Use Autoconf provided AS_HELP_STRING macro to automatically format and

align strings in the --help output.  Do this through our abstraction layer
to eliminate redundancy and randomness in configure.in.

config/general.m4

-# $PostgreSQL: pgsql/config/general.m4,v 1.9 2006/11/30 22:21:23 tgl Exp $
+# $PostgreSQL: pgsql/config/general.m4,v 1.10 2008/10/29 09:27:24 petere Exp $
 
 # This file defines new macros to process configure command line
 # arguments, to replace the brain-dead AC_ARG_WITH and AC_ARG_ENABLE.
@@ -17,14 +17,19 @@ m4_define([pgac_arg_to_variable],
           [$1[]_[]patsubst($2, -, _)])
 
 
-# PGAC_ARG(TYPE, NAME, HELP-STRING,
+# PGAC_ARG(TYPE, NAME, HELP-STRING-LHS-EXTRA, HELP-STRING-RHS,
 #          [ACTION-IF-YES], [ACTION-IF-NO], [ACTION-IF-ARG],
 #          [ACTION-IF-OMITTED])
-# ----------------------------------------------------------
+# ------------------------------------------------------------
 # This is the base layer. TYPE is either "with" or "enable", depending
-# on what you like. NAME is the rest of the option name, HELP-STRING
-# as usual. ACTION-IF-YES is executed if the option is given without
-# an argument (or "yes", which is the same); similar for ACTION-IF-NO.
+# on what you like.  NAME is the rest of the option name.
+# HELP-STRING-LHS-EXTRA is a string to append to the option name on
+# the left-hand side of the help output, e.g., an argument name.  If
+# set to "-", append nothing, but let the option appear in the
+# negative form (disable/without).  HELP-STRING-RHS is the option
+# description, for the right-hand side of the help output.
+# ACTION-IF-YES is executed if the option is given without an argument
+# (or "yes", which is the same); similar for ACTION-IF-NO.
 
 AC_DEFUN([PGAC_ARG],
 [
@@ -32,37 +37,37 @@ pgac_args="$pgac_args pgac_arg_to_variable([$1],[$2])"
 m4_case([$1],
 
 enable, [
-AC_ARG_ENABLE([$2], [$3], [
+AC_ARG_ENABLE([$2], [AS_HELP_STRING([--]m4_if($3, -, disable, enable)[-$2]m4_if($3, -, , $3), [$4])], [
   case [$]enableval in
     yes)
-      m4_default([$4], :)
+      m4_default([$5], :)
       ;;
     no)
-      m4_default([$5], :)
+      m4_default([$6], :)
       ;;
     *)
-      $6
+      $7
       ;;
   esac
 ],
-[$7])[]dnl AC_ARG_ENABLE
+[$8])[]dnl AC_ARG_ENABLE
 ],
 
 with, [
-AC_ARG_WITH([$2], [$3], [
+AC_ARG_WITH([$2], [AS_HELP_STRING([--]m4_if($3, -, without, with)[-$2]m4_if($3, -, , $3), [$4])], [
   case [$]withval in
     yes)
-      m4_default([$4], :)
+      m4_default([$5], :)
       ;;
     no)
-      m4_default([$5], :)
+      m4_default([$6], :)
       ;;
     *)
-      $6
+      $7
       ;;
   esac
 ],
-[$7])[]dnl AC_ARG_WITH
+[$8])[]dnl AC_ARG_WITH
 ],
 
 [m4_fatal([first argument of $0 must be 'enable' or 'with', not '$1'])]
@@ -86,9 +91,9 @@ AC_DEFUN([PGAC_ARG_CHECK],
   AC_MSG_WARN([option ignored: --$pgac_txt])
 done])# PGAC_ARG_CHECK
 
-# PGAC_ARG_BOOL(TYPE, NAME, DEFAULT, HELP-STRING, 
+# PGAC_ARG_BOOL(TYPE, NAME, DEFAULT, HELP-STRING-RHS,
 #               [ACTION-IF-YES], [ACTION-IF-NO])
-# -----------------------------------------------
+# ---------------------------------------------------
 # Accept a boolean option, that is, one that only takes yes or no.
 # ("no" is equivalent to "disable" or "without"). DEFAULT is what
 # should be done if the option is omitted; it should be "yes" or "no".
@@ -96,7 +101,13 @@ done])# PGAC_ARG_CHECK
 # execute.)
 
 AC_DEFUN([PGAC_ARG_BOOL],
-[PGAC_ARG([$1], [$2], [$4], [$5], [$6], 
+[dnl The following hack is necessary because in a few instances this
+dnl macro is called twice for the same option with different default
+dnl values.  But we only want it to appear once in the help.  We achieve
+dnl that by making the help string look the same, which is why we need to
+dnl save the default that was passed in previously.
+m4_define([_pgac_helpdefault], m4_ifdef([pgac_defined_$1_$2_bool], [m4_defn([pgac_defined_$1_$2_bool])], [$3]))dnl
+PGAC_ARG([$1], [$2], [m4_if(_pgac_helpdefault, yes, -)], [$4], [$5], [$6], 
           [AC_MSG_ERROR([no argument expected for --$1-$2 option])],
           [m4_case([$3],
                    yes, [pgac_arg_to_variable([$1], [$2])=yes
@@ -104,25 +115,28 @@ $5],
                    no,  [pgac_arg_to_variable([$1], [$2])=no
 $6],
                    [m4_fatal([third argument of $0 must be 'yes' or 'no', not '$3'])])])[]dnl
+m4_define([pgac_defined_$1_$2_bool], [$3])dnl
 ])# PGAC_ARG_BOOL
 
 
-# PGAC_ARG_REQ(TYPE, NAME, HELP-STRING, [ACTION-IF-GIVEN], [ACTION-IF-NOT-GIVEN])
-# -------------------------------------------------------------------------------
+# PGAC_ARG_REQ(TYPE, NAME, HELP-ARGNAME, HELP-STRING-RHS,
+#              [ACTION-IF-GIVEN], [ACTION-IF-NOT-GIVEN])
+# -------------------------------------------------------
 # This option will require an argument; "yes" or "no" will not be
-# accepted.
+# accepted.  HELP-ARGNAME is a name for the argument for the help output.
 
 AC_DEFUN([PGAC_ARG_REQ],
-[PGAC_ARG([$1], [$2], [$3],
+[PGAC_ARG([$1], [$2], [=$3], [$4],
           [AC_MSG_ERROR([argument required for --$1-$2 option])],
           [AC_MSG_ERROR([argument required for --$1-$2 option])],
-          [$4],
-          [$5])])# PGAC_ARG_REQ
+          [$5],
+          [$6])])# PGAC_ARG_REQ
 
 
-# PGAC_ARG_OPTARG(TYPE, NAME, HELP-STRING, [DEFAULT-ACTION], [ARG-ACTION]
+# PGAC_ARG_OPTARG(TYPE, NAME, HELP-ARGNAME, HELP-STRING-RHS,
+#                 [DEFAULT-ACTION], [ARG-ACTION],
 #                 [ACTION-ENABLED], [ACTION-DISABLED])
-# -----------------------------------------------------------------------
+# ----------------------------------------------------------
 # This will create an option that behaves as follows: If omitted, or
 # called with "no", then set the enable_variable to "no" and do
 # nothing else. If called with "yes", then execute DEFAULT-ACTION. If
@@ -134,18 +148,18 @@ AC_DEFUN([PGAC_ARG_REQ],
 # additional piece of information.
 
 AC_DEFUN([PGAC_ARG_OPTARG],
-[PGAC_ARG([$1], [$2], [$3], [$4], [],
+[PGAC_ARG([$1], [$2], [@<:@=$3@:>@], [$4], [$5], [],
           [pgac_arg_to_variable([$1], [$2])=yes
-$5],
+$6],
           [pgac_arg_to_variable([$1], [$2])=no])
 dnl Add this code only if there's a ACTION-ENABLED or ACTION-DISABLED.
-m4_ifval([$6[]$7],
+m4_ifval([$7[]$8],
 [
 if test "[$]pgac_arg_to_variable([$1], [$2])" = yes; then
-  m4_default([$6], :)
-m4_ifval([$7],
+  m4_default([$7], :)
+m4_ifval([$8],
 [else
-  $7
+  $8
 ])[]dnl
 fi
 ])[]dnl

configure

@@ -1353,10 +1353,13 @@ if test -n "$ac_init_help"; then
 Optional Features:
   --disable-FEATURE       do not include FEATURE (same as --enable-FEATURE=no)
   --enable-FEATURE[=ARG]  include FEATURE [ARG=yes]
-  --disable-integer-datetimes  disable 64-bit integer date/time support
-  --enable-nls[=LANGUAGES]  enable Native Language Support
+  --disable-integer-datetimes
+                          disable 64-bit integer date/time support
+  --enable-nls[=LANGUAGES]
+                          enable Native Language Support
   --disable-shared        do not build shared libraries
-  --disable-rpath         do not embed shared library search path in executables
+  --disable-rpath         do not embed shared library search path in
+                          executables
   --disable-spinlocks     do not use spinlocks
   --enable-debug          build with debugging symbols (-g)
   --enable-profiling      build with profiling enabled
@@ -1365,7 +1368,8 @@ Optional Features:
   --enable-depend         turn on automatic dependency tracking
   --enable-cassert        enable assertion checks (for debugging)
   --enable-thread-safety  make client libraries thread-safe
-  --enable-thread-safety-force  force thread-safety despite thread test failure
+  --enable-thread-safety-force
+                          force thread-safety despite thread test failure
   --disable-float4-byval  disable float4 passed by value
   --disable-float8-byval  disable float8 passed by value
   --disable-largefile     omit support for large files
@@ -1373,32 +1377,40 @@ Optional Features:
 Optional Packages:
   --with-PACKAGE[=ARG]    use PACKAGE [ARG=yes]
   --without-PACKAGE       do not use PACKAGE (same as --with-PACKAGE=no)
-
+  --with-template=NAME    override operating system template
   --with-includes=DIRS    look for additional header files in DIRS
   --with-libraries=DIRS   look for additional libraries in DIRS
   --with-libs=DIRS        alternative spelling of --with-libraries
   --with-pgport=PORTNUM   set default port number [5432]
-  --with-blocksize=BLOCKSIZE  set table block size in kB [8]
+  --with-blocksize=BLOCKSIZE
+                          set table block size in kB [8]
   --with-segsize=SEGSIZE  set table segment size in GB [1]
-  --with-wal-blocksize=BLOCKSIZE  set WAL block size in kB [8]
-  --with-wal-segsize=SEGSIZE  set WAL segment size in MB [16]
+  --with-wal-blocksize=BLOCKSIZE
+                          set WAL block size in kB [8]
+  --with-wal-segsize=SEGSIZE
+                          set WAL segment size in MB [16]
+  --with-CC=CMD           set compiler (deprecated)
   --with-tcl              build Tcl modules (PL/Tcl)
   --with-tclconfig=DIR    tclConfig.sh is in DIR
   --with-perl             build Perl modules (PL/Perl)
   --with-python           build Python modules (PL/Python)
   --with-gssapi           build with GSSAPI support
   --with-krb5             build with Kerberos 5 support
-  --with-krb-srvnam=NAME  default service principal name in Kerberos [postgres]
+  --with-krb-srvnam=NAME  default service principal name in Kerberos
+                          [postgres]
   --with-pam              build with PAM support
   --with-ldap             build with LDAP support
   --with-bonjour          build with Bonjour support
   --with-openssl          build with OpenSSL support
   --without-readline      do not use GNU Readline nor BSD Libedit for editing
-  --with-libedit-preferred  prefer BSD Libedit over GNU Readline
-  --with-ossp-uuid        use OSSP UUID library when building contrib/uuid-ossp
+  --with-libedit-preferred
+                          prefer BSD Libedit over GNU Readline
+  --with-ossp-uuid        use OSSP UUID library when building
+                          contrib/uuid-ossp
   --with-libxml           build with XML support
   --with-libxslt          use XSLT support when building contrib/xml2
-  --with-system-tzdata=DIR  use system time zone data in DIR
+  --with-system-tzdata=DIR
+                          use system time zone data in DIR
   --without-zlib          do not use Zlib
   --with-gnu-ld           assume the C compiler uses GNU ld [default=no]