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-rw-r--r--sysdeps/mach/hurd/sendfile.c60
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diff --git a/sysdeps/mach/hurd/sendfile.c b/sysdeps/mach/hurd/sendfile.c
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+++ b/sysdeps/mach/hurd/sendfile.c
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+/* sendfile -- copy data directly from one file descriptor to another
+   Copyright (C) 2002 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <sys/sendfile.h>
+#include <hurd.h>
+#include <hurd/fd.h>
+#include <sys/mman.h>
+
+/* Send COUNT bytes from file associated with IN_FD starting at OFFSET to
+   descriptor OUT_FD.  */
+ssize_t
+sendfile (int out_fd, int in_fd, off_t *offset, size_t count)
+{
+  /* We just do a vanilla io_read followed by a vanilla io_write here.
+     In theory the IN_FD filesystem can return us out-of-line data that
+     we then send out-of-line to the OUT_FD filesystem and no copying
+     takes place until those pages need to be flushed or packaged by
+     that filesystem (e.g. packetized by a network socket).  However,
+     we momentarily consume COUNT bytes of our local address space,
+     which might blow if it's huge or address space is real tight.  */
+
+  char *data = 0;
+  size_t datalen = 0;
+  error_t err = HURD_DPORT_USE (in_fd,
+				__io_read (port, &data, &datalen,
+					   offset ? *offset : (off_t) -1,
+					   count));
+  if (err == 0)
+    {
+      size_t nwrote;
+      if (datalen == 0)
+	return 0;
+      err = HURD_DPORT_USE (out_fd, __io_write (port, data, datalen,
+						(off_t) -1, &nwrote));
+      munmap (data, datalen);
+      if (err == 0)
+	{
+	  if (offset)
+	    *offset += datalen;
+	  return nwrote;
+	}
+    }
+  return __hurd_fail (err);
+}