diff options
Diffstat (limited to 'gcc/cppfiles.c')
| -rw-r--r-- | gcc/cppfiles.c | 169 |
1 files changed, 158 insertions, 11 deletions
diff --git a/gcc/cppfiles.c b/gcc/cppfiles.c index 502e8a2..dda7ac2 100644 --- a/gcc/cppfiles.c +++ b/gcc/cppfiles.c @@ -153,6 +153,7 @@ static int report_missing_guard PARAMS ((splay_tree_node, void *)); static splay_tree_node find_or_create_entry PARAMS ((cpp_reader *, const char *)); static void handle_missing_header PARAMS ((cpp_reader *, const char *, int)); +static int remove_component_p PARAMS ((const char *)); /* Set up the splay tree we use to store information about all the file names seen in this compilation. We also have entries for each @@ -160,7 +161,7 @@ static void handle_missing_header PARAMS ((cpp_reader *, const char *, int)); don't try to open it again in future. The key of each node is the file name, after processing by - simplify_path. The path name may or may not be absolute. + cpp_simplify_path. The path name may or may not be absolute. The path string has been malloced, as is automatically freed by registering free () as the splay tree key deletion function. @@ -216,15 +217,8 @@ find_or_create_entry (pfile, fname) splay_tree_node node; struct include_file *file; char *name = xstrdup (fname); - int saved_errno = 0; - - if (pfile->cb.simplify_path) - { - errno = 0; - (pfile->cb.simplify_path) (name); - saved_errno = errno; - } + cpp_simplify_path (name); node = splay_tree_lookup (pfile->all_include_files, (splay_tree_key) name); if (node) free (name); @@ -233,7 +227,7 @@ find_or_create_entry (pfile, fname) file = xcnew (struct include_file); file->name = name; file->header_name = name; - file->err_no = saved_errno; + file->err_no = errno; node = splay_tree_insert (pfile->all_include_files, (splay_tree_key) file->name, (splay_tree_value) file); @@ -343,7 +337,7 @@ validate_pch (pfile, filename, pchname) if (INCLUDE_PCH_P (file)) { char *f = xstrdup (filename); - (pfile->cb.simplify_path) (f); + cpp_simplify_path (f); file->header_name = f; return file; } @@ -1171,3 +1165,156 @@ cpp_set_include_chains (pfile, quote, bracket, quote_ignores_source_dir) pfile->bracket_include = bracket; } } + +/* Returns true if it is safe to remove the final component of path, + when it is followed by a ".." component. We use lstat to avoid + symlinks if we have it. If not, we can still catch errors with + stat (). */ +static int +remove_component_p (path) + const char *path; +{ + struct stat s; + int result; + +#ifdef HAVE_LSTAT + result = lstat (path, &s); +#else + result = stat (path, &s); +#endif + + /* There's no guarantee that errno will be unchanged, even on + success. Cygwin's lstat(), for example, will often set errno to + ENOSYS. In case of success, reset errno to zero. */ + if (result == 0) + errno = 0; + + return result == 0 && S_ISDIR (s.st_mode); +} + +/* Simplify a path name in place, deleting redundant components. This + reduces OS overhead and guarantees that equivalent paths compare + the same (modulo symlinks). + + Transforms made: + foo/bar/../quux foo/quux + foo/./bar foo/bar + foo//bar foo/bar + /../quux /quux + //quux //quux (POSIX allows leading // as a namespace escape) + + Guarantees no trailing slashes. All transforms reduce the length + of the string. Returns PATH. errno is 0 if no error occurred; + nonzero if an error occurred when using stat () or lstat (). */ +void +cpp_simplify_path (path) + char *path ATTRIBUTE_UNUSED; +{ +#ifndef VMS + char *from, *to; + char *base, *orig_base; + int absolute = 0; + + errno = 0; + /* Don't overflow the empty path by putting a '.' in it below. */ + if (*path == '\0') + return; + +#if defined (HAVE_DOS_BASED_FILE_SYSTEM) + /* Convert all backslashes to slashes. */ + for (from = path; *from; from++) + if (*from == '\\') *from = '/'; + + /* Skip over leading drive letter if present. */ + if (ISALPHA (path[0]) && path[1] == ':') + from = to = &path[2]; + else + from = to = path; +#else + from = to = path; +#endif + + /* Remove redundant leading /s. */ + if (*from == '/') + { + absolute = 1; + to++; + from++; + if (*from == '/') + { + if (*++from == '/') + /* 3 or more initial /s are equivalent to 1 /. */ + while (*++from == '/'); + else + /* On some hosts // differs from /; Posix allows this. */ + to++; + } + } + + base = orig_base = to; + for (;;) + { + int move_base = 0; + + while (*from == '/') + from++; + + if (*from == '\0') + break; + + if (*from == '.') + { + if (from[1] == '\0') + break; + if (from[1] == '/') + { + from += 2; + continue; + } + else if (from[1] == '.' && (from[2] == '/' || from[2] == '\0')) + { + /* Don't simplify if there was no previous component. */ + if (absolute && orig_base == to) + { + from += 2; + continue; + } + /* Don't simplify if the previous component was "../", + or if an error has already occurred with (l)stat. */ + if (base != to && errno == 0) + { + /* We don't back up if it's a symlink. */ + *to = '\0'; + if (remove_component_p (path)) + { + while (to > base && *to != '/') + to--; + from += 2; + continue; + } + } + move_base = 1; + } + } + + /* Add the component separator. */ + if (to > orig_base) + *to++ = '/'; + + /* Copy this component until the trailing null or '/'. */ + while (*from != '\0' && *from != '/') + *to++ = *from++; + + if (move_base) + base = to; + } + + /* Change the empty string to "." so that it is not treated as stdin. + Null terminate. */ + if (to == path) + *to++ = '.'; + *to = '\0'; +#else /* VMS */ + errno = 0; +#endif /* !VMS */ +} |