diff mbox

[v2,5/9] block: Factor bdrv_probe_all() out of find_image_format()

Message ID 1415389165-16157-6-git-send-email-kwolf@redhat.com
State New
Headers show

Commit Message

Kevin Wolf Nov. 7, 2014, 7:39 p.m. UTC 
From: Markus Armbruster <armbru@redhat.com>

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 block.c | 45 ++++++++++++++++++++++++++++++++-------------
 1 file changed, 32 insertions(+), 13 deletions(-)

Comments

Max Reitz Nov. 10, 2014, 2:47 p.m. UTC | #1 
On 2014-11-07 at 20:39, Kevin Wolf wrote:
> From: Markus Armbruster <armbru@redhat.com>
>
> Signed-off-by: Markus Armbruster <armbru@redhat.com>
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> ---
>   block.c | 45 ++++++++++++++++++++++++++++++++-------------
>   1 file changed, 32 insertions(+), 13 deletions(-)
>
> diff --git a/block.c b/block.c
> index 4b5735c..2fdc33f 100644
> --- a/block.c
> +++ b/block.c
> @@ -648,11 +648,40 @@ BlockDriver *bdrv_find_protocol(const char *filename,
>       return NULL;
>   }
>   
> +/*
> + * Guess image format by probing its contents.
> + * This is not a good idea when your image is raw (CVE-2008-2004), but
> + * we do it anyway for backward compatibility.
> + * @buf contains the image's first @buf_size bytes.
> + * @buf_size is 2048 or the image's size, whatever is smaller.

That is a funny parameter description. You should fix it in patch 6 (or 
directly here).

Anyway, as for this patch (or with the comment saying "@buf_size should 
be at least 512" or something like that):

Reviewed-by: Max Reitz <mreitz@redhat.com>
Stefan Hajnoczi Nov. 13, 2014, 10:47 a.m. UTC | #2 
On Fri, Nov 07, 2014 at 08:39:21PM +0100, Kevin Wolf wrote:
> From: Markus Armbruster <armbru@redhat.com>
> 
> Signed-off-by: Markus Armbruster <armbru@redhat.com>
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> ---
>  block.c | 45 ++++++++++++++++++++++++++++++++-------------
>  1 file changed, 32 insertions(+), 13 deletions(-)

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
diff mbox

Patch

diff --git a/block.c b/block.c
index 4b5735c..2fdc33f 100644
--- a/block.c
+++ b/block.c
@@ -648,11 +648,40 @@  BlockDriver *bdrv_find_protocol(const char *filename,
     return NULL;
 }
 
+/*
+ * Guess image format by probing its contents.
+ * This is not a good idea when your image is raw (CVE-2008-2004), but
+ * we do it anyway for backward compatibility.
+ * @buf contains the image's first @buf_size bytes.
+ * @buf_size is 2048 or the image's size, whatever is smaller.
+ * @filename is its filename.
+ * For all block drivers, call the bdrv_probe() method to get its
+ * probing score.
+ * Return the first block driver with the highest probing score.
+ */
+static BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size,
+                                   const char *filename)
+{
+    int score_max = 0, score;
+    BlockDriver *drv = NULL, *d;
+
+    QLIST_FOREACH(d, &bdrv_drivers, list) {
+        if (d->bdrv_probe) {
+            score = d->bdrv_probe(buf, buf_size, filename);
+            if (score > score_max) {
+                score_max = score;
+                drv = d;
+            }
+        }
+    }
+
+    return drv;
+}
+
 static int find_image_format(BlockDriverState *bs, const char *filename,
                              BlockDriver **pdrv, Error **errp)
 {
-    int score, score_max;
-    BlockDriver *drv1, *drv;
+    BlockDriver *drv;
     uint8_t buf[2048];
     int ret = 0;
 
@@ -675,17 +704,7 @@  static int find_image_format(BlockDriverState *bs, const char *filename,
         return ret;
     }
 
-    score_max = 0;
-    drv = NULL;
-    QLIST_FOREACH(drv1, &bdrv_drivers, list) {
-        if (drv1->bdrv_probe) {
-            score = drv1->bdrv_probe(buf, ret, filename);
-            if (score > score_max) {
-                score_max = score;
-                drv = drv1;
-            }
-        }
-    }
+    drv = bdrv_probe_all(buf, ret, filename);
     if (!drv) {
         error_setg(errp, "Could not determine image format: No compatible "
                    "driver found");