Fsprotocone():
qopen() and qbypass() can fail and return nil, so make sure
the connection was not partially created by checking if read
and write queues have been setup by the protocol create hanler.
on error, free any resources of the partial connection and
error out.
netlogopen(): check malloc() error.
the initial fontresize() might fail but its error code is ignored
potentially leaving f->cacheimage == nil. make sure we call
fontresize() in loadchar() when theres no cacheimage and check the
return value to avoid nil pointer dereference.
instead of trying to resize the segment (which will not work when
the kernel picks the address as it will allocate right before
the base of the topmost segment), we create the mux segment with the
maximum size needed (arround 1.4MB) for OPEN_MAX filedescriptors.
buf slots will be reused and slots get demand paged once used.
1 the config string was grabbed Aoehsz too far into the packet due to using the wrong pointer to start.
2 never accept a response with tag Tmgmt or Tfree.
3 defend against "malicious" responses; ones with a response Aoehdr.type != request Aoehdr.type. this previously could
cause the initiator to crash.
4 vendor commands were improperly filtered out.
the integer division instructions are emulated with _div()
function patched in by 5l which does not handle conditional
execution. so do not optimize away the branch in that case.
specifing -d on the command line now only disables synchronous
drawing events.
- use threaded mouse and keyboard to allow for asynchronous
receoption of quit messages. this allows plot to exit before drawing
is completed. for programs like mapdemo, this is important.
there were two things that needed to get fixed as a result
- replace fprint(2, ...); exits("bad"); with sysfatal. also get rid
of stdio.
- dpoint needed a mach-dependentent (sic) version. otherwise
points on a resized screen will not be properly placed.
Charles Forsyth described the problem below in:
http://9fans.net/archive/2013/04/190
In a few cases, the kernel will use pprint to put a diagnostic on the
standard error (file descriptor 2). One of those is a warning that the
process has used more than 100 file descriptors. That message is possibly
obsolete and could be removed, but there are others, such as notifying an
uncaught trap that are probably helpful to make visible. In any case, as
things stand, a busy exportfs might have many file descriptors open,
provoking the diagnostic. Unfortunately, aux/listen and aux/listen1 connect
file descriptor 2 to the incoming network connection. If the connection's
protocol is not a simple, unstructured, textual one, diagnostics on the
standard error will cause confusion, in particular to devmnt.c if 9p is used.
/rc/bin/service files that start applications that run special protocols
might want to redirect file descriptor 2; alternatively, perhaps aux/listen
shouldn't redirect fd 2 by default: the few commands that do connect the remote
user to shells, or equivalent, including telnetd and sshd could dup 1 to 2
when that was sensible.