Replace brain-dead Autoconf macros AC_ARG_{ENABLE,WITH} with something

that's actually useful, robust, consistent.

Better plan to generate aclocal.m4 as well: use m4 include directives,
rather than cat.

1 files changed, 138 insertions, 0 deletions

diff --git a/config/general.m4 b/config/general.m4
new file mode 100644
index 00000000000..2e17f2ba0bd
--- /dev/null
+++ b/config/general.m4
@@ -0,0 +1,138 @@
+# $Header: /cvsroot/pgsql/config/general.m4,v 1.1 2000/09/21 20:17:42 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.
+# The flaw in these is particularly that they only differentiate
+# between "given" and "not given" and do not provide enough help to
+# process arguments that only accept "yes/no", that require an
+# argument (other than "yes/no"), etc.
+#
+# The point of this implementation is to reduce code size and
+# redundancy in configure.in and to improve robustness and consistency
+# in the option evaluation code.
+
+
+# print an error message and exit (while running `autoconf')
+define([pgac_error],
+       [errprint(__file__:__line__[: error: $1
+])
+        m4exit(10)])
+
+
+# Convert type and name to shell variable name (e.g., "enable_long_strings")
+define([pgac_arg_to_variable],
+       [$1[]_[]patsubst($2, -, _)])
+
+
+# PGAC_ARG(TYPE, NAME, HELP-STRING,
+#          [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
+# and argument (or "yes", which is the same); similar for ACTION-IF-NO.
+
+AC_DEFUN([PGAC_ARG],
+[dnl Check arguments
+ifelse([$1], enable, ,
+        [$1], with, ,
+        [pgac_error([first argument of $0 must be `enable' or `with', not `$1'])])[]dnl
+define([pgac_variable], [pgac_arg_to_variable([$1], [$2])])[]dnl
+dnl Register help string, only if there is one
+ifelse([$3], [], [],
+[AC_DIVERT_PUSH(AC_DIVERSION_NOTICE)dnl
+ac_help="$ac_help
+[$3]"
+AC_DIVERT_POP()])dnl
+[#] Check whether --$1-$2 was given
+if test x"[$]{pgac_variable+set}" = xset; then
+  case [$]pgac_variable in
+    yes)
+      ifelse([$4], [], :, [$4])
+      ;;
+    no)
+      ifelse([$5], [], :, [$5])
+      ;;
+dnl Action if called with argument
+ifelse([$6], [], [],
+[    *)
+dnl Set up $withval or $enableval
+      $1[]val=[$]pgac_variable
+      $6
+      ;;
+])[]dnl
+  esac [#] [$]pgac_variable
+dnl Action if omitted
+ifelse([$7], [], [],
+[else
+  $7
+])[]dnl
+fi[]dnl
+undefine([pgac_variable])dnl
+])# PGAC_ARG
+
+
+# PGAC_ARG_BOOL(TYPE, NAME, DEFAULT, HELP-STRING, 
+#               [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".
+# (Consequently, one of ACTION-IF-YES and ACTION-IF-NO will always
+# execute.)
+
+AC_DEFUN([PGAC_ARG_BOOL],
+[PGAC_ARG([$1], [$2], [$4], [$5], [$6],
+          [AC_MSG_ERROR([no argument expected for --$1-$2 option])],
+          [ifelse([$3], yes, [pgac_arg_to_variable([$1], [$2])=yes
+$5],
+                  [$3], no,  [pgac_arg_to_variable([$1], [$2])=no
+$6],
+                  [pgac_error([third argument of $0 must be `yes' or `no', not `$3'])])])[]dnl
+])# PGAC_ARG_BOOL
+
+
+# PGAC_ARG_REQ(TYPE, NAME, HELP-STRING, [ACTION-IF-GIVEN], [ACTION-IF-NOT-GIVEN])
+# -------------------------------------------------------------------------------
+# This option will require an argument; "yes" or "no" will not be
+# accepted.
+
+AC_DEFUN([PGAC_ARG_REQ],
+[PGAC_ARG([$1], [$2], [$3],
+          [AC_MSG_ERROR([argument required for --$1-$2 option])],
+          [AC_MSG_ERROR([argument required for --$1-$2 option])],
+          [$4],
+          [$5])])# PGAC_ARG_REQ
+
+
+# PGAC_ARG_OPTARG(TYPE, NAME, HELP-STRING, [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
+# called with argument, set enable_variable to "yes" and execute
+# ARG-ACTION. Additionally, execute ACTION-ENABLED if we ended up with
+# "yes" either way, else ACTION-DISABLED.
+#
+# The intent is to allow enabling a feature, and optionally pass an
+# additional piece of information.
+
+AC_DEFUN([PGAC_ARG_OPTARG],
+[PGAC_ARG([$1], [$2], [$3], [$4], [],
+          [pgac_arg_to_variable([$1], [$2])=yes
+$5],
+          [pgac_arg_to_variable([$1], [$2])=no])
+dnl Add this code only if there's a ACTION-ENABLED or ACTION-DISABLED.
+ifelse([$6[]$7], [], [],
+[
+if test "[$]pgac_arg_to_variable([$1], [$2])" = yes; then
+  ifelse([$6], [], :, [$6])
+ifelse([$7], [], [],
+[else
+  $7
+])[]dnl
+fi
+])[]dnl
+])# PGAC_ARG_OPTARG