Re: [PATCH] argp: argp.doc prints incorrectly when it starts with "\v" [BZ #19038]

[Girish Joshi <girish946 at gmail dot com>]

Could anyone please review this patch?
Thanks.

Girish Joshi
girishjoshi.io

On Mon, Nov 25, 2019 at 11:38 PM Girish Joshi <girish946@gmail.com> wrote:
>
> Thanks Joseph for the review.
> Here is a patch with the required changes.
> Please let me know if more changes are needed in it.
>
> argp/argp-help.c: added validation for leading \v in the doc string.
> argp/tst-argp3.c: added test case when the doc string contains leading \v.
> argp/Makefile: added tst-argp3 to tests
>
> Overview:
> argp.doc prints incorrectly when it starts with '\v'.
> In argp-help.c in the function  variable  is being
> initialized only once, which causes the whole documentation to be printed if
> there is a leading '\v' in the doc string.
>
> Implementation:
> It needs to be initialized for every child in the doc and it needs to be printed
> only in two cases.
> 1. There are no children and the doc does not starts with '\v'.
> 2. Argument  to the function  is false and the
> complete doc needs to be printed.
> ---
>  argp/Makefile    |  2 +-
>  argp/argp-help.c | 10 +++++--
>  argp/tst-argp3.c | 68 ++++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 77 insertions(+), 3 deletions(-)
>  create mode 100644 argp/tst-argp3.c
>
> diff --git a/argp/Makefile b/argp/Makefile
> index c97e4c307c..8206da8cd8 100644
> --- a/argp/Makefile
> +++ b/argp/Makefile
> @@ -27,7 +27,7 @@ routines    = $(addprefix argp-, ba fmtstream
> fs-xinl help parse pv \
>                       pvh xinl eexst)
>
>  tests        = argp-test tst-argp1 bug-argp1 tst-argp2 bug-argp2 \
> -          tst-ldbl-argp
> +          tst-ldbl-argp tst-argp3
>
>  CFLAGS-argp-help.c += $(uses-callbacks) -fexceptions
>  CFLAGS-argp-parse.c += $(uses-callbacks)
> diff --git a/argp/argp-help.c b/argp/argp-help.c
> index 85f5792bfe..68422127d2 100644
> --- a/argp/argp-help.c
> +++ b/argp/argp-help.c
> @@ -1465,10 +1465,11 @@ argp_doc (const struct argp *argp, const
> struct argp_state *state,
>    size_t inp_text_limit = 0;
>    const char *doc = dgettext (argp->argp_domain, argp->doc);
>    const struct argp_child *child = argp->children;
> +  char *vt = 0;
>
>    if (doc)
>      {
> -      char *vt = strchr (doc, '\v');
> +      vt = strchr (doc, '\v');
>        inp_text = post ? (vt ? vt + 1 : 0) : doc;
>        inp_text_limit = (!post && vt) ? (vt - doc) : 0;
>      }
> @@ -1499,7 +1500,12 @@ argp_doc (const struct argp *argp, const struct
> argp_state *state,
>        if (text == inp_text && inp_text_limit)
>      __argp_fmtstream_write (stream, inp_text, inp_text_limit);
>        else
> -    __argp_fmtstream_puts (stream, text);
> +      {
> +        if ((!vt && !child) || (text == inp_text && !first_only))
> +        {
> +          __argp_fmtstream_puts (stream, text);
> +        }
> +      }
>
>        if (__argp_fmtstream_point (stream) > __argp_fmtstream_lmargin (stream))
>      __argp_fmtstream_putc (stream, '\n');
> diff --git a/argp/tst-argp3.c b/argp/tst-argp3.c
> new file mode 100644
> index 0000000000..997072ba7d
> --- /dev/null
> +++ b/argp/tst-argp3.c
> @@ -0,0 +1,68 @@
> +/* Test for argparse with leading '\v' in the doc string.
> +  Copyright (C) 2019 Free Software Foundation, Inc.
> +
> +  This program is free software: you can redistribute it and/or modify
> +  it under the terms of the GNU General Public License as published by
> +  the Free Software Foundation; either version 3 of the License, or
> +  (at your option) any later version.
> +
> +  This program is distributed in the hope that it will be useful,
> +  but WITHOUT ANY WARRANTY; without even the implied warranty of
> +  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> +  GNU General Public License for more details.
> +
> +  You should have received a copy of the GNU General Public License
> +  along with this program.  If not, see <https://www.gnu.org/licenses/>.*/
> +
> +
> +#include<stdlib.h>
> +#include<argp.h>
> +
> +#include <support/capture_subprocess.h>
> +#include <support/check.h>
> +
> +
> +static char expected_success[] = "Usage: arp [OPTION...]\n\
> +\n\
> +  -?, --help                 Give this help list\n\
> +      --usage                Give a short usage message\n\
> +\n\
> +this is post_doc\n\
> +";
> +char *argv[3] = { (char *) "arp", NULL, NULL };
> +
> +static void
> +do_test_call (void)
> +{
> +  static char doc[] = "\vthis is post_doc";
> +  static struct argp argp = {NULL, NULL, NULL, doc};
> +
> +  argp_parse (&argp, 2, argv, 0, 0, NULL);
> +}
> +
> +static int
> +do_one_test (const char *expected)
> +{
> +  struct support_capture_subprocess result;
> +  result = support_capture_subprocess ((void *) &do_test_call, NULL);
> +
> +  TEST_COMPARE_STRING (result.out.buffer, expected);
> +
> +  return 0;
> +}
> +
> +
> +static int
> +do_test (void)
> +{
> +  const char *argument = "--help";
> +  argv[1] = (char *)argument;
> +  // success condition
> +  do_one_test (expected_success);
> +  return 0;
> +}
> +
> +/* This file references do_test above and contains the definition of
> +   the main function.  */
> +#include <support/test-driver.c>
> +
> --
> 2.21.0
>
>
> Girish Joshi
> girishjoshi.io