On Monday 05 of October 2015 00:45:50 Pavel Raiskup wrote:
> > should we test the size of the string first ? i've written such raw shell
> > string parsing functions before, and once you hit a certain size (like 1k+
> > iirc), forking out to sed is way faster, especially when running in
> > multibyte
> > locales (like UTF8) which most people are doing nowadays.
> > -mike
>
> Well, that optimization would require (fast) strlen()-like construct.
> Anyway, the vast majority of calls to func_quote () function will have
> short ARG, and its complexity is still "just" linear. We could optimize
> later if that was a real issue.
>
> I would like to propose solution based on Eric's one, without using of
> '${VAR%.}' and '${VAR#.}' constructs -- sounds like this could be even
> more portable while it keeps almost the same speed (if we can use += its
> even faster).
>
> I have yet a another patch trying to minimize option-parser overhead
> (that is focused on the POV of Richard, but that needs to be cleaned up a
> bit, I'll post hopefully tomorrow).
>
> Any comment is welcome!
Re-attached (fixes for 'make syntax-check' and fixed one comment).
Pavel
>From f6935309a07b2a4797ff5612bff00ced4842c3e5 Mon Sep 17 00:00:00 2001
From: Pavel Raiskup <prais...@redhat.com>
Date: Sun, 4 Oct 2015 21:55:03 +0200
Subject: [PATCH] libtool: mitigate the $sed_quote_subst slowdown
References:
http://lists.gnu.org/archive/html/libtool/2015-03/msg00005.html
http://lists.gnu.org/archive/html/libtool/2015-02/msg00000.html
https://debbugs.gnu.org/cgi/bugreport.cgi?bug=20006
* gl/build-aux/funclib.sh (func_quote): New function that can be
used as substition for '$SED $sed_quote_subst' call.
* build-aux/ltmain.in (func_emit_wrapper): Use func_quote instead
of '$SED $sed_quote_subst'.
(func_mode_link): Likewise.
* NEWS: Document.
* bootstrap: Sync with funclib.sh.
---
NEWS | 3 +++
bootstrap | 49 +++++++++++++++++++++++++++++++++++++++++++++++--
build-aux/ltmain.in | 10 ++++++----
gl/build-aux/funclib.sh | 49 +++++++++++++++++++++++++++++++++++++++++++++++--
4 files changed, 103 insertions(+), 8 deletions(-)
diff --git a/NEWS b/NEWS
index a3c5b12..7c23d03 100644
--- a/NEWS
+++ b/NEWS
@@ -17,6 +17,9 @@ NEWS - list of user-visible changes between releases of GNU Libtool
- Fix significant slowdown of libtoolize for certain projects (regression
introduced in 2.4.3 release) caused by infinite m4 macro recursion.
+ - Mitigate the slowdown of libtool script (introduced in v2.4.3) caused by
+ increased number of calls to '$SED $sed_quote_subst' (bug#20006).
+
* Noteworthy changes in release 2.4.6 (2015-02-15) [stable]
** New features:
diff --git a/bootstrap b/bootstrap
index c179f51..c2f6545 100755
--- a/bootstrap
+++ b/bootstrap
@@ -230,7 +230,7 @@ vc_ignore=
# Source required external libraries:
# Set a version string for this script.
-scriptversion=2015-01-20.17; # UTC
+scriptversion=2015-10-04.22; # UTC
# General shell script boiler plate, and helper functions.
# Written by Gary V. Vaughan, 2004
@@ -1257,6 +1257,50 @@ func_relative_path ()
}
+# func_quote ARG
+# --------------
+# Aesthetically quote one ARG, store the result into $func_quote_result. Note
+# that we keep attention to performance here (so far O(N) complexity as long as
+# func_append is O(1)).
+func_quote ()
+{
+ $debug_cmd
+
+ func_quote_result=$1
+ func_quote_old_IFS=$IFS
+
+ case $func_quote_result in
+ *[\\\`\"\$]*)
+ for _G_char in '\' '`' '"' '$'
+ do
+ # STATE($1) PREV($2) SEPARATOR($3)
+ set start "" ""
+ func_quote_result=dummy"$_G_char$func_quote_result$_G_char"dummy
+ IFS=$_G_char
+ for _G_part in $func_quote_result
+ do
+ case $1 in
+ quote)
+ func_append func_quote_result "$3$2"
+ set quote "$_G_part" "\\$_G_char"
+ ;;
+ start)
+ set first "" ""
+ func_quote_result=
+ ;;
+ first)
+ set quote "$_G_part" ""
+ ;;
+ esac
+ done
+ IFS=$func_quote_old_IFS
+ done
+ ;;
+ *) ;;
+ esac
+}
+
+
# func_quote_for_eval ARG...
# --------------------------
# Aesthetically quote ARGs to be evaled later.
@@ -1275,7 +1319,8 @@ func_quote_for_eval ()
while test 0 -lt $#; do
case $1 in
*[\\\`\"\$]*)
- _G_unquoted_arg=`printf '%s\n' "$1" |$SED "$sed_quote_subst"` ;;
+ func_quote "$1"
+ _G_unquoted_arg=$func_quote_result ;;
*)
_G_unquoted_arg=$1 ;;
esac
diff --git a/build-aux/ltmain.in b/build-aux/ltmain.in
index 0c40da0..24acefd 100644
--- a/build-aux/ltmain.in
+++ b/build-aux/ltmain.in
@@ -3346,7 +3346,8 @@ else
if test \"\$libtool_execute_magic\" != \"$magic\"; then
file=\"\$0\""
- qECHO=`$ECHO "$ECHO" | $SED "$sed_quote_subst"`
+ func_quote "$ECHO"
+ qECHO=$func_quote_result
$ECHO "\
# A function that is used when there is no print builtin or printf.
@@ -8596,8 +8597,8 @@ EOF
relink_command="$var=$func_quote_for_eval_result; export $var; $relink_command"
fi
done
- relink_command="(cd `pwd`; $relink_command)"
- relink_command=`$ECHO "$relink_command" | $SED "$sed_quote_subst"`
+ func_quote "(cd `pwd`; $relink_command)"
+ relink_command=$func_quote_result
fi
# Only actually do things if not in dry run mode.
@@ -8843,7 +8844,8 @@ EOF
done
# Quote the link command for shipping.
relink_command="(cd `pwd`; $SHELL \"$progpath\" $preserve_args --mode=relink $libtool_args @inst_prefix_dir@)"
- relink_command=`$ECHO "$relink_command" | $SED "$sed_quote_subst"`
+ func_quote "$relink_command"
+ relink_command=$func_quote_result
if test yes = "$hardcode_automatic"; then
relink_command=
fi
diff --git a/gl/build-aux/funclib.sh b/gl/build-aux/funclib.sh
index 39d972e..1a406cd 100644
--- a/gl/build-aux/funclib.sh
+++ b/gl/build-aux/funclib.sh
@@ -1,5 +1,5 @@
# Set a version string for this script.
-scriptversion=2015-01-20.17; # UTC
+scriptversion=2015-10-04.22; # UTC
# General shell script boiler plate, and helper functions.
# Written by Gary V. Vaughan, 2004
@@ -1026,6 +1026,50 @@ func_relative_path ()
}
+# func_quote ARG
+# --------------
+# Aesthetically quote one ARG, store the result into $func_quote_result. Note
+# that we keep attention to performance here (so far O(N) complexity as long as
+# func_append is O(1)).
+func_quote ()
+{
+ $debug_cmd
+
+ func_quote_result=$1
+ func_quote_old_IFS=$IFS
+
+ case $func_quote_result in
+ *[\\\`\"\$]*)
+ for _G_char in '\' '`' '"' '$'
+ do
+ # STATE($1) PREV($2) SEPARATOR($3)
+ set start "" ""
+ func_quote_result=dummy"$_G_char$func_quote_result$_G_char"dummy
+ IFS=$_G_char
+ for _G_part in $func_quote_result
+ do
+ case $1 in
+ quote)
+ func_append func_quote_result "$3$2"
+ set quote "$_G_part" "\\$_G_char"
+ ;;
+ start)
+ set first "" ""
+ func_quote_result=
+ ;;
+ first)
+ set quote "$_G_part" ""
+ ;;
+ esac
+ done
+ IFS=$func_quote_old_IFS
+ done
+ ;;
+ *) ;;
+ esac
+}
+
+
# func_quote_for_eval ARG...
# --------------------------
# Aesthetically quote ARGs to be evaled later.
@@ -1044,7 +1088,8 @@ func_quote_for_eval ()
while test 0 -lt $#; do
case $1 in
*[\\\`\"\$]*)
- _G_unquoted_arg=`printf '%s\n' "$1" |$SED "$sed_quote_subst"` ;;
+ func_quote "$1"
+ _G_unquoted_arg=$func_quote_result ;;
*)
_G_unquoted_arg=$1 ;;
esac
--
2.5.0
_______________________________________________
https://lists.gnu.org/mailman/listinfo/libtool
