#!/usr/bin/env sh

die() {
  printf "$1\n" >&2
  exit 1
}

usage() {
  cat <<EOF
usage: configure [options]

  --prefix=PREFIX        installation prefix [/usr]
  --exec-prefix=EPREFIX  installation prefix for executable files [PREFIX]
  --bindir=DIR           user executables [PREFIX/bin]
  --datadir=DIR          architecture-independent data files [PREFIX/share]
  --mandir=DIR           manual pages [DATADIR/man]
  --sysconfdir=DIR       directory for configuration files [/etc]

  --build=build-alias    a cpu-vendor-opsys for the system where the
                             application will be built
  --host=host-alias      a cpu-vendor-opsys for the system where the
                             application will run
  --target=target-alias  the machine that CC will produce code for

  --enable-debug         enable debugging
  --enable-static        prepare for static build

  --with-timestamp       enable timestamp support

  --without-insults      disable insults

  --uid-max=NUM          set UID_MAX (default 65535)
  --gid-max=NUM          set GID_MAX (default 65535)

  --help, -h             display this help and exit
EOF
  exit 0
}

# defaults
WITHOUT_TIMESTAMP=yes
UID_MAX=65535
GID_MAX=65535

for x; do
  opt=${x%%=*}
  var=${x#*=}
  case "$opt" in
  --prefix) PREFIX=$var ;;
  --exec-prefix) EPREFIX=$var ;;
  --bindir) BINDIR=$var ;;
  --datadir) SHAREDIR=$var ;;
  --mandir) MANDIR=$var ;;
  --sysconfdir) SYSCONFDIR=$var ;;
  --build) BUILD=$var ;;
  --host) HOST=$var ;;
  --target) TARGET=$var ;;
  --enable-debug) DEBUG=yes ;;
  --enable-static) BUILD_STATIC=yes ;;
  --without-insults) WITHOUT_INSULTS=yes ;;
  --with-timestamp) WITHOUT_TIMESTAMP= ;;
  --without-timestamp) WITHOUT_TIMESTAMP=yes ;;
  --uid-max) UID_MAX=$var ;;
  --gid-max) UID_MAX=$var ;;
  --help|-h) usage ;;
  *) die "Error: unknown option $opt" ;;
  esac
done

CONFIG_MK=config.mk
CONFIG_H=config.h
rm -f "$CONFIG_MK" "$CONFIG_H"

cat <<! >$CONFIG_H
#ifndef CONFIG_H
#define CONFIG_H

!

if [ -z "$BUILD" ]; then
  BUILD="$(uname -m)-unknown-$(uname -s | tr '[:upper:]' '[:lower:]')"
fi
if [ -z "$HOST" ]; then
  [ -z "$TARGET" ] && TARGET=$BUILD
  HOST=$TARGET
fi
if [ -z "$TARGET" ]; then
  [ -z "$HOST" ] && HOST=$BUILD
  TARGET=$HOST
fi

if [ -z "$OS" ]; then
  # Derive OS from cpu-manufacturer-os-kernel
  CPU=${TARGET%%-*}
  REST=${TARGET#*-}
  MANU=${REST%%-*}
  REST=${REST#*-}
  OS=${REST%%-*}
  REST=${REST#*-}
  KERNEL=${REST%%-*}
fi

OS_CFLAGS="-D__${OS}__"

case "$OS" in
  linux)
    printf 'Setting UID_MAX\t\t\t\t%d.\n' "$UID_MAX" >&2
    printf '#define UID_MAX %s\n' "$UID_MAX" >>$CONFIG_H
    printf 'Setting GID_MAX\t\t\t\t%d.\n' "$GID_MAX" >&2
    printf '#define GID_MAX %s\n' "$GID_MAX" >>$CONFIG_H
    OS_CFLAGS="$OS_CFLAGS -D_DEFAULT_SOURCE -D_GNU_SOURCE"
    ;;
  netbsd)
    OS_CFLAGS="$OS_CFLAGS -D_OPENBSD_SOURCE"
    printf 'LDLIBS +=  -lutil\n' >>$CONFIG_MK
    : ${BINGRP:=wheel}
    ;;
  freebsd)
    printf 'LDLIBS +=  -lutil\n' >>$CONFIG_MK
    : ${BINGRP:=wheel}
    ;;
  darwin)
    : ${BINGRP:=wheel}
    ;;
esac

: ${PREFIX:=/usr/local}
: ${EPREFIX:=${PREFIX}}
: ${BINDIR:=${PREFIX}/bin}
: ${SHAREDIR:=${PREFIX}/share}
: ${MANDIR:=${SHAREDIR}/man}
: ${SYSCONFDIR:=/etc}
: ${BINMODE:=4755}
: ${BINOWN:=root}
: ${BINGRP:=root}

cat <<EOF >>$CONFIG_MK
PREFIX   ?=  ${PREFIX}
EPREFIX  ?=  ${EPREFIX}
BINDIR   ?=  ${BINDIR}
SHAREDIR ?=  ${SHAREDIR}
MANDIR   ?=  ${MANDIR}
SYSCONFDIR?=  ${SYSCONFDIR}
BINMODE  ?=  ${BINMODE}
BINOWN  ?=  ${BINOWN}
BINGRP  ?=  ${BINGRP}
EOF

[ -n "$OS_CFLAGS" ] && \
  printf 'OS_CFLAGS   +=  %s\n' "$OS_CFLAGS" >>$CONFIG_MK

[ -n "$DEBUG" ] && \
  printf 'CFLAGS   +=  -O0 -g\n' >>$CONFIG_MK

[ -n "$BUILD_STATIC" ] && \
  printf 'CFLAGS   +=  -static\n' >>$CONFIG_MK

# Add CPPFLAGS/CFLAGS/LDFLAGS/LDLIBS to CC for testing features
XCC="${CC:=cc} $CFLAGS $OS_CFLAGS $CPPFLAGS $LDFLAGS $LDLIBS"
# Make sure to disable --as-needed for CC tests.

case "$OS" in
  darwin) ;;
  *) XCC="$XCC -Wl,--no-as-needed" ;;
esac

check_func() {
  func="$1"; src="$2"; shift 2
  printf 'Checking for %-14s\t\t' "$func ..." >&2
  printf '%s\n' "$src" >"_$func.c"
  $XCC "_$func.c" -o "_$func" 2>/dev/null
  ret=$?
  rm -f "_$func.c" "_$func"
  upperfunc="$(printf '%s\n' "$func" | tr '[[:lower:]]' '[[:upper:]]')"
  if [ $ret -eq 0 ]; then
    printf 'yes.\n' >&2
    printf '#define HAVE_%s\n' "$upperfunc" >>$CONFIG_H
    return 0
  else
    printf '/* #define HAVE_%s */\n' "$upperfunc" >>$CONFIG_H
    printf 'no.\n' >&2
    return 1
  fi
}

authmethod() {
  src='
#include <shadow.h>
int main(void) {
  return 0;
}'

printf 'SRCS     +=  shadow.c\n' >>$CONFIG_MK
printf 'LDLIBS +=  -lcrypt\n' >>$CONFIG_MK
return 0
}

definsults() {
  printf 'SRCS  += insults.c\n' >>$CONFIG_MK
  [ -z "$WITHOUT_INSULTS" ] && {
    printf '#define DOAS_INSULTS\n' >>$CONFIG_H
  }
  return 0
}


persistmethod() {
  [ -z "$WITHOUT_TIMESTAMP" ] && {
    printf '#define USE_TIMESTAMP\n' >>$CONFIG_H
    printf 'SRCS  += timestamp.c\n' >>$CONFIG_MK
    printf 'timestamp\n'
    return 0
  }
  return 1
}

#
# Check for explicit_bzero().
#
src='
#include <string.h>
int main(void) {
  explicit_bzero(NULL, 0);
  return 0;
}'
check_func "explicit_bzero" "$src" || {
  printf 'SRCS +=  libopenbsd/explicit_bzero.c\n' >>$CONFIG_MK
}

#
# Check for strlcat().
#
src='
#include <string.h>
int main(void) {
  const char s1[] = "foo";
  char s2[10];
  strlcat(s2, s1, sizeof(s2));
  return 0;
}'
check_func "strlcat" "$src" || {
  printf 'SRCS +=  libopenbsd/strlcat.c\n' >>$CONFIG_MK
}

#
# Check for strlcpy().
#
src='
#include <string.h>
int main(void) {
  const char s1[] = "foo";
  char s2[10];
  strlcpy(s2, s1, sizeof(s2));
  return 0;
}'
check_func "strlcpy" "$src" || {
  printf 'SRCS +=  libopenbsd/strlcpy.c\n' >>$CONFIG_MK
}

#
# Check for errc().
#
src='
#include <err.h>
int main(void) {
  errc(0, 0, "");
  return 0;
}'
check_func "errc" "$src" || {
  printf 'SRCS +=  libopenbsd/errc.c\n' >>$CONFIG_MK
}

#
# Check for verrc().
#
src='
#include <stddef.h>
#include <err.h>
int main(void) {
  verrc(0, 0, "x", NULL);
  return 0;
}'
check_func "verrc" "$src" || {
  printf 'SRCS +=  libopenbsd/verrc.c\n' >>$CONFIG_MK
}

#
# Check for setprogname().
#
src='
#include <stdlib.h>
int main(void) {
  setprogname("");
  return 0;
}'
check_func "setprogname" "$src" || {
  printf 'SRCS +=  libopenbsd/progname.c\n' >>$CONFIG_MK
}

#
# Check for readpassphrase().
#
src='
#include <readpassphrase.h>
int main(void) {
  char buf[12];
  readpassphrase("", buf, sizeof(buf), 0);
  return 0;
}'
check_func "readpassphrase" "$src" || {
  printf 'SRCS +=  libopenbsd/readpassphrase.c\n' >>$CONFIG_MK
}

#
# Check for strtonum().
#
src='
#include <stdlib.h>
int main(void) {
  const char *errstr;
  strtonum("", 1, 64, &errstr);
  return 0;
}'
check_func "strtonum" "$src" || {
  printf 'SRCS +=  libopenbsd/strtonum.c\n' >>$CONFIG_MK
}

#
# Check for reallocarray().
#
src='
#include <stdlib.h>
int main(void) {
  reallocarray(NULL, 0, 0);
  return 0;
}'
check_func "reallocarray" "$src" || {
  printf 'SRCS +=  libopenbsd/reallocarray.c\n' >>$CONFIG_MK
}

#
# Check for execvpe().
#
src='
#include <unistd.h>
int main(void) {
  const char *p = { "", NULL };
  execvpe("", p, p);
  return 0;
}'
check_func "execvpe" "$src" || {
  printf 'SRCS +=  libopenbsd/execvpe.c\n' >>$CONFIG_MK
}

#
# Check for setresuid().
#
src='
#include <unistd.h>
int main(void) {
  setresuid(0, 0, 0);
  return 0;
}'
check_func "setresuid" "$src"
have_setresuid=$?

#
# Check for setresgid().
#
src='
#include <unistd.h>
int main(void) {
  setresgid(0, 0, 0);
  return 0;
}'
check_func "setresgid" "$src"
have_setresgid=$?

if [ $have_setresuid -eq 1 -o $have_setresgid -eq 1 ]; then
  printf 'SRCS +=  libopenbsd/bsd-setres_id.c\n' >>$CONFIG_MK
fi

#
# Check for setreuid().
#
src='
#include <unistd.h>
int main(void) {
  setreuid(0, 0);
  return 0;
}'
check_func "setreuid" "$src"


#
# Check for setregid().
#
src='
#include <unistd.h>
int main(void) {
  setregid(0, 0);
  return 0;
}'
check_func "setregid" "$src"

#
# Check for closefrom().
#
src='
#include <unistd.h>
int main(void) {
  closefrom(0);
  return 0;
}'
check_func "closefrom" "$src" || {
  printf 'SRCS +=  libopenbsd/closefrom.c\n' >>$CONFIG_MK
}

#
# Check for sysconf().
#
src='
#include <unistd.h>
int main(void) {
  (void)sysconf(0);
  return 0;
}'
check_func "sysconf" "$src"

#
# Check for dirfd().
#
src='
#include <dirent.h>
int main(void) {
  (void)dirfd(0);
  return 0;
}'
check_func "dirfd" "$src"

#
# Check for fcntl.h.
#
src='
#include <fcntl.h>
int main(void) {
  return 0;
}'
check_func "fcntl_h" "$src"

#
# Check for F_CLOSEM.
#
src='
#include <fcntl.h>
#ifndef F_CLOSEM
#error no F_CLOSEM
#endif
int main(void) {
  return 0;
}'
check_func "F_CLOSEM" "$src"

#
# Check for dirent.h.
#
src='
#include <dirent.h>
int main(void) {
  return 0;
}'
check_func "dirent_h" "$src"

#
# Check for sys/ndir.h.
#
src='
#include <sys/ndir.h>
int main(void) {
  return 0;
}'
check_func "sys_ndir_h" "$src"

#
# Check for sys/dir.h.
#
src='
#include <sys/dir.h>
int main(void) {
  return 0;
}'
check_func "sys_dir_h" "$src"

#
# Check for ndir.h.
#
src='
#include <ndir.h>
int main(void) {
  return 0;
}'
check_func "ndir_h" "$src"

#
# Check for login_cap.h.
#
src='
#include <sys/types.h>
#include <login_cap.h>
int main(void) {
  return 0;
}'
check_func "login_cap_h" "$src"

#
#
#
src='
#include <stdlib.h>
int main(void){return 0;}
__attribute__((__unused__)) static void foo(void){return;}
'
check_func "__attribute__" "$src" || {
  printf 'OS_CFLAGS  +=  -DNO_ATTRIBUTE_ON_RETURN_TYPE=1\n' >>$CONFIG_MK
}

auth=$(authmethod)

insults=$(definsults)

persist=$(persistmethod)
if [ $? -eq 0 ]; then
  printf 'Using persist method\t\t\t%s.\n' "$persist" >&2
else
  printf 'Using persist method\t\t\tnone.\n' >&2
fi

printf '#define DOAS_CONF "%s/doas.conf"\n' "${SYSCONFDIR}" >>$CONFIG_H

printf '\n#endif /* CONFIG_H */\n' >>$CONFIG_H