#!/bin/sh

. package/info

usage () {
  cat <<EOF
Usage: $0 [OPTION]... [TARGET]

Defaults for the options are specified in brackets.

System types:
  --target=TARGET               configure to run on target TARGET [detected]
  --host=TARGET                 same as --target

Installation directories:
  --prefix=PREFIX               main installation prefix [/]

Fine tuning of the installation directories:
  --dynlibdir=DIR               shared library files [PREFIX/lib]
  --libdir=DIR                  static library files [PREFIX/lib/$package]
  --includedir=DIR              include files for the C compiler [PREFIX/include]
  --datadir=DIR                 global configuration files [PREFIX/etc]
  --sysdepdir=DIR               sysdeps directory [PREFIX/lib/$package/sysdeps]

 If no --prefix option is given, by default libdir will be /usr/lib/$package,
 includedir will be /usr/include and sysdepdir will be /usr/lib/$package/sysdeps.

Dependencies:
  --with-sysdeps=DIR            use provided sysdeps in DIR [autodetected]
  --with-include=DIR            add DIR to the list of searched directories for headers
  --with-lib=DIR                add DIR to the list of searched directories for static libraries
  --with-dynlib=DIR             add DIR to the list of searched directories for shared libraries

Optional features:
  --disable-shared              do not build shared libraries [enabled]
  --disable-static              do not build static libraries [enabled]
  --enable-slashpackage[=ROOT]  assume /package installation at ROOT [disabled]

$package options:
  --disable-ipv6                do not build IPv6 support [enabled]
  --enable-iopause-select       prefer select() over poll() for iopause implementation [disabled]
  --enable-tai-clock            assume the system clock is TAI-10 instead of UTC [disabled]
  --enable-clock                use clock_gettime() instead of gettimeofday() [disabled]
  --enable-monotonic            count time with CLOCK_MONOTONIC instead of CLOCK_REALTIME
  --with-default-path=PATH      default executable search path [/usr/bin:/bin]

EOF
  exit 0
}

# Helper functions

# If your system does not have printf, you can comment this, but it is
# generally not a good idea to use echo.
# See http://www.etalabs.net/sh_tricks.html
echo () {
  IFS=" "
  printf %s\\n "$*"
}

quote () {
  tr '\n' ' ' <<EOF | grep '^[-[:alnum:]_=,./:]* $' >/dev/null 2>&1 && { echo "$1" ; return 0 ; }
$1
EOF
  echo "$1" | sed -e "s/'/'\\\\''/g" -e "1s/^/'/" -e "\$s/\$/'/" -e "s#^'\([-[:alnum:]_,./:]*\)=\(.*\)\$#\1='\2#" -e "s|\*/|* /|g"
}

fail () {
  echo "$*"
  exit 1
}

fnmatch () {
  eval "case \"\$2\" in $1) return 0 ;; *) return 1 ;; esac"
}

cmdexists () {
  type "$1" >/dev/null 2>&1
}

trycc () {
  test -z "$CC_AUTO" && cmdexists "$1" && CC_AUTO="$*"
}

stripdir () {
  while eval "fnmatch '*/' \"\${$1}\"" ; do
    eval "$1=\${$1%/}"
  done
}

tryflag () {
  echo "Checking whether compiler accepts $2 ..."
  echo "typedef int x;" > "$tmpc"
  if $CC_AUTO "$2" -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
    echo "  ... yes"
    eval "$1=\"\${$1} \$2\""
    eval "$1=\${$1# }"
    return 0
  else
    echo "  ... no"
    return 1
  fi
}

tryldflag () {
  echo "Checking whether linker accepts $2 ..."
  echo "typedef int x;" > "$tmpc"
  if $CC_AUTO -nostdlib "$2" -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
    echo "  ... yes"
    eval "$1=\"\${$1} \$2\""
    eval "$1=\${$1# }"
    return 0
  else
    echo "  ... no"
    return 1
  fi
}

choose () {
  what="$1"
  name="$2"
  macro="$3"
  echo "Checking whether system has $4..."
  shift 4
  libs="$*"
  r=true
  case "$what" in
    *c*) $CC_AUTO $CPPFLAGS_AUTO $CFLAGS_AUTO -o try$name.o -c src/sysdeps/try$name.c 2>/dev/null || r=false ;;
  esac
  if $r ; then
    case "$what" in
      *l*) $CC_AUTO $CFLAGS_AUTO $LDFLAGS_AUTO -o try$name try$name.o $libs 2>/dev/null || r=false ;;
    esac
  fi
  if $r ; then
    case "$what" in
     *r*) ./try$name >/dev/null 2>&1 ; r=$?
          case "$r" in
           111) echo "  ... test crashed, aborting." ; exit 111 ;;
           0) r=true ;;
           *) r=false ;;
          esac
    esac
  fi
  rm -f try$name.o try$name
  if $r ; then
    echo "$name: yes" >> $sysdeps/sysdeps
    echo "#define ${package_macro_name}_HAS$macro" >> $sysdeps/sysdeps.h
    echo "  ... yes"
  else
    echo "$name: no" >> $sysdeps/sysdeps
    echo "#undef ${package_macro_name}_HAS$macro" >> $sysdeps/sysdeps.h
    echo "  ... no"
  fi
}

trytypes () {
  echo "Checking size and signedness of standard types..."
  $CC_AUTO $CPPFLAGS_AUTO $CFLAGS_AUTO $LDFLAGS_AUTO -o output-types src/sysdeps/output-types.c
  ./output-types >> $sysdeps/sysdeps
  ./output-types | grep -F sizeof | while read key value ; do
    caps=$(echo $key | sed s/:\$// | tr a-z A-Z)
    echo "#define ${package_macro_name}_${caps} $value" >> $sysdeps/sysdeps.h
  done
  ./output-types | grep -F signed | while read key value ; do
    caps=$(echo $key | sed s/:\$// | tr a-z A-Z)
    if test $value = yes ; then
      echo "#define ${package_macro_name}_HASSIGNED${caps}"
      echo "#undef ${package_macro_name}_HASUNSIGNED${caps}"
    else
      echo "#undef ${package_macro_name}_HASSIGNED${caps}"
      echo "#define ${package_macro_name}_HASUNSIGNED${caps}"
    fi >> $sysdeps/sysdeps.h
  done
  rm -f output-types
  echo "  ... done"
}

trylibs () {
  args=
  name=$1
  echo "Checking whether system has $2..." >&3
  shift 2
  if $CC_AUTO $CPPFLAGS_AUTO $CFLAGS_AUTO -c -o try$name.o src/sysdeps/try$name.c 2>/dev/null ; then
    until $CC_AUTO $CFLAGS_AUTO $LDFLAGS_AUTO -o /dev/null try$name.o $args 2>/dev/null ; do
      if test -z "$*" ; then
        rm -f try$name.o
        echo
        echo "  ... no" >&3
        return 1
      fi
      args="$args $1"
      shift
    done
    echo ${args# }
    if test -z "$args" ; then
      echo "  ... yes" >&3
    else
      echo "  ... yes, with$args" >&3
    fi
    rm -f try$name.o
    return 0
  else
    echo
    echo "  ... no" >&3
    return 1
  fi
}

# Actual script

CC_AUTO=
CFLAGS_AUTO="$CFLAGS"
CPPFLAGS_AUTO="-D_POSIX_C_SOURCE=200809L -D_XOPEN_SOURCE=700 -O2 $CPPFLAGS"
LDFLAGS_AUTO="$LDFLAGS"
LDFLAGS_NOSHARED=
LDFLAGS_SHARED=-shared
prefix=
dynlibdir='$prefix/lib'
libdir='$prefix/lib/$package'
includedir='$prefix/include'
datadir='$prefix/etc'
sysdepdir='$prefix/lib/$package/sysdeps'
sysdeps=
shared=true
static=true
slashpackage=false
ipv6=true
select=false
taiclock=false
clockrt=false
clockmon=false
ddefaultpath=/usr/bin:/bin
defaultpath=$ddefaultpath
dpathorig=true
sproot=
home=
exthome=
addincpath=''
addlibspath=''
addlibdpath=''
vpaths=''
vpathd=''
build=


for arg ; do
  case "$arg" in
    --help) usage ;;
    --prefix=*) prefix=${arg#*=} ;;
    --dynlibdir=*) dynlibdir=${arg#*=} ;;
    --libdir=*) libdir=${arg#*=} ;;
    --includedir=*) includedir=${arg#*=} ;;
    --datadir=*) datadir=${arg#*=} ;;
    --sysdepdir=*) sysdepdir=${arg#*=} ;;
    --with-sysdeps=*) sysdeps=${arg#*=} ;;
    --with-include=*) var=${arg#*=} ; stripdir var ; addincpath="$addincpath -I$var" ;;
    --with-lib=*) var=${arg#*=} ; stripdir var ; addlibspath="$addlibspath -L$var" ; vpaths="$vpaths $var" ;;
    --with-dynlib=*) var=${arg#*=} ; stripdir var ; addlibdpath="$addlibdpath -L$var" ; vpathd="$vpathd $var" ;;
    --enable-shared|--enable-shared=yes) shared=true ;;
    --disable-shared|--enable-shared=no) shared=false ;;
    --enable-static|--enable-static=yes) static=true ;;
    --disable-static|--enable-static=no) static=false ;;
    --enable-slashpackage=*) sproot=${arg#*=} ; slashpackage=true ; ;;
    --enable-slashpackage) sproot= ; slashpackage=true ;;
    --disable-slashpackage) sproot= ; slashpackage=false ;;
    --enable-ipv6|--enable-ipv6=yes) ipv6=true ;;
    --disable-ipv6|--enable-ipv6=no) ipv6=false ;;
    --enable-iopause-select|--enable-iopause-select=yes) select=true ;;
    --disable-iopause-select|--enable-iopause-select=no) select=false ;;
    --enable-tai-clock|--enable-tai-clock=yes) taiclock=true ;;
    --disable-tai-clock|--enable-tai-clock=no) taiclock=false ;;
    --enable-clock|--enable-clock=yes) clockrt=true ;;
    --disable-clock|--enable-clock=no) clockrt=false ;;
    --enable-monotonic|--enable-monotonic=yes) clockmon=true ;;
    --disable-monotonic|--enable-monotonic=no) clockmon=false ;;
    --with-default-path=*) defaultpath=${arg#*=} ; dpathorig=false ;;
    --without-default-path) defaultpath=$ddefaultpath ; dpathorig=true ;;
    --enable-*|--disable-*|--with-*|--without-*|--*dir=*) ;;
    --host=*|--target=*) target=${arg#*=} ;;
    --build=*) build=${arg#*=} ;;
    -* ) echo "$0: unknown option $arg" ;;
    *=*) ;;
    *) target=$arg ;;
  esac
done

# Add /usr in the default default case
if test -z "$prefix" ; then
  if test "$libdir" = '$prefix/lib/$package' ; then
    libdir=/usr/lib/$package
  fi
  if test "$includedir" = '$prefix/include' ; then
    includedir=/usr/include
  fi
  if test "$sysdepdir" = '$prefix/lib/$package/sysdeps' ; then
    sysdepdir=/usr/lib/$package/sysdeps
  fi
fi

# Expand installation directories
stripdir prefix
for i in exec_prefix dynlibdir libdir includedir datadir sysdepdir sysdeps sproot ; do
  eval tmp=\${$i}
  eval $i=$tmp
  stripdir $i
done


# Get usable temp filenames
i=0
set -C
while : ; do
  i=$(($i+1))
  tmpc="./tmp-configure-$$-$PPID-$i.c"
  tmpe="./tmp-configure-$$-$PPID-$i.tmp"
  2>|/dev/null > "$tmpc" && break
  2>|/dev/null > "$tmpe" && break
  test "$i" -gt 50 && fail "$0: cannot create temporary files"
done
set +C
trap 'rm -f "$tmpc" "$tmpe"' EXIT ABRT INT QUIT TERM HUP

# Set slashpackage values
if $slashpackage ; then
  home=${sproot}/package/${category}/${package}-${version}
  exthome=${sproot}/package/${category}/${package}
  sysdepdir=${home}/sysdeps
  binprefix=${home}/command
  extbinprefix=${exthome}/command
  dynlibdir=${home}/library.so
  libdir=${home}/library
  includedir=${home}/include
  if $dpathorig ; then
    if echo $defaultpath | tr : '\n' | grep -q '^/command$' ; then : ; else
      defaultpath="/command:$defaultpath"
    fi
  fi
fi

# Find a C compiler to use
if test -n "$target" && test x${build} != x${target} ; then
  cross=${target}-
else
  cross=
fi
echo "Checking for C compiler..."
trycc ${cross}${CC}
trycc ${cross}gcc
trycc ${cross}clang
trycc ${cross}cc
test -n "$CC_AUTO" || { echo "$0: cannot find a C compiler" ; exit 1 ; }
echo "  ... $CC_AUTO"
echo "Checking whether C compiler works... "
echo "typedef int x;" > "$tmpc"
if $CC_AUTO $CPPFLAGS_AUTO $CFLAGS_AUTO -c -o /dev/null "$tmpc" 2>"$tmpe" ; then
  echo "  ... yes"
else
  echo "  ... no. Compiler output follows:"
  cat < "$tmpe"
  exit 1
fi

echo "Checking target system type..."
if test -z "$target" ; then
  if test -n "$build" ; then
    target=$build ;
  else
    target=$($CC_AUTO -dumpmachine 2>/dev/null) || target=unknown
  fi
fi
echo "  ... $target"

tryflag CPPFLAGS_AUTO -std=c99
tryflag CPPFLAGS_AUTO -fomit-frame-pointer
tryflag CPPFLAGS_AUTO -fno-exceptions
tryflag CPPFLAGS_AUTO -fno-unwind-tables
tryflag CPPFLAGS_AUTO -fno-asynchronous-unwind-tables
tryflag CPPFLAGS_AUTO -Wa,--noexecstack
tryflag CPPFLAGS_AUTO -fno-stack-protector
tryflag CPPFLAGS_AUTO -Werror=implicit-function-declaration
tryflag CPPFLAGS_AUTO -Werror=implicit-int
tryflag CPPFLAGS_AUTO -Werror=pointer-sign
tryflag CPPFLAGS_AUTO -Werror=pointer-arith
tryflag CPPFLAGS_AUTO -Wno-unused-value
tryflag CPPFLAGS_AUTO -Wno-parentheses
tryflag CFLAGS_AUTO -ffunction-sections
tryflag CFLAGS_AUTO -fdata-sections

tryldflag LDFLAGS_AUTO -Wl,--sort-section=alignment
tryldflag LDFLAGS_AUTO -Wl,--sort-common
if $shared ; then
  tryldflag LDFLAGS_AUTO -Wl,--hash-style=both
fi

if test -n "$sysdeps" ; then
  if test ! -d $sysdeps || test ! -f $sysdeps/target ; then
    echo "$0: error: $sysdeps is not a valid sysdeps directory"
    exit 1
  fi
  if [ "x$target" != "x$(cat $sysdeps/target)" ] ; then
    echo "$0: error: target $target does not match the contents of $sysdeps/target"
    exit 1
  fi
  echo "Using pre-computed sysdeps in $sysdeps."
  spawn_lib=$(cat $sysdeps/spawn.lib)
  socket_lib=$(cat $sysdeps/socket.lib)
  sysclock_lib=$(cat $sysdeps/sysclock.lib)
  tainnow_lib=$(cat $sysdeps/tainnow.lib)
  timer_lib=$(cat $sysdeps/timer.lib)
  util_lib=$(cat $sysdeps/util.lib)
else
  sysdeps=sysdeps.cfg
  mkdir -p $sysdeps
  echo "$target" > $sysdeps/target
  echo "target: $target" > $sysdeps/sysdeps
  cat <<EOF > $sysdeps/sysdeps.h
/* ISC license. */

#ifndef SYSDEPS_H
#define SYSDEPS_H

#define SKALIBS_TARGET "$target"
EOF

  exec 3>&1
  util_lib=
  echo > $sysdeps/util.lib

  socket_lib=`trylibs lsock 'accessible socket functions' -lsocket -lnsl` || fail "$0: unable to determine socket.lib sysdep"
  echo "$socket_lib" > $sysdeps/socket.lib

  hasclock=true
  sysclock_lib=`trylibs clockrt 'clock_gettime()' -lrt` || hasclock=false
  if $clockrt ; then
    tainnow_lib=$sysclock_lib
  else
    tainnow_lib=
  fi
  echo "$sysclock_lib" > $sysdeps/sysclock.lib
  echo "$tainnow_lib" > $sysdeps/tainnow.lib
  if $hasclock ; then
    echo 'clockrt: yes' >> $sysdeps/sysdeps
    echo "#define ${package_macro_name}_HASCLOCKRT" >> $sysdeps/sysdeps.h
    choose cl clockmon CLOCKMON CLOCK_MONOTONIC $sysclock_lib
  else
    echo 'clockrt: no' >> $sysdeps/sysdeps
    echo "#undef ${package_macro_name}_HASCLOCKRT" >> $sysdeps/sysdeps.h
  fi

  hasspawn=true
  spawn_lib=`trylibs posixspawn 'posix_spawn()' -lrt` || hasspawn=false
  echo "$spawn_lib" > $sysdeps/spawn.lib
  if $hasspawn ; then
    echo 'posixspawn: yes' >> $sysdeps/sysdeps
    echo "#define ${package_macro_name}_HASPOSIXSPAWN" >> $sysdeps/sysdeps.h
  else
    echo 'posixspawn: no' >> $sysdeps/sysdeps
    echo "#undef ${package_macro_name}_HASPOSIXSPAWN" >> $sysdeps/sysdeps.h
  fi

  hastimer=true
  timer_lib=`trylibs timer 'timer_create()' -lrt` || hastimer=false
  echo "$timer_lib" > $sysdeps/timer.lib
  if $hastimer ; then
    echo 'timer: yes' >> $sysdeps/sysdeps
    echo "#define ${package_macro_name}_HASTIMER" >> $sysdeps/sysdeps.h
  else
    echo 'timer: no' >> $sysdeps/sysdeps
    echo "#undef ${package_macro_name}_HASTIMER" >> $sysdeps/sysdeps.h
  fi
  exec 3>&-

  echo "Checking system endianness..."
  $CC_AUTO $CPPFLAGS_AUTO $CFLAGS_AUTO -o tryendianness src/sysdeps/tryendianness.c
  endianness=$(./tryendianness) || fail "$0: unable to determine endianness"
  echo "endianness: $endianness" >> $sysdeps/sysdeps
  echo "#define ${package_macro_name}_ENDIANNESS \"$endianness\"" >> $sysdeps/sysdeps.h
  echo "  ... $endianness"
  rm -f tryendianness

  trytypes
  choose clr accept4 ACCEPT4 'accept4()'
  choose clr ancilautoclose ANCILAUTOCLOSE 'auto-close after fd-passing'
  choose c cmsgcloexec CMSGCLOEXEC 'MSG_CMSG_CLOEXEC'
  choose clr devurandom DEVURANDOM '/dev/urandom'
  choose c eproto EPROTO EPROTO
  choose cl eventfd EVENTFD 'eventfd()'
  choose cl flock FLOCK 'flock()'
  choose cl getpeereid GETPEEREID 'getpeereid()'
  choose cl sopeercred SOPEERCRED 'SO_PEERCRED'
  choose cl getpeerucred GETPEERUCRED 'getpeerucred()'
  choose cl ipv6 IPV6 'IPv6 support' $socket_lib
  choose clr malloc0 MALLOC0 'non-NULL malloc(0)'
  choose c msgdontwait MSGDONTWAIT 'MSG_DONTWAIT'
  choose clr nbwaitall NBWAITALL 'non-blocking MSG_WAITALL'
  choose cl openat OPENAT 'openat()'
  choose cl linkat LINKAT 'linkat()'
  choose clr pipe2 PIPE2 'pipe2()'
  choose clr ppoll PPOLL 'ppoll()'
  choose cl revoke REVOKE 'revoke()'
  choose cl sendfile SENDFILE 'sendfile()'
  choose cl setgroups SETGROUPS 'setgroups()'
  choose cl settimeofday SETTIMEOFDAY 'settimeofday()'
  choose clr signalfd SIGNALFD 'signalfd()'
  choose clr splice SPLICE 'splice()'
  choose cl strcasestr STRCASESTR 'strcasestr()'
  choose cl strnlen STRNLEN 'strnlen()'
  choose c uint64t UINT64T 'uint64_t'
  choose cl futimens FUTIMENS 'futimens()'
  choose cl futimes FUTIMES 'futimes()'
  choose cl arc4random ARC4RANDOM 'arc4random()'
  choose cl arc4random_addrandom ARC4RANDOM_ADDRANDOM 'arc4random_addrandom()'
  choose clr getrandom GETRANDOM 'getrandom()'
  choose cl itimer ITIMER 'setitimer()'

  echo '#endif' >> $sysdeps/sysdeps.h
fi

echo "Copying $sysdeps/sysdeps.h to src/include/${package}/sysdeps.h ..."
cat < $sysdeps/sysdeps.h > src/include/${package}/sysdeps.h
echo "  ... done"

echo "Creating config.mak..."
cmdline=$(quote "$0")
for i ; do cmdline="$cmdline $(quote "$i")" ; done
exec 3>&1 1>config.mak
cat << EOF
# This file was generated by:
# $cmdline
# Any changes made here will be lost if configure is re-run.

target := $target
package := $package
prefix := $prefix
datadir := $datadir
sysdepdir := $sysdepdir
dynlibdir := $dynlibdir
libdir := $libdir
includedir := $includedir
sysdeps := $sysdeps
version := $version
sproot := $sproot
home := $home
exthome := ${exthome}
ipv6 := ${ipv6}
SPAWN_LIB := ${spawn_lib}
SOCKET_LIB := ${socket_lib}
SYSCLOCK_LIB := ${sysclock_lib}
TAINNOW_LIB := ${tainnow_lib}
TIMER_LIB := ${timer_lib}
UTIL_LIB := ${util_lib}
CC := ${CC_AUTO##${cross}}
CFLAGS := $CFLAGS_AUTO
CPPFLAGS := $CPPFLAGS_AUTO
LDFLAGS := $LDFLAGS_AUTO
LDFLAGS_NOSHARED := $LDFLAGS_NOSHARED
LDFLAGS_SHARED := $LDFLAGS_SHARED
CROSS_COMPILE := ${cross}
EOF
if test -n "$vpaths" ; then
  echo "vpath lib%a$vpaths"
fi
if test -n "$vpathd" ; then
  echo "vpath lib%.so$vpathd"
fi

if $static ; then
  echo "STATIC_LIBS := libskarnet.a.xyzzy"
else
  echo "STATIC_LIBS :="
fi
if $shared ; then
  echo "SHARED_LIBS := libskarnet.so.xyzzy"
else
  echo "SHARED_LIBS :="
fi

exec 1>&3 3>&-
echo "  ... done."

echo "Creating src/include/${package}/config.h..."
mkdir -p -m 0755 src/include/${package}
exec 3>&1 1> src/include/${package}/config.h
cat <<EOF
/* ISC license. */

/* Generated by: $cmdline */

#ifndef ${package_macro_name}_CONFIG_H
#define ${package_macro_name}_CONFIG_H

#define ${package_macro_name}_VERSION "$version"
#define ${package_macro_name}_DEFAULTPATH "$defaultpath"
#define ${package_macro_name}_ETC "$datadir"
#define ${package_macro_name}_SPROOT "$sproot"
#define ${package_macro_name}_HOME "$home"
EOF
if $taiclock ; then
  echo "#define ${package_macro_name}_FLAG_CLOCKISTAI"
else
  echo "#undef ${package_macro_name}_FLAG_CLOCKISTAI"
fi
if $clockrt ; then
  echo "#define ${package_macro_name}_FLAG_USERT"
else
  echo "#undef ${package_macro_name}_FLAG_USERT"
fi
if $clockmon ; then
  echo "#define ${package_macro_name}_FLAG_USEMON"
else
  echo "#undef ${package_macro_name}_FLAG_USEMON"
fi
if $ipv6 ; then
  echo "#define ${package_macro_name}_FLAG_WANTIPV6"
else
  echo "#undef ${package_macro_name}_FLAG_WANTIPV6"
fi
if $select ; then
  echo "#define ${package_macro_name}_FLAG_PREFERSELECT"
else
  echo "#undef ${package_macro_name}_FLAG_PREFERSELECT"
fi

echo
echo "#endif"
exec 1>&3 3>&-
echo "  ... done."