From 759a20da421e4a049c7a22e4e9e791e5b82e8b94 Mon Sep 17 00:00:00 2001
From: Andy C <andy@chubot.org>
Date: Wed, 20 Jul 2016 09:31:04 -0700
Subject: [PATCH] Big build and test cleanup.

- Inline tests/Compare.* into tests/test.sh, and fix various issues,
  like assuming '.' is in the $PATH
- Add targets instrumented with LLVM sanitizers to the Makefile, and
  support running tests with them

TODO: Describe these changes in more detail in README, and add
instructions.
---
 Makefile                    | 190 ++++++++++++++++++++++++--------
 run.sh                      |  20 +++-
 test-results/2016-06-12.txt |  50 +++++++++
 tests/Compare.T             |  10 --
 tests/Compare.drek          |   2 +-
 tests/Compare.p             |  17 ---
 tests/Compare.t             |  17 ---
 tests/Compare.tt            |  49 ---------
 tests/REGRESS               |  21 ----
 tests/T.lilly               |  28 -----
 tests/ctimes                |   1 +
 tests/test.sh               | 211 ++++++++++++++++++++++++++++++++++++
 12 files changed, 426 insertions(+), 190 deletions(-)
 create mode 100644 test-results/2016-06-12.txt
 delete mode 100755 tests/Compare.T
 delete mode 100755 tests/Compare.p
 delete mode 100755 tests/Compare.t
 delete mode 100755 tests/Compare.tt
 delete mode 100755 tests/REGRESS
 delete mode 100755 tests/T.lilly
 create mode 100755 tests/test.sh

diff --git a/Makefile b/Makefile
index 8d52acb..c664ba1 100644
--- a/Makefile
+++ b/Makefile
@@ -22,68 +22,168 @@
 # THIS SOFTWARE.
 # ****************************************************************/
 
-CFLAGS = -g
-CFLAGS = -O2
-CFLAGS =
-
-CC = gcc -Wall -g -Wwrite-strings
-CC = gcc -fprofile-arcs -ftest-coverage # then gcov f1.c; cat f1.c.gcov
-CC = gcc -g -Wall -pedantic 
-CC = gcc -O4 -Wall -pedantic -fno-strict-aliasing
-
-YACC = bison -d -y
-#YACC = yacc -d -S
-#YFLAGS = -d -S
-		# -S uses sprintf in yacc parser instead of sprint
-
-OFILES = b.o main.o parse.o proctab.o tran.o lib.o run.o lex.o
-
-SOURCE = awk.h ytab.c ytab.h proto.h awkgram.y lex.c b.c main.c \
-	maketab.c parse.c lib.c run.c tran.c proctab.c 
-
-LISTING = awk.h proto.h awkgram.y lex.c b.c main.c maketab.c parse.c \
-	lib.c run.c tran.c 
+# CLANG_DIR should be set to build and run tests under sanitizers.
+ifdef CLANG_DIR
+	san_cc := $(CLANG_DIR)/bin/clang
+else
+	san_cc := clang
+endif
+
+# -d: produce a header file
+# -y: emulate POSIX yacc
+YFLAGS := -d -y
+
+obj_files := \
+	b.o \
+	main.o \
+	parse.o \
+	proctab.o \
+	tran.o \
+	lib.o \
+	run.o \
+	lex.o \
+	ytab.o
+
+default: bwk-dbg
+
+all: bwk bwk-dbg bwk-cov bwk-asan bwk-msan bwk-ubsan bwk-sancov-func test_bin
+
+test_bin: tests/echo tests/time
+
+HEADER_DEPS := awk.h ytab.h proto.h
+
+compile_c = $(CC) $(CFLAGS) -c -o $@ $<
+
+# TODO: Remove all this duplication.  Options:
+# - eval ?
+# - shell script to gen fragments, and then include?  Like .d fragments.
+
+# Compile objects
+_obj/bwk/%.o: %.c $(HEADER_DEPS)
+	mkdir -p _obj/bwk
+	$(compile_c)
+
+_obj/bwk-dbg/%.o: %.c $(HEADER_DEPS)
+	mkdir -p _obj/bwk-dbg
+	$(compile_c)
+
+_obj/bwk-cov/%.o: %.c $(HEADER_DEPS)
+	mkdir -p _obj/bwk-cov
+	$(compile_c)
+
+_obj/bwk-asan/%.o: %.c $(HEADER_DEPS)
+	mkdir -p _obj/bwk-asan
+	$(compile_c)
+
+_obj/bwk-msan/%.o: %.c $(HEADER_DEPS)
+	mkdir -p _obj/bwk-msan
+	$(compile_c)
+
+_obj/bwk-ubsan/%.o: %.c $(HEADER_DEPS)
+	mkdir -p _obj/bwk-ubsan
+	$(compile_c)
+
+_obj/bwk-sancov-func/%.o: %.c $(HEADER_DEPS)
+	mkdir -p _obj/bwk-sancov-func
+	$(compile_c)
+
+# NOTE: What is ALLOC used for?  Specify a different allocator, I guess.
+link_bwk = $(CC) -o $@ $(CFLAGS) $^ $(ALLOC) -lm
+
+# "release" target, stripped
+bwk: CFLAGS += -O4 -Wall -pedantic -fno-strict-aliasing
+bwk: $(addprefix _obj/bwk/,$(obj_files))
+	$(link_bwk)
+	strip bwk
+
+# "debug" target compiles faster
+bwk-dbg: CFLAGS += -Wall -pedantic 
+bwk-dbg: $(addprefix _obj/bwk-dbg/,$(obj_files))
+	$(link_bwk)
+
+# Build instrumented for coverage.
+# gcov f1.c; cat f1.c.gcov
+bwk-cov: CFLAGS += -fprofile-arcs -ftest-coverage
+bwk-cov: $(addprefix _obj/bwk-cov/,$(obj_files))
+	$(link_bwk)
+
+# Binaries built with Clang sanitizers.  All of these should be unstripped
+# because they show stack traces at runtime.
+bwk-asan: CC := $(san_cc)
+bwk-asan: CFLAGS += -fsanitize=address -g
+bwk-asan: $(addprefix _obj/bwk-asan/,$(obj_files))
+	$(link_bwk)
+
+bwk-msan: CC := $(san_cc)
+bwk-msan: CFLAGS += -fsanitize=memory -g
+bwk-msan: $(addprefix _obj/bwk-msan/,$(obj_files))
+	$(link_bwk)
+
+bwk-ubsan: CC := $(san_cc)
+bwk-ubsan: CFLAGS += -fsanitize=undefined -fno-omit-frame-pointer -g
+bwk-ubsan: $(addprefix _obj/bwk-ubsan/,$(obj_files))
+	$(link_bwk)
+
+# NOTES:
+# - Coverage works on top of top of sanitizers.  Just pick one I guess.
+# - There are different types of coverage, e.g. -fsanitize-coverage = func, bb
+#   or edge.  Picking one for now.
+bwk-sancov-func: CC := $(san_cc)
+bwk-sancov-func: CFLAGS += -fsanitize=memory -g -fsanitize-coverage=func
+bwk-sancov-func: $(addprefix _obj/bwk-sancov-func/,$(obj_files))
+	$(link_bwk)
+
+#
+# Code Generation
+#
+
+ytab.c ytab.h: awk.h proto.h awkgram.y
+	$(YACC) -o ytab.c $(YFLAGS) awkgram.y
+
+proctab.c: maketab
+	./maketab >proctab.c
 
-SHIP = README FIXES $(SOURCE) ytab[ch].bak makefile  \
-	 awk.1
+maketab: ytab.h maketab.c
+	$(CC) $(CFLAGS) maketab.c -o maketab
 
-a.out:	ytab.o $(OFILES)
-	$(CC) $(CFLAGS) ytab.o $(OFILES) $(ALLOC)  -lm
+#
+# Test utils
+#
 
-$(OFILES):	awk.h ytab.h proto.h
+tests/echo: tests/echo.c
+tests/time: tests/time.c
 
-ytab.o:	awk.h proto.h awkgram.y
-	$(YACC) $(YFLAGS) awkgram.y
-	mv y.tab.c ytab.c
-	mv y.tab.h ytab.h
-	$(CC) $(CFLAGS) -c ytab.c
+#
+# Release
+#
 
-proctab.c:	maketab
-	./maketab >proctab.c
+source := awk.h ytab.c ytab.h proto.h awkgram.y lex.c b.c main.c \
+	maketab.c parse.c lib.c run.c tran.c proctab.c 
 
-maketab:	ytab.h maketab.c
-	$(CC) $(CFLAGS) maketab.c -o maketab
+ship := README FIXES $(source) ytab[ch].bak makefile awk.1
 
 bundle:
 	@cp ytab.h ytabh.bak
 	@cp ytab.c ytabc.bak
-	@bundle $(SHIP)
+	@bundle $(ship)
 
 tar:
 	@cp ytab.h ytabh.bak
 	@cp ytab.c ytabc.bak
-	@bundle $(SHIP) >awk.shar
-	@tar cf awk.tar $(SHIP)
+	@bundle $(ship) >awk.shar
+	@tar cf awk.tar $(ship)
 	gzip awk.tar
 	ls -l awk.tar.gz
-	@zip awk.zip $(SHIP)
+	@zip awk.zip $(ship)
 	ls -l awk.zip
 
-names:
-	@echo $(LISTING)
-
 clean:
+	rm -r -f _obj
 	rm -f \
-		a.out *.o *.obj maketab \
-		*.bb *.bbg *.da *.gcov *.gcno *.gcda \
-		proctab.c ytab.c ytab.h
+		bwk bwk-* maketab \
+		*.bb *.bbg *.da \
+		proctab.c ytab.c ytab.h \
+		tests/echo tests/time
+
+.PHONY: clean
+.PHONY: bundle tar names
diff --git a/run.sh b/run.sh
index 1b0f000..5e1949b 100755
--- a/run.sh
+++ b/run.sh
@@ -9,8 +9,24 @@ set -o errexit
 
 download() {
   mkdir -p _tmp
-  wget --directory _tmp 'https://www.cs.princeton.edu/~bwk/btl.mirror/awk.tar.gz'
-  wget --directory _tmp 'https://www.cs.princeton.edu/~bwk/btl.mirror/awktest.a'
+  wget --directory _tmp \
+    'https://www.cs.princeton.edu/~bwk/btl.mirror/awk.tar.gz'
+  wget --directory _tmp \
+    'https://www.cs.princeton.edu/~bwk/btl.mirror/awktest.a'
+}
+
+count() {
+  ls *.[chy] | grep -v -E 'ytab|proctab' | xargs wc -l | sort -n
+}
+
+coverage() {
+  mkdir -p _gcov
+  rm --verbose _gcov/*
+
+  # After running tests with bwk-cov, .gcno and .gcda files are in
+  # obj/bwk-cov, next to the objects.
+  gcov --object-directory obj/bwk-cov/ *.c
+  mv *.gcov _gcov
 }
 
 "$@"
diff --git a/test-results/2016-06-12.txt b/test-results/2016-06-12.txt
new file mode 100644
index 0000000..c90f498
--- /dev/null
+++ b/test-results/2016-06-12.txt
@@ -0,0 +1,50 @@
+On Ubuntu 14.04, comparing against mawk.
+
+CPU: Intel(R) Core(TM) i7-4790 CPU @ 3.60GHz
+
+     new      old   new/old
+
+    0.08     0.02    4.000  tt.02:
+    0.08     0.03    2.667  tt.02a:
+    0.05     0.01    5.000  tt.03:
+    0.05     0.02    2.500  tt.03a:
+    0.25     0.11    2.273  tt.04:
+    0.27     0.10    2.700  tt.05:
+    0.06     0.02    3.000  tt.06:
+    0.05     0.02    2.500  tt.07:
+    0.09     0.04    2.250  tt.12:
+    0.87     0.12    7.250  tt.13:
+    1.10     0.22    5.000  tt.13a:
+    0.01     0.01    1.000  tt.14:
+    0.52     0.21    2.476  tt.15:
+    0.28     0.12    2.333  tt.16:
+    2.72     0.67    4.060  tt.big:
+
+    6.69     1.72
+
+avg new/old   = 2.334
+total new/old = 3.890
+21 tests
+
+     new      old   new/old
+
+    0.08     0.02    4.000  tt.02:
+    0.08     0.03    2.667  tt.02a:
+    0.05     0.02    2.500  tt.03:
+    0.05     0.02    2.500  tt.03a:
+    0.25     0.11    2.273  tt.04:
+    0.27     0.10    2.700  tt.05:
+    0.05     0.01    5.000  tt.06:
+    0.05     0.02    2.500  tt.07:
+    0.09     0.04    2.250  tt.12:
+    0.88     0.12    7.333  tt.13:
+    1.08     0.22    4.909  tt.13a:
+    0.52     0.20    2.600  tt.15:
+    0.29     0.13    2.231  tt.16:
+    2.70     0.67    4.030  tt.big:
+
+    6.64     1.71
+
+avg new/old   = 2.262
+total new/old = 3.883
+21 tests
diff --git a/tests/Compare.T b/tests/Compare.T
deleted file mode 100755
index 5c24867..0000000
--- a/tests/Compare.T
+++ /dev/null
@@ -1,10 +0,0 @@
-
-oldawk=${oldawk-awk}
-awk=${awk-../a.out}
-
-echo oldawk=$oldawk, awk=$awk
-
-for i in T.*
-do 
-	$i
-done
diff --git a/tests/Compare.drek b/tests/Compare.drek
index 9a3ff2d..1275332 100755
--- a/tests/Compare.drek
+++ b/tests/Compare.drek
@@ -32,4 +32,4 @@ do
 	cat foo1t foo2t >>footot
 done
 
-ctimes footot
+./ctimes footot
diff --git a/tests/Compare.p b/tests/Compare.p
deleted file mode 100755
index 487358d..0000000
--- a/tests/Compare.p
+++ /dev/null
@@ -1,17 +0,0 @@
-
-oldawk=${oldawk-awk}
-awk=${awk-../a.out}
-
-echo oldawk=$oldawk, awk=$awk
-
-for i
-do
-	echo "$i:"
-	$oldawk -f $i test.countries test.countries >foo1 
-	$awk -f $i test.countries test.countries >foo2 
-	if cmp -s foo1 foo2
-	then true
-	else echo -n "$i:	BAD ..."
-	fi
-	diff -b foo1 foo2 | sed -e 's/^/	/' -e 10q
-done
diff --git a/tests/Compare.t b/tests/Compare.t
deleted file mode 100755
index 6ba3704..0000000
--- a/tests/Compare.t
+++ /dev/null
@@ -1,17 +0,0 @@
-
-oldawk=${oldawk-myawk}
-awk=${awk-../a.out}
-
-echo oldawk=$oldawk, awk=$awk
-
-for i
-do
-	echo "$i:"
-	$oldawk -f $i test.data >foo1 
-	$awk -f $i test.data >foo2 
-	if cmp -s foo1 foo2
-	then true
-	else echo -n "$i:	BAD ..."
-	fi
-	diff -b foo1 foo2 | sed -e 's/^/	/' -e 10q
-done
diff --git a/tests/Compare.tt b/tests/Compare.tt
deleted file mode 100755
index ca828d2..0000000
--- a/tests/Compare.tt
+++ /dev/null
@@ -1,49 +0,0 @@
-#!/bin/sh
-
-oldawk=${oldawk-awk}
-awk=${awk-../a.out}
-
-echo compiling time.c
-gcc time.c -o time
-time=./time
-
-echo time command = $time
-
-#case `uname` in
-#SunOS)
-#	time=/usr/bin/time ;;
-#Linux)
-#	time=/usr/bin/time ;;
-#*)
-#	time=time ;;
-#esac
-
-echo oldawk = $oldawk, awk = $awk, time command = $time
-
-
-# an arbitrary collection of input data
-
-cat td.1 td.1 >foo.td
-sed 's/^........................//' td.1 >>foo.td
-pr -m td.1 td.1 td.1 >>foo.td
-pr -2 td.1 >>foo.td
-cat bib >>foo.td
-wc foo.td
-
-td=foo.td
->footot
-
-for i in $*
-do
-	echo $i "($oldawk vs $awk)":
-	# ind <$i
-	$time $oldawk -f $i $td >foo2 2>foo2t
-	cat foo2t
-	$time $awk -f $i $td >foo1 2>foo1t
-	cat foo1t
-	cmp foo1 foo2
-	echo $i: >>footot
-	cat foo1t foo2t >>footot
-done
-
-ctimes footot
diff --git a/tests/REGRESS b/tests/REGRESS
deleted file mode 100755
index 923f1cc..0000000
--- a/tests/REGRESS
+++ /dev/null
@@ -1,21 +0,0 @@
-#!/bin/sh
-
-uname -a
-gcc echo.c -o echo && echo echo compiled
-
-oldawk=${oldawk-awk}
-awk=${awk-../a.out}
-
-echo oldawk=$oldawk, awk=$awk 
-
-oldawk=$oldawk awk=$awk Compare.t t.*
-	echo `ls t.* | wc -l` tests; echo
-
-oldawk=$oldawk awk=$awk Compare.p p.? p.??*
-	echo `ls p.* | wc -l` tests; echo
-
-oldawk=$oldawk awk=$awk Compare.T
-	echo `grep '\$awk' T.* | wc -l` tests; echo
-
-oldawk=$oldawk awk=$awk Compare.tt tt.*
-	echo `ls tt.* | wc -l` tests; echo
diff --git a/tests/T.lilly b/tests/T.lilly
deleted file mode 100755
index 1a6b8b8..0000000
--- a/tests/T.lilly
+++ /dev/null
@@ -1,28 +0,0 @@
-echo T.lilly: miscellaneous RE tests from Bruce Lilly
-
-awk=${awk-../a.out}
-
-rm -f foo
-awk '
-/./ {
-	print $0 >"foo"
-	print "###", NR, $0
-	system("awk -f foo <\"lilly.ifile\" ")
-	close "foo"
-}' <lilly.progs >foo1 2>&1
-
-rm -f foo
-$awk '
-/./ {
-	print $0 >"foo"
-	print "###", NR, $0
-	system("../a.out -f foo <\"lilly.ifile\" ")
-	close "foo"
-}' <lilly.progs >foo2 2>&1
-
-echo `cat lilly.progs | wc -l` tests
-
-sed -e 's/awk://' -e 's/Syntax/syntax/' foo1 >glop1
-sed 's/..\/a.out://' foo2 >glop2
-diff glop1 glop2 >lilly.diff || echo 'bad: T.lilly is different'
-echo
diff --git a/tests/ctimes b/tests/ctimes
index 96ac465..294b9b5 100755
--- a/tests/ctimes
+++ b/tests/ctimes
@@ -1,3 +1,4 @@
+#!/bin/sh
 awk '
 BEGIN {
 	OFS = "\t"
diff --git a/tests/test.sh b/tests/test.sh
new file mode 100755
index 0000000..f847d3a
--- /dev/null
+++ b/tests/test.sh
@@ -0,0 +1,211 @@
+#!/bin/sh
+#
+# Test driver.
+#
+# TODO: Import busybox tests?  Need the "testing" framework.
+
+set -o nounset
+
+# TODO: share with run.sh/
+CLANG_DIR=~/install/clang+llvm-3.8.0-x86_64-linux-gnu-ubuntu-14.04
+# dash weirdness; ~ is not expanded unless we do it separately?
+# http://stackoverflow.com/questions/8441473/tilde-expansion-doesnt-work-when-i-logged-into-gui
+readonly CLANG_DIR
+readonly sym=$CLANG_DIR/bin/llvm-symbolizer
+
+# These are needed to show line numbers in stack traces.
+export ASAN_SYMBOLIZER_PATH=$sym
+export MSAN_SYMBOLIZER_PATH=$sym
+export UBSAN_SYMBOLIZER_PATH=$sym
+
+gcc echo.c -o echo && echo echo compiled
+
+# A constant that is used by all the tests.  Not changing this.
+readonly AWK=../a.out
+
+_print_header() {
+  local oldawk=$1
+  local newawk=$2
+
+  uname -a
+  echo "Comparing $newawk vs old $oldawk"
+}
+
+# ../a.out is hard-coded, so we have to use it
+_prepare_bin() {
+  local awk=$1
+
+  ( cd .. && make $awk test_bin )  # NOTE: pushd is not in /bin/sh
+
+  ln -s -f --verbose $awk ../a.out
+}
+
+setup() {
+  mkdir -p _tmp
+  ln -s -f --verbose /bin/busybox _tmp/awk
+}
+
+# We have the expected data
+golden() {
+  local awk=${1:-bwk}
+
+  _prepare_bin $awk
+
+  for i in T.*; do 
+    awk=$AWK ./$i
+  done
+  # TODO: Do the tests all use $awk, or a.out too?
+  echo "Ran $(grep '$awk' T.* | wc -l) test cases"
+  echo
+}
+
+# Wow, this exposes tons of divergences and bugs.
+# NOTE: Tests are not consistent because "BAD" is not always echoed to stderr!
+# Sometimes it goes to stdout.
+
+golden_all() {
+  #golden /usr/bin/mawk > _tmp/golden-mawk.log
+  golden /usr/bin/gawk > _tmp/golden-gawk.log
+  #golden _tmp/awk      > _tmp/golden-busybox.log
+
+  grep FAIL _tmp/golden-*.log
+}
+
+# Compare vs another version -- book examples
+compare_book() {
+  local oldawk=${1:-awk}
+  local newawk=${2:-bwk}
+
+  _print_header $oldawk $newawk
+  _prepare_bin $newawk
+
+  for i in p.*; do
+    echo "$i:"
+    $oldawk -f $i test.countries test.countries >foo1 
+    $AWK -f $i test.countries test.countries >foo2 
+    if ! cmp -s foo1 foo2; then
+      echo -n "$i: FAILED"
+    fi
+    diff -b foo1 foo2 | sed -e 's/^/	/' -e 10q
+  done
+
+  echo "Ran $(ls p.* | wc -l) test files"
+  echo
+}
+
+# A list of one line programs in lilly.progs, read from lilly.ifile
+compare_lilly() {
+  local oldawk=${1:-awk}
+  local newawk=${2:-bwk}
+
+  _print_header $oldawk $newawk
+  _prepare_bin $newawk
+
+  mkdir -p _tmp
+  local test_runner='
+/./ {
+  tmp = "_tmp/lilly_line"
+  print $0 > tmp
+  print "###", NR, $0
+  cmd = awk " -f " tmp " < lilly.ifile "
+  system(cmd)
+  close(tmp)
+}' 
+
+  # NOTE: Somehow './time' doesn't work here
+  awk -v awk=$oldawk "$test_runner" <lilly.progs >foo1 2>&1
+  awk -v awk=$AWK "$test_runner" <lilly.progs >foo2 2>&1
+
+  echo "Ran $(wc -l lilly.progs) lilly tests"
+
+  if ! diff foo1 foo2 >lilly.diff; then
+    echo 'FAILED: T.lilly, see lilly.diff'
+    cat lilly.diff
+  fi
+  echo
+}
+
+# Compare vs another version
+compare_t() {
+  local oldawk=${1:-awk}
+  local newawk=${2:-bwk}
+
+  _print_header $oldawk $newawk
+  _prepare_bin $newawk
+
+  for i in t.*; do
+    echo "$i:"
+    $oldawk -f $i test.data >foo1 
+    $AWK -f $i test.data >foo2 
+    if ! cmp -s foo1 foo2; then
+      echo -n "$i: FAILED"
+    fi
+    # indent the diff
+    diff -b foo1 foo2 | sed -e 's/^/	/' -e 10q
+  done
+
+  echo "Ran $(ls t.* | wc -l) test files"
+  echo
+}
+
+# Creates a file called foo.td
+_create_perf_data() {
+  cat td.1 td.1 >foo.td
+  sed 's/^........................//' td.1 >>foo.td
+  pr -m td.1 td.1 td.1 >>foo.td
+  pr -2 td.1 >>foo.td
+  cat bib >>foo.td
+  wc foo.td
+}
+
+# Perf tests on big data.
+#
+# TODO: Assert that a.out points to bwk, for speed?  Though when you run
+# coverage and ASAN, you don't want this.
+compare_perf() {
+  local oldawk=${1:-awk}
+  local newawk=${2:-bwk}
+
+  _print_header $oldawk $newawk
+  _prepare_bin $newawk
+
+  time=./time
+
+  _create_perf_data
+
+  # an arbitrary collection of input data
+  local td=foo.td
+  # Is this like touch?
+  >_tmp/perf_timing.log
+
+  for i in tt.*; do
+    echo $i "($oldawk vs $newawk)":
+    # ind <$i
+    $time $oldawk -f $i $td >foo2 2>foo2t
+    cat foo2t
+    $time $AWK -f $i $td >foo1 2>foo1t
+    cat foo1t
+    cmp foo1 foo2
+
+    # Accumulate timing
+    echo $i: >>_tmp/perf_timing.log
+    cat foo1t foo2t >>_tmp/perf_timing.log
+  done
+
+  ./ctimes _tmp/perf_timing.log
+
+  echo "Ran $(ls tt.* | wc -l) test files"
+  echo
+}
+
+# mawk < gawk < bwk < busybox awk in terms of running time.
+compare_perf_all() {
+  # TODO: Write reports to different files.
+  #compare_perf /usr/bin/mawk
+  #compare_perf /usr/bin/gawk
+
+  # busybox awk
+  compare_perf _tmp/awk
+}
+
+"$@"