From e2b3dc25804ce3688ac69a7249323e90ae82305e Mon Sep 17 00:00:00 2001
From: Christopher Faylor <me@cgf.cx>
Date: Thu, 15 Nov 2001 03:25:52 +0000
Subject: [PATCH] * exceptions.cc: Add stdlib.h include for alloca declaration.
 * poll.cc: Ditto. * termios.cc: Ditto. * syscalls.cc (_write): Only allow
 zero length when fd is valid.

---
 winsup/cygwin/ChangeLog     | 12 +++++++++++-
 winsup/cygwin/exceptions.cc |  1 +
 winsup/cygwin/poll.cc       |  1 +
 winsup/cygwin/syscalls.cc   | 16 ++++++++++------
 winsup/cygwin/termios.cc    |  1 +
 5 files changed, 24 insertions(+), 7 deletions(-)

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 61a68933b..9c5fa545e 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,7 +1,17 @@
+2001-11-14  Christopher Faylor  <cgf@redhat.com>
+
+	* exceptions.cc: Add stdlib.h include for alloca declaration.
+	* poll.cc: Ditto.
+	* termios.cc: Ditto.
+
+2001-11-14  Christopher Faylor  <cgf@redhat.com>
+
+	* syscalls.cc (_write): Only allow zero length when fd is valid.
+
 2001-11-14  Corinna Vinschen  <corinna@vinschen.de>
 
 	* fhandler.cc (fhandler_disk_file::fstat): Add setting access time
-	and creation time to last modification time for files on filesystems 
+	and creation time to last modification time for files on filesystems
 	not supporting multiple timestamps.
 	(fhandler_disk_file::fstat_helper): Set access time and creation
 	time in incoming Windows structure instead of in stat buf to avoid
diff --git a/winsup/cygwin/exceptions.cc b/winsup/cygwin/exceptions.cc
index 560eab43c..41a1319db 100644
--- a/winsup/cygwin/exceptions.cc
+++ b/winsup/cygwin/exceptions.cc
@@ -11,6 +11,7 @@ details. */
 #include "winsup.h"
 #include <imagehlp.h>
 #include <errno.h>
+#include <stdlib.h>
 
 #include "exceptions.h"
 #include "sync.h"
diff --git a/winsup/cygwin/poll.cc b/winsup/cygwin/poll.cc
index 76f8c35dd..8b73c5afd 100644
--- a/winsup/cygwin/poll.cc
+++ b/winsup/cygwin/poll.cc
@@ -12,6 +12,7 @@
 #include <sys/time.h>
 #include <sys/poll.h>
 #include <errno.h>
+#include <stdlib.h>
 #include "security.h"
 #include "fhandler.h"
 #include "path.h"
diff --git a/winsup/cygwin/syscalls.cc b/winsup/cygwin/syscalls.cc
index 848e0e44f..d0896169b 100644
--- a/winsup/cygwin/syscalls.cc
+++ b/winsup/cygwin/syscalls.cc
@@ -355,12 +355,6 @@ _read (int fd, void *ptr, size_t len)
 extern "C" ssize_t
 _write (int fd, const void *ptr, size_t len)
 {
-  if (len == 0)
-    return 0;
-
-  if (__check_invalid_read_ptr_errno (ptr, len))
-    return -1;
-
   int res = -1;
 
   sigframe thisframe (mainthread);
@@ -368,6 +362,16 @@ _write (int fd, const void *ptr, size_t len)
   if (cfd < 0)
     goto done;
 
+  /* No further action required for len == 0 */
+  if (len == 0)
+    {
+      res = 0;
+      goto done;
+    }
+
+  if (len && __check_invalid_read_ptr_errno (ptr, len))
+    goto done;
+
   /* Could block, so let user know we at least got here.  */
   if (fd == 1 || fd == 2)
     paranoid_printf ("write (%d, %p, %d)", fd, ptr, len);
diff --git a/winsup/cygwin/termios.cc b/winsup/cygwin/termios.cc
index f5d775fae..499072f51 100644
--- a/winsup/cygwin/termios.cc
+++ b/winsup/cygwin/termios.cc
@@ -14,6 +14,7 @@ details. */
 #include "winsup.h"
 #include <errno.h>
 #include <signal.h>
+#include <stdlib.h>
 #include "cygerrno.h"
 #include "security.h"
 #include "fhandler.h"