git: 89e3d5671ba1 - main - bsnmpclient(3): make it thread-safe

[Konstantin Belousov]

On Tue, Dec 29, 2020 at 03:11:55PM +0000, Jessica Clarke wrote:
> On 29 Dec 2020, at 15:00, Edward Tomasz Napierala <trasz at FreeBSD.org> wrote:
> > diff --git a/contrib/bsnmp/lib/snmpclient.c b/contrib/bsnmp/lib/snmpclient.c
> > index c22d8e125a14..e49105918416 100644
> > --- a/contrib/bsnmp/lib/snmpclient.c
> > +++ b/contrib/bsnmp/lib/snmpclient.c
> > @@ -71,7 +71,7 @@
> > #define	DEBUG_PARSE	0
> > 
> > /* global context */
> > -struct snmp_client snmp_client;
> > +__thread struct snmp_client snmp_client;
> 
> That comment is no longer true.
> 
> > /* List of all outstanding requests */
> > struct sent_pdu {
> > @@ -86,7 +86,7 @@ struct sent_pdu {
> > };
> > LIST_HEAD(sent_pdu_list, sent_pdu);
> > 
> > -static struct sent_pdu_list sent_pdus;
> > +__thread static struct sent_pdu_list sent_pdus;
> > 
> > /*
> >  * Prototype table entry. All C-structure produced by the table function must
> > diff --git a/contrib/bsnmp/lib/snmpclient.h b/contrib/bsnmp/lib/snmpclient.h
> > index a19bdb2ea653..1bc3780de038 100644
> > --- a/contrib/bsnmp/lib/snmpclient.h
> > +++ b/contrib/bsnmp/lib/snmpclient.h
> > @@ -114,7 +114,7 @@ struct snmp_client {
> > };
> > 
> > /* the global context */
> > -extern struct snmp_client snmp_client;
> > +extern __thread struct snmp_client snmp_client;
> 
> Ditto.
> 
> Is there really a documented requirement for everything to be called
> from the same thread? I can see consumers of the library that already
> use proper locking breaking because of this.

So this variable is supposed to be used by consumers ?
The change requires the library version bump, at least.
I suppose libsnmpclient does not use symbol versioning ?