Signed-off-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/106     | 24 ++++++++++++++++++++++++
 tests/qemu-iotests/106.out | 10 ++++++++++
 2 files changed, 34 insertions(+)

diff --git a/tests/qemu-iotests/106 b/tests/qemu-iotests/106
index bfe71f4e60..5e51f88a78 100755
--- a/tests/qemu-iotests/106
+++ b/tests/qemu-iotests/106
@@ -86,6 +86,30 @@ for growth_mode in falloc full off; do
     $QEMU_IMG resize -f "$IMGFMT" --shrink --preallocation=$growth_mode "$TEST_IMG" -${GROWTH_SIZE}K
 done
 
+echo
+echo '=== Testing image growth on 2G empty image ==='
+
+for growth_mode in falloc full; do
+    echo
+    echo "--- growth_mode=$growth_mode ---"
+
+    # Maybe we want to do an lseek() to the end of the file before the
+    # preallocation; if the file has a length of 2 GB, that would
+    # return an integer that overflows to negative when put into a
+    # plain int.  We should use the correct type for the result, and
+    # this tests we do.
+
+    _make_test_img 2G
+    $QEMU_IMG resize -f "$IMGFMT" --preallocation=$growth_mode "$TEST_IMG" +${GROWTH_SIZE}K
+
+    actual_size=$($QEMU_IMG info -f "$IMGFMT" "$TEST_IMG" | grep 'disk size')
+    actual_size=$(echo "$actual_size" | sed -e 's/^[^0-9]*\([0-9]\+\).*$/\1/')
+
+    if [ $actual_size -lt $GROWTH_SIZE ]; then
+        echo "ERROR: Image should have at least ${GROWTH_SIZE}K, but has ${actual_size}K"
+    fi
+done
+
 # success, all done
 echo '*** done'
 rm -f $seq.full
diff --git a/tests/qemu-iotests/106.out b/tests/qemu-iotests/106.out
index 0a42312301..c459957660 100644
--- a/tests/qemu-iotests/106.out
+++ b/tests/qemu-iotests/106.out
@@ -47,4 +47,14 @@ qemu-img: Preallocation can only be used for growing images
 
 --- growth_mode=off ---
 Image resized.
+
+=== Testing image growth on 2G empty image ===
+
+--- growth_mode=falloc ---
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=2147483648
+Image resized.
+
+--- growth_mode=full ---
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=2147483648
+Image resized.
 *** done
-- 
2.14.3

On Wed, Feb 28, 2018 at 02:13:15PM +0100, Max Reitz wrote:
> Signed-off-by: Max Reitz <mreitz@redhat.com>
> ---
>  tests/qemu-iotests/106     | 24 ++++++++++++++++++++++++
>  tests/qemu-iotests/106.out | 10 ++++++++++
>  2 files changed, 34 insertions(+)
> 
> diff --git a/tests/qemu-iotests/106 b/tests/qemu-iotests/106
> index bfe71f4e60..5e51f88a78 100755
> --- a/tests/qemu-iotests/106
> +++ b/tests/qemu-iotests/106
> @@ -86,6 +86,30 @@ for growth_mode in falloc full off; do
>      $QEMU_IMG resize -f "$IMGFMT" --shrink --preallocation=$growth_mode "$TEST_IMG" -${GROWTH_SIZE}K
>  done
>  
> +echo
> +echo '=== Testing image growth on 2G empty image ==='
> +
> +for growth_mode in falloc full; do
> +    echo
> +    echo "--- growth_mode=$growth_mode ---"
> +
> +    # Maybe we want to do an lseek() to the end of the file before the
> +    # preallocation; if the file has a length of 2 GB, that would
> +    # return an integer that overflows to negative when put into a
> +    # plain int.  We should use the correct type for the result, and
> +    # this tests we do.
> +
> +    _make_test_img 2G
> +    $QEMU_IMG resize -f "$IMGFMT" --preallocation=$growth_mode "$TEST_IMG" +${GROWTH_SIZE}K
> +
> +    actual_size=$($QEMU_IMG info -f "$IMGFMT" "$TEST_IMG" | grep 'disk size')
> +    actual_size=$(echo "$actual_size" | sed -e 's/^[^0-9]*\([0-9]\+\).*$/\1/')
> +
> +    if [ $actual_size -lt $GROWTH_SIZE ]; then
> +        echo "ERROR: Image should have at least ${GROWTH_SIZE}K, but has ${actual_size}K"
> +    fi
> +done
> +
>  # success, all done
>  echo '*** done'
>  rm -f $seq.full
> diff --git a/tests/qemu-iotests/106.out b/tests/qemu-iotests/106.out
> index 0a42312301..c459957660 100644
> --- a/tests/qemu-iotests/106.out
> +++ b/tests/qemu-iotests/106.out
> @@ -47,4 +47,14 @@ qemu-img: Preallocation can only be used for growing images
>  
>  --- growth_mode=off ---
>  Image resized.
> +
> +=== Testing image growth on 2G empty image ===
> +
> +--- growth_mode=falloc ---
> +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=2147483648
> +Image resized.
> +
> +--- growth_mode=full ---
> +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=2147483648
> +Image resized.
>  *** done

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>


Regards,
Daniel
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