#!/bin/sh
# replacement for c++ command
#
# we assume you run the following beforehand
#
#     sudo chmod 1777 /opt
#     cd /opt
#     git clone https://github.com/jart/cosmopolitan cosmo
#     cd cosmo
#     make -j
#
# you can then use it to build open source projects, e.g.
#
#     export CC=cosmocc
#     export CXX=cosmoc++
#     export LD=cosmoc++
#     ./configure --prefix=/opt/cosmos
#     make -j
#     make install
#

COSMO=/opt/cosmo
COSMOS=/opt/cosmos

if [ "$1" = "--version" ]; then
cat <<'EOF'
x86_64-unknown-cosmo-g++ (GCC) 11.2.0
Copyright (C) 2019 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
EOF
exit 0
fi

UNDEF="-D__COSMOPOLITAN__"
PREDEF="-include libc/integral/normalize.inc"
CXX="$COSMO/o/third_party/gcc/bin/x86_64-linux-musl-g++"
OBJCOPY="$COSMO/o/third_party/gcc/bin/x86_64-linux-musl-objcopy"
CCFLAGS="-g -fdata-sections -ffunction-sections -fno-pie -mno-tls-direct-seg-refs -mno-red-zone -fportcosmo"
CXXFLAGS="-fno-exceptions -fuse-cxa-atexit -fno-threadsafe-statics"
CPPFLAGS="-DNDEBUG -nostdinc -iquote /opt/cosmo -isystem $COSMOS/include -isystem $COSMO/libc/isystem"
LDFLAGS="-static -no-pie -nostdlib -fuse-ld=bfd -Wl,-melf_x86_64 -Wl,--gc-sections -L$COSMOS/lib -Wl,-T,$COSMO/o/ape/public/ape.lds $COSMO/o/ape/ape-no-modify-self.o $COSMO/o/libc/crt/crt.o"
LDLIBS="$COSMO/o/third_party/libcxx/libcxx.a $COSMO/o/cosmopolitan.a"

if [ ! -d "$COSMO" ]; then
  echo "you need to checkout cosmopolitan to your $COSMO directory" >&2
  exit 1
fi

if [ ! -d "$COSMOS" ]; then
  echo "you need to create your $COSMOS directory" >&2
  exit 1
fi

# auto-install some shell libraries
if [ ! -d "$COSMOS/lib" ]; then
  mkdir "$COSMOS/lib"
  for lib in c dl gcc_s m pthread resolv rt z stdc++; do
    printf '\041\074\141\162\143\150\076\012' >"$COSMOS/lib/lib$lib.a"
  done
fi

OPT=
HAS_C=0
HAS_O=0
HAS_E=0
FIRST=1
OUTPUT=
NEED_OUTPUT=
FRAME=-fno-omit-frame-pointer
for x; do
  if [ $FIRST -eq 1 ]; then
    set --
    FIRST=0
  fi
  if [ x"$x" = x"-Werror" ]; then
    # this toolchain is intended for building other people's code
    # elevating warnings into errors, should only be done by devs
    continue
  elif [ x"$x" = x"-pedantic" ]; then
    # this toolchain is intended for building other people's code
    # we don't need the compiler's assistance to be more portable
    continue
  elif [ x"$x" != x"${x#-O}" ]; then
    OPT=$x
  elif [ x"$x" = x"-c" ]; then
    HAS_C=1
  elif [ x"$x" = x"-E" ]; then
    HAS_E=1
  elif [ x"$x" = x"-o" ]; then
    HAS_O=1
    NEED_OUTPUT=1
  elif [ x"$x" != x"${x#-o}" ]; then
    HAS_O=1
    OUTPUT=${x#-o}
  elif [ -n "$NEED_OUTPUT" ]; then
    NEED_OUTPUT=
    OUTPUT=$x
  elif [ x"$x" = x"-fpic" ]; then
    continue
  elif [ x"$x" = x"-fPIC" ]; then
    continue
  elif [ x"$x" = x"-shared" ]; then
    echo "error: cosmocc -shared isn't supported" >&2
    exit 1
  elif [ x"$x" = x"-fomit-frame-pointer" ] || [ x"$x" = x"-fno-omit-frame-pointer" ]; then
    FRAME=$x
    continue
  fi
  set -- "$@" "$x"
done

if [ x"$OPT" != x"-Os" ]; then
  # support --ftrace unless optimizing for size
  CXXFLAGS="$CXXFLAGS -fpatchable-function-entry=18,16"
fi

LINKING=
if [ "$HAS_E" = "1" ]; then
  set -- $UNDEF $CCFLAGS $CPPFLAGS "$@"
elif [ "$HAS_C" = "1" ]; then
  set -- $UNDEF $PREDEF $CCFLAGS $CXXFLAGS $CPPFLAGS "$@" $FRAME
else
  LINKING=1
  set -- $UNDEF $PREDEF $LDFLAGS $CXXFLAGS $CPPFLAGS "$@" $LDLIBS -Wl,-z,common-page-size=65536 -Wl,-z,max-page-size=65536 $FRAME
fi

set -- "$CXX" "$@"
printf '(cd %s; %s)\n' "$PWD" "$*" >>/tmp/build.log
"$@" || exit

if [ -n "$LINKING" ] && [ x"$OUTPUT" != x"" ]; then
  if [ x"$OUTPUT" != x"${OUTPUT%.com}" ] ||
     [ x"$OUTPUT" != x"${OUTPUT%.exe}" ]; then
    # cosmocc -o foo.com ...
    # -> foo.com (ape)
    # -> foo.com.dbg (elf)
    mv -f "$OUTPUT" "$OUTPUT.dbg" || exit
    "$OBJCOPY" -S -O binary "$OUTPUT.dbg" "$OUTPUT" || exit
  else
    # cosmocc -o foo ...
    # -> foo (elf)
    # -> foo.com (ape)
    # -> foo.com.dbg (elf)
    cp -f "$OUTPUT" "$OUTPUT.com.dbg" || exit
    "$OBJCOPY" -S -O binary "$OUTPUT" "$OUTPUT.com" || exit
  fi
fi