initial import of the C runtime

2 files changed, 622 insertions, 0 deletions

diff --git a/src/runtime/c/m4/ax_prog_doxygen.m4 b/src/runtime/c/m4/ax_prog_doxygen.m4
new file mode 100644
index 000000000..6334fd412
--- /dev/null
+++ b/src/runtime/c/m4/ax_prog_doxygen.m4
@@ -0,0 +1,533 @@
+# ===========================================================================
+#      http://www.gnu.org/software/autoconf-archive/ax_prog_doxygen.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   DX_INIT_DOXYGEN(PROJECT-NAME, DOXYFILE-PATH, [OUTPUT-DIR])
+#   DX_DOXYGEN_FEATURE(ON|OFF)
+#   DX_DOT_FEATURE(ON|OFF)
+#   DX_HTML_FEATURE(ON|OFF)
+#   DX_CHM_FEATURE(ON|OFF)
+#   DX_CHI_FEATURE(ON|OFF)
+#   DX_MAN_FEATURE(ON|OFF)
+#   DX_RTF_FEATURE(ON|OFF)
+#   DX_XML_FEATURE(ON|OFF)
+#   DX_PDF_FEATURE(ON|OFF)
+#   DX_PS_FEATURE(ON|OFF)
+#
+# DESCRIPTION
+#
+#   The DX_*_FEATURE macros control the default setting for the given
+#   Doxygen feature. Supported features are 'DOXYGEN' itself, 'DOT' for
+#   generating graphics, 'HTML' for plain HTML, 'CHM' for compressed HTML
+#   help (for MS users), 'CHI' for generating a seperate .chi file by the
+#   .chm file, and 'MAN', 'RTF', 'XML', 'PDF' and 'PS' for the appropriate
+#   output formats. The environment variable DOXYGEN_PAPER_SIZE may be
+#   specified to override the default 'a4wide' paper size.
+#
+#   By default, HTML, PDF and PS documentation is generated as this seems to
+#   be the most popular and portable combination. MAN pages created by
+#   Doxygen are usually problematic, though by picking an appropriate subset
+#   and doing some massaging they might be better than nothing. CHM and RTF
+#   are specific for MS (note that you can't generate both HTML and CHM at
+#   the same time). The XML is rather useless unless you apply specialized
+#   post-processing to it.
+#
+#   The macros mainly control the default state of the feature. The use can
+#   override the default by specifying --enable or --disable. The macros
+#   ensure that contradictory flags are not given (e.g.,
+#   --enable-doxygen-html and --enable-doxygen-chm,
+#   --enable-doxygen-anything with --disable-doxygen, etc.) Finally, each
+#   feature will be automatically disabled (with a warning) if the required
+#   programs are missing.
+#
+#   Once all the feature defaults have been specified, call DX_INIT_DOXYGEN
+#   with the following parameters: a one-word name for the project for use
+#   as a filename base etc., an optional configuration file name (the
+#   default is 'Doxyfile', the same as Doxygen's default), and an optional
+#   output directory name (the default is 'doxygen-doc').
+#
+#   Automake Support
+#
+#   The following is a template aminclude.am file for use with Automake.
+#   Make targets and variables values are controlled by the various
+#   DX_COND_* conditionals set by autoconf.
+#
+#   The provided targets are:
+#
+#     doxygen-doc: Generate all doxygen documentation.
+#
+#     doxygen-run: Run doxygen, which will generate some of the
+#                  documentation (HTML, CHM, CHI, MAN, RTF, XML)
+#                  but will not do the post processing required
+#                  for the rest of it (PS, PDF, and some MAN).
+#
+#     doxygen-man: Rename some doxygen generated man pages.
+#
+#     doxygen-ps:  Generate doxygen PostScript documentation.
+#
+#     doxygen-pdf: Generate doxygen PDF documentation.
+#
+#   Note that by default these are not integrated into the automake targets.
+#   If doxygen is used to generate man pages, you can achieve this
+#   integration by setting man3_MANS to the list of man pages generated and
+#   then adding the dependency:
+#
+#     $(man3_MANS): doxygen-doc
+#
+#   This will cause make to run doxygen and generate all the documentation.
+#
+#   The following variable is intended for use in Makefile.am:
+#
+#     DX_CLEANFILES = everything to clean.
+#
+#   Then add this variable to MOSTLYCLEANFILES.
+#
+#     ----- begin aminclude.am -------------------------------------
+#
+#     ## --------------------------------- ##
+#     ## Format-independent Doxygen rules. ##
+#     ## --------------------------------- ##
+#
+#     if DX_COND_doc
+#
+#     ## ------------------------------- ##
+#     ## Rules specific for HTML output. ##
+#     ## ------------------------------- ##
+#
+#     if DX_COND_html
+#
+#     DX_CLEAN_HTML = @DX_DOCDIR@/html
+#
+#     endif DX_COND_html
+#
+#     ## ------------------------------ ##
+#     ## Rules specific for CHM output. ##
+#     ## ------------------------------ ##
+#
+#     if DX_COND_chm
+#
+#     DX_CLEAN_CHM = @DX_DOCDIR@/chm
+#
+#     if DX_COND_chi
+#
+#     DX_CLEAN_CHI = @DX_DOCDIR@/@PACKAGE@.chi
+#
+#     endif DX_COND_chi
+#
+#     endif DX_COND_chm
+#
+#     ## ------------------------------ ##
+#     ## Rules specific for MAN output. ##
+#     ## ------------------------------ ##
+#
+#     if DX_COND_man
+#
+#     DX_CLEAN_MAN = @DX_DOCDIR@/man
+#
+#     endif DX_COND_man
+#
+#     ## ------------------------------ ##
+#     ## Rules specific for RTF output. ##
+#     ## ------------------------------ ##
+#
+#     if DX_COND_rtf
+#
+#     DX_CLEAN_RTF = @DX_DOCDIR@/rtf
+#
+#     endif DX_COND_rtf
+#
+#     ## ------------------------------ ##
+#     ## Rules specific for XML output. ##
+#     ## ------------------------------ ##
+#
+#     if DX_COND_xml
+#
+#     DX_CLEAN_XML = @DX_DOCDIR@/xml
+#
+#     endif DX_COND_xml
+#
+#     ## ----------------------------- ##
+#     ## Rules specific for PS output. ##
+#     ## ----------------------------- ##
+#
+#     if DX_COND_ps
+#
+#     DX_CLEAN_PS = @DX_DOCDIR@/@PACKAGE@.ps
+#
+#     DX_PS_GOAL = doxygen-ps
+#
+#     doxygen-ps: @DX_DOCDIR@/@PACKAGE@.ps
+#
+#     @DX_DOCDIR@/@PACKAGE@.ps: @DX_DOCDIR@/@PACKAGE@.tag
+#         cd @DX_DOCDIR@/latex; \
+#         rm -f *.aux *.toc *.idx *.ind *.ilg *.log *.out; \
+#         $(DX_LATEX) refman.tex; \
+#         $(MAKEINDEX_PATH) refman.idx; \
+#         $(DX_LATEX) refman.tex; \
+#         countdown=5; \
+#         while $(DX_EGREP) 'Rerun (LaTeX|to get cross-references right)' \
+#                           refman.log > /dev/null 2>&1 \
+#            && test $$countdown -gt 0; do \
+#             $(DX_LATEX) refman.tex; \
+#             countdown=`expr $$countdown - 1`; \
+#         done; \
+#         $(DX_DVIPS) -o ../@PACKAGE@.ps refman.dvi
+#
+#     endif DX_COND_ps
+#
+#     ## ------------------------------ ##
+#     ## Rules specific for PDF output. ##
+#     ## ------------------------------ ##
+#
+#     if DX_COND_pdf
+#
+#     DX_CLEAN_PDF = @DX_DOCDIR@/@PACKAGE@.pdf
+#
+#     DX_PDF_GOAL = doxygen-pdf
+#
+#     doxygen-pdf: @DX_DOCDIR@/@PACKAGE@.pdf
+#
+#     @DX_DOCDIR@/@PACKAGE@.pdf: @DX_DOCDIR@/@PACKAGE@.tag
+#         cd @DX_DOCDIR@/latex; \
+#         rm -f *.aux *.toc *.idx *.ind *.ilg *.log *.out; \
+#         $(DX_PDFLATEX) refman.tex; \
+#         $(DX_MAKEINDEX) refman.idx; \
+#         $(DX_PDFLATEX) refman.tex; \
+#         countdown=5; \
+#         while $(DX_EGREP) 'Rerun (LaTeX|to get cross-references right)' \
+#                           refman.log > /dev/null 2>&1 \
+#            && test $$countdown -gt 0; do \
+#             $(DX_PDFLATEX) refman.tex; \
+#             countdown=`expr $$countdown - 1`; \
+#         done; \
+#         mv refman.pdf ../@PACKAGE@.pdf
+#
+#     endif DX_COND_pdf
+#
+#     ## ------------------------------------------------- ##
+#     ## Rules specific for LaTeX (shared for PS and PDF). ##
+#     ## ------------------------------------------------- ##
+#
+#     if DX_COND_latex
+#
+#     DX_CLEAN_LATEX = @DX_DOCDIR@/latex
+#
+#     endif DX_COND_latex
+#
+#     .PHONY: doxygen-run doxygen-doc $(DX_PS_GOAL) $(DX_PDF_GOAL)
+#
+#     .INTERMEDIATE: doxygen-run $(DX_PS_GOAL) $(DX_PDF_GOAL)
+#
+#     doxygen-run: @DX_DOCDIR@/@PACKAGE@.tag
+#
+#     doxygen-doc: doxygen-run $(DX_PS_GOAL) $(DX_PDF_GOAL)
+#
+#     @DX_DOCDIR@/@PACKAGE@.tag: $(DX_CONFIG) $(pkginclude_HEADERS)
+#         rm -rf @DX_DOCDIR@
+#         $(DX_ENV) $(DX_DOXYGEN) $(srcdir)/$(DX_CONFIG)
+#
+#     DX_CLEANFILES = \
+#         @DX_DOCDIR@/@PACKAGE@.tag \
+#         -r \
+#         $(DX_CLEAN_HTML) \
+#         $(DX_CLEAN_CHM) \
+#         $(DX_CLEAN_CHI) \
+#         $(DX_CLEAN_MAN) \
+#         $(DX_CLEAN_RTF) \
+#         $(DX_CLEAN_XML) \
+#         $(DX_CLEAN_PS) \
+#         $(DX_CLEAN_PDF) \
+#         $(DX_CLEAN_LATEX)
+#
+#     endif DX_COND_doc
+#
+#     ----- end aminclude.am ---------------------------------------
+#
+# LICENSE
+#
+#   Copyright (c) 2009 Oren Ben-Kiki <oren@ben-kiki.org>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved. This file is offered as-is, without any
+#   warranty.
+
+#serial 10
+
+## ----------##
+## Defaults. ##
+## ----------##
+
+DX_ENV=""
+AC_DEFUN([DX_FEATURE_doc],  ON)
+AC_DEFUN([DX_FEATURE_dot],  ON)
+AC_DEFUN([DX_FEATURE_man],  OFF)
+AC_DEFUN([DX_FEATURE_html], ON)
+AC_DEFUN([DX_FEATURE_chm],  OFF)
+AC_DEFUN([DX_FEATURE_chi],  OFF)
+AC_DEFUN([DX_FEATURE_rtf],  OFF)
+AC_DEFUN([DX_FEATURE_xml],  OFF)
+AC_DEFUN([DX_FEATURE_pdf],  ON)
+AC_DEFUN([DX_FEATURE_ps],   ON)
+
+## --------------- ##
+## Private macros. ##
+## --------------- ##
+
+# DX_ENV_APPEND(VARIABLE, VALUE)
+# ------------------------------
+# Append VARIABLE="VALUE" to DX_ENV for invoking doxygen.
+AC_DEFUN([DX_ENV_APPEND], [AC_SUBST([DX_ENV], ["$DX_ENV $1='$2'"])])
+
+# DX_DIRNAME_EXPR
+# ---------------
+# Expand into a shell expression prints the directory part of a path.
+AC_DEFUN([DX_DIRNAME_EXPR],
+         [[expr ".$1" : '\(\.\)[^/]*$' \| "x$1" : 'x\(.*\)/[^/]*$']])
+
+# DX_IF_FEATURE(FEATURE, IF-ON, IF-OFF)
+# -------------------------------------
+# Expands according to the M4 (static) status of the feature.
+AC_DEFUN([DX_IF_FEATURE], [ifelse(DX_FEATURE_$1, ON, [$2], [$3])])
+
+# DX_REQUIRE_PROG(VARIABLE, PROGRAM)
+# ----------------------------------
+# Require the specified program to be found for the DX_CURRENT_FEATURE to work.
+AC_DEFUN([DX_REQUIRE_PROG], [
+AC_PATH_TOOL([$1], [$2])
+if test "$DX_FLAG_[]DX_CURRENT_FEATURE$$1" = 1; then
+    AC_MSG_WARN([$2 not found - will not DX_CURRENT_DESCRIPTION])
+    AC_SUBST(DX_FLAG_[]DX_CURRENT_FEATURE, 0)
+fi
+])
+
+# DX_TEST_FEATURE(FEATURE)
+# ------------------------
+# Expand to a shell expression testing whether the feature is active.
+AC_DEFUN([DX_TEST_FEATURE], [test "$DX_FLAG_$1" = 1])
+
+# DX_CHECK_DEPEND(REQUIRED_FEATURE, REQUIRED_STATE)
+# -------------------------------------------------
+# Verify that a required features has the right state before trying to turn on
+# the DX_CURRENT_FEATURE.
+AC_DEFUN([DX_CHECK_DEPEND], [
+test "$DX_FLAG_$1" = "$2" \
+|| AC_MSG_ERROR([doxygen-DX_CURRENT_FEATURE ifelse([$2], 1,
+                            requires, contradicts) doxygen-DX_CURRENT_FEATURE])
+])
+
+# DX_CLEAR_DEPEND(FEATURE, REQUIRED_FEATURE, REQUIRED_STATE)
+# ----------------------------------------------------------
+# Turn off the DX_CURRENT_FEATURE if the required feature is off.
+AC_DEFUN([DX_CLEAR_DEPEND], [
+test "$DX_FLAG_$1" = "$2" || AC_SUBST(DX_FLAG_[]DX_CURRENT_FEATURE, 0)
+])
+
+# DX_FEATURE_ARG(FEATURE, DESCRIPTION,
+#                CHECK_DEPEND, CLEAR_DEPEND,
+#                REQUIRE, DO-IF-ON, DO-IF-OFF)
+# --------------------------------------------
+# Parse the command-line option controlling a feature. CHECK_DEPEND is called
+# if the user explicitly turns the feature on (and invokes DX_CHECK_DEPEND),
+# otherwise CLEAR_DEPEND is called to turn off the default state if a required
+# feature is disabled (using DX_CLEAR_DEPEND). REQUIRE performs additional
+# requirement tests (DX_REQUIRE_PROG). Finally, an automake flag is set and
+# DO-IF-ON or DO-IF-OFF are called according to the final state of the feature.
+AC_DEFUN([DX_ARG_ABLE], [
+    AC_DEFUN([DX_CURRENT_FEATURE], [$1])
+    AC_DEFUN([DX_CURRENT_DESCRIPTION], [$2])
+    AC_ARG_ENABLE(doxygen-$1,
+                  [AS_HELP_STRING(DX_IF_FEATURE([$1], [--disable-doxygen-$1],
+                                                      [--enable-doxygen-$1]),
+                                  DX_IF_FEATURE([$1], [don't $2], [$2]))],
+                  [
+case "$enableval" in
+#(
+y|Y|yes|Yes|YES)
+    AC_SUBST([DX_FLAG_$1], 1)
+    $3
+;; #(
+n|N|no|No|NO)
+    AC_SUBST([DX_FLAG_$1], 0)
+;; #(
+*)
+    AC_MSG_ERROR([invalid value '$enableval' given to doxygen-$1])
+;;
+esac
+], [
+AC_SUBST([DX_FLAG_$1], [DX_IF_FEATURE([$1], 1, 0)])
+$4
+])
+if DX_TEST_FEATURE([$1]); then
+    $5
+    :
+fi
+if DX_TEST_FEATURE([$1]); then
+    AM_CONDITIONAL(DX_COND_$1, :)
+    $6
+    :
+else
+    AM_CONDITIONAL(DX_COND_$1, false)
+    $7
+    :
+fi
+])
+
+## -------------- ##
+## Public macros. ##
+## -------------- ##
+
+# DX_XXX_FEATURE(DEFAULT_STATE)
+# -----------------------------
+AC_DEFUN([DX_DOXYGEN_FEATURE], [AC_DEFUN([DX_FEATURE_doc],  [$1])])
+AC_DEFUN([DX_MAN_FEATURE],     [AC_DEFUN([DX_FEATURE_man],  [$1])])
+AC_DEFUN([DX_HTML_FEATURE],    [AC_DEFUN([DX_FEATURE_html], [$1])])
+AC_DEFUN([DX_CHM_FEATURE],     [AC_DEFUN([DX_FEATURE_chm],  [$1])])
+AC_DEFUN([DX_CHI_FEATURE],     [AC_DEFUN([DX_FEATURE_chi],  [$1])])
+AC_DEFUN([DX_RTF_FEATURE],     [AC_DEFUN([DX_FEATURE_rtf],  [$1])])
+AC_DEFUN([DX_XML_FEATURE],     [AC_DEFUN([DX_FEATURE_xml],  [$1])])
+AC_DEFUN([DX_XML_FEATURE],     [AC_DEFUN([DX_FEATURE_xml],  [$1])])
+AC_DEFUN([DX_PDF_FEATURE],     [AC_DEFUN([DX_FEATURE_pdf],  [$1])])
+AC_DEFUN([DX_PS_FEATURE],      [AC_DEFUN([DX_FEATURE_ps],   [$1])])
+
+# DX_INIT_DOXYGEN(PROJECT, [CONFIG-FILE], [OUTPUT-DOC-DIR])
+# ---------------------------------------------------------
+# PROJECT also serves as the base name for the documentation files.
+# The default CONFIG-FILE is "Doxyfile" and OUTPUT-DOC-DIR is "doxygen-doc".
+AC_DEFUN([DX_INIT_DOXYGEN], [
+
+# Files:
+AC_SUBST([DX_PROJECT], [$1])
+AC_SUBST([DX_CONFIG], [ifelse([$2], [], Doxyfile, [$2])])
+AC_SUBST([DX_DOCDIR], [ifelse([$3], [], doxygen-doc, [$3])])
+
+# Environment variables used inside doxygen.cfg:
+DX_ENV_APPEND(SRCDIR, $srcdir)
+DX_ENV_APPEND(PROJECT, $DX_PROJECT)
+DX_ENV_APPEND(DOCDIR, $DX_DOCDIR)
+DX_ENV_APPEND(VERSION, $PACKAGE_VERSION)
+
+# Doxygen itself:
+DX_ARG_ABLE(doc, [generate any doxygen documentation],
+            [],
+            [],
+            [DX_REQUIRE_PROG([DX_DOXYGEN], doxygen)
+             DX_REQUIRE_PROG([DX_PERL], perl)],
+            [DX_ENV_APPEND(PERL_PATH, $DX_PERL)])
+
+# Dot for graphics:
+DX_ARG_ABLE(dot, [generate graphics for doxygen documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [DX_REQUIRE_PROG([DX_DOT], dot)],
+            [DX_ENV_APPEND(HAVE_DOT, YES)
+             DX_ENV_APPEND(DOT_PATH, [`DX_DIRNAME_EXPR($DX_DOT)`])],
+            [DX_ENV_APPEND(HAVE_DOT, NO)])
+
+# Man pages generation:
+DX_ARG_ABLE(man, [generate doxygen manual pages],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [],
+            [DX_ENV_APPEND(GENERATE_MAN, YES)],
+            [DX_ENV_APPEND(GENERATE_MAN, NO)])
+
+# RTF file generation:
+DX_ARG_ABLE(rtf, [generate doxygen RTF documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [],
+            [DX_ENV_APPEND(GENERATE_RTF, YES)],
+            [DX_ENV_APPEND(GENERATE_RTF, NO)])
+
+# XML file generation:
+DX_ARG_ABLE(xml, [generate doxygen XML documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [],
+            [DX_ENV_APPEND(GENERATE_XML, YES)],
+            [DX_ENV_APPEND(GENERATE_XML, NO)])
+
+# (Compressed) HTML help generation:
+DX_ARG_ABLE(chm, [generate doxygen compressed HTML help documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [DX_REQUIRE_PROG([DX_HHC], hhc)],
+            [DX_ENV_APPEND(HHC_PATH, $DX_HHC)
+             DX_ENV_APPEND(GENERATE_HTML, YES)
+             DX_ENV_APPEND(GENERATE_HTMLHELP, YES)],
+            [DX_ENV_APPEND(GENERATE_HTMLHELP, NO)])
+
+# Seperate CHI file generation.
+DX_ARG_ABLE(chi, [generate doxygen seperate compressed HTML help index file],
+            [DX_CHECK_DEPEND(chm, 1)],
+            [DX_CLEAR_DEPEND(chm, 1)],
+            [],
+            [DX_ENV_APPEND(GENERATE_CHI, YES)],
+            [DX_ENV_APPEND(GENERATE_CHI, NO)])
+
+# Plain HTML pages generation:
+DX_ARG_ABLE(html, [generate doxygen plain HTML documentation],
+            [DX_CHECK_DEPEND(doc, 1) DX_CHECK_DEPEND(chm, 0)],
+            [DX_CLEAR_DEPEND(doc, 1) DX_CLEAR_DEPEND(chm, 0)],
+            [],
+            [DX_ENV_APPEND(GENERATE_HTML, YES)],
+            [DX_TEST_FEATURE(chm) || DX_ENV_APPEND(GENERATE_HTML, NO)])
+
+# PostScript file generation:
+DX_ARG_ABLE(ps, [generate doxygen PostScript documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [DX_REQUIRE_PROG([DX_LATEX], latex)
+             DX_REQUIRE_PROG([DX_MAKEINDEX], makeindex)
+             DX_REQUIRE_PROG([DX_DVIPS], dvips)
+             DX_REQUIRE_PROG([DX_EGREP], egrep)])
+
+# PDF file generation:
+DX_ARG_ABLE(pdf, [generate doxygen PDF documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [DX_REQUIRE_PROG([DX_PDFLATEX], pdflatex)
+             DX_REQUIRE_PROG([DX_MAKEINDEX], makeindex)
+             DX_REQUIRE_PROG([DX_EGREP], egrep)])
+
+# LaTeX generation for PS and/or PDF:
+if DX_TEST_FEATURE(ps) || DX_TEST_FEATURE(pdf); then
+    AM_CONDITIONAL(DX_COND_latex, :)
+    DX_ENV_APPEND(GENERATE_LATEX, YES)
+else
+    AM_CONDITIONAL(DX_COND_latex, false)
+    DX_ENV_APPEND(GENERATE_LATEX, NO)
+fi
+
+# Paper size for PS and/or PDF:
+AC_ARG_VAR(DOXYGEN_PAPER_SIZE,
+           [a4wide (default), a4, letter, legal or executive])
+case "$DOXYGEN_PAPER_SIZE" in
+#(
+"")
+    AC_SUBST(DOXYGEN_PAPER_SIZE, "")
+;; #(
+a4wide|a4|letter|legal|executive)
+    DX_ENV_APPEND(PAPER_SIZE, $DOXYGEN_PAPER_SIZE)
+;; #(
+*)
+    AC_MSG_ERROR([unknown DOXYGEN_PAPER_SIZE='$DOXYGEN_PAPER_SIZE'])
+;;
+esac
+
+#For debugging:
+#echo DX_FLAG_doc=$DX_FLAG_doc
+#echo DX_FLAG_dot=$DX_FLAG_dot
+#echo DX_FLAG_man=$DX_FLAG_man
+#echo DX_FLAG_html=$DX_FLAG_html
+#echo DX_FLAG_chm=$DX_FLAG_chm
+#echo DX_FLAG_chi=$DX_FLAG_chi
+#echo DX_FLAG_rtf=$DX_FLAG_rtf
+#echo DX_FLAG_xml=$DX_FLAG_xml
+#echo DX_FLAG_pdf=$DX_FLAG_pdf
+#echo DX_FLAG_ps=$DX_FLAG_ps
+#echo DX_ENV=$DX_ENV
+])
diff --git a/src/runtime/c/m4/c_ext.m4 b/src/runtime/c/m4/c_ext.m4
new file mode 100644
index 000000000..7c35c7dc3
--- /dev/null
+++ b/src/runtime/c/m4/c_ext.m4
@@ -0,0 +1,89 @@
+# AC_C_ALIGNOF
+# ------------
+# Check whether the C compiler supports the alignof(type) operator
+AC_DEFUN([AC_C_ALIGNOF],
+[
+  AC_CACHE_CHECK([for alignof],ac_cv_c_alignof,
+    [ac_cv_c_alignof=no
+     for ac_kw in alignof __alignof __alignof__; do
+       AC_COMPILE_IFELSE(
+	 [AC_LANG_PROGRAM([], [int align = $ac_kw (int);])],
+	 [ac_cv_c_alignof=$ac_kw; break])
+     done])
+  if test $ac_cv_c_alignof != no; then
+    AC_DEFINE([HAVE_ALIGNOF], 1,
+      [Define to 1 if alignof works on your compiler])
+    if test $ac_cv_c_alignof != alignof; then
+      AC_DEFINE_UNQUOTED([alignof], [$ac_cv_c_alignof],
+	[Define to the name of the alignof operator.])
+    fi
+  fi
+])
+
+# AC_C_FAM_IN_MEM
+# ---------------
+# Check whether the C compiler supports a flexible array member
+# in a struct that is the (last) member of a struct
+AC_DEFUN([AC_C_FAM_IN_MEM],
+[
+  AC_CACHE_CHECK([for flexible array members in struct members],
+    ac_cv_c_fam_in_mem,
+    [AC_COMPILE_IFELSE(
+      [AC_LANG_PROGRAM([
+	struct { struct { char foo[]; } bar; } baz;
+      ])], 
+      [ac_cv_c_fam_in_mem=yes],
+      [ac_cv_c_fam_in_mem=no])])
+  if test $ac_cv_c_fam_in_mem = yes; then
+    AC_DEFINE([CAN_HAVE_FAM_IN_MEMBER], 1,
+    [Define to 1 if a struct with flexible array members can be 
+     the last member of another struct.])
+  fi
+])
+
+
+## AC_C_STATEMENT_EXPRESSIONS
+AC_DEFUN([AC_C_STATEMENT_EXPRESSIONS],
+[
+  AC_CACHE_CHECK([for statement expressions],
+    ac_cv_c_statement_expressions,
+    [AC_COMPILE_IFELSE(
+      [AC_LANG_PROGRAM([], [int x = ({ int a = 42; a = a + 1; a; })])],
+      [ac_cv_c_statement_expressions=yes],
+      [ac_cv_c_statement_expressions=no])])
+  if test $ac_cv_c_statement_expressions = yes; then
+    AC_DEFINE([HAVE_STATEMENT_EXPRESSIONS], 1,
+    [Define to 1 if statement expressions are supported.])
+  fi
+])
+
+## AC_C_ASCII
+AC_DEFUN([AC_C_ASCII],
+[
+  AC_CACHE_CHECK([whether the execution character set uses ASCII],
+    ac_cv_c_ascii,
+    [AC_RUN_IFELSE(
+      [AC_LANG_PROGRAM([], [[
+
+int i;
+static const char ascii[128] =
+	"\0\0\0\0\0\0\0\a\b\t\n\v\f\r\0\0"
+	"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
+	" !\"#\0%&'()*+,-./0123456789:;<=>?"
+	"\0ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\\\]^_"
+	"\0abcdefghijklmnopqrstuvwxyz{|}~\0";
+
+for (i = 0; i < 128; i++) {
+  if (ascii[i] && ascii[i] != (char) i) {
+    return 1;
+  }
+}
+
+]])],
+      [ac_cv_c_ascii=yes],
+      [ac_cv_c_ascii=no])])
+  if test $ac_cv_c_ascii = yes; then
+    AC_DEFINE([CHAR_ASCII], 1,
+    [Define to 1 if the encoding of the basic character set is ASCII.])
+  fi
+])