On Tue, Mar 30, 2021 at 08:37:22AM +0200, Juraj Lutter wrote:
> Hi,
>
> very similar behavior is observed in editors/poke, on recent 13.0-STABLE
> (stable/13-85ad493677a2):
>
> (lldb) bt
> * thread #1, name = 'poke', stop reason = signal SIGSEGV: invalid address
> (fault address: 0x0)
> * frame #0: 0x
> frame #1: 0x0008009ed30a
> libncursesw.so.9`delay_output_sp(sp=0x, ms=) at
> lib_tputs.c:104:6
The SCREEN pointer sp is null here: which could occur if there was
no matching terminal description. I noticed that libtextstyle doesn't
give up on that error, but just proceeds along as though other functions
which would return the terminal capabilities will somehow return valid
data when the terminal database isn't initialized.
> frame #2: 0x0008009edb81 libncursesw.so.9`tputs_sp [inlined]
> delay_output(ms=) at lib_tputs.c:116:12
> frame #3: 0x0008009edb72 libncursesw.so.9`tputs_sp(sp=,
> string="", affcnt=1, outc=) at lib_tputs.c:422
> frame #4: 0x0008009edcfb
> libncursesw.so.9`tputs(string="4f0fdc740005bebaf92e5a2e", affcnt=1,
> outc=(libtextstyle.so.0`out_char at term-ostream.oo.c:1198)) at
> lib_tputs.c:444:12
well yes... The caller is supposed to provide outch via tputs,
which isn't a parameter of delay_output (but delay_output needs it).
ncurses saves/restores that pointer in the SCREEN structure --
if it's initialized -- otherwise in a static structure. It's made
a little more complicated since some paths use stdout and others
use ncurses' buffering via outch (which may be unrelated to stdout).
That pointer-juggling dates back to late 2009 -- but of course other
changes have occurred since then.
So... the question I have is what is $TERM in this case,
and where is the related terminal description (in terminfo or termcap).
Knowing that would help me see whether the problem is faulty initialization
from libtextstyle (i.e., the SCREEN pointer is null, making the path via
the static structure), or some ifdef-combination in ncurses that I've
neglected (i.e., a flaw in the pointer juggling).
> frame #5: 0x000800424bb0
> libtextstyle.so.0`out_hyperlink_change(stream=0x000800e3d000,
> new_hyperlink=0x0008018bd600, async_safe=false) at
> term-ostream.oo.c:1586:7
> frame #6: 0x00080042579c
> libtextstyle.so.0`out_attr_change(stream=0x000800e3d000,
> new_attr=attributes_t @ 0x7fffe608) at term-ostream.oo.c:1737:11
> frame #7: 0x000800424f3b
> libtextstyle.so.0`output_buffer(stream=0x000800e3d000,
> goal_attr=attributes_t @ 0x7fffe690) at term-ostream.oo.c:1906:11
> frame #8: 0x0008004223b2
> libtextstyle.so.0`term_ostream__write_mem(stream=0x000800e3d000,
> data=0x00207a94, len=123) at term-ostream.oo.c:2037:11
> frame #9: 0x000800422ed5
> libtextstyle.so.0`term_ostream_write_mem(first_arg=0x000800e3d000,
> data=0x00207a94, len=123) at term-ostream.c:2721:3
> frame #10: 0x000800427e3f
> libtextstyle.so.0`term_styled_ostream__write_mem(stream=0x000800e3a000,
> data=0x00207a94, len=123) at term-styled-ostream.oo.c:95:3
> frame #11: 0x000800420535
> libtextstyle.so.0`ostream_write_mem(first_arg=0x000800e3a000,
> data=0x00207a94, len=123) at ostream.c:138:3
> frame #12: 0x0008004204ec
> libtextstyle.so.0`ostream_write_str(stream=0x000800e3a000,
> string=".\nThis is free software: you are free to change and redistribute
> it.\nThere is NO WARRANTY, to the extent permitted by law.\n") at
> ostream.oo.c:35:3
> frame #13: 0x00210add poke`pk_puts(str=".\nThis is free software:
> you are free to change and redistribute it.\nThere is NO WARRANTY, to the
> extent permitted by law.\n") at pk-term.c:257:3
>
>
> Iny my case, there is a NULL pointer dereference in delay_output_ch(), where
> my_outch is NULL:
>
> frame #0: 0x0008009ed2da
> libncursesw.so.9`delay_output_sp(sp=0x, ms=4) at
> lib_tputs.c:103:22
>100 register int nullcount;
>101
>102 nullcount = (ms * _nc_baudrate(ospeed)) / (BAUDBYTE * 1000);
> -> 103 for (_nc_nulls_sent += nullcount; nullcount > 0; nullcount--)
>104 my_outch(NCURSES_SP_ARGx PC);
>105 if (my_outch == NCURSES_SP_NAME(_nc_outch))
>106 NCURSES_SP_NAME(_nc_flush) (NCURSES_SP_ARG);
>
> Application is using term_styled_ostream_create() that does not initialize
> default_attr.
>
> > On 30 Mar 2021, at 01:31, Thomas Dickey wrote:
> >
> > On Mon, Mar 29, 2021 at 12:12:55PM -0700, Henric Jungheim wrote:
> >>
> >> I ran into a bit of an odd problem when building the
> >> sysutils/grub2-bhyve port on 13.0-RC3 (on x64). The bison command
> >> dumps core when the output is going to a console. Redirecting the
> >> build output to a file avoids the problem. I'm not sure if this is
> >> an ncurses issue, a port issue (and
