POSIX does not require ptsname() to set errno on failure, and
FreeBSD 8.2 leaves it unchanged.
* lib/ptsname_r.c (ptsname_r): Guarantee errno on ptsname failure.
* doc/posix-functions/ptsname.texi (ptsname): Document the issue.
Signed-off-by: Eric Blake <ebl...@redhat.com>
---
ChangeLog | 4 ++++
doc/posix-functions/ptsname.texi | 3 +++
lib/ptsname_r.c | 14 +++++++++++++-
3 files changed, 20 insertions(+), 1 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index 70172b4..d7326ef 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
2011-11-07 Eric Blake <ebl...@redhat.com>
+ ptsname_r: work around FreeBSD issue
+ * lib/ptsname_r.c (ptsname_r): Guarantee errno on ptsname failure.
+ * doc/posix-functions/ptsname.texi (ptsname): Document the issue.
+
ptsname_r: port to Solaris
* m4/ptsname_r.m4 (gl_FUNC_PTSNAME_R): Also check for ptsname.
* m4/ptsname.m4 (gl_FUNC_PTSNAME): Optimize check.
diff --git a/doc/posix-functions/ptsname.texi b/doc/posix-functions/ptsname.texi
index 2584af8..3ad5fc1 100644
--- a/doc/posix-functions/ptsname.texi
+++ b/doc/posix-functions/ptsname.texi
@@ -25,6 +25,9 @@ ptsname
This function is not thread-safe on some platforms:
Cygwin 1.7.9.
Likewise, the gnulib replacement is not thread-safe.
+@item
+As allowed by POSIX, this function does not set errno on some platforms:
+FreeBSD 8.2.
@end itemize
Note that the Gnulib module @code{ptsname_r} is a version of this
diff --git a/lib/ptsname_r.c b/lib/ptsname_r.c
index e200f34..c4b1c69 100644
--- a/lib/ptsname_r.c
+++ b/lib/ptsname_r.c
@@ -23,6 +23,8 @@
#if HAVE_PTSNAME
+# include <fcntl.h>
+
/* Store at most BUFLEN characters of the pathname of the slave pseudo
terminal associated with the master FD is open on in BUF.
Return 0 on success, otherwise an error number. */
@@ -31,15 +33,25 @@ ptsname_r (int fd, char *buf, size_t buflen)
{
/* This assumes nothing else directly calls ptsname(). */
char *name;
+ int saved_errno = errno;
if (!buf)
return errno = EINVAL;
+
+ /* Work around FreeBSD 8.2 ptsname(-1) that fails to set errno. */
+ saved_errno = errno;
+ errno = 0;
name = ptsname (fd);
if (!name)
- return errno;
+ {
+ if (!errno && fcntl (fd, F_GETFL) >= 0)
+ errno = ENOTTY;
+ return errno;
+ }
if (buflen <= strlen (name))
return errno = ERANGE;
strcpy (buf, name);
+ errno = saved_errno;
return 0;
}
--
1.7.4.4
