diff options
| -rw-r--r-- | src/com/android/launcher3/LauncherBackupHelper.java | 52 |
1 files changed, 33 insertions, 19 deletions
diff --git a/src/com/android/launcher3/LauncherBackupHelper.java b/src/com/android/launcher3/LauncherBackupHelper.java index 677855d0f..ade5a2bf9 100644 --- a/src/com/android/launcher3/LauncherBackupHelper.java +++ b/src/com/android/launcher3/LauncherBackupHelper.java @@ -928,7 +928,7 @@ public class LauncherBackupHelper implements BackupHelper { * in that case, do a full backup. * * @param oldState the read-0only file descriptor pointing to the old journal - * @return a Journal protocol bugffer + * @return a Journal protocol buffer */ private Journal readJournal(ParcelFileDescriptor oldState) { Journal journal = new Journal(); @@ -937,39 +937,51 @@ public class LauncherBackupHelper implements BackupHelper { } FileInputStream inStream = new FileInputStream(oldState.getFileDescriptor()); try { - int remaining = inStream.available(); - if (DEBUG) Log.d(TAG, "available " + remaining); - if (remaining < MAX_JOURNAL_SIZE) { - byte[] buffer = new byte[remaining]; + int availableBytes = inStream.available(); + if (DEBUG) Log.d(TAG, "available " + availableBytes); + if (availableBytes < MAX_JOURNAL_SIZE) { + byte[] buffer = new byte[availableBytes]; int bytesRead = 0; - while (remaining > 0) { + boolean valid = false; + while (availableBytes > 0) { try { - int result = inStream.read(buffer, bytesRead, remaining); + // OMG what are you doing? This is crazy inefficient! + // If we read a byte that is not ours, we will cause trouble: b/12491813 + // However, we don't know how many bytes to expect (oops). + // So we have to step through *slowly*, watching for the end. + int result = inStream.read(buffer, bytesRead, 1); if (result > 0) { - if (DEBUG) Log.d(TAG, "read some bytes: " + result); - remaining -= result; + availableBytes -= result; bytesRead += result; + if (DEBUG && (bytesRead % 100 == 0)) { + Log.d(TAG, "read some bytes: " + bytesRead); + } } else { - // stop reading ands see what there is to parse - Log.w(TAG, "read error: " + result); - remaining = 0; + Log.w(TAG, "unexpected end of file while reading journal."); + // stop reading and see what there is to parse + availableBytes = 0; } } catch (IOException e) { - Log.w(TAG, "failed to read the journal", e); + Log.e(TAG, "failed to read the journal", e); buffer = null; - remaining = 0; + availableBytes = 0; } - } - if (DEBUG) Log.d(TAG, "journal bytes read: " + bytesRead); - if (buffer != null) { + // check the buffer to see if we have a valid journal try { MessageNano.mergeFrom(journal, readCheckedBytes(buffer, 0, bytesRead)); + // if we are here, then we have read a valid, checksum-verified journal + valid = true; + availableBytes = 0; } catch (InvalidProtocolBufferNanoException e) { - Log.d(TAG, "failed to read the journal", e); + // if we don't have the whole journal yet, mergeFrom will throw. keep going. journal.clear(); } } + if (DEBUG) Log.d(TAG, "journal bytes read: " + bytesRead); + if (!valid) { + Log.w(TAG, "failed to read the journal: could not find a valid journal"); + } } } catch (IOException e) { Log.d(TAG, "failed to close the journal", e); @@ -1038,7 +1050,9 @@ public class LauncherBackupHelper implements BackupHelper { FileOutputStream outStream = null; try { outStream = new FileOutputStream(newState.getFileDescriptor()); - outStream.write(writeCheckedBytes(journal)); + final byte[] journalBytes = writeCheckedBytes(journal); + if (DEBUG) Log.d(TAG, "writing " + journalBytes.length + " bytes of journal"); + outStream.write(journalBytes); outStream.close(); } catch (IOException e) { Log.d(TAG, "failed to write backup journal", e); |