dnl -*-autoconf-*-
dnl
dnl Configuration script for Catacomb
dnl
dnl (c) 2013 Straylight/Edgeware
dnl

dnl----- Licensing notice ---------------------------------------------------
dnl
dnl This file is part of Catacomb.
dnl
dnl Catacomb is free software; you can redistribute it and/or modify
dnl it under the terms of the GNU Library General Public License as
dnl published by the Free Software Foundation; either version 2 of the
dnl License, or (at your option) any later version.
dnl
dnl Catacomb is distributed in the hope that it will be useful,
dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
dnl GNU Library General Public License for more details.
dnl
dnl You should have received a copy of the GNU Library General Public
dnl License along with Catacomb; if not, write to the Free
dnl Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
dnl MA 02111-1307, USA.

dnl--------------------------------------------------------------------------
dnl Initialization.

mdw_AUTO_VERSION
AC_INIT([catacomb], AUTO_VERSION, [mdw@distorted.org.uk])
AC_CONFIG_SRCDIR([catacomb.pc.in])
AC_CONFIG_AUX_DIR([config])
AM_INIT_AUTOMAKE([foreign parallel-tests color-tests subdir-objects])
AC_CANONICAL_HOST
mdw_SILENT_RULES

AC_PROG_CC
AX_CFLAGS_WARN_ALL
AM_PROG_LIBTOOL
mdw_LIBTOOL_VERSION_INFO

AM_PROG_AS

AC_PROG_YACC

AC_SUBST(AM_CFLAGS)

dnl--------------------------------------------------------------------------
dnl Define language support for assembler.
dnl
dnl This is stolen from https://gitlab.crest.iu.edu/jsfiroz/hpx/commit/
dnl 84be4345db6eec3797a57b8e53483cb43f4733bf

AC_LANG_DEFINE([CPPAS], [cppas], [CPPAS], [CCAS], [C],
  [ac_ext=S ac_cpp='$CPP $CPPFLAGS'
   ac_compile='$CCAS -c $CCASFLAGS $CPPFLAGS dnl
	conftest.$ac_ext >&AS_MESSAGE_LOG_FD'
   ac_link='$CCAS -oconftest$ac_exeext $CCASFLAGS $CPPFLAGS $LDFLAGS dnl
	conftest.$ac_ext $LIBS >&AS_MESSAGE_LOG_FD'])

AC_DEFUN([AC_LANG_PREPROC(CPPAS)], [AC_REQUIRE([AC_PROG_CPP])])
AC_DEFUN([AC_LANG_COMPILER(CPPAS)], [AC_REQUIRE([AM_PROG_AS])])
AC_DEFUN([AC_LANG_CONFTEST(CPPAS)],
  [cat confdefs.h - <<_ACEOF >conftest.$ac_ext
/* end confdefs.h. */
$1
_ACEOF])

dnl--------------------------------------------------------------------------
dnl Host-specific configuration.

dnl The table of CPU families and ABIs which we might support.  Support is
dnl not uniform: each dispatched function might or might not have an
dnl implementation for any particular CPU/ABI combination.
AC_DEFUN([catacomb_CPU_FAMILIES],
  [$1([i[[3-6]]86,cygwin], [x86], [win])
   $1([i[[3-6]]86,*], [x86], [sysv])
   $1([x86_64,cygwin], [amd64], [win])
   $1([x86_64,*], [amd64], [sysv])
   $1([arm,* | armv*,*], [armel], [std])
   $1([aarch64,*], [arm64], [std])])

dnl A utility to clear the `seen' flags, used so as to process each CPU or
dnl ABI once.
m4_define([catacomb_CLEAR_FLAGS],
[m4_ifdef([catacomb_seen_cpu/$2],
	  [m4_undefine([catacomb_seen_cpu/$2])])dnl
m4_ifdef([catacomb_seen_abi/$3],
	  [m4_undefine([catacomb_seen_abi/$3])])])

dnl Identify the current host.
case $host_cpu,$host_os in
  m4_define([catacomb_CPU_CASE],
    [$1) CPUFAM=$2 ABI=$3 ;;
])
  catacomb_CPU_FAMILIES([catacomb_CPU_CASE])
  *) CPUFAM=nil ABI=nil ;;
esac

dnl Now check the assembler.  We have target-specific requirements here, so
dnl we couldn't do this any earlier.
AC_CACHE_CHECK(
  [whether the assembler is likely to work], [mdw_cv_gnuish_as],
  [AC_LANG_PUSH([CPPAS])
   AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
	.text
	.L\$_test = 23
.macro	mymac
	.L\$_test = .L\$_test + 1
.endm
	.globl	foo
	.extern	bar
	mymac]])],
     [mdw_cv_gnuish_as=yes], [mdw_cv_gnuish_as=no])
   case $CPUFAM in
     x86 | amd64)
       AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
	.text
	.arch pentium4
	.intel_syntax noprefix
	.globl	foo
foo:
	adcd	var, 0
	ret
	.data
var:	.long	1
	]])],
	 [:], [mdw_cv_gnuish_as=no])
       ;;
   esac
   AC_LANG_POP([CPPAS])])
AM_CONDITIONAL([GNUISH_AS], [test $mdw_cv_gnuish_as = yes])
if test $mdw_cv_gnuish_as = no; then CPUFAM=nil ABI=nil; fi

dnl A hairy macro used to set the `CPUFAM_...' and `ABI_...' variables.  We
dnl basically need to do the same thing for the family and ABI, so it's worth
dnl some effort to hide the ugliness.
m4_define([catacomb_DEFINE_CPU_OR_ABI],
[case $$1 in
  m4_define([_def],
    [m4_ifdef([catacomb_seen_$3/$$2], [],
      [$$2)
	AC_DEFINE([$4]m4_translit([$$2], [a-z], [A-Z]), [1], [$5])
	;;m4_define([catacomb_seen_$3/$$2], [t])])])
  catacomb_CPU_FAMILIES([_def])
  nil) ;;
  *) AC_MSG_ERROR([BUG: unexpected $1 \`$$1']) ;;
esac])

dnl Now that's out the way, we can explain what we're doing.
AC_MSG_CHECKING([CPU family and ABI])

dnl Figure out the target CPU family and ABI.
catacomb_CPU_FAMILIES([catacomb_CLEAR_FLAGS])
catacomb_DEFINE_CPU_OR_ABI([CPUFAM], [2], [cpu],
  [CPUFAM_], [Define if target CPU is \`$][2\'.])
catacomb_DEFINE_CPU_OR_ABI([ABI], [3], [abi],
  [ABI_], [Define if target ABI is \`$][3\'.])

dnl Establish Automake conditions for things.
catacomb_CPU_FAMILIES([catacomb_CLEAR_FLAGS])
m4_define([catacomb_COND_CPU],
[m4_define([_CPU], m4_translit([$2], [a-z], [A-Z]))
m4_define([_ABI], m4_translit([$3], [a-z], [A-Z]))
AM_CONDITIONAL([CPUABI_]_CPU[_]_ABI, [test x$CPUFAM/$ABI = x$2/$3])
m4_ifdef([catacomb_seen_cpu/$2], [],
[AM_CONDITIONAL([CPUFAM_]_CPU, [test x$CPUFAM = x$2])dnl
m4_define([catacomb_seen_cpu/$2], [t])])
m4_ifdef([catacomb_seen_abi/$3], [],
[AM_CONDITIONAL([ABI_]_ABI, [test x$ABI = x$3])dnl
m4_define([catacomb_seen_abi/$3], [t])])])
catacomb_CPU_FAMILIES([catacomb_COND_CPU])
AM_CONDITIONAL([KNOWN_CPUFAM], [test x$CPUFAM != xnil])

dnl Report on what we found.
case $CPUFAM in
  nil) AC_MSG_RESULT([not supported]) ;;
  *) AC_MSG_RESULT([$CPUFAM/$ABI]) ;;
esac

dnl Consider enabling support for assembler-level debugging toys.
AC_ARG_ENABLE([asm-debug],
  AS_HELP_STRING([--enable-asm-debug],
    [enable assembler debugging features]),
  [mdw_asm_debug=$enableval], [mdw_asm_debug=no])
case $CPUFAM in nil) mdw_asm_debug=no ;; esac
case $mdw_asm_debug in
  no) ;;
  *) AC_DEFINE([ENABLE_ASM_DEBUG], [1],
       [Define to enable assembler-level debugging.]) ;;
esac
AM_CONDITIONAL([ASM_DEBUG], [test x$mdw_asm_debug != xno])

dnl Check for leading underscores on C symbols.
LT_SYS_SYMBOL_USCORE
case $sys_symbol_underscore in
  yes) AC_DEFINE([SYM_USCORE], [1],
	 [Define if C symbols are prefixed with an underscore.]) ;;
esac

dnl--------------------------------------------------------------------------
dnl CPU-specific assembler features.

AC_LANG([CPPAS])

case $CPUFAM in
  armel)
    AC_CACHE_CHECK(
      [whether the assembler understands ARMv8 crypto extensions],
      [mdw_cv_as_armv8_crypto],
      [AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
	.arch	armv8-a
	.fpu	crypto-neon-fp-armv8

	.text
	.globl	foo
foo:
	vldmia	r0, {d0-d3}
	aese.8	q0, q1
	aesmc.8	q0, q0
	vstmia	r0, {d0, d1}
	bx	r14]])],
	 [mdw_cv_as_armv8_crypto=yes],
	 [mdw_cv_as_armv8_crypto=no])])
    ;;
esac

: ${mdw_cv_as_armv8_crypto=no}
AM_CONDITIONAL([HAVE_AS_ARMV8_CRYPTO], [test $mdw_cv_as_armv8_crypto = yes])
if test $mdw_cv_as_armv8_crypto = yes; then
  AC_DEFINE([HAVE_AS_ARMV8_CRYPTO], [1],
    [Define to 1 if your ARM assembler supports the ARMv8 crypto instructions.])
fi

dnl--------------------------------------------------------------------------
dnl C programming environment.

AC_LANG([C])

CATACOMB_LIBS=

dnl Find out if we're cross-compiling.
AM_CONDITIONAL([CROSS_COMPILING], [test "$cross_compiling" = yes])

dnl Various standard types.
AC_CHECK_TYPE([pid_t], [],
  [AC_DEFINE([pid_t], [int],
     [Define to `int' if <sys/types.h> does not define])])
AC_TYPE_UID_T
AC_CHECK_TYPE([ssize_t], [],
  [AC_DEFINE([ssize_t], [int],
     [Define to `int' if <sys/types.h> does not define])])
AC_CHECK_TYPE([socklen_t], [],
  [AC_DEFINE([socklen_t], [int],
     [Define to `int' if <sys/socket.h> does not define])],
  [AC_INCLUDES_DEFAULT
#include <sys/socket.h>
])

dnl The maths library.
mdw_ORIG_LIBS=$LIBS LIBS=$CATACOMB_LIBS
AC_SEARCH_LIBS([log], [m])
AC_SEARCH_LIBS([sqrt], [m])
CATACOMB_LIBS=$LIBS LIBS=$mdw_ORIG_LIBS

dnl Logging is weird under Termux.  Unfortunately, it involves macros, so we
dnl have to do this the hard way.
AC_CACHE_CHECK(
  [library needed for syslog], [mdw_cv_syslog_lib],
  [mdw_ORIG_LIBS=$LIBS LIBS=
   for i in 0 1; do
     AC_TRY_LINK([#include <syslog.h>],
		 [openlog("test", LOG_PID, LOG_DAEMON);
		  syslog(LOG_ERR, "this is a test");],
		 [ok=t], [ok=nil])
     case $i,$ok in
       *,t) mdw_cv_syslog_lib=${LIBS:-none}; break ;;
       0,nil) LIBS="-llog" ;;
       1,nil) AC_MSG_ERROR("failed to link test program") ;;
     esac
   done
   LIBS=$mdw_ORIG_LIBS])
case $mdw_cv_syslog_lib in
  none) LOGLIBS= ;;
  *) LOGLIBS=$mdw_cv_syslog_lib ;;
esac
AC_SUBST([LOGLIBS])

dnl Find out whether very long integer types are available.
AC_CHECK_HEADERS([stdint.h])
AC_SUBST([have_stdint_h])
AX_C_LONG_LONG

dnl Some equipment wanted for checking CPU features at runtime.
AC_CHECK_HEADERS([asm/hwcap.h])
AC_CHECK_HEADERS([sys/auxv.h])
AC_CHECK_HEADERS([linux/auxvec.h])
AC_CHECK_FUNCS([getauxval])

dnl Some equipment for measuring CPU performance.
AC_CHECK_HEADERS([linux/perf_event.h])

dnl Find the bit lengths of the obvious integer types.  This will be useful
dnl when deciding on a representation for multiprecision integers.
type_bits="" type_bits_sep=""
AC_DEFUN([catacomb_UINT_BITS],
  [mdw_UINT_BITS([$2], [$1])
   type_bits="$type_bits$type_bits_sep('$1', $[]$1_bits)"
   type_bits_sep=", "])
catacomb_UINT_BITS([uchar], [unsigned char])
catacomb_UINT_BITS([ushort], [unsigned short])
catacomb_UINT_BITS([uint], [unsigned int])
catacomb_UINT_BITS([ulong], [unsigned long])
if test "$ac_cv_c_long_long" = "yes"; then
  catacomb_UINT_BITS([ullong], [unsigned long long])
fi
if test "$ac_cv_header_stdint_h" = "yes"; then
  catacomb_UINT_BITS([uintmax], [uintmax_t])
fi
AC_SUBST([type_bits])

dnl Determine the limits of common C integer types.
limits="" limits_sep=""
AC_DEFUN([catacomb_COMPILE_TIME_CONSTANT],
  [case "$2" in
     =*)
       $1="$2"; $1=${$1#=}
       ;;
     *)
       AC_CACHE_CHECK([compile-time value of $2], [mdw_cv_constant_$3],
		      [mdw_PROBE_CONSTANT([mdw_cv_constant_$3], [$2], [$4])])
       $1=$mdw_cv_constant_$3
       ;;
   esac])
AC_DEFUN([catacomb_LIMIT],
[catacomb_COMPILE_TIME_CONSTANT([lo], [$2], [$1_min],
[#include <limits.h>
#include <stddef.h>])
 catacomb_COMPILE_TIME_CONSTANT([hi], [$3], [$1_max],
[#include <limits.h>
#include <stddef.h>])
 limits="$limits$limits_sep('$1', $lo, $hi)" limits_sep=", "])
catacomb_LIMIT([SCHAR],		[SCHAR_MIN],	[SCHAR_MAX])
catacomb_LIMIT([CHAR],		[CHAR_MIN],	[CHAR_MAX])
catacomb_LIMIT([UCHAR],		[=0],		[UCHAR_MAX])
catacomb_LIMIT([UINT8],		[=0],		[=0xff])
catacomb_LIMIT([SHRT],		[SHRT_MIN],	[SHRT_MAX])
catacomb_LIMIT([USHRT],		[=0],		[USHRT_MAX])
catacomb_LIMIT([UINT16],	[=0],		[=0xffff])
catacomb_LIMIT([INT],		[INT_MIN],	[INT_MAX])
catacomb_LIMIT([UINT],		[=0],		[UINT_MAX])
catacomb_LIMIT([LONG],		[LONG_MIN],	[LONG_MAX])
catacomb_LIMIT([ULONG],		[=0],		[ULONG_MAX])
catacomb_LIMIT([UINT32],	[=0],		[=0xffffffff])
if test "$ac_cv_c_long_long" = "yes"; then
  catacomb_LIMIT([LLONG],	[LLONG_MIN],	[LLONG_MAX])
  catacomb_LIMIT([ULLONG],	[=0],		[ULLONG_MAX])
fi
catacomb_LIMIT([SIZET],		[=0],		[~(size_t)0])
AC_SUBST([limits])

dnl Figure out other aspects of the implementation's arithmetic.
AC_CACHE_CHECK([whether negative numbers use two's complement],
	[catacomb_cv_neg_twoc],
[AC_TRY_COMPILE(
[#include <limits.h>],
[int check[2*!!(-INT_MAX == INT_MIN + 1) - 1];],
[catacomb_cv_neg_twoc=yes],
[catacomb_cv_neg_twoc=no])])
case $catacomb_cv_neg_twoc in
  yes)
    AC_DEFINE([NEG_TWOC], [1],
     [Define if signed numbers are represented in two's complement.])
    ;;
esac

dnl Functions used for noise-gathering.
AC_CHECK_FUNCS([setgroups])
AC_CHECK_HEADERS([linux/random.h])
mdw_ORIG_LIBS=$LIBS LIBS=$CATACOMB_LIBS
AC_SEARCH_LIBS([clock_gettime], [rt])
CATACOMB_LIBS=$LIBS LIBS=$mdw_ORIG_LIBS
if test "$ac_cv_search_clock_gettime" != no; then
  AC_DEFINE([HAVE_CLOCK_GETTIME], [1],
	    [Define if you have the \`clock_gettime' function.])
fi
AC_CHECK_FUNCS([getentropy])
AC_CACHE_CHECK([whether the freewheel noise generator will work],
	[catacomb_cv_freewheel],
[AC_TRY_LINK(
[#include <setjmp.h>
#include <sys/time.h>],
[struct itimerval itv = { { 0, 0 }, { 0, 5000 } };
jmp_buf j;
setitimer(ITIMER_REAL, &itv, 0);
sigsetjmp(j, 1);],
[catacomb_cv_freewheel=yes],
[catacomb_cv_freewheel=no])])
case $catacomb_cv_freewheel in
  yes)
    AC_DEFINE([USE_FREEWHEEL], [1],
	      [Define if you want to use the freewheel noise generator.])
    ;;
esac

dnl Support for the passphrase pixie.
mdw_ORIG_LIBS=$LIBS
AC_SEARCH_LIBS([socket], [socket])
AC_SUBST([PIXIE_LIBS], [$LIBS])
LIBS=$mdw_ORIG_LIBS

dnl Memory locking support.
AC_CHECK_FUNCS([mlock])

dnl See if we can find Valgrind's header files.
AC_CHECK_HEADER([valgrind/memcheck.h],
  AC_DEFINE([HAVE_VALGRIND_H], [1],
	    [Define if the Valgrind header files are available.])
  [])

dnl Set the master libraries we need.
AC_SUBST([CATACOMB_LIBS])

dnl Necessary support libraries.
PKG_CHECK_MODULES([mLib], [mLib >= 2.4.1])
AM_CFLAGS="$AM_CFLAGS $mLib_CFLAGS"

dnl--------------------------------------------------------------------------
dnl Python.

dnl Make sure we have a suitable version.
AM_PATH_PYTHON([2.5])

dnl--------------------------------------------------------------------------
dnl Special debugging options.

AC_ARG_ENABLE([mpw],
  [AS_HELP_STRING([--enable-mpw], [force small-width mp digits])],
  [case "$enableval" in
    y*|t*|short)
      AC_DEFINE([FORCE_MPW_SHORT], [1],
		[Define to force small-width mp digits.])
      ;;
    cussid)
      AC_DEFINE([FORCE_MPW_CUSSID], [1],
		[Define to force strange-width mp digits.])
      ;;
   esac])

dnl--------------------------------------------------------------------------
dnl Produce output.

AC_CONFIG_HEADER([config/config.h])

AC_CONFIG_FILES(
  [Makefile]
  [base/Makefile]
  [key/Makefile]
  [math/Makefile]
  [misc/Makefile]
  [pub/Makefile]
  [rand/Makefile]
  [symm/Makefile]
  [progs/Makefile])
AC_OUTPUT

dnl----- That's all, folks --------------------------------------------------