X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fpipe2.c;h=cd1fe56413c7048a2ce9d0f6a83a948295e9f8ef;hb=39a489fa27ab3873e0fc0f65844413f46fcb2117;hp=6ffb101f3d0ce6cdac672b2733a31ad631834257;hpb=0568a6e8985cc2ae9c57cb03fc81f5305458b7d2;p=gnulib.git

diff --git a/lib/pipe2.c b/lib/pipe2.c
index 6ffb101f3..cd1fe5641 100644
--- a/lib/pipe2.c
+++ b/lib/pipe2.c
@@ -24,7 +24,11 @@
 #include <fcntl.h>
 
 #include "binary-io.h"
-#include "nonblocking.h"
+#include "verify.h"
+
+#if GNULIB_defined_O_NONBLOCK
+# include "nonblocking.h"
+#endif
 
 #if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
 /* Native Woe32 API.  */
@@ -36,6 +40,13 @@
 int
 pipe2 (int fd[2], int flags)
 {
+  /* Mingw _pipe() corrupts fd on failure; also, if we succeed at
+     creating the pipe but later fail at changing fcntl, we want
+     to leave fd unchanged: http://austingroupbugs.net/view.php?id=467  */
+  int tmp[2];
+  tmp[0] = fd[0];
+  tmp[1] = fd[1];
+
 #if HAVE_PIPE2
 # undef pipe2
   /* Try the system call first, if it exists.  (We may be running with a glibc
@@ -66,23 +77,30 @@ pipe2 (int fd[2], int flags)
 #if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
 /* Native Woe32 API.  */
 
+  if (_pipe (fd, 4096, flags & ~O_NONBLOCK) < 0)
+    {
+      fd[0] = tmp[0];
+      fd[1] = tmp[1];
+      return -1;
+    }
+
+  /* O_NONBLOCK handling.
+     On native Windows platforms, O_NONBLOCK is defined by gnulib.  Use the
+     functions defined by the gnulib module 'nonblocking'.  */
+# if GNULIB_defined_O_NONBLOCK
   if (flags & O_NONBLOCK)
     {
-      int result = _pipe (fd, 4096, flags & ~O_NONBLOCK);
-      if (result != 0)
-        return result;
       if (set_nonblocking_flag (fd[0], true) != 0
           || set_nonblocking_flag (fd[1], true) != 0)
-        {
-          int saved_errno = errno;
-          close (fd[0]);
-          close (fd[1]);
-          result = -1;
-          errno = saved_errno;
-        }
-      return result;
+        goto fail;
     }
-  return _pipe (fd, 4096, flags);
+# else
+  {
+    verify (O_NONBLOCK == 0);
+  }
+# endif
+
+  return 0;
 
 #else
 /* Unix API.  */
@@ -94,6 +112,8 @@ pipe2 (int fd[2], int flags)
      says that initially, the O_NONBLOCK and FD_CLOEXEC flags are cleared on
      both fd[0] and fd[1].  */
 
+  /* O_NONBLOCK handling.
+     On Unix platforms, O_NONBLOCK is defined by the system.  Use fcntl().  */
   if (flags & O_NONBLOCK)
     {
       int fcntl_flags;
@@ -131,14 +151,19 @@ pipe2 (int fd[2], int flags)
 
   return 0;
 
+#endif
+
+#if GNULIB_defined_O_NONBLOCK || \
+  !((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__)
  fail:
   {
     int saved_errno = errno;
     close (fd[0]);
     close (fd[1]);
+    fd[0] = tmp[0];
+    fd[1] = tmp[1];
     errno = saved_errno;
     return -1;
   }
-
 #endif
 }