Skip to content

Commit

Permalink
Use atomic writes for rules
Browse files Browse the repository at this point in the history 
For POSIX-compliant filesystems and modern NFS this should avoid
garbled output from concurrent make executions.

Issue: #47
  • Loading branch information
@dspinellis
dspinellis committed Oct 4, 2019
1 parent 87af360 commit 7e9994d
Showing 1 changed file with 62 additions and 37 deletions.
99 changes: 62 additions & 37 deletions src/csmake.pl
View file
Original file line number Diff line number Diff line change
Expand Up @@ -339,7 +339,17 @@ sub spy
#
#
open(RULES, $rulesfile = ">>$ENV{CSCOUT_SPY_TMPDIR}/rules") || die "Unable to open $rulesfile: $!\n";
my $rulesfile = "$ENV{CSCOUT_SPY_TMPDIR}/rules";
open(RULES, '>>', $rulesfile) || die "Unable to open $rulesfile: $!\n";
# Disable buffering to avoid (for POSIX-compliant filesystems) garbled output
# from concurrent spy executions
my $ofh = select RULES;
$| = 1;
select $ofh;
# String to accumulate rules, so that they can be written with an atomic write
my $rules;
';
print OUT "\$debug = $debug;\n";
Expand Down Expand Up @@ -397,15 +407,18 @@ sub ancestor
@ofiles = @ARGV2;

if ($#ofiles >= 0) {
print RULES "BEGIN AR\n";
print RULES "CMDLINE $origline\n";
print RULES 'OUTAR ', robust_abs_path($archive), "\n";
$rules .= "BEGIN AR\n";
$rules .= "CMDLINE $origline\n";
$rules .= 'OUTAR ', robust_abs_path($archive), "\n";
for $ofile (@ofiles) {
print RULES "INOBJ " . abs_path($ofile) . "\n";
$rules .= "INOBJ " . abs_path($ofile) . "\n";
}
print RULES "END AR\n";
$rules .= "END AR\n";
}

print RULES $rules;
close(RULES);

# Finally, execute the real ar
print STDERR "Finally run ($real @ARGV))\n" if ($debug);
exit system(($real, @ARGV)) / 256;
Expand Down Expand Up @@ -528,20 +541,20 @@ sub ancestor

# Output compilation rules
for $cfile (@cfiles) {
print RULES "BEGIN COMPILE\n";
print RULES "CMDLINE $origline\n";
$rules .= "BEGIN COMPILE\n";
$rules .= "CMDLINE $origline\n";
for $if (@incfiles) {
print RULES "$if\n";
$rules .= "$if\n";
}
print RULES "INSRC " . abs_path($cfile) . "\n";
$rules .= "INSRC " . abs_path($cfile) . "\n";
if ($compile) {
if ($output) { # cc -c -o foo.o foo.c
print RULES "OUTOBJ " . robust_abs_path($output) . "\n";
$rules .= "OUTOBJ " . robust_abs_path($output) . "\n";
} else { # cc -c foo.c
my $coutput= $cfile;
$coutput =~ s/\.c$/.o/i;
$coutput =~ s,.*/,,;
print RULES "OUTOBJ " . robust_abs_path($coutput) . "\n";
$rules .= "OUTOBJ " . robust_abs_path($coutput) . "\n";
}
} else { # cc -o foo foo.c OR cc foo.c
# Implicit output file
Expand All @@ -550,42 +563,45 @@ sub ancestor
# will be always increasing across all programs.
my $ofile = '/tmp/csmake-ofile-' . tell(RULES) . '.o';
push(@implicit_ofiles, $ofile);
print RULES "OUTOBJ $ofile\n";
$rules .= "OUTOBJ $ofile\n";
}
print RULES join("\n", @incs), "\n";
print RULES join("\n", @defs), "\n";
print RULES "END COMPILE\n";
$rules .= join("\n", @incs), "\n";
$rules .= join("\n", @defs), "\n";
$rules .= "END COMPILE\n";
}

if (!$compile && !$depwrite && ($#ofiles >= 0 || $#implicit_ofiles >= 0)) {

print RULES "BEGIN LINK\n";
print RULES "CMDLINE $origline\n";
$rules .= "BEGIN LINK\n";
$rules .= "CMDLINE $origline\n";
if ($output) {
print RULES "OUTEXE $output\n";
$rules .= "OUTEXE $output\n";
} else {
print RULES "OUTEXE a.out\n";
$rules .= "OUTEXE a.out\n";
}
for $ofile (@ofiles) {
print RULES "INOBJ " . abs_path($ofile) . "\n";
$rules .= "INOBJ " . abs_path($ofile) . "\n";
}
for $ofile (@implicit_ofiles) {
print RULES "INOBJ $ofile\n";
$rules .= "INOBJ $ofile\n";
}
for $afile (@afiles) {
print RULES "INLIB " . abs_path($afile) . "\n";
$rules .= "INLIB " . abs_path($afile) . "\n";
}
for $libfile (@libs) {
for $ldir (@ldirs) {
if (-r ($try = "$ldir/lib$libfile.a")) {
print RULES "INLIB " . abs_path($try) . "\n";
$rules .= "INLIB " . abs_path($try) . "\n";
last;
}
}
}
print RULES "END LINK\n";
$rules .= "END LINK\n";
}

print RULES $rules;
close(RULES);

# Finally, execute the real gcc
print STDERR "Finally run ($real @ARGV))\n" if ($debug);
exit system(($real, @ARGV)) / 256;
Expand Down Expand Up @@ -643,30 +659,33 @@ sub abs_if_exists


if ($#ofiles >= 0 || $#afiles >= 0) {
print RULES "BEGIN LINK\n";
print RULES "CMDLINE $origline\n";
$rules .= "BEGIN LINK\n";
$rules .= "CMDLINE $origline\n";
if ($output) {
print RULES 'OUTEXE ' . robust_abs_path($output) . "\n";
$rules .= 'OUTEXE ' . robust_abs_path($output) . "\n";
} else {
print RULES 'OUTEXE ' . robust_abs_path('a.out') . "\n";
$rules .= 'OUTEXE ' . robust_abs_path('a.out') . "\n";
}
for $ofile (@ofiles) {
print RULES 'INOBJ ' . abs_path($ofile) . "\n";
$rules .= 'INOBJ ' . abs_path($ofile) . "\n";
}
for $afile (@afiles) {
print RULES 'INLIB ' . abs_path($afile) . "\n";
$rules .= 'INLIB ' . abs_path($afile) . "\n";
}
for $libfile (@libs) {
for $ldir (@ldirs) {
if (-r ($try = "$ldir/lib$libfile.a")) {
print RULES "INLIB " . abs_path($try) . "\n";
$rules .= "INLIB " . abs_path($try) . "\n";
last;
}
}
}
print RULES "END LINK\n";
$rules .= "END LINK\n";
}

print RULES $rules;
close(RULES);

# Finally, execute the real ld
print STDERR "Finally run ($real @ARGV))\n" if ($debug);
exit system(($real, @ARGV)) / 256;
Expand All @@ -690,16 +709,19 @@ sub abs_if_exists
shift @ARGV2;
}

print RULES "RENAMELINE $origline\n";
$rules .= "RENAMELINE $origline\n";
if ($#ARGV2 == 1) {
print RULES 'RENAME ' . abs_path($ARGV2[0]) . ' ' . robust_abs_path($ARGV2[1]) . "\n";
$rules .= 'RENAME ' . abs_path($ARGV2[0]) . ' ' . robust_abs_path($ARGV2[1]) . "\n";
} else {
$dir = pop(@ARGV2);
for $f (@ARGV2) {
print RULES 'RENAME ' . abs_path($f) . ' ' . robust_abs_path("$dir/$f") . "\n";
$rules .= 'RENAME ' . abs_path($f) . ' ' . robust_abs_path("$dir/$f") . "\n";
}
}

print RULES $rules;
close(RULES);

# Finally, execute the real mv
print STDERR "Finally run ($real @ARGV))\n" if ($debug);
exit system(($real, @ARGV)) / 256;
Expand Down Expand Up @@ -752,10 +774,13 @@ sub abs_if_exists

if (@excecutables) {
foreach (@excecutables) {
print RULES "INSTALL $_ $dest\n";
$rules .= "INSTALL $_ $dest\n";
}
}

print RULES $rules;
close(RULES);

# Finally, execute the real install
print STDERR "Finally run ($real @ARGV))\n" if ($debug);
exit system(($real, @ARGV)) / 256;
Expand Down

0 comments on commit 7e9994d

Please sign in to comment.