#!/usr/bin/env bash
# SPDX-License-Identifier: GPL-2.0
# Linux kernel coccicheck
#
# Read Documentation/dev-tools/coccinelle.rst
#
# This script requires at least spatch
# version 1.0.0-rc11.

DIR="$(dirname $(readlink -f $0))/.."
SPATCH="`which ${SPATCH:=spatch}`"

if [ ! -x "$SPATCH" ]; then
    echo 'spatch is part of the Coccinelle project and is available at http://coccinelle.lip6.fr/'
    exit 1
fi

SPATCH_VERSION=$($SPATCH --version | head -1 | awk '{print $3}')

USE_JOBS="no"
$SPATCH --help | grep -e "--jobs" > /dev/null && USE_JOBS="yes"

# The verbosity may be set by the environmental parameter V=
# as for example with 'make V=1 coccicheck'

if [ -n "$V" -a "$V" != "0" ]; then
	VERBOSE="$V"
else
	VERBOSE=0
fi

FLAGS="--very-quiet"

# You can use SPFLAGS to append extra arguments to coccicheck or override any
# heuristics done in this file as Coccinelle accepts the last options when
# options conflict.
#
# A good example for use of SPFLAGS is if you want to debug your cocci script,
# you can for instance use the following:
#
# $ export COCCI=scripts/coccinelle/misc/irqf_oneshot.cocci
# $ make coccicheck MODE=report DEBUG_FILE="all.err" SPFLAGS="--profile --show-trying" M=./drivers/mfd/arizona-irq.c
#
# "--show-trying" should show you what rule is being processed as it goes to
# stdout, you do not need a debug file for that. The profile output will be
# be sent to stdout, if you provide a DEBUG_FILE the profiling data can be
# inspected there.
#
# --profile will not output if --very-quiet is used, so avoid it.
echo $SPFLAGS | grep -E -e "--profile|--show-trying" 2>&1 > /dev/null
if [ $? -eq 0 ]; then
	FLAGS="--quiet"
fi

# spatch only allows include directories with the syntax "-I include"
# while gcc also allows "-Iinclude" and "-include include"
COCCIINCLUDE=${LINUXINCLUDE//-I/-I }
COCCIINCLUDE=${COCCIINCLUDE// -include/ --include}

if [ "$C" = "1" -o "$C" = "2" ]; then
    ONLINE=1

    if [[ $# -le 0 ]]; then
	    echo ''
	    echo 'Specifying both the variable "C" and rule "coccicheck" in the make
command results in a shift count error.'
	    echo ''
	    echo 'Try specifying "scripts/coccicheck" as a value for the CHECK variable instead.'
	    echo ''
	    echo 'Example:	make C=2 CHECK=scripts/coccicheck drivers/net/ethernet/ethoc.o'
	    echo ''
	    exit 1
    fi

    # Take only the last argument, which is the C file to test
    shift $(( $# - 1 ))
    OPTIONS="$COCCIINCLUDE $1"

    # No need to parallelize Coccinelle since this mode takes one input file.
    NPROC=1
else
    ONLINE=0
    OPTIONS="--dir $srcroot $COCCIINCLUDE"

    # Use only one thread per core by default if hyperthreading is enabled
    THREADS_PER_CORE=$(LANG=C lscpu | grep "Thread(s) per core: " | tr -cd "[:digit:]")
    if [ -z "$J" ]; then
        NPROC=$(getconf _NPROCESSORS_ONLN)
	if [ $THREADS_PER_CORE -gt 1 -a $NPROC -gt 4 ] ; then
		NPROC=$((NPROC/2))
	fi
    else
        NPROC="$J"
    fi
fi

if [ "$KBUILD_EXTMOD" != "" ] ; then
    OPTIONS="--patch $srctree $OPTIONS"
fi

# You can override by using SPFLAGS
if [ "$USE_JOBS" = "no" ]; then
	trap kill_running SIGTERM SIGINT
	declare -a SPATCH_PID
elif [ "$NPROC" != "1" ]; then
	# Using 0 should work as well, refer to _SC_NPROCESSORS_ONLN use on
	# https://github.com/rdicosmo/parmap/blob/master/setcore_stubs.c
	OPTIONS="$OPTIONS --jobs $NPROC --chunksize 1"
fi

if [ "$MODE" = "" ] ; then
    if [ "$ONLINE" = "0" ] ; then
	echo 'You have not explicitly specified the mode to use. Using default "report" mode.'
	echo 'Available modes are the following: patch, report, context, org, chain'
	echo 'You can specify the mode with "make coccicheck MODE=<mode>"'
	echo 'Note however that some modes are not implemented by some semantic patches.'
    fi
    MODE="report"
fi

if [ "$MODE" = "chain" ] ; then
    if [ "$ONLINE" = "0" ] ; then
	echo 'You have selected the "chain" mode.'
	echo 'All available modes will be tried (in that order): patch, report, context, org'
    fi
elif [ "$MODE" = "report" -o "$MODE" = "org" ] ; then
    FLAGS="--no-show-diff $FLAGS"
fi

if [ "$ONLINE" = "0" ] ; then
    echo ''
    echo 'Please check for false positives in the output before submitting a patch.'
    echo 'When using "patch" mode, carefully review the patch before submitting it.'
    echo ''
fi

run_cmd_parmap() {
	if [ $VERBOSE -ne 0 ] ; then
		echo "Running ($NPROC in parallel): $@"
	fi
	if [ "$DEBUG_FILE" != "/dev/null" ]; then
                echo $@>>$DEBUG_FILE
                $@ 2>>$DEBUG_FILE
        else
                echo $@
                $@ 2>&1
	fi

	err=$?
	if [[ $err -ne 0 ]]; then
		echo "coccicheck failed"
		exit $err
	fi
}

run_cmd_old() {
	local i
	if [ $VERBOSE -ne 0 ] ; then
		echo "Running ($NPROC in parallel): $@"
	fi
	for i in $(seq 0 $(( NPROC - 1)) ); do
		eval "$@ --max $NPROC --index $i &"
		SPATCH_PID[$i]=$!
		if [ $VERBOSE -eq 2 ] ; then
			echo "${SPATCH_PID[$i]} running"
		fi
	done
	wait
}

run_cmd() {
	if [ "$USE_JOBS" = "yes" ]; then
		run_cmd_parmap $@
	else
		run_cmd_old $@
	fi
}

kill_running() {
	for i in $(seq 0 $(( NPROC - 1 )) ); do
		if [ $VERBOSE -eq 2 ] ; then
			echo "Killing ${SPATCH_PID[$i]}"
		fi
		kill ${SPATCH_PID[$i]} 2>/dev/null
	done
}

# You can override heuristics with SPFLAGS, these must always go last
OPTIONS="$OPTIONS $SPFLAGS"

coccinelle () {
    COCCI="$1"

    OPT=`grep "Options:" $COCCI | cut -d':' -f2`
    REQ=`grep "Requires:" $COCCI | cut -d':' -f2 | sed "s| ||"`
    if [ -n "$REQ" ] && ! { echo "$REQ"; echo "$SPATCH_VERSION"; } | sort -CV ; then
	    echo "Skipping coccinelle SmPL patch: $COCCI"
	    echo "You have coccinelle:           $SPATCH_VERSION"
	    echo "This SmPL patch requires:      $REQ"
	    return
    fi

#   The option '--parse-cocci' can be used to syntactically check the SmPL files.
#
#    $SPATCH -D $MODE $FLAGS -parse_cocci $COCCI $OPT > /dev/null

    if [ $VERBOSE -ne 0 -a $ONLINE -eq 0 ] ; then

	FILE=${COCCI#$srctree/}

	echo "Processing `basename $COCCI`"
	echo "with option(s) \"$OPT\""
	echo ''
	echo 'Message example to submit a patch:'

	sed -ne 's|^///||p' $COCCI

	if [ "$MODE" = "patch" ] ; then
	    echo ' The semantic patch that makes this change is available'
	elif [ "$MODE" = "report" ] ; then
	    echo ' The semantic patch that makes this report is available'
	elif [ "$MODE" = "context" ] ; then
	    echo ' The semantic patch that spots this code is available'
	elif [ "$MODE" = "org" ] ; then
	    echo ' The semantic patch that makes this Org report is available'
	else
	    echo ' The semantic patch that makes this output is available'
	fi
	echo " in $FILE."
	echo ''
	echo ' More information about semantic patching is available at'
	echo ' http://coccinelle.lip6.fr/'
	echo ''

	if [ "`sed -ne 's|^//#||p' $COCCI`" ] ; then
	    echo 'Semantic patch information:'
	    sed -ne 's|^//#||p' $COCCI
	    echo ''
	fi
    fi

    if [ "$MODE" = "chain" ] ; then
	run_cmd $SPATCH -D patch   \
		$FLAGS --cocci-file $COCCI $OPT $OPTIONS               || \
	run_cmd $SPATCH -D report  \
		$FLAGS --cocci-file $COCCI $OPT $OPTIONS --no-show-diff || \
	run_cmd $SPATCH -D context \
		$FLAGS --cocci-file $COCCI $OPT $OPTIONS               || \
	run_cmd $SPATCH -D org     \
		$FLAGS --cocci-file $COCCI $OPT $OPTIONS --no-show-diff || exit 1
    elif [ "$MODE" = "rep+ctxt" ] ; then
	run_cmd $SPATCH -D report  \
		$FLAGS --cocci-file $COCCI $OPT $OPTIONS --no-show-diff && \
	run_cmd $SPATCH -D context \
		$FLAGS --cocci-file $COCCI $OPT $OPTIONS || exit 1
    else
	run_cmd $SPATCH -D $MODE   $FLAGS --cocci-file $COCCI $OPT $OPTIONS || exit 1
    fi

}

if [ "$DEBUG_FILE" = "" ]; then
    echo 'You have not explicitly specified the debug file to use.'
    echo 'Using default "/dev/null" as debug file.'
    echo 'Debug logs will be printed to stdout.'
    echo 'You can specify the debug file with "make coccicheck DEBUG_FILE=<debug_file>"'
    echo ''
    DEBUG_FILE="/dev/null"
fi

if [ -f $DEBUG_FILE ]; then
	echo "Debug file $DEBUG_FILE exists, bailing"
	exit
fi

if [ "$COCCI" = "" ] ; then
    for f in `find $srctree/scripts/coccinelle/ -name '*.cocci' -type f | sort`; do
        if grep -q "virtual[[:space:]]\+$MODE" "$f"; then
                coccinelle $f
        else
                echo "warning: Skipping $f as it does not match mode '$MODE'"
        fi
    done
else
    coccinelle $COCCI
fi