activate

#!/bin/bash

# The MIT License (MIT)
#
# Copyright (c) 2015 StarBrilliant <m13253@hotmail.com>
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.

set -e

print_help() {
    cat<<EOM
Usage: Interactive mode:   $0
       Batch mode:         $0 - command
       Cross compile mode: $0 host-triple command

EOM
    exit
}

main() {
    TRIPLE=
    if [ "$#" -ge 1 ]
    then
        if [ "$1" = '--help' ]
        then
            print_help
        elif [ -n "$1" -a "$1" != '-' ]
        then
            TRIPLE="$1"-
        fi
        shift
    fi
    if [ "$#" -ne 0 ]
    then
        CHILD_CMD=("$@")
    else
        CHILD_CMD=("${SHELL:-bash}" -i)
    fi
    TEMPDIR="$(mktemp -d --tmpdir ltowrapper.XXXXXXXXXX)"
    [ -z "$TEMPDIR" ] && exit 2
    QUOTE_PATH="$(printf %q "$PATH")"
    ARCHIVER=(ar nm ranlib)
    for COMMAND in "${ARCHIVER[@]}"
    do
        REAL_COMMAND="$(printf %q "${TRIPLE}gcc-$COMMAND")"
        for i in "$COMMAND" "$TRIPLE$COMMAND" "gcc-$COMMAND" "${TRIPLE}gcc-$COMMAND"
        do
            cat >"$TEMPDIR/$i" <<EOM
#!/bin/bash

PATH=$QUOTE_PATH exec -- $REAL_COMMAND "\$@"
EOM
            chmod +x "$TEMPDIR/$i"
        done
        echo "Created \"$TRIPLE$COMMAND\"" >&2
    done
    COMPILER=(cc c++ gcc g++)
    for COMMAND in "${COMPILER[@]}"
    do
        REAL_COMMAND="$(printf %q "$TRIPLE$COMMAND")"
        for i in "$COMMAND" "$TRIPLE$COMMAND"
        do
            cat >"$TEMPDIR/$i" <<EOM
#!/bin/bash

for i in "\$@"
do
    if [ "\$i" = '-fno-lto' ]
    then
        PATH=$QUOTE_PATH exec -- $REAL_COMMAND "\$@"
        exit "\$?"
    fi
done
PATH=$QUOTE_PATH exec -- $REAL_COMMAND -flto -fuse-linker-plugin "\$@"
EOM
            chmod +x "$TEMPDIR/$i"
        done
        echo "Created \"$TRIPLE$COMMAND\"" >&2
    done
    if [ "$#" -eq 0 ]
    then
        echo "Starting \"${CHILD_CMD[0]}\" shell, type \"exit\" when you finish." >&2
    fi
    PATH="$TEMPDIR:$PATH" \
        AR="$TEMPDIR/${TRIPLE}gcc-ar" \
        CC="$TEMPDIR/${TRIPLE}gcc" \
        CXX="$TEMPDIR/${TRIPLE}g++" \
        NM="$TEMPDIR/${TRIPLE}gcc-nm" \
        RANLIB="$TEMPDIR/${TRIPLE}gcc-ranlib" \
        "${CHILD_CMD[@]}"
    rm -rfv "$TEMPDIR"
}

main "$@"