Re: segv with :_correct or :_correct:_approximate

Re: segv with :_correct or :_correct:_approximate

[Sven Wischnowsky]

fmarx@new-york.crosswinds.net wrote:

> With `completer' set to either `completer=_complete:_correct' or
> 			       `completer=_complete:_correct:_approximate'
> in the new Completion model, I'm seeing a segv.
> `completer=_complete' appears o.k.
> 
> To reproduce it: attempt completion on any non-existent file, with
> correction enabled.

Phew, not really a completion problem. Wayne, this happens when
freehistdata() calls removehashnode() with a histent with
he->text==NULL. I'm not sure if this shows that there is a bug
somewhere else, so I won't build a patch for it.

(All this with HIST_NO_FUNCTIONS, it tries to remove a function
definition from the history at that time.)

Bye
 Sven


--
Sven Wischnowsky                         wischnow@informatik.hu-berlin.de

Re: segv with :_correct or :_correct:_approximate

[Wayne Davison]

On Wed, 2 Jun 1999, Sven Wischnowsky wrote:
> Wayne, this happens when freehistdata() calls removehashnode()
> with a histent with he->text==NULL.

It's actually slightly worse than that, it would have tried to free
the static "curline" structure if it had successfully free'd the
structure's data.

> (All this with HIST_NO_FUNCTIONS, it tries to remove a function
> definition from the history at that time.)

Yes, this is the meat of the problem -- remhist() is being called to
remove a history line when the function definition did not come from
the history -- ouch.  (Before my history changes, the code would have
successfully lost the last history line from the internal history as
a side-effect of completing the current history line.)

So, I've got a simple fix for this particular problem (I'll post a
patch in a moment), but I think in the long run we need to redesign
the "remhist()" stuff.  In addition to the problems of when the
remhist() function should be called and when it shouldn't, the new
SHARE_HISTORY code writes out a history line to the history file
right after you type it, and it cannot easily remove the line post
facto if the code later decides to call remhist().

I'm thinking that it would be best if we could identify the lines
that shouldn't be added to the history file before we save them,
rather than removing them afterwards.  I see two possible ways to do
this.  Either come up with a way to identify the non-saved commands
earlier, or move the history-saving later.

One solution might be to implement a pattern-matching system (an
array of regular expressions?) that would identify the lines that
should not be remembered.  The existing history-removing options
(including HIST_IGNORE_SPACE) would be implemented using this
system.  This would allow the current history-saving code to avoid
ever adding these lines to the history in the first place, and would
not be affected by things like the defining of functions in
completion scripts.  (This would also allow someone to easily add a
pattern to ignore short commands -- e.g.  /^..?$/).

..wayne..

segv with :_correct or :_correct:_approximate

[F. G. Marx]

With `completer' set to either `completer=_complete:_correct' or
			       `completer=_complete:_correct:_approximate'
in the new Completion model, I'm seeing a segv.
`completer=_complete' appears o.k.

To reproduce it: attempt completion on any non-existent file, with
correction enabled.

gdb bt follows my compinit.dump.

compinit.dump
-------------
#files: 92
_comps=(
'-' '_precommand'
'-brace-parameter-' '_brace_parameter'
'-command-' '_command_names'
'-condition-' '_condition'
'-default-' '_default'
'-equal-' '_equal'
'-math-' '_math'
'-parameter-' '_parameter'
'-redirect-' '_redirect'
'-subscript-' '_subscript'
.
.
.
'xdvi' '_dvi'
'xfig' '_xfig'
'xping' '_hosts'
'zcat' '_gunzip'
'zle' '_zle'
'zmodload' '_zmodload'
'zmore' '_uncompress'
)

_patcomps=(
'zf* _zftp'
'*/X11/* _x_options'
)

zle -C _complete_list-choices list-choices _main_complete
zle -C _complete_menu-complete menu-complete _main_complete
zle -C _correct_filename complete-word _correct_filename
zle -C _correct_word complete-word _correct_word
zle -C _most_recent_file complete-word _most_recent_file
bindkey '^D' _complete_list-choices
bindkey '^I' _complete_menu-complete
bindkey '^XC' _correct_filename
bindkey '^Xc' _correct_word
bindkey '^Xm' _most_recent_file
bindkey '^[[[A' _complete_list-choices

autoload _a2ps _aliases _approximate _arrays _autoload
autoload _bg_jobs _bindkey _brace_parameter _builtin _cd
autoload _closequotes _command _command_names _compalso _complete
autoload _compress _condition _configure _correct _correct_filename
autoload _correct_word _dd _default _dirs _disable
autoload _dvi _echotc _enable _equal _expand
autoload _fc _files _find _functions _gunzip
autoload _gzip _hash _hosts _jobs _kill
autoload _limits _list _long_options _main_complete _make
autoload _man _match _math _menu _mh
autoload _most_recent_file _multi_parts _normal _oldlist _options
autoload _parameter _parameters _path_files _pdf _precommand
autoload _ps _rcs _redirect _rlogin _sched
autoload _sep_parts _set _set_options _setopt _source
autoload _stat _strip _stty _subscript _tar
autoload _tar_archive _tex _tilde _trap _uncompress
autoload _unhash _unset_options _unsetopt _vars _vars_eq
autoload _wait _which _x_options _xfig _zftp
autoload _zle _zmodload


gdb bt
------

[~shells/zsh-3.1.5-pws-20/Src 0] gdb zshg
gdb> r -l
Starting program: /src/source/shells/zsh-3.1.5-pws-20/Src/zshg -l

[~ 0] cd ~zsh/Completion
~zsh/Completion ~ ~shells/zsh-3.1.5-pws-20/Src
[~zsh/Completion 0] ls Core/_usx
Program received signal SIGSEGV, Segmentation fault.
0x400cfa03 in free () from /lib/libc.so.6
gdb> bt
#0  0x400cfa03 in free () from /lib/libc.so.6
#1  0x807ddc2 in zfree (p=0x80b65c0, sz=44) at mem.c:1280
#2  0x806c39c in freehistnode (nodeptr=0x80b65c0) at hashtable.c:1351
#3  0x806e306 in remhist () at hist.c:989
#4  0x80612b3 in execfuncdef (cmd=0x812a058) at exec.c:2703
#5  0x805f38b in execcmd (cmd=0x812a058, input=0, output=0, how=2, last1=2) at exec.c:1881
#6  0x805cc4e in execpline2 (pline=0x812a048, how=2, input=0, output=0, last1=0) at exec.c:1014
#7  0x805c440 in execpline (l=0x812a034, how=2, last1=0) at exec.c:858
#8  0x805c098 in execlist (list=0x812a024, dont_change_job=1, exiting=0) at exec.c:731
#9  0x80615cb in execautofn (cmd=0x8126238) at exec.c:2777
#10 0x805f38b in execcmd (cmd=0x8126238, input=0, output=0, how=2, last1=2) at exec.c:1881
#11 0x805cc4e in execpline2 (pline=0x8126228, how=2, input=0, output=0, last1=0) at exec.c:1014
#12 0x805c440 in execpline (l=0x8126214, how=2, last1=0) at exec.c:858
#13 0x805c098 in execlist (list=0x8126204, dont_change_job=1, exiting=0) at exec.c:731
#14 0x8061a5a in runshfunc (list=0x80d38a8, wrap=0x0, name=0x80d38c0 "_approximate") at exec.c:2922
#15 0x401bdb91 in comp_wrapper (list=0x80d38a8, w=0x0, name=0x80d38c0 "_approximate") at compctl.c:2368
#16 0x80619cf in runshfunc (list=0x80d38a8, wrap=0x401bfe88, name=0x80d38c0 "_approximate") at exec.c:2908
#17 0x80617fa in doshfunc (name=0x80d38c0 "_approximate", list=0x80d38a8, doshargs=0x8133d50, flags=128, noreturnval=0)
    at exec.c:2840
#18 0x80613f2 in execshfunc (cmd=0x8125e4c, shf=0x80d3828) at exec.c:2738
#19 0x805f50e in execcmd (cmd=0x8125e4c, input=0, output=0, how=2, last1=2) at exec.c:1917
#20 0x805cc4e in execpline2 (pline=0x8133d40, how=2, input=0, output=0, last1=0) at exec.c:1014
#21 0x805c440 in execpline (l=0x8133d2c, how=2, last1=0) at exec.c:858
#22 0x805c0b2 in execlist (list=0x8133d1c, dont_change_job=1, exiting=0) at exec.c:737
#23 0x80615cb in execautofn (cmd=0x8132ab0) at exec.c:2777
#24 0x805f38b in execcmd (cmd=0x8132ab0, input=0, output=0, how=2, last1=2) at exec.c:1881
#25 0x805cc4e in execpline2 (pline=0x8132aa0, how=2, input=0, output=0, last1=0) at exec.c:1014
#26 0x805c440 in execpline (l=0x8132a8c, how=2, last1=0) at exec.c:858
#27 0x805c098 in execlist (list=0x8132a7c, dont_change_job=1, exiting=0) at exec.c:731
#28 0x8061a5a in runshfunc (list=0x80d4368, wrap=0x0, name=0x80d4380 "_correct") at exec.c:2922
#29 0x401bdb91 in comp_wrapper (list=0x80d4368, w=0x0, name=0x80d4380 "_correct") at compctl.c:2368
#30 0x80619cf in runshfunc (list=0x80d4368, wrap=0x401bfe88, name=0x80d4380 "_correct") at exec.c:2908
#31 0x80617fa in doshfunc (name=0x80d4380 "_correct", list=0x80d4368, doshargs=0x8132980, flags=128, noreturnval=0) at exec.c:2840
#32 0x80613f2 in execshfunc (cmd=0x8132960, shf=0x80d42e8) at exec.c:2738
#33 0x805f50e in execcmd (cmd=0x8132960, input=0, output=0, how=2, last1=2) at exec.c:1917
#34 0x805cc4e in execpline2 (pline=0x8132950, how=2, input=0, output=0, last1=0) at exec.c:1014
#35 0x805c440 in execpline (l=0x813293c, how=2, last1=0) at exec.c:858
#36 0x805c0b2 in execlist (list=0x813292c, dont_change_job=1, exiting=0) at exec.c:737
#37 0x807a0e8 in execfor (cmd=0x81324f0) at loop.c:104
#38 0x805f38b in execcmd (cmd=0x81324f0, input=0, output=0, how=2, last1=2) at exec.c:1881
#39 0x805cc4e in execpline2 (pline=0x81324e0, how=2, input=0, output=0, last1=0) at exec.c:1014
#40 0x805c440 in execpline (l=0x81324cc, how=2, last1=0) at exec.c:858
#41 0x805c098 in execlist (list=0x81324bc, dont_change_job=1, exiting=0) at exec.c:731
#42 0x80615cb in execautofn (cmd=0x81089e4) at exec.c:2777
#43 0x805f38b in execcmd (cmd=0x81089e4, input=0, output=0, how=2, last1=2) at exec.c:1881
#44 0x805cc4e in execpline2 (pline=0x81089d4, how=2, input=0, output=0, last1=0) at exec.c:1014
#45 0x805c440 in execpline (l=0x81089c0, how=2, last1=0) at exec.c:858
#46 0x805c098 in execlist (list=0x81089b0, dont_change_job=1, exiting=0) at exec.c:731
#47 0x8061a5a in runshfunc (list=0x80d53e0, wrap=0x0, name=0x80edf38 "_main_complete") at exec.c:2922
#48 0x401bdb91 in comp_wrapper (list=0x80d53e0, w=0x0, name=0x80edf38 "_main_complete") at compctl.c:2368
#49 0x80619cf in runshfunc (list=0x80d53e0, wrap=0x401bfe88, name=0x80edf38 "_main_complete") at exec.c:2908
#50 0x80617fa in doshfunc (name=0x80edf38 "_main_complete", list=0x80d53e0, doshargs=0x0, flags=0, noreturnval=1) at exec.c:2840
#51 0x4019be67 in callcompfunc (s=0x80bd7a4 "Core/_usx", fn=0x80edf38 "_main_complete") at zle_tricky.c:4507
#52 0x4019c625 in makecomplist (s=0x80bd7a4 "Core/_usx", incmd=0, lst=0) at zle_tricky.c:4659
#53 0x4019b03c in docompletion (s=0x80b98e0 "Core/_usx", lst=0, incmd=0) at zle_tricky.c:4223
#54 0x40192a86 in docomplete (lst=0) at zle_tricky.c:1005
#55 0x40191247 in menucomplete () at zle_tricky.c:406
#56 0x40191111 in completecall () at zle_tricky.c:376
#57 0x401874d0 in execzlefunc (func=0x80edf50) at zle_main.c:624
#58 0x40186f48 in zleread (lp=0x80b9e70 "[%~ 0] ", rp=0x0, flags=3) at zle_main.c:543
#59 0x8072984 in inputline () at input.c:263
#60 0x807286d in ingetc () at input.c:208
#61 0x806c65b in hgetc () at hist.c:223
#62 0x80773ad in gettok () at lex.c:526
#63 0x8076d39 in yylex () at lex.c:289
#64 0x8086c8c in parse_event () at parse.c:99
#65 0x80708ff in loop (toplevel=1, justonce=0) at init.c:100
#66 0x80506b9 in main (argc=2, argv=0xbffff7d4) at ./main.c:77
gdb> q
The program is running.  Exit anyway? (y or n) y