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#!./perl
BEGIN {
chdir 't' if -d 't';
require './test.pl';
set_up_inc('../lib');
skip_all('Can\'t run under miniperl') if is_miniperl();
}
use strict;
use Fcntl qw(SEEK_SET SEEK_CUR SEEK_END); # Not 0, 1, 2 everywhere.
use Errno qw(EACCES);
plan(128);
my $fh;
my $var = "aaa\n";
ok(open($fh,"+<",\$var));
is(<$fh>, $var);
ok(eof($fh));
ok(seek($fh,0,SEEK_SET));
ok(!eof($fh));
ok(print $fh "bbb\n");
is($var, "bbb\n");
$var = "foo\nbar\n";
ok(seek($fh,0,SEEK_SET));
ok(!eof($fh));
is(<$fh>, "foo\n");
ok(close $fh, $!);
# Test that semantics are similar to normal file-based I/O
# Check that ">" clobbers the scalar
$var = "Something";
open $fh, ">", \$var;
is($var, "");
# Check that file offset set to beginning of scalar
my $off = tell($fh);
is($off, 0);
# Check that writes go where they should and update the offset
$var = "Something";
print $fh "Brea";
$off = tell($fh);
is($off, 4);
is($var, "Breathing");
close $fh;
# Check that ">>" appends to the scalar
$var = "Something ";
open $fh, ">>", \$var;
$off = tell($fh);
is($off, 10);
is($var, "Something ");
# Check that further writes go to the very end of the scalar
$var .= "else ";
is($var, "Something else ");
$off = tell($fh);
is($off, 10);
print $fh "is here";
is($var, "Something else is here");
close $fh;
# Check that updates to the scalar from elsewhere do not
# cause problems
$var = "line one\nline two\line three\n";
open $fh, "<", \$var;
while (<$fh>) {
$var = "foo";
}
close $fh;
is($var, "foo");
# Check that dup'ing the handle works
$var = '';
open $fh, "+>", \$var;
print $fh "xxx\n";
open my $dup,'+<&',$fh;
print $dup "yyy\n";
seek($dup,0,SEEK_SET);
is(<$dup>, "xxx\n");
is(<$dup>, "yyy\n");
close($fh);
close($dup);
open $fh, '<', \42;
is(<$fh>, "42", "reading from non-string scalars");
close $fh;
{ package P; sub TIESCALAR {bless{}} sub FETCH { "shazam" } sub STORE {} }
tie my $p, 'P'; open $fh, '<', \$p;
is(<$fh>, "shazam", "reading from magic scalars");
{
use warnings;
my $warn = 0;
local $SIG{__WARN__} = sub { $warn++ };
open my $fh, '>', \my $scalar;
print $fh "foo";
close $fh;
is($warn, 0, "no warnings when writing to an undefined scalar");
undef $scalar;
open $fh, '>>', \$scalar;
print $fh "oof";
close $fh;
is($warn, 0, "no warnings when appending to an undefined scalar");
}
{
use warnings;
my $warn = 0;
local $SIG{__WARN__} = sub { $warn++ };
for (1..2) {
open my $fh, '>', \my $scalar;
close $fh;
}
is($warn, 0, "no warnings when reusing a lexical");
}
{
use warnings;
my $warn = 0;
local $SIG{__WARN__} = sub { $warn++ };
my $fetch = 0;
{
package MgUndef;
sub TIESCALAR { bless [] }
sub FETCH { $fetch++; return undef }
sub STORE {}
}
tie my $scalar, 'MgUndef';
open my $fh, '<', \$scalar;
close $fh;
is($warn, 0, "no warnings reading a magical undef scalar");
is($fetch, 1, "FETCH only called once");
}
{
use warnings;
my $warn = 0;
local $SIG{__WARN__} = sub { $warn++ };
my $scalar = 3;
undef $scalar;
open my $fh, '<', \$scalar;
close $fh;
is($warn, 0, "no warnings reading an undef, allocated scalar");
}
my $data = "a non-empty PV";
$data = undef;
open(MEM, '<', \$data) or die "Fail: $!\n";
my $x = join '', <MEM>;
is($x, '');
{
# [perl #35929] verify that works with $/ (i.e. test PerlIOScalar_unread)
my $s = <<'EOF';
line A
line B
a third line
EOF
open(F, '<', \$s) or die "Could not open string as a file";
local $/ = "";
my $ln = <F>;
close F;
is($ln, $s, "[perl #35929]");
}
# [perl #40267] PerlIO::scalar doesn't respect readonly-ness
{
my $warn;
local $SIG{__WARN__} = sub { $warn = "@_" };
ok(!(defined open(F, '>', \undef)), "[perl #40267] - $!");
is($warn, undef, "no warning with warnings off");
close F;
use warnings 'layer';
undef $warn;
my $ro = \43;
ok(!(defined open(F, '>', $ro)), $!);
is($!+0, EACCES, "check we get a read-onlyish error code");
like($warn, qr/Modification of a read-only value attempted/,
"check we did warn");
close F;
# but we can read from it
ok(open(F, '<', $ro), $!);
is(<F>, 43);
close F;
}
{
# Check that we zero fill when needed when seeking,
# and that seeking negative off the string does not do bad things.
my $foo;
ok(open(F, '>', \$foo));
# Seeking forward should zero fill.
ok(seek(F, 50, SEEK_SET));
print F "x";
is(length($foo), 51);
like($foo, qr/^\0{50}x$/);
is(tell(F), 51);
ok(seek(F, 0, SEEK_SET));
is(length($foo), 51);
# Seeking forward again should zero fill but only the new bytes.
ok(seek(F, 100, SEEK_SET));
print F "y";
is(length($foo), 101);
like($foo, qr/^\0{50}x\0{49}y$/);
is(tell(F), 101);
# Seeking back and writing should not zero fill.
ok(seek(F, 75, SEEK_SET));
print F "z";
is(length($foo), 101);
like($foo, qr/^\0{50}x\0{24}z\0{24}y$/);
is(tell(F), 76);
# Seeking negative should not do funny business.
ok(!seek(F, -50, SEEK_SET), $!);
ok(seek(F, 0, SEEK_SET));
ok(!seek(F, -50, SEEK_CUR), $!);
ok(!seek(F, -150, SEEK_END), $!);
}
# RT #43789: should respect tied scalar
{
package TS;
my $s;
sub TIESCALAR { bless \my $x }
sub FETCH { $s .= ':F'; ${$_[0]} }
sub STORE { $s .= ":S($_[1])"; ${$_[0]} = $_[1] }
package main;
my $x;
$s = '';
tie $x, 'TS';
my $fh;
ok(open($fh, '>', \$x), 'open-write tied scalar');
$s .= ':O';
print($fh 'ABC');
$s .= ':P';
ok(seek($fh, 0, SEEK_SET));
$s .= ':SK';
print($fh 'DEF');
$s .= ':P';
ok(close($fh), 'close tied scalar - write');
is($s, ':F:S():O:F:S(ABC):P:SK:F:S(DEF):P', 'tied actions - write');
is($x, 'DEF', 'new value preserved');
$x = 'GHI';
$s = '';
ok(open($fh, '+<', \$x), 'open-read tied scalar');
$s .= ':O';
my $buf;
is(read($fh,$buf,2), 2, 'read1');
$s .= ':R';
is($buf, 'GH', 'buf1');
is(read($fh,$buf,2), 1, 'read2');
$s .= ':R';
is($buf, 'I', 'buf2');
is(read($fh,$buf,2), 0, 'read3');
$s .= ':R';
is($buf, '', 'buf3');
ok(close($fh), 'close tied scalar - read');
is($s, ':F:S(GHI):O:F:R:F:R:F:R', 'tied actions - read');
}
# [perl #78716] Seeking beyond the end of the string, then reading
{
my $str = '1234567890';
open my $strIn, '<', \$str;
seek $strIn, 15, 1;
is read($strIn, my $buffer, 5), 0,
'seek beyond end end of string followed by read';
}
# Writing to COW scalars and non-PVs
{
my $bovid = __PACKAGE__;
open my $handel, ">", \$bovid;
print $handel "the COW with the crumpled horn";
is $bovid, "the COW with the crumpled horn", 'writing to COW scalars';
package lrcg { use overload fallback => 1, '""'=>sub { 'chin' } }
seek $handel, 3, 0;
$bovid = bless [], lrcg::;
print $handel 'mney';
is $bovid, 'chimney', 'writing to refs';
seek $handel, 1, 0;
$bovid = 42; # still has a PV
print $handel 5;
is $bovid, 45, 'writing to numeric scalar';
seek $handel, 1, 0;
undef $bovid;
$bovid = 42; # just IOK
print $handel 5;
is $bovid, 45, 'writing to numeric scalar';
}
# [perl #92706]
{
open my $fh, "<", \(my $f=*f); seek $fh, 2,1;
pass 'seeking on a glob copy';
open my $fh, "<", \(my $f=*f); seek $fh, -2,2;
pass 'seeking on a glob copy from the end';
}
# [perl #108398]
sub has_trailing_nul(\$) {
my ($ref) = @_;
my $sv = B::svref_2object($ref);
return undef if !$sv->isa('B::PV');
my $cur = $sv->CUR;
my $len = $sv->LEN;
return 0 if $cur >= $len;
my $ptrlen = length(pack('P', ''));
my $ptrfmt
= $ptrlen == length(pack('J', 0)) ? 'J'
: $ptrlen == length(pack('I', 0)) ? 'I'
: die "Can't determine pointer format";
my $pv_addr = unpack $ptrfmt, pack 'P', $$ref;
my $trailing = unpack 'P', pack $ptrfmt, $pv_addr+$cur;
return $trailing eq "\0";
}
SKIP: {
if ($Config::Config{'extensions'} !~ m!\bB\b!) {
skip "no B", 4;
}
require B;
open my $fh, ">", \my $memfile or die $!;
print $fh "abc";
ok has_trailing_nul $memfile,
'write appends trailing null when growing string';
seek $fh, 0,SEEK_SET;
print $fh "abc";
ok has_trailing_nul $memfile,
'write appends trailing null when not growing string';
seek $fh, 200, SEEK_SET;
print $fh "abc";
ok has_trailing_nul $memfile,
'write appends null when growing string after seek past end';
open $fh, ">", \($memfile = "hello");
ok has_trailing_nul $memfile,
'initial truncation in ">" mode provides trailing null';
}
# [perl #112780] Cloning of in-memory handles
SKIP: {
skip "no threads", 2 if !$Config::Config{useithreads};
require threads;
my $str = '';
open my $fh, ">", \$str;
$str = 'a';
is scalar threads::async(sub { my $foo = $str; $foo })->join, "a",
'scalars behind in-memory handles are cloned properly';
print $fh "a";
is scalar threads::async(sub { print $fh "b"; $str })->join, "ab",
'printing to a cloned in-memory handle works';
}
# [perl #113764] Duping via >&= (broken by the fix for #112870)
{
open FILE, '>', \my $content or die "Couldn't open scalar filehandle";
open my $fh, ">&=FILE" or die "Couldn't open: $!";
print $fh "Foo-Bar\n";
close $fh;
close FILE;
is $content, "Foo-Bar\n", 'duping via >&=';
}
# [perl #109828] PerlIO::scalar does not handle UTF-8
my $byte_warning = "Strings with code points over 0xFF may not be mapped into in-memory file handles\n";
{
use Errno qw(EINVAL);
my @warnings;
local $SIG{__WARN__} = sub { push @warnings, "@_" };
my $content = "12\x{101}";
$! = 0;
ok(!open(my $fh, "<", \$content), "non-byte open should fail");
is(0+$!, EINVAL, "check \$! is updated");
is(@warnings, 0, "should be no warnings (yet)");
use warnings "utf8";
$! = 0;
ok(!open(my $fh, "<", \$content), "non byte open should fail (and warn)");
is(0+$!, EINVAL, "check \$! is updated even when we warn");
is(@warnings, 1, "should have warned");
is($warnings[0], $byte_warning, "should have warned");
@warnings = ();
$content = "12\xA1";
utf8::upgrade($content);
ok(open(my $fh, "<", \$content), "open upgraded scalar");
binmode $fh;
my $tmp;
is(read($fh, $tmp, 4), 3, "read should get the downgraded bytes");
is($tmp, "12\xA1", "check we got the expected bytes");
close $fh;
is(@warnings, 0, "should be no more warnings");
}
{ # changes after open
my $content = "abc";
ok(open(my $fh, "+<", \$content), "open a scalar");
binmode $fh;
my $tmp;
is(read($fh, $tmp, 1), 1, "basic read");
seek($fh, 1, SEEK_SET);
$content = "\xA1\xA2\xA3";
utf8::upgrade($content);
is(read($fh, $tmp, 1), 1, "read from post-open upgraded scalar");
is($tmp, "\xA2", "check we read the correct value");
seek($fh, 1, SEEK_SET);
$content = "\x{101}\x{102}\x{103}";
my @warnings;
local $SIG{__WARN__} = sub { push @warnings, "@_" };
$! = 0;
is(read($fh, $tmp, 1), undef, "read from scalar with >0xff chars");
is(0+$!, EINVAL, "check errno set correctly");
is(@warnings, 0, "should be no warnings (yet)");
use warnings "utf8";
seek($fh, 1, SEEK_SET);
is(read($fh, $tmp, 1), undef, "read from scalar with >0xff chars");
is(@warnings, 1, "check warnings");
is($warnings[0], $byte_warning, "check warnings");
select $fh; # make sure print fails rather tha buffers
$| = 1;
select STDERR;
no warnings "utf8";
@warnings = ();
$content = "\xA1\xA2\xA3";
utf8::upgrade($content);
seek($fh, 1, SEEK_SET);
ok((print $fh "A"), "print to an upgraded byte string");
seek($fh, 1, SEEK_SET);
is($content, "\xA1A\xA3", "check result");
$content = "\x{101}\x{102}\x{103}";
$! = 0;
ok(!(print $fh "B"), "write to an non-downgradable SV");
is(0+$!, EINVAL, "check errno set");
is(@warnings, 0, "should be no warning");
use warnings "utf8";
ok(!(print $fh "B"), "write to an non-downgradable SV (and warn)");
is(@warnings, 1, "check warnings");
is($warnings[0], $byte_warning, "check warnings");
}
# RT #119529: Reading refs should not loop
{
my $x = \42;
open my $fh, "<", \$x;
my $got = <$fh>; # this used to loop
like($got, qr/^SCALAR\(0x[0-9a-f]+\)$/, "ref to a ref");
is ref $x, "SCALAR", "target scalar is still a reference";
}
# Appending to refs
{
my $x = \42;
my $as_string = "$x";
open my $refh, ">>", \$x;
is ref $x, "SCALAR", 'still a ref after opening for appending';
print $refh "boo\n";
is $x, $as_string."boo\n", 'string gets appended to ref';
}
SKIP:
{ # [perl #123443]
skip "Can't seek over 4GB with a small off_t", 4
if $Config::Config{lseeksize} < 8;
my $buf0 = "hello";
open my $fh, "<", \$buf0 or die $!;
ok(seek($fh, 2**32, SEEK_SET), "seek to a large position");
is(read($fh, my $tmp, 1), 0, "read from a large offset");
is($tmp, "", "should have read nothing");
ok(eof($fh), "fh should be eof");
}
{
my $buf0 = "hello";
open my $fh, "<", \$buf0 or die $!;
ok(!seek($fh, -10, SEEK_CUR), "seek to negative position");
is(tell($fh), 0, "shouldn't change the position");
}
SKIP:
{ # write() beyond SSize_t limit
skip "Can't overflow SSize_t with Off_t", 2
if $Config::Config{lseeksize} <= $Config::Config{sizesize};
my $buf0 = "hello";
open my $fh, "+<", \$buf0 or die $!;
ok(seek($fh, 2**32, SEEK_SET), "seek to a large position");
select((select($fh), ++$|)[0]);
ok(!(print $fh "x"), "write to a large offset");
}