Pull useless-if-before-free from gnulib, and update.

* bootstrap (gnulib_tool): Add useless-if-before-free to
the list of modules.
* build-aux/useless-if-before-free: Update from gnulib.
* gnulib/lib/vasnprintf.c: Work around a bug in HPUX 10.20.
* gnulib/m4/vasnprintf.m4: Likewise.

ChangeLog

@@ -1,6 +1,15 @@
+Wed Feb 13 22:51:27 CET 2008 Jim Meyering  <meyering@redhat.com>
+
+	Pull useless-if-before-free from gnulib, and update.
+	* bootstrap (gnulib_tool): Add useless-if-before-free to
+	the list of modules.
+	* build-aux/useless-if-before-free: Update from gnulib.
+	* gnulib/lib/vasnprintf.c: Work around a bug in HPUX 10.20.
+	* gnulib/m4/vasnprintf.m4: Likewise.
+
 Tue Feb 12 9:44:22 EST 2008 Daniel P. Berrange <berrange@redhat.com>
 
-	* .x-sc_trailing_blank: ignore NEWS / ChangeLog file 
+	* .x-sc_trailing_blank: ignore NEWS / ChangeLog file
 
 Mon Feb 11 17:05:53 CET 2008 Daniel Veillard <veillard@redhat.com>
 

bootstrap

@@ -78,6 +78,7 @@ $gnulib_tool			\
   --import physmem getaddrinfo  \
     sys_stat vasprintf strndup  \
     strsep poll gettext getpass \
+    useless-if-before-free      \
     vc-list-files
 
 rm -f				\

build-aux/useless-if-before-free

@@ -1,24 +1,43 @@
 #!/usr/bin/perl -T
 # Detect instances of "if (p) free (p);".
-# Likewise for "if (p != NULL) free (p);".
+# Likewise for "if (p != NULL) free (p);".  And with braces.
 
-my $VERSION = '2008-02-04 22:25'; # UTC
+my $VERSION = '2008-02-11 08:08'; # UTC
 # The definition above must lie within the first 8 lines in order
 # for the Emacs time-stamp write hook (at end) to update it.
 # If you change this file with Emacs, please let the write hook
 # do its job.  Otherwise, update this string manually.
 
-# Exit status is like grep: 0 for no match. 1 for any number.
+# Copyright (C) 2008 Free Software Foundation, Inc.
-# Note: giving line numbers isn't practical, since I've reset the
+
-# input record separator.
+# 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 <http://www.gnu.org/licenses/>.
+
+# Written by Jim Meyering
+
 use strict;
 use warnings;
 use Getopt::Long;
 
 (my $ME = $0) =~ s|.*/||;
 
-my $debug = 0;
+# use File::Coda; # http://meyering.net/code/Coda/
-my $verbose = 0;
+END {
+  defined fileno STDOUT or return;
+  close STDOUT and return;
+  warn "$ME: failed to close standard output: $!\n";
+  $? ||= 1;
+}
 
 sub usage ($)
 {
@@ -33,18 +52,32 @@ sub usage ($)
       print $STREAM <<EOF;
 Usage: $ME [OPTIONS] FILE...
 
+Detect any instance in FILE of a useless "if" test before a free call, e.g.,
+"if (p) free (p);".  Any such test may be safely removed without affecting
+the semantics of the C code in FILE.  Use --name=FOO --name=BAR to also
+detect free-like functions named FOO and BAR.
+
 OPTIONS:
 
+   --list       print only the name of each matching FILE (\0-terminated)
    --name=N     add name N to the list of `free'-like functions to detect;
                   may be repeated
 
    --help       display this help and exit
    --version    output version information and exit
-   --verbose    generate verbose output
+
+Exit status:
+
+  0   no match
+  1   one or more matches
+  2   an error
 
 EXAMPLE:
 
-    git ls-files -z |xargs -0 $ME
+For example, this command prints all removable "if" tests before "free"
+and "kfree" calls in the linux kernel sources:
+
+    git ls-files -z |xargs -0 $ME --name=kfree
 
 EOF
     }
@@ -52,32 +85,40 @@ EOF
 }
 
 {
+  sub EXIT_MATCH {0}
+  sub EXIT_NO_MATCH {1}
+  sub EXIT_ERROR {2}
+  my $err = EXIT_NO_MATCH;
+
+  my $list;
   my @name = qw(free);
   GetOptions
     (
-     debug => \$debug,
-     verbose => \$verbose,
      help => sub { usage 0 },
      version => sub { print "$ME version $VERSION\n"; exit },
+     list => \$list,
      'name=s@' => \@name,
     ) or usage 1;
 
   # Make sure we have the right number of non-option arguments.
   # Always tell the user why we fail.
   @ARGV < 1
-    and (warn "$ME: missing FILE argument\n"), usage 1;
+    and (warn "$ME: missing FILE argument\n"), usage EXIT_ERROR;
 
   my $or = join '|', @name;
   my $regexp = qr/(?:$or)/;
 
   # Set the input record separator.
+  # Note: this makes it impractical to print line numbers.
   $/ = '"';
 
   my $found_match = 0;
+ FILE:
   foreach my $file (@ARGV)
     {
       open FH, '<', $file
-        or die "$ME: can't open `$file' for reading: $!\n";
+        or (warn "$ME: can't open `$file' for reading: $!\n"),
+          $err = EXIT_ERROR, next;
       while (defined (my $line = <FH>))
         {
           if ($line =~
@@ -85,27 +126,40 @@ EOF
                (?:   \s*$regexp\s*\(\s*\2\s*\)|
                 \s*\{\s*$regexp\s*\(\s*\2\s*\)\s*;\s*\}))/sx)
             {
-              print "$file: $1\n";
               $found_match = 1;
+              $list
+                and (print "$file\0"), next FILE;
+              print "$file: $1\n";
             }
         }
+    }
+  continue
+    {
       close FH;
     }
-  exit !$found_match;
+
+  $found_match && $err == EXIT_NO_MATCH
+    and $err = EXIT_MATCH;
+
+  exit $err;
 }
 
 my $foo = <<'EOF';
 # The above is to *find* them.
 # This adjusts them, removing the unnecessary "if (p)" part.
 
-# FIXME: do something like this as an option.
+# FIXME: do something like this as an option (doesn't do braces):
-git ls-files -z --exclude=$ME |xargs -0 \
+git ls-files -z |xargs -0 \
-perl -0x3b -pi -e 's/\bif\s*\(\s*(\S+?)(?:\s*!=\s*NULL)?\s*\)\s+((?:sexpr_)?free\s*\(\s*\1\s*\))/$2/s'
+perl -0x3b -pi -e 's/\bif\s*\(\s*(\S+?)(?:\s*!=\s*NULL)?\s*\)\s+(k?free\s*\(\s*\1\s*\))/$2/s'
+
+useless-if-before-free -l $(lid -knone free) | xargs -0 \
+  perl -0x3b -pi -e \
+   's/\bif\s*\(\s*(\S+?)(?:\s*!=\s*NULL)?\s*\)\s+(free\s*\(\s*\1\s*\))/$2/s'
+
+Be careful that the result of the above transformation is valid.
+If the matched string is followed by "else", then obviously, it won't be.
 
 When modifying files, refuse to process anything other than a regular file.
-
-# Or this one-liner to detect them:
-git ls-files -z |xargs -0 perl -00 -ne '/\b(if\s*\(\s*(\S+?)(?:\s*!=\s*NULL)?\s*\)(?:\s*(?:sexpr_)?free\s*\(\s*\2\s*\)|\s*\{\s*(?:sexpr_)?free\s*\(\s*\2\s*\)\s*;\s*\}))/sx and print "$1\n"'
 EOF
 
 ## Local Variables:

gnulib/lib/Makefile.am

@@ -9,7 +9,7 @@
 # the same distribution terms as the rest of that program.
 #
 # Generated by gnulib-tool.
-# Reproduce by: gnulib-tool --import --dir=. --lib=libgnu --source-base=gnulib/lib --m4-base=gnulib/m4 --doc-base=doc --aux-dir=build-aux --with-tests --lgpl=2 --libtool --macro-prefix=gl getaddrinfo getpass gettext physmem poll strndup strsep sys_stat vasprintf vc-list-files
+# Reproduce by: gnulib-tool --import --dir=. --lib=libgnu --source-base=gnulib/lib --m4-base=gnulib/m4 --doc-base=doc --aux-dir=build-aux --with-tests --lgpl=2 --libtool --macro-prefix=gl getaddrinfo getpass gettext physmem poll strndup strsep sys_stat useless-if-before-free vasprintf vc-list-files
 
 AUTOMAKE_OPTIONS = 1.5 gnits
 
@@ -701,6 +701,13 @@ EXTRA_DIST += unistd.in.h
 
 ## end   gnulib module unistd
 
+## begin gnulib module useless-if-before-free
+
+
+EXTRA_DIST += $(top_srcdir)/build-aux/useless-if-before-free
+
+## end   gnulib module useless-if-before-free
+
 ## begin gnulib module vasnprintf
 
 

gnulib/lib/vasnprintf.c

@@ -3566,7 +3566,7 @@ VASNPRINTF (DCHAR_T *resultbuf, size_t *lengthp,
 	      {
 		arg_type type = a.arg[dp->arg_index].type;
 		int flags = dp->flags;
-#if !USE_SNPRINTF || !DCHAR_IS_TCHAR || ENABLE_UNISTDIO || NEED_PRINTF_FLAG_ZERO || NEED_PRINTF_UNBOUNDED_PRECISION
+#if !USE_SNPRINTF || !DCHAR_IS_TCHAR || ENABLE_UNISTDIO || NEED_PRINTF_FLAG_LEFTADJUST || NEED_PRINTF_FLAG_ZERO || NEED_PRINTF_UNBOUNDED_PRECISION
 		int has_width;
 		size_t width;
 #endif
@@ -3579,7 +3579,9 @@ VASNPRINTF (DCHAR_T *resultbuf, size_t *lengthp,
 #else
 #		define prec_ourselves 0
 #endif
-#if !DCHAR_IS_TCHAR || ENABLE_UNISTDIO || NEED_PRINTF_FLAG_ZERO || NEED_PRINTF_UNBOUNDED_PRECISION
+#if NEED_PRINTF_FLAG_LEFTADJUST
+#		define pad_ourselves 1
+#elif !DCHAR_IS_TCHAR || ENABLE_UNISTDIO || NEED_PRINTF_FLAG_ZERO || NEED_PRINTF_UNBOUNDED_PRECISION
 		int pad_ourselves;
 #else
 #		define pad_ourselves 0
@@ -3593,7 +3595,7 @@ VASNPRINTF (DCHAR_T *resultbuf, size_t *lengthp,
 		TCHAR_T *tmp;
 #endif
 
-#if !USE_SNPRINTF || !DCHAR_IS_TCHAR || ENABLE_UNISTDIO || NEED_PRINTF_FLAG_ZERO || NEED_PRINTF_UNBOUNDED_PRECISION
+#if !USE_SNPRINTF || !DCHAR_IS_TCHAR || ENABLE_UNISTDIO || NEED_PRINTF_FLAG_LEFTADJUST || NEED_PRINTF_FLAG_ZERO || NEED_PRINTF_UNBOUNDED_PRECISION
 		has_width = 0;
 		width = 0;
 		if (dp->width_start != dp->width_end)
@@ -3883,7 +3885,7 @@ VASNPRINTF (DCHAR_T *resultbuf, size_t *lengthp,
 #endif
 
 		/* Decide whether to perform the padding ourselves.  */
-#if !DCHAR_IS_TCHAR || ENABLE_UNISTDIO || NEED_PRINTF_FLAG_ZERO || NEED_PRINTF_UNBOUNDED_PRECISION
+#if !NEED_PRINTF_FLAG_LEFTADJUST && (!DCHAR_IS_TCHAR || ENABLE_UNISTDIO || NEED_PRINTF_FLAG_ZERO || NEED_PRINTF_UNBOUNDED_PRECISION)
 		switch (dp->conversion)
 		  {
 # if !DCHAR_IS_TCHAR || ENABLE_UNISTDIO
@@ -4008,7 +4010,7 @@ VASNPRINTF (DCHAR_T *resultbuf, size_t *lengthp,
 #endif
 		  *fbp = dp->conversion;
 #if USE_SNPRINTF
-# if !(__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 3))
+# if !(__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 3) || ((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__))
 		fbp[1] = '%';
 		fbp[2] = 'n';
 		fbp[3] = '\0';
@@ -4021,6 +4023,21 @@ VASNPRINTF (DCHAR_T *resultbuf, size_t *lengthp,
 		   in format strings in writable memory may crash the program
 		   (if compiled with _FORTIFY_SOURCE=2), so we should avoid it
 		   in this situation.  */
+		/* On native Win32 systems (such as mingw), we can avoid using
+		   %n because:
+		     - Although the gl_SNPRINTF_TRUNCATION_C99 test fails,
+		       snprintf does not write more than the specified number
+		       of bytes. (snprintf (buf, 3, "%d %d", 4567, 89) writes
+		       '4', '5', '6' into buf, not '4', '5', '\0'.)
+		     - Although the gl_SNPRINTF_RETVAL_C99 test fails, snprintf
+		       allows us to recognize the case of an insufficient
+		       buffer size: it returns -1 in this case.
+		   On native Win32 systems (such as mingw) where the OS is
+		   Windows Vista, the use of %n in format strings by default
+		   crashes the program. See
+		     <http://gcc.gnu.org/ml/gcc/2007-06/msg00122.html> and
+		     <http://msdn2.microsoft.com/en-us/library/ms175782(VS.80).aspx>
+		   So we should avoid %n in this situation.  */
 		fbp[1] = '\0';
 # endif
 #else
@@ -4494,7 +4511,7 @@ VASNPRINTF (DCHAR_T *resultbuf, size_t *lengthp,
 		    /* Here count <= allocated - length.  */
 
 		    /* Perform padding.  */
-#if !DCHAR_IS_TCHAR || ENABLE_UNISTDIO || NEED_PRINTF_FLAG_ZERO || NEED_PRINTF_UNBOUNDED_PRECISION
+#if !DCHAR_IS_TCHAR || ENABLE_UNISTDIO || NEED_PRINTF_FLAG_LEFTADJUST || NEED_PRINTF_FLAG_ZERO || NEED_PRINTF_UNBOUNDED_PRECISION
 		    if (pad_ourselves && has_width)
 		      {
 			size_t w;
@@ -4535,15 +4552,14 @@ VASNPRINTF (DCHAR_T *resultbuf, size_t *lengthp,
 # endif
 			      DCHAR_T *p = rp + count;
 			      DCHAR_T *end = p + pad;
-# if NEED_PRINTF_FLAG_ZERO
 			      DCHAR_T *pad_ptr;
-#  if !DCHAR_IS_TCHAR
+# if !DCHAR_IS_TCHAR
 			      if (dp->conversion == 'c'
 				  || dp->conversion == 's')
 				/* No zero-padding for string directives.  */
 				pad_ptr = NULL;
 			      else
-#  endif
+# endif
 				{
 				  pad_ptr = (*rp == '-' ? rp + 1 : rp);
 				  /* No zero-padding of "inf" and "nan".  */
@@ -4551,7 +4567,6 @@ VASNPRINTF (DCHAR_T *resultbuf, size_t *lengthp,
 				      || (*pad_ptr >= 'a' && *pad_ptr <= 'z'))
 				    pad_ptr = NULL;
 				}
-# endif
 			      /* The generated string now extends from rp to p,
 				 with the zero padding insertion point being at
 				 pad_ptr.  */
@@ -4564,7 +4579,6 @@ VASNPRINTF (DCHAR_T *resultbuf, size_t *lengthp,
 				  for (; pad > 0; pad--)
 				    *p++ = ' ';
 				}
-# if NEED_PRINTF_FLAG_ZERO
 			      else if ((flags & FLAG_ZERO) && pad_ptr != NULL)
 				{
 				  /* Pad with zeroes.  */
@@ -4575,7 +4589,6 @@ VASNPRINTF (DCHAR_T *resultbuf, size_t *lengthp,
 				  for (; pad > 0; pad--)
 				    *p++ = '0';
 				}
-# endif
 			      else
 				{
 				  /* Pad with spaces on the left.  */

gnulib/m4/gnulib-cache.m4

@@ -15,11 +15,11 @@
 
 
 # Specification in the form of a command-line invocation:
-#   gnulib-tool --import --dir=. --lib=libgnu --source-base=gnulib/lib --m4-base=gnulib/m4 --doc-base=doc --aux-dir=build-aux --with-tests --lgpl=2 --libtool --macro-prefix=gl getaddrinfo getpass gettext physmem poll strndup strsep sys_stat vasprintf vc-list-files
+#   gnulib-tool --import --dir=. --lib=libgnu --source-base=gnulib/lib --m4-base=gnulib/m4 --doc-base=doc --aux-dir=build-aux --with-tests --lgpl=2 --libtool --macro-prefix=gl getaddrinfo getpass gettext physmem poll strndup strsep sys_stat useless-if-before-free vasprintf vc-list-files
 
 # Specification in the form of a few gnulib-tool.m4 macro invocations:
 gl_LOCAL_DIR([])
-gl_MODULES([getaddrinfo getpass gettext physmem poll strndup strsep sys_stat vasprintf vc-list-files])
+gl_MODULES([getaddrinfo getpass gettext physmem poll strndup strsep sys_stat useless-if-before-free vasprintf vc-list-files])
 gl_AVOID([])
 gl_SOURCE_BASE([gnulib/lib])
 gl_M4_BASE([gnulib/m4])

gnulib/m4/gnulib-comp.m4

@@ -225,6 +225,7 @@ AC_DEFUN([gltests_LIBSOURCES], [
 AC_DEFUN([gl_FILE_LIST], [
   build-aux/config.rpath
   build-aux/link-warning.h
+  build-aux/useless-if-before-free
   build-aux/vc-list-files
   lib/alloca.in.h
   lib/asnprintf.c

gnulib/m4/vasnprintf.m4

@@ -1,5 +1,5 @@
-# vasnprintf.m4 serial 23
+# vasnprintf.m4 serial 24
-dnl Copyright (C) 2002-2004, 2006-2007 Free Software Foundation, Inc.
+dnl Copyright (C) 2002-2004, 2006-2008 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
@@ -166,6 +166,21 @@ AC_DEFUN([gl_PREREQ_VASNPRINTF_FLAG_GROUPING],
   esac
 ])
 
+# Extra prerequisites of lib/vasnprintf.c for supporting the '-' flag.
+AC_DEFUN([gl_PREREQ_VASNPRINTF_FLAG_LEFTADJUST],
+[
+  AC_REQUIRE([gl_PRINTF_FLAG_LEFTADJUST])
+  case "$gl_cv_func_printf_flag_leftadjust" in
+    *yes)
+      ;;
+    *)
+      AC_DEFINE([NEED_PRINTF_FLAG_LEFTADJUST], 1,
+        [Define if the vasnprintf implementation needs special code for the
+         '-' flag.])
+      ;;
+  esac
+])
+
 # Extra prerequisites of lib/vasnprintf.c for supporting the 0 flag.
 AC_DEFUN([gl_PREREQ_VASNPRINTF_FLAG_ZERO],
 [
@@ -234,6 +249,7 @@ AC_DEFUN([gl_PREREQ_VASNPRINTF_WITH_EXTRAS],
   gl_PREREQ_VASNPRINTF_DIRECTIVE_A
   gl_PREREQ_VASNPRINTF_DIRECTIVE_F
   gl_PREREQ_VASNPRINTF_FLAG_GROUPING
+  gl_PREREQ_VASNPRINTF_FLAG_LEFTADJUST
   gl_PREREQ_VASNPRINTF_FLAG_ZERO
   gl_PREREQ_VASNPRINTF_PRECISION
   gl_PREREQ_VASNPRINTF_ENOMEM