diff mbox series

[1/2] qemu-img: refactor dump_map_entry JSON format output

Message ID 20200322091117.79443-2-eyal.moscovici@oracle.com
State New
Headers show
Series Additional parameters for qemu_img map | expand

Commit Message

Eyal Moscovici March 22, 2020, 9:11 a.m. UTC 
Previously dump_map_entry identified whether we need to start a new JSON
array based on whether start address == 0. In this refactor we remove
this assumption as in following patches we will allow map to start from
an arbitrary position.

Acked-by: Mark Kanda <mark.kanda@oracle.com>
Signed-off-by: Eyal Moscovici <eyal.moscovici@oracle.com>
---
 qemu-img.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

Comments

Eric Blake April 29, 2020, 2:58 p.m. UTC | #1 
On 3/22/20 4:11 AM, Eyal Moscovici wrote:
> Previously dump_map_entry identified whether we need to start a new JSON
> array based on whether start address == 0. In this refactor we remove
> this assumption as in following patches we will allow map to start from
> an arbitrary position.
> 
> Acked-by: Mark Kanda <mark.kanda@oracle.com>
> Signed-off-by: Eyal Moscovici <eyal.moscovici@oracle.com>
> ---
>   qemu-img.c | 12 ++++++++----
>   1 file changed, 8 insertions(+), 4 deletions(-)
> 

> @@ -2871,8 +2870,8 @@ static int dump_map_entry(OutputFormat output_format, MapEntry *e,
>           }
>           putchar('}');
>   
> -        if (!next) {
> -            printf("]\n");
> +        if (next) {
> +            printf(",\n");

As long as you're touching this, puts(",") is slightly more efficient 
than printf().  But what you have is not wrong.

Reviewed-by: Eric Blake <eblake@redhat.com>
Eyal Moscovici May 6, 2020, 9:55 a.m. UTC | #2 
On 29/04/2020, 17:58, "Eric Blake" <eblake@redhat.com> wrote:

    On 3/22/20 4:11 AM, Eyal Moscovici wrote:
    > Previously dump_map_entry identified whether we need to start a new JSON
    > array based on whether start address == 0. In this refactor we remove
    > this assumption as in following patches we will allow map to start from
    > an arbitrary position.
    > 
    > Acked-by: Mark Kanda <mark.kanda@oracle.com>
    > Signed-off-by: Eyal Moscovici <eyal.moscovici@oracle.com>
    > ---
    >   qemu-img.c | 12 ++++++++----
    >   1 file changed, 8 insertions(+), 4 deletions(-)
    > 
    
    > @@ -2871,8 +2870,8 @@ static int dump_map_entry(OutputFormat output_format, MapEntry *e,
    >           }
    >           putchar('}');
    >   
    > -        if (!next) {
    > -            printf("]\n");
    > +        if (next) {
    > +            printf(",\n");
    
    As long as you're touching this, puts(",") is slightly more efficient 
    than printf().  But what you have is not wrong.

Thanks, will fix.
    
    Reviewed-by: Eric Blake <eblake@redhat.com>
    
    -- 
    Eric Blake, Principal Software Engineer
    Red Hat, Inc.           +1-919-301-3226
    Virtualization:  qemu.org | libvirt.org
diff mbox series

Patch

diff --git a/qemu-img.c b/qemu-img.c
index afddf33f08..9cf8576217 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -2860,9 +2860,8 @@  static int dump_map_entry(OutputFormat output_format, MapEntry *e,
         }
         break;
     case OFORMAT_JSON:
-        printf("%s{ \"start\": %"PRId64", \"length\": %"PRId64","
+        printf("{ \"start\": %"PRId64", \"length\": %"PRId64","
                " \"depth\": %"PRId64", \"zero\": %s, \"data\": %s",
-               (e->start == 0 ? "[" : ",\n"),
                e->start, e->length, e->depth,
                e->zero ? "true" : "false",
                e->data ? "true" : "false");
@@ -2871,8 +2870,8 @@  static int dump_map_entry(OutputFormat output_format, MapEntry *e,
         }
         putchar('}');
 
-        if (!next) {
-            printf("]\n");
+        if (next) {
+            printf(",\n");
         }
         break;
     }
@@ -3047,6 +3046,8 @@  static int img_map(int argc, char **argv)
 
     if (output_format == OFORMAT_HUMAN) {
         printf("%-16s%-16s%-16s%s\n", "Offset", "Length", "Mapped to", "File");
+    } else if (output_format == OFORMAT_JSON) {
+        printf("[");
     }
 
     length = blk_getlength(blk);
@@ -3078,6 +3079,9 @@  static int img_map(int argc, char **argv)
     }
 
     ret = dump_map_entry(output_format, &curr, NULL);
+    if (output_format == OFORMAT_JSON) {
+        printf("]\n");
+    }
 
 out:
     blk_unref(blk);