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//=============================================================================
/**
* @file Buffer_Stream_Test.cpp
*
* This program illustrates an implementation of the classic
* "bounded buffer" program using an ASX STREAM containing two
* Modules. Each ACE_Module contains two Tasks. Each ACE_Task
* contains a ACE_Message_Queue and a pointer to a
* ACE_Thread_Manager. Note how the use of these reusable
* components reduces the reliance on global variables.
*
* @author Prashant Jain <pjain@cs.wustl.edu> and Doug Schmidt <d.schmidt@vanderbilt.edu>
*/
//=============================================================================
#include "test_config.h"
#include "ace/Stream.h"
#include "ace/Module.h"
#include "ace/Task.h"
#include "ace/OS_NS_string.h"
#include "ace/OS_NS_time.h"
#if defined (ACE_HAS_THREADS)
static const char ACE_ALPHABET[] = "abcdefghijklmnopqrstuvwxyz";
typedef ACE_Stream<ACE_MT_SYNCH> MT_Stream;
typedef ACE_Module<ACE_MT_SYNCH> MT_Module;
typedef ACE_Task<ACE_MT_SYNCH> MT_Task;
/**
* @class Common_Task
*
* @brief Methods that are common to the Supplier and consumer.
*/
class Common_Task : public MT_Task
{
public:
Common_Task () {}
//FUZZ: disable check_for_lack_ACE_OS
// = ACE_Task hooks.
///FUZZ: enable check_for_lack_ACE_OS
virtual int open (void * = 0);
virtual int close (u_long = 0);
};
/**
* @class Supplier
*
* @brief Define the Supplier interface.
*/
class Supplier : public Common_Task
{
public:
Supplier () {}
/// Read data from stdin and pass to consumer.
virtual int svc ();
};
/**
* @class Consumer
*
* @brief Define the Consumer interface.
*/
class Consumer : public Common_Task
{
public:
Consumer () {}
/// Enqueue the message on the ACE_Message_Queue for subsequent
/// handling in the svc() method.
virtual int put (ACE_Message_Block *mb, ACE_Time_Value *tv = 0);
/// Receive message from Supplier and print to stdout.
virtual int svc ();
private:
/// Amount of time to wait for a timeout.
ACE_Time_Value timeout_;
};
// Spawn off a new thread.
int
Common_Task::open (void *)
{
if (this->activate (THR_NEW_LWP | THR_DETACHED) == -1)
ACE_ERROR_RETURN ((LM_ERROR, ACE_TEXT ("%p\n"), ACE_TEXT ("spawn")), -1);
return 0;
}
int
Common_Task::close (u_long exit_status)
{
ACE_DEBUG ((LM_DEBUG,
ACE_TEXT ("(%t) thread is exiting with status %d in module %s\n"),
exit_status,
this->name ()));
// Can do anything here that is required when a thread exits, e.g.,
// storing thread-specific information in some other storage
// location, etc.
return 0;
}
// The Supplier reads data from the stdin stream, creates a message,
// and then queues the message in the message list, where it is
// removed by the consumer thread. A 0-sized message is enqueued when
// there is no more data to read. The consumer uses this as a flag to
// know when to exit.
int
Supplier::svc ()
{
ACE_Message_Block *mb = 0;
// Send one message for each letter of the alphabet, then send an empty
// message to mark the end.
for (const char *c = ACE_ALPHABET; *c != '\0'; c++)
{
// Allocate a new message.
char d[2];
d[0] = *c;
d[1] = '\0';
ACE_NEW_RETURN (mb,
ACE_Message_Block (2),
-1);
ACE_OS::strcpy (mb->wr_ptr (), d);
mb->wr_ptr (2);
if (this->put_next (mb) == -1)
ACE_ERROR ((LM_ERROR, ACE_TEXT ("(%t) %p\n"),
ACE_TEXT ("put_next")));
}
ACE_NEW_RETURN(mb, ACE_Message_Block, -1);
if (this->put_next (mb) == -1)
ACE_ERROR ((LM_ERROR, ACE_TEXT ("(%t) %p\n"), ACE_TEXT ("put_next")));
return 0;
}
int
Consumer::put (ACE_Message_Block *mb, ACE_Time_Value *tv)
{
// Simply enqueue the Message_Block into the end of the queue.
return this->putq (mb, tv);
}
// The consumer dequeues a message from the ACE_Message_Queue, writes
// the message to the stderr stream, and deletes the message. The
// Consumer sends a 0-sized message to inform the consumer to stop
// reading and exit.
int
Consumer::svc ()
{
ACE_Message_Block *mb = 0;
int result;
const char *c = ACE_ALPHABET;
char *output = 0;
// Keep looping, reading a message out of the queue, until we
// timeout or get a message with a length == 0, which signals us to
// quit.
for (;;)
{
this->timeout_.set (ACE_OS::time (0) + 4, 0); // Wait for upto 4 seconds
result = this->getq (mb, &this->timeout_);
if (result == -1)
break;
size_t const length = mb->length ();
if (length > 0)
{
output = mb->rd_ptr ();
ACE_TEST_ASSERT (*c == output[0]);
c++;
}
mb->release ();
if (length == 0)
break;
}
ACE_TEST_ASSERT (result == 0 || errno == EWOULDBLOCK);
return 0;
}
#endif /* ACE_HAS_THREADS */
// Main driver function.
int
run_main (int, ACE_TCHAR *[])
{
ACE_START_TEST (ACE_TEXT ("Buffer_Stream_Test"));
#if defined (ACE_HAS_THREADS)
// Control hierachically-related active objects.
MT_Stream stream;
MT_Module *cm = 0;
MT_Module *sm = 0;
// Allocate the Consumer and Supplier modules.
ACE_NEW_RETURN (cm, MT_Module (ACE_TEXT ("Consumer"), new Consumer), -1);
ACE_NEW_RETURN (sm, MT_Module (ACE_TEXT ("Supplier"), new Supplier), -1);
// Create Supplier and Consumer Modules and push them onto the
// Stream. All processing is performed in the Stream.
if (stream.push (cm) == -1)
ACE_ERROR_RETURN ((LM_ERROR, ACE_TEXT ("%p\n"), ACE_TEXT ("push")), 1);
else if (stream.push (sm) == -1)
ACE_ERROR_RETURN ((LM_ERROR, ACE_TEXT ("%p\n"), ACE_TEXT ("push")), 1);
// Barrier synchronization: wait for the threads to exit, then exit
// ourselves.
ACE_Thread_Manager::instance ()->wait ();
#else
ACE_ERROR ((LM_INFO,
ACE_TEXT ("threads not supported on this platform\n")));
#endif /* ACE_HAS_THREADS */
ACE_END_TEST;
return 0;
}
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