>From c283b8a8e7540b65fd7a7d32fceec6ed42b5b2a7 Mon Sep 17 00:00:00 2001
From: Pavel Raiskup <address@hidden>
Date: Mon, 5 Oct 2015 13:16:08 +0200
Subject: [PATCH 2/2] libbtool: optimize parse-options calls

Its not necessary to re-escape-for-eval in each function in the
hook-able function tree -- usually is enough if the leaf function
executes func_quote_for_eval() and its caller just re-uses the
CALLEE_return value.

* gl/build-aux/options-parser (func_run_hooks): Propagate 0 return
code down to caller if any $_G_hook succeeded.  Don't re-quote
the result as that has already been done by the succeeding hook
itself.
(func_parse_options): Quote only if we changed something and
use appropriate return code.
(func_validate_options): Likewise.
(func_options_prep): Likewise.
(func_options_finish): New hook-caller for 'func_options' hooks.
(func_options): Propagate return value down to top-level caller,
but pay attention we have always set $func_options_result.
* build-aux/ltmain.in (libtool_options_prep): Quote only if we
changed something and use appropriate return code.
(libtool_parse_options): Likewise.
* bootstrap: Sync gl/build-aux/with option-parser.
---
 bootstrap                   | 128 +++++++++++++++++++++++++++++++++-----------
 build-aux/ltmain.in         |  33 +++++++++---
 gl/build-aux/options-parser | 128 +++++++++++++++++++++++++++++++++-----------
 3 files changed, 220 insertions(+), 69 deletions(-)

diff --git a/bootstrap b/bootstrap
index 2649478..c4de711 100755
--- a/bootstrap
+++ b/bootstrap
@@ -1744,10 +1744,17 @@ func_remove_hook ()
 # than a whitespace-delimited list of legal shell function names, and
 # no effort is wasted trying to catch shell meta-characters or preserve
 # whitespace.
+# If at least one hook returns 0 (exit success) upon execution,
+# func_run_hooks () returns zero too.  Otherwise 1 is returned.
+# All hooks are expected to correctly return $HOOKNAME_result variable
+# upon success exection.  The output variable $func_run_hooks_result
+# is set to latest (successful) $HOOKNAME_result.
 func_run_hooks ()
 {
     $debug_cmd
 
+    _G_rc_run_hooks=false
+
     case " $hookable_fns " in
       *" $1 "*) ;;
       *) func_fatal_error "'$1' does not support hook funcions.n" ;;
@@ -1756,16 +1763,24 @@ func_run_hooks ()
     eval _G_hook_fns=\$$1_hooks; shift
 
     for _G_hook in $_G_hook_fns; do
-      eval $_G_hook '"$@"'
+      _G_hook_unchanged=${_G_hook}_unchanged
+      eval $_G_hook_unchanged=false
 
-      # store returned options list back into positional
-      # parameters for next 'cmd' execution.
-      eval _G_hook_result=\$${_G_hook}_result
-      eval set dummy "$_G_hook_result"; shift
+      if eval $_G_hook '"$@"'; then
+          # store returned options list back into positional
+          # parameters for next 'cmd' execution.
+          eval _G_hook_result=\$${_G_hook}_result
+          eval set dummy "$_G_hook_result"; shift
+          _G_rc_run_hooks=true
+      fi
     done
 
-    func_quote_for_eval ${1+"$@"}
-    func_run_hooks_result=$func_quote_for_eval_result
+    if $_G_rc_run_hooks; then
+        # No need to re-quote by func_quoteh
+        func_run_hooks_result=$_G_hook_result
+    fi
+
+    $_G_rc_run_hooks
 }
 
 
@@ -1839,6 +1854,24 @@ func_run_hooks ()
 # multiple option parsing hooks can be added safely.
 
 
+# func_options_finish [ARG]...
+# ----------------------------
+# All finishing suff required after the option parse loop.  This executes
+# all 'func_options' hooks.
+func_options_finish ()
+{
+    $debug_cmd
+
+    _G_func_options_finish_exit=false
+    if func_run_hooks func_options ${1+"$@"}; then
+      func_options_finish_result=$func_run_hooks_result
+      _G_func_options_finish_exit=:
+    fi
+
+    $_G_func_options_finish_exit
+}
+
+
 # func_options [ARG]...
 # ---------------------
 # All the functions called inside func_options are hookable. See the
@@ -1848,17 +1881,26 @@ func_options ()
 {
     $debug_cmd
 
-    func_options_prep ${1+"$@"}
-    eval func_parse_options \
-        ${func_options_prep_result+"$func_options_prep_result"}
-    eval func_validate_options \
-        ${func_parse_options_result+"$func_parse_options_result"}
+    _G_rc_options=false
 
-    eval func_run_hooks func_options \
-        ${func_validate_options_result+"$func_validate_options_result"}
+    for my_func in options_prep parse_options validate_options options_finish
+    do
+      if eval func_$my_func '${1+"$@"}'; then
+        eval _G_res_var='$'"func_${my_func}_result"
+        eval set dummy "$_G_res_var" ; shift
+        _G_rc_options=:
+      fi
+    done
 
-    # save modified positional parameters for caller
-    func_options_result=$func_run_hooks_result
+    if $_G_rc_options; then
+      func_options_result=$_G_res_var
+    else
+      # As a top-level function, we need *always* set the *_result
+      func_quote_for_eval ${1+"$@"}
+      func_options_result=$func_quote_for_eval_result
+    fi
+
+    $_G_rc_options
 }
 
 
@@ -1869,7 +1911,9 @@ func_options ()
 # positional parameters.  If a hook function modifies that list, and
 # needs to propogate that back to rest of this script, then the complete
 # modified list must be put in 'func_run_hooks_result' before
-# returning.
+# returning and 0 returned.  If no changes were done, script might return
+# 1 and caller of the hook will not read the 'func_run_hooks_result'
+# value.
 func_hookable func_options_prep
 func_options_prep ()
 {
@@ -1879,10 +1923,14 @@ func_options_prep ()
     opt_verbose=false
     opt_warning_types=
 
-    func_run_hooks func_options_prep ${1+"$@"}
+    _G_rc_options_prep=false
+    if func_run_hooks func_options_prep ${1+"$@"}; then
+        _G_rc_options_prep=:
+        # save modified positional parameters for caller
+        func_options_prep_result=$func_run_hooks_result
+    fi
 
-    # save modified positional parameters for caller
-    func_options_prep_result=$func_run_hooks_result
+    $_G_rc_options_prep
 }
 
 
@@ -1896,18 +1944,21 @@ func_parse_options ()
 
     func_parse_options_result=
 
+    _G_rc_parse_options=false
     # this just eases exit handling
     while test $# -gt 0; do
       # Defer to hook functions for initial option parsing, so they
       # get priority in the event of reusing an option name.
-      func_run_hooks func_parse_options ${1+"$@"}
-
-      # Adjust func_parse_options positional parameters to match
-      eval set dummy "$func_run_hooks_result"; shift
+      if func_run_hooks func_parse_options ${1+"$@"}; then
+          # Adjust func_parse_options positional parameters to match
+          eval set dummy "$func_run_hooks_result"; shift
+          _G_rc_parse_options=:
+      fi
 
       # Break out of the loop if we already parsed every option.
       test $# -gt 0 || break
 
+      _G_match_parse_options=:
       _G_opt=$1
       shift
       case $_G_opt in
@@ -1977,13 +2028,23 @@ func_parse_options ()
 
         --)           break ;;
         -*)           func_fatal_help "unrecognised option: '$_G_opt'" ;;
-        *)            set dummy "$_G_opt" ${1+"$@"}; shift; break ;;
+        *)            set dummy "$_G_opt" ${1+"$@"} ; shift
+                      _G_match_parse_options=false
+                      break
+                      ;;
       esac
+
+      $_G_match_parse_options && _G_rc_parse_options=:
     done
 
-    # save modified positional parameters for caller
-    func_quote_for_eval ${1+"$@"}
-    func_parse_options_result=$func_quote_for_eval_result
+
+    if $_G_rc_parse_options; then
+        # save modified positional parameters for caller
+        func_quote_for_eval ${1+"$@"}
+        func_parse_options_result=$func_quote_for_eval_result
+    fi
+
+    $_G_rc_parse_options
 }
 
 
@@ -1996,16 +2057,21 @@ func_validate_options ()
 {
     $debug_cmd
 
+    _G_rc_validate_options=false
+
     # Display all warnings if -W was not given.
     test -n "$opt_warning_types" || opt_warning_types=" $warning_categories"
 
-    func_run_hooks func_validate_options ${1+"$@"}
+    if func_run_hooks func_validate_options ${1+"$@"}; then
+      # save modified positional parameters for caller
+      func_validate_options_result=$func_run_hooks_result
+      _G_rc_validate_options=:
+    fi
 
     # Bail if the options were screwed!
     $exit_cmd $EXIT_FAILURE
 
-    # save modified positional parameters for caller
-    func_validate_options_result=$func_run_hooks_result
+    $_G_rc_validate_options
 }
 
 
diff --git a/build-aux/ltmain.in b/build-aux/ltmain.in
index 24acefd..e57042a 100644
--- a/build-aux/ltmain.in
+++ b/build-aux/ltmain.in
@@ -358,6 +358,8 @@ libtool_options_prep ()
     nonopt=
     preserve_args=
 
+    _G_rc_libtool_options_prep=:
+
     # Shorthand for --mode=foo, only valid as the first argument
     case $1 in
     clean|clea|cle|cl)
@@ -381,11 +383,18 @@ libtool_options_prep ()
     uninstall|uninstal|uninsta|uninst|unins|unin|uni|un|u)
       shift; set dummy --mode uninstall ${1+"$@"}; shift
       ;;
+    *)
+      _G_rc_libtool_options_prep=false
+      ;;
     esac
 
-    # Pass back the list of options.
-    func_quote_for_eval ${1+"$@"}
-    libtool_options_prep_result=$func_quote_for_eval_result
+    if $_G_rc_libtool_options_prep; then
+        # Pass back the list of options.
+        func_quote_for_eval ${1+"$@"}
+        libtool_options_prep_result=$func_quote_for_eval_result
+    fi
+
+    $_G_rc_libtool_options_prep
 }
 func_add_hook func_options_prep libtool_options_prep
 
@@ -397,9 +406,12 @@ libtool_parse_options ()
 {
     $debug_cmd
 
+    _G_rc_lt_parse_options=false
+
     # Perform our own loop to consume as many options as possible in
     # each iteration.
     while test $# -gt 0; do
+      _G_match_lt_parse_options=:
       _G_opt=$1
       shift
       case $_G_opt in
@@ -475,14 +487,21 @@ libtool_parse_options ()
                         ;;
 
 	# An option not handled by this hook function:
-        *)		set dummy "$_G_opt" ${1+"$@"};	shift; break  ;;
+        *)              set dummy "$_G_opt" ${1+"$@"} ; shift
+                        _G_match_lt_parse_options=false
+                        break
+                        ;;
       esac
+      $_G_match_lt_parse_options && _G_rc_lt_parse_options=:
     done
 
+    if $_G_rc_lt_parse_options; then
+        # save modified positional parameters for caller
+        func_quote_for_eval ${1+"$@"}
+        libtool_parse_options_result=$func_quote_for_eval_result
+    fi
 
-    # save modified positional parameters for caller
-    func_quote_for_eval ${1+"$@"}
-    libtool_parse_options_result=$func_quote_for_eval_result
+    $_G_rc_lt_parse_options
 }
 func_add_hook func_parse_options libtool_parse_options
 
diff --git a/gl/build-aux/options-parser b/gl/build-aux/options-parser
index d651f1d..73db1e3 100644
--- a/gl/build-aux/options-parser
+++ b/gl/build-aux/options-parser
@@ -157,10 +157,17 @@ func_remove_hook ()
 # than a whitespace-delimited list of legal shell function names, and
 # no effort is wasted trying to catch shell meta-characters or preserve
 # whitespace.
+# If at least one hook returns 0 (exit success) upon execution,
+# func_run_hooks () returns zero too.  Otherwise 1 is returned.
+# All hooks are expected to correctly return $HOOKNAME_result variable
+# upon success exection.  The output variable $func_run_hooks_result
+# is set to latest (successful) $HOOKNAME_result.
 func_run_hooks ()
 {
     $debug_cmd
 
+    _G_rc_run_hooks=false
+
     case " $hookable_fns " in
       *" $1 "*) ;;
       *) func_fatal_error "'$1' does not support hook funcions.n" ;;
@@ -169,16 +176,24 @@ func_run_hooks ()
     eval _G_hook_fns=\$$1_hooks; shift
 
     for _G_hook in $_G_hook_fns; do
-      eval $_G_hook '"$@"'
+      _G_hook_unchanged=${_G_hook}_unchanged
+      eval $_G_hook_unchanged=false
 
-      # store returned options list back into positional
-      # parameters for next 'cmd' execution.
-      eval _G_hook_result=\$${_G_hook}_result
-      eval set dummy "$_G_hook_result"; shift
+      if eval $_G_hook '"$@"'; then
+          # store returned options list back into positional
+          # parameters for next 'cmd' execution.
+          eval _G_hook_result=\$${_G_hook}_result
+          eval set dummy "$_G_hook_result"; shift
+          _G_rc_run_hooks=true
+      fi
     done
 
-    func_quote_for_eval ${1+"$@"}
-    func_run_hooks_result=$func_quote_for_eval_result
+    if $_G_rc_run_hooks; then
+        # No need to re-quote by func_quoteh
+        func_run_hooks_result=$_G_hook_result
+    fi
+
+    $_G_rc_run_hooks
 }
 
 
@@ -252,6 +267,24 @@ func_run_hooks ()
 # multiple option parsing hooks can be added safely.
 
 
+# func_options_finish [ARG]...
+# ----------------------------
+# All finishing suff required after the option parse loop.  This executes
+# all 'func_options' hooks.
+func_options_finish ()
+{
+    $debug_cmd
+
+    _G_func_options_finish_exit=false
+    if func_run_hooks func_options ${1+"$@"}; then
+      func_options_finish_result=$func_run_hooks_result
+      _G_func_options_finish_exit=:
+    fi
+
+    $_G_func_options_finish_exit
+}
+
+
 # func_options [ARG]...
 # ---------------------
 # All the functions called inside func_options are hookable. See the
@@ -261,17 +294,26 @@ func_options ()
 {
     $debug_cmd
 
-    func_options_prep ${1+"$@"}
-    eval func_parse_options \
-        ${func_options_prep_result+"$func_options_prep_result"}
-    eval func_validate_options \
-        ${func_parse_options_result+"$func_parse_options_result"}
+    _G_rc_options=false
 
-    eval func_run_hooks func_options \
-        ${func_validate_options_result+"$func_validate_options_result"}
+    for my_func in options_prep parse_options validate_options options_finish
+    do
+      if eval func_$my_func '${1+"$@"}'; then
+        eval _G_res_var='$'"func_${my_func}_result"
+        eval set dummy "$_G_res_var" ; shift
+        _G_rc_options=:
+      fi
+    done
 
-    # save modified positional parameters for caller
-    func_options_result=$func_run_hooks_result
+    if $_G_rc_options; then
+      func_options_result=$_G_res_var
+    else
+      # As a top-level function, we need *always* set the *_result
+      func_quote_for_eval ${1+"$@"}
+      func_options_result=$func_quote_for_eval_result
+    fi
+
+    $_G_rc_options
 }
 
 
@@ -282,7 +324,9 @@ func_options ()
 # positional parameters.  If a hook function modifies that list, and
 # needs to propogate that back to rest of this script, then the complete
 # modified list must be put in 'func_run_hooks_result' before
-# returning.
+# returning and 0 returned.  If no changes were done, script might return
+# 1 and caller of the hook will not read the 'func_run_hooks_result'
+# value.
 func_hookable func_options_prep
 func_options_prep ()
 {
@@ -292,10 +336,14 @@ func_options_prep ()
     opt_verbose=false
     opt_warning_types=
 
-    func_run_hooks func_options_prep ${1+"$@"}
+    _G_rc_options_prep=false
+    if func_run_hooks func_options_prep ${1+"$@"}; then
+        _G_rc_options_prep=:
+        # save modified positional parameters for caller
+        func_options_prep_result=$func_run_hooks_result
+    fi
 
-    # save modified positional parameters for caller
-    func_options_prep_result=$func_run_hooks_result
+    $_G_rc_options_prep
 }
 
 
@@ -309,18 +357,21 @@ func_parse_options ()
 
     func_parse_options_result=
 
+    _G_rc_parse_options=false
     # this just eases exit handling
     while test $# -gt 0; do
       # Defer to hook functions for initial option parsing, so they
       # get priority in the event of reusing an option name.
-      func_run_hooks func_parse_options ${1+"$@"}
-
-      # Adjust func_parse_options positional parameters to match
-      eval set dummy "$func_run_hooks_result"; shift
+      if func_run_hooks func_parse_options ${1+"$@"}; then
+          # Adjust func_parse_options positional parameters to match
+          eval set dummy "$func_run_hooks_result"; shift
+          _G_rc_parse_options=:
+      fi
 
       # Break out of the loop if we already parsed every option.
       test $# -gt 0 || break
 
+      _G_match_parse_options=:
       _G_opt=$1
       shift
       case $_G_opt in
@@ -390,13 +441,23 @@ func_parse_options ()
 
         --)           break ;;
         -*)           func_fatal_help "unrecognised option: '$_G_opt'" ;;
-        *)            set dummy "$_G_opt" ${1+"$@"}; shift; break ;;
+        *)            set dummy "$_G_opt" ${1+"$@"} ; shift
+                      _G_match_parse_options=false
+                      break
+                      ;;
       esac
+
+      $_G_match_parse_options && _G_rc_parse_options=:
     done
 
-    # save modified positional parameters for caller
-    func_quote_for_eval ${1+"$@"}
-    func_parse_options_result=$func_quote_for_eval_result
+
+    if $_G_rc_parse_options; then
+        # save modified positional parameters for caller
+        func_quote_for_eval ${1+"$@"}
+        func_parse_options_result=$func_quote_for_eval_result
+    fi
+
+    $_G_rc_parse_options
 }
 
 
@@ -409,16 +470,21 @@ func_validate_options ()
 {
     $debug_cmd
 
+    _G_rc_validate_options=false
+
     # Display all warnings if -W was not given.
     test -n "$opt_warning_types" || opt_warning_types=" $warning_categories"
 
-    func_run_hooks func_validate_options ${1+"$@"}
+    if func_run_hooks func_validate_options ${1+"$@"}; then
+      # save modified positional parameters for caller
+      func_validate_options_result=$func_run_hooks_result
+      _G_rc_validate_options=:
+    fi
 
     # Bail if the options were screwed!
     $exit_cmd $EXIT_FAILURE
 
-    # save modified positional parameters for caller
-    func_validate_options_result=$func_run_hooks_result
+    $_G_rc_validate_options
 }
 
 
-- 
2.5.0