[Qemu-devel] [PATCH v2 14/14] qemu-img: Use new JSON output formatter

[Eric Blake <eblake@redhat.com>]

Now that we can pretty-print straight to JSON from a visitor,
we can eliminate the temporary conversion into QObject inside
qemu-img.

The changes to qemu-iotests 043 expected output demonstrates
the fact that output is now done in qapi declaration order,
rather than QDict hash order.

Signed-off-by: Eric Blake <eblake@redhat.com>

---
v2: Drop RFC, adjust expected output of 043; rebase to 'name' motion

Overlaps with Fam's qemu-img edits, although he has expressed
interest in getting this one in first.
https://lists.gnu.org/archive/html/qemu-devel/2015-12/msg01756.html
https://lists.gnu.org/archive/html/qemu-devel/2015-12/msg01806.html
---
 qemu-img.c                 | 69 +++++++++++++++++++---------------------------
 tests/qemu-iotests/043.out | 22 +++++++--------
 2 files changed, 40 insertions(+), 51 deletions(-)

diff --git a/qemu-img.c b/qemu-img.c
index d9a2c74..59d3944 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -22,9 +22,9 @@
  * THE SOFTWARE.
  */
 #include "qapi-visit.h"
-#include "qapi/qmp-output-visitor.h"
+#include "qapi/json-output-visitor.h"
 #include "qapi/qmp/qerror.h"
-#include "qapi/qmp/qobject-json.h"
+#include "qapi/qmp/qstring.h"
 #include "qemu-common.h"
 #include "qemu/option.h"
 #include "qemu/error-report.h"
@@ -375,19 +375,15 @@ fail:

 static void dump_json_image_check(ImageCheck *check, bool quiet)
 {
-    Error *local_err = NULL;
-    QString *str;
-    QmpOutputVisitor *ov = qmp_output_visitor_new();
-    QObject *obj;
-    visit_type_ImageCheck(qmp_output_get_visitor(ov), NULL, &check,
-                          &local_err);
-    obj = qmp_output_get_qobject(ov);
-    str = qobject_to_json_pretty(obj);
-    assert(str != NULL);
-    qprintf(quiet, "%s\n", qstring_get_str(str));
-    qobject_decref(obj);
-    qmp_output_visitor_cleanup(ov);
-    QDECREF(str);
+    char *str;
+    JsonOutputVisitor *ov = json_output_visitor_new(true);
+    visit_type_ImageCheck(json_output_get_visitor(ov), NULL,
+                          &check, &error_abort);
+    str = json_output_get_string(ov);
+    assert(str);
+    qprintf(quiet, "%s\n", str);
+    g_free(str);
+    json_output_visitor_cleanup(ov);
 }

 static void dump_human_image_check(ImageCheck *check, bool quiet)
@@ -1926,35 +1922,28 @@ static void dump_snapshots(BlockDriverState *bs)

 static void dump_json_image_info_list(ImageInfoList *list)
 {
-    Error *local_err = NULL;
-    QString *str;
-    QmpOutputVisitor *ov = qmp_output_visitor_new();
-    QObject *obj;
-    visit_type_ImageInfoList(qmp_output_get_visitor(ov), NULL, &list,
-                             &local_err);
-    obj = qmp_output_get_qobject(ov);
-    str = qobject_to_json_pretty(obj);
-    assert(str != NULL);
-    printf("%s\n", qstring_get_str(str));
-    qobject_decref(obj);
-    qmp_output_visitor_cleanup(ov);
-    QDECREF(str);
+    char *str;
+    JsonOutputVisitor *ov = json_output_visitor_new(true);
+    visit_type_ImageInfoList(json_output_get_visitor(ov), NULL,
+                             &list, &error_abort);
+    str = json_output_get_string(ov);
+    assert(str);
+    printf("%s\n", str);
+    json_output_visitor_cleanup(ov);
+    g_free(str);
 }

 static void dump_json_image_info(ImageInfo *info)
 {
-    Error *local_err = NULL;
-    QString *str;
-    QmpOutputVisitor *ov = qmp_output_visitor_new();
-    QObject *obj;
-    visit_type_ImageInfo(qmp_output_get_visitor(ov), NULL, &info, &local_err);
-    obj = qmp_output_get_qobject(ov);
-    str = qobject_to_json_pretty(obj);
-    assert(str != NULL);
-    printf("%s\n", qstring_get_str(str));
-    qobject_decref(obj);
-    qmp_output_visitor_cleanup(ov);
-    QDECREF(str);
+    char *str;
+    JsonOutputVisitor *ov = json_output_visitor_new(true);
+    visit_type_ImageInfo(json_output_get_visitor(ov), NULL, &info,
+                         &error_abort);
+    str = json_output_get_string(ov);
+    assert(str);
+    printf("%s\n", str);
+    json_output_visitor_cleanup(ov);
+    g_free(str);
 }

 static void dump_human_image_info_list(ImageInfoList *list)
diff --git a/tests/qemu-iotests/043.out b/tests/qemu-iotests/043.out
index b37d2a3..41697a2 100644
--- a/tests/qemu-iotests/043.out
+++ b/tests/qemu-iotests/043.out
@@ -40,29 +40,29 @@ cluster_size: 65536
 == finite chain of length 3 (json) ==
 [
     {
-        "virtual-size": 134217728,
         "filename": "TEST_DIR/t.IMGFMT",
-        "cluster-size": 65536,
         "format": "IMGFMT",
-        "full-backing-filename": "TEST_DIR/t.IMGFMT.2.base",
+        "dirty-flag": false,
+        "virtual-size": 134217728,
+        "cluster-size": 65536,
         "backing-filename": "TEST_DIR/t.IMGFMT.2.base",
-        "dirty-flag": false
+        "full-backing-filename": "TEST_DIR/t.IMGFMT.2.base",
     },
     {
-        "virtual-size": 134217728,
         "filename": "TEST_DIR/t.IMGFMT.2.base",
-        "cluster-size": 65536,
         "format": "IMGFMT",
-        "full-backing-filename": "TEST_DIR/t.IMGFMT.1.base",
+        "dirty-flag": false,
+        "virtual-size": 134217728,
+        "cluster-size": 65536,
         "backing-filename": "TEST_DIR/t.IMGFMT.1.base",
-        "dirty-flag": false
+        "full-backing-filename": "TEST_DIR/t.IMGFMT.1.base",
     },
     {
-        "virtual-size": 134217728,
         "filename": "TEST_DIR/t.IMGFMT.1.base",
-        "cluster-size": 65536,
         "format": "IMGFMT",
-        "dirty-flag": false
+        "dirty-flag": false,
+        "virtual-size": 134217728,
+        "cluster-size": 65536,
     }
 ]
 *** done
-- 
2.4.3