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

17 files changed, 139 insertions, 34 deletions

diff --git a/include/dirent.h b/include/dirent.h
index e3ef149..941a977 100644
--- a/include/dirent.h
+++ b/include/dirent.h
@@ -55,24 +55,8 @@
 /* definitions for library routines operating on directories. */
 #define	DIRBLKSIZ	1024
 
-struct _telldir;		/* see telldir.h */
-struct pthread_mutex;
-
-/* structure describing an open directory. */
-typedef 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 */
-} DIR;
-
-#define	dirfd(dirp)	((dirp)->dd_fd)
+struct _dirdesc;
+typedef struct _dirdesc DIR;
 
 /* flags for opendir2 */
 #define DTF_HIDEW	0x0001	/* hide whiteout entries */
@@ -91,6 +75,7 @@ typedef	void *	DIR;
 __BEGIN_DECLS
 #if __POSIX_VISIBLE >= 200809 || __XSI_VISIBLE >= 700
 int	 alphasort(const struct dirent **, const struct dirent **);
+int	 dirfd(DIR *);
 #endif
 #if __BSD_VISIBLE
 DIR	*__opendir2(const char *, int);
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"
 
 /*
diff --git a/usr.sbin/cpucontrol/cpucontrol.c b/usr.sbin/cpucontrol/cpucontrol.c
index 7477007..8738612 100644
--- a/usr.sbin/cpucontrol/cpucontrol.c
+++ b/usr.sbin/cpucontrol/cpucontrol.c
@@ -292,7 +292,7 @@ do_update(const char *dev)
 	int error;
 	struct ucode_handler *handler;
 	struct datadir *dir;
-	DIR *dirfd;
+	DIR *dirp;
 	struct dirent *direntry;
 	char buf[MAXPATHLEN];
 
@@ -321,12 +321,12 @@ do_update(const char *dev)
 	 * Process every image in specified data directories.
 	 */
 	SLIST_FOREACH(dir, &datadirs, next) {
-		dirfd  = opendir(dir->path);
-		if (dirfd == NULL) {
+		dirp = opendir(dir->path);
+		if (dirp == NULL) {
 			WARNX(1, "skipping directory %s: not accessible", dir->path);
 			continue;
 		}
-		while ((direntry = readdir(dirfd)) != NULL) {
+		while ((direntry = readdir(dirp)) != NULL) {
 			if (direntry->d_namlen == 0)
 				continue;
 			error = snprintf(buf, sizeof(buf), "%s/%s", dir->path,
@@ -340,7 +340,7 @@ do_update(const char *dev)
 			}
 			handler->update(dev, buf);
 		}
-		error = closedir(dirfd);
+		error = closedir(dirp);
 		if (error != 0)
 			WARN(0, "closedir(%s)", dir->path);
 	}
diff --git a/usr.sbin/lpr/common_source/common.c b/usr.sbin/lpr/common_source/common.c
index d28ac1f..819d7dd 100644
--- a/usr.sbin/lpr/common_source/common.c
+++ b/usr.sbin/lpr/common_source/common.c
@@ -130,7 +130,7 @@ getq(const struct printer *pp, struct jobqueue *(*namelist[]))
 		seteuid(uid);
 		return (-1);
 	}
-	if (fstat(dirp->dd_fd, &stbuf) < 0)
+	if (fstat(dirfd(dirp), &stbuf) < 0)
 		goto errdone;
 	seteuid(uid);
 
diff --git a/usr.sbin/newsyslog/newsyslog.c b/usr.sbin/newsyslog/newsyslog.c
index 7ebdddc..227ea00 100644
--- a/usr.sbin/newsyslog/newsyslog.c
+++ b/usr.sbin/newsyslog/newsyslog.c
@@ -1451,7 +1451,7 @@ static void
 delete_oldest_timelog(const struct conf_entry *ent, const char *archive_dir)
 {
 	char *logfname, *s, *dir, errbuf[80];
-	int dirfd, i, logcnt, max_logcnt, valid;
+	int dir_fd, i, logcnt, max_logcnt, valid;
 	struct oldlog_entry *oldlogs;
 	size_t logfname_len;
 	struct dirent *dp;
@@ -1486,7 +1486,7 @@ delete_oldest_timelog(const struct conf_entry *ent, const char *archive_dir)
 	/* First we create a 'list' of all archived logfiles */
 	if ((dirp = opendir(dir)) == NULL)
 		err(1, "Cannot open log directory '%s'", dir);
-	dirfd = dirfd(dirp);
+	dir_fd = dirfd(dirp);
 	while ((dp = readdir(dirp)) != NULL) {
 		if (dp->d_type != DT_REG)
 			continue;
@@ -1578,7 +1578,7 @@ delete_oldest_timelog(const struct conf_entry *ent, const char *archive_dir)
 			if (noaction)
 				printf("\trm -f %s/%s\n", dir,
 				    oldlogs[i].fname);
-			else if (unlinkat(dirfd, oldlogs[i].fname, 0) != 0) {
+			else if (unlinkat(dir_fd, oldlogs[i].fname, 0) != 0) {
 				snprintf(errbuf, sizeof(errbuf),
 				    "Could not delet old logfile '%s'",
 				    oldlogs[i].fname);