#!/bin/sh

cd $(dirname "$0") || exit 1
. 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/oblibs]
  --includedir=DIR              include files for the C compiler [PREFIX/include]

 If no --prefix option is given, by default libdir (but not dynlibdir)
 will be /usr/lib/oblibs, and includedir will be /usr/include.

Dependencies:
  --with-sysdeps=DIR            use sysdeps in DIR [PREFIX/lib/skalibs/sysdeps]
  --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

 If no --prefix option is given, by default sysdeps will be fetched from
 /usr/lib/skalibs/sysdeps.

Optional features:
  --disable-shared              do not build shared libraries [disabled]
  --disable-static              do not build static libraries [disabled]
  --disable-allstatic           do not prefer linking against static libraries [enabled]
  --disable-all-pic             do not build static libraries as PIC [enabled]

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
}

# Actual script

CC_AUTO=
CPPFLAGS_AUTO="-D_POSIX_C_SOURCE=200809L -D_XOPEN_SOURCE=700 -Isrc/include"
CPPFLAGS_POST="$CPPFLAGS"
CPPFLAGS=
CFLAGS_AUTO="-pipe -Wall"
CFLAGS_POST="$CFLAGS"
CFLAGS="-O2"
LDFLAGS_AUTO=
LDFLAGS_POST="$LDFLAGS"
LDFLAGS=
LDFLAGS_NOSHARED=
LDFLAGS_SHARED=-shared
prefix=
dynlibdir='$prefix/lib'
libdir='$prefix/lib/$package'
includedir='$prefix/include'
sysdeps='$prefix/lib/skalibs/sysdeps'
manualsysdeps=false
shared=true
static=false
allpic=false
home=
allstatic=false
evenmorestatic=false
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#*=} ;;
    --with-sysdeps=*) sysdeps=${arg#*=} manualsysdeps=true ;;
    --with-include=*) var=${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 $var" ;;
    --enable-shared|--enable-shared=yes) shared=true ;;
    --disable-shared|--enable-shared=no) shared=false ;;
    --enable-static|--enable-static=yes) static=true ;;
    --disable-static|--enable-static=no) static=false ;;
    --enable-allstatic|--enable-allstatic=yes) allstatic=true ;;
    --disable-allstatic|--enable-allstatic=no) allstatic=false ; evenmorestatic=false ;;
    --enable-all-pic|--enable-all-pic=yes) allpic=true ;;
    --disable-all-pic|--enable-all-pic=no) allpic=false ;;
    --enable-*|--disable-*|--with-*|--without-*|--*dir=*) ;;
    --host=*|--target=*) target=${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" = '$prefix/include' ; then
    includedir=/usr/include
  fi
  if test "$sysdeps" = '$prefix/lib/skalibs/sysdeps' ; then
    sysdeps=/usr/lib/skalibs/sysdeps
  fi
fi

# Expand installation directories
stripdir prefix
for i in exec_prefix dynlibdir libdir includedir sysdeps ; 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

# 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 ${CC}
if test -n "$CC_AUTO" ; then
  b=`basename "$CC"`
  adjust_cross=false
  if test "$b" != "$CC" ; then
    adjust_cross=true
    echo "$0: warning: compiler $CC is declared with its own path. If it's not accessible via PATH, you will need to pass AR, RANLIB and STRIP make variables to the make invocation." 1>&2
  fi
  if test -n "$cross" ; then
    if test "$b" = "${b##$cross}" ; then
      echo "$0: warning: compiler $CC is declared as a cross-compiler for target $target but does not start with prefix ${cross}" 1>&2
    elif $adjust_cross ; then
      cross=`dirname "$CC"`/"$cross"
    fi
  fi
fi
trycc ${cross}gcc
trycc ${cross}clang
trycc ${cross}cc
test -n "$CC_AUTO" || fail "$0: cannot find a C compiler"
echo "  ... $CC_AUTO"
echo "Checking whether C compiler works... "
echo "typedef int x;" > "$tmpc"
if $CC_AUTO $CPPFLAGS_AUTO $CPPFLAGS $CPPFLAGS_POST $CFLAGS_AUTO $CFLAGS $CFLAGS_POST -c -o /dev/null "$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"

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

spawn_lib=$(cat $sysdeps/spawn.lib)
socket_lib=$(cat $sysdeps/socket.lib)
sysclock_lib=$(cat $sysdeps/sysclock.lib)
timer_lib=$(cat $sysdeps/timer.lib)
util_lib=$(cat $sysdeps/util.lib)

if $allpic ; then
  tryflag CPPFLAGS_AUTO -fPIC
fi

tryflag CFLAGS_AUTO -std=c99
tryflag CFLAGS -fomit-frame-pointer
tryflag CFLAGS_AUTO -fno-exceptions
tryflag CFLAGS_AUTO -fno-unwind-tables
tryflag CFLAGS_AUTO -fno-asynchronous-unwind-tables
tryflag CFLAGS -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
tryldflag LDFLAGS_SHARED -nostartfiles
tryldflag LDFLAGS_AUTO -Wl,--as-needed
tryflag CFLAGS_AUTO -ffunction-sections
tryflag CFLAGS_AUTO -fdata-sections

tryldflag LDFLAGS_AUTO -Wl,--sort-section=alignment
tryldflag LDFLAGS_AUTO -Wl,--sort-common

if $evenmorestatic ; then
  LDFLAGS_NOSHARED=-static
fi

if $shared ; then
  tryldflag LDFLAGS -Wl,--hash-style=both
fi

LDFLAGS_SHARED="${LDFLAGS_SHARED}${addlibdpath}"

if $allstatic ; then
  LDFLAGS_NOSHARED="${LDFLAGS_NOSHARED}${addlibspath}"
  tryldflag LDFLAGS_NOSHARED -Wl,--gc-sections
else
  LDFLAGS_NOSHARED="${LDFLAGS_NOSHARED}${addlibdpath}"
fi

rm -f "$tmps"
echo "Creating config.mak..."
cmdline=$(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
dynlibdir := $dynlibdir
libdir := $libdir
includedir := $includedir
sysdeps := $sysdeps
version := $version
home := $home

SPAWN_LIB := ${spawn_lib}
SOCKET_LIB := ${socket_lib}
SYSCLOCK_LIB := ${sysclock_lib}
TIMER_LIB := ${timer_lib}
UTIL_LIB := ${util_lib}

CC := ${CC_AUTO}
CPPFLAGS_AUTO := $CPPFLAGS_AUTO
CPPFLAGS := $CPPFLAGS $CPPFLAGS_POST
CFLAGS_AUTO := $CFLAGS_AUTO
CFLAGS := $CFLAGS $CFLAGS_POST
LDFLAGS_AUTO := $LDFLAGS_AUTO
LDFLAGS := $LDFLAGS $LDFLAGS_POST
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 := liboblibs.a.xyzzy"
else
  echo "STATIC_LIBS :="
fi
if $shared ; then
  echo "SHARED_LIBS := liboblibs.so.xyzzy"
else
  echo "SHARED_LIBS :="
fi
if $allpic ; then
  echo "STATIC_LIBS_ARE_PIC := 1"
else
  echo "STATIC_LIBS_ARE_PIC :="
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 ${package_macro_name}_HOME "$home"
EOF

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