[PATCH] Fix argp-help

[PATCH] Fix argp-help

[Jakub Jelinek]

Hi!

I have managed to write a testcase that reproduces the bug reported in
BZ#4101.  But when that is fixed, I see another crash.  argp_help
calls _help with state == NULL, this for ARGP_HELP_LONG calls
hol_help, also with state == NULL.
This can call:
  if (hhstate.suppressed_dup_arg && uparams.dup_args_note)
    {
      const char *tstr = dgettext (state == NULL ? NULL
                                   : state->root_argp->argp_domain, "\
Mandatory or optional arguments to long options are also mandatory or \
optional for any corresponding short options.");
      const char *fstr = filter_doc (tstr, ARGP_KEY_HELP_DUP_ARGS_NOTE,
                                     state ? state->root_argp : 0, state);
and as state is NULL, filter_doc is called with argp == NULL.
But filter_doc dereferences argp to check argp->argp_filter in the first
statement.

2007-03-15  Jakub Jelinek  <jakub@redhat.com>

	[BZ #4101]
	* argp/argp-help.c (hol_cluster_cmp): Fix comparisons used to find
	ancestors with the same depths.
	Patch by Niels Moeller <nisse@lysator.liu.se>.
	(filter_doc): Don't crash if argp is NULL.
	* argp/Makefile (tests): Add tst-argp2.
	* argp/tst-argp2.c: New test.

--- libc/argp/argp-help.c.jj	2006-05-10 08:28:06.000000000 +0200
+++ libc/argp/argp-help.c	2007-03-15 14:17:18.000000000 +0100
@@ -1,5 +1,6 @@
 /* Hierarchial argument parsing help output
-   Copyright (C) 1995-2003, 2004, 2005, 2006 Free Software Foundation, Inc.
+   Copyright (C) 1995-2003, 2004, 2005, 2006, 2007
+   Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Written by Miles Bader <miles@gnu.ai.mit.edu>.
 
@@ -672,9 +673,9 @@ hol_cluster_cmp (const struct hol_cluste
 {
   /* If one cluster is deeper than the other, use its ancestor at the same
      level, so that finding the common ancestor is straightforward.  */
-  while (cl1->depth < cl2->depth)
+  while (cl1->depth > cl2->depth)
     cl1 = cl1->parent;
-  while (cl2->depth < cl1->depth)
+  while (cl2->depth > cl1->depth)
     cl2 = cl2->parent;
 
   /* Now reduce both clusters to their ancestors at the point where both have
@@ -987,7 +988,7 @@ static const char *
 filter_doc (const char *doc, int key, const struct argp *argp,
 	    const struct argp_state *state)
 {
-  if (argp->help_filter)
+  if (argp && argp->help_filter)
     /* We must apply a user filter to this output.  */
     {
       void *input = __argp_input (argp, state);
--- libc/argp/Makefile.jj	2006-05-10 00:42:24.000000000 +0200
+++ libc/argp/Makefile	2007-03-15 14:19:32.000000000 +0100
@@ -1,4 +1,4 @@
-# Copyright (C) 1997, 2002, 2003, 2006 Free Software Foundation, Inc.
+# Copyright (C) 1997, 2002, 2003, 2006, 2007 Free Software Foundation, Inc.
 # This file is part of the GNU C Library.
 
 # The GNU C Library is free software; you can redistribute it and/or
@@ -26,7 +26,7 @@ distribute	= argp-fmtstream.h argp-namef
 routines	= $(addprefix argp-, ba fmtstream fs-xinl help parse pv \
 				     pvh xinl eexst)
 
-tests		= argp-test tst-argp1 bug-argp1
+tests		= argp-test tst-argp1 bug-argp1 tst-argp2
 
 CFLAGS-argp-help.c = $(uses-callbacks) -fexceptions
 CFLAGS-argp-parse.c = $(uses-callbacks)
--- libc/argp/tst-argp2.c.jj	2007-03-15 13:52:52.000000000 +0100
+++ libc/argp/tst-argp2.c	2007-03-15 14:06:27.000000000 +0100
@@ -0,0 +1,101 @@
+/* Copyright (C) 2007 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Jakub Jelinek <jakub@redhat.com>, 2007.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <argp.h>
+
+static const struct argp_option opt1[] =
+  {
+    { "opt1", '1', "NUMBER", 0, "Option 1" },
+    { NULL, 0, NULL, 0, NULL }
+  };
+
+static const struct argp_option opt2[] =
+  {
+    { "opt2", '2', "NUMBER", 0, "Option 2" },
+    { NULL, 0, NULL, 0, NULL }
+  };
+
+static const struct argp_option opt3[] =
+  {
+    { "opt3", '3', "NUMBER", 0, "Option 3" },
+    { NULL, 0, NULL, 0, NULL }
+  };
+
+static const struct argp_option opt4[] =
+  {
+    { "opt4", '4', "NUMBER", 0, "Option 4" },
+    { NULL, 0, NULL, 0, NULL }
+  };
+
+static const struct argp_option opt5[] =
+  {
+    { "opt5", '5', "NUMBER", 0, "Option 5" },
+    { NULL, 0, NULL, 0, NULL }
+  };
+
+static struct argp argp5 =
+  {
+    opt5, NULL, "args doc5", "doc5", NULL, NULL, NULL
+  };
+
+static struct argp argp4 =
+  {
+    opt4, NULL, "args doc4", "doc4", NULL, NULL, NULL
+  };
+
+static struct argp argp3 =
+  {
+    opt3, NULL, "args doc3", "doc3", NULL, NULL, NULL
+  };
+
+static struct argp_child children2[] =
+  {
+    { &argp4, 0, "child3", 3 },
+    { &argp5, 0, "child4", 4 },
+    { NULL, 0, NULL, 0 }
+  };
+
+static struct argp argp2 =
+  {
+    opt2, NULL, "args doc2", "doc2", children2, NULL, NULL
+  };
+
+static struct argp_child children1[] =
+  {
+    { &argp2, 0, "child1", 1 },
+    { &argp3, 0, "child2", 2 },
+    { NULL, 0, NULL, 0 }
+  };
+
+static struct argp argp1 =
+  {
+    opt1, NULL, "args doc1", "doc1", children1, NULL, NULL
+  };
+
+
+static int
+do_test (void)
+{
+  argp_help (&argp1, stdout, ARGP_HELP_LONG, "tst-argp2");
+  return 0;
+}
+
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"

	Jakub