C++ KPartition类代码示例

partition_id
_user_find_partition(const char *_filename, size_t *neededSize)
{
	UserStringParameter<false> filename;
	status_t error = filename.Init(_filename, B_PATH_NAME_LENGTH);
	if (error != B_OK)
		return error;

	KDiskDeviceManager *manager = KDiskDeviceManager::Default();
	// find the partition
	KPartition *partition = manager->RegisterPartition(filename);
	if (partition == NULL)
		return B_ENTRY_NOT_FOUND;
	PartitionRegistrar _(partition, true);
	partition_id id = partition->ID();
	if (neededSize != NULL) {
		// get and lock the partition's device
		KDiskDevice *device = manager->RegisterDevice(partition->ID(), false);
		if (device == NULL)
			return B_ENTRY_NOT_FOUND;
		PartitionRegistrar _2(device, true);
		if (DeviceReadLocker locker = device) {
			// get the needed size
			UserDataWriter writer;
			device->WriteUserData(writer);
			error = copy_to_user_value(neededSize, writer.AllocatedSize());
			if (error != B_OK)
				return error;
		} else
			return B_ERROR;
	}
	return id;
}

status_t
_user_set_partition_content_name(partition_id partitionID,
	int32* _changeCounter, const char* _name)
{
	// copy parameters in
	UserStringParameter<true> name;
	int32 changeCounter;

	status_t error = name.Init(_name, B_DISK_DEVICE_NAME_LENGTH);
	if (error == B_OK)
		error = copy_from_user_value(changeCounter, _changeCounter);
	if (error != B_OK)
		return error;

	// get the partition
	KDiskDeviceManager* manager = KDiskDeviceManager::Default();
	KPartition* partition = manager->WriteLockPartition(partitionID);
	if (partition == NULL)
		return B_ENTRY_NOT_FOUND;

	PartitionRegistrar registrar1(partition, true);
	PartitionRegistrar registrar2(partition->Device(), true);
	DeviceWriteLocker locker(partition->Device(), true);

	// check change counter
	if (changeCounter != partition->ChangeCounter())
		return B_BAD_VALUE;

	// the partition must be initialized
	KDiskSystem* diskSystem = partition->DiskSystem();
	if (diskSystem == NULL)
		return B_BAD_VALUE;

	// mark the partition busy and unlock
	if (!partition->CheckAndMarkBusy(false))
		return B_BUSY;
	locker.Unlock();

	// set content parameters
	error = diskSystem->SetContentName(partition, name.value, DUMMY_JOB_ID);

	// re-lock and unmark busy
	locker.Lock();
	partition->UnmarkBusy(false);

	if (error != B_OK)
		return error;

	// return change counter
	return copy_to_user_value(_changeCounter, partition->ChangeCounter());
}

status_t
_user_move_partition(partition_id partitionID, int32* changeCounter,
	partition_id childID, int32* childChangeCounter, off_t newOffset,
	partition_id* descendantIDs, int32* descendantChangeCounters,
	int32 descendantCount)
{
#if 0
	KDiskDeviceManager *manager = KDiskDeviceManager::Default();
	// get the partition
	KPartition *partition = manager->WriteLockPartition(partitionID);
	if (!partition)
		return B_ENTRY_NOT_FOUND;
	PartitionRegistrar registrar1(partition, true);
	PartitionRegistrar registrar2(partition->Device(), true);
	DeviceWriteLocker locker(partition->Device(), true);
	// check the new offset
	if (newOffset == partition->Offset())
		return B_OK;
	off_t proposedOffset = newOffset;
	status_t error = validate_move_partition(partition, changeCounter,
		&proposedOffset, true);
	if (error != B_OK)
		return error;
	if (proposedOffset != newOffset)
		return B_BAD_VALUE;
	// new offset is fine -- move the thing
	off_t moveBy = newOffset - partition->Offset();
	move_descendants(partition, moveBy);
	partition->Changed(B_PARTITION_CHANGED_OFFSET);
	// implicit partitioning system changes
	error = partition->Parent()->DiskSystem()->ShadowPartitionChanged(
		partition->Parent(), partition, B_PARTITION_MOVE_CHILD);
	if (error != B_OK)
		return error;
	// implicit descendants' content disk system changes
	return move_descendants_contents(partition);
#endif
return B_BAD_VALUE;
}

/*!	The system was booted from CD - prefer CDs over other entries. If there
	is no CD, fall back to the standard mechanism (as implemented by
	compare_image_boot().
*/
static int
compare_cd_boot(const void* _a, const void* _b)
{
	KPartition* a = *(KPartition**)_a;
	KPartition* b = *(KPartition**)_b;

	bool aIsCD = a->Type() != NULL
		&& !strcmp(a->Type(), kPartitionTypeDataSession);
	bool bIsCD = b->Type() != NULL
		&& !strcmp(b->Type(), kPartitionTypeDataSession);

	int compare = (int)aIsCD - (int)bIsCD;
	if (compare != 0)
		return compare;

	return compare_image_boot(_a, _b);
}

/*!	No image was chosen - prefer disks with names like "Antares", or "System"
 */
int
compare_image_boot(const void* _a, const void* _b)
{
	KPartition* a = *(KPartition**)_a;
	KPartition* b = *(KPartition**)_b;

	if (a->ContentName() != NULL) {
		if (b->ContentName() == NULL)
			return 1;
	} else if (b->ContentName() != NULL) {
		return -1;
	} else
		return 0;

	int compare = strcmp(a->ContentName(), b->ContentName());
	if (!compare)
		return 0;

	if (!strcasecmp(a->ContentName(), "Antares"))
		return 1;
	if (!strcasecmp(b->ContentName(), "Antares"))
		return -1;
	if (!strncmp(a->ContentName(), "System", 6))
		return 1;
	if (!strncmp(b->ContentName(), "System", 6))
		return -1;

	return compare;
}

void
vfs_mount_boot_file_system(kernel_args* args)
{
	PartitionStack partitions;
	status_t status = get_boot_partitions(args, partitions);
	if (status < B_OK) {
		panic("get_boot_partitions failed!");
	}
	if (partitions.IsEmpty()) {
		panic("did not find any boot partitions!");
	}

	KPartition* bootPartition;
	while (partitions.Pop(&bootPartition)) {
		KPath path;
		if (bootPartition->GetPath(&path) != B_OK)
			panic("could not get boot device!\n");

		const char* fsName = NULL;
		bool readOnly = false;
		if (strcmp(bootPartition->ContentType(), "ISO9660 File System") == 0) {
			fsName = "iso9660:write_overlay:attribute_overlay";
			readOnly = true;
		} else if (bootPartition->IsReadOnly()
			&& strcmp(bootPartition->ContentType(), "Be File System") == 0) {
			fsName = "bfs:write_overlay";
			readOnly = true;
		}

		TRACE(("trying to mount boot partition: %s\n", path.Path()));
		gBootDevice = _kern_mount("/boot", path.Path(), fsName, 0, NULL, 0);
		if (gBootDevice >= B_OK) {
			gReadOnlyBootDevice = readOnly;
			break;
		}
	}

	if (gBootDevice < B_OK)
		panic("could not mount boot device!\n");

	// create link for the name of the boot device

	fs_info info;
	if (_kern_read_fs_info(gBootDevice, &info) == B_OK) {
		char path[B_FILE_NAME_LENGTH + 1];
		snprintf(path, sizeof(path), "/%s", info.volume_name);

		_kern_create_symlink(-1, path, "/boot", 0);
	}

	// Do post-boot-volume module initialization. The module code wants to know
	// whether the module images the boot loader has pre-loaded are the same as
	// on the boot volume. That is the case when booting from hard disk or CD,
	// but not via network.
	int32 bootMethodType = args->boot_volume.GetInt32(BOOT_METHOD,
		BOOT_METHOD_DEFAULT);
	bool bootingFromBootLoaderVolume = bootMethodType == BOOT_METHOD_HARD_DISK
		|| bootMethodType == BOOT_METHOD_CD;
	module_init_post_boot_device(bootingFromBootLoaderVolume);

	file_cache_init_post_boot_device();

	// search for other disk systems
	KDiskDeviceManager *manager = KDiskDeviceManager::Default();
	manager->RescanDiskSystems();
	manager->StartMonitoring();
}

status_t
_user_set_partition_parameters(partition_id partitionID, int32* _changeCounter,
	partition_id childID, int32* _childChangeCounter, const char* _parameters)
{
	// copy parameters in
	UserStringParameter<true> parameters;
	int32 changeCounter;
	int32 childChangeCounter;

	status_t error
		= parameters.Init(_parameters, B_DISK_DEVICE_MAX_PARAMETER_SIZE);
	if (error == B_OK)
		error = copy_from_user_value(changeCounter, _changeCounter);
	if (error == B_OK)
		error = copy_from_user_value(childChangeCounter, _childChangeCounter);
	if (error != B_OK)
		return error;

	// get the partition
	KDiskDeviceManager* manager = KDiskDeviceManager::Default();
	KPartition* partition = manager->WriteLockPartition(partitionID);
	if (partition == NULL)
		return B_ENTRY_NOT_FOUND;

	PartitionRegistrar registrar1(partition, true);
	PartitionRegistrar registrar2(partition->Device(), true);
	DeviceWriteLocker locker(partition->Device(), true);

	// register child
	KPartition* child = manager->RegisterPartition(childID);
	if (child == NULL)
		return B_ENTRY_NOT_FOUND;

	PartitionRegistrar registrar3(child, true);

	// check change counters
	if (changeCounter != partition->ChangeCounter()
		|| childChangeCounter != child->ChangeCounter()) {
		return B_BAD_VALUE;
	}

	// the partition must be initialized
	KDiskSystem* diskSystem = partition->DiskSystem();
	if (diskSystem == NULL)
		return B_BAD_VALUE;

	// child must indeed be a child of partition
	if (child->Parent() != partition)
		return B_BAD_VALUE;

	// mark the partition busy and unlock
	if (partition->IsBusy() || child->IsBusy())
		return B_BUSY;
	partition->SetBusy(true);
	child->SetBusy(true);
	locker.Unlock();

	// set the child parameters
	error = diskSystem->SetParameters(child, parameters.value, DUMMY_JOB_ID);

	// re-lock and unmark busy
	locker.Lock();
	partition->SetBusy(false);
	child->SetBusy(false);

	if (error != B_OK)
		return error;

	// return change counters
	error = copy_to_user_value(_changeCounter, partition->ChangeCounter());
	if (error == B_OK)
		error = copy_to_user_value(_childChangeCounter, child->ChangeCounter());
	return error;
}

status_t
_user_resize_partition(partition_id partitionID, int32* _changeCounter,
	partition_id childID, int32* _childChangeCounter, off_t size,
	off_t contentSize)
{
	// copy parameters in
	int32 changeCounter;
	int32 childChangeCounter;

	status_t error = copy_from_user_value(changeCounter, _changeCounter);
	if (error == B_OK)
		error = copy_from_user_value(childChangeCounter, _childChangeCounter);
	if (error != B_OK)
		return error;

	// get the partition
	KDiskDeviceManager* manager = KDiskDeviceManager::Default();
	KPartition* partition = manager->WriteLockPartition(partitionID);
	if (partition == NULL)
		return B_ENTRY_NOT_FOUND;

	PartitionRegistrar registrar1(partition, true);
	PartitionRegistrar registrar2(partition->Device(), true);
	DeviceWriteLocker locker(partition->Device(), true);

	// register child
	KPartition* child = manager->RegisterPartition(childID);
	if (child == NULL)
		return B_ENTRY_NOT_FOUND;

	PartitionRegistrar registrar3(child, true);

	// check change counters
	if (changeCounter != partition->ChangeCounter()
		|| childChangeCounter != child->ChangeCounter()) {
		return B_BAD_VALUE;
	}

	// the partition must be initialized
	KDiskSystem* diskSystem = partition->DiskSystem();
	if (diskSystem == NULL)
		return B_BAD_VALUE;

	// child must indeed be a child of partition
	if (child->Parent() != partition)
		return B_BAD_VALUE;

	// check sizes
	if (size < 0 || contentSize < 0 || size < contentSize
		|| size > partition->ContentSize()) {
		return B_BAD_VALUE;
	}

	// mark the partitions busy and unlock
	if (partition->IsBusy() || child->IsBusy())
		return B_BUSY;
	partition->SetBusy(true);
	child->SetBusy(true);
	locker.Unlock();

	// resize contents first, if shrinking
	if (child->DiskSystem() && contentSize < child->ContentSize())
		error = child->DiskSystem()->Resize(child, contentSize, DUMMY_JOB_ID);

	// resize the partition
	if (error == B_OK && size != child->Size())
		error = diskSystem->ResizeChild(child, size, DUMMY_JOB_ID);

	// resize contents last, if growing
	if (error == B_OK && child->DiskSystem()
		&& contentSize > child->ContentSize()) {
		error = child->DiskSystem()->Resize(child, contentSize, DUMMY_JOB_ID);
	}

	// re-lock and unmark busy
	locker.Lock();
	partition->SetBusy(false);
	child->SetBusy(false);

	if (error != B_OK)
		return error;

	// return change counters
	error = copy_to_user_value(_changeCounter, partition->ChangeCounter());
	if (error == B_OK)
		error = copy_to_user_value(_childChangeCounter, child->ChangeCounter());
	return error;
}

status_t
_user_delete_child_partition(partition_id partitionID, int32* _changeCounter,
	partition_id childID, int32 childChangeCounter)
{
	// copy parameters in
	int32 changeCounter;

	status_t error;
	if ((error = copy_from_user_value(changeCounter, _changeCounter)) != B_OK)
		return error;

	// get the partition
	KDiskDeviceManager* manager = KDiskDeviceManager::Default();
	KPartition* partition = manager->WriteLockPartition(partitionID);
	if (partition == NULL)
		return B_ENTRY_NOT_FOUND;

	PartitionRegistrar registrar1(partition, true);
	PartitionRegistrar registrar2(partition->Device(), true);
	DeviceWriteLocker locker(partition->Device(), true);

	// register child
	KPartition* child = manager->RegisterPartition(childID);
	if (child == NULL)
		return B_ENTRY_NOT_FOUND;

	PartitionRegistrar registrar3(child, true);

	// check change counters
	if (changeCounter != partition->ChangeCounter()
		|| childChangeCounter != child->ChangeCounter()) {
		return B_BAD_VALUE;
	}

	// the partition must be initialized
	KDiskSystem* diskSystem = partition->DiskSystem();
	if (diskSystem == NULL)
		return B_BAD_VALUE;

	// child must indeed be a child of partition
	if (child->Parent() != partition)
		return B_BAD_VALUE;

	// mark the partition and child busy and unlock
	if (partition->IsBusy() || !child->CheckAndMarkBusy(true))
		return B_BUSY;
	partition->SetBusy(true);
	locker.Unlock();

	// delete the child
	error = diskSystem->DeleteChild(child, DUMMY_JOB_ID);

	// re-lock and unmark busy
	locker.Lock();
	partition->SetBusy(false);
	child->UnmarkBusy(true);

	if (error != B_OK)
		return error;

	// return change counter
	return copy_to_user_value(_changeCounter, partition->ChangeCounter());
}

status_t
_user_create_child_partition(partition_id partitionID, int32* _changeCounter,
	off_t offset, off_t size, const char* _type, const char* _name,
	const char* _parameters, partition_id* childID, int32* childChangeCounter)
{
	// copy parameters in
	UserStringParameter<false> type;
	UserStringParameter<true> name;
	UserStringParameter<true> parameters;
	int32 changeCounter;

	status_t error = type.Init(_type, B_DISK_DEVICE_TYPE_LENGTH);
	if (error == B_OK)
		error = name.Init(_name, B_DISK_DEVICE_NAME_LENGTH);
	if (error == B_OK)
		error = parameters.Init(_parameters, B_DISK_DEVICE_MAX_PARAMETER_SIZE);
	if (error == B_OK)
		error = copy_from_user_value(changeCounter, _changeCounter);
	if (error != B_OK)
		return error;

	// get the partition
	KDiskDeviceManager* manager = KDiskDeviceManager::Default();
	KPartition* partition = manager->WriteLockPartition(partitionID);
	if (partition == NULL)
		return B_ENTRY_NOT_FOUND;

	PartitionRegistrar registrar1(partition, true);
	PartitionRegistrar registrar2(partition->Device(), true);
	DeviceWriteLocker locker(partition->Device(), true);

	// check change counter
	if (changeCounter != partition->ChangeCounter())
		return B_BAD_VALUE;

	// the partition must be initialized
	KDiskSystem* diskSystem = partition->DiskSystem();
	if (diskSystem == NULL)
		return B_BAD_VALUE;

	// mark the partition busy and unlock
	if (!partition->CheckAndMarkBusy(false))
		return B_BUSY;
	locker.Unlock();

	// create the child
	KPartition *child = NULL;
	error = diskSystem->CreateChild(partition, offset, size, type.value,
		name.value, parameters.value, DUMMY_JOB_ID, &child, -1);

	// re-lock and unmark busy
	locker.Lock();
	partition->UnmarkBusy(false);

	if (error != B_OK)
		return error;

	if (child == NULL)
		return B_ERROR;

	child->UnmarkBusy(true);

	// return change counter and child ID
	error = copy_to_user_value(_changeCounter, partition->ChangeCounter());
	if (error == B_OK)
		error = copy_to_user_value(childID, child->ID());
	return error;
}

status_t
_user_uninitialize_partition(partition_id partitionID, int32* _changeCounter,
	partition_id parentID, int32* _parentChangeCounter)
{
	// copy parameters in
	int32 changeCounter;
	int32 parentChangeCounter;
	bool haveParent = parentID >= 0;

	status_t error = copy_from_user_value(changeCounter, _changeCounter);
	if (haveParent && error == B_OK)
		error = copy_from_user_value(parentChangeCounter, _parentChangeCounter);
	if (error != B_OK)
		return error;

	// get the partition
	KDiskDeviceManager* manager = KDiskDeviceManager::Default();
	KPartition* partition = manager->WriteLockPartition(partitionID);
	if (partition == NULL)
		return B_ENTRY_NOT_FOUND;

	PartitionRegistrar registrar1(partition, true);
	PartitionRegistrar registrar2(partition->Device(), true);
	DeviceWriteLocker locker(partition->Device(), true);

	// register parent
	KPartition* parent = NULL;
	if (haveParent)
		parent = manager->RegisterPartition(parentID);

	PartitionRegistrar registrar3(parent, true);

	// check change counter
	if (changeCounter != partition->ChangeCounter())
		return B_BAD_VALUE;
	if (haveParent && parentChangeCounter != parent->ChangeCounter())
		return B_BAD_VALUE;

	// the partition must be initialized
	if (partition->DiskSystem() == NULL)
		return B_BAD_VALUE;

	// check busy
	if (!partition->CheckAndMarkBusy(true))
		return B_BUSY;

	if (partition->IsMounted() || partition->IsChildMounted())
		return B_BAD_VALUE;

	KDiskSystem* diskSystem = partition->DiskSystem();

	locker.Unlock();

	// Let the disk system uninitialize the partition. This operation is not
	// mandatory. If implemented, it will destroy the on-disk structures, so
	// that the disk system cannot accidentally identify the partition later on.
	if (diskSystem != NULL)
		diskSystem->Uninitialize(partition, DUMMY_JOB_ID);

	// re-lock and uninitialize the partition object
	locker.Lock();
	error = partition->UninitializeContents(true);

	partition->UnmarkBusy(true);

	if (error != B_OK)
		return error;

	// return change counter
	error = copy_to_user_value(_changeCounter, partition->ChangeCounter());
	if (haveParent && error == B_OK)
		error = copy_to_user_value(_parentChangeCounter, parent->ChangeCounter());
	return error;
}

status_t
_user_initialize_partition(partition_id partitionID, int32* _changeCounter,
	const char* _diskSystemName, const char* _name, const char* _parameters)
{
	// copy parameters in
	UserStringParameter<false> diskSystemName;
	UserStringParameter<true> name;
	UserStringParameter<true> parameters;
	int32 changeCounter;

	status_t error
		= diskSystemName.Init(_diskSystemName, B_DISK_SYSTEM_NAME_LENGTH);
	if (error == B_OK)
		error = name.Init(_name, B_DISK_DEVICE_NAME_LENGTH);
	if (error == B_OK)
		error = parameters.Init(_parameters, B_DISK_DEVICE_MAX_PARAMETER_SIZE);
	if (error == B_OK)
		error = copy_from_user_value(changeCounter, _changeCounter);
	if (error != B_OK)
		return error;

	// get the partition
	KDiskDeviceManager* manager = KDiskDeviceManager::Default();
	KPartition* partition = manager->WriteLockPartition(partitionID);
	if (partition == NULL)
		return B_ENTRY_NOT_FOUND;

	PartitionRegistrar registrar1(partition, true);
	PartitionRegistrar registrar2(partition->Device(), true);
	DeviceWriteLocker locker(partition->Device(), true);

	// check change counter
	if (changeCounter != partition->ChangeCounter())
		return B_BAD_VALUE;

	// the partition must be uninitialized
	if (partition->DiskSystem() != NULL)
		return B_BAD_VALUE;

	// load the new disk system
	KDiskSystem *diskSystem = manager->LoadDiskSystem(diskSystemName.value,
		true);
	if (diskSystem == NULL)
		return B_ENTRY_NOT_FOUND;
	DiskSystemLoader loader(diskSystem, true);

	// mark the partition busy and unlock
	if (!partition->CheckAndMarkBusy(true))
		return B_BUSY;
	locker.Unlock();

	// let the disk system initialize the partition
	error = diskSystem->Initialize(partition, name.value, parameters.value,
		DUMMY_JOB_ID);

	// re-lock and unmark busy
	locker.Lock();
	partition->UnmarkBusy(true);

	if (error != B_OK)
		return error;

	// Set the disk system. Re-check whether a disk system is already set on the
	// partition. Some disk systems just write the on-disk structures and let
	// the DDM rescan the partition, in which case the disk system will already
	// be set. In very unfortunate cases the on-disk structure of the previous
	// disk system has not been destroyed and the previous disk system has a
	// higher priority than the new one. The old disk system will thus prevail.
	// Not setting the new disk system will at least prevent that the partition
	// object gets into an inconsistent state.
	if (partition->DiskSystem() == NULL)
		partition->SetDiskSystem(diskSystem);

	// return change counter
	return copy_to_user_value(_changeCounter, partition->ChangeCounter());
}