Class: POSIX::Mqueue

Inherits:
Object
  • Object
show all
Defined in:
lib/posix/mqueue/version.rb,
ext/posix/mqueue.c

Constant Summary collapse

VERSION = 
"0.0.3"

Instance Method Summary collapse

Constructor Details

#initialize(queue) ⇒ Object 



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# File 'ext/posix/mqueue.c', line 127

VALUE posix_mqueue_initialize(VALUE self, VALUE queue)
{
  // TODO: Modify these options from initialize arguments
  // TODO: Set nonblock and handle error in #push
  struct mq_attr attr = {
    .mq_flags   = 0,          // Flags, 0 or O_NONBLOCK
    .mq_maxmsg  = 10,         // Max messages in queue
    .mq_msgsize = 4096,       // Max message size (bytes)
    .mq_curmsgs = 0           // # currently in queue
  };

  mqueue_t* data;
  TypedData_Get_Struct(self, mqueue_t, &mqueue_type, data);

  if (data->fd != -1) {
    // This would cause a memleak otherwise
    rb_raise(rb_eRuntimeError, "Illegal reinitialization");
  }

  data->attr = attr;
  data->queue_len = RSTRING_LEN(queue);
  data->queue = ruby_strdup(StringValueCStr(queue));
  data->fd = mq_open(data->queue, O_CREAT | O_RDWR, S_IRWXU | S_IRWXO | S_IRWXG, &data->attr);

  if (data->fd == (mqd_t)-1) {
    rb_sys_fail("Failed opening the message queue");
  }

  return self;
}

Instance Method Details

#receive ⇒ Object 



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# File 'ext/posix/mqueue.c', line 98

VALUE posix_mqueue_receive(VALUE self)
{
  int err;
  size_t buf_size;
  char *buf;
  VALUE str;

  mqueue_t* data;

  TypedData_Get_Struct(self, mqueue_t, &mqueue_type, data);

  buf_size = data->attr.mq_msgsize + 1;

  // Make sure the buffer is capable
  buf = (char*)malloc(buf_size);

  // TODO: Specify priority
  err = mq_receive(data->fd, buf, buf_size, NULL);

  if (err < 0) {
    rb_sys_fail("Message retrieval failed");
  }

  str = rb_str_new(buf, err);
  free(buf);

  return str;
}

#send(message) ⇒ Object 



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# File 'ext/posix/mqueue.c', line 77

VALUE posix_mqueue_send(VALUE self, VALUE message)
{
  int err;
  mqueue_t* data;

  TypedData_Get_Struct(self, mqueue_t, &mqueue_type, data);

  if (!RB_TYPE_P(message, T_STRING)) { 
    rb_raise(rb_eTypeError, "Message must be a string"); 
  }

  // TODO: Custom priority
  err = mq_send(data->fd, RSTRING_PTR(message), RSTRING_LEN(message), 10);

  if (err < 0) {
    rb_sys_fail("Message sending failed");
  }
  
  return Qtrue;
}

#unlink ⇒ Object 



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# File 'ext/posix/mqueue.c', line 64

VALUE posix_mqueue_unlink(VALUE self)
{
  mqueue_t* data;

  TypedData_Get_Struct(self, mqueue_t, &mqueue_type, data);

  if (mq_unlink(data->queue) == -1) {
    rb_sys_fail("Message queue unlinking failed");
  }

  return Qtrue;
}