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 file_name_list *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 file_name_list *));
98 static struct file_name_list *actual_directory
99 PARAMS ((cpp_reader *, const char *));
100 static struct include_file *find_include_file
101 PARAMS ((cpp_reader *, const char *,
102 struct file_name_list *));
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.
179 Returns an include_file structure with an open file descriptor on
180 success, or NULL on failure. */
182 static struct include_file *
183 open_file (pfile, filename)
185 const char *filename;
188 struct include_file *file;
190 nd = splay_tree_lookup (pfile->all_include_files, (splay_tree_key) filename);
194 file = (struct include_file *) nd->value;
196 /* Don't retry opening if we failed previously. */
200 /* Don't reopen an idempotent file. */
201 if (DO_NOT_REREAD (file))
204 /* Don't reopen one which is already loaded. */
205 if (file->buffer != NULL)
210 /* In particular, this clears foundhere. */
211 file = xcnew (struct include_file);
212 file->name = xstrdup (filename);
213 splay_tree_insert (pfile->all_include_files,
214 (splay_tree_key) file->name,
215 (splay_tree_value) file);
218 /* We used to open files in nonblocking mode, but that caused more
219 problems than it solved. Do take care not to acquire a
220 controlling terminal by mistake (this can't happen on sane
221 systems, but paranoia is a virtue).
223 Use the three-argument form of open even though we aren't
224 specifying O_CREAT, to defend against broken system headers.
226 O_BINARY tells some runtime libraries (notably DJGPP) not to do
227 newline translation; we can handle DOS line breaks just fine
230 Special case: the empty string is translated to stdin. */
232 if (filename[0] == '\0')
235 file->fd = open (filename, O_RDONLY | O_NOCTTY | O_BINARY, 0666);
237 if (file->fd != -1 && fstat (file->fd, &file->st) == 0)
239 /* Mark a regular, zero-length file never-reread now. */
240 if (S_ISREG (file->st.st_mode) && file->st.st_size == 0)
242 _cpp_never_reread (file);
250 /* Don't issue an error message if the file doesn't exist. */
251 if (errno != ENOENT && errno != ENOTDIR)
252 cpp_error_from_errno (pfile, filename);
254 /* Create a negative node for this path, and return null. */
260 /* Place the file referenced by INC into a new buffer on PFILE's
261 stack. If there are errors, or the file should not be re-included,
262 a null buffer is pushed. */
265 stack_include_file (pfile, inc)
267 struct include_file *inc;
273 /* We'll try removing deps_sysp after the release of 3.0. */
274 deps_sysp = pfile->system_include_depth != 0;
275 sysp = ((pfile->buffer && pfile->buffer->sysp)
276 || (inc->foundhere && inc->foundhere->sysp));
278 /* For -M, add the file to the dependencies on its first inclusion. */
279 if (CPP_OPTION (pfile, print_deps) > deps_sysp && !inc->include_count)
280 deps_add_dep (pfile->deps, inc->name);
282 /* We don't want multiple include guard advice for the main file. */
284 inc->include_count++;
288 read_include_file (pfile, inc);
290 if (! DO_NOT_REREAD (inc))
291 len = inc->st.st_size;
294 fp = cpp_push_buffer (pfile, inc->buffer, len, BUF_FILE, inc->name);
299 /* The ->actual_dir field is only used when ignore_srcdir is not in effect;
301 if (!CPP_OPTION (pfile, ignore_srcdir))
302 fp->actual_dir = actual_directory (pfile, inc->name);
304 /* Initialise controlling macro state. */
305 pfile->mi_state = MI_OUTSIDE;
306 pfile->mi_cmacro = 0;
307 pfile->include_depth++;
309 /* Generate the call back. */
311 _cpp_do_file_change (pfile, FC_ENTER, 0, 0);
315 /* Read the file referenced by INC into the file cache.
317 If fd points to a plain file, we might be able to mmap it; we can
318 definitely allocate the buffer all at once. If fd is a pipe or
319 terminal, we can't do either. If fd is something weird, like a
320 block device or a directory, we don't want to read it at all.
322 Unfortunately, different systems use different st.st_mode values
323 for pipes: some have S_ISFIFO, some S_ISSOCK, some are buggy and
324 zero the entire struct stat except a couple fields. Hence we don't
325 even try to figure out what something is, except for plain files,
326 directories, and block devices.
328 FIXME: Flush file cache and try again if we run out of memory. */
331 read_include_file (pfile, inc)
333 struct include_file *inc;
335 ssize_t size, offset, count;
338 static int pagesize = -1;
341 if (DO_NOT_REREAD (inc))
344 if (S_ISREG (inc->st.st_mode))
346 /* off_t might have a wider range than ssize_t - in other words,
347 the max size of a file might be bigger than the address
348 space. We can't handle a file that large. (Anyone with
349 a single source file bigger than 2GB needs to rethink
350 their coding style.) Some systems (e.g. AIX 4.1) define
351 SSIZE_MAX to be much smaller than the actual range of the
352 type. Use INTTYPE_MAXIMUM unconditionally to ensure this
354 if (inc->st.st_size > INTTYPE_MAXIMUM (ssize_t))
356 cpp_error (pfile, "%s is too large", inc->name);
359 size = inc->st.st_size;
364 pagesize = getpagesize ();
366 if (size / pagesize >= MMAP_THRESHOLD)
368 buf = (U_CHAR *) mmap (0, size, PROT_READ, MAP_PRIVATE, inc->fd, 0);
369 if (buf == (U_CHAR *)-1)
376 buf = (U_CHAR *) xmalloc (size);
378 while (offset < size)
380 count = read (inc->fd, buf + offset, size - offset);
385 cpp_warning (pfile, "%s is shorter than expected", inc->name);
392 else if (S_ISBLK (inc->st.st_mode))
394 cpp_error (pfile, "%s is a block device", inc->name);
397 else if (S_ISDIR (inc->st.st_mode))
399 cpp_error (pfile, "%s is a directory", inc->name);
404 /* 8 kilobytes is a sensible starting size. It ought to be
405 bigger than the kernel pipe buffer, and it's definitely
406 bigger than the majority of C source files. */
409 buf = (U_CHAR *) xmalloc (size);
411 while ((count = read (inc->fd, buf + offset, size - offset)) > 0)
415 buf = xrealloc (buf, (size *= 2));
421 buf = xrealloc (buf, offset);
422 inc->st.st_size = offset;
431 cpp_error_from_errno (pfile, inc->name);
433 /* Do not try to read this file again. */
436 _cpp_never_reread (inc);
442 struct include_file *inc;
448 munmap ((PTR) inc->buffer, inc->st.st_size);
451 free ((PTR) inc->buffer);
456 /* Return 1 if the file named by FNAME has been included before in
457 any context, 0 otherwise. */
459 cpp_included (pfile, fname)
463 struct file_name_list *path;
467 if (IS_ABSOLUTE_PATHNAME (fname))
469 /* Just look it up. */
470 nd = splay_tree_lookup (pfile->all_include_files, (splay_tree_key) fname);
471 return (nd && nd->value);
474 /* Search directory path for the file. */
475 name = (char *) alloca (strlen (fname) + pfile->max_include_len
476 + 2 + INCLUDE_LEN_FUDGE);
477 for (path = CPP_OPTION (pfile, quote_include); path; path = path->next)
479 memcpy (name, path->name, path->nlen);
480 name[path->nlen] = '/';
481 strcpy (&name[path->nlen+1], fname);
482 _cpp_simplify_pathname (name);
483 if (CPP_OPTION (pfile, remap))
484 name = remap_filename (pfile, name, path);
486 nd = splay_tree_lookup (pfile->all_include_files, (splay_tree_key) name);
493 /* Search for include file FNAME in the include chain starting at
494 SEARCH_START. Return 0 if there is no such file (or it's un-openable),
495 otherwise an include_file structure. */
497 static struct include_file *
498 find_include_file (pfile, fname, search_start)
501 struct file_name_list *search_start;
503 struct file_name_list *path;
505 struct include_file *file;
507 if (IS_ABSOLUTE_PATHNAME (fname))
508 return open_file (pfile, fname);
510 /* Search directory path for the file. */
511 name = (char *) alloca (strlen (fname) + pfile->max_include_len
512 + 2 + INCLUDE_LEN_FUDGE);
513 for (path = search_start; path; path = path->next)
515 memcpy (name, path->name, path->nlen);
516 name[path->nlen] = '/';
517 strcpy (&name[path->nlen+1], fname);
518 _cpp_simplify_pathname (name);
519 if (CPP_OPTION (pfile, remap))
520 name = remap_filename (pfile, name, path);
522 file = open_file (pfile, name);
525 file->foundhere = path;
532 /* Not everyone who wants to set system-header-ness on a buffer can
533 see the details of a buffer. This is an exported interface because
534 fix-header needs it. */
536 cpp_make_system_header (pfile, syshdr, externc)
542 /* 1 = system header, 2 = system header to be treated as C. */
544 flags = 1 + (externc != 0);
545 pfile->buffer->sysp = flags;
546 _cpp_do_file_change (pfile, FC_RENAME, pfile->buffer->nominal_fname,
547 pfile->buffer->lineno);
550 /* Report on all files that might benefit from a multiple include guard.
553 _cpp_report_missing_guards (pfile)
557 splay_tree_foreach (pfile->all_include_files, report_missing_guard,
562 report_missing_guard (n, b)
566 struct include_file *f = (struct include_file *) n->value;
567 int *bannerp = (int *)b;
569 if (f && f->cmacro == 0 && f->include_count == 1)
573 fputs (_("Multiple include guards may be useful for:\n"), stderr);
576 fputs (f->name, stderr);
583 _cpp_execute_include (pfile, header, no_reinclude, include_next)
585 const cpp_token *header;
589 struct file_name_list *search_start = 0;
590 unsigned int len = header->val.str.len;
591 unsigned int angle_brackets = header->type == CPP_HEADER_NAME;
592 struct include_file *inc;
596 /* Help protect #include or similar from recursion. */
597 if (pfile->buffer_stack_depth >= CPP_STACK_MAX)
599 cpp_fatal (pfile, "#include nested too deeply");
603 /* Check we've tidied up #include before entering the buffer. */
604 if (pfile->context->prev)
606 cpp_ice (pfile, "attempt to push file buffer with contexts stacked");
610 /* For #include_next, skip in the search path past the dir in which
611 the current file was found. If this is the last directory in the
612 search path, don't include anything. If the current file was
613 specified with an absolute path, use the normal search logic. If
614 this is the primary source file, use the normal search logic and
615 generate a warning. */
618 if (! pfile->buffer->prev)
619 cpp_warning (pfile, "#include_next in primary source file");
622 if (pfile->buffer->inc->foundhere)
624 search_start = pfile->buffer->inc->foundhere->next;
631 fname = alloca (len + 1);
632 memcpy (fname, header->val.str.text, len);
638 search_start = CPP_OPTION (pfile, bracket_include);
639 else if (CPP_OPTION (pfile, ignore_srcdir))
640 search_start = CPP_OPTION (pfile, quote_include);
642 search_start = CPP_BUFFER (pfile)->actual_dir;
646 cpp_error (pfile, "No include path in which to find %s", fname);
651 inc = find_include_file (pfile, fname, search_start);
655 pfile->system_include_depth++;
657 stack_include_file (pfile, inc);
659 if (! DO_NOT_REREAD (inc))
662 _cpp_never_reread (inc);
664 /* Handle -H option. */
665 if (CPP_OPTION (pfile, print_include_names))
667 cpp_buffer *fp = CPP_BUFFER (pfile);
668 while ((fp = CPP_PREV_BUFFER (fp)) != NULL)
670 fprintf (stderr, " %s\n", inc->name);
677 /* We will try making the RHS pfile->buffer->sysp after 3.0. */
678 print_dep = CPP_PRINT_DEPS(pfile) > (angle_brackets
679 || pfile->system_include_depth);
680 if (CPP_OPTION (pfile, print_deps_missing_files) && print_dep)
682 if (!angle_brackets || IS_ABSOLUTE_PATHNAME (fname))
683 deps_add_dep (pfile->deps, fname);
687 struct file_name_list *ptr;
690 /* If requested as a system header, assume it belongs in
691 the first system header directory. */
692 if (CPP_OPTION (pfile, bracket_include))
693 ptr = CPP_OPTION (pfile, bracket_include);
695 ptr = CPP_OPTION (pfile, quote_include);
697 len = strlen (ptr->name);
698 p = (char *) alloca (len + strlen (fname) + 2);
701 memcpy (p, ptr->name, len);
704 strcpy (p + len, fname);
705 _cpp_simplify_pathname (p);
706 deps_add_dep (pfile->deps, p);
709 /* If -M was specified, and this header file won't be added to
710 the dependency list, then don't count this as an error,
711 because we can still produce correct output. Otherwise, we
712 can't produce correct output, because there may be
713 dependencies we need inside the missing file, and we don't
714 know what directory this missing file exists in. */
715 else if (CPP_PRINT_DEPS (pfile) && ! print_dep)
716 cpp_warning (pfile, "No include path in which to find %s", fname);
718 cpp_error_from_errno (pfile, fname);
721 /* Locate file F, and determine whether it is newer than PFILE. Return -1,
722 if F cannot be located or dated, 1, if it is newer and 0 if older. */
724 _cpp_compare_file_date (pfile, f)
728 unsigned int len = f->val.str.len;
730 struct file_name_list *search_start;
731 struct include_file *inc;
733 if (f->type == CPP_HEADER_NAME)
734 search_start = CPP_OPTION (pfile, bracket_include);
735 else if (CPP_OPTION (pfile, ignore_srcdir))
736 search_start = CPP_OPTION (pfile, quote_include);
738 search_start = CPP_BUFFER (pfile)->actual_dir;
740 fname = alloca (len + 1);
741 memcpy (fname, f->val.str.text, len);
743 inc = find_include_file (pfile, fname, search_start);
753 return inc->st.st_mtime > CPP_BUFFER (pfile)->inc->st.st_mtime;
757 /* Push an input buffer and load it up with the contents of FNAME.
758 If FNAME is "" or NULL, read standard input. */
760 _cpp_read_file (pfile, fname)
764 struct include_file *f;
769 f = open_file (pfile, fname);
773 cpp_error_from_errno (pfile, fname);
777 stack_include_file (pfile, f);
781 /* Do appropriate cleanup when a file buffer is popped off the input
784 _cpp_pop_file_buffer (pfile, buf)
788 struct include_file *inc = buf->inc;
790 if (pfile->system_include_depth)
791 pfile->system_include_depth--;
792 if (pfile->include_depth)
793 pfile->include_depth--;
795 /* Record the inclusion-preventing macro and its definedness. */
796 if (pfile->mi_state == MI_OUTSIDE && inc->cmacro != NEVER_REREAD)
798 /* This could be NULL meaning no controlling macro. */
799 inc->cmacro = pfile->mi_cmacro;
803 /* Invalidate control macros in the #including file. */
804 pfile->mi_state = MI_FAILED;
807 if (inc->refcnt == 0 && DO_NOT_REREAD (inc))
811 /* The file_name_map structure holds a mapping of file names for a
812 particular directory. This mapping is read from the file named
813 FILE_NAME_MAP_FILE in that directory. Such a file can be used to
814 map filenames on a file system with severe filename restrictions,
815 such as DOS. The format of the file name map file is just a series
816 of lines with two tokens on each line. The first token is the name
817 to map, and the second token is the actual name to use. */
821 struct file_name_map *map_next;
826 #define FILE_NAME_MAP_FILE "header.gcc"
828 /* Read a space delimited string of unlimited length from a stdio
832 read_filename_string (ch, f)
840 set = alloc = xmalloc (len + 1);
844 while ((ch = getc (f)) != EOF && ! is_space(ch))
846 if (set - alloc == len)
849 alloc = xrealloc (alloc, len + 1);
850 set = alloc + len / 2;
860 /* This structure holds a linked list of file name maps, one per directory. */
862 struct file_name_map_list
864 struct file_name_map_list *map_list_next;
866 struct file_name_map *map_list_map;
869 /* Read the file name map file for DIRNAME. */
871 static struct file_name_map *
872 read_name_map (pfile, dirname)
876 register struct file_name_map_list *map_list_ptr;
880 /* Check the cache of directories, and mappings in their remap file. */
881 for (map_list_ptr = CPP_OPTION (pfile, map_list); map_list_ptr;
882 map_list_ptr = map_list_ptr->map_list_next)
883 if (! strcmp (map_list_ptr->map_list_name, dirname))
884 return map_list_ptr->map_list_map;
886 map_list_ptr = ((struct file_name_map_list *)
887 xmalloc (sizeof (struct file_name_map_list)));
888 map_list_ptr->map_list_name = xstrdup (dirname);
890 /* The end of the list ends in NULL. */
891 map_list_ptr->map_list_map = NULL;
893 name = (char *) alloca (strlen (dirname) + strlen (FILE_NAME_MAP_FILE) + 2);
894 strcpy (name, dirname);
897 strcat (name, FILE_NAME_MAP_FILE);
898 f = fopen (name, "r");
900 /* Silently return NULL if we cannot open. */
904 int dirlen = strlen (dirname);
906 while ((ch = getc (f)) != EOF)
909 struct file_name_map *ptr;
913 from = read_filename_string (ch, f);
914 while ((ch = getc (f)) != EOF && is_hspace(ch))
916 to = read_filename_string (ch, f);
918 ptr = ((struct file_name_map *)
919 xmalloc (sizeof (struct file_name_map)));
920 ptr->map_from = from;
922 /* Make the real filename absolute. */
923 if (IS_ABSOLUTE_PATHNAME (to))
927 ptr->map_to = xmalloc (dirlen + strlen (to) + 2);
928 strcpy (ptr->map_to, dirname);
929 ptr->map_to[dirlen] = '/';
930 strcpy (ptr->map_to + dirlen + 1, to);
934 ptr->map_next = map_list_ptr->map_list_map;
935 map_list_ptr->map_list_map = ptr;
937 while ((ch = getc (f)) != '\n')
944 /* Add this information to the cache. */
945 map_list_ptr->map_list_next = CPP_OPTION (pfile, map_list);
946 CPP_OPTION (pfile, map_list) = map_list_ptr;
948 return map_list_ptr->map_list_map;
951 /* Remap NAME based on the file_name_map (if any) for LOC. */
954 remap_filename (pfile, name, loc)
957 struct file_name_list *loc;
959 struct file_name_map *map;
960 const char *from, *p;
965 loc->name_map = read_name_map (pfile, loc->name ? loc->name : ".");
970 from = name + strlen (loc->name) + 1;
972 for (map = loc->name_map; map; map = map->map_next)
973 if (!strcmp (map->map_from, from))
976 /* Try to find a mapping file for the particular directory we are
977 looking in. Thus #include <sys/types.h> will look up sys/types.h
978 in /usr/include/header.gcc and look up types.h in
979 /usr/include/sys/header.gcc. */
980 p = strrchr (name, '/');
984 /* We know p != name as absolute paths don't call remap_filename. */
986 cpp_ice (pfile, "absolute file name in remap_filename");
988 dir = (char *) alloca (p - name + 1);
989 memcpy (dir, name, p - name);
990 dir[p - name] = '\0';
993 for (map = read_name_map (pfile, dir); map; map = map->map_next)
994 if (! strcmp (map->map_from, from))
1000 /* Given a path FNAME, extract the directory component and place it
1001 onto the actual_dirs list. Return a pointer to the allocated
1002 file_name_list structure. These structures are used to implement
1003 current-directory "" include searching. */
1005 static struct file_name_list *
1006 actual_directory (pfile, fname)
1010 char *last_slash, *dir;
1012 struct file_name_list *x;
1014 dir = xstrdup (fname);
1015 last_slash = strrchr (dir, '/');
1018 if (last_slash == dir)
1021 last_slash[1] = '\0';
1025 dlen = last_slash - dir;
1032 dir = xstrdup (".");
1036 if (dlen > pfile->max_include_len)
1037 pfile->max_include_len = dlen;
1039 for (x = pfile->actual_dirs; x; x = x->alloc)
1040 if (!strcmp (x->name, dir))
1046 /* Not found, make a new one. */
1047 x = (struct file_name_list *) xmalloc (sizeof (struct file_name_list));
1050 x->next = CPP_OPTION (pfile, quote_include);
1051 x->alloc = pfile->actual_dirs;
1052 x->sysp = pfile->buffer->sysp;
1055 pfile->actual_dirs = x;
1059 /* Simplify a path name in place, deleting redundant components. This
1060 reduces OS overhead and guarantees that equivalent paths compare
1061 the same (modulo symlinks).
1064 foo/bar/../quux foo/quux
1068 //quux //quux (POSIX allows leading // as a namespace escape)
1070 Guarantees no trailing slashes. All transforms reduce the length
1074 _cpp_simplify_pathname (path)
1081 #if defined (HAVE_DOS_BASED_FILE_SYSTEM)
1082 /* Convert all backslashes to slashes. */
1083 for (from = path; *from; from++)
1084 if (*from == '\\') *from = '/';
1086 /* Skip over leading drive letter if present. */
1087 if (ISALPHA (path[0]) && path[1] == ':')
1088 from = to = &path[2];
1095 /* Remove redundant initial /s. */
1104 /* 3 or more initial /s are equivalent to 1 /. */
1105 while (*++from == '/');
1107 /* On some hosts // differs from /; Posix allows this. */
1115 while (*from == '/')
1118 if (from[0] == '.' && from[1] == '/')
1120 else if (from[0] == '.' && from[1] == '\0')
1122 else if (from[0] == '.' && from[1] == '.' && from[2] == '/')
1139 while (to > base && *to != '/') to--;
1145 else if (from[0] == '.' && from[1] == '.' && from[2] == '\0')
1158 while (to > base && *to != '/') to--;
1165 /* Copy this component and trailing /, if any. */
1166 while ((*to++ = *from++) != '/')
1178 /* Trim trailing slash */
1179 if (to[0] == '/' && (!absolute || to > path+1))
1182 /* Change the empty string to "." so that stat() on the result
1183 will always work. */