Ralf Wildenhues <[EMAIL PROTECTED]> writes:
> +verbs. On the other hand, commands after @[EMAIL PROTECTED] should be
> preceded
> +by @samp{;} unless preceded by a newline.
That's not strict enough, I'm afraid. The POSIX rule is that you
cannot use semicolons inside { } at all, in a sed script. Nor can you
use addresses like 1 or $ or /x/ inside { }; nor can you use !; and
there are some other limits.
Automake uses '{' within sed commands, so it should be swept for these
problems, too. I'll follow up on bug-automake.
I have added documentation for this in the Autoconf manual, as
described below. I also swept Autoconf for instances of this problem
and fixed all the ones that I found.
Here's the patch I installed.
2006-01-05 Paul Eggert <[EMAIL PROTECTED]>
Fix Posix-conformance bugs re use of { command in sed scripts,
and improve the sed-related documentation a bit.
* doc/autoconf.texi (Installation Directory Variables): Use
our own style advice re 's,a,b,' versus 's|a|b|'. Use "Sed"
rather than "sed" when talking about Sed in general.
(Particular Programs): Likewise.
(Coding Style): y is like s with respect to / and ,.
(Limitations of Usual Tools): Document the weird restrictions
that Posix has about { }. Use better quoting.
* lib/autoconf/status.m4 (_AC_OUTPUT_FILES_PREPARE, _AC_OUTPUT_HEADER):
Rewrite to conform to Posix rules about { } in sed scripts.
* lib/m4sugar/m4sh.m4 (AS_DIRNAME_SED, AS_BASENAME_SED): Likewise.
* tests/foreign.at (Libtool): Likewise.
* tests/semantics.at (AC_CHECK_PROG & AC_CHECK_PROGS):
Use our own style advice re 's,a,b,' versus 's|a|b|'.
Index: doc/autoconf.texi
===================================================================
RCS file: /cvsroot/autoconf/autoconf/doc/autoconf.texi,v
retrieving revision 1.939
diff -p -u -r1.939 autoconf.texi
--- doc/autoconf.texi 4 Jan 2006 22:28:37 -0000 1.939
+++ doc/autoconf.texi 5 Jan 2006 21:42:53 -0000
@@ -2458,8 +2458,8 @@ Makefile snippet similar to:
@example
@group
edit = sed \
- -e 's|@@datadir[@@]|$(pkgdatadir)|g' \
- -e 's|@@prefix[@@]|$(prefix)|g'
+ -e 's,@@datadir[@@],$(pkgdatadir),g' \
+ -e 's,@@prefix[@@],$(prefix),g'
@end group
@group
@@ -2484,7 +2484,7 @@ Some details are noteworthy:
@table @samp
@item @@datadir[@@]
The brackets prevent @command{configure} from replacing
[EMAIL PROTECTED]@@datadir@@} in the sed expression itself.
[EMAIL PROTECTED]@@datadir@@} in the Sed expression itself.
Brackets are preferable to a backslash here, since
Posix says @samp{\@@} is not portable.
@@ -2493,7 +2493,7 @@ Don't use @samp{@@pkgdatadir@@}! Use th
instead.
@item ,
-Don't use @samp{/} in the sed expression(s) since most likely the
+Don't use @samp{/} in the Sed expression(s) since most likely the
variables you use, such as @samp{$(pkgdatadir)}, will contain
some.
@@ -3509,7 +3509,7 @@ is found, and otherwise to @samp{:} (do
@defmac AC_PROG_SED
@acindex{PROG_SED}
@ovindex SED
-Set output variable @code{SED} to a @code{sed} on @env{PATH} that
+Set output variable @code{SED} to a Sed implementation on @env{PATH} that
truncates as few characters as possible. If @sc{gnu} Sed is found,
use that instead.
@end defmac
@@ -9619,9 +9619,9 @@ etc. If you add portability issues to t
better than hacking Autoconf @code{:-)}.
When using @command{sed}, don't use @option{-e} except for indenting
-purpose. With the @code{s} command, the preferred separator is @samp{/}
-unless @samp{/} itself is used in the command, in which case you should
-use @samp{,}.
+purposes. With the @code{s} and @code{y} commands, the preferred
+separator is @samp{/} unless @samp{/} itself might appear in the pattern
+or replacement, in which case you should use @samp{,}.
@xref{Macro Definitions}, for details on how to define a macro. If a
macro doesn't use @code{AC_REQUIRE} and it is expected to never be the
@@ -11397,7 +11397,7 @@ shift, but in addition it is not portabl
RISC/OS} 4.52 refuses to do it.
Don't use @samp{shift 2} etc.; it was not in the 7th Edition Bourne shell,
-and it is also absent in many pre-POSIX shells.
+and it is also absent in many pre-Posix shells.
@item @command{source}
@@ -12373,6 +12373,12 @@ but Posix says that this use of a semico
should use semicolon only with simple scripts that do not use these
verbs.
+Commands inside @{ @} brackets are further restricted. Posix says that
+they cannot be preceded by addresses, @samp{!}, or @samp{;}, and that
+each command must be followed immediately by a newline, without any
+intervening blanks or semicolons. The closing bracket must be alone on
+a line, other than white space preceding or following it.
+
Contrary to yet another urban legend, you may portably use @samp{&} in
the replacement part of the @code{s} command to mean ``what was
matched''. All descendants of Unix version 7 @command{sed}
@@ -12393,6 +12399,10 @@ $ @kbd{echo "foo" | sed -n '/bar/ !p'}
foo
@end example
+Posix also says that you should not combine @samp{!} and @samp{;}. If
+you use @samp{!}, it is best to put it on a command that is delimited by
+newlines rather than @samp{;}.
+
Also note that Posix requires that the @samp{b}, @samp{t}, @samp{r}, and
@samp{w} commands be followed by exactly one space before their argument.
On the other hand, no white space is allowed between @samp{:} and the
@@ -12443,20 +12453,21 @@ kept
deleted
@end example
-Why? When processing 1, a matches, therefore sets the t flag, b jumps to
-d, and the output is produced. When processing line 2, the t flag is
-still set (this is the bug). Line a fails to match, but @command{sed}
-is not supposed to clear the t flag when a substitution fails. Line b
-sees that the flag is set, therefore it clears it, and jumps to d, hence
-you get @samp{delete me} instead of @samp{deleted}. When processing 3, t
-is clear, a matches, so the flag is set, hence b clears the flags and
-jumps. Finally, since the flag is clear, 4 is processed properly.
+Why? When processing line 1, (a) matches, therefore sets the @samp{t}
+flag, (b)b jumps to (d), and the output is produced. When processing
+line 2, the @samp{t} flag is still set (this is the bug). Command (a)
+fails to match, but @command{sed} is not supposed to clear the @samp{t}
+flag when a substitution fails. Command (b) sees that the flag is set,
+therefore it clears it, and jumps to (d), hence you get @samp{delete me}
+instead of @samp{deleted}. When processing line (3), @samp{t} is clear,
+(a) matches, so the flag is set, hence (b) clears the flags and jumps.
+Finally, since the flag is clear, line 4 is processed properly.
There are two things one should remember about @samp{t} in @command{sed}.
Firstly, always remember that @samp{t} jumps if @emph{some} substitution
succeeded, not only the immediately preceding substitution. Therefore,
-always use a fake @samp{t clear; :clear} to reset the t flag where
-needed.
+always use a fake @samp{t clear} followed by a @samp{:clear} on the next
+line, to reset the @samp{t} flag where needed.
Secondly, you cannot rely on @command{sed} to clear the flag at each new
cycle.
Index: lib/autoconf/status.m4
===================================================================
RCS file: /cvsroot/autoconf/autoconf/lib/autoconf/status.m4,v
retrieving revision 1.81
diff -p -u -r1.81 status.m4
--- lib/autoconf/status.m4 5 Jan 2006 15:17:47 -0000 1.81
+++ lib/autoconf/status.m4 5 Jan 2006 21:42:53 -0000
@@ -1,7 +1,7 @@
# This file is part of Autoconf. -*- Autoconf -*-
# Parameterizing and creating config.status.
# Copyright (C) 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
-# 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+# 2002, 2003, 2004, 2005, 2006 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
@@ -363,7 +363,8 @@ m4_define([_AC_SED_CMD_NUM], m4_eval(_AC
m4_define([_AC_SED_FRAG],
m4_defn([_AC_SED_FRAG])dnl
[/^[ [EMAIL PROTECTED]@[ ]*$/{ r $]_AC_Var[
-d; }
+d
+}
])dnl
])dnl
# Remaining file output variables are in a fragment that also has non-file
@@ -461,12 +462,12 @@ m4_popdef([_AC_SED_FRAG])dnl
# (actually we leave an empty line to preserve line numbers).
if test "x$srcdir" = x.; then
ac_vpsub=['/^[ ]*VPATH[ ]*=/{
-s/:*\$(srcdir):*/:/;
-s/:*\${srcdir}:*/:/;
-s/:[EMAIL PROTECTED]@:*/:/;
-s/^\([^=]*=[ ]*\):*/\1/;
-s/:*$//;
-s/^[^=]*=[ ]*$//;
+s/:*\$(srcdir):*/:/
+s/:*\${srcdir}:*/:/
+s/:[EMAIL PROTECTED]@:*/:/
+s/^\([^=]*=[ ]*\):*/\1/
+s/:*$//
+s/^[^=]*=[ ]*$//
}']
fi
@@ -643,9 +644,10 @@ do
dnl Quote, for the `[ ]' and `define'.
echo [' # First, check the format of the line:
cat >"$tmp/defines.sed" <<CEOF
-/^[ ]*#[ ]*undef[ ][ ]*$ac_word_regexp[ ]*$/!{
-/^[ ]*#[ ]*define[ ][ ]*$ac_word_regexp[( ]/!b
-}'] >>$CONFIG_STATUS
+/^[ ]*#[ ]*undef[ ][ ]*$ac_word_regexp[ ]*$/b def
+/^[ ]*#[ ]*define[ ][ ]*$ac_word_regexp[( ]/b def
+b
+:def'] >>$CONFIG_STATUS
sed ${ac_max_sed_lines}q conftest.defines >>$CONFIG_STATUS
echo 'CEOF
sed -f "$tmp/defines.sed"' "$ac_in >$ac_out" >>$CONFIG_STATUS
Index: lib/m4sugar/m4sh.m4
===================================================================
RCS file: /cvsroot/autoconf/autoconf/lib/m4sugar/m4sh.m4,v
retrieving revision 1.152
diff -p -u -r1.152 m4sh.m4
--- lib/m4sugar/m4sh.m4 2 Dec 2005 19:22:49 -0000 1.152
+++ lib/m4sugar/m4sh.m4 5 Jan 2006 21:42:53 -0000
@@ -2,7 +2,7 @@
# M4 sugar for common shell constructs.
# Requires GNU M4 and M4sugar.
#
-# Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005 Free Software
+# Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software
# Foundation, Inc.
#
# This program is free software; you can redistribute it and/or modify
@@ -639,11 +639,23 @@ $as_expr X[]$1 : 'X\(.*[[^/]]\)//*[[^/][
m4_defun([AS_DIRNAME_SED],
[echo X[]$1 |
- sed ['/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{ s//\1/; q; }
- /^X\(\/\/\)[^/].*/{ s//\1/; q; }
- /^X\(\/\/\)$/{ s//\1/; q; }
- /^X\(\/\).*/{ s//\1/; q; }
- s/.*/./; q']])
+ sed ['/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
+ s//\1/
+ q
+ }
+ /^X\(\/\/\)[^/].*/{
+ s//\1/
+ q
+ }
+ /^X\(\/\/\)$/{
+ s//\1/
+ q
+ }
+ /^X\(\/\).*/{
+ s//\1/
+ q
+ }
+ s/.*/./; q']])
m4_defun([AS_DIRNAME],
[(dirname $1) 2>/dev/null ||
@@ -665,10 +677,19 @@ $as_expr X/[]$1 : '.*/\([[^/][^/]*]\)/*$
m4_defun([AS_BASENAME_SED],
[echo X/[]$1 |
- sed ['/^.*\/\([^/][^/]*\)\/*$/{ s//\1/; q; }
- /^X\/\(\/\/\)$/{ s//\1/; q; }
- /^X\/\(\/\).*/{ s//\1/; q; }
- s/.*/./; q']])
+ sed ['/^.*\/\([^/][^/]*\)\/*$/{
+ s//\1/
+ q
+ }
+ /^X\/\(\/\/\)$/{
+ s//\1/
+ q
+ }
+ /^X\/\(\/\).*/{
+ s//\1/
+ q
+ }
+ s/.*/./; q']])
m4_defun([AS_BASENAME],
[AS_REQUIRE([_$0_PREPARE])dnl
Index: tests/foreign.at
===================================================================
RCS file: /cvsroot/autoconf/autoconf/tests/foreign.at,v
retrieving revision 1.23
diff -p -u -r1.23 foreign.at
--- tests/foreign.at 14 May 2005 07:00:40 -0000 1.23
+++ tests/foreign.at 5 Jan 2006 21:42:53 -0000
@@ -2,7 +2,7 @@
AT_BANNER([Compatibility with other tools.])
-# Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005 Free Software
+# Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software
# Foundation, Inc.
#
# This program is free software; you can redistribute it and/or modify
@@ -33,7 +33,11 @@ AT_CHECK([libtoolize --version || exit 7
# CVS Autoconf probably does not work with too old Libtools.
AT_CHECK([[
case `libtoolize --version |
- sed -n '/^.* \([0-9][0-9.a-z]*\)$/{s//\1/;p;q;}'` in
+ sed -n '/^.* \([0-9][0-9.a-z]*\)$/{
+ s//\1/
+ p
+ q
+ }'` in
0.* ) exit 77;;
1.[0123]* ) exit 77;;
esac]],
Index: tests/semantics.at
===================================================================
RCS file: /cvsroot/autoconf/autoconf/tests/semantics.at,v
retrieving revision 1.52
diff -p -u -r1.52 semantics.at
--- tests/semantics.at 27 Sep 2005 16:08:12 -0000 1.52
+++ tests/semantics.at 5 Jan 2006 21:42:53 -0000
@@ -2,7 +2,8 @@
AT_BANNER([Semantics.])
-# Copyright (C) 2000, 2001, 2002, 2004, 2005 Free Software Foundation, Inc.
+# Copyright (C) 2000, 2001, 2002, 2004, 2005, 2006 Free Software
+# Foundation, Inc.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
@@ -420,7 +421,7 @@ AT_DATA([configure.ac],
[[AC_INIT
pwd=`pwd`
p="1${PATH_SEPARATOR}2${PATH_SEPARATOR}3${PATH_SEPARATOR}4${PATH_SEPARATOR}5${PATH_SEPARATOR}6"
-path=`echo $p | sed -e 's|\([[0-9]]\)|'"$pwd"'/path/\1|g'`
+path=`echo $p | sed -e 's,\([[0-9]]\),'"$pwd"'/path/\1,g'`
fail=false
AC_CHECK_PROG(TOOL1, tool, found, not-found, $path)
@@ -507,7 +508,7 @@ AT_DATA([configure.ac],
[[AC_INIT
pwd=`pwd`
p="1${PATH_SEPARATOR}2${PATH_SEPARATOR}3${PATH_SEPARATOR}4${PATH_SEPARATOR}5${PATH_SEPARATOR}6"
-path=`echo $p | sed -e 's|\([[0-9]]\)|'"$pwd"'/path/\1|g'`
+path=`echo $p | sed -e 's,\([[0-9]]\),'"$pwd"'/path/\1,g'`
fail=false
AC_PATH_PROG(TOOL1, tool, not-found, $path)
