Introduce HAS_LLSEEK.

[p5sagit/p5-mst-13.2.git] / t / lib / syslfs.t

# NOTE: this file tests how large files (>2GB) work with raw system IO.
# open(), tell(), seek(), print(), read() are tested in t/op/lfs.t.
# If you modify/add tests here, remember to update also t/op/lfs.t.

BEGIN {
	# Don't bother if there are no quads.
	eval { my $q = pack "q", 0 };
	if ($@) {
		print "1..0\n# no 64-bit types\n";
		exit(0);
	}
	chdir 't' if -d 't';
	unshift @INC, '../lib';
	require Config; import Config;
	# Don't bother if there are no quad offsets.
	if ($Config{lseeksize} < 8) {
		print "1..0\n# no 64-bit file offsets\n";
		exit(0);
	}
	require Fcntl; import Fcntl;
}

sub bye {
    close(BIG);
    unlink "big";
    exit(0);
}

# Known have-nots.
if ($^O eq 'win32' || $^O eq 'vms') {
    print "1..0\n# no sparse files\n";
    bye();
}

# Then try to deduce whether we have sparse files.

# We'll start off by creating a one megabyte file which has
# only three "true" bytes.  If we have sparseness, we should
# consume less blocks than one megabyte (assuming nobody has
# one megabyte blocks...)

my $O_LARGEFILE;
eval { $O_LARGEFILE = O_LARGEFILE };
$O_LARGEFILE = 0 unless defined $O_LARGEFILE;

sysopen(BIG, "big", O_WRONLY|O_CREAT|O_TRUNC|$O_LARGEFILE) or
	do { warn "sysopen failed: $!\n"; bye };
sysseek(BIG, 1_000_000, SEEK_SET);
syswrite(BIG, "big");
close(BIG);

my @s;

@s = stat("big");

print "# @s\n";

my $BLOCKSIZE = 512; # is this really correct everywhere?

unless (@s == 13 &&
	$s[7] == 1_000_003 &&
	defined $s[12] &&
	$BLOCKSIZE * $s[12] < 1_000_003) {
    print "1..0\n# no sparse files?\n";
    bye();
}

# By now we better be sure that we do have sparse files:
# if we are not, the following will hog 5 gigabytes of disk.  Ooops.

print "1..8\n";

my $fail = 0;

sysopen(BIG, "big", O_WRONLY|O_CREAT|O_TRUNC|$O_LARGEFILE) or
	do { warn "sysopen failed: $!\n"; bye };
sysseek(BIG, 5_000_000_000, SEEK_SET);
syswrite(BIG, "big");
close BIG;

@s = stat("big");

print "# @s\n";

sub fail () {
    print "not ";
    $fail++;
}

fail unless $s[7] == 5_000_000_003;	# exercizes pp_stat
print "ok 1\n";

fail unless -s "big" == 5_000_000_003;	# exercizes pp_ftsize
print "ok 2\n";

sysopen(BIG, "big", O_RDONLY) or do { warn "sysopen failed: $!\n"; bye };

sysseek(BIG, 4_500_000_000, SEEK_SET);

fail unless sysseek(BIG, 0, SEEK_CUR) == 4_500_000_000;
print "ok 3\n";

sysseek(BIG, 1, SEEK_CUR);

fail unless sysseek(BIG, 0, SEEK_CUR) == 4_500_000_001;
print "ok 4\n";

sysseek(BIG, -1, SEEK_CUR);

fail unless sysseek(BIG, 0, SEEK_CUR) == 4_500_000_000;
print "ok 5\n";

sysseek(BIG, -3, SEEK_END);

fail unless sysseek(BIG, 0, SEEK_CUR) == 5_000_000_000;
print "ok 6\n";

my $big;

fail unless sysread(BIG, $big, 3) == 3;
print "ok 7\n";

fail unless $big eq "big";
print "ok 8\n";

bye();

if ($fail) {
    print STDERR <<EOM;
#
# If the lfs (large file support) tests fail, it means that
# the *file system* you are running the tests on doesn't support
# large files (files larger than two gigabytes).  Perl may still
# be able to support such files, once you have such a file system.
#
EOM
}

# eof