C++ discard函数代码示例

/* Trim zero blocks of the beginning and end of the object. */
static int default_trim(int fd, uint64_t oid, const struct siocb *iocb,
			uint64_t *poffset, uint32_t *plen)
{
	trim_zero_blocks(iocb->buf, poffset, plen);

	if (iocb->offset < *poffset) {
		sd_debug("discard between %d, %ld, %" PRIx64, iocb->offset,
			 *poffset, oid);

		if (discard(fd, iocb->offset, *poffset) < 0)
			return -1;
	}

	if (*poffset + *plen < iocb->offset + iocb->length) {
		uint64_t end = iocb->offset + iocb->length;
		if (end == get_objsize(oid))
			/* This is necessary to punch the last block */
			end = round_up(end, BLOCK_SIZE);
		sd_debug("discard between %ld, %ld, %" PRIx64, *poffset + *plen,
			 end, oid);

		if (discard(fd, *poffset + *plen, end) < 0)
			return -1;
	}

	return 0;
}

const char * configstring (const char * file, const char * part, const char * item, const char * text) 

{
    FILE *fp;
    if (file && part && item) {
        if ((fp = fopen (file, "rb"))) {
            for (c = getc (fp); c != EOF; discard (fp)) {
                while (isblank (c)) {                
                    c = getc (fp);
                }
                if (c != '[') {
                    continue;
                }
                do {
                    c = getc (fp);
                }
                while (isblank (c));
                if (!compare (fp, part)) {
                    continue;
                }
                if (c != ']') {
                    continue;
                }
                for (discard (fp); (c != '[') && (c != EOF); discard (fp)) {
                    while (isblank (c)) {
                        c = getc (fp);
                    }
                    if (c == ';') {
                        continue;
                    }
                    if (!compare (fp, item)) {
                        continue;
                    }
                    if (c != '=') {
                        continue;
                    }
                    do {
                        c = getc (fp);
                    }
                    while (isblank (c));
                    collect (fp);
                    text = buffer;
                    break;
                }
                break;
            }
            fclose (fp);
        }
    }

    if (text) {
        text = strdup(text);
    }

    return text;
}

/*
  removes an element within the list
    
    data       data of the element to find
    data_size  size of data
//*/
int removeelement(const char* data, const unsigned int data_size)
{
  // checks
  if(NULL == data) return -1;

  // find and delete
  element_t* tmp = find(data, data_size);
  if(NULL == tmp){
    fprintf(stderr, "element \"%s\" not found in list\n", data);
    return -1;
  }

  // element was first
  if(tmp == first){

    // list only has one element
    if(first == last){
      // TODO use discard first.. reset elements
      return 0;
    }

    first = first->next;
    if(0 != discard(&tmp)){
      return -1;
    }
    tmp = NULL;
    return 0;
  }

  // get prev element
  element_t* prev = first;
  while(prev->next){
    if(prev->next == tmp){
      break;
    }
  }
  
  // next element
  element_t* next = prev->next;
  if(NULL == next){
    return removelastelement();
  }

  // unlink
  prev->next = next;

  // delete
  if(0 != discard(&tmp)){
    return -1;
  }

  return 0;
}

inline Checkpoint mpi_plain(
    MPI_Comm communicator,
    I&& integrand,
    std::vector<std::size_t> const& iteration_calls,
    Checkpoint chkpt = make_plain_chkpt<numeric_type_of<I>>(),
    Callback callback = mpi_callback<Checkpoint>()
) {
    using T = numeric_type_of<I>;

    int rank = 0;
    MPI_Comm_rank(communicator, &rank);
    int world = 0;
    MPI_Comm_size(communicator, &world);

    auto generator = chkpt.generator();

    std::vector<T> buffer;

    std::size_t const usage = integrand.dimensions() *
        random_number_usage<T, decltype (generator)>();

    // perform iterations
    for (auto calls : iteration_calls)
    {
        generator.discard(usage * discard_before(calls, rank, world));

        // the number of function calls for each MPI process
        std::size_t const sub_calls = (calls / world) +
            (static_cast <std::size_t> (rank) < (calls % world) ? 1 : 0);
        auto const result = plain_iteration(integrand, sub_calls, generator);

        generator.discard(usage * discard_after(calls, sub_calls, rank, world));

        auto const& new_result = allreduce_result(
            communicator,
            result,
            buffer,
            std::vector<T>(),
            calls
        );

        chkpt.add(new_result, generator);

        if (!callback(communicator, chkpt))
        {
            break;
        }
    }

    return chkpt;
}

/*
 * fall:
 *	Drop an item someplace around here.
 */
int
fall(struct linked_list *item, int pr)
{
	register struct object *obj ;
	register struct room *rp ;
	static coord fpos ;
	int ret;

	obj = (struct object *) ldata(item) ;
	rp = roomin(&hero);
	if (obj->o_flags & CANRETURN) {
	    add_pack(item, TRUE);
	    return TRUE;
	}
	else if (fallpos(&obj->o_pos, &fpos, TRUE)) {
		if (obj->o_flags & CANBURN && ntraps + 1 < MAXTRAPS + MAXTRAPS) {
		    mvaddch(fpos.y, fpos.x, FIRETRAP);
		    traps[ntraps].tr_type = FIRETRAP;
		    traps[ntraps].tr_flags = ISFOUND;
		    traps[ntraps].tr_show = FIRETRAP;
		    traps[ntraps].tr_pos.y = fpos.y;
		    traps[ntraps++].tr_pos.x = fpos.x;
		    if (rp != NULL)
			rp->r_flags &= ~ISDARK;
			discard(item);
			ret = FALSE;
		}
		else {
		    mvaddch(fpos.y, fpos.x, obj->o_type) ;
		    obj->o_pos = fpos ;
		    attach(lvl_obj, item) ;
			ret = TRUE;
		}
		if (rp != NULL &&
		    (!(rp->r_flags & ISDARK) ||
		    (rp->r_flags & HASFIRE))) {
			light(&hero) ;
			mvwaddch(cw, hero.y, hero.x, PLAYER) ;
		}
		return ret;
	}
	if (pr) {
		if (obj->o_type == WEAPON)
			addmsg("The %s", weaps[obj->o_which]);
		else
			addmsg(inv_name(obj, TRUE));
		msg(" vanishes as it hits the ground.");
	}
	discard(item) ;
	return FALSE;
}

int toplevel(pstate *state) {
    UNPACK_STATE();
    int found = 0;
    while(curr <= eof) {
        qscan3('{','[','#');
        switch(*curr) {
            case '{': discard(); found += new_dict(state); break;
            case '[': discard(); found += new_list(state); break;
            case '#': discard(); found ++; break;
            default:  discard(); // EOF
        }
    }
    return found;
}

void WriteMail::init()
{
    m_toolbar = new QToolBar(this);
    addToolBar(m_toolbar);
    m_widgetStack = new QStackedWidget(this);

    m_cancelAction = new QAction(Qtmail::icon("cancel"),tr("Close"),this);
    connect( m_cancelAction, SIGNAL(triggered()), this, SLOT(discard()) );
    addAction(m_cancelAction);

    m_draftAction = new QAction(Qtmail::icon("saveToDraft"),tr("Save in drafts"),this);
    connect( m_draftAction, SIGNAL(triggered()), this, SLOT(draft()) );
    m_draftAction->setWhatsThis( tr("Save this message as a draft.") );
    addAction(m_draftAction);

    m_sendAction = new QAction(Qtmail::icon("sendmail"),tr("Send"),this);
    connect( m_sendAction, SIGNAL(triggered()), this, SLOT(sendStage()) );
    m_sendAction->setWhatsThis( tr("Send the message.") );
    addAction(m_sendAction);

    m_accountSelection = new QComboBox(m_toolbar);
    connect( m_accountSelection, SIGNAL(currentIndexChanged(int)), this, SLOT(accountSelectionChanged(int)) );

    m_selectComposerWidget = new SelectComposerWidget(this);
    m_selectComposerWidget->setObjectName("selectComposer");
    connect(m_selectComposerWidget, SIGNAL(selected(QPair<QString,QMailMessage::MessageType>)),
            this, SLOT(composerSelected(QPair<QString,QMailMessage::MessageType>)));
    connect(m_selectComposerWidget, SIGNAL(cancel()), this, SLOT(discard()));
    m_widgetStack->addWidget(m_selectComposerWidget);

    setCentralWidget(m_widgetStack);

    QMenuBar* mainMenuBar = new QMenuBar();
    setMenuBar(mainMenuBar);

    QMenu* file = mainMenuBar->addMenu("File");
    file->addAction(m_sendAction);
    file->addAction(m_draftAction);
    file->addSeparator();
    file->addAction(m_cancelAction);

    m_toolbar->addAction(m_sendAction);
    m_toolbar->addAction(m_draftAction);
    m_toolbar->addWidget(m_accountSelection);
    m_toolbar->addSeparator();

    setWindowTitle(tr("Compose"));

    setGeometry(0,0,defaultWidth,defaultHeight);
}

void QQuickDialog::click(QPlatformDialogHelper::StandardButton button, QPlatformDialogHelper::ButtonRole role)
{
    setVisible(false);
    m_clickedButton = static_cast<StandardButton>(button);
    emit buttonClicked();
    switch (role) {
    case QPlatformDialogHelper::AcceptRole:
        emit accept();
        break;
    case QPlatformDialogHelper::RejectRole:
        emit reject();
        break;
    case QPlatformDialogHelper::DestructiveRole:
        emit discard();
        break;
    case QPlatformDialogHelper::HelpRole:
        emit help();
        break;
    case QPlatformDialogHelper::YesRole:
        emit yes();
        break;
    case QPlatformDialogHelper::NoRole:
        emit no();
        break;
    case QPlatformDialogHelper::ApplyRole:
        emit apply();
        break;
    case QPlatformDialogHelper::ResetRole:
        emit reset();
        break;
    default:
        qWarning("unhandled Dialog button %d with role %d", (int)button, (int)role);
    }
}

// This one puts some data inside the ring buffer.
void RingBuffer::put(AudioBuffer& buf)
{
    std::lock_guard<std::mutex> l(lock_);
    const size_t sample_num = buf.frames();
    const size_t buffer_size = buffer_.frames();
    if (buffer_size == 0)
        return;

    size_t len = putLength();
    if (buffer_size - len < sample_num)
        discard(sample_num);
    size_t toCopy = sample_num;

    // Add more channels if the input buffer holds more channels than the ring.
    if (buffer_.channels() < buf.channels())
        buffer_.setChannelNum(buf.channels());

    size_t in_pos = 0;
    size_t pos = endPos_;

    while (toCopy) {
        size_t block = toCopy;

        if (block > buffer_size - pos) // Wrap block around ring ?
            block = buffer_size - pos; // Fill in to the end of the buffer

        buffer_.copy(buf, block, in_pos, pos);
        in_pos += block;
        pos = (pos + block) % buffer_size;
        toCopy -= block;
    }

    endPos_ = pos;
    not_empty_.notify_all();
}

void
fall(struct linked_list *item, int pr)
{
    struct object *obj;
    struct room *rp;
    static coord fpos;

    obj = (struct object *) ldata(item);
    if (fallpos(&obj->o_pos, &fpos, TRUE))
    {
	mvaddrawch(fpos.y, fpos.x, obj->o_type);
	obj->o_pos = fpos;
	if ((rp = roomin(&hero)) != NULL && !(rp->r_flags & ISDARK))
	{
	    light(&hero);
	    mvwaddrawch(cw, hero.y, hero.x, PLAYER);
	}
	attach(lvl_obj, item);
	return;
    }
    if (pr)
        if (obj->o_type == WEAPON) /* BUGFUX: Identification trick */
            msg("Your %s vanishes as it hits the ground.", w_names[obj->o_which]);
        else
            msg("%s vanishes as it hits the ground.", inv_name(obj,TRUE));
    discard(item);
}

static int
type1crypt(i_ctx_t *i_ctx_p,
           int (*proc)(byte *, const byte *, uint, ushort *))
{
    os_ptr op = osp;
    crypt_state state;
    uint ssize;

    check_type(op[-2], t_integer);
    state = op[-2].value.intval;
    if (op[-2].value.intval != state)
        return_error(e_rangecheck);	/* state value was truncated */
    check_read_type(op[-1], t_string);
    check_write_type(*op, t_string);
    ssize = r_size(op - 1);
    if (r_size(op) < ssize)
        return_error(e_rangecheck);
    discard((*proc)(op->value.bytes, op[-1].value.const_bytes, ssize,
                    &state));	/* can't fail */
    op[-2].value.intval = state;
    op[-1] = *op;
    r_set_size(op - 1, ssize);
    pop(1);
    return 0;
}

void EditEnumerationDialog::updateCurrentItem()
{
    discard();
    auto const item = m_dialog->itemList->currentItem();
    if (item != nullptr)
        item->setText(m_dialog->currentItem->text());
}

/*
 * playhand:
 *	Do up one hand of the game
 */
int
playhand(bool mycrib)
{
	int deckpos;

	werase(Compwin);
	wrefresh(Compwin);
	werase(Tablewin);
	wrefresh(Tablewin);

	knownum = 0;
	deckpos = deal(mycrib);
	sorthand(chand, FULLHAND);
	sorthand(phand, FULLHAND);
	makeknown(chand, FULLHAND);
	prhand(phand, FULLHAND, Playwin, FALSE);
	discard(mycrib);
	if (cut(mycrib, deckpos))
		return TRUE;
	if (peg(mycrib))
		return TRUE;
	werase(Tablewin);
	wrefresh(Tablewin);
	if (score(mycrib))
		return TRUE;
	return FALSE;
}

/**
 * Destroy descriptor ring
 *
 * @v netfront		Netfront device
 * @v ring		Descriptor ring
 * @v discard		Method used to discard outstanding buffer, or NULL
 */
static void netfront_destroy_ring ( struct netfront_nic *netfront,
				    struct netfront_ring *ring,
				    void ( * discard ) ( struct io_buffer * ) ){
	struct xen_device *xendev = netfront->xendev;
	struct xen_hypervisor *xen = xendev->xen;
	struct io_buffer *iobuf;
	unsigned int id;

	/* Flush any outstanding buffers */
	while ( ! netfront_ring_is_empty ( ring ) ) {
		id = ring->ids[ ring->id_cons & ( ring->count - 1 ) ];
		iobuf = netfront_pull ( netfront, ring, id );
		if ( discard )
			discard ( iobuf );
	}

	/* Unpublish shared ring reference */
	netfront_rm ( netfront, ring->ref_key );

	/* Revoke access from shared ring */
	xengrant_invalidate ( xen, ring->ref );

	/* Free page */
	free_dma ( ring->sring.raw, PAGE_SIZE );
	ring->sring.raw = NULL;
}

void qore_program_private::del(ExceptionSink* xsink) {
   printd(5, "QoreProgram::del() pgm: %p (base_object: %d)\n", pgm, base_object);

   if (thr_init)
      thr_init->deref(xsink);

   if (base_object) {
      deleteThreadData(xsink);

      // delete thread local storage key
      delete thread_local_storage;
      base_object = false;
   }

   // have to delete global variables first because of destructors.
   // method call can be repeated
   qore_root_ns_private::clearData(*RootNS, xsink);

   // delete all global variables, class static vars and constants
   RootNS->deleteData(xsink);

   // delete defines
   for (dmap_t::iterator i = dmap.begin(), e = dmap.end(); i != e; ++i)
      discard(i->second, xsink);
   dmap.clear();

   // method call can be repeated
   sb.del();
   //printd(5, "QoreProgram::~QoreProgram() this: %p deleting root ns %p\n", this, RootNS);

   delete RootNS;
   RootNS = 0;
}