X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Ffull-write.c;h=f21e4791aeaa9d3895e4bc9e32ada6325c371053;hb=ef8e4e5cfec5367d1c3c3aedf15408371de20f6d;hp=1feb2f7431145cb011b811db7a3ae8b25f4650f2;hpb=18449184812052eac4eb70758a93076ce3dcdf89;p=gnulib.git

diff --git a/lib/full-write.c b/lib/full-write.c
index 1feb2f743..f21e4791a 100644
--- a/lib/full-write.c
+++ b/lib/full-write.c
@@ -1,5 +1,7 @@
-/* full-write.c -- an interface to write that retries after interrupts
-   Copyright (C) 1993, 1994, 1997, 1998, 2000 Free Software Foundation, Inc.
+/* An interface to write() that writes all it is asked to write.
+
+   Copyright (C) 1993, 1994, 1997, 1998, 1999, 2000, 2001, 2002 Free Software
+   Foundation, Inc.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -13,54 +15,52 @@
 
    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software Foundation,
-   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
-
-   Copied largely from GNU C's cccp.c.
-   */
+   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
 
 #if HAVE_CONFIG_H
 # include <config.h>
 #endif
 
-#include <sys/types.h>
-
-#if HAVE_UNISTD_H
-# include <unistd.h>
-#endif
+/* Specification.  */
+#include "full-write.h"
 
 #include <errno.h>
 #ifndef errno
 extern int errno;
 #endif
 
-/* Write LEN bytes at PTR to descriptor DESC, retrying if interrupted.
-   Return LEN upon success, write's (negative) error code otherwise.  */
+#include "safe-write.h"
 
-int
-full_write (int desc, const char *ptr, size_t len)
+/* Write COUNT bytes at BUF to descriptor FD, retrying if interrupted
+   or if partial writes occur.  Return the number of bytes successfully
+   written, setting errno if that is less than COUNT.  */
+size_t
+full_write (int fd, const void *buf, size_t count)
 {
-  int total_written;
+  size_t total_written = 0;
 
-  total_written = 0;
-  while (len > 0)
+  if (count > 0)
     {
-      int written = write (desc, ptr, len);
-      /* write on an old Slackware Linux 1.2.13 returns zero when
-	 I try to write more data than there is room on a floppy disk.
-	 This puts dd into an infinite loop.  Reproduce with
-	 dd if=/dev/zero of=/dev/fd0.  If you have this problem,
-	 consider upgrading to a newer kernel.  */
-      if (written < 0)
+      const char *ptr = buf;
+
+      do
 	{
-#ifdef EINTR
-	  if (errno == EINTR)
-	    continue;
-#endif
-	  return written;
+	  size_t written = safe_write (fd, ptr, count);
+	  if (written == (size_t)-1)
+	    break;
+	  if (written == 0)
+	    {
+	      /* Some buggy drivers return 0 when you fall off a device's
+		 end.  (Example: Linux 1.2.13 on /dev/fd0.)  */
+	      errno = ENOSPC;
+	      break;
+	    }
+	  total_written += written;
+	  ptr += written;
+	  count -= written;
 	}
-      total_written += written;
-      ptr += written;
-      len -= written;
+      while (count > 0);
     }
+
   return total_written;
 }