Opening a /srv file sets the close-on-exec flag on the
shared channel breaking the exportfs openmount() hack.
The devsrv tries to prevent posting a channel with the
close-on-exec or remove-on-close flags. but nothing
currently prevents this poisoning on open.
Until this gets fixed in eigther exportfs or devsrv,
i'll back out the changes that could have potential side
effects like this.
a deadlock has been observed with samterm (thanks burnzez),
that shows the mouse ioproc being stuck in sending on the
resize channel, while the mouse consumer is stuck in a
readmouse() loop wanting a rectangle to be drawn by the
user:
recv(v=0x42df50)+0x28 /sys/src/libthread/channel.c:321
readmouse(mc=0x42df50)+0x54 /sys/src/libdraw/mouse.c:34
getrect(.ret=0x41bce0,but=0x4,mc=0x42df50)+0x62 /sys/src/libdraw/getrect.c:49
r=0x41bc70
rc=0x41bc70
getr(rp=0x41bce0)+0x24 /sys/src/cmd/samterm/main.c:244
p=0x6b000004f6
r=0x2
sweeptext(new=0x0,tag=0x2d)+0x12 /sys/src/cmd/samterm/menu.c:208
r=0x2
t=0x42df50
inmesg(type=0x2,count=0x2)+0x1ab /sys/src/cmd/samterm/mesg.c:136
m=0x10000002d
l=0x2d00001b00
i=0x43829000000001
t=0x438290
lp=0x42e050
rcv()+0x7a /sys/src/cmd/samterm/mesg.c:77
threadmain(argv=0x7ffffeffef90)+0x173 /sys/src/cmd/samterm/main.c:63
so avoid blocking in the mouse ioproc by using nbsend()
instead of send() for writing to the resize channel.
assigning the expression value to a temporary variable in
BPSHORT() and BPLONG() saves arround 2K of text in rio on
arm and arround 1K on amd64.
loadchar(): use the passed in "h" as the char index instead
of recomputing it from c-f->cache. dont recompute wid.
cachechars(): do cache lookup and find oldest entry in a
single loop pass.
/n/bugs/open/libdrawfont.c_buffer_overflow
http://bugs.9front.org/open/libdrawfont.c_buffer_overflow/readmeray@raylai.com
Hi all,
In plan9port this bug keeps crashing mc when I run lc in a directory with Chinese characters. This is a diff from OpenBSD but it should apply cleanly to the various plan9 sources.
The code is basically trying to do a realloc (I guess realloc wasn't available back then?) but it copies too much from the original buffer.
Since realloc is available, just use it. If realloc isn't available outside plan9port (I haven't checked) the memmove line should be changed from:
memmove(f->subf, of, (f->nsubf+DSUBF)*sizeof *subf);
to:
memmove(f->subf, of, f->nsubf*sizeof *subf);
I hope this is helpful.
Ray
- remove redundant flushimage() calls before readmouse()
- remove flushimage() calls for allocimage(),freeimage() and originwindow()
this is experimental. it will break allocimage() error handling unless the
caller does explicit flushimage() calls, tho the gains
in usability over high latency connections is huge. in most cases, programs
will just terminate when encountering these errors.
libdraw was attempting to bind '#i' and '#m' to /dev when it could not find
/dev/mouse or /dev/draw. a library shouldnt be that clever and do namespace
manipulations on behalf of the caller. so instead, we setup the graphics
environment in screenrc on boot time.
it is possible to have fonts belong to different or no display, so the
check for defaultsubfont has to be against font->display, not the global
display variable.
remove unused freeup() routine.
handle strdup() error in allocsubfont() and realloc() error in buildfont().
stringwidth() and string() sometimes failed spuriously due
to the wrong assumption that cachechars() will only fail
when a different subfont is needed. in fact, cachechars()
can fail for other reasons like when it resizes the fontcache
(or fails todo so).
theres also the case when loadchar() is unable to translate
a character and returns 0. this case needs to be differentiated
from such temporary conditions like fontcache resize or subfont
load to stop the retry loop in string() and stringwidth().
now cachechars() returns -1 to indicate that it cannot
proceed and we test this in string() and stringwidth()
to skip over untranslatable characters to make progress
instead of retrying.
cachechars() used to skip over characters on its own when
loadchar() could not find the character or a PJW replacement.
this resulted in wrong width calculation. now we just return
and handle the case inside _string and _stringwidth.
fix subfont leak in stringwidth()
remove annoying prints in stringwidth()
newwindow() used to mount the new window directly on /dev, resulting
in the old window and the new one being mounted over each other.
we now try to unmount the old window from /dev first, mount new
window to /mnt/wsys (replacing the old) and then bind /mnt/wsys
before /dev.
if theres no /mnt/wsys, just mount window directly before /dev.
the changeset r541ead66e8af:
"libdraw: make ebread() return buffer immidiately if available"
makes mouse sluggish when the program cant keep up as mouse
events queue up. this more or less restores the original
behaviour but only for mouse events.
fix the default note handler for event programs. only handle non system
notes or notes in the slave processes. for interrupt in the main process,
just call exits() which will do the cleanup and restore window label
properly.
this makes completely overriding the note handler in gping and
stats uneccesary.
Sigrid
Ori Bernstein
cinap_lenrek
BurnZeZ
glenda
mischief
cinap_lenrek