native preadv/pwritev support (Christoph Hellwig)

This ties up the preadv/pwritev syscalls to qemu if they are declared in
unistd.h.  This is the case currently on at least NetBSD and OpenBSD and
will hopefully soon be the case on Linux.

Thanks to Blue Swirl and Gerd Hoffmann for the configure autodetection
of preadv/pwritev.


Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7021 c046a42c-6fe2-441c-8c8c-71466251a162

1 files changed, 17 insertions, 0 deletions

diff --git a/configure b/configure
index 15b7856..412828e 100755
--- a/configure
+++ b/configure
@@ -1108,6 +1108,19 @@ if $cc $ARCH_CFLAGS -o $TMPE $TMPC > /dev/null 2> /dev/null ; then
 fi
 
 ##########################################
+# preadv probe
+cat > $TMPC <<EOF
+#include <sys/types.h>
+#include <sys/uio.h>
+#include <unistd.h>
+int main(void) { preadv; }
+EOF
+preadv=no
+if $cc $ARCH_CFLAGS -o $TMPE $TMPC > /dev/null 2> /dev/null ; then
+  preadv=yes
+fi
+
+##########################################
 # fdt probe
 if test "$fdt" = "yes" ; then
     fdt=no
@@ -1221,6 +1234,7 @@ echo "AIO support       $aio"
 echo "Install blobs     $blobs"
 echo "KVM support       $kvm"
 echo "fdt support       $fdt"
+echo "preadv support    $preadv"
 
 if test $sdl_too_old = "yes"; then
 echo "-> Your SDL version is too old - please upgrade to have SDL support"
@@ -1522,6 +1536,9 @@ fi
 if test "$iovec" = "yes" ; then
   echo "#define HAVE_IOVEC 1" >> $config_h
 fi
+if test "$preadv" = "yes" ; then
+  echo "#define HAVE_PREADV 1" >> $config_h
+fi
 if test "$fdt" = "yes" ; then
   echo "#define HAVE_FDT 1" >> $config_h
   echo "FDT_LIBS=-lfdt" >> $config_mak