prove that man-db and tar works(which used to segfault). hope builtin argp
could be updated soon. i will report if i met another NULL pointer case.
thanks for your work! :)
Bruno Haible 于2019年1月6日周日 上午12:17写道：
> He X wrote:
> > > The msgid argument is a null-terminated string.
> >
> > problem is that msgid is a empty pointer, not a pointer to a
> > NULL-terminated string.
> >
> > full backtrace:
> >
> > ```
> > #0 0x77fab65d in strcmp (l=0x0, r=0x77eff7df "Packaged by
> > %s\n") at src/string/strcmp.c:5
> > #1 0x77f51351 in __mo_lookup (p=0x77efa000, size=55838,
> s=0x0)
> > at src/locale/__mo_lookup.c:25
> > #2 0x77f51e14 in dcngettext (domainname=0x77ffe320 "tar",
> > msgid1=0x0, msgid2=0x0, n=1, category=5) at src/locale/dcngettext.c:211
> > #3 0x77f52204 in dgettext (domainname=0x0, msgid=0x0) at
> > src/locale/dcngettext.c:271
> > #4 0x5558a63c in argp_args_usage (argp=argp@entry
> =0x7fffe740,
> > state=state@entry=0x7fffe8f0, levels=levels@entry=0x7fffe690,
> > advance=advance@entry=1, stream=stream@entry=0x555c5e20) at
> > argp-help.c:1415
> > #5 0x5558bcdd in _help (argp=0x7fffe740,
> > state=state@entry=0x7fffe8f0,
> > stream=0x77ffb2a0 , flags=flags@entry=634,
> > name=0x7fffed94 "tar") at argp-help.c:1640
> > #6 0x5558ca08 in argp_state_help (state=state@entry
> =0x7fffe8f0,
> > stream=, flags=flags@entry=634) at argp-help.c:1741
> > #7 0x5558d088 in argp_default_parser (key=,
> > arg=, state=0x7fffe8f0) at argp-parse.c:96
> > #8 0x5558df89 in group_parse (arg=, key=63,
> > state=0x7fffe8f0, group=0x555c40b0) at argp-parse.c:234
> > #9 parser_parse_opt (val=, opt=50331711,
> > parser=0x7fffe880) at argp-parse.c:749
> > #10 parser_parse_next (arg_ebadkey=,
> > parser=0x7fffe880) at argp-parse.c:860
> > #11 argp_parse (argp=, argc=2, argv=,
> > flags=, end_index=0x7fffe9f0, input=0x555c3500
> > )
> > at argp-parse.c:928
> > #12 0xd3b7 in decode_options (argv=0x7fffffffeb58, argc=2) at
> > tar.c:2312
> > #13 main (argc=, argv=) at tar.c:2698
> > ```
>
> Thank you! With this stack trace, I'm fixing the issue as follows:
>
>
> 2019-01-05 Bruno Haible
>
> argp: Don't pass an invalid argument to dgettext().
> Reported by He X .
> * lib/argp.h (struct argp): Clarify that the args_doc field may be
> NULL.
> * lib/argp-help.c (argp_args_usage): Don't pass a NULL args_doc to
> dgettext().
>
> diff --git a/lib/argp.h b/lib/argp.h
> index 317ac03..7aba887 100644
> --- a/lib/argp.h
> +++ b/lib/argp.h
> @@ -69,6 +69,9 @@ typedef int error_t;
> extern "C" {
> #endif
>
> +/* Glibc documentation:
> + https://www.gnu.org/software/libc/manual/html_node/Argp.html */
> +
> /* A description of a particular option. A pointer to an array of
> these is passed in the OPTIONS field of an argp structure. Each option
> entry can correspond to one long option and/or one short option; more
> @@ -236,9 +239,9 @@ struct argp
> ARGP_KEY_ definitions below. */
>argp_parser_t parser;
>
> - /* A string describing what other arguments are wanted by this
> program. It
> - is only used by argp_usage to print the "Usage:" message. If it
> - contains newlines, the strings separated by them are considered
> + /* If non-NULL, a string describing what other arguments are wanted by
> this
> + program. It is only used by argp_usage to print the "Usage:"
> message.
> + If it contains newlines, the strings separated by them are considered
> alternative usage patterns, and printed on separate lines (lines
> after
> the first are prefix by " or: " instead of "Usage:"). */
>const char *args_doc;
> diff --git a/lib/argp-help.c b/lib/argp-help.c
> index e5375a0..e5e97ec 100644
> --- a/lib/argp-help.c
> +++ b/lib/argp-help.c
> @@ -1412,8 +1412,10 @@ argp_args_usage (const struct argp *argp, const
> struct argp_state *state,
>char *our_level = *levels;
>int multiple = 0;
>const struct argp_child *child = argp->children;
> - const char *tdoc = dgettext (argp->argp_domain, argp->args_doc), *nl =
> 0;
> + const char *tdoc =
> +argp->args_doc ? dgettext (argp->argp_domain, argp->args_doc) : NULL;
>const char *fdoc = filter_doc (tdoc, ARGP_KEY_HELP_ARGS_DOC, argp,
> state);
> + const char *nl = NULL;
>
>
