From c8bae7493d2f2910b57f13ded012e86bdcfb0532 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 16:47:53 +0200 Subject: Adding upstream version 1:2.39.2. Signed-off-by: Daniel Baumann --- contrib/coccinelle/spatchcache | 304 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 304 insertions(+) create mode 100755 contrib/coccinelle/spatchcache (limited to 'contrib/coccinelle/spatchcache') diff --git a/contrib/coccinelle/spatchcache b/contrib/coccinelle/spatchcache new file mode 100755 index 0000000..29e9352 --- /dev/null +++ b/contrib/coccinelle/spatchcache @@ -0,0 +1,304 @@ +#!/bin/sh +# +# spatchcache: a poor-man's "ccache"-alike for "spatch" in git.git +# +# This caching command relies on the peculiarities of the Makefile +# driving "spatch" in git.git, in particular if we invoke: +# +# make +# # See "spatchCache.cacheWhenStderr" for why "--very-quiet" is +# # used +# make coccicheck SPATCH_FLAGS=--very-quiet +# +# We can with COMPUTE_HEADER_DEPENDENCIES (auto-detected as true with +# "gcc" and "clang") write e.g. a .depend/grep.o.d for grep.c, when we +# compile grep.o. +# +# The .depend/grep.o.d will have the full header dependency tree of +# grep.c, and we can thus cache the output of "spatch" by: +# +# 1. Hashing all of those files +# 2. Hashing our source file, and the *.cocci rule we're +# applying +# 3. Running spatch, if suggests no changes (by far the common +# case) we invoke "spatchCache.getCmd" and +# "spatchCache.setCmd" with a hash SHA-256 to ask "does this +# ID have no changes" or "say that ID had no changes> +# 4. If no "spatchCache.{set,get}Cmd" is specified we'll use +# "redis-cli" and maintain a SET called "spatch-cache". Set +# appropriate redis memory policies to keep it from growing +# out of control. +# +# This along with the general incremental "make" support for +# "contrib/coccinelle" makes it viable to (re-)run coccicheck +# e.g. when merging integration branches. +# +# Note that the "--very-quiet" flag is currently critical. The cache +# will refuse to cache anything that has output on STDERR (which might +# be errors from spatch), but see spatchCache.cacheWhenStderr below. +# +# The STDERR (and exit code) could in principle be cached (as with +# ccache), but then the simple structure in the Redis cache would need +# to change, so just supply "--very-quiet" for now. +# +# To use this, simply set SPATCH to +# contrib/coccinelle/spatchcache. Then optionally set: +# +# [spatchCache] +# # Optional: path to a custom spatch +# spatch = ~/g/coccicheck/spatch.opt +# +# As well as this trace config (debug implies trace): +# +# cacheWhenStderr = true +# trace = false +# debug = false +# +# The ".depend/grep.o.d" can also be customized, as a string that will +# be eval'd, it has access to a "$dirname" and "$basename": +# +# [spatchCache] +# dependFormat = "$dirname/.depend/${basename%.c}.o.d" +# +# Setting "trace" to "true" allows for seeing when we have a cache HIT +# or MISS. To debug whether the cache is working do that, and run e.g.: +# +# redis-cli FLUSHALL +# +# grep -hore HIT -e MISS -e SET -e NOCACHE -e CANTCACHE .build/contrib/coccinelle | sort | uniq -c +# 600 CANTCACHE +# 7365 MISS +# 7365 SET +# +# A subsequent "make cocciclean && make coccicheck" should then have +# all "HIT"'s and "CANTCACHE"'s. +# +# The "spatchCache.cacheWhenStderr" option is critical when using +# spatchCache.{trace,debug} to debug whether something is set in the +# cache, as we'll write to the spatch logs in .build/* we'd otherwise +# always emit a NOCACHE. +# +# Reading the config can make the command much slower, to work around +# this the config can be set in the environment, with environment +# variable name corresponding to the config key. "default" can be used +# to use whatever's the script default, e.g. setting +# spatchCache.cacheWhenStderr=true and deferring to the defaults for +# the rest is: +# +# export GIT_CONTRIB_SPATCHCACHE_DEBUG=default +# export GIT_CONTRIB_SPATCHCACHE_TRACE=default +# export GIT_CONTRIB_SPATCHCACHE_CACHEWHENSTDERR=true +# export GIT_CONTRIB_SPATCHCACHE_SPATCH=default +# export GIT_CONTRIB_SPATCHCACHE_DEPENDFORMAT=default +# export GIT_CONTRIB_SPATCHCACHE_SETCMD=default +# export GIT_CONTRIB_SPATCHCACHE_GETCMD=default + +set -e + +env_or_config () { + env="$1" + shift + if test "$env" = "default" + then + # Avoid expensive "git config" invocation + return + elif test -n "$env" + then + echo "$env" + else + git config $@ || : + fi +} + +## Our own configuration & options +debug=$(env_or_config "$GIT_CONTRIB_SPATCHCACHE_DEBUG" --bool "spatchCache.debug") +if test "$debug" != "true" +then + debug= +fi +if test -n "$debug" +then + set -x +fi + +trace=$(env_or_config "$GIT_CONTRIB_SPATCHCACHE_TRACE" --bool "spatchCache.trace") +if test "$trace" != "true" +then + trace= +fi +if test -n "$debug" +then + # debug implies trace + trace=true +fi + +cacheWhenStderr=$(env_or_config "$GIT_CONTRIB_SPATCHCACHE_CACHEWHENSTDERR" --bool "spatchCache.cacheWhenStderr") +if test "$cacheWhenStderr" != "true" +then + cacheWhenStderr= +fi + +trace_it () { + if test -z "$trace" + then + return + fi + echo "$@" >&2 +} + +spatch=$(env_or_config "$GIT_CONTRIB_SPATCHCACHE_SPATCH" --path "spatchCache.spatch") +if test -n "$spatch" +then + if test -n "$debug" + then + trace_it "custom spatchCache.spatch='$spatch'" + fi +else + spatch=spatch +fi + +dependFormat='$dirname/.depend/${basename%.c}.o.d' +dependFormatCfg=$(env_or_config "$GIT_CONTRIB_SPATCHCACHE_DEPENDFORMAT" "spatchCache.dependFormat") +if test -n "$dependFormatCfg" +then + dependFormat="$dependFormatCfg" +fi + +set=$(env_or_config "$GIT_CONTRIB_SPATCHCACHE_SETCMD" "spatchCache.setCmd") +get=$(env_or_config "$GIT_CONTRIB_SPATCHCACHE_GETCMD" "spatchCache.getCmd") + +## Parse spatch()-like command-line for caching info +arg_sp= +arg_file= +args="$@" +spatch_opts() { + while test $# != 0 + do + arg_file="$1" + case "$1" in + --sp-file) + arg_sp="$2" + ;; + esac + shift + done +} +spatch_opts "$@" +if ! test -f "$arg_file" +then + arg_file= +fi + +hash_for_cache() { + # Parameters that should affect the cache + echo "args=$args" + echo "config spatchCache.spatch=$spatch" + echo "config spatchCache.debug=$debug" + echo "config spatchCache.trace=$trace" + echo "config spatchCache.cacheWhenStderr=$cacheWhenStderr" + echo + + # Our target file and its dependencies + git hash-object "$1" "$2" $(grep -E -o '^[^:]+:$' "$3" | tr -d ':') +} + +# Sanity checks +if ! test -f "$arg_sp" && ! test -f "$arg_file" +then + echo $0: no idea how to cache "$@" >&2 + exit 128 +fi + +# Main logic +dirname=$(dirname "$arg_file") +basename=$(basename "$arg_file") +eval "dep=$dependFormat" + +if ! test -f "$dep" +then + trace_it "$0: CANTCACHE have no '$dep' for '$arg_file'!" + exec "$spatch" "$@" +fi + +if test -n "$debug" +then + trace_it "$0: The full cache input for '$arg_sp' '$arg_file' '$dep'" + hash_for_cache "$arg_sp" "$arg_file" "$dep" >&2 +fi +sum=$(hash_for_cache "$arg_sp" "$arg_file" "$dep" | git hash-object --stdin) + +trace_it "$0: processing '$arg_file' with '$arg_sp' rule, and got hash '$sum' for it + '$dep'" + +getret= +if test -z "$get" +then + if test $(redis-cli SISMEMBER spatch-cache "$sum") = 1 + then + getret=0 + else + getret=1 + fi +else + $set "$sum" + getret=$? +fi + +if test "$getret" = 0 +then + trace_it "$0: HIT for '$arg_file' with '$arg_sp'" + exit 0 +else + trace_it "$0: MISS: for '$arg_file' with '$arg_sp'" +fi + +out="$(mktemp)" +err="$(mktemp)" + +set +e +"$spatch" "$@" >"$out" 2>>"$err" +ret=$? +cat "$out" +cat "$err" >&2 +set -e + +nocache= +if test $ret != 0 +then + nocache="exited non-zero: $ret" +elif test -s "$out" +then + nocache="had patch output" +elif test -z "$cacheWhenStderr" && test -s "$err" +then + nocache="had stderr (use --very-quiet or spatchCache.cacheWhenStderr=true?)" +fi + +if test -n "$nocache" +then + trace_it "$0: NOCACHE ($nocache): for '$arg_file' with '$arg_sp'" + exit "$ret" +fi + +trace_it "$0: SET: for '$arg_file' with '$arg_sp'" + +setret= +if test -z "$set" +then + if test $(redis-cli SADD spatch-cache "$sum") = 1 + then + setret=0 + else + setret=1 + fi +else + "$set" "$sum" + setret=$? +fi + +if test "$setret" != 0 +then + echo "FAILED to set '$sum' in cache!" >&2 + exit 128 +fi + +exit "$ret" -- cgit v1.2.3