NAME

Devel::Malloc - Low-level memory operations for real-time inter-thread communication.

SYNOPSIS MALLOC

use warnings;
use strict;
use POSIX;
use POSIX::RT::Signal qw(sigwaitinfo sigqueue);
use Devel::Malloc;
use threads;

POSIX::sigprocmask(POSIX::SIG_BLOCK, POSIX::SigSet->new(&POSIX::SIGRTMIN));
my $thr = threads->create(\&_thread);

sub _thread
{
   my $sigset = POSIX::SigSet->new(&POSIX::SIGRTMIN);
   my $info=sigwaitinfo($sigset);
   my $str = _memget($info->{value}, 4);
   print $str."\n";
   _free($info->{value});
}

my $address = _malloc(4);
_memset($address, "TEST", 4);
sigqueue($$, &POSIX::SIGRTMIN, $address);
$thr->join();

SYNOPSIS ATOMIC

use Devel::Malloc;

# allocate mutex memory
my $mutex = _malloc(1);
if ($mutex)
{
   # mutex init
   __sync_and_and_fetch($mutex, 0, 1);

   for (1..10)
   {
       # lock mutex
       while (__sync_lock_test_and_set($mutex, 1, 1) == 1) { }

       # critical section here

       # unlock mutex
       __sync_lock_release($mutex, 1);
   }

   # free mutex memory
   _free($address);
}

DESCRIPTION

The _malloc() function allocates size bytes and returns memory address to the allocated memory. You can store bytes to memory using _memset() and retrieve them using _memget(). The _free() function deallocates memory.

Memory address returned by _malloc() can be used between threads.

Also you can store short byte arrays or unsigned integers using atomic opetaions.

For SV atomic operations $size must be from 1 to 8 (store/load). For IV atomic operations $size must be 1, 2, 4 or 8 if your sizeof(IV) == 8.

I hope you enjoyed it.

EXPORT GENERAL FUNCTIONS

$address = _malloc(size);

$address = _memset($address, $sv, $size = 0);

$sv = _memget($address, $size);

_free($address);

EXPORT ATOMIC FUCTIONS

__sync_store_sv($address, $sv, $size = 0)

$sv = __sync_load_sv($address, $size);

$iv = __sync_lock_test_and_set($address, $iv, $size);

$iv = __sync_lock_release($address, $size);

__sync_synchronize();

$iv = __sync_bool_compare_and_swap($address, $oldval, $newval, $size);

$iv = __sync_val_compare_and_swap($address, $oldval, $newval, $size);

$iv = __sync_add_and_fetch($address, $iv, $size);

$iv = __sync_sub_and_fetch($address, $iv, $size);

$iv = __sync_and_and_fetch($address, $iv, $size);

$iv = __sync_or_and_fetch($address, $iv, $size);

$iv = __sync_xor_and_fetch($address, $iv, $size);

$iv = __sync_nand_and_fetch($address, $iv, $size);

$iv = __sync_fetch_and_add($address, $iv, $size);

$iv = __sync_fetch_and_sub($address, $iv, $size);

$iv = __sync_fetch_and_and($address, $iv, $size);

$iv = __sync_fetch_and_or($address, $iv, $size);

$iv = __sync_fetch_and_xor($address, $iv, $size);

$iv = __sync_fetch_and_nand($address, $iv, $size);

AUTHOR

Yury Kotlyarov yura@cpan.org

SEE ALSO

POSIX::RT::Signal, POSIX, threads