standards/188173: O_NOFOLLOW visibility not POSIX 2008 conforming

[Jilles Tjoelker]

On Sat, Apr 05, 2014 at 11:16:07PM +0300, Konstantin Belousov wrote:
> On Tue, Apr 01, 2014 at 03:31:31PM +0000, Christian Neukirchen wrote:
> > >Fix:
> > Adjust the condition in /usr/include/sys/fcntl.h to use _POSIX_C_SOURCE >= 200809
> > 
> > #if __BSD_VISIBLE
> > #define O_NOFOLLOW      0x0100          /* don't follow symlinks */
> > #endif
> > 

> Thank you for noting this. Still, I want to formally request your
> confirmation that the following patch works for you. I only have 1003.1,
> 2013 access right now.

> diff --git a/sys/sys/fcntl.h b/sys/sys/fcntl.h
> index 3461f8b..2691449 100644
> --- a/sys/sys/fcntl.h
> +++ b/sys/sys/fcntl.h
> @@ -96,7 +96,7 @@ typedef	__pid_t		pid_t;
>  #define	O_FSYNC		0x0080		/* synchronous writes */
>  #endif
>  #define	O_SYNC		0x0080		/* POSIX synonym for O_FSYNC */
> -#if __BSD_VISIBLE
> +#if __POSIX_VISIBLE >= 200809
>  #define	O_NOFOLLOW	0x0100		/* don't follow symlinks */
>  #endif
>  #define	O_CREAT		0x0200		/* create if nonexistent */

This looks good, but I went ahead and made the other new POSIX.1-2008
things visible as well and removed redundant __BSD_VISIBLE condition
parts:

Index: sys/sys/fcntl.h
===================================================================
--- sys/sys/fcntl.h	(revision 263842)
+++ sys/sys/fcntl.h	(working copy)
@@ -96,7 +96,7 @@ typedef	__pid_t		pid_t;
 #define	O_FSYNC		0x0080		/* synchronous writes */
 #endif
 #define	O_SYNC		0x0080		/* POSIX synonym for O_FSYNC */
-#if __BSD_VISIBLE
+#if __POSIX_VISIBLE >= 200809
 #define	O_NOFOLLOW	0x0100		/* don't follow symlinks */
 #endif
 #define	O_CREAT		0x0200		/* create if nonexistent */
@@ -115,7 +115,7 @@ typedef	__pid_t		pid_t;
 #endif
 
 /* Defined by POSIX Extended API Set Part 2 */
-#if __BSD_VISIBLE
+#if __POSIX_VISIBLE >= 200809
 #define	O_DIRECTORY	0x00020000	/* Fail if not directory */
 #define	O_EXEC		0x00040000	/* Open for execute only */
 #endif
@@ -184,7 +184,7 @@ typedef	__pid_t		pid_t;
 #endif
 
 /* Defined by POSIX Extended API Set Part 2 */
-#if __BSD_VISIBLE
+#if __POSIX_VISIBLE >= 200809
 /*
  * Magic value that specify the use of the current working directory
  * to determine the target of relative file paths in the openat() and
@@ -211,7 +211,7 @@ typedef	__pid_t		pid_t;
 #define	F_SETFD		2		/* set file descriptor flags */
 #define	F_GETFL		3		/* get file status flags */
 #define	F_SETFL		4		/* set file status flags */
-#if __BSD_VISIBLE || __XSI_VISIBLE || __POSIX_VISIBLE >= 200112
+#if __XSI_VISIBLE || __POSIX_VISIBLE >= 200112
 #define	F_GETOWN	5		/* get SIGIO/SIGURG proc/pgrp */
 #define	F_SETOWN	6		/* set SIGIO/SIGURG proc/pgrp */
 #endif
@@ -229,7 +229,7 @@ typedef	__pid_t		pid_t;
 #define	F_READAHEAD	15		/* read ahead */
 #define	F_RDAHEAD	16		/* Darwin compatible read ahead */
 #endif
-#if __BSD_VISIBLE || __POSIX_VISIBLE >= 200809
+#if __POSIX_VISIBLE >= 200809
 #define	F_DUPFD_CLOEXEC	17		/* Like F_DUPFD, but FD_CLOEXEC is set */
 #endif
 #if __BSD_VISIBLE
@@ -310,10 +310,10 @@ int	fcntl(int, int, ...);
 #if __BSD_VISIBLE
 int	flock(int, int);
 #endif
-#if __BSD_VISIBLE || __POSIX_VISIBLE >= 200809
+#if __POSIX_VISIBLE >= 200809
 int	openat(int, const char *, int, ...);
 #endif
-#if __BSD_VISIBLE || __POSIX_VISIBLE >= 200112
+#if __POSIX_VISIBLE >= 200112
 int	posix_fadvise(int, off_t, off_t, int);
 int	posix_fallocate(int, off_t, off_t);
 #endif

For testing, I compiled (using -std=c99) and ran the following:

#define _POSIX_C_SOURCE 200809

#include <fcntl.h>

int
main(int argc, char **argv)
{
	if (argc != 2)
		return 2;
	int fd = open(argv[1], O_RDONLY | O_NOFOLLOW);
	if (fd == -1)
		return 1;
	return 0;
}

and likewise with #define _XOPEN_SOURCE 700 instead of #define
_POSIX_C_SOURCE 200809.

-- 
Jilles Tjoelker