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 /* Variable length record files on VMS will have a stat size that includes
77 record control characters that won't be included in the read size. */
79 # define FAB_C_VAR 2 /* variable length records (see Starlet fabdef.h) */
80 # define STAT_SIZE_TOO_BIG(ST) ((ST).st_fab_rfm == FAB_C_VAR)
82 # define STAT_SIZE_TOO_BIG(ST) 0
85 /* The cmacro works like this: If it's NULL, the file is to be
86 included again. If it's NEVER_REREAD, the file is never to be
87 included again. Otherwise it is a macro hashnode, and the file is
88 to be included again if the macro is defined. */
89 #define NEVER_REREAD ((const cpp_hashnode *)-1)
90 #define DO_NOT_REREAD(inc) \
91 ((inc)->cmacro && ((inc)->cmacro == NEVER_REREAD \
92 || (inc)->cmacro->type == NT_MACRO))
93 #define NO_INCLUDE_PATH ((struct include_file *) -1)
95 static struct file_name_map
*read_name_map
96 PARAMS ((cpp_reader
*, const char *));
97 static char *read_filename_string
PARAMS ((int, FILE *));
98 static char *remap_filename
PARAMS ((cpp_reader
*, char *,
99 struct search_path
*));
100 static struct search_path
*search_from
PARAMS ((cpp_reader
*,
102 static struct include_file
*
103 find_include_file
PARAMS ((cpp_reader
*, const cpp_token
*,
105 static struct include_file
*open_file
PARAMS ((cpp_reader
*, const char *));
106 static int read_include_file
PARAMS ((cpp_reader
*, struct include_file
*));
107 static bool stack_include_file
PARAMS ((cpp_reader
*, struct include_file
*));
108 static void purge_cache
PARAMS ((struct include_file
*));
109 static void destroy_node
PARAMS ((splay_tree_value
));
110 static int report_missing_guard
PARAMS ((splay_tree_node
, void *));
111 static splay_tree_node find_or_create_entry
PARAMS ((cpp_reader
*,
113 static void handle_missing_header
PARAMS ((cpp_reader
*, const char *, int));
114 static int remove_component_p
PARAMS ((const char *));
116 /* Set up the splay tree we use to store information about all the
117 file names seen in this compilation. We also have entries for each
118 file we tried to open but failed; this saves system calls since we
119 don't try to open it again in future.
121 The key of each node is the file name, after processing by
122 _cpp_simplify_pathname. The path name may or may not be absolute.
123 The path string has been malloced, as is automatically freed by
124 registering free () as the splay tree key deletion function.
126 A node's value is a pointer to a struct include_file, and is never
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
,
138 /* Tear down the splay tree. */
140 _cpp_cleanup_includes (pfile
)
143 splay_tree_delete (pfile
->all_include_files
);
146 /* Free a node. The path string is automatically freed. */
151 struct include_file
*f
= (struct include_file
*)v
;
160 /* Mark a file to not be reread (e.g. #import, read failure). */
162 _cpp_never_reread (file
)
163 struct include_file
*file
;
165 file
->cmacro
= NEVER_REREAD
;
168 /* Lookup a filename, which is simplified after making a copy, and
169 create an entry if none exists. errno is nonzero iff a (reported)
170 stat() error occurred during simplification. */
171 static splay_tree_node
172 find_or_create_entry (pfile
, fname
)
176 splay_tree_node node
;
177 struct include_file
*file
;
178 char *name
= xstrdup (fname
);
180 _cpp_simplify_pathname (name
);
181 node
= splay_tree_lookup (pfile
->all_include_files
, (splay_tree_key
) name
);
186 file
= xcnew (struct include_file
);
188 file
->err_no
= errno
;
189 node
= splay_tree_insert (pfile
->all_include_files
,
190 (splay_tree_key
) file
->name
,
191 (splay_tree_value
) file
);
197 /* Enter a file name in the splay tree, for the sake of cpp_included. */
199 _cpp_fake_include (pfile
, fname
)
203 find_or_create_entry (pfile
, fname
);
206 /* Given a file name, look it up in the cache; if there is no entry,
207 create one with a non-NULL value (regardless of success in opening
208 the file). If the file doesn't exist or is inaccessible, this
209 entry is flagged so we don't attempt to open it again in the
210 future. If the file isn't open, open it. The empty string is
211 interpreted as stdin.
213 Returns an include_file structure with an open file descriptor on
214 success, or NULL on failure. */
216 static struct include_file
*
217 open_file (pfile
, filename
)
219 const char *filename
;
221 splay_tree_node nd
= find_or_create_entry (pfile
, filename
);
222 struct include_file
*file
= (struct include_file
*) nd
->value
;
226 /* Ugh. handle_missing_header () needs errno to be set. */
227 errno
= file
->err_no
;
231 /* Don't reopen an idempotent file. */
232 if (DO_NOT_REREAD (file
))
235 /* Don't reopen one which is already loaded. */
236 if (file
->buffer
!= NULL
)
239 /* We used to open files in nonblocking mode, but that caused more
240 problems than it solved. Do take care not to acquire a
241 controlling terminal by mistake (this can't happen on sane
242 systems, but paranoia is a virtue).
244 Use the three-argument form of open even though we aren't
245 specifying O_CREAT, to defend against broken system headers.
247 O_BINARY tells some runtime libraries (notably DJGPP) not to do
248 newline translation; we can handle DOS line breaks just fine
251 Special case: the empty string is translated to stdin. */
253 if (filename
[0] == '\0')
256 file
->fd
= open (file
->name
, O_RDONLY
| O_NOCTTY
| O_BINARY
, 0666);
258 if (file
->fd
!= -1 && fstat (file
->fd
, &file
->st
) == 0)
260 if (!S_ISDIR (file
->st
.st_mode
))
263 /* If it's a directory, we return null and continue the search
264 as the file we're looking for may appear elsewhere in the
271 file
->err_no
= errno
;
275 /* Place the file referenced by INC into a new buffer on the buffer
276 stack, unless there are errors, or the file is not re-included
277 because of e.g. multiple-include guards. Returns true if a buffer
281 stack_include_file (pfile
, inc
)
283 struct include_file
*inc
;
287 const char *filename
;
289 if (DO_NOT_REREAD (inc
))
292 sysp
= MAX ((pfile
->map
? pfile
->map
->sysp
: 0),
293 (inc
->foundhere
? inc
->foundhere
->sysp
: 0));
295 /* For -M, add the file to the dependencies on its first inclusion. */
296 if (CPP_OPTION (pfile
, print_deps
) > sysp
&& !inc
->include_count
)
297 deps_add_dep (pfile
->deps
, inc
->name
);
302 if (read_include_file (pfile
, inc
))
304 /* If an error occurs, do not try to read this file again. */
305 _cpp_never_reread (inc
);
308 /* Mark a regular, zero-length file never-reread. We read it,
309 NUL-terminate it, and stack it once, so preprocessing a main
310 file of zero length does not raise an error. */
311 if (S_ISREG (inc
->st
.st_mode
) && inc
->st
.st_size
== 0)
312 _cpp_never_reread (inc
);
318 /* We don't want MI guard advice for the main file. */
319 inc
->include_count
++;
322 fp
= cpp_push_buffer (pfile
, inc
->buffer
, inc
->st
.st_size
,
323 /* from_stage3 */ CPP_OPTION (pfile
, preprocessed
), 0);
327 /* Initialise controlling macro state. */
328 pfile
->mi_valid
= true;
329 pfile
->mi_cmacro
= 0;
331 /* Generate the call back. */
332 filename
= inc
->name
;
333 if (*filename
== '\0')
334 filename
= "<stdin>";
335 _cpp_do_file_change (pfile
, LC_ENTER
, filename
, 1, sysp
);
340 /* Read the file referenced by INC into the file cache.
342 If fd points to a plain file, we might be able to mmap it; we can
343 definitely allocate the buffer all at once. If fd is a pipe or
344 terminal, we can't do either. If fd is something weird, like a
345 block device, we don't want to read it at all.
347 Unfortunately, different systems use different st.st_mode values
348 for pipes: some have S_ISFIFO, some S_ISSOCK, some are buggy and
349 zero the entire struct stat except a couple fields. Hence we don't
350 even try to figure out what something is, except for plain files
353 FIXME: Flush file cache and try again if we run out of memory. */
356 read_include_file (pfile
, inc
)
358 struct include_file
*inc
;
360 ssize_t size
, offset
, count
;
363 static int pagesize
= -1;
366 if (S_ISREG (inc
->st
.st_mode
))
368 /* off_t might have a wider range than ssize_t - in other words,
369 the max size of a file might be bigger than the address
370 space. We can't handle a file that large. (Anyone with
371 a single source file bigger than 2GB needs to rethink
372 their coding style.) Some systems (e.g. AIX 4.1) define
373 SSIZE_MAX to be much smaller than the actual range of the
374 type. Use INTTYPE_MAXIMUM unconditionally to ensure this
376 if (inc
->st
.st_size
> INTTYPE_MAXIMUM (ssize_t
))
378 cpp_error (pfile
, "%s is too large", inc
->name
);
381 size
= inc
->st
.st_size
;
386 pagesize
= getpagesize ();
388 /* Use mmap if the file is big enough to be worth it (controlled
389 by MMAP_THRESHOLD) and if we can safely count on there being
390 at least one readable NUL byte after the end of the file's
391 contents. This is true for all tested operating systems when
392 the file size is not an exact multiple of the page size. */
393 if (size
/ pagesize
>= MMAP_THRESHOLD
394 && (size
% pagesize
) != 0)
396 buf
= (U_CHAR
*) mmap (0, size
, PROT_READ
, MAP_PRIVATE
, inc
->fd
, 0);
397 if (buf
== (U_CHAR
*)-1)
404 buf
= (U_CHAR
*) xmalloc (size
+ 1);
406 while (offset
< size
)
408 count
= read (inc
->fd
, buf
+ offset
, size
- offset
);
413 if (!STAT_SIZE_TOO_BIG (inc
->st
))
415 (pfile
, "%s is shorter than expected", inc
->name
);
417 buf
= xrealloc (buf
, size
+ 1);
418 inc
->st
.st_size
= size
;
423 /* The lexer requires that the buffer be NUL-terminated. */
427 else if (S_ISBLK (inc
->st
.st_mode
))
429 cpp_error (pfile
, "%s is a block device", inc
->name
);
434 /* 8 kilobytes is a sensible starting size. It ought to be
435 bigger than the kernel pipe buffer, and it's definitely
436 bigger than the majority of C source files. */
439 buf
= (U_CHAR
*) xmalloc (size
+ 1);
441 while ((count
= read (inc
->fd
, buf
+ offset
, size
- offset
)) > 0)
447 buf
= xrealloc (buf
, size
+ 1);
453 if (offset
+ 1 < size
)
454 buf
= xrealloc (buf
, offset
+ 1);
456 /* The lexer requires that the buffer be NUL-terminated. */
458 inc
->st
.st_size
= offset
;
465 cpp_error_from_errno (pfile
, inc
->name
);
472 struct include_file
*inc
;
478 munmap ((PTR
) inc
->buffer
, inc
->st
.st_size
);
481 free ((PTR
) inc
->buffer
);
486 /* Return 1 if the file named by FNAME has been included before in
487 any context, 0 otherwise. */
489 cpp_included (pfile
, fname
)
493 struct search_path
*path
;
497 if (IS_ABSOLUTE_PATHNAME (fname
))
499 /* Just look it up. */
500 nd
= splay_tree_lookup (pfile
->all_include_files
, (splay_tree_key
) fname
);
501 return (nd
&& nd
->value
);
504 /* Search directory path for the file. */
505 name
= (char *) alloca (strlen (fname
) + pfile
->max_include_len
+ 2);
506 for (path
= CPP_OPTION (pfile
, quote_include
); path
; path
= path
->next
)
508 memcpy (name
, path
->name
, path
->len
);
509 name
[path
->len
] = '/';
510 strcpy (&name
[path
->len
+ 1], fname
);
511 if (CPP_OPTION (pfile
, remap
))
512 n
= remap_filename (pfile
, name
, path
);
516 nd
= splay_tree_lookup (pfile
->all_include_files
, (splay_tree_key
) n
);
523 /* Search for HEADER. Return 0 if there is no such file (or it's
524 un-openable), in which case an error code will be in errno. If
525 there is no include path to use it returns NO_INCLUDE_PATH,
526 otherwise an include_file structure. If this request originates
527 from a #include_next directive, set INCLUDE_NEXT to true. */
529 static struct include_file
*
530 find_include_file (pfile
, header
, type
)
532 const cpp_token
*header
;
533 enum include_type type
;
535 const char *fname
= (const char *) header
->val
.str
.text
;
536 struct search_path
*path
;
537 struct include_file
*file
;
540 if (IS_ABSOLUTE_PATHNAME (fname
))
541 return open_file (pfile
, fname
);
543 /* For #include_next, skip in the search path past the dir in which
544 the current file was found, but if it was found via an absolute
545 path use the normal search logic. */
546 if (type
== IT_INCLUDE_NEXT
&& pfile
->buffer
->inc
->foundhere
)
547 path
= pfile
->buffer
->inc
->foundhere
->next
;
548 else if (header
->type
== CPP_HEADER_NAME
)
549 path
= CPP_OPTION (pfile
, bracket_include
);
551 path
= search_from (pfile
, type
);
555 cpp_error (pfile
, "no include path in which to find %s", fname
);
556 return NO_INCLUDE_PATH
;
559 /* Search directory path for the file. */
560 name
= (char *) alloca (strlen (fname
) + pfile
->max_include_len
+ 2);
561 for (; path
; path
= path
->next
)
564 memcpy (name
, path
->name
, len
);
565 /* Don't turn / into // or // into ///; // may be a namespace
567 if (name
[len
-1] == '/')
570 strcpy (&name
[len
+ 1], fname
);
571 if (CPP_OPTION (pfile
, remap
))
572 n
= remap_filename (pfile
, name
, path
);
576 file
= open_file (pfile
, n
);
579 file
->foundhere
= path
;
587 /* Not everyone who wants to set system-header-ness on a buffer can
588 see the details of a buffer. This is an exported interface because
589 fix-header needs it. */
591 cpp_make_system_header (pfile
, syshdr
, externc
)
597 /* 1 = system header, 2 = system header to be treated as C. */
599 flags
= 1 + (externc
!= 0);
600 _cpp_do_file_change (pfile
, LC_RENAME
, pfile
->map
->to_file
,
601 SOURCE_LINE (pfile
->map
, pfile
->line
), flags
);
604 /* Report on all files that might benefit from a multiple include guard.
607 _cpp_report_missing_guards (pfile
)
611 splay_tree_foreach (pfile
->all_include_files
, report_missing_guard
,
616 report_missing_guard (n
, b
)
620 struct include_file
*f
= (struct include_file
*) n
->value
;
621 int *bannerp
= (int *)b
;
623 if (f
&& f
->cmacro
== 0 && f
->include_count
== 1)
627 fputs (_("Multiple include guards may be useful for:\n"), stderr
);
630 fputs (f
->name
, stderr
);
636 /* Create a dependency, or issue an error message as appropriate. */
638 handle_missing_header (pfile
, fname
, angle_brackets
)
643 int print_dep
= CPP_PRINT_DEPS(pfile
) > (angle_brackets
|| pfile
->map
->sysp
);
645 if (CPP_OPTION (pfile
, print_deps_missing_files
) && print_dep
)
647 if (!angle_brackets
|| IS_ABSOLUTE_PATHNAME (fname
))
648 deps_add_dep (pfile
->deps
, fname
);
651 /* If requested as a system header, assume it belongs in
652 the first system header directory. */
653 struct search_path
*ptr
= CPP_OPTION (pfile
, bracket_include
);
655 int len
= 0, fname_len
= strlen (fname
);
660 p
= (char *) alloca (len
+ fname_len
+ 2);
663 memcpy (p
, ptr
->name
, len
);
666 memcpy (p
+ len
, fname
, fname_len
+ 1);
667 deps_add_dep (pfile
->deps
, p
);
670 /* If -M was specified, then don't count this as an error, because
671 we can still produce correct output. Otherwise, we can't produce
672 correct output, because there may be dependencies we need inside
673 the missing file, and we don't know what directory this missing
674 file exists in. FIXME: Use a future cpp_diagnostic_with_errno ()
675 for both of these cases. */
676 else if (CPP_PRINT_DEPS (pfile
) && ! print_dep
)
677 cpp_warning (pfile
, "%s: %s", fname
, xstrerror (errno
));
679 cpp_error_from_errno (pfile
, fname
);
682 /* Handles #include-family directives, and the command line -imacros
683 and -include. Returns true if a buffer was stacked. */
685 _cpp_execute_include (pfile
, header
, type
)
687 const cpp_token
*header
;
688 enum include_type type
;
690 bool stacked
= false;
691 struct include_file
*inc
= find_include_file (pfile
, header
, type
);
694 handle_missing_header (pfile
, (const char *) header
->val
.str
.text
,
695 header
->type
== CPP_HEADER_NAME
);
696 else if (inc
!= NO_INCLUDE_PATH
)
698 stacked
= stack_include_file (pfile
, inc
);
700 if (type
== IT_IMPORT
)
701 _cpp_never_reread (inc
);
707 /* Locate HEADER, and determine whether it is newer than the current
708 file. If it cannot be located or dated, return -1, if it is newer
709 newer, return 1, otherwise 0. */
711 _cpp_compare_file_date (pfile
, header
)
713 const cpp_token
*header
;
715 struct include_file
*inc
= find_include_file (pfile
, header
, 0);
717 if (inc
== NULL
|| inc
== NO_INCLUDE_PATH
)
726 return inc
->st
.st_mtime
> pfile
->buffer
->inc
->st
.st_mtime
;
730 /* Push an input buffer and load it up with the contents of FNAME. If
731 FNAME is "", read standard input. Return true if a buffer was
734 _cpp_read_file (pfile
, fname
)
738 struct include_file
*f
= open_file (pfile
, fname
);
742 cpp_error_from_errno (pfile
, fname
);
746 return stack_include_file (pfile
, f
);
749 /* Do appropriate cleanup when a file buffer is popped off the input
750 stack. Push the next -include file, if any remain. */
752 _cpp_pop_file_buffer (pfile
, inc
)
754 struct include_file
*inc
;
756 /* Record the inclusion-preventing macro, which could be NULL
757 meaning no controlling macro. */
758 if (pfile
->mi_valid
&& inc
->cmacro
== NULL
)
759 inc
->cmacro
= pfile
->mi_cmacro
;
761 /* Invalidate control macros in the #including file. */
762 pfile
->mi_valid
= false;
765 if (inc
->refcnt
== 0 && DO_NOT_REREAD (inc
))
768 /* Don't generate a callback for popping the main file. */
771 _cpp_do_file_change (pfile
, LC_LEAVE
, 0, 0, 0);
773 /* Finally, push the next -included file, if any. */
774 if (!pfile
->buffer
->prev
)
775 _cpp_push_next_buffer (pfile
);
779 /* Returns the first place in the include chain to start searching for
780 "" includes. This involves stripping away the basename of the
781 current file, unless -I- was specified.
783 If we're handling -include or -imacros, use the "" chain, but with
784 the preprocessor's cwd prepended. */
785 static struct search_path
*
786 search_from (pfile
, type
)
788 enum include_type type
;
790 cpp_buffer
*buffer
= pfile
->buffer
;
793 /* Command line uses the cwd, and does not cache the result. */
794 if (type
== IT_CMDLINE
)
797 /* Ignore the current file's directory if -I- was given. */
798 if (CPP_OPTION (pfile
, ignore_srcdir
))
799 return CPP_OPTION (pfile
, quote_include
);
801 if (! buffer
->search_cached
)
803 buffer
->search_cached
= 1;
805 dlen
= lbasename (buffer
->inc
->name
) - buffer
->inc
->name
;
809 /* We don't guarantee NAME is null-terminated. This saves
810 allocating and freeing memory. Drop a trailing '/'. */
811 buffer
->dir
.name
= buffer
->inc
->name
;
818 buffer
->dir
.name
= ".";
822 if (dlen
> pfile
->max_include_len
)
823 pfile
->max_include_len
= dlen
;
825 buffer
->dir
.len
= dlen
;
826 buffer
->dir
.next
= CPP_OPTION (pfile
, quote_include
);
827 buffer
->dir
.sysp
= pfile
->map
->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 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 an unsimplified path NAME based on the file_name_map (if any)
976 remap_filename (pfile
, name
, loc
)
979 struct search_path
*loc
;
981 struct file_name_map
*map
;
982 const char *from
, *p
;
987 /* Get a null-terminated path. */
988 char *dname
= alloca (loc
->len
+ 1);
989 memcpy (dname
, loc
->name
, loc
->len
);
990 dname
[loc
->len
] = '\0';
992 loc
->name_map
= read_name_map (pfile
, dname
);
997 /* This works since NAME has not been simplified yet. */
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 /* Returns true if it is safe to remove the final component of path,
1029 when it is followed by a ".." component. We use lstat to avoid
1030 symlinks if we have it. If not, we can still catch errors with
1033 remove_component_p (path
)
1040 result
= lstat (path
, &s
);
1042 result
= stat (path
, &s
);
1045 /* There's no guarantee that errno will be unchanged, even on
1046 success. Cygwin's lstat(), for example, will often set errno to
1047 ENOSYS. In case of success, reset errno to zero. */
1051 return result
== 0 && S_ISDIR (s
.st_mode
);
1054 /* Simplify a path name in place, deleting redundant components. This
1055 reduces OS overhead and guarantees that equivalent paths compare
1056 the same (modulo symlinks).
1059 foo/bar/../quux foo/quux
1063 //quux //quux (POSIX allows leading // as a namespace escape)
1065 Guarantees no trailing slashes. All transforms reduce the length
1066 of the string. Returns PATH. errno is 0 if no error occurred;
1067 nonzero if an error occurred when using stat () or lstat (). */
1070 _cpp_simplify_pathname (path
)
1075 char *base
, *orig_base
;
1079 /* Don't overflow the empty path by putting a '.' in it below. */
1083 #if defined (HAVE_DOS_BASED_FILE_SYSTEM)
1084 /* Convert all backslashes to slashes. */
1085 for (from
= path
; *from
; from
++)
1086 if (*from
== '\\') *from
= '/';
1088 /* Skip over leading drive letter if present. */
1089 if (ISALPHA (path
[0]) && path
[1] == ':')
1090 from
= to
= &path
[2];
1097 /* Remove redundant leading /s. */
1106 /* 3 or more initial /s are equivalent to 1 /. */
1107 while (*++from
== '/');
1109 /* On some hosts // differs from /; Posix allows this. */
1114 base
= orig_base
= to
;
1119 while (*from
== '/')
1127 if (from
[1] == '\0')
1134 else if (from
[1] == '.' && (from
[2] == '/' || from
[2] == '\0'))
1136 /* Don't simplify if there was no previous component. */
1137 if (absolute
&& orig_base
== to
)
1142 /* Don't simplify if the previous component was "../",
1143 or if an error has already occurred with (l)stat. */
1144 if (base
!= to
&& errno
== 0)
1146 /* We don't back up if it's a symlink. */
1148 if (remove_component_p (path
))
1150 while (to
> base
&& *to
!= '/')
1160 /* Add the component separator. */
1164 /* Copy this component until the trailing null or '/'. */
1165 while (*from
!= '\0' && *from
!= '/')
1172 /* Change the empty string to "." so that it is not treated as stdin.