iotests/106, 214, 308: Read only one size line

These tests read size information (sometimes disk size, sometimes
virtual size) from qemu-img info's output.  Once qemu-img starts
printing info about child nodes, we are going to see multiple instances
of that per image, but these tests are only interested in the first one,
so use "head -n 1" to get it.

Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220620162704.80987-11-hreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

tests/qemu-iotests/106

@@ -66,7 +66,7 @@ for create_mode in off falloc full; do
             expected_size=$((expected_size + $GROWTH_SIZE))
         fi
 
-        actual_size=$($QEMU_IMG info -f "$IMGFMT" "$TEST_IMG" | grep 'disk size')
+        actual_size=$($QEMU_IMG info -f "$IMGFMT" "$TEST_IMG" | grep 'disk size' | head -n 1)
         actual_size=$(echo "$actual_size" | sed -e 's/^[^0-9]*\([0-9]\+\).*$/\1/')
 
         # The actual size may exceed the expected size, depending on the file
@@ -105,7 +105,7 @@ for growth_mode in falloc full; do
     _make_test_img -o "extent_size_hint=0" 2G
     $QEMU_IMG resize -f "$IMGFMT" --preallocation=$growth_mode "$TEST_IMG" +${GROWTH_SIZE}K
 
-    actual_size=$($QEMU_IMG info -f "$IMGFMT" "$TEST_IMG" | grep 'disk size')
+    actual_size=$($QEMU_IMG info -f "$IMGFMT" "$TEST_IMG" | grep 'disk size' | head -n 1)
     actual_size=$(echo "$actual_size" | sed -e 's/^[^0-9]*\([0-9]\+\).*$/\1/')
 
     if [ $actual_size -lt $GROWTH_SIZE ]; then

tests/qemu-iotests/214

@@ -102,7 +102,8 @@ let data_size="8 * $cluster_size"
 $QEMU_IO -c "write -P 0xaa 0 $data_size" "$TEST_IMG" \
          2>&1 | _filter_qemu_io | _filter_testdir
 sizeA=$($QEMU_IMG info --output=json "$TEST_IMG" |
-        sed -n '/"actual-size":/ s/[^0-9]//gp')
+        sed -n '/"actual-size":/ s/[^0-9]//gp' |
+        head -n 1)
 
 _make_test_img 2M -o cluster_size=$cluster_size
 echo "Write compressed data:"
@@ -124,7 +125,8 @@ $QEMU_IO -c "write -P 0xcc $offset $data_size" "json:{\
                           _filter_qemu_io | _filter_testdir
 
 sizeB=$($QEMU_IMG info --output=json "$TEST_IMG" |
-        sed -n '/"actual-size":/ s/[^0-9]//gp')
+        sed -n '/"actual-size":/ s/[^0-9]//gp' |
+        head -n 1)
 
 if [ $sizeA -lt $sizeB ]
 then

tests/qemu-iotests/308

@@ -217,12 +217,12 @@ echo
 echo '=== Remove export ==='
 
 # Double-check that $EXT_MP appears as a non-empty file (the raw image)
-$QEMU_IMG info -f raw "$EXT_MP" | grep 'virtual size'
+$QEMU_IMG info -f raw "$EXT_MP" | grep 'virtual size' | head -n 1
 
 fuse_export_del 'export-mp'
 
 # See that the file appears empty again
-$QEMU_IMG info -f raw "$EXT_MP" | grep 'virtual size'
+$QEMU_IMG info -f raw "$EXT_MP" | grep 'virtual size' | head -n 1
 
 echo
 echo '=== Writable export ==='