mirror/autoconf
2
0
Fork 0
mirror of git://git.sv.gnu.org/autoconf synced 2024-12-09 02:10:22 +08:00
Code Issues Packages Projects Releases Wiki Activity

Optimize checking for identifiers.

Browse Source 
* lib/m4sugar/m4sh.m4 (AS_IDENTIFIER_IF, _AS_IDENTIFIER_IF): New
macros, more efficient than regex on m4_re_word.
* lib/autoconf/general.m4 (AC_SUBST, AC_DEFINE_TRACE_LITERAL):
Rewrite in terms of new macro.  As a side-effect, AC_DEFINE can
now use @&t@.
* configure: Regenerate.

Signed-off-by: Eric Blake <ebb9@byu.net>
This commit is contained in:
Eric Blake 2007-10-03 17:18:59 -06:00
parent 8b299b6d82
commit e76d30be25
4 changed files with 46 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
ChangeLog
View File

@ -1,5 +1,13 @@
2007-10-03 Eric Blake <ebb9@byu.net>
Optimize checking for identifiers.
* lib/m4sugar/m4sh.m4 (AS_IDENTIFIER_IF, _AS_IDENTIFIER_IF): New
macros, more efficient than regex on m4_re_word.
* lib/autoconf/general.m4 (AC_SUBST, AC_DEFINE_TRACE_LITERAL):
Rewrite in terms of new macro. As a side-effect, AC_DEFINE can
now use @&t@.
* configure: Regenerate.
Remove some XFAILs, and make AT_SETUP output line up.
* lib/autotest/general.m4 (AT_SETUP): Only expand description
once; thereafter, use its expansion, properly quoted.

16
configure vendored
View File

@ -373,10 +373,10 @@ fi
if test "x$CONFIG_SHELL" != x; then
for as_var in BASH_ENV ENV
do ($as_unset $as_var) >/dev/null 2>&1 && $as_unset $as_var
done
export CONFIG_SHELL
exec "$CONFIG_SHELL" "$as_myself" ${1+"$@"}
do ($as_unset $as_var) >/dev/null 2>&1 && $as_unset $as_var
done
export CONFIG_SHELL
exec "$CONFIG_SHELL" "$as_myself" ${1+"$@"}
fi
@ -561,10 +561,10 @@ else
as_test_x='
eval sh -c '\''
if test -d "$1"; then
test -d "$1/.";
test -d "$1/.";
else
case $1 in
-*)set "./$1";;
-*)set "./$1";;
esac;
case `ls -ld'$as_ls_L_option' "$1" 2>/dev/null` in
???[sx]*):;;*)false;;esac;fi
@ -3307,10 +3307,10 @@ else
as_test_x='
eval sh -c '\''
if test -d "$1"; then
test -d "$1/.";
test -d "$1/.";
else
case $1 in
-*)set "./$1";;
-*)set "./$1";;
esac;
case `ls -ld'$as_ls_L_option' "$1" 2>/dev/null` in
???[sx]*):;;*)false;;esac;fi

4
lib/autoconf/general.m4
View File

@ -1998,7 +1998,7 @@ AC_DEFUN([_AC_CACHE_CHECK_INT],
# Used by --trace to collect the list of AC_DEFINEd macros.
m4_define([AC_DEFINE_TRACE_LITERAL],
[m4_pattern_allow([^$1$])dnl
m4_bmatch([$1], ^m4_defn([m4_re_word])$, [],
AS_IDENTIFIER_IF([$1], [],
[m4_warn([syntax], [AC_DEFINE: not an identifier: $1])])dnl
])# AC_DEFINE_TRACE_LITERAL
@ -2060,7 +2060,7 @@ m4_define([AC_SUBST_TRACE])
# empty value, not an empty second argument.
#
m4_define([AC_SUBST],
[m4_bmatch(m4_bpatsubst([[$1]], [@&t@]), ^m4_defn([m4_re_word])$, [],
[AS_IDENTIFIER_IF([$1], [],
[AC_FATAL([$0: `$1' is not a valid shell variable name])])dnl
AC_SUBST_TRACE([$1])dnl
m4_pattern_allow([^$1$])dnl

28
lib/m4sugar/m4sh.m4
View File

@ -1226,6 +1226,34 @@ m4_popdef([AS_Prefix])dnl
])# AS_HELP_STRING
# AS_IDENTIFIER_IF(EXPRESSION, IF-IDENT, IF-NOT-IDENT)
# ----------------------------------------------------
# If EXPRESSION serves as an identifier (ie, after removal of @&t@, it
# matches the regex `^[a-zA-Z_][a-zA-Z_0-9]*$'), execute IF-IDENT,
# otherwise IF-NOT-IDENT.
#
# This is generally faster than the alternative:
# m4_bmatch(m4_bpatsubst([[$1]], [@&t@]), ^m4_defn([m4_re_word])$,
# [$2], [$3])
#
# Rather than expand m4_defn every time AS_IDENTIFIER_IF is expanded, we
# inline its expansion up front. Only use a regular expression if we
# detect a potential quadrigraph.
#
# First, check if the entire string matches m4_cr_symbol2. Only then do
# we worry if the first character also matches m4_cr_symbol1 (ie. does not
# match m4_cr_digit).
m4_define([AS_IDENTIFIER_IF],
[m4_if(m4_index([$1], [@]), [-1],
[_$0($@)],
[_$0(m4_bpatsubst([[$1]], [@&t@]), [$2], [$3])])])
m4_define([_AS_IDENTIFIER_IF],
[m4_if([$1], [], [$3],
m4_translit([$1], ]m4_dquote(m4_defn([m4_cr_symbols2]))[), [],
[m4_if(m4_len(m4_translit(m4_format([[%.1s]], [$1]), ]]dnl
m4_dquote(m4_dquote(m4_defn([m4_cr_symbols1])))[[)), [0], [$2], [$3])],
[$3])])
# AS_LITERAL_IF(EXPRESSION, IF-LITERAL, IF-NOT-LITERAL)
# -----------------------------------------------------
# If EXPRESSION has shell indirections ($var or `expr`), expand