Hide DIR definition by making it an opaque struct typedef.

Introduce dirfd() libc exported symbol replacing macro with same name,
preserve _dirfd() macro for internal use.

Replace dirp->dd_fd with dirfd() call. Avoid using dirfd as variable
name to prevent shadowing global symbol.

Sponsored by:	Google Summer Of Code 2011

13 files changed, 127 insertions, 7 deletions

diff --git a/lib/libc/gen/Makefile.inc b/lib/libc/gen/Makefile.inc
index 0362ce0..98e8183 100644
--- a/lib/libc/gen/Makefile.inc
+++ b/lib/libc/gen/Makefile.inc
@@ -9,7 +9,7 @@ SRCS+=  __getosreldate.c __xuname.c \
 	_thread_init.c \
 	alarm.c arc4random.c assert.c aux.c basename.c check_utility_compat.c \
 	clock.c closedir.c confstr.c \
-	crypt.c ctermid.c daemon.c devname.c dirname.c disklabel.c \
+	crypt.c ctermid.c daemon.c devname.c dirfd.c dirname.c disklabel.c \
 	dlfcn.c drand48.c elf_utils.c erand48.c err.c errlst.c errno.c \
 	exec.c fdevname.c feature_present.c fmtcheck.c fmtmsg.c fnmatch.c \
 	fpclassify.c frexp.c fstab.c ftok.c fts.c fts-compat.c ftw.c \
diff --git a/lib/libc/gen/Symbol.map b/lib/libc/gen/Symbol.map
index d794c0a..356bee5 100644
--- a/lib/libc/gen/Symbol.map
+++ b/lib/libc/gen/Symbol.map
@@ -382,6 +382,7 @@ FBSD_1.2 {
 };
 
 FBSD_1.3 {
+	dirfd;
 	 fdlopen;
 	__FreeBSD_libc_enter_restricted_mode;
 	getcontextx;
diff --git a/lib/libc/gen/closedir.c b/lib/libc/gen/closedir.c
index 5db351b..4b520cc 100644
--- a/lib/libc/gen/closedir.c
+++ b/lib/libc/gen/closedir.c
@@ -42,6 +42,7 @@ __FBSDID("$FreeBSD$");
 #include "un-namespace.h"
 
 #include "libc_private.h"
+#include "gen-private.h"
 #include "telldir.h"
 
 /*
diff --git a/lib/libc/gen/dirfd.c b/lib/libc/gen/dirfd.c
new file mode 100644
index 0000000..ecff700
--- /dev/null
+++ b/lib/libc/gen/dirfd.c
@@ -0,0 +1,48 @@
+/*-
+ * Copyright (c) 1989, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include "namespace.h"
+#include <sys/param.h>
+
+#include <dirent.h>
+#include "un-namespace.h"
+
+#include "gen-private.h"
+
+int
+dirfd(DIR *dirp)
+{
+
+	return (_dirfd(dirp));
+}
diff --git a/lib/libc/gen/fts-compat.c b/lib/libc/gen/fts-compat.c
index a6ddde4..6585416 100644
--- a/lib/libc/gen/fts-compat.c
+++ b/lib/libc/gen/fts-compat.c
@@ -52,6 +52,8 @@ __FBSDID("$FreeBSD$");
 #include "fts-compat.h"
 #include "un-namespace.h"
 
+#include "gen-private.h"
+
 FTSENT	*__fts_children_44bsd(FTS *, int);
 int	 __fts_close_44bsd(FTS *);
 void	*__fts_get_clientptr_44bsd(FTS *);
@@ -711,7 +713,7 @@ fts_build(sp, type)
 	 */
 	cderrno = 0;
 	if (nlinks || type == BREAD) {
-		if (fts_safe_changedir(sp, cur, dirfd(dirp), NULL)) {
+		if (fts_safe_changedir(sp, cur, _dirfd(dirp), NULL)) {
 			if (nlinks && type == BREAD)
 				cur->fts_errno = errno;
 			cur->fts_flags |= FTS_DONTCHDIR;
diff --git a/lib/libc/gen/fts.c b/lib/libc/gen/fts.c
index 1344464..153b8da 100644
--- a/lib/libc/gen/fts.c
+++ b/lib/libc/gen/fts.c
@@ -52,6 +52,8 @@ __FBSDID("$FreeBSD$");
 #include <unistd.h>
 #include "un-namespace.h"
 
+#include "gen-private.h"
+
 static FTSENT	*fts_alloc(FTS *, char *, size_t);
 static FTSENT	*fts_build(FTS *, int);
 static void	 fts_lfree(FTSENT *);
@@ -697,7 +699,7 @@ fts_build(FTS *sp, int type)
 	 */
 	cderrno = 0;
 	if (nlinks || type == BREAD) {
-		if (fts_safe_changedir(sp, cur, dirfd(dirp), NULL)) {
+		if (fts_safe_changedir(sp, cur, _dirfd(dirp), NULL)) {
 			if (nlinks && type == BREAD)
 				cur->fts_errno = errno;
 			cur->fts_flags |= FTS_DONTCHDIR;
diff --git a/lib/libc/gen/gen-private.h b/lib/libc/gen/gen-private.h
new file mode 100644
index 0000000..e8854ad
--- /dev/null
+++ b/lib/libc/gen/gen-private.h
@@ -0,0 +1,59 @@
+/*-
+ * Copyright (c) 1989, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _GEN_PRIVATE_H_
+#define	_GEN_PRIVATE_H_
+
+struct _telldir;		/* see telldir.h */
+struct pthread_mutex;
+
+/*
+ * Structure describing an open directory.
+ *
+ * NOTE. Change structure layout with care, at least dd_fd field has to
+ * remain unchanged to guarantee backward compatibility.
+ */
+struct _dirdesc {
+	int	dd_fd;		/* file descriptor associated with directory */
+	long	dd_loc;		/* offset in current buffer */
+	long	dd_size;	/* amount of data returned by getdirentries */
+	char	*dd_buf;	/* data buffer */
+	int	dd_len;		/* size of data buffer */
+	long	dd_seek;	/* magic cookie returned by getdirentries */
+	long	dd_rewind;	/* magic cookie for rewinding */
+	int	dd_flags;	/* flags for readdir */
+	struct pthread_mutex	*dd_lock;	/* lock */
+	struct _telldir *dd_td;	/* telldir position recording */
+};
+
+#define	_dirfd(dirp)	((dirp)->dd_fd)
+
+#endif /* !_GEN_PRIVATE_H_ */
diff --git a/lib/libc/gen/getcwd.c b/lib/libc/gen/getcwd.c
index c886dde..40feedf 100644
--- a/lib/libc/gen/getcwd.c
+++ b/lib/libc/gen/getcwd.c
@@ -46,6 +46,8 @@ __FBSDID("$FreeBSD$");
 #include <unistd.h>
 #include "un-namespace.h"
 
+#include "gen-private.h"
+
 #define	ISDOT(dp) \
 	(dp->d_name[0] == '.' && (dp->d_name[1] == '\0' || \
 	    (dp->d_name[1] == '.' && dp->d_name[2] == '\0')))
@@ -117,7 +119,7 @@ getcwd(pt, size)
 
 	for (first = 1;; first = 0) {
 		/* Stat the current level. */
-		if (dir != NULL ? _fstat(dirfd(dir), &s) : lstat(".", &s))
+		if (dir != NULL ? _fstat(_dirfd(dir), &s) : lstat(".", &s))
 			goto err;
 
 		/* Save current node values. */
@@ -139,13 +141,13 @@ getcwd(pt, size)
 		}
 
 		/* Open and stat parent directory. */
-		fd = _openat(dir != NULL ? dirfd(dir) : AT_FDCWD,
+		fd = _openat(dir != NULL ? _dirfd(dir) : AT_FDCWD,
 				"..", O_RDONLY);
 		if (fd == -1)
 			goto err;
 		if (dir)
 			(void) closedir(dir);
-		if (!(dir = fdopendir(fd)) || _fstat(dirfd(dir), &s)) {
+		if (!(dir = fdopendir(fd)) || _fstat(_dirfd(dir), &s)) {
 			_close(fd);
 			goto err;
 		}
@@ -171,7 +173,7 @@ getcwd(pt, size)
 					continue;
 
 				/* Save the first error for later. */
-				if (fstatat(dirfd(dir), dp->d_name, &s,
+				if (fstatat(_dirfd(dir), dp->d_name, &s,
 				    AT_SYMLINK_NOFOLLOW)) {
 					if (!save_errno)
 						save_errno = errno;
diff --git a/lib/libc/gen/opendir.c b/lib/libc/gen/opendir.c
index 3beead7..4366399 100644
--- a/lib/libc/gen/opendir.c
+++ b/lib/libc/gen/opendir.c
@@ -46,6 +46,7 @@ __FBSDID("$FreeBSD$");
 #include <unistd.h>
 #include "un-namespace.h"
 
+#include "gen-private.h"
 #include "telldir.h"
 
 static DIR * __opendir_common(int, const char *, int);
diff --git a/lib/libc/gen/readdir.c b/lib/libc/gen/readdir.c
index b4b4c39..324870b 100644
--- a/lib/libc/gen/readdir.c
+++ b/lib/libc/gen/readdir.c
@@ -42,6 +42,7 @@ __FBSDID("$FreeBSD$");
 #include "un-namespace.h"
 
 #include "libc_private.h"
+#include "gen-private.h"
 #include "telldir.h"
 
 /*
diff --git a/lib/libc/gen/rewinddir.c b/lib/libc/gen/rewinddir.c
index 45e450d..0eb091a 100644
--- a/lib/libc/gen/rewinddir.c
+++ b/lib/libc/gen/rewinddir.c
@@ -36,6 +36,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/types.h>
 #include <dirent.h>
 
+#include "gen-private.h"
 #include "telldir.h"
 
 void
diff --git a/lib/libc/gen/seekdir.c b/lib/libc/gen/seekdir.c
index 45ed6b5..e9851a7 100644
--- a/lib/libc/gen/seekdir.c
+++ b/lib/libc/gen/seekdir.c
@@ -40,6 +40,7 @@ __FBSDID("$FreeBSD$");
 #include "un-namespace.h"
 
 #include "libc_private.h"
+#include "gen-private.h"
 #include "telldir.h"
 
 /*
diff --git a/lib/libc/gen/telldir.c b/lib/libc/gen/telldir.c
index c217333..4954b97 100644
--- a/lib/libc/gen/telldir.c
+++ b/lib/libc/gen/telldir.c
@@ -43,6 +43,7 @@ __FBSDID("$FreeBSD$");
 #include "un-namespace.h"
 
 #include "libc_private.h"
+#include "gen-private.h"
 #include "telldir.h"
 
 /*