache. */
967 map_list_ptr->map_list_next = CPP_OPTION (pfile, map_list);
968 CPP_OPTION (pfile, map_list) = map_list_ptr;
970 return map_list_ptr->map_list_map;
973 /* Remap NAME based on the file_name_map (if any) for LOC. */
976 remap_filename (pfile, name, loc)
979 struct search_path *loc;
981 struct file_name_map *map;
982 const char *from, *p;
985 /* Get a null-terminated path. */
986 dname = alloca (loc->len + 1);
987 memcpy (dname, loc->name, loc->len);
988 dname[loc->len] = '\0';
992 loc->name_map = read_name_map (pfile, dname);
997 /* FIXME: this doesn't look right - NAME has been simplified. */
998 from = name + loc->len + 1;
1000 for (map = loc->name_map; map; map = map->map_next)
1001 if (!strcmp (map->map_from, from))
1004 /* Try to find a mapping file for the particular directory we are
1005 looking in. Thus #include <sys/types.h> will look up sys/types.h
1006 in /usr/include/header.gcc and look up types.h in
1007 /usr/include/sys/header.gcc. */
1008 p = strrchr (name, '/');
1012 /* We know p != name as absolute paths don't call remap_filename. */
1014 cpp_ice (pfile, "absolute file name in remap_filename");
1016 dir = (char *) alloca (p - name + 1);
1017 memcpy (dir, name, p - name);
1018 dir[p - name] = '\0';
1021 for (map = read_name_map (pfile, dir); map; map = map->map_next)
1022 if (! strcmp (map->map_from, from))
1028 /* Simplify a path name in place, deleting redundant components. This
1029 reduces OS overhead and guarantees that equivalent paths compare
1030 the same (modulo symlinks).
1033 foo/bar/../quux foo/quux
1037 //quux //quux (POSIX allows leading // as a namespace escape)
1039 Guarantees no trailing slashes. All transforms reduce the length
1043 _cpp_simplify_pathname (path)
1050 #if defined (HAVE_DOS_BASED_FILE_SYSTEM)
1051 /* Convert all backslashes to slashes. */
1052 for (from = path; *from; from++)
1053 if (*from == '\\') *from = '/';
1055 /* Skip over leading drive letter if present. */
1056 if (ISALPHA (path[0]) && path[1] == ':')
1057 from = to = &path[2];
1064 /* Remove redundant initial /s. */
1073 /* 3 or more initial /s are equivalent to 1 /. */
1074 while (*++from == '/');
1076 /* On some hosts // differs from /; Posix allows this. */
1084 while (*from == '/')
1087 if (from[0] == '.' && from[1] == '/')
1089 else if (from[0] == '.' && from[1] == '\0')
1091 else if (from[0] == '.' && from[1] == '.' && from[2] == '/')
1108 while (to > base && *to != '/') to--;
1114 else if (from[0] == '.' && from[1] == '.' && from[2] == '\0')
1127 while (to > base && *to != '/') to--;
1134 /* Copy this component and trailing /, if any. */
1135 while ((*to++ = *from++) != '/')
1147 /* Trim trailing slash */
1148 if (to[0] == '/' && (!absolute || to > path+1))
1151 /* Change the empty string to "." so that stat() on the result
1152 will always work. */