#!/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
    pre { line-height: 125%; }
td.linenos .normal { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
span.linenos { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
td.linenos .special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
span.linenos.special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
.highlight .hll { background-color: #ffffcc }
.highlight .c { color: #888888 } /* Comment */
.highlight .err { color: #a61717; background-color: #e3d2d2 } /* Error */
.highlight .k { color: #008800; font-weight: bold } /* Keyword */
.highlight .ch { color: #888888 } /* Comment.Hashbang */
.highlight .cm { color: #888888 } /* Comment.Multiline */
.highlight .cp { color: #cc0000; font-weight: bold } /* Comment.Preproc */
.highlight .cpf { color: #888888 } /* Comment.PreprocFile */
.highlight .c1 { color: #888888 } /* Comment.Single */
.highlight .cs { color: #cc0000; font-weight: bold; background-color: #fff0f0 } /* Comment.Special */
.highlight .gd { color: #000000; background-color: #ffdddd } /* Generic.Deleted */
.highlight .ge { font-style: italic } /* Generic.Emph */
.highlight .ges { font-weight: bold; font-style: italic } /* Generic.EmphStrong */
.highlight .gr { color: #aa0000 } /* Generic.Error */
.highlight .gh { color: #333333 } /* Generic.Heading */
.highlight .gi { color: #000000; background-color: #ddffdd } /* Generic.Inserted */
.highlight .go { color: #888888 } /* Generic.Output */
.highlight .gp { color: #555555 } /* Generic.Prompt */
.highlight .gs { font-weight: bold } /* Generic.Strong */
.highlight .gu { color: #666666 } /* Generic.Subheading */
.highlight .gt { color: #aa0000 } /* Generic.Traceback */
.highlight .kc { color: #008800; font-weight: bold } /* Keyword.Constant */
.highlight .kd { color: #008800; font-weight: bold } /* Keyword.Declaration */
.highlight .kn { color: #008800; font-weight: bold } /* Keyword.Namespace */
.highlight .kp { color: #008800 } /* Keyword.Pseudo */
.highlight .kr { color: #008800; font-weight: bold } /* Keyword.Reserved */
.highlight .kt { color: #888888; font-weight: bold } /* Keyword.Type */
.highlight .m { color: #0000DD; font-weight: bold } /* Literal.Number */
.highlight .s { color: #dd2200; background-color: #fff0f0 } /* Literal.String */
.highlight .na { color: #336699 } /* Name.Attribute */
.highlight .nb { color: #003388 } /* Name.Builtin */
.highlight .nc { color: #bb0066; font-weight: bold } /* Name.Class */
.highlight .no { color: #003366; font-weight: bold } /* Name.Constant */
.highlight .nd { color: #555555 } /* Name.Decorator */
.highlight .ne { color: #bb0066; font-weight: bold } /* Name.Exception */
.highlight .nf { color: #0066bb; font-weight: bold } /* Name.Function */
.highlight .nl { color: #336699; font-style: italic } /* Name.Label */
.highlight .nn { color: #bb0066; font-weight: bold } /* Name.Namespace */
.highlight .py { color: #336699; font-weight: bold } /* Name.Property */
.highlight .nt { color: #bb0066; font-weight: bold } /* Name.Tag */
.highlight .nv { color: #336699 } /* Name.Variable */
.highlight .ow { color: #008800 } /* Operator.Word */
.highlight .w { color: #bbbbbb } /* Text.Whitespace */
.highlight .mb { color: #0000DD; font-weight: bold } /* Literal.Number.Bin */
.highlight .mf { color: #0000DD; font-weight: bold } /* Literal.Number.Float */
.highlight .mh { color: #0000DD; font-weight: bold } /* Literal.Number.Hex */
.highlight .mi { color: #0000DD; font-weight: bold } /* Literal.Number.Integer */
.highlight .mo { color: #0000DD; font-weight: bold } /* Literal.Number.Oct */
.highlight .sa { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Affix */
.highlight .sb { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Backtick */
.highlight .sc { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Char */
.highlight .dl { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Delimiter */
.highlight .sd { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Doc */
.highlight .s2 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Double */
.highlight .se { color: #0044dd; background-color: #fff0f0 } /* Literal.String.Escape */
.highlight .sh { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Heredoc */
.highlight .si { color: #3333bb; background-color: #fff0f0 } /* Literal.String.Interpol */
.highlight .sx { color: #22bb22; background-color: #f0fff0 } /* Literal.String.Other */
.highlight .sr { color: #008800; background-color: #fff0ff } /* Literal.String.Regex */
.highlight .s1 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Single */
.highlight .ss { color: #aa6600; background-color: #fff0f0 } /* Literal.String.Symbol */
.highlight .bp { color: #003388 } /* Name.Builtin.Pseudo */
.highlight .fm { color: #0066bb; font-weight: bold } /* Name.Function.Magic */
.highlight .vc { color: #336699 } /* Name.Variable.Class */
.highlight .vg { color: #dd7700 } /* Name.Variable.Global */
.highlight .vi { color: #3333bb } /* Name.Variable.Instance */
.highlight .vm { color: #336699 } /* Name.Variable.Magic */
.highlight .il { color: #0000DD; font-weight: bold } /* Literal.Number.Integer.Long */
#!/bin/sh
# Alternative to build0 that supports a --until flag to include only a subset
# of layers.
#   $ ./build1 --until 050
UNTIL_LAYER=${2:-zzz}

set -v
set -e  # stop immediately on error

# Some environment variables that can be passed in. For example, to turn off
# optimization:
#   $ CFLAGS=-g ./build1
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 -> mu_bin
# (layers)   |        |
#          tangle   $CXX

$CXX $CFLAGS enumerate/enumerate.cc -o enumerate/enumerate

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
  }  > type_list
  # list of function declarations, so I can define them in any order
  grep -h "^[^ #].*) {" [0-9]*.cc  |sed 's/ {.*/;/'  > function_list
  # list of code files to compile
  ls [0-9]*.cc  |grep -v "\.test\.cc$"  |sed 's/.*/#include "&"/'  > file_list
  # list of test files to compile
  ls [0-9]*.test.cc  |sed 's/.*/#include "&"/'  > test_file_list
  # list of tests to run
  grep -h "^[[:space:]]*void test_" [0-9]*.cc  |sed 's/^\s*void \(.*\)() {$/\1,/'  > test_list
  grep -h "^\s*void test_" [0-9]*.cc  |sed 's/^\s*void \(.*\)() {.*/"\1",/'  > test_name_list
  # }
  # Now that we have all the _lists, compile 'tangle'
  $CXX $CFLAGS boot.cc -o tangle
  ./tangle test
cd ..

cd termbox
  $CC $CFLAGS -c termbox.c
  $CC $CFLAGS -c utf8.c
  ar rcs libtermbox.a *.o
cd ..

LAYERS=$(./enumerate/enumerate --until $UNTIL_LAYER  |grep '\.cc$')
./tangle/tangle $LAYERS  > mu.cc
# auto-generate function declarations, so I can define them in any order
# functions start out unindented, have all args on the same line, and end in ') {'
#
#                                      \/ ignore methods
grep -h "^[^[:space:]#].*) {$" mu.cc  |grep -v ":.*("  |sed 's/ {.*/;/'  > function_list
# auto-generate list of tests to run
grep -h "^\s*void test_" mu.cc  |sed 's/^\s*void \(.*\)() {.*/\1,/'  > test_list
grep -h "^\s*void test_" mu.cc  |sed 's/^\s*void \(.*\)() {.*/"\1",/'  > test_name_list
$CXX $CFLAGS mu.cc termbox/libtermbox.a -o mu_bin

## [0-9]*.mu -> core.mu

MU_LAYERS=$(./enumerate/enumerate --until $UNTIL_LAYER  |grep '\.mu$') || exit 0  # ok if no .mu files
cat $MU_LAYERS  > core.mu




 
generated by cgit-pink 1.4.1-2-gfad0 (git 2.36.2.497.gbbea4dcf42) at 2024-11-17 20:34:50 +0000
 


"> $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