C++ (Cpp) read_file_io_vec_pages Exemples

Exemple #1

Fichier : kernel_interface.cpp Projet : veer77/Haiku-services-branch

static status_t
fs_read_pages(fs_volume* _volume, fs_vnode* _node, void*  _cookie, off_t pos,
	const iovec* vecs, size_t count, size_t* _numBytes)
{
	iso9660_volume* volume = (iso9660_volume*)_volume->private_volume;
	iso9660_inode* node = (iso9660_inode*)_node->private_node;

	uint32 fileSize = node->dataLen[FS_DATA_FORMAT];
	size_t bytesLeft = *_numBytes;

	if (pos >= fileSize) {
		*_numBytes = 0;
		return B_OK;
	}
	if (pos + bytesLeft > fileSize) {
		bytesLeft = fileSize - pos;
		*_numBytes = bytesLeft;
	}

	file_io_vec fileVec;
	fileVec.offset = pos + node->startLBN[FS_DATA_FORMAT]
		* volume->logicalBlkSize[FS_DATA_FORMAT];
	fileVec.length = bytesLeft;

	uint32 vecIndex = 0;
	size_t vecOffset = 0;
	return read_file_io_vec_pages(volume->fd, &fileVec, 1, vecs, count,
		&vecIndex, &vecOffset, &bytesLeft);
}

Exemple #2

Fichier : kernel_interface.cpp Projet : DonCN/haiku

static status_t
btrfs_read_pages(fs_volume* _volume, fs_vnode* _node, void* _cookie,
	off_t pos, const iovec* vecs, size_t count, size_t* _numBytes)
{
	Volume* volume = (Volume*)_volume->private_volume;
	Inode* inode = (Inode*)_node->private_node;

	if (inode->FileCache() == NULL)
		return B_BAD_VALUE;

	rw_lock_read_lock(inode->Lock());

	uint32 vecIndex = 0;
	size_t vecOffset = 0;
	size_t bytesLeft = *_numBytes;
	status_t status;

	while (true) {
		file_io_vec fileVecs[8];
		size_t fileVecCount = 8;

		status = file_map_translate(inode->Map(), pos, bytesLeft, fileVecs,
			&fileVecCount, 0);
		if (status != B_OK && status != B_BUFFER_OVERFLOW)
			break;

		bool bufferOverflow = status == B_BUFFER_OVERFLOW;

		size_t bytes = bytesLeft;
		status = read_file_io_vec_pages(volume->Device(), fileVecs,
			fileVecCount, vecs, count, &vecIndex, &vecOffset, &bytes);
		if (status != B_OK || !bufferOverflow)
			break;

		pos += bytes;
		bytesLeft -= bytes;
	}

	rw_lock_read_unlock(inode->Lock());

	return status;
}