Re: [Qemu-devel] [PATCH v2 1/4] Add Error **errp for xen_host_pci_device_get()

[Cao jin]

On 01/04/2016 11:15 PM, Stefano Stabellini wrote:
On Sun, 27 Dec 2015, Cao jin wrote:
To catch the error msg. Also modify the caller

Signed-off-by: Cao jin <caoj.f...@cn.fujitsu.com>

This looks much better, thanks.


[...]

-int xen_host_pci_device_get(XenHostPCIDevice *d, uint16_t domain,
-                            uint8_t bus, uint8_t dev, uint8_t func)
+void xen_host_pci_device_get(XenHostPCIDevice *d, uint16_t domain,
+                            uint8_t bus, uint8_t dev, uint8_t func,
+                            Error **errp)
  {
      unsigned int v;
-    int rc = 0;

      d->config_fd = -1;
      d->domain = domain;
@@ -353,43 +360,48 @@ int xen_host_pci_device_get(XenHostPCIDevice *d, uint16_t 
domain,
      d->dev = dev;
      d->func = func;

-    rc = xen_host_pci_config_open(d);
-    if (rc) {
+    xen_host_pci_config_open(d, errp);
+    if (*errp) {

I think that errp could be NULL, therefore the right way to do this is:

     Error *err = NULL;
     foo(arg, &err);
     if (err) {
         handle the error...
         error_propagate(errp, err);
     }

see the comment at the beginning of include/qapi/error.h.


Thanks for reminding, I didn`t see the comment of error.h before, now I 
am aware why lots of people like the style you mentioned. Will fix it in 
next version, also the comments in other patch.

[...]

--
Yours Sincerely,

Cao jin