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 /* If errno is inspected immediately after a system call fails, it will be
47 nonzero, and no error number will ever be zero. */
55 /* Suppress warning about function macros used w/o arguments in traditional
56 C. It is unlikely that glibc's strcmp macro helps this file at all. */
59 /* This structure is used for the table of all includes. */
62 const char *name
; /* actual path name of file */
63 const cpp_hashnode
*cmacro
; /* macro, if any, preventing reinclusion. */
64 const struct search_path
*foundhere
;
65 /* location in search path where file was
66 found, for #include_next and sysp. */
67 const unsigned char *buffer
; /* pointer to cached file contents */
68 struct stat st
; /* copy of stat(2) data for file */
69 int fd
; /* fd open on file (short term storage only) */
70 int err_no
; /* errno obtained if opening a file failed */
71 unsigned short include_count
; /* number of times file has been read */
72 unsigned short refcnt
; /* number of stacked buffers using this file */
73 unsigned char mapped
; /* file buffer is mmapped */
76 /* The cmacro works like this: If it's NULL, the file is to be
77 included again. If it's NEVER_REREAD, the file is never to be
78 included again. Otherwise it is a macro hashnode, and the file is
79 to be included again if the macro is defined. */
80 #define NEVER_REREAD ((const cpp_hashnode *)-1)
81 #define DO_NOT_REREAD(inc) \
82 ((inc)->cmacro && ((inc)->cmacro == NEVER_REREAD \
83 || (inc)->cmacro->type == NT_MACRO))
84 #define NO_INCLUDE_PATH ((struct include_file *) -1)
86 static struct file_name_map
*read_name_map
87 PARAMS ((cpp_reader
*, const char *));
88 static char *read_filename_string
PARAMS ((int, FILE *));
89 static char *remap_filename
PARAMS ((cpp_reader
*, char *,
90 struct search_path
*));
91 static struct search_path
*search_from
PARAMS ((cpp_reader
*,
93 static struct include_file
*
94 find_include_file
PARAMS ((cpp_reader
*, const cpp_token
*,
96 static struct include_file
*open_file
PARAMS ((cpp_reader
*, const char *));
97 static int read_include_file
PARAMS ((cpp_reader
*, struct include_file
*));
98 static bool stack_include_file
PARAMS ((cpp_reader
*, struct include_file
*));
99 static void purge_cache
PARAMS ((struct include_file
*));
100 static void destroy_node
PARAMS ((splay_tree_value
));
101 static int report_missing_guard
PARAMS ((splay_tree_node
, void *));
102 static splay_tree_node find_or_create_entry
PARAMS ((cpp_reader
*,
104 static void handle_missing_header
PARAMS ((cpp_reader
*, const char *, int));
105 static int remove_component_p
PARAMS ((const char *));
107 /* Set up the splay tree we use to store information about all the
108 file names seen in this compilation. We also have entries for each
109 file we tried to open but failed; this saves system calls since we
110 don't try to open it again in future.
112 The key of each node is the file name, after processing by
113 _cpp_simplify_pathname. The path name may or may not be absolute.
114 The path string has been malloced, as is automatically freed by
115 registering free () as the splay tree key deletion function.
117 A node's value is a pointer to a struct include_file, and is never
120 _cpp_init_includes (pfile
)
123 pfile
->all_include_files
124 = splay_tree_new ((splay_tree_compare_fn
) strcmp
,
125 (splay_tree_delete_key_fn
) free
,
129 /* Tear down the splay tree. */
131 _cpp_cleanup_includes (pfile
)
134 splay_tree_delete (pfile
->all_include_files
);
137 /* Free a node. The path string is automatically freed. */
142 struct include_file
*f
= (struct include_file
*)v
;
151 /* Mark a file to not be reread (e.g. #import, read failure). */
153 _cpp_never_reread (file
)
154 struct include_file
*file
;
156 file
->cmacro
= NEVER_REREAD
;
159 /* Lookup a filename, which is simplified after making a copy, and
160 create an entry if none exists. errno is nonzero iff a (reported)
161 stat() error occurred during simplification. */
162 static splay_tree_node
163 find_or_create_entry (pfile
, fname
)
167 splay_tree_node node
;
168 struct include_file
*file
;
169 char *name
= xstrdup (fname
);
171 _cpp_simplify_pathname (name
);
172 node
= splay_tree_lookup (pfile
->all_include_files
, (splay_tree_key
) name
);
177 file
= xcnew (struct include_file
);
179 file
->err_no
= errno
;
180 node
= splay_tree_insert (pfile
->all_include_files
,
181 (splay_tree_key
) file
->name
,
182 (splay_tree_value
) file
);
188 /* Enter a file name in the splay tree, for the sake of cpp_included. */
190 _cpp_fake_include (pfile
, fname
)
194 find_or_create_entry (pfile
, fname
);
197 /* Given a file name, look it up in the cache; if there is no entry,
198 create one with a non-NULL value (regardless of success in opening
199 the file). If the file doesn't exist or is inaccessible, this
200 entry is flagged so we don't attempt to open it again in the
201 future. If the file isn't open, open it. The empty string is
202 interpreted as stdin.
204 Returns an include_file structure with an open file descriptor on
205 success, or NULL on failure. */
207 static struct include_file
*
208 open_file (pfile
, filename
)
210 const char *filename
;
212 splay_tree_node nd
= find_or_create_entry (pfile
, filename
);
213 struct include_file
*file
= (struct include_file
*) nd
->value
;
217 /* Ugh. handle_missing_header () needs errno to be set. */
218 errno
= file
->err_no
;
222 /* Don't reopen an idempotent file. */
223 if (DO_NOT_REREAD (file
))
226 /* Don't reopen one which is already loaded. */
227 if (file
->buffer
!= NULL
)
230 /* We used to open files in nonblocking mode, but that caused more
231 problems than it solved. Do take care not to acquire a
232 controlling terminal by mistake (this can't happen on sane
233 systems, but paranoia is a virtue).
235 Use the three-argument form of open even though we aren't
236 specifying O_CREAT, to defend against broken system headers.
238 O_BINARY tells some runtime libraries (notably DJGPP) not to do
239 newline translation; we can handle DOS line breaks just fine
242 Special case: the empty string is translated to stdin. */
244 if (filename
[0] == '\0')
247 file
->fd
= open (file
->name
, O_RDONLY
| O_NOCTTY
| O_BINARY
, 0666);
249 if (file
->fd
!= -1 && fstat (file
->fd
, &file
->st
) == 0)
251 /* If it's a directory, we return null and continue the search
252 as the file we're looking for may appear elsewhere in the
254 if (S_ISDIR (file
->st
.st_mode
))
258 /* Mark a regular, zero-length file never-reread now. */
259 if (S_ISREG (file
->st
.st_mode
) && file
->st
.st_size
== 0)
261 _cpp_never_reread (file
);
270 /* Don't issue an error message if the file doesn't exist. */
271 file
->err_no
= errno
;
272 if (errno
!= ENOENT
&& errno
!= ENOTDIR
)
273 cpp_error_from_errno (pfile
, file
->name
);
278 /* Place the file referenced by INC into a new buffer on the buffer
279 stack, unless there are errors, or the file is not re-included
280 because of e.g. multiple-include guards. Returns true if a buffer
284 stack_include_file (pfile
, inc
)
286 struct include_file
*inc
;
290 const char *filename
;
292 if (DO_NOT_REREAD (inc
))
295 sysp
= MAX ((pfile
->map
? pfile
->map
->sysp
: 0),
296 (inc
->foundhere
? inc
->foundhere
->sysp
: 0));
298 /* For -M, add the file to the dependencies on its first inclusion. */
299 if (CPP_OPTION (pfile
, print_deps
) > sysp
&& !inc
->include_count
)
300 deps_add_dep (pfile
->deps
, inc
->name
);
305 /* If an error occurs, do not try to read this file again. */
306 if (read_include_file (pfile
, inc
))
308 _cpp_never_reread (inc
);
317 /* We don't want MI guard advice for the main file. */
318 inc
->include_count
++;
320 /* Handle -H option. */
321 if (CPP_OPTION (pfile
, print_include_names
))
323 for (fp
= pfile
->buffer
; fp
; fp
= fp
->prev
)
325 fprintf (stderr
, " %s\n", inc
->name
);
330 fp
= cpp_push_buffer (pfile
, inc
->buffer
, inc
->st
.st_size
, BUF_FILE
, 0);
334 /* Initialise controlling macro state. */
335 pfile
->mi_valid
= true;
336 pfile
->mi_cmacro
= 0;
337 pfile
->include_depth
++;
339 /* Generate the call back. */
340 filename
= inc
->name
;
341 if (*filename
== '\0')
342 filename
= _("<stdin>");
343 _cpp_do_file_change (pfile
, LC_ENTER
, filename
, 1, sysp
);
348 /* Read the file referenced by INC into the file cache.
350 If fd points to a plain file, we might be able to mmap it; we can
351 definitely allocate the buffer all at once. If fd is a pipe or
352 terminal, we can't do either. If fd is something weird, like a
353 block device, we don't want to read it at all.
355 Unfortunately, different systems use different st.st_mode values
356 for pipes: some have S_ISFIFO, some S_ISSOCK, some are buggy and
357 zero the entire struct stat except a couple fields. Hence we don't
358 even try to figure out what something is, except for plain files
361 FIXME: Flush file cache and try again if we run out of memory. */
364 read_include_file (pfile
, inc
)
366 struct include_file
*inc
;
368 ssize_t size
, offset
, count
;
371 static int pagesize
= -1;
374 if (S_ISREG (inc
->st
.st_mode
))
376 /* off_t might have a wider range than ssize_t - in other words,
377 the max size of a file might be bigger than the address
378 space. We can't handle a file that large. (Anyone with
379 a single source file bigger than 2GB needs to rethink
380 their coding style.) Some systems (e.g. AIX 4.1) define
381 SSIZE_MAX to be much smaller than the actual range of the
382 type. Use INTTYPE_MAXIMUM unconditionally to ensure this
384 if (inc
->st
.st_size
> INTTYPE_MAXIMUM (ssize_t
))
386 cpp_error (pfile
, "%s is too large", inc
->name
);
389 size
= inc
->st
.st_size
;
394 pagesize
= getpagesize ();
396 if (size
/ pagesize
>= MMAP_THRESHOLD
)
398 buf
= (U_CHAR
*) mmap (0, size
, PROT_READ
, MAP_PRIVATE
, inc
->fd
, 0);
399 if (buf
== (U_CHAR
*)-1)
406 buf
= (U_CHAR
*) xmalloc (size
);
408 while (offset
< size
)
410 count
= read (inc
->fd
, buf
+ offset
, size
- offset
);
415 cpp_warning (pfile
, "%s is shorter than expected", inc
->name
);
422 else if (S_ISBLK (inc
->st
.st_mode
))
424 cpp_error (pfile
, "%s is a block device", inc
->name
);
429 /* 8 kilobytes is a sensible starting size. It ought to be
430 bigger than the kernel pipe buffer, and it's definitely
431 bigger than the majority of C source files. */
434 buf
= (U_CHAR
*) xmalloc (size
);
436 while ((count
= read (inc
->fd
, buf
+ offset
, size
- offset
)) > 0)
440 buf
= xrealloc (buf
, (size
*= 2));
446 buf
= xrealloc (buf
, offset
);
447 inc
->st
.st_size
= offset
;
454 cpp_error_from_errno (pfile
, inc
->name
);
461 struct include_file
*inc
;
467 munmap ((PTR
) inc
->buffer
, inc
->st
.st_size
);
470 free ((PTR
) inc
->buffer
);
475 /* Return 1 if the file named by FNAME has been included before in
476 any context, 0 otherwise. */
478 cpp_included (pfile
, fname
)
482 struct search_path
*path
;
486 if (IS_ABSOLUTE_PATHNAME (fname
))
488 /* Just look it up. */
489 nd
= splay_tree_lookup (pfile
->all_include_files
, (splay_tree_key
) fname
);
490 return (nd
&& nd
->value
);
493 /* Search directory path for the file. */
494 name
= (char *) alloca (strlen (fname
) + pfile
->max_include_len
+ 2);
495 for (path
= CPP_OPTION (pfile
, quote_include
); path
; path
= path
->next
)
497 memcpy (name
, path
->name
, path
->len
);
498 name
[path
->len
] = '/';
499 strcpy (&name
[path
->len
+ 1], fname
);
500 if (CPP_OPTION (pfile
, remap
))
501 n
= remap_filename (pfile
, name
, path
);
505 nd
= splay_tree_lookup (pfile
->all_include_files
, (splay_tree_key
) n
);
512 /* Search for HEADER. Return 0 if there is no such file (or it's
513 un-openable), in which case an error code will be in errno. If
514 there is no include path to use it returns NO_INCLUDE_PATH,
515 otherwise an include_file structure. If this request originates
516 from a #include_next directive, set INCLUDE_NEXT to true. */
518 static struct include_file
*
519 find_include_file (pfile
, header
, type
)
521 const cpp_token
*header
;
522 enum include_type type
;
524 const char *fname
= (const char *) header
->val
.str
.text
;
525 struct search_path
*path
;
526 struct include_file
*file
;
529 if (IS_ABSOLUTE_PATHNAME (fname
))
530 return open_file (pfile
, fname
);
532 /* For #include_next, skip in the search path past the dir in which
533 the current file was found, but if it was found via an absolute
534 path use the normal search logic. */
535 if (type
== IT_INCLUDE_NEXT
&& pfile
->buffer
->inc
->foundhere
)
536 path
= pfile
->buffer
->inc
->foundhere
->next
;
537 else if (header
->type
== CPP_HEADER_NAME
)
538 path
= CPP_OPTION (pfile
, bracket_include
);
540 path
= search_from (pfile
, type
);
544 cpp_error (pfile
, "No include path in which to find %s", fname
);
545 return NO_INCLUDE_PATH
;
548 /* Search directory path for the file. */
549 name
= (char *) alloca (strlen (fname
) + pfile
->max_include_len
+ 2);
550 for (; path
; path
= path
->next
)
552 memcpy (name
, path
->name
, path
->len
);
553 name
[path
->len
] = '/';
554 strcpy (&name
[path
->len
+ 1], fname
);
555 if (CPP_OPTION (pfile
, remap
))
556 n
= remap_filename (pfile
, name
, path
);
560 file
= open_file (pfile
, n
);
563 file
->foundhere
= path
;
571 /* Not everyone who wants to set system-header-ness on a buffer can
572 see the details of a buffer. This is an exported interface because
573 fix-header needs it. */
575 cpp_make_system_header (pfile
, syshdr
, externc
)
581 /* 1 = system header, 2 = system header to be treated as C. */
583 flags
= 1 + (externc
!= 0);
584 _cpp_do_file_change (pfile
, LC_RENAME
, pfile
->map
->to_file
,
585 SOURCE_LINE (pfile
->map
, pfile
->line
), flags
);
588 /* Report on all files that might benefit from a multiple include guard.
591 _cpp_report_missing_guards (pfile
)
595 splay_tree_foreach (pfile
->all_include_files
, report_missing_guard
,
600 report_missing_guard (n
, b
)
604 struct include_file
*f
= (struct include_file
*) n
->value
;
605 int *bannerp
= (int *)b
;
607 if (f
&& f
->cmacro
== 0 && f
->include_count
== 1)
611 fputs (_("Multiple include guards may be useful for:\n"), stderr
);
614 fputs (f
->name
, stderr
);
620 /* Create a dependency, or issue an error message as appropriate. */
622 handle_missing_header (pfile
, fname
, angle_brackets
)
627 /* We will try making the RHS pfile->buffer->sysp after 3.0. */
628 int print_dep
= CPP_PRINT_DEPS(pfile
) > (angle_brackets
629 || pfile
->system_include_depth
);
631 if (CPP_OPTION (pfile
, print_deps_missing_files
) && print_dep
)
633 if (!angle_brackets
|| IS_ABSOLUTE_PATHNAME (fname
))
634 deps_add_dep (pfile
->deps
, fname
);
637 /* If requested as a system header, assume it belongs in
638 the first system header directory. */
639 struct search_path
*ptr
= CPP_OPTION (pfile
, bracket_include
);
641 int len
= 0, fname_len
= strlen (fname
);
646 p
= (char *) alloca (len
+ fname_len
+ 2);
649 memcpy (p
, ptr
->name
, len
);
652 memcpy (p
+ len
, fname
, fname_len
+ 1);
653 deps_add_dep (pfile
->deps
, p
);
656 /* If -M was specified, then don't count this as an error, because
657 we can still produce correct output. Otherwise, we can't produce
658 correct output, because there may be dependencies we need inside
659 the missing file, and we don't know what directory this missing
660 file exists in. FIXME: Use a future cpp_diagnotic_with_errno ()
661 for both of these cases. */
662 else if (CPP_PRINT_DEPS (pfile
) && ! print_dep
)
663 cpp_warning (pfile
, "%s: %s", fname
, xstrerror (errno
));
665 cpp_error_from_errno (pfile
, fname
);
668 /* Handles #include-family directives, and the command line -imacros
669 and -include. Returns true if a buffer was stacked. */
671 _cpp_execute_include (pfile
, header
, type
)
673 const cpp_token
*header
;
674 enum include_type type
;
676 bool stacked
= false;
677 struct include_file
*inc
= find_include_file (pfile
, header
, type
);
680 handle_missing_header (pfile
, (const char *) header
->val
.str
.text
,
681 header
->type
== CPP_HEADER_NAME
);
682 else if (inc
!= NO_INCLUDE_PATH
)
684 if (header
->type
== CPP_HEADER_NAME
)
685 pfile
->system_include_depth
++;
687 stacked
= stack_include_file (pfile
, inc
);
689 if (type
== IT_IMPORT
)
690 _cpp_never_reread (inc
);
696 /* Locate HEADER, and determine whether it is newer than the current
697 file. If it cannot be located or dated, return -1, if it is newer
698 newer, return 1, otherwise 0. */
700 _cpp_compare_file_date (pfile
, header
)
702 const cpp_token
*header
;
704 struct include_file
*inc
= find_include_file (pfile
, header
, 0);
706 if (inc
== NULL
|| inc
== NO_INCLUDE_PATH
)
715 return inc
->st
.st_mtime
> pfile
->buffer
->inc
->st
.st_mtime
;
719 /* Push an input buffer and load it up with the contents of FNAME. If
720 FNAME is "", read standard input. Return true if a buffer was
723 _cpp_read_file (pfile
, fname
)
727 struct include_file
*f
= open_file (pfile
, fname
);
728 bool stacked
= false;
731 cpp_error_from_errno (pfile
, fname
);
733 stacked
= stack_include_file (pfile
, f
);
738 /* Do appropriate cleanup when a file buffer is popped off the input
741 _cpp_pop_file_buffer (pfile
, buf
)
745 struct include_file
*inc
= buf
->inc
;
747 if (pfile
->system_include_depth
)
748 pfile
->system_include_depth
--;
749 if (pfile
->include_depth
)
750 pfile
->include_depth
--;
752 /* Record the inclusion-preventing macro, which could be NULL
753 meaning no controlling macro. */
754 if (pfile
->mi_valid
&& inc
->cmacro
== NULL
)
755 inc
->cmacro
= pfile
->mi_cmacro
;
757 /* Invalidate control macros in the #including file. */
758 pfile
->mi_valid
= false;
761 if (inc
->refcnt
== 0 && DO_NOT_REREAD (inc
))
765 /* Returns the first place in the include chain to start searching for
766 "" includes. This involves stripping away the basename of the
767 current file, unless -I- was specified.
769 If we're handling -include or -imacros, use the "" chain, but with
770 the preprocessor's cwd prepended. */
771 static struct search_path
*
772 search_from (pfile
, type
)
774 enum include_type type
;
776 cpp_buffer
*buffer
= pfile
->buffer
;
779 /* Command line uses the cwd, and does not cache the result. */
780 if (type
== IT_CMDLINE
)
783 /* Ignore the current file's directory if -I- was given. */
784 if (CPP_OPTION (pfile
, ignore_srcdir
))
785 return CPP_OPTION (pfile
, quote_include
);
787 if (! buffer
->search_cached
)
789 buffer
->search_cached
= 1;
791 dlen
= lbasename (buffer
->inc
->name
) - buffer
->inc
->name
;
795 /* We don't guarantee NAME is null-terminated. This saves
796 allocating and freeing memory, and duplicating it when faking
797 buffers in cpp_push_buffer. Drop a trailing '/'. */
798 buffer
->dir
.name
= buffer
->inc
->name
;
805 buffer
->dir
.name
= ".";
809 if (dlen
> pfile
->max_include_len
)
810 pfile
->max_include_len
= dlen
;
812 buffer
->dir
.len
= dlen
;
813 buffer
->dir
.next
= CPP_OPTION (pfile
, quote_include
);
814 buffer
->dir
.sysp
= pfile
->map
->sysp
;
820 /* The file_name_map structure holds a mapping of file names for a
821 particular directory. This mapping is read from the file named
822 FILE_NAME_MAP_FILE in that directory. Such a file can be used to
823 map filenames on a file system with severe filename restrictions,
824 such as DOS. The format of the file name map file is just a series
825 of lines with two tokens on each line. The first token is the name
826 to map, and the second token is the actual name to use. */
830 struct file_name_map
*map_next
;
835 #define FILE_NAME_MAP_FILE "header.gcc"
837 /* Read a space delimited string of unlimited length from a stdio
841 read_filename_string (ch
, f
)
849 set
= alloc
= xmalloc (len
+ 1);
853 while ((ch
= getc (f
)) != EOF
&& ! is_space(ch
))
855 if (set
- alloc
== len
)
858 alloc
= xrealloc (alloc
, len
+ 1);
859 set
= alloc
+ len
/ 2;
869 /* This structure holds a linked list of file name maps, one per directory. */
871 struct file_name_map_list
873 struct file_name_map_list
*map_list_next
;
875 struct file_name_map
*map_list_map
;
878 /* Read the file name map file for DIRNAME. */
880 static struct file_name_map
*
881 read_name_map (pfile
, dirname
)
885 register struct file_name_map_list
*map_list_ptr
;
889 /* Check the cache of directories, and mappings in their remap file. */
890 for (map_list_ptr
= CPP_OPTION (pfile
, map_list
); map_list_ptr
;
891 map_list_ptr
= map_list_ptr
->map_list_next
)
892 if (! strcmp (map_list_ptr
->map_list_name
, dirname
))
893 return map_list_ptr
->map_list_map
;
895 map_list_ptr
= ((struct file_name_map_list
*)
896 xmalloc (sizeof (struct file_name_map_list
)));
897 map_list_ptr
->map_list_name
= xstrdup (dirname
);
899 /* The end of the list ends in NULL. */
900 map_list_ptr
->map_list_map
= NULL
;
902 name
= (char *) alloca (strlen (dirname
) + strlen (FILE_NAME_MAP_FILE
) + 2);
903 strcpy (name
, dirname
);
906 strcat (name
, FILE_NAME_MAP_FILE
);
907 f
= fopen (name
, "r");
909 /* Silently return NULL if we cannot open. */
913 int dirlen
= strlen (dirname
);
915 while ((ch
= getc (f
)) != EOF
)
918 struct file_name_map
*ptr
;
922 from
= read_filename_string (ch
, f
);
923 while ((ch
= getc (f
)) != EOF
&& is_hspace(ch
))
925 to
= read_filename_string (ch
, f
);
927 ptr
= ((struct file_name_map
*)
928 xmalloc (sizeof (struct file_name_map
)));
929 ptr
->map_from
= from
;
931 /* Make the real filename absolute. */
932 if (IS_ABSOLUTE_PATHNAME (to
))
936 ptr
->map_to
= xmalloc (dirlen
+ strlen (to
) + 2);
937 strcpy (ptr
->map_to
, dirname
);
938 ptr
->map_to
[dirlen
] = '/';
939 strcpy (ptr
->map_to
+ dirlen
+ 1, to
);
943 ptr
->map_next
= map_list_ptr
->map_list_map
;
944 map_list_ptr
->map_list_map
= ptr
;
946 while ((ch
= getc (f
)) != '\n')
953 /* Add this information to the cache. */
954 map_list_ptr
->map_list_next
= CPP_OPTION (pfile
, map_list
);
955 CPP_OPTION (pfile
, map_list
) = map_list_ptr
;
957 return map_list_ptr
->map_list_map
;
960 /* Remap an unsimplified path NAME based on the file_name_map (if any)
963 remap_filename (pfile
, name
, loc
)
966 struct search_path
*loc
;
968 struct file_name_map
*map
;
969 const char *from
, *p
;
974 /* Get a null-terminated path. */
975 char *dname
= alloca (loc
->len
+ 1);
976 memcpy (dname
, loc
->name
, loc
->len
);
977 dname
[loc
->len
] = '\0';
979 loc
->name_map
= read_name_map (pfile
, dname
);
984 /* This works since NAME has not been simplified yet. */
985 from
= name
+ loc
->len
+ 1;
987 for (map
= loc
->name_map
; map
; map
= map
->map_next
)
988 if (!strcmp (map
->map_from
, from
))
991 /* Try to find a mapping file for the particular directory we are
992 looking in. Thus #include <sys/types.h> will look up sys/types.h
993 in /usr/include/header.gcc and look up types.h in
994 /usr/include/sys/header.gcc. */
995 p
= strrchr (name
, '/');
999 /* We know p != name as absolute paths don't call remap_filename. */
1001 cpp_ice (pfile
, "absolute file name in remap_filename");
1003 dir
= (char *) alloca (p
- name
+ 1);
1004 memcpy (dir
, name
, p
- name
);
1005 dir
[p
- name
] = '\0';
1008 for (map
= read_name_map (pfile
, dir
); map
; map
= map
->map_next
)
1009 if (! strcmp (map
->map_from
, from
))
1015 /* Returns true if it is safe to remove the final component of path,
1016 when it is followed by a ".." component. We use lstat to avoid
1017 symlinks if we have it. If not, we can still catch errors with
1020 remove_component_p (path
)
1027 result
= lstat (path
, &s
);
1029 result
= stat (path
, &s
);
1032 /* There's no guarantee that errno will be unchanged, even on
1033 success. Cygwin's lstat(), for example, will often set errno to
1034 ENOSYS. In case of success, reset errno to zero. */
1038 return result
== 0 && S_ISDIR (s
.st_mode
);
1041 /* Simplify a path name in place, deleting redundant components. This
1042 reduces OS overhead and guarantees that equivalent paths compare
1043 the same (modulo symlinks).
1046 foo/bar/../quux foo/quux
1050 //quux //quux (POSIX allows leading // as a namespace escape)
1052 Guarantees no trailing slashes. All transforms reduce the length
1053 of the string. Returns PATH. errno is 0 if no error occurred;
1054 nonzero if an error occurred when using stat () or lstat (). */
1057 _cpp_simplify_pathname (path
)
1062 char *base
, *orig_base
;
1066 /* Don't overflow the empty path by putting a '.' in it below. */
1070 #if defined (HAVE_DOS_BASED_FILE_SYSTEM)
1071 /* Convert all backslashes to slashes. */
1072 for (from
= path
; *from
; from
++)
1073 if (*from
== '\\') *from
= '/';
1075 /* Skip over leading drive letter if present. */
1076 if (ISALPHA (path
[0]) && path
[1] == ':')
1077 from
= to
= &path
[2];
1084 /* Remove redundant leading /s. */
1093 /* 3 or more initial /s are equivalent to 1 /. */
1094 while (*++from
== '/');
1096 /* On some hosts // differs from /; Posix allows this. */
1101 base
= orig_base
= to
;
1106 while (*from
== '/')
1114 if (from
[1] == '\0')
1121 else if (from
[1] == '.' && (from
[2] == '/' || from
[2] == '\0'))
1123 /* Don't simplify if there was no previous component. */
1124 if (absolute
&& orig_base
== to
)
1129 /* Don't simplify if the previous component was "../",
1130 or if an error has already occurred with (l)stat. */
1131 if (base
!= to
&& errno
== 0)
1133 /* We don't back up if it's a symlink. */
1135 if (remove_component_p (path
))
1137 while (to
> base
&& *to
!= '/')
1147 /* Add the component separator. */
1151 /* Copy this component until the trailing null or '/'. */
1152 while (*from
!= '\0' && *from
!= '/')
1159 /* Change the empty string to "." so that it is not treated as stdin.