qemu-edid: use qemu_edid_size()

So we only write out that part of the edid blob
which has been filled with data.
Also use a larger buffer for the blob.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20210427150824.638359-1-kraxel@redhat.com
Message-Id: <20210427150824.638359-2-kraxel@redhat.com>

qemu-edid.c

@@ -41,7 +41,8 @@ static void usage(FILE *out)
 int main(int argc, char *argv[])
 {
     FILE *outfile = NULL;
-    uint8_t blob[256];
+    uint8_t blob[512];
+    size_t size;
     uint32_t dpi = 100;
     int rc;
 
@@ -119,7 +120,8 @@ int main(int argc, char *argv[])
 
     memset(blob, 0, sizeof(blob));
     qemu_edid_generate(blob, sizeof(blob), &info);
-    fwrite(blob, sizeof(blob), 1, outfile);
+    size = qemu_edid_size(blob);
+    fwrite(blob, size, 1, outfile);
     fflush(outfile);
 
     exit(0);