Exploit shell arithmetic expansion and ${#var}.

* libltdl/m4/libtool.m4 (_LT_CHECK_SHELL_FEATURES): Also check
for arithmetic expansion, and ${#var}.
(_LT_PROG_XSI_SHELLFNS): Define func_arith and func_len
accordingly, falling back on 'expr'.  Note that the argument to
func_len may not start with a hyphen.  In the pre-Posix
fallback, take care not to rely on the exit status of the
variable assignment (not portable), but set the length to
$max_cmd_len instead.
* libltdl/config/ltmain.m4sh (func_mode_link): Use func_arith
and func_len throughout for integer arithmetic, fixing
quadratical amount of counting for reloadable object and
piecewise archive linking.  Change all comparisons with
max_cmd_len to test for smaller, non-equal length.
* THANKS: Update.
Suggested by Roland Mainz.

Signed-off-by: Ralf Wildenhues <Ralf.Wildenhues@gmx.de>

diff --git a/ChangeLog b/ChangeLog
index 63760ce10ecbf452bc74493f8aa2ccb0f1581f58..d482b1652b95e310dcd23e0d79772f51ea0f0e67 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,22 @@
 2008-04-19  Ralf Wildenhues  <Ralf.Wildenhues@gmx.de>
 
+       Exploit shell arithmetic expansion and ${#var}.
+       * libltdl/m4/libtool.m4 (_LT_CHECK_SHELL_FEATURES): Also check
+       for arithmetic expansion, and ${#var}.
+       (_LT_PROG_XSI_SHELLFNS): Define func_arith and func_len
+       accordingly, falling back on 'expr'.  Note that the argument to
+       func_len may not start with a hyphen.  In the pre-Posix
+       fallback, take care not to rely on the exit status of the
+       variable assignment (not portable), but set the length to
+       $max_cmd_len instead.
+       * libltdl/config/ltmain.m4sh (func_mode_link): Use func_arith
+       and func_len throughout for integer arithmetic, fixing
+       quadratical amount of counting for reloadable object and
+       piecewise archive linking.  Change all comparisons with
+       max_cmd_len to test for smaller, non-equal length.
+       * THANKS: Update.
+       Suggested by Roland Mainz.
+
        * libltdl/config/ltmain.m4sh (func_mode_compile): Avoid
        redundant removal of old output files before compilation.
        Do not remove $obj until we have successfully grabbed the

diff --git a/THANKS b/THANKS
index 236bbaba0451883c6f10ba61701d59a98d0461c8..3295b879351a8e6113f7ee845e55dee9a4d9742c 100644 (file)
--- a/THANKS
+++ b/THANKS
@@ -120,6 +120,7 @@
   Ralf Menzel                  menzel@ls6.cs.uni-dortmund.de
   Robert Ögren                        lists@roboros.com
   Roberto Bagnara              bagnara@cs.unipr.it
+  Roland Mainz                 roland.mainz@nrubsig.org
   Sebastian Wilhelmi           wilhelmi@ira.uka.de
   Simon Josefsson              jas@extundo.com
   Stephan Kulow                        coolo@kde.org

diff --git a/libltdl/config/ltmain.m4sh b/libltdl/config/ltmain.m4sh
index 8c5c45cfa46ff0239f1aa159b671f90beb97bb98..30e70eca0c823df55c68a19eaed5d0952370b7bf 100644 (file)
--- a/libltdl/config/ltmain.m4sh
+++ b/libltdl/config/ltmain.m4sh
@@ -2187,7 +2187,8 @@ func_extract_archives ()
       while :; do
         case " $extracted_archives " in
        *" $my_xlib_u "*)
-         extracted_serial=`expr $extracted_serial + 1`
+         func_arith $extracted_serial + 1
+         extracted_serial=$func_arith_result
          my_xlib_u=lt$extracted_serial-$my_xlib ;;
        *) break ;;
        esac
@@ -4656,7 +4657,8 @@ func_mode_link ()
              # bleh windows
              case $host in
              *cygwin* | mingw*)
-               major=`expr $current - $age`
+               func_arith $current - $age
+               major=$func_arith_result
                versuffix="-$major"
                ;;
              esac
@@ -5219,7 +5221,8 @@ func_mode_link ()
          #
          case $version_type in
          darwin|linux|osf|windows|none)
-           current=`expr $number_major + $number_minor`
+           func_arith $number_major + $number_minor
+           current=$func_arith_result
            age="$number_minor"
            revision="$number_revision"
            ;;
@@ -5229,7 +5232,8 @@ func_mode_link ()
            age="0"
            ;;
          irix|nonstopux)
-           current=`expr $number_major + $number_minor`
+           func_arith $number_major + $number_minor
+           current=$func_arith_result
            age="$number_minor"
            revision="$number_minor"
            lt_irix_increment=no
@@ -5283,10 +5287,12 @@ func_mode_link ()
        darwin)
          # Like Linux, but with the current version available in
          # verstring for coding it into the library header
-         major=.`expr $current - $age`
+         func_arith $current - $age
+         major=.$func_arith_result
          versuffix="$major.$age.$revision"
          # Darwin ld doesn't like 0 for these options...
-         minor_current=`expr $current + 1`
+         func_arith $current + 1
+         minor_current=$func_arith_result
          xlcverstring="${wl}-compatibility_version ${wl}$minor_current ${wl}-current_version ${wl}$minor_current.$revision"
          verstring="-compatibility_version $minor_current -current_version $minor_current.$revision"
          ;;
@@ -5303,10 +5309,11 @@ func_mode_link ()
 
        irix | nonstopux)
          if test "X$lt_irix_increment" = "Xno"; then
-           major=`expr $current - $age`
+           func_arith $current - $age
          else
-           major=`expr $current - $age + 1`
+           func_arith $current - $age + 1
          fi
+         major=$func_arith_result
 
          case $version_type in
            nonstopux) verstring_prefix=nonstopux ;;
@@ -5317,8 +5324,10 @@ func_mode_link ()
          # Add in all the interfaces that we are compatible with.
          loop=$revision
          while test "$loop" -ne 0; do
-           iface=`expr $revision - $loop`
-           loop=`expr $loop - 1`
+           func_arith $revision - $loop
+           iface=$func_arith_result
+           func_arith $loop - 1
+           loop=$func_arith_result
            verstring="$verstring_prefix$major.$iface:$verstring"
          done
 
@@ -5328,20 +5337,24 @@ func_mode_link ()
          ;;
 
        linux)
-         major=.`expr $current - $age`
+         func_arith $current - $age
+         major=.$func_arith_result
          versuffix="$major.$age.$revision"
          ;;
 
        osf)
-         major=.`expr $current - $age`
+         func_arith $current - $age
+         major=.$func_arith_result
          versuffix=".$current.$age.$revision"
          verstring="$current.$age.$revision"
 
          # Add in all the interfaces that we are compatible with.
          loop=$age
          while test "$loop" -ne 0; do
-           iface=`expr $current - $loop`
-           loop=`expr $loop - 1`
+           func_arith $current - $loop
+           iface=$func_arith_result
+           func_arith $loop - 1
+           loop=$func_arith_result
            verstring="$verstring:${iface}.0"
          done
 
@@ -5362,7 +5375,8 @@ func_mode_link ()
        windows)
          # Use '-' rather than '.', since we only want one
          # extension on DOS 8.3 filesystems.
-         major=`expr $current - $age`
+         func_arith $current - $age
+         major=$func_arith_result
          versuffix="-$major"
          ;;
 
@@ -6010,8 +6024,9 @@ EOF
            for cmd in $cmds; do
              IFS="$save_ifs"
              eval cmd=\"$cmd\"
-             if len=`expr "X$cmd" : ".*"` &&
-              test "$len" -le "$max_cmd_len" || test "$max_cmd_len" -le -1; then
+             func_len " $cmd"
+             len=$func_len_result
+             if test "$len" -lt "$max_cmd_len" || test "$max_cmd_len" -le -1; then
                func_show_eval "$cmd" 'exit $?'
                skipped_export=false
              else
@@ -6114,8 +6129,9 @@ EOF
        fi
 
        if test "X$skipped_export" != "X:" &&
-          len=`expr "X$test_cmds" : ".*" 2>/dev/null` &&
-          test "$len" -le "$max_cmd_len" || test "$max_cmd_len" -le -1; then
+          func_len " $test_cmds" &&
+          len=$func_len_result &&
+          test "$len" -lt "$max_cmd_len" || test "$max_cmd_len" -le -1; then
          :
        else
          # The command line is too long to link in one step, link piecewise
@@ -6175,14 +6191,20 @@ EOF
            if test -n "$save_libobjs"; then
              func_verbose "creating reloadable object files..."
              output=$output_objdir/$output_la-${k}.$objext
+             eval test_cmds=\"$reload_cmds\"
+             func_len " $test_cmds"
+             len0=$func_len_result
+             len=$len0
+
              # Loop over the list of objects to be linked.
              for obj in $save_libobjs
              do
-               eval test_cmds=\"$reload_cmds $objlist $last_robj\"
+               func_len " $obj"
+               func_arith $len + $func_len_result
+               len=$func_arith_result
                if test "X$objlist" = X ||
-                  { len=`expr "X$test_cmds" : ".*" 2>/dev/null` &&
-                    test "$len" -le "$max_cmd_len"; }; then
-                 objlist="$objlist $obj"
+                  test "$len" -lt "$max_cmd_len"; then
+                 func_append objlist " $obj"
                else
                  # The command $test_cmds is almost too long, add a
                  # command to the queue.
@@ -6195,10 +6217,13 @@ EOF
                    eval concat_cmds=\"\$concat_cmds~$reload_cmds $objlist $last_robj~\$RM $last_robj\"
                  fi
                  last_robj=$output_objdir/$output_la-${k}.$objext
-                 k=`expr $k + 1`
+                 func_arith $k + 1
+                 k=$func_arith_result
                  output=$output_objdir/$output_la-${k}.$objext
                  objlist=$obj
-                 len=1
+                 func_len " $last_robj"
+                 func_arith $len0 + $func_len_result
+                 len=$func_arith_result
                fi
              done
              # Handle the remaining objects by creating one last
@@ -6933,7 +6958,8 @@ EOF
                # Make sure we don't pick an alternate name that also
                # overlaps.
                newobj=lt$counter-$objbase
-               counter=`expr $counter + 1`
+               func_arith $counter + 1
+               counter=$func_arith_result
                case " $oldobjs " in
                *[\ /]"$newobj "*) ;;
                *) if test ! -f "$gentop/$newobj"; then break; fi ;;
@@ -6948,8 +6974,9 @@ EOF
        fi
        eval cmds=\"$old_archive_cmds\"
 
-       if len=`expr "X$cmds" : ".*" 2>/dev/null` &&
-          test "$len" -le "$max_cmd_len" || test "$max_cmd_len" -le -1; then
+       func_len " $cmds"
+       len=$func_len_result
+       if test "$len" -lt "$max_cmd_len" || test "$max_cmd_len" -le -1; then
          cmds=$old_archive_cmds
        else
          # the command line is too long to link in one step, link in parts
@@ -6959,18 +6986,23 @@ EOF
          objlist=
          concat_cmds=
          save_oldobjs=$oldobjs
+         oldobjs=
          # Is there a better way of finding the last object in the list?
          for obj in $save_oldobjs
          do
            last_oldobj=$obj
          done
+         eval test_cmds=\"$old_archive_cmds\"
+         func_len " $test_cmds"
+         len0=$func_len_result
+         len=$len0
          for obj in $save_oldobjs
          do
-           oldobjs="$objlist $obj"
-           objlist="$objlist $obj"
-           eval test_cmds=\"$old_archive_cmds\"
-           if len=`expr "X$test_cmds" : ".*" 2>/dev/null` &&
-              test "$len" -le "$max_cmd_len"; then
+           func_len " $obj"
+           func_arith $len + $func_len_result
+           len=$func_arith_result
+           func_append objlist " $obj"
+           if test "$len" -lt "$max_cmd_len"; then
              :
            else
              # the above command should be used before it gets too long
@@ -6981,6 +7013,7 @@ EOF
              test -z "$concat_cmds" || concat_cmds=$concat_cmds~
              eval concat_cmds=\"\${concat_cmds}$old_archive_cmds\"
              objlist=
+             len=$len0
            fi
          done
          RANLIB=$save_RANLIB

diff --git a/libltdl/m4/libtool.m4 b/libltdl/m4/libtool.m4
index 1fc9ccf8d7aab9cabf7f8c1d8769b2e694629db9..cdab37837d9928c9e0845ef18c97ba9125371639 100644 (file)
--- a/libltdl/m4/libtool.m4
+++ b/libltdl/m4/libtool.m4
@@ -7054,7 +7054,9 @@ m4_defun([_LT_CHECK_SHELL_FEATURES],
 xsi_shell=no
 ( _lt_dummy="a/b/c"
   test "${_lt_dummy##*/},${_lt_dummy%/*},"${_lt_dummy%"$_lt_dummy"}, \
-      = c,a/b,, ) >/dev/null 2>&1 \
+      = c,a/b,, \
+    && eval 'test $(( 1 + 1 )) -eq 2 \
+    && test "${#_lt_dummy}" -eq 5' ) >/dev/null 2>&1 \
   && xsi_shell=yes
 AC_MSG_RESULT([$xsi_shell])
 _LT_CONFIG_LIBTOOL_INIT([xsi_shell='$xsi_shell'])
@@ -7173,6 +7175,19 @@ func_xform ()
   func_xform_result=${1%.*}.lo
 }
 
+# func_arith arithmetic-term...
+func_arith ()
+{
+  func_arith_result=$(( $[*] ))
+}
+
+# func_len string
+# STRING may not start with a hyphen.
+func_len ()
+{
+  func_len_result=${#1}
+}
+
 _LT_EOF
     ;;
   *) # Bourne compatible functions.
@@ -7240,6 +7255,20 @@ func_xform ()
 {
   func_xform_result=`$ECHO "X${1}" | $Xsed -e 's/\.[[^.]]*$/.lo/'`
 }
+
+# func_arith arithmetic-term...
+func_arith ()
+{
+  func_arith_result=`expr "$[@]"`
+}
+
+# func_len string
+# STRING may not start with a hyphen.
+func_len ()
+{
+  func_len_result=`expr "$[1]" : ".*" 2>/dev/null || echo $max_cmd_len`
+}
+
 _LT_EOF
 esac