[libvirt] [PATCH][RFC] helper of copy-storage-* features

[li guang]

在 2012-10-18四的 01:03 -0500，Doug Goldstein写道：
> On Thu, Oct 18, 2012 at 12:47 AM, li guang <lig.fnst at cn.fujitsu.com> wrote:
> > 在 2012-10-17三的 21:50 -0500，Doug Goldstein写道：
> >> On Sun, Oct 14, 2012 at 9:48 PM, liguang <lig.fnst at cn.fujitsu.com> wrote:
> >> > help to create disk images copy-storage-* required,
> >> > try to do non-shared migration without bothering to
> >> > create disk images at target by hand.
> >> >
> >> > consider this situation:
> >> > 1. non-shared migration
> >> >    virsh migrate --copy-storage-all ...
> >> > 2. migration fails
> >> > 3. create disk images required
> >> >    qemu-img create ...
> >> > 4  migration run smoothly
> >> > so, try do remove step 2, 3, 4
> >> >
> >> > +char *virDirOfFile(const char *file)
> >> > +{
> >> > +    char *p, *tmp;
> >> > +
> >> > +    if (file == NULL)
> >> > +        return NULL;
> >> > +    if ((tmp = strdup(file)) == NULL)
> >> > +        return NULL;
> >> > +    if ((p = strrchr(file, '/')) == NULL)
> >> > +        return getcwd(tmp, strlen(file));
> >> > +    if (strlen(p) == 0)
> >> > +        return NULL;
> >> > +    tmp[strlen(file) - strlen(p)] = '\0';
> >> > +
> >> > +    return tmp;
> >> > +}
> >>
> >> Eric probably knows better than I do but it seems like we can probably
> >> pull in dirname() from gnulib for this rather than implementing our
> >> own version.
> >>
> >
> > maybe, but dirname has its own known issues(e.g. for old version glibc,
> > dirname will "generate a segfault if given a NULL argument"), so I
> > try to choose a loosely implementation.
> > but, if libvirt cares nothing about these tiny issues, I'd like
> > to choose dirname.
> 
> That's why I'm suggesting to use dirname from gnulib, which fixes
> several of those issues. Additionally the implementation above
> wouldn't work on Windows, not that we currently build the libvirtd on
> Windows but if the function was used in the future the function would
> have to be fixed.

glad to hear that gnulib's dirname is a fixed version,
if so, I'd like to use it instead of my silly re-implementation.
Thanks!

> 
> >
> >> > diff --git a/src/util/util.h b/src/util/util.h
> >> > index 4316ab1..255b7b2 100644
> >> > --- a/src/util/util.h
> >> > +++ b/src/util/util.h
> >> > @@ -114,6 +114,7 @@ enum {
> >> >  };
> >> >  int virDirCreate(const char *path, mode_t mode, uid_t uid, gid_t gid,
> >> >                   unsigned int flags) ATTRIBUTE_RETURN_CHECK;
> >> > +char *virDirOfFile(const char *file) ATTRIBUTE_RETURN_CHECK;
> >> >  int virFileMakePath(const char *path) ATTRIBUTE_RETURN_CHECK;
> >> >  int virFileMakePathWithMode(const char *path,
> >> >                              mode_t mode) ATTRIBUTE_RETURN_CHECK;
> >> > --
> >> > 1.7.2.5
> >> >
> >> > --
> >> > libvir-list mailing list
> >> > libvir-list at redhat.com
> >> > https://www.redhat.com/mailman/listinfo/libvir-list
> >>
> >>
> >>
> >
> > --
> > liguang    lig.fnst at cn.fujitsu.com
> > FNST linux kernel team
> >
> 

-- 
liguang    lig.fnst at cn.fujitsu.com
FNST linux kernel team