scripts/coccicheck

#!/bin/bash
# Linux kernel coccicheck
#
# For more detailed documentation refer to:
#
# https://bottest.wiki.kernel.org/coccicheck
#
# This documentation always refers to the linux-next version of the script.
#
# 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 $3}')
SPATCH_VERSION_NUM=$(echo $SPATCH_VERSION | ${DIR}/scripts/ld-version.sh)

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

function can_use_glimpse()
{
	$SPATCH --help | grep "\-\-use\-glimpse" > /dev/null
	if [ $? -ne 0 ]; then
		echo "no"
		return
	fi
	if [ ! -f $DIR/.glimpse_index ]; then
		echo "no"
		return
	fi

	# As of coccinelle 1.0.5 --use-glimpse cannot be used with M= other
	# than the base directory. We expect a future release will let us
	# specify the full path of the glimpse index but even if that's
	# supported, glimpse use seems to require an index per every
	# directory parsed, so you'd have to generate a glimpse index
	# per directory. If M=path is used (where epath is not the top level)
	# we'll have to fallback to alternatives then.
	if [ "$KBUILD_EXTMOD" != "./" -a "$KBUILD_EXTMOD" != "" ]; then
		echo "no"
		return
	fi
	echo yes
}

function can_use_idutils()
{
	$SPATCH --help | grep "\-\-use\-idutils" > /dev/null
	if [ $? -ne 0 ]; then
		echo "no"
		return
	fi
	# As of coccinelle 1.0.5 --use-idutils will bust if one uses
	# idutils with an index out of the main tree.
	if [ "$KBUILD_EXTMOD" != "./" -a "$KBUILD_EXTMOD" != "" ]; then
		echo "no"
		return
	fi
	if [ -f $DIR/ID -o -f $DIR/.id-utils.index ]; then
		echo "yes"
		return
	fi
	echo "no"
}

function can_use_gitgrep()
{
	$SPATCH --help | grep "\-\-use\-gitgrep" > /dev/null
	if [ $? -ne 0 ]; then
		echo "no"
		return
	fi
	if [ ! -d $DIR/.git ]; then
		echo "no"
		return
	fi
	echo "yes"
}

# Indexing USE_* optimizations heuristics.
#
# Linux runs on git (TM). However, if you have supplemental indexing options
# you may use them to help Coccinelle further. If you are using Coccinelle
# within a target git tree --use-gitrep will be used, and this should
# suffice for most uses. If you however want optimal performance do
# consider embracing a supplemental indexing as part of your development.
# For instance glimpse, and idutils can be used, however you should
# be sure to update the indexes as often as you update your git tree to
# ensure your indexes are not stale.
#
# idutils is currently not as efficient as glimpse because the query language
# for glimpse is simpler, so when idutils is used more filtering has to be
# done at the ocaml level within Coccinelle. Glimpse allows queries that are
# arbitrary formulas, up to a limited level of complexity, involving both
# && and ||. For idutils, Coccinelle runs lid intersections on the result.
#
# You can override these heuristics with COCCI_INDEX="--use-gitgrep" for
# example. This will force to use --use-gitgrep even if you have a glimpse
# index. Other examples:
#
# $ export COCCI=scripts/coccinelle/misc/irqf_oneshot.cocci
# $ make coccicheck V=1 MODE=report COCCI_INDEX="--use-coccigrep"
# $ make coccicheck V=1 MODE=report COCCI_INDEX="--use-idutils ID"
# $ make coccicheck V=1 MODE=report COCCI_INDEX="--use-glimpse"
# $ make coccicheck V=1 MODE=report COCCI_INDEX="--use-gitgrep"
#
# The order of heuristics for indexing used by coccicheck is listed below.
#
# 0. Glimpse currently should outperform all indexing options. so if a glimpse
#    index is used we use it. Refer to Linux scripts/glimpse.sh for details.
#    If you think you should be getting better performance with glimpse than
#    what you would expect inspect the stderr log file for cocciecheck, you
#    ask for a debug file with DEBUG_FILE="" parameter to coccicheck.
#
#    If glimpse is running correctly there should be very few occurrences
#    of "Skipping", also coccinelle will inform you if it could not use
#    glimpse. As an example an output of the following would indicate glimpse
#    was properly used on the stderr log file:
#
#    There are matches to 1252 out of 47281 files
#    glimpse request = request_threaded_irq
#
# 1. Use idutils next. You'll need to generate an index using either of these:
#
#	a) mkid -s
#       By default this dumps the index into ./ID
#
#	b) mkid -i C --output .id-utils.index *
#       This method is provided with coccinelle repo on
#       scripts/idutils_index.sh
#
# 2. Next best is --use-gitgrep and if you are working within a git tree
#    this will be used by default.
#
# 3. By default coccinelle internally uses --use-coccigrep if no indexing
#    options are requested and your version of coccinelle supports it so we
#    do not need to be specific about requesting that as a fallback mechanism.
#    Use of --use-coccigrep is comparable to --use-gitgrep.
#
# XXX: Glimpse is not well maintained. See if we can add similar indexing
# features and query language glimpse supports to git.
if [ "$COCCI_INDEX" = "" ] ; then
	USE_GLIMPSE=$(can_use_glimpse)
	USE_IDUTILS=$(can_use_idutils)
	USE_GITGREP=$(can_use_gitgrep)
fi

# 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

if [ -z "$J" ]; then
	NPROC=$(getconf _NPROCESSORS_ONLN)
else
	NPROC="$J"
fi

# You can use SPFLAGS to append extra arguments to coccicheck.
# A good example is if you want to debug your cocci script, you can
# for instance use the following:
#
# $ export COCCI=scripts/coccinelle/misc/irqf_oneshot.cocci
# $ time 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 | egrep -e "--profile|--show-trying" 2>&1 > /dev/null
if [ $? -eq 0 ]; then
	FLAGS="--quiet $SPFLAGS"
else
	FLAGS="--very-quiet $SPFLAGS"
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

    # Take only the last argument, which is the C file to test
    shift $(( $# - 1 ))
    OPTIONS="$COCCIINCLUDE $1"
else
    ONLINE=0
    if [ "$KBUILD_EXTMOD" = "" ] ; then
        OPTIONS="--dir $srctree $COCCIINCLUDE"
    else
        OPTIONS="--dir $KBUILD_EXTMOD $COCCIINCLUDE"
    fi
fi

if [ "$KBUILD_EXTMOD" != "" ] ; then
    OPTIONS="--patch $srctree $OPTIONS"
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'
	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="$FLAGS --no-show-diff"
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

if [ "$USE_JOBS" = "no" ]; then
	trap kill_running SIGTERM SIGINT
	declare -a SPATCH_PID
else
	OPTIONS="$OPTIONS --jobs $NPROC --chunksize 1"
fi

# Check COCCI_INDEX first to manual override, otherwise rely on
# internal heuristics documented above.
if [ "$COCCI_INDEX" != "" ] ; then
	OPTIONS="$OPTIONS $COCCI_INDEX"
elif [ "$USE_GLIMPSE" = "yes" ]; then
	OPTIONS="$OPTIONS --use-glimpse"
elif [ "$USE_IDUTILS" = "yes" ]; then
	index=""
	if [ -f $DIR/ID ]; then
		index="$DIR/ID"
	elif [ -f $DIR/.id-utils.index ]; then
		index="$DIR/.id-utils.index"
	else
		echo "idutils index not found, expected: $DIR/ID or $DIR/.id-utils.index"
		exit 1
	fi
	OPTIONS="$OPTIONS --use-idutils $index"
elif [ "$USE_GITGREP" = "yes" ]; then
	OPTIONS="$OPTIONS --use-gitgrep"
fi

run_cmd_parmap() {
	if [ $VERBOSE -ne 0 ] ; then
		echo "Running ($NPROC in parallel): $@"
	fi
	if [ "$DEBUG_FILE" != "/dev/null" -a "$DEBUG_FILE" != "" ]; then
		if [ -f $DEBUG_FILE ]; then
			echo "Debug file $DEBUG_FILE exists, bailing"
			exit
		fi
	else
		DEBUG_FILE="/dev/null"
	fi
	$@ 2>$DEBUG_FILE
	if [[ $? -ne 0 ]]; then
		echo "coccicheck failed"
		exit $?
	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
}

coccinelle () {
    COCCI="$1"

    OPT=`grep "Option" $COCCI | cut -d':' -f2`
    REQ=`grep "Requires" $COCCI | cut -d':' -f2 | sed "s| ||"`
    REQ_NUM=$(echo $REQ | ${DIR}/scripts/ld-version.sh)
    if [ "$REQ_NUM" != "0" ] ; then
	    if [ "$SPATCH_VERSION_NUM" -lt "$REQ_NUM" ] ; then
		    echo "Skipping coccinele SmPL patch: $COCCI"
		    echo "You have coccinelle:           $SPATCH_VERSION"
		    echo "This SmPL patch requires:      $REQ"
		    return
	    fi
    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=`echo $COCCI | sed "s|$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 [ "$COCCI" = "" ] ; then
    for f in `find $srctree/scripts/coccinelle/ -name '*.cocci' -type f | sort`; do
	coccinelle $f
    done
else
    coccinelle $COCCI
fi