Hook up the backup data writer, and add a utility to read the backup data files.
diff --git a/include/utils/backup_helpers.h b/include/utils/backup_helpers.h
index 0c59fec..24b6c9e 100644
--- a/include/utils/backup_helpers.h
+++ b/include/utils/backup_helpers.h
@@ -22,24 +22,27 @@
namespace android {
-int back_up_files(int oldSnapshotFD, int oldDataStream, int newSnapshotFD,
- char const* fileBase, char const* const* files, int fileCount);
+enum {
+ 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.
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 cookie;
} app_header_v1;
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 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;
typedef struct {
- int type; // FOOTER_MAGIC_V1
+ int type; // BACKUP_FOOTER_APP_V1
int entityCount; // the number of entities that were written
int cookie;
} app_footer_v1;
@@ -89,11 +92,12 @@
~BackupDataReader();
status_t Status();
- status_t ReadNextHeader();
+ status_t ReadNextHeader(int* type = NULL);
status_t ReadAppHeader(String8* packageName, int* cookie);
bool HasEntities();
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 ReadAppFooter(int* cookie);
@@ -113,7 +117,11 @@
} 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
int backup_helper_test_empty();
diff --git a/libs/utils/backup_data.cpp b/libs/utils/backup_data.cpp
index dd04449..95c05b7 100644
--- a/libs/utils/backup_data.cpp
+++ b/libs/utils/backup_data.cpp
@@ -39,10 +39,6 @@
* - 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 };
static inline size_t
@@ -108,7 +104,7 @@
nameLen = packageName.length();
- header.type = tolel(APP_MAGIC_V1);
+ header.type = tolel(BACKUP_HEADER_APP_V1);
header.packageLen = tolel(nameLen);
header.cookie = cookie;
@@ -148,7 +144,7 @@
keyLen = key.length();
- header.type = tolel(ENTITY_MAGIC_V1);
+ header.type = tolel(BACKUP_HEADER_ENTITY_V1);
header.keyLen = tolel(keyLen);
header.dataSize = tolel(dataSize);
@@ -209,7 +205,7 @@
app_footer_v1 footer;
ssize_t nameLen;
- footer.type = tolel(FOOTER_MAGIC_V1);
+ footer.type = tolel(BACKUP_FOOTER_APP_V1);
footer.entityCount = tolel(m_entityCount);
footer.cookie = cookie;
@@ -264,7 +260,7 @@
} while(0)
status_t
-BackupDataReader::ReadNextHeader()
+BackupDataReader::ReadNextHeader(int* type)
{
if (m_status != NO_ERROR) {
return m_status;
@@ -280,7 +276,7 @@
m_header.type = fromlel(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);
if (m_header.app.packageLen < 0) {
LOGD("App header at %d has packageLen<0: 0x%08x\n", (int)m_pos,
@@ -289,7 +285,7 @@
}
m_header.app.cookie = m_header.app.cookie;
break;
- case ENTITY_MAGIC_V1:
+ case BACKUP_HEADER_ENTITY_V1:
m_header.entity.keyLen = fromlel(m_header.entity.keyLen);
if (m_header.entity.keyLen <= 0) {
LOGD("Entity header at %d has keyLen<=0: 0x%08x\n", (int)m_pos,
@@ -297,14 +293,9 @@
m_status = EINVAL;
}
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++;
break;
- case FOOTER_MAGIC_V1:
+ case BACKUP_FOOTER_APP_V1:
m_header.footer.entityCount = fromlel(m_header.footer.entityCount);
if (m_header.footer.entityCount < 0) {
LOGD("Entity header at %d has entityCount<0: 0x%08x\n", (int)m_pos,
@@ -318,6 +309,9 @@
m_status = EINVAL;
}
m_pos += sizeof(m_header);
+ if (type) {
+ *type = m_header.type;
+ }
return m_status;
}
@@ -328,7 +322,7 @@
if (m_status != NO_ERROR) {
return m_status;
}
- if (m_header.type != APP_MAGIC_V1) {
+ if (m_header.type != BACKUP_HEADER_APP_V1) {
return EINVAL;
}
size_t size = m_header.app.packageLen;
@@ -349,7 +343,7 @@
bool
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
@@ -358,10 +352,10 @@
if (m_status != NO_ERROR) {
return m_status;
}
- if (m_header.type != ENTITY_MAGIC_V1) {
+ if (m_header.type != BACKUP_HEADER_ENTITY_V1) {
return EINVAL;
}
- size_t size = m_header.app.packageLen;
+ size_t size = m_header.entity.keyLen;
char* buf = key->lockBuffer(size);
if (key == NULL) {
key->unlockBuffer();
@@ -378,6 +372,23 @@
}
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
BackupDataReader::ReadEntityData(void* data, size_t size)
{
if (m_status != NO_ERROR) {
@@ -395,7 +406,7 @@
if (m_status != NO_ERROR) {
return m_status;
}
- if (m_header.type != FOOTER_MAGIC_V1) {
+ if (m_header.type != BACKUP_FOOTER_APP_V1) {
return EINVAL;
}
if (m_header.footer.entityCount != m_entityCount) {
diff --git a/libs/utils/backup_helper_file.cpp b/libs/utils/backup_helper_file.cpp
index bf56945..8efb3eb 100644
--- a/libs/utils/backup_helper_file.cpp
+++ b/libs/utils/backup_helper_file.cpp
@@ -40,7 +40,7 @@
#define MAGIC0 0x70616e53 // Snap
#define MAGIC1 0x656c6946 // File
-#if TEST_BACKUP_HELPERS
+#if 0 // TEST_BACKUP_HELPERS
#define LOGP(x...) printf(x)
#else
#define LOGP(x...) LOGD(x)
@@ -181,45 +181,105 @@
}
static int
-write_delete_file(const String8& key)
+write_delete_file(BackupDataWriter* dataStream, const String8& key)
{
LOGP("write_delete_file %s\n", key.string());
- return 0;
+ return dataStream->WriteEntityHeader(key, -1);
}
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());
- return 0;
+
+ const int bufsize = 4*1024;
+ int err;
+ 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;
}
static int
-compute_crc32(const String8& filename)
+write_update_file(BackupDataWriter* dataStream, const String8& key, const String8& realFilename)
+{
+ int err;
+ int fd = open(realFilename.string(), O_RDONLY);
+ if (fd == -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;
- int fd = open(filename.string(), O_RDONLY);
- if (fd == -1) {
- return -1;
- }
-
char* buf = (char*)malloc(bufsize);
int crc = crc32(0L, Z_NULL, 0);
+ lseek(fd, 0, SEEK_SET);
+
while ((amt = read(fd, buf, bufsize)) != 0) {
crc = crc32(crc, (Bytef*)buf, amt);
}
- close(fd);
free(buf);
return crc;
}
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)
{
int err;
@@ -252,7 +312,8 @@
s.modTime_nsec = 0; // workaround sim breakage
//s.modTime_nsec = st.st_mtime_nsec;
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);
}
@@ -270,30 +331,42 @@
String8 realFilename(base);
realFilename.appendPath(q);
LOGP("file added: %s\n", realFilename.string());
- write_update_file(realFilename, q);
+ write_update_file(dataStream, q, realFilename);
m++;
}
else if (cmp < 0) {
// file removed
LOGP("file removed: %s\n", p.string());
- write_delete_file(p);
+ dataStream->WriteEntityHeader(p, -1);
n++;
}
else {
+
// both files exist, check them
String8 realFilename(base);
realFilename.appendPath(q);
const FileState& f = oldSnapshot.valueAt(n);
- const FileState& g = newSnapshot.valueAt(m);
+ FileState& g = newSnapshot.editValueAt(m);
- LOGP("%s\n", q.string());
- LOGP(" new: modTime=%d,%d size=%-3d crc32=0x%08x\n",
- f.modTime_sec, f.modTime_nsec, f.size, f.crc32);
- LOGP(" old: modTime=%d,%d size=%-3d crc32=0x%08x\n",
- g.modTime_sec, g.modTime_nsec, g.size, g.crc32);
- if (f.modTime_sec != g.modTime_sec || f.modTime_nsec != g.modTime_nsec
- || f.size != g.size || f.crc32 != g.crc32) {
- write_update_file(realFilename, p);
+ 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(" new: modTime=%d,%d size=%-3d crc32=0x%08x\n",
+ f.modTime_sec, f.modTime_nsec, f.size, f.crc32);
+ LOGP(" old: modTime=%d,%d size=%-3d crc32=0x%08x\n",
+ g.modTime_sec, g.modTime_nsec, g.size, g.crc32);
+ if (f.modTime_sec != g.modTime_sec || f.modTime_nsec != g.modTime_nsec
+ || f.size != g.size || f.crc32 != g.crc32) {
+ write_update_file(dataStream, fd, p, realFilename);
+ }
+
+ close(fd);
}
n++;
m++;
@@ -302,7 +375,7 @@
// these were deleted
while (n<N) {
- write_delete_file(oldSnapshot.keyAt(n));
+ dataStream->WriteEntityHeader(oldSnapshot.keyAt(n), -1);
n++;
}
@@ -311,7 +384,7 @@
const String8& q = newSnapshot.keyAt(m);
String8 realFilename(base);
realFilename.appendPath(q);
- write_update_file(realFilename, q);
+ write_update_file(dataStream, q, realFilename);
m++;
}
@@ -911,10 +984,14 @@
fprintf(stderr, "error creating: %s\n", strerror(errno));
return errno;
}
+
+ {
+ BackupDataWriter dataStream(dataStreamFD);
- err = back_up_files(-1, dataStreamFD, newSnapshotFD, SCRATCH_DIR, files_before, 5);
- if (err != 0) {
- return err;
+ err = back_up_files(-1, &dataStream, newSnapshotFD, SCRATCH_DIR, files_before, 5);
+ if (err != 0) {
+ return err;
+ }
}
close(dataStreamFD);
@@ -968,10 +1045,15 @@
return errno;
}
- err = back_up_files(oldSnapshotFD, dataStreamFD, newSnapshotFD, SCRATCH_DIR, files_after, 6);
- if (err != 0) {
- return err;
- }
+ {
+ BackupDataWriter dataStream(dataStreamFD);
+
+ err = back_up_files(oldSnapshotFD, &dataStream, newSnapshotFD, SCRATCH_DIR,
+ files_after, 6);
+ if (err != 0) {
+ return err;
+ }
+}
close(oldSnapshotFD);
close(dataStreamFD);