+#! /usr/bin/perl
+
+# Find the directory that contains the grading files.
+our ($GRADES_DIR);
+
+# Add our Perl library directory to the include path.
+BEGIN {
+ ($GRADES_DIR = $0) =~ s#/[^/]+$##;
+ -d $GRADES_DIR or die "$GRADES_DIR: stat: $!\n";
+ unshift @INC, "$GRADES_DIR/../lib";
+}
+
+use warnings;
+use strict;
+use POSIX;
+use Algorithm::Diff;
+use Getopt::Long;
+
+our ($verbose) = 0; # Verbosity of output
+our (@TESTS); # Tests to run.
+my ($clean) = 0;
+my ($grade) = 0;
+
+GetOptions ("v|verbose+" => \$verbose,
+ "h|help" => sub { usage (0) },
+ "t|test=s" => \@TESTS,
+ "c|clean" => \$clean,
+ "g|grade" => \$grade)
+ or die "Malformed command line; use --help for help.\n";
+die "Non-option argument not supported; use --help for help.\n"
+ if @ARGV > 0;
+
+sub usage {
+ my ($exitcode) = @_;
+ print "run-tests, for grading Pintos multiprogramming projects.\n\n";
+ print "Invoke from a directory containing a student tarball named by\n";
+ print "the submit script, e.g. username.Oct.12.04.20.04.09.tar.gz.\n";
+ print "In normal usage, no options are needed.\n\n";
+ print "Output is produced in tests.out and details.out.\n\n";
+ print "Options:\n";
+ print " -c, --clean Remove old output files before starting\n";
+ print " -t, --test=TEST Execute TEST only (allowed multiple times)\n";
+ print " -g, --grade Instead of running tests, compose grade.out\n";
+ print " -v, --verbose Print commands before executing them\n";
+ print " -h, --help Print this help message\n";
+ exit $exitcode;
+}
+
+# Default set of tests.
+@TESTS = qw (sm-create sm-full sm-seq-block sm-seq-random sm-random
+ grow-create grow-seq-sm grow-seq-lg grow-file-size grow-tell
+ grow-sparse grow-root-sm grow-root-lg grow-dir-lg grow-two-files
+ ) unless @TESTS > 0;
+
+our (%args);
+
+# Handle final grade mode.
+if ($grade) {
+ open (OUT, ">grade.out") or die "grade.out: create: $!\n";
+
+ open (GRADE, "<grade.txt") or die "grade.txt: open: $!\n";
+ while (<GRADE>) {
+ last if /^\s*$/;
+ print OUT;
+ }
+ close (GRADE);
+
+ my (@tests) = snarf ("tests.out");
+ my ($p_got, $p_pos) = $tests[0] =~ m%\((\d+)/(\d+)\)% or die;
+
+ my (@review) = snarf ("review.txt");
+ my ($part_lost) = (0, 0);
+ for (my ($i) = $#review; $i >= 0; $i--) {
+ local ($_) = $review[$i];
+ if (my ($loss) = /^\s*([-+]\d+)/) {
+ $part_lost += $loss;
+ } elsif (my ($out_of) = m%\[\[/(\d+)\]\]%) {
+ my ($got) = $out_of + $part_lost;
+ $got = 0 if $got < 0;
+ $review[$i] =~ s%\[\[/\d+\]\]%($got/$out_of)% or die;
+ $part_lost = 0;
+
+ $p_got += $got;
+ $p_pos += $out_of;
+ }
+ }
+ die "Lost points outside a section\n" if $part_lost;
+
+ for (my ($i) = 1; $i <= $#review; $i++) {
+ if ($review[$i] =~ /^-{3,}\s*$/ && $review[$i - 1] !~ /^\s*$/) {
+ $review[$i] = '-' x (length ($review[$i - 1]));
+ }
+ }
+
+ print OUT "\nOVERALL SCORE\n";
+ print OUT "-------------\n";
+ print OUT "$p_got points out of $p_pos total\n\n";
+
+ print OUT map ("$_\n", @tests), "\n";
+ print OUT map ("$_\n", @review), "\n";
+
+ print OUT "DETAILS\n";
+ print OUT "-------\n\n";
+ print OUT map ("$_\n", snarf ("details.out"));
+
+ exit 0;
+}
+
+if ($clean) {
+ # Verify that we're roughly in the correct directory
+ # before we go blasting away files.
+ choose_tarball ();
+
+ xsystem ("rm -rf output pintos", VERBOSE => 1);
+ xsystem ("rm -f details.out tests.out", VERBOSE => 1);
+}
+
+# Create output directory, if it doesn't already exist.
+-d ("output") || mkdir ("output") or die "output: mkdir: $!\n";
+
+# Extract submission.
+extract_tarball () if ! -d "pintos";
+
+# Compile submission.
+compile ();
+
+# Verify that the proper directory was submitted.
+-d "pintos/src/threads" or die "pintos/src/threads: stat: $!\n";
+
+# Run and grade the tests.
+our $test;
+our %result;
+our %details;
+our %extra;
+for $test (@TESTS) {
+ print "$test: ";
+ my ($result) = run_test ($test);
+ if ($result eq 'ok') {
+ $result = grade_test ($test);
+ $result =~ s/\n$//;
+ }
+ print "$result";
+ print " - with warnings" if $result eq 'ok' && defined $details{$test};
+ print "\n";
+
+ $result{$test} = $result;
+}
+
+# Write output.
+write_grades ();
+write_details ();
+\f
+sub choose_tarball {
+ my (@tarballs)
+ = grep (/^[a-z0-9]+\.[A-Za-z]+\.\d+\.\d+\.\d+\.\d+.\d+\.tar\.gz$/,
+ glob ("*.tar.gz"));
+ die "no pintos dir and no source tarball\n" if scalar (@tarballs) == 0;
+
+ # Sort tarballs in reverse order by time.
+ @tarballs = sort { ext_mdyHMS ($b) cmp ext_mdyHMS ($a) } @tarballs;
+
+ print "Multiple tarballs: choosing $tarballs[0]\n"
+ if scalar (@tarballs) > 1;
+ return $tarballs[0];
+}
+
+sub extract_tarball {
+ my ($tarball) = choose_tarball ();
+
+ mkdir "pintos" or die "pintos: mkdir: $!\n";
+ mkdir "pintos/src" or die "pintos: mkdir: $!\n";
+
+ print "Extracting $tarball...\n";
+ xsystem ("cd pintos/src && tar xzf ../../$tarball",
+ DIE => "extraction failed\n");
+
+ if (-e "fixme.sh") {
+ print "Running fixme.sh...\n";
+ xsystem ("sh -e fixme.sh", DIE => "fix script failed\n");
+ }
+
+ print "Patching...\n";
+ xsystem ("patch -fs pintos/src/lib/debug.c < $GRADES_DIR/panic.diff",
+ LOG => "patch",
+ DIE => "patch failed\n");
+
+ open (CONSTANTS, ">pintos/src/constants.h")
+ or die "constants.h: create: $!\n";
+ print CONSTANTS "#define THREAD_JOIN_IMPLEMENTED 1\n";
+ close CONSTANTS;
+}
+
+sub ext_mdyHMS {
+ my ($s) = @_;
+ my ($ms, $d, $y, $H, $M, $S) =
+ $s =~ /.([A-Za-z]+)\.(\d+)\.(\d+)\.(\d+)\.(\d+).(\d+)\.tar\.gz$/
+ or die;
+ my ($m) = index ("janfebmaraprmayjunjulaugsepoctnovdec", lc $ms) / 3
+ or die;
+ return sprintf "%02d-%02d-%02d %02d:%02d:%02d", $y, $m, $d, $H, $M, $S;
+}
+\f
+sub test_source {
+ my ($test) = @_;
+ my ($src) = "$GRADES_DIR/$test.c";
+ -e $src or die "$src: stat: $!\n";
+ return $src;
+}
+
+sub test_constants {
+ my ($defines) = "";
+ return $defines;
+ }
+
+sub run_test {
+ my ($test) = @_;
+
+ # Reuse older results if any
+ if (open (DONE, "<output/$test/done")) {
+ my ($status);
+ $status = <DONE>;
+ chomp $status;
+ close (DONE);
+ return $status;
+ }
+
+ # Really run the test.
+ my ($status) = really_run_test ($test);
+
+ # Save the results for later.
+ open (DONE, ">output/$test/done") or die "output/$test/done: create: $!\n";
+ print DONE "$status\n";
+ close (DONE);
+
+ return $status;
+}
+
+sub compile {
+ print "Compiling...\n";
+ xsystem ("cd pintos/src/vm && make", LOG => "make")
+ or return "compile error";
+}
+
+sub really_run_test {
+ # Need to run it.
+ # If there's residue from an earlier test, move it to .old.
+ # If there's already a .old, delete it.
+ xsystem ("rm -rf output/$test.old", VERBOSE => 1) if -d "output/$test.old";
+ rename "output/$test", "output/$test.old" or die "rename: $!\n"
+ if -d "output/$test";
+
+ # Make output directory.
+ mkdir "output/$test";
+ xsystem ("pintos make-disk output/$test/fs.dsk 2 >/dev/null 2>&1",
+ DIE => "failed to create file system disk");
+ xsystem ("pintos make-disk output/$test/swap.dsk 2 >/dev/null 2>&1",
+ DIE => "failed to create swap disk");
+
+ # Format disk, install test.
+ my ($pintos_base_cmd) =
+ "pintos "
+ . "--os-disk=pintos/src/vm/build/os.dsk "
+ . "--fs-disk=output/$test/fs.dsk "
+ . "--swap-disk=output/$test/swap.dsk "
+ . "-v";
+ unlink ("output/$test/fs.dsk", "output/$test/swap.dsk"),
+ return "format/put error"
+ if !xsystem ("$pintos_base_cmd put -f $GRADES_DIR/$test $test",
+ LOG => "$test/put", TIMEOUT => 60, EXPECT => 1);
+
+ # Run.
+ my ($timeout) = 60;
+ my ($testargs) = defined ($args{$test}) ? " $args{$test}" : "";
+ my ($result) =
+ xsystem ("$pintos_base_cmd run -q -ex \"$test$testargs\"",
+ LOG => "$test/run", TIMEOUT => $timeout, EXPECT => 1)
+ ? "ok" : "Bochs error";
+ unlink ("output/$test/fs.dsk", "output/$test/swap.dsk");
+ return $result;
+}
+
+sub grade_test {
+ my ($test) = @_;
+
+ my (@output) = snarf ("output/$test/run.out");
+
+ my ($grade_func) = "grade_$test";
+ $grade_func =~ s/-/_/g;
+ if (-e "$GRADES_DIR/$test.exp" && !defined (&$grade_func)) {
+ eval {
+ verify_common (@output);
+ compare_output ("$GRADES_DIR/$test.exp", @output);
+ }
+ } else {
+ eval "$grade_func (\@output)";
+ }
+ if ($@) {
+ die $@ if $@ =~ /at \S+ line \d+$/;
+ return $@;
+ }
+ return "ok";
+}
+\f
+sub grade_process_death {
+ my ($proc_name, @output) = @_;
+
+ verify_common (@output);
+ @output = get_core_output (@output);
+ die "First line of output is not `($proc_name) begin' message.\n"
+ if $output[0] ne "($proc_name) begin";
+ die "Output contains `FAIL' message.\n"
+ if grep (/FAIL/, @output);
+ die "Output contains spurious ($proc_name) message.\n"
+ if grep (/\($proc_name\)/, @output) > 1;
+}
+
+sub grade_pt_bad_addr {
+ grade_process_death ('pt-bad-addr', @_);
+}
+
+sub grade_pt_write_code {
+ grade_process_death ('pt-write-code', @_);
+}
+
+sub grade_mmap_unmap {
+ grade_process_death ('mmap-unmap', @_);
+}
+\f
+sub verify_common {
+ my (@output) = @_;
+
+ my (@assertion) = grep (/PANIC/, @output);
+ if (@assertion != 0) {
+ my ($details) = "Kernel panic:\n $assertion[0]\n";
+
+ my (@stack_line) = grep (/Call stack:/, @output);
+ if (@stack_line != 0) {
+ $details .= " $stack_line[0]\n\n";
+ $details .= "Translation of backtrace:\n";
+ my (@addrs) = $stack_line[0] =~ /Call stack:((?: 0x[0-9a-f]+)+)/;
+
+ my ($A2L);
+ if (`uname -m`
+ =~ /i.86|pentium.*|[pk][56]|nexgen|viac3|6x86|athlon.*/) {
+ $A2L = "addr2line";
+ } else {
+ $A2L = "i386-elf-addr2line";
+ }
+ open (A2L, "$A2L -fe pintos/src/vm/build/kernel.o @addrs|");
+ for (;;) {
+ my ($function, $line);
+ last unless defined ($function = <A2L>);
+ $line = <A2L>;
+ chomp $function;
+ chomp $line;
+ $details .= " $function ($line)\n";
+ }
+ }
+
+ if ($assertion[0] =~ /sec_no < d->capacity/) {
+ $details .= <<EOF;
+\nThis assertion commonly fails when accessing a file via
+an inode that has been closed and freed. Freeing an inode
+clears all its sector indexes to 0xcccccccc, which is not
+a valid sector number for disks smaller than about 1.6 TB.
+EOF
+ }
+
+ $extra{$test} = $details;
+ die "Kernel panic. Details at end of file.\n"
+ }
+
+ if (grep (/Pintos booting/, @output) > 1) {
+ my ($details);
+
+ $details = "Pintos spontaneously rebooted during this test.\n";
+ $details .= "This is most often due to unhandled page faults.\n";
+ $details .= "Here's the output from the initial boot through the\n";
+ $details .= "first reboot:\n\n";
+
+ my ($i) = 0;
+ local ($_);
+ for (@output) {
+ $details .= " $_\n";
+ last if /Pintos booting/ && ++$i > 1;
+ }
+ $details{$test} = $details;
+ die "Triple-fault caused spontaneous reboot(s). "
+ . "Details at end of file.\n";
+ }
+
+ die "No output at all\n" if @output == 0;
+ die "Didn't start up properly: no \"Pintos booting\" startup message\n"
+ if !grep (/Pintos booting with.*kB RAM\.\.\./, @output);
+ die "Didn't start up properly: no \"Boot complete\" startup message\n"
+ if !grep (/Boot complete/, @output);
+ die "Didn't shut down properly: no \"Timer: # ticks\" shutdown message\n"
+ if !grep (/Timer: \d+ ticks/, @output);
+ die "Didn't shut down properly: no \"Powering off\" shutdown message\n"
+ if !grep (/Powering off/, @output);
+}
+
+# Get @output without header or trailer.
+sub get_core_output {
+ my (@output) = @_;
+
+ our ($test);
+ my ($first);
+ for ($first = 0; $first <= $#output; $first++) {
+ $first++, last if $output[$first] =~ /^Executing '$test.*':$/;
+ }
+
+ my ($last);
+ for ($last = $#output; $last >= 0; $last--) {
+ $last--, last if $output[$last] =~ /^Timer: \d+ ticks$/;
+ }
+
+ if ($last < $first) {
+ my ($no_first) = $first > $#output;
+ my ($no_last) = $last < $#output;
+ die "Couldn't locate output.\n";
+ }
+
+ return @output[$first ... $last];
+}
+
+sub fix_exit_codes {
+ my (@output) = @_;
+
+ # Remove lines that look like exit codes.
+ # Exit codes are supposed to be printed in the form "process: exit(code)"
+ # but people get unfortunately creative with it.
+ for (my ($i) = 0; $i <= $#output; $i++) {
+ local ($_) = $output[$i];
+
+ my ($process, $code);
+ if ((($process, $code) = /^([-a-z0-9 ]+):.*[ \(](-?\d+)\b\)?$/)
+ || (($process, $code) = /^([-a-z0-9 ]+) exit\((-?\d+)\)$/)
+ || (($process, $code)
+ = /^([-a-z0-9 ]+) \(.*\): exit\((-?\d+)\)$/)
+ || (($process, $code) = /^([-a-z0-9 ]+):\( (-?\d+) \) $/)
+ || (($code, $process) = /^shell: exit\((-?\d+)\) \| ([-a-z0-9]+)/)
+ ) {
+ splice (@output, $i, 1);
+ $i--;
+ }
+ }
+
+ return @output;
+}
+
+sub compare_output {
+ my ($exp, @actual) = @_;
+ @actual = fix_exit_codes (get_core_output (map ("$_\n", @actual)));
+ die "Program produced no output.\n" if !@actual;
+
+ my ($details) = "";
+ $details .= "$test actual output:\n";
+ $details .= join ('', map (" $_", @actual));
+
+ my (@exp) = map ("$_\n", snarf ($exp));
+
+ my ($fuzzy_match) = 0;
+ while (@exp != 0) {
+ my (@expected);
+ while (@exp != 0) {
+ my ($s) = shift (@exp);
+ last if $s eq "--OR--\n";
+ push (@expected, $s);
+ }
+
+ $details .= "\n$test acceptable output:\n";
+ $details .= join ('', map (" $_", @expected));
+
+ # Check whether they're the same.
+ if ($#actual == $#expected) {
+ my ($eq) = 1;
+ for (my ($i) = 0; $i <= $#expected; $i++) {
+ $eq = 0 if $actual[$i] ne $expected[$i];
+ }
+ return if $eq;
+ }
+
+ # They differ. Output a diff.
+ my (@diff) = "";
+ my ($d) = Algorithm::Diff->new (\@expected, \@actual);
+ my ($not_fuzzy_match) = 0;
+ while ($d->Next ()) {
+ my ($ef, $el, $af, $al) = $d->Get (qw (min1 max1 min2 max2));
+ if ($d->Same ()) {
+ push (@diff, map (" $_", $d->Items (1)));
+ } else {
+ push (@diff, map ("- $_", $d->Items (1))) if $d->Items (1);
+ push (@diff, map ("+ $_", $d->Items (2))) if $d->Items (2);
+ if ($d->Items (1)
+ || grep (/\($test\)|exit\(-?\d+\)|dying due to|Page fault/,
+ $d->Items (2))) {
+ $not_fuzzy_match = 1;
+ }
+ }
+ }
+ $fuzzy_match = 1 if !$not_fuzzy_match;
+
+ $details .= "Differences in `diff -u' format:\n";
+ $details .= join ('', @diff);
+ $details .= "(This is considered a `fuzzy match'.)\n"
+ if !$not_fuzzy_match;
+ }
+
+ if ($fuzzy_match) {
+ $details =
+ "This test passed, but with extra, unexpected output.\n"
+ . "Please inspect your code to make sure that it does not\n"
+ . "produce output other than as specified in the project\n"
+ . "description.\n\n"
+ . "$details";
+ } else {
+ $details =
+ "This test failed because its output did not match any\n"
+ . "of the acceptable form(s).\n\n"
+ . "$details";
+ }
+
+ $details{$test} = $details;
+ die "Output differs from expected. Details at end of file.\n"
+ unless $fuzzy_match;
+}
+\f
+sub write_grades {
+ my (@summary) = snarf ("$GRADES_DIR/tests.txt");
+
+ my ($ploss) = 0;
+ my ($tloss) = 0;
+ my ($total) = 0;
+ my ($warnings) = 0;
+ for (my ($i) = 0; $i <= $#summary; $i++) {
+ local ($_) = $summary[$i];
+ if (my ($loss, $test) = /^ -(\d+) ([-a-zA-Z0-9]+):/) {
+ my ($result) = $result{$test} || "Not tested.";
+
+ if ($result eq 'ok') {
+ if (!defined $details{$test}) {
+ # Test successful and no warnings.
+ splice (@summary, $i, 1);
+ $i--;
+ } else {
+ # Test successful with warnings.
+ s/-(\d+) //;
+ $summary[$i] = $_;
+ splice (@summary, $i + 1, 0,
+ " Test passed with warnings. "
+ . "Details at end of file.");
+ $warnings++;
+ }
+ } else {
+ $ploss += $loss;
+ $tloss += $loss;
+ splice (@summary, $i + 1, 0,
+ map (" $_", split ("\n", $result)));
+ }
+ } elsif (my ($ptotal) = /^Score: \/(\d+)$/) {
+ $total += $ptotal;
+ $summary[$i] = "Score: " . ($ptotal - $ploss) . "/$ptotal";
+ splice (@summary, $i, 0, " All tests passed.")
+ if $ploss == 0 && !$warnings;
+ $ploss = 0;
+ $warnings = 0;
+ $i++;
+ }
+ }
+ my ($ts) = "(" . ($total - $tloss) . "/" . $total . ")";
+ $summary[0] =~ s/\[\[total\]\]/$ts/;
+
+ open (SUMMARY, ">tests.out");
+ print SUMMARY map ("$_\n", @summary);
+ close (SUMMARY);
+}
+
+sub write_details {
+ open (DETAILS, ">details.out");
+ my ($n) = 0;
+ for my $test (@TESTS) {
+ next if $result{$test} eq 'ok' && !defined $details{$test};
+
+ my ($details) = $details{$test};
+ next if !defined ($details) && ! -e "output/$test/run.out";
+
+ my ($banner);
+ if ($result{$test} ne 'ok') {
+ $banner = "$test failure details";
+ } else {
+ $banner = "$test warnings";
+ }
+
+ print DETAILS "\n" if $n++;
+ print DETAILS "--- $banner ", '-' x (50 - length ($banner));
+ print DETAILS "\n\n";
+
+ if (!defined $details) {
+ my (@output) = snarf ("output/$test/run.out");
+
+ # Print only the first in a series of recursing panics.
+ my ($panic) = 0;
+ for my $i (0...$#output) {
+ local ($_) = $output[$i];
+ if (/PANIC/ && $panic++ > 0) {
+ @output = @output[0...$i];
+ push (@output,
+ "[...details of recursive panic omitted...]");
+ last;
+ }
+ }
+ $details = "Output:\n\n" . join ('', map ("$_\n", @output));
+ }
+ print DETAILS $details;
+
+ print DETAILS "\n", "-" x 10, "\n\n$extra{$test}"
+ if defined $extra{$test};
+ }
+ close (DETAILS);
+
+}
+\f
+sub xsystem {
+ my ($command, %options) = @_;
+ print "$command\n" if $verbose || $options{VERBOSE};
+
+ my ($log) = $options{LOG};
+
+ my ($pid, $status);
+ eval {
+ local $SIG{ALRM} = sub { die "alarm\n" };
+ alarm $options{TIMEOUT} if defined $options{TIMEOUT};
+ $pid = fork;
+ die "fork: $!\n" if !defined $pid;
+ if (!$pid) {
+ if (defined $log) {
+ open (STDOUT, ">output/$log.out");
+ open (STDERR, ">output/$log.err");
+ }
+ exec ($command);
+ exit (-1);
+ }
+ waitpid ($pid, 0);
+ $status = $?;
+ alarm 0;
+ };
+
+ my ($ok);
+ if ($@) {
+ die unless $@ eq "alarm\n"; # propagate unexpected errors
+ print "Timed out: ";
+ for (my ($i) = 0; $i < 10; $i++) {
+ kill ('SIGTERM', $pid);
+ sleep (1);
+ my ($retval) = waitpid ($pid, WNOHANG);
+ last if $retval == $pid || $retval == -1;
+ print "Waiting for $pid to die" if $i == 0;
+ print ".";
+ }
+ $ok = 1;
+ } else {
+ if (WIFSIGNALED ($status)) {
+ my ($signal) = WTERMSIG ($status);
+ die "Interrupted\n" if $signal == SIGINT;
+ print "Child terminated with signal $signal\n";
+ }
+
+ my ($exp_status) = !defined ($options{EXPECT}) ? 0 : $options{EXPECT};
+ $ok = WIFEXITED ($status) && WEXITSTATUS ($status) == $exp_status;
+ }
+
+
+ if (!$ok && defined $options{DIE}) {
+ my ($msg) = $options{DIE};
+ if (defined ($log)) {
+ chomp ($msg);
+ $msg .= "; see output/$log.err and output/$log.out for details\n";
+ }
+ die $msg;
+ } elsif (defined ($log) && $ok) {
+ unlink ("output/$log.err");
+ }
+
+ return $ok;
+}
+
+sub snarf {
+ my ($file) = @_;
+ open (OUTPUT, $file) or die "$file: open: $!\n";
+ my (@lines) = <OUTPUT>;
+ chomp (@lines);
+ close (OUTPUT);
+ return wantarray ? @lines : join ('', map ("$_\n", @lines));
+}
+
+sub files_equal {
+ my ($a, $b) = @_;
+ my ($equal);
+ open (A, "<$a") or die "$a: open: $!\n";
+ open (B, "<$b") or die "$b: open: $!\n";
+ if (-s A != -s B) {
+ $equal = 0;
+ } else {
+ my ($sa, $sb);
+ for (;;) {
+ sysread (A, $sa, 1024);
+ sysread (B, $sb, 1024);
+ $equal = 0, last if $sa ne $sb;
+ $equal = 1, last if $sa eq '';
+ }
+ }
+ close (A);
+ close (B);
+ return $equal;
+}
+
+sub file_contains {
+ my ($file, $expected) = @_;
+ open (FILE, "<$file") or die "$file: open: $!\n";
+ my ($actual);
+ sysread (FILE, $actual, -s FILE);
+ my ($equal) = $actual eq $expected;
+ close (FILE);
+ return $equal;
+}
+
+sub number_lines {
+ my ($ln, $lines) = @_;
+ my ($out);
+ for my $line (@$lines) {
+ chomp $line;
+ $out .= sprintf "%4d %s\n", $ln++, $line;
+ }
+ return $out;
+}