#!/bin/bash
# Run an interactive git bisect on wireshark (wireshark-gtk by default)
#
# Usage:
# 1. Mark commits as good/bad (see man git-bisect)
#    git bisect start <bad commit> <good commit>
# 2. Optionally change the default target:
#    export WIRESHARK_BIN=wireshark-gtk # for wireshark-gtk
#    export WIRESHARK_BIN=              # build everything
# 3. Start the interactive bisect:
#    git bisect run ../wireshark-notes/bisect-wireshark
# 4. After the script returns, the faulty commit is identified.

# Wireshark program to build and launch (leave it empty to build everything)
WIRESHARK_BIN=${WIRESHARK_BIN-wireshark}
OUTDIR=/tmp/wsbuild
buildlogdir=/tmp/wslogs

SRCDIR=$(git rev-parse --show-toplevel)
ver=$(git describe)
buildlog=$buildlogdir/build-$(date +%Y-%m-%d-%H%M%S)-${ver}.txt

mkdir -p "$buildlogdir" "$OUTDIR"
if ! cd "$OUTDIR"; then
    echo "Failed to create output dir"
    exit 128 # abort
fi

make_local() {
    CFLAGS="-fsanitize=address -fsanitize=undefined -fdiagnostics-color=auto"
    set -x # Print commands as they are executed
    # Configure
    time cmake "$SRCDIR" -DCMAKE_BUILD_TYPE=Debug \
        -DCMAKE_C_FLAGS="$CFLAGS" -DCMAKE_CXX_FLAGS="$CFLAGS" &&
    # Build
    time make -C "$OUTDIR" -j$(nproc) $WIRESHARK_BIN
}

# Export variables and build locally (need recent Bash versions, the one
# included with Ubuntu 12.04 won't do)
script -e -c "date -R; $(declare -p WIRESHARK_BIN SRCDIR OUTDIR);
$(declare -pf make_local); time make_local" "$buildlog"
rc=$?
if [ $rc = 0 ]; then
    echo "Build OK"
else
    printf '\e[1;31m%\e[m\n' "Build failed with $rc"
fi

# Run it and interactively ask the user to tell whether it passed or not
while true; do
    if [ -n "$WIRESHARK_BIN" ]; then
        "$OUTDIR/run/$WIRESHARK_BIN"
    fi

    cat <<EOF

Commit: $ver
Did it work?

 0) Yes.
 1) No.
 2) Not sure (skip this commit).
 3) Abort bisect, let me manually check.
 x) I need to re-check (run $WIRESHARK_BIN again).

EOF
    read -p 'Your choice: ' choice
    case $choice in
    0)
        echo Pass
        exit 0
        ;;
    1)
        echo FAIL
        exit 1
        ;;
    2)
        echo Skip
        exit 125
        ;;
    3)
        echo Abort
        exit 128
        ;;
    x)
        ;;
    *)
        echo "Unrecognized option '$choice'"
        ;;
    esac
done