C++ Partition::Parent方法代码示例

status_t
load_modules(stage2_args* args, BootVolume& volume)
{
	int32 failed = 0;

	// ToDo: this should be mostly replaced by a hardware oriented detection mechanism

	int32 i = 0;
	for (; sAddonPaths[i]; i++) {
		char path[B_FILE_NAME_LENGTH];
		snprintf(path, sizeof(path), "%s/boot", sAddonPaths[i]);

		if (load_modules_from(volume, path) != B_OK)
			failed++;
	}

	if (failed == i) {
		// couldn't load any boot modules
		// fall back to load all modules (currently needed by the boot floppy)
		const char *paths[] = { "bus_managers", "busses/ide", "busses/scsi",
			"generic", "partitioning_systems", "drivers/bin", NULL};

		for (int32 i = 0; paths[i]; i++) {
			char path[B_FILE_NAME_LENGTH];
			snprintf(path, sizeof(path), "%s/%s", sAddonPaths[0], paths[i]);
			load_modules_from(volume, path);
		}
	}

	// and now load all partitioning and file system modules
	// needed to identify the boot volume

	if (!gBootVolume.GetBool(BOOT_VOLUME_BOOTED_FROM_IMAGE, false)) {
		// iterate over the mounted volumes and load their file system
		Partition *partition;
		if (gRoot->GetPartitionFor(volume.RootDirectory(), &partition)
				== B_OK) {
			while (partition != NULL) {
				load_module(volume, partition->ModuleName());
				partition = partition->Parent();
			}
		}
	} else {
		// The boot image should only contain the file system
		// needed to boot the system, so we just load it.
		// ToDo: this is separate from the fall back from above
		//	as this piece will survive a more intelligent module
		//	loading approach...
		char path[B_FILE_NAME_LENGTH];
		snprintf(path, sizeof(path), "%s/%s", sAddonPaths[0], "file_systems");
		load_modules_from(volume, path);
	}

	return B_OK;
}

Partition::~Partition()
{
	TRACE(("%p Partition::~Partition\n", this));

	// Tell the children that their parent is gone

	NodeIterator iterator = gPartitions.GetIterator();
	Partition *child;

	while ((child = (Partition *)iterator.Next()) != NULL) {
		if (child->Parent() == this)
			child->SetParent(NULL);
	}

	close(fFD);
}

status_t
Partition::Scan(bool mountFileSystems, bool isBootDevice)
{
	// scan for partitions first (recursively all eventual children as well)

	TRACE(("%p Partition::Scan()\n", this));

	// if we were not booted from the real boot device, we won't scan
	// the device we were booted from (which is likely to be a slow
	// floppy or CD)
	if (isBootDevice && gKernelArgs.boot_volume.GetBool(
			BOOT_VOLUME_BOOTED_FROM_IMAGE, false)) {
		return B_ENTRY_NOT_FOUND;
	}

	const partition_module_info *bestModule = NULL;
	void *bestCookie = NULL;
	float bestPriority = -1;

	for (int32 i = 0; i < sNumPartitionModules; i++) {
		const partition_module_info *module = sPartitionModules[i];
		void *cookie = NULL;
		NodeOpener opener(this, O_RDONLY);

		TRACE(("check for partitioning_system: %s\n", module->pretty_name));

		float priority
			= module->identify_partition(opener.Descriptor(), this, &cookie);
		if (priority < 0.0)
			continue;

		TRACE(("  priority: %ld\n", (int32)(priority * 1000)));
		if (priority <= bestPriority) {
			// the disk system recognized the partition worse than the currently
			// best one
			module->free_identify_partition_cookie(this, cookie);
			continue;
		}

		// a new winner, replace the previous one
		if (bestModule)
			bestModule->free_identify_partition_cookie(this, bestCookie);
		bestModule = module;
		bestCookie = cookie;
		bestPriority = priority;
	}

	// find the best FS module
	const file_system_module_info *bestFSModule = NULL;
	float bestFSPriority = -1;
	for (int32 i = 0; i < sNumFileSystemModules; i++) {
		if (sFileSystemModules[i]->identify_file_system == NULL)
			continue;

		float priority = sFileSystemModules[i]->identify_file_system(this);
		if (priority <= 0)
			continue;

		if (priority > bestFSPriority) {
			bestFSModule = sFileSystemModules[i];
			bestFSPriority = priority;
		}
	}

	// now let the best matching disk system scan the partition
	if (bestModule && bestPriority >= bestFSPriority) {
		NodeOpener opener(this, O_RDONLY);
		status_t status = bestModule->scan_partition(opener.Descriptor(), this,
			bestCookie);
		bestModule->free_identify_partition_cookie(this, bestCookie);

		if (status != B_OK) {
			dprintf("Partitioning module `%s' recognized the partition, but "
				"failed to scan it\n", bestModule->pretty_name);
			return status;
		}

		fIsPartitioningSystem = true;

		content_type = bestModule->pretty_name;
		flags |= B_PARTITION_PARTITIONING_SYSTEM;

		// now that we've found something, check our children
		// out as well!

		NodeIterator iterator = fChildren.GetIterator();
		Partition *child = NULL;

		while ((child = (Partition *)iterator.Next()) != NULL) {
			TRACE(("%p Partition::Scan(): scan child %p (start = %Ld, size "
				"= %Ld, parent = %p)!\n", this, child, child->offset,
				child->size, child->Parent()));

			child->Scan(mountFileSystems);

			if (!mountFileSystems || child->IsFileSystem()) {
				// move the partitions containing file systems to the partition
				// list
				fChildren.Remove(child);
				gPartitions.Add(child);
//.........这里部分代码省略.........