Hook up the backup data writer, and add a utility to read the backup data files. (473b6e2d) · Commits · e / os / platform_frameworks_native

include/utils/backup_helpers.h

+16 −8

Original line number	Original line	Diff line number	Diff line
	@@ -22,24 +22,27 @@

	namespace android {		namespace android {

	int back_up_files(int oldSnapshotFD, int oldDataStream, int newSnapshotFD,		enum {
	char const* fileBase, char const* const* files, int fileCount);		BACKUP_HEADER_APP_V1 = 0x31707041, // App1 (little endian)
			BACKUP_HEADER_ENTITY_V1 = 0x61746144, // Data (little endian)
			BACKUP_FOOTER_APP_V1 = 0x746f6f46, // Foot (little endian)
			};

	// the sizes of all of these match.		// the sizes of all of these match.
	typedef struct {		typedef struct {
	int type; // == APP_MAGIC_V1		int type; // == BACKUP_HEADER_APP_V1
	int packageLen; // length of the name of the package that follows, not including the null.		int packageLen; // length of the name of the package that follows, not including the null.
	int cookie;		int cookie;
	} app_header_v1;		} app_header_v1;

	typedef struct {		typedef struct {
	int type; // ENTITY_MAGIC_V1		int type; // BACKUP_HEADER_ENTITY_V1
	int keyLen; // length of the key name, not including the null terminator		int keyLen; // length of the key name, not including the null terminator
	int dataSize; // size of the data, not including the padding		int dataSize; // size of the data, not including the padding, -1 means delete
	} entity_header_v1;		} entity_header_v1;

	typedef struct {		typedef struct {
	int type; // FOOTER_MAGIC_V1		int type; // BACKUP_FOOTER_APP_V1
	int entityCount; // the number of entities that were written		int entityCount; // the number of entities that were written
	int cookie;		int cookie;
	} app_footer_v1;		} app_footer_v1;
	@@ -89,11 +92,12 @@ public:
	~BackupDataReader();		~BackupDataReader();

	status_t Status();		status_t Status();
	status_t ReadNextHeader();		status_t ReadNextHeader(int* type = NULL);

	status_t ReadAppHeader(String8* packageName, int* cookie);		status_t ReadAppHeader(String8* packageName, int* cookie);
	bool HasEntities();		bool HasEntities();
	status_t ReadEntityHeader(String8* key, size_t* dataSize);		status_t ReadEntityHeader(String8* key, size_t* dataSize);
			status_t SkipEntityData(); // must be called with the pointer at the begining of the data.
	status_t ReadEntityData(void* data, size_t size);		status_t ReadEntityData(void* data, size_t size);
	status_t ReadAppFooter(int* cookie);		status_t ReadAppFooter(int* cookie);

	@@ -113,7 +117,11 @@ private:
	} m_header;		} m_header;
	};		};

	#define TEST_BACKUP_HELPERS 0		int back_up_files(int oldSnapshotFD, BackupDataWriter* dataStream, int newSnapshotFD,
			char const* fileBase, char const* const* files, int fileCount);


			#define TEST_BACKUP_HELPERS 1

	#if TEST_BACKUP_HELPERS		#if TEST_BACKUP_HELPERS
	int backup_helper_test_empty();		int backup_helper_test_empty();

libs/utils/backup_data.cpp

+32 −21

Original line number	Original line	Diff line number	Diff line
	@@ -39,10 +39,6 @@ namespace android {
	* - The value, padded to 4 byte boundary		* - The value, padded to 4 byte boundary
	*/		*/

	#define APP_MAGIC_V1 0x31707041 // App1 (little endian)
	#define ENTITY_MAGIC_V1 0x61746144 // Data (little endian)
	#define FOOTER_MAGIC_V1 0x746f6f46 // Foot (little endian)

	const static int ROUND_UP[4] = { 0, 3, 2, 1 };		const static int ROUND_UP[4] = { 0, 3, 2, 1 };

	static inline size_t		static inline size_t
	@@ -108,7 +104,7 @@ BackupDataWriter::WriteAppHeader(const String8& packageName, int cookie)

	nameLen = packageName.length();		nameLen = packageName.length();

	header.type = tolel(APP_MAGIC_V1);		header.type = tolel(BACKUP_HEADER_APP_V1);
	header.packageLen = tolel(nameLen);		header.packageLen = tolel(nameLen);
	header.cookie = cookie;		header.cookie = cookie;

	@@ -148,7 +144,7 @@ BackupDataWriter::WriteEntityHeader(const String8& key, size_t dataSize)

	keyLen = key.length();		keyLen = key.length();

	header.type = tolel(ENTITY_MAGIC_V1);		header.type = tolel(BACKUP_HEADER_ENTITY_V1);
	header.keyLen = tolel(keyLen);		header.keyLen = tolel(keyLen);
	header.dataSize = tolel(dataSize);		header.dataSize = tolel(dataSize);

	@@ -209,7 +205,7 @@ BackupDataWriter::WriteAppFooter(int cookie)
	app_footer_v1 footer;		app_footer_v1 footer;
	ssize_t nameLen;		ssize_t nameLen;

	footer.type = tolel(FOOTER_MAGIC_V1);		footer.type = tolel(BACKUP_FOOTER_APP_V1);
	footer.entityCount = tolel(m_entityCount);		footer.entityCount = tolel(m_entityCount);
	footer.cookie = cookie;		footer.cookie = cookie;

	@@ -264,7 +260,7 @@ BackupDataReader::Status()
	} while(0)		} while(0)

	status_t		status_t
	BackupDataReader::ReadNextHeader()		BackupDataReader::ReadNextHeader(int* type)
	{		{
	if (m_status != NO_ERROR) {		if (m_status != NO_ERROR) {
	return m_status;		return m_status;
	@@ -280,7 +276,7 @@ BackupDataReader::ReadNextHeader()
	m_header.type = fromlel(m_header.type);		m_header.type = fromlel(m_header.type);
	switch (m_header.type)		switch (m_header.type)
	{		{
	case APP_MAGIC_V1:		case BACKUP_HEADER_APP_V1:
	m_header.app.packageLen = fromlel(m_header.app.packageLen);		m_header.app.packageLen = fromlel(m_header.app.packageLen);
	if (m_header.app.packageLen < 0) {		if (m_header.app.packageLen < 0) {
	LOGD("App header at %d has packageLen<0: 0x%08x\n", (int)m_pos,		LOGD("App header at %d has packageLen<0: 0x%08x\n", (int)m_pos,
	@@ -289,7 +285,7 @@ BackupDataReader::ReadNextHeader()
	}		}
	m_header.app.cookie = m_header.app.cookie;		m_header.app.cookie = m_header.app.cookie;
	break;		break;
	case ENTITY_MAGIC_V1:		case BACKUP_HEADER_ENTITY_V1:
	m_header.entity.keyLen = fromlel(m_header.entity.keyLen);		m_header.entity.keyLen = fromlel(m_header.entity.keyLen);
	if (m_header.entity.keyLen <= 0) {		if (m_header.entity.keyLen <= 0) {
	LOGD("Entity header at %d has keyLen<=0: 0x%08x\n", (int)m_pos,		LOGD("Entity header at %d has keyLen<=0: 0x%08x\n", (int)m_pos,
	@@ -297,14 +293,9 @@ BackupDataReader::ReadNextHeader()
	m_status = EINVAL;		m_status = EINVAL;
	}		}
	m_header.entity.dataSize = fromlel(m_header.entity.dataSize);		m_header.entity.dataSize = fromlel(m_header.entity.dataSize);
	if (m_header.entity.dataSize < 0) {
	LOGD("Entity header at %d has dataSize<0: 0x%08x\n", (int)m_pos,
	(int)m_header.entity.dataSize);
	m_status = EINVAL;
	}
	m_entityCount++;		m_entityCount++;
	break;		break;
	case FOOTER_MAGIC_V1:		case BACKUP_FOOTER_APP_V1:
	m_header.footer.entityCount = fromlel(m_header.footer.entityCount);		m_header.footer.entityCount = fromlel(m_header.footer.entityCount);
	if (m_header.footer.entityCount < 0) {		if (m_header.footer.entityCount < 0) {
	LOGD("Entity header at %d has entityCount<0: 0x%08x\n", (int)m_pos,		LOGD("Entity header at %d has entityCount<0: 0x%08x\n", (int)m_pos,
	@@ -318,6 +309,9 @@ BackupDataReader::ReadNextHeader()
	m_status = EINVAL;		m_status = EINVAL;
	}		}
	m_pos += sizeof(m_header);		m_pos += sizeof(m_header);
			if (type) {
			*type = m_header.type;
			}

	return m_status;		return m_status;
	}		}
	@@ -328,7 +322,7 @@ BackupDataReader::ReadAppHeader(String8* packageName, int* cookie)
	if (m_status != NO_ERROR) {		if (m_status != NO_ERROR) {
	return m_status;		return m_status;
	}		}
	if (m_header.type != APP_MAGIC_V1) {		if (m_header.type != BACKUP_HEADER_APP_V1) {
	return EINVAL;		return EINVAL;
	}		}
	size_t size = m_header.app.packageLen;		size_t size = m_header.app.packageLen;
	@@ -349,7 +343,7 @@ BackupDataReader::ReadAppHeader(String8* packageName, int* cookie)
	bool		bool
	BackupDataReader::HasEntities()		BackupDataReader::HasEntities()
	{		{
	return m_status == NO_ERROR && m_header.type == ENTITY_MAGIC_V1;		return m_status == NO_ERROR && m_header.type == BACKUP_HEADER_ENTITY_V1;
	}		}

	status_t		status_t
	@@ -358,10 +352,10 @@ BackupDataReader::ReadEntityHeader(String8* key, size_t* dataSize)
	if (m_status != NO_ERROR) {		if (m_status != NO_ERROR) {
	return m_status;		return m_status;
	}		}
	if (m_header.type != ENTITY_MAGIC_V1) {		if (m_header.type != BACKUP_HEADER_ENTITY_V1) {
	return EINVAL;		return EINVAL;
	}		}
	size_t size = m_header.app.packageLen;		size_t size = m_header.entity.keyLen;
	char* buf = key->lockBuffer(size);		char* buf = key->lockBuffer(size);
	if (key == NULL) {		if (key == NULL) {
	key->unlockBuffer();		key->unlockBuffer();
	@@ -377,6 +371,23 @@ BackupDataReader::ReadEntityHeader(String8* key, size_t* dataSize)
	return NO_ERROR;		return NO_ERROR;
	}		}

			status_t
			BackupDataReader::SkipEntityData()
			{
			if (m_status != NO_ERROR) {
			return m_status;
			}
			if (m_header.type != BACKUP_HEADER_ENTITY_V1) {
			return EINVAL;
			}
			if (m_header.entity.dataSize > 0) {
			int pos = lseek(m_fd, m_header.entity.dataSize, SEEK_CUR);
			return pos == -1 ? (int)errno : (int)NO_ERROR;
			} else {
			return NO_ERROR;
			}
			}

	status_t		status_t
	BackupDataReader::ReadEntityData(void* data, size_t size)		BackupDataReader::ReadEntityData(void* data, size_t size)
	{		{
	@@ -395,7 +406,7 @@ BackupDataReader::ReadAppFooter(int* cookie)
	if (m_status != NO_ERROR) {		if (m_status != NO_ERROR) {
	return m_status;		return m_status;
	}		}
	if (m_header.type != FOOTER_MAGIC_V1) {		if (m_header.type != BACKUP_FOOTER_APP_V1) {
	return EINVAL;		return EINVAL;
	}		}
	if (m_header.footer.entityCount != m_entityCount) {		if (m_header.footer.entityCount != m_entityCount) {

libs/utils/backup_helper_file.cpp

+117 −35

Original line number	Original line	Diff line number	Diff line
	@@ -40,7 +40,7 @@ namespace android {
	#define MAGIC0 0x70616e53 // Snap		#define MAGIC0 0x70616e53 // Snap
	#define MAGIC1 0x656c6946 // File		#define MAGIC1 0x656c6946 // File

	#if TEST_BACKUP_HELPERS		#if 0 // TEST_BACKUP_HELPERS
	#define LOGP(x...) printf(x)		#define LOGP(x...) printf(x)
	#else		#else
	#define LOGP(x...) LOGD(x)		#define LOGP(x...) LOGD(x)
	@@ -181,45 +181,105 @@ write_snapshot_file(int fd, const KeyedVector<String8,FileState>& snapshot)
	}		}

	static int		static int
	write_delete_file(const String8& key)		write_delete_file(BackupDataWriter* dataStream, const String8& key)
	{		{
	LOGP("write_delete_file %s\n", key.string());		LOGP("write_delete_file %s\n", key.string());
	return 0;		return dataStream->WriteEntityHeader(key, -1);
	}		}

	static int		static int
	write_update_file(const String8& realFilename, const String8& key)		write_update_file(BackupDataWriter* dataStream, int fd, const String8& key,
			const String8& realFilename)
	{		{
	LOGP("write_update_file %s (%s)\n", realFilename.string(), key.string());		LOGP("write_update_file %s (%s)\n", realFilename.string(), key.string());
	return 0;
	}

	static int
	compute_crc32(const String8& filename)
	{
	const int bufsize = 4*1024;		const int bufsize = 4*1024;
			int err;
	int amt;		int amt;
			int fileSize;
			int bytesLeft;

			char* buf = (char*)malloc(bufsize);
			int crc = crc32(0L, Z_NULL, 0);


			bytesLeft = fileSize = lseek(fd, 0, SEEK_END);
			lseek(fd, 0, SEEK_SET);

			err = dataStream->WriteEntityHeader(key, bytesLeft);
			if (err != 0) {
			return err;
			}

			while ((amt = read(fd, buf, bufsize)) != 0 && bytesLeft > 0) {
			bytesLeft -= amt;
			if (bytesLeft < 0) {
			amt += bytesLeft; // Plus a negative is minus. Don't write more than we promised.
			}
			err = dataStream->WriteEntityData(buf, amt);
			if (err != 0) {
			return err;
			}
			}
			if (bytesLeft != 0) {
			if (bytesLeft > 0) {
			// Pad out the space we promised in the buffer. We can't corrupt the buffer,
			// even though the data we're sending is probably bad.
			memset(buf, 0, bufsize);
			while (bytesLeft > 0) {
			amt = bytesLeft < bufsize ? bytesLeft : bufsize;
			bytesLeft -= amt;
			err = dataStream->WriteEntityData(buf, amt);
			if (err != 0) {
			return err;
			}
			}
			}
			LOGE("write_update_file size mismatch for %s. expected=%d actual=%d."
			" You aren't doing proper locking!",
			realFilename.string(), fileSize, fileSize-bytesLeft);
			}

			free(buf);

			return NO_ERROR;
			}

	int fd = open(filename.string(), O_RDONLY);		static int
			write_update_file(BackupDataWriter* dataStream, const String8& key, const String8& realFilename)
			{
			int err;
			int fd = open(realFilename.string(), O_RDONLY);
	if (fd == -1) {		if (fd == -1) {
	return -1;		return errno;
	}		}
			err = write_update_file(dataStream, fd, key, realFilename);
			close(fd);
			return err;
			}

			static int
			compute_crc32(int fd)
			{
			const int bufsize = 4*1024;
			int amt;

	char* buf = (char*)malloc(bufsize);		char* buf = (char*)malloc(bufsize);
	int crc = crc32(0L, Z_NULL, 0);		int crc = crc32(0L, Z_NULL, 0);

			lseek(fd, 0, SEEK_SET);

	while ((amt = read(fd, buf, bufsize)) != 0) {		while ((amt = read(fd, buf, bufsize)) != 0) {
	crc = crc32(crc, (Bytef*)buf, amt);		crc = crc32(crc, (Bytef*)buf, amt);
	}		}

	close(fd);
	free(buf);		free(buf);

	return crc;		return crc;
	}		}

	int		int
	back_up_files(int oldSnapshotFD, int oldDataStream, int newSnapshotFD,		back_up_files(int oldSnapshotFD, BackupDataWriter* dataStream, int newSnapshotFD,
	char const* fileBase, char const* const* files, int fileCount)		char const* fileBase, char const* const* files, int fileCount)
	{		{
	int err;		int err;
	@@ -252,7 +312,8 @@ back_up_files(int oldSnapshotFD, int oldDataStream, int newSnapshotFD,
	s.modTime_nsec = 0; // workaround sim breakage		s.modTime_nsec = 0; // workaround sim breakage
	//s.modTime_nsec = st.st_mtime_nsec;		//s.modTime_nsec = st.st_mtime_nsec;
	s.size = st.st_size;		s.size = st.st_size;
	s.crc32 = compute_crc32(realFilename);
			// we compute the crc32 later down below, when we already have the file open.

	newSnapshot.add(name, s);		newSnapshot.add(name, s);
	}		}
	@@ -270,21 +331,30 @@ back_up_files(int oldSnapshotFD, int oldDataStream, int newSnapshotFD,
	String8 realFilename(base);		String8 realFilename(base);
	realFilename.appendPath(q);		realFilename.appendPath(q);
	LOGP("file added: %s\n", realFilename.string());		LOGP("file added: %s\n", realFilename.string());
	write_update_file(realFilename, q);		write_update_file(dataStream, q, realFilename);
	m++;		m++;
	}		}
	else if (cmp < 0) {		else if (cmp < 0) {
	// file removed		// file removed
	LOGP("file removed: %s\n", p.string());		LOGP("file removed: %s\n", p.string());
	write_delete_file(p);		dataStream->WriteEntityHeader(p, -1);
	n++;		n++;
	}		}
	else {		else {

	// both files exist, check them		// both files exist, check them
	String8 realFilename(base);		String8 realFilename(base);
	realFilename.appendPath(q);		realFilename.appendPath(q);
	const FileState& f = oldSnapshot.valueAt(n);		const FileState& f = oldSnapshot.valueAt(n);
	const FileState& g = newSnapshot.valueAt(m);		FileState& g = newSnapshot.editValueAt(m);

			int fd = open(realFilename.string(), O_RDONLY);
			if (fd != -1) {
			// We can't open the file. Don't report it as a delete either. Let the
			// server keep the old version. Maybe they'll be able to deal with it
			// on restore.
			} else {
			g.crc32 = compute_crc32(fd);

	LOGP("%s\n", q.string());		LOGP("%s\n", q.string());
	LOGP(" new: modTime=%d,%d size=%-3d crc32=0x%08x\n",		LOGP(" new: modTime=%d,%d size=%-3d crc32=0x%08x\n",
	@@ -293,7 +363,10 @@ back_up_files(int oldSnapshotFD, int oldDataStream, int newSnapshotFD,
	g.modTime_sec, g.modTime_nsec, g.size, g.crc32);		g.modTime_sec, g.modTime_nsec, g.size, g.crc32);
	if (f.modTime_sec != g.modTime_sec \|\| f.modTime_nsec != g.modTime_nsec		if (f.modTime_sec != g.modTime_sec \|\| f.modTime_nsec != g.modTime_nsec
	\|\| f.size != g.size \|\| f.crc32 != g.crc32) {		\|\| f.size != g.size \|\| f.crc32 != g.crc32) {
	write_update_file(realFilename, p);		write_update_file(dataStream, fd, p, realFilename);
			}

			close(fd);
	}		}
	n++;		n++;
	m++;		m++;
	@@ -302,7 +375,7 @@ back_up_files(int oldSnapshotFD, int oldDataStream, int newSnapshotFD,

	// these were deleted		// these were deleted
	while (n<N) {		while (n<N) {
	write_delete_file(oldSnapshot.keyAt(n));		dataStream->WriteEntityHeader(oldSnapshot.keyAt(n), -1);
	n++;		n++;
	}		}

	@@ -311,7 +384,7 @@ back_up_files(int oldSnapshotFD, int oldDataStream, int newSnapshotFD,
	const String8& q = newSnapshot.keyAt(m);		const String8& q = newSnapshot.keyAt(m);
	String8 realFilename(base);		String8 realFilename(base);
	realFilename.appendPath(q);		realFilename.appendPath(q);
	write_update_file(realFilename, q);		write_update_file(dataStream, q, realFilename);
	m++;		m++;
	}		}

	@@ -912,10 +985,14 @@ backup_helper_test_files()
	return errno;		return errno;
	}		}

	err = back_up_files(-1, dataStreamFD, newSnapshotFD, SCRATCH_DIR, files_before, 5);		{
			BackupDataWriter dataStream(dataStreamFD);

			err = back_up_files(-1, &dataStream, newSnapshotFD, SCRATCH_DIR, files_before, 5);
	if (err != 0) {		if (err != 0) {
	return err;		return err;
	}		}
			}

	close(dataStreamFD);		close(dataStreamFD);
	close(newSnapshotFD);		close(newSnapshotFD);
	@@ -968,10 +1045,15 @@ backup_helper_test_files()
	return errno;		return errno;
	}		}

	err = back_up_files(oldSnapshotFD, dataStreamFD, newSnapshotFD, SCRATCH_DIR, files_after, 6);		{
			BackupDataWriter dataStream(dataStreamFD);

			err = back_up_files(oldSnapshotFD, &dataStream, newSnapshotFD, SCRATCH_DIR,
			files_after, 6);
	if (err != 0) {		if (err != 0) {
	return err;		return err;
	}		}
			}

	close(oldSnapshotFD);		close(oldSnapshotFD);
	close(dataStreamFD);		close(dataStreamFD);