|
|
#!/bin/sh
# Experimental alternative to build2 that can run steps in parallel if their
# dependencies are met. Caveats:
#
# 1. We rely on the OS to schedule steps, so thousands of independent tasks
# will likely be counter-productive.
# 2. Can run out of virtual memory if you spawn too many say $CC processes.
# 3. Compilation errors can cause the script to hang. We tag the most common
# suspects with '|| quit', but can't eliminate the possibility entirely.
# 4. Ugly as heck! This version really benefits from comparisons with its
# 'upstream', build2. And even then, diff gets confused.
# 5. There's a mechanical difficulty: we use mktemp to reliably create
# temporary filenames, which has the side effect of also creating the
# files. So zero-size files are considered equivalent to non-existent
# files. When some commands have trouble with this (e.g. ar) we need to
# delete the empty file, which can expose us to a race condition wrt
# mktemp.
set -e # stop immediately on error
# Some environment variables that can be passed in. For example, to turn off
# optimization:
# $ CFLAGS=-g ./build4
test "$CXX" || export CXX=c++
test "$CC" || export CC=cc
test "$CFLAGS" || export CFLAGS="-g -O2"
export CFLAGS="$CFLAGS -Wall -Wextra -ftrapv -fno-strict-aliasing"
# Outline:
# [0-9]*.cc -> mu.cc -> .build/*.cc -> .build/*.o -> .build/mu_bin
# (layers) | | | |
# tangle cleave $CXX $CXX
# can also be called with a layer to only build until
# $ ./build4 --until 050
UNTIL_LAYER=${2:-zzz}
# there's two mechanisms for fast builds here:
# - if a command is quick to run, always run it but update the result only on any change
# - otherwise run it only if the output is 'older_than' the inputs
#
# avoid combining both mechanisms for a single file
# otherwise you'll see spurious messages about files being updated
# risk: a file may unnecessarily update without changes, causing unnecessary work downstream
# return 1 if $1 is older than _any_ of the remaining args
older_than() {
local target=$1
shift
if [ ! -s $target ]
then
#? echo "$target has size zero"
#? echo "updating $target" >&2
return 0 # success
fi
local f
for f in $*
do
if [ $f -nt $target ]
then
#? echo "updating $target" >&2
return 0 # success
fi
done
return 1 # failure
}
# redirect to $1, unless it's already identical
update() {
if [ ! -e $1 ]
then
cat > $1
else
cat > $1.tmp
diff -q $1 $1.tmp >/dev/null && rm $1.tmp || mv $1.tmp $1
fi
}
update_cp() {
if [ ! -e $2/$1 ]
then
cp $1 $2
elif [ $1 -nt $2/$1 ]
then
cp $1 $2
fi
}
noisy_cd() {
cd $1
echo "-- `pwd`" >&2
}
mv_if_exists() {
test -e $1 && mv $1 $2
return 0
}
# wait for all the given filenames to exist
# exit immediately if a special file called '.quit' exists
QUITFILE=`pwd`/.quit
rm -f $QUITFILE
wait_for_all() {
# could use inotify on Linux
while ! all_exist "$@"
do
#? echo waiting: $*
test -e $QUITFILE && return 1 # some step had an error; stop all waiting steps using errexit
sleep 1
done
return 0
}
quit() {
touch $QUITFILE
exit 1
}
all_exist() {
for f in "$@"
do
test -e $f || return 1
done
return 0
}
TMP=`mktemp`
mv_if_exists enumerate/enumerate $TMP
(
wait_for_all enumerate/enumerate.cc
older_than $TMP enumerate/enumerate.cc && {
echo "building enumerate"
$CXX $CFLAGS enumerate/enumerate.cc -o $TMP || quit
echo "done building enumerate"
}
mv $TMP enumerate/enumerate
) &
TMP=`mktemp`
mv_if_exists tangle/tangle $TMP
(
wait_for_all tangle/*.cc
older_than $TMP tangle/*.cc && {
echo "building tangle"
cd tangle
# auto-generate various lists (ending in '_list' by convention) {
# list of types
{
grep -h "^struct .* {" [0-9]*.cc |sed 's/\(struct *[^ ]*\).*/\1;/'
grep -h "^typedef " [0-9]*.cc
} |update type_list
# list of function declarations, so I can define them in any order
grep -h "^[^ #].*) {" [0-9]*.cc |sed 's/ {.*/;/' |update function_list
# list of code files to compile
ls [0-9]*.cc |grep -v "\.test\.cc$" |sed 's/.*/#include "&"/' |update file_list
# list of test files to compile
ls [0-9]*.test.cc |sed 's/.*/#include "&"/' |update test_file_list
# list of tests to run
grep -h "^[[:space:]]*void test_" [0-9]*.cc |sed 's/^\s*void \(.*\)() {$/\1,/' |update test_list
grep -h "^\s*void test_" [0-9]*.cc |sed 's/^\s*void \(.*\)() {.*/"\1",/' |update test_name_list
# }
# Now that we have all the _lists, compile 'tangle'
$CXX $CFLAGS boot.cc -o $TMP || quit
$TMP test
cd ..
echo "done building tangle"
}
mv $TMP tangle/tangle
) &
wait_for_all enumerate/enumerate
echo "enumerating layers"
LAYERS=$(./enumerate/enumerate --until $UNTIL_LAYER |grep '\.cc$')
echo "done enumerating layers"
TMP=`mktemp`
mv_if_exists mu.cc $TMP
(
wait_for_all $LAYERS enumerate/enumerate tangle/tangle
older_than $TMP $LAYERS enumerate/enumerate tangle/tangle && {
echo "running tangle"
# no update here; rely on 'update' calls downstream
./tangle/tangle $LAYERS >$TMP || quit
echo "done running tangle"
}
mv $TMP mu.cc
) &
TMP=`mktemp`
mv_if_exists cleave/cleave $TMP
(
wait_for_all cleave/cleave.cc
older_than $TMP cleave/cleave.cc && {
echo "building cleave"
$CXX $CFLAGS cleave/cleave.cc -o $TMP || quit
rm -rf .build
echo "done building cleave"
}
mv $TMP cleave/cleave
) &
wait_for_all mu.cc cleave/cleave # cleave/cleave just for the .build cleanup
mkdir -p .build
# auto-generate function declarations, so I can define them in any order
# functions start out unindented, have all args on the same line, and end in ') {'
#
# \/ ignore struct/class methods
grep -h "^[^[:space:]#].*) {$" mu.cc |grep -v ":.*(" |sed 's/ {.*/;/' |update .build/function_list
# auto-generate list of tests to run
grep -h "^\s*void test_" mu.cc |sed 's/^\s*void \(.*\)() {.*/\1,/' |update .build/test_list
grep -h "^\s*void test_" mu.cc |sed 's/^\s*void \(.*\)() {.*/"\1",/' |update .build/test_name_list
mkdir -p .build/termbox
update_cp termbox/termbox.h .build/termbox
TMP=`mktemp`
mv_if_exists mu_bin $TMP
(
wait_for_all mu.cc cleave/cleave termbox/*.c termbox/*.h termbox/*.inl
older_than $TMP mu.cc *_list cleave/cleave termbox/* && {
echo "building mu_bin"
./cleave/cleave mu.cc .build || quit
cd .build
# create the list of global variable declarations from the corresponding definitions
grep ';' global_definitions_list |sed 's/[=(].*/;/' |sed 's/^[^\/# ]/extern &/' |sed 's/^extern extern /extern /' |update global_declarations_list
for f in mu_*.cc
do
OBJ=`echo $f |sed 's/\.cc$/.o/'`
TMP=`mktemp`
mv_if_exists $OBJ $TMP
(
older_than $TMP $f header global_declarations_list function_list test_list && {
echo "building $OBJ"
$CXX $CFLAGS -c $f -o $TMP || quit
echo "done building $OBJ"
}
mv $TMP $OBJ
) &
done
cd ../termbox
TMP=`mktemp`
mv_if_exists utf8.o $TMP
(
older_than $TMP utf8.c && {
echo "building termbox/utf8.o"
$CC $CFLAGS -c utf8.c -o $TMP || quit
echo "done building termbox/utf8.o"
}
mv $TMP utf8.o
) &
TMP=`mktemp`
mv_if_exists termbox.o $TMP
(
older_than $TMP termbox.c termbox.h input.inl output.inl bytebuffer.inl && {
echo "building termbox/termbox.o"
$CC $CFLAGS -c termbox.c -o $TMP || quit
echo "done building termbox/termbox.o"
}
mv $TMP termbox.o
) &
TMP=`mktemp`
mv_if_exists libtermbox.a $TMP
(
wait_for_all termbox.o utf8.o
older_than $TMP termbox.o utf8.o && {
echo "building termbox/libtermbox.a"
rm $TMP; ar rcs $TMP termbox.o utf8.o || quit # race condition; later mktemp may end up reusing this file
echo "done building termbox/libtermbox.a"
}
mv $TMP libtermbox.a
) &
cd ..
MU_OBJS=`echo .build/mu_*.cc |sed 's/\.cc/.o/g'`
echo wait_for_all $MU_OBJS termbox/libtermbox.a
wait_for_all $MU_OBJS termbox/libtermbox.a
echo "building .build/mu_bin"
$CXX $CFLAGS $MU_OBJS termbox/libtermbox.a -o $TMP || quit
echo "done building .build/mu_bin"
echo "done building mu_bin"
}
mv $TMP mu_bin
) &
## [0-9]*.mu -> core.mu
wait_for_all enumerate/enumerate
echo "building core.mu"
MU_LAYERS=$(./enumerate/enumerate --until $UNTIL_LAYER |grep '\.mu$') || exit 0 # ok if no .mu files
cat $MU_LAYERS |update core.mu
echo "done building core.mu"
wait_for_all mu_bin
exit 0
# scenarios considered:
# 0 status when nothing needs updating
# only a single layer is recompiled when changing a C++ function
# stop immediately after any failure
|