tryfetch.cpp

一个很棒的网络控制系统仿真软件

#ifndef TRY_FETCH
#define TRY_FETCH

void* ttTryFetch(char* mailbox) {

  MailboxNode* mbn;
  Mailbox* m;
  void* msg;

  mbn = (MailboxNode*) rtsys->mailboxList->getFirst();
  while (mbn != NULL) {
    if (mbn->getMailbox()->name != NULL) {
      if (strcmp(mbn->getMailbox()->name, mailbox) == 0)
	break;
    }
    mbn = (MailboxNode*) mbn->getNext();
  }
    
  if (mbn == NULL) {
    // Mailbox does not exist 
    char buf[200];
    sprintf(buf, "ttTryFetch: Non-existent mailbox '%s'\n", mailbox);
    MEX_ERROR(buf);
    return NULL;
  }

  m = mbn->getMailbox();
  if (m->count == 0) {
    printf("ttTryFetch: Mailbox '%s' is empty\n", mailbox);
    msg = NULL;
  } else {
    msg = m->buffer[m->outP];
    m->buffer[m->outP] = NULL;
    m->count--;
    m->outP = (m->outP + 1) % m->maxSize;
  }  
  return msg;
}

int ttTryFetchMATLAB(char* mailbox) {

  MailboxNode* mbn;
  Mailbox* m;
  int value;

  mbn = (MailboxNode*) rtsys->mailboxList->getFirst();
  while (mbn != NULL) {
    if (mbn->getMailbox()->name != NULL) {
      if (strcmp(mbn->getMailbox()->name, mailbox) == 0)
	break;
    }
    mbn = (MailboxNode*) mbn->getNext();
  }
    
  if (mbn == NULL) {
    char buf[200];
    sprintf(buf, "ttTryFetch: Non-existent mailbox '%s'!", mailbox);
    MEX_ERROR(buf);
    return 0;
  }


  m = mbn->getMailbox();
  if (m->count == 0) {
    printf("ttTryFetch: Mailbox '%s' is empty\n", mailbox);
    value = 0;
  } else {
    m->count--;
    value = m->outP + 1;
    m->outP = (m->outP + 1) % m->maxSize;
  }  
  return value;
}

#endif