Paolo Bonzini <pbonz...@redhat.com> writes: > On 29/10/20 18:39, Paolo Bonzini wrote: >>> When @tight was set to false as it should be, absent @tight defaults >>> to false. Wrong, it should default to true. This is what breaks QMP. >> When @has_tight... > > Ah, I see what you meant here. Suggested reword: > > --------- > An optional bool member of a QAPI struct can be false, true, or absent. > The previous commit demonstrated that socket_listen() and > socket_connect() are broken for absent @tight, and indeed QMP chardev- > add also defaults absent member @tight to false instead of true. > > In C, QAPI members are represented by two fields, has_MEMBER and MEMBER. > We have: > > has_MEMBER MEMBER > false true false > true true false > absent false false/ignore > > When has_MEMBER is false, MEMBER should be set to false on write, and > ignored on read. > > For QMP, the QAPI visitors handle absent @tight by setting both > @has_tight and @tight to false. unix_listen_saddr() and > unix_connect_saddr() however use @tight only, disregarding @has_tight. > This is wrong and means that absent @tight defaults to false whereas it > should default to true. > > The same is true for @has_abstract, though @abstract defaults to > false and therefore has the same behavior for all of QMP, HMP and CLI. > Fix unix_listen_saddr() and unix_connect_saddr() to check > @has_abstract/@has_tight, and to default absent @tight to true. > > However, this is only half of the story. HMP chardev-add and CLI > -chardev so far correctly defaulted @tight to true, but defaults to > false again with the above fix for HMP and CLI. In fact, the "tight" > and "abstract" options now break completely. > > Digging deeper, we find that qemu_chr_parse_socket() also ignores > @has_tight, leaving it false when it sets @tight. That is also wrong, > but the two wrongs cancelled out. Fix qemu_chr_parse_socket() to set > @has_tight and @has_abstract; writing testcases for HMP and CLI is left > for another day. > --------- > > Apologies if the last sentence is incorrect. :)
Sold (with the table fixed as per Eric's review)!
