Hook up the backup data writer, and add a utility to read the backup data files.

14 files changed, 605 insertions, 93 deletions

diff --git a/cmds/backup/Android.mk b/cmds/backup/Android.mk
new file mode 100644
index 0000000..a37a80e
--- /dev/null
+++ b/cmds/backup/Android.mk
@@ -0,0 +1,15 @@
+# Copyright 2009 The Android Open Source Project
+
+LOCAL_PATH:= $(call my-dir)
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES:= backup.cpp
+
+LOCAL_SHARED_LIBRARIES := libcutils libc libutils
+
+LOCAL_MODULE:= btool
+
+LOCAL_MODULE_PATH := $(TARGET_OUT_OPTIONAL_EXECUTABLES)
+LOCAL_MODULE_TAGS := debug
+
+include $(BUILD_EXECUTABLE)
diff --git a/cmds/backup/NOTICE b/cmds/backup/NOTICE
new file mode 100644
index 0000000..c5b1efa
--- /dev/null
+++ b/cmds/backup/NOTICE
@@ -0,0 +1,190 @@
+
+   Copyright (c) 2005-2008, The Android Open Source Project
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
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+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
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+      including but not limited to software source code, documentation
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+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
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+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
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+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
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+      Work and such Derivative Works in Source or Object form.
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+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
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+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
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+          include a readable copy of the attribution notices contained
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+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
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+          notices within Derivative Works that You distribute, alongside
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+          that such additional attribution notices cannot be construed
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+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
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+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
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+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
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+      other commercial damages or losses), even if such Contributor
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+   9. Accepting Warranty or Additional Liability. While redistributing
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+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
diff --git a/cmds/backup/backup.cpp b/cmds/backup/backup.cpp
new file mode 100644
index 0000000..51ac943
--- /dev/null
+++ b/cmds/backup/backup.cpp
@@ -0,0 +1,122 @@
+
+#include <utils/backup_helpers.h>
+#include <utils/String8.h>
+
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+
+using namespace android;
+
+#include <unistd.h>
+
+int
+usage(int argc, const char** argv)
+{
+    const char* p = argv[0];
+
+    fprintf(stderr, "%s: Backs up your data.\n"
+                    "\n"
+                    "usage: %s\n"
+                    "  Prints all of the data that can be backed up to stdout.\n"
+                    "\n"
+                    "usage: %s list FILE\n"
+                    "  Lists the backup entities in the file.\n"
+                    "\n"
+                    "usage: %s print NAME FILE\n"
+                    "  Prints the entity named NAME in FILE.\n",
+                    p, p, p, p);
+    return 1;
+}
+
+int
+perform_full_backup()
+{
+    printf("this would have written all of your data to stdout\n");
+    return 0;
+}
+
+int
+perform_list(const char* filename)
+{
+    int err;
+    int fd;
+
+    fd = open(filename, O_RDONLY);
+    if (fd == -1) {
+        fprintf(stderr, "Error opening: %s\n", filename);
+        return 1;
+    }
+
+    BackupDataReader reader(fd);
+    int type;
+
+    while (reader.ReadNextHeader(&type) == 0) {
+        switch (type) {
+            case BACKUP_HEADER_APP_V1:
+            {
+                String8 packageName;
+                int cookie;
+                err = reader.ReadAppHeader(&packageName, &cookie);
+                if (err == 0) {
+                    printf("App header: %s 0x%08x (%d)\n", packageName.string(), cookie, cookie);
+                } else {
+                    printf("Error reading app header\n");
+                }
+                break;
+            }
+            case BACKUP_HEADER_ENTITY_V1:
+            {
+                String8 key;
+                size_t dataSize;
+                err = reader.ReadEntityHeader(&key, &dataSize);
+                if (err == 0) {
+                    printf("   entity: %s (%d bytes)\n", key.string(), dataSize);
+                } else {
+                    printf("   Error reading entity header\n");
+                }
+                break;
+            }
+            case BACKUP_FOOTER_APP_V1:
+            {
+                int cookie;
+                err = reader.ReadAppFooter(&cookie);
+                if (err == 0) {
+                    printf("   App footer: 0x%08x (%d)\n", cookie, cookie);
+                } else {
+                    printf("   Error reading entity header\n");
+                }
+                break;
+            }
+            default:
+            {
+                printf("Unknown chunk type: 0x%08x\n", type);
+                break;
+            }
+        }
+    }
+
+    return 0;
+}
+
+int perform_print(const char* entityname, const char* filename)
+{
+    printf("perform_print(%s, %s);", entityname, filename);
+    return 0;
+}
+
+int
+main(int argc, const char** argv)
+{
+    if (argc <= 1) {
+        return perform_full_backup();
+    }
+    if (argc == 3 && 0 == strcmp(argv[1], "list")) {
+        return perform_list(argv[2]);
+    }
+    if (argc == 4 && 0 == strcmp(argv[1], "print")) {
+        return perform_print(argv[2], argv[3]);
+    }
+    return usage(argc, argv);
+}
+
diff --git a/core/java/android/backup/BackupDataOutput.java b/core/java/android/backup/BackupDataOutput.java
index 555494e..25ae15b 100644
--- a/core/java/android/backup/BackupDataOutput.java
+++ b/core/java/android/backup/BackupDataOutput.java
@@ -22,24 +22,30 @@ import java.io.FileDescriptor;
 
 /** @hide */
 public class BackupDataOutput {
-    /* package */ FileDescriptor fd;
+    int mBackupWriter;
+    private Context mContext;
 
     public static final int OP_UPDATE = 1;
     public static final int OP_DELETE = 2;
 
     public BackupDataOutput(Context context, FileDescriptor fd) {
-        this.fd = fd;
+        mContext = context;
+        if (fd == null) throw new NullPointerException();
+        mBackupWriter = ctor(fd);
+        if (mBackupWriter == 0) {
+            throw new RuntimeException("Native initialization failed with fd=" + fd);
+        }
     }
 
-    public void close() {
-        // do we close the fd?
+    protected void finalize() throws Throwable {
+        try {
+            dtor(mBackupWriter);
+        } finally {
+            super.finalize();
+        }
     }
-    public native void flush();
-    public native void write(byte[] buffer);
-    public native void write(int oneByte);
-    public native void write(byte[] buffer, int offset, int count);
-
-    public native void writeOperation(int op);
-    public native void writeKey(String key);
+        
+    private native static int ctor(FileDescriptor fd);
+    private native static void dtor(int mBackupWriter);
 }
 
diff --git a/core/java/android/backup/FileBackupHelper.java b/core/java/android/backup/FileBackupHelper.java
index 05159dc..ec16eb1 100644
--- a/core/java/android/backup/FileBackupHelper.java
+++ b/core/java/android/backup/FileBackupHelper.java
@@ -53,15 +53,12 @@ public class FileBackupHelper {
         }
         // oldStateFd can be null
         FileDescriptor oldStateFd = oldState != null ? oldState.getFileDescriptor() : null;
-        if (data.fd == null) {
-            throw new NullPointerException();
-        }
         FileDescriptor newStateFd = newState.getFileDescriptor();
         if (newStateFd == null) {
             throw new NullPointerException();
         }
 
-        int err = performBackup_native(basePath, oldStateFd, data.fd, newStateFd, files);
+        int err = performBackup_native(basePath, oldStateFd, data.mBackupWriter, newStateFd, files);
 
         if (err != 0) {
             throw new RuntimeException("Backup failed"); // TODO: more here
@@ -69,5 +66,5 @@ public class FileBackupHelper {
     }
 
     native private static int performBackup_native(String basePath, FileDescriptor oldState,
-            FileDescriptor data, FileDescriptor newState, String[] files);
+            int data, FileDescriptor newState, String[] files);
 }
diff --git a/core/jni/Android.mk b/core/jni/Android.mk
index 4839b6f..d46dd80 100644
--- a/core/jni/Android.mk
+++ b/core/jni/Android.mk
@@ -117,6 +117,7 @@ LOCAL_SRC_FILES:= \
 	android_location_GpsLocationProvider.cpp \
 	com_android_internal_os_ZygoteInit.cpp \
 	com_android_internal_graphics_NativeUtils.cpp \
+	android_backup_BackupDataOutput.cpp \
 	android_backup_FileBackupHelper.cpp
 
 LOCAL_C_INCLUDES += \
diff --git a/core/jni/AndroidRuntime.cpp b/core/jni/AndroidRuntime.cpp
index aa6450d..302f39e 100644
--- a/core/jni/AndroidRuntime.cpp
+++ b/core/jni/AndroidRuntime.cpp
@@ -155,6 +155,7 @@ extern int register_android_ddm_DdmHandleNativeHeap(JNIEnv *env);
 extern int register_com_android_internal_os_ZygoteInit(JNIEnv* env);
 extern int register_android_util_Base64(JNIEnv* env);
 extern int register_android_location_GpsLocationProvider(JNIEnv* env);
+extern int register_android_backup_BackupDataOutput(JNIEnv *env);
 extern int register_android_backup_FileBackupHelper(JNIEnv *env);
 
 static AndroidRuntime* gCurRuntime = NULL;
@@ -1126,6 +1127,7 @@ static const RegJNIRec gRegJNI[] = {
     REG_JNI(register_android_ddm_DdmHandleNativeHeap),
     REG_JNI(register_android_util_Base64),
     REG_JNI(register_android_location_GpsLocationProvider),
+    REG_JNI(register_android_backup_BackupDataOutput),
     REG_JNI(register_android_backup_FileBackupHelper),
 };
 
diff --git a/core/jni/android_backup_BackupDataOutput.cpp b/core/jni/android_backup_BackupDataOutput.cpp
new file mode 100644
index 0000000..8fce2a2
--- /dev/null
+++ b/core/jni/android_backup_BackupDataOutput.cpp
@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2009 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "FileBackupHelper_native"
+#include <utils/Log.h>
+
+#include "JNIHelp.h"
+#include <android_runtime/AndroidRuntime.h>
+
+#include <utils/backup_helpers.h>
+
+namespace android
+{
+
+static jfieldID s_descriptorField = 0;
+
+static int
+ctor_native(JNIEnv* env, jobject This, jobject fileDescriptor)
+{
+    int err;
+
+    int fd = env->GetIntField(fileDescriptor, s_descriptorField);
+    if (fd == -1) {
+        return NULL;
+    }
+
+    return (int)new BackupDataWriter(fd);
+}
+
+static void
+dtor_native(JNIEnv* env, jobject This, int fd)
+{
+    delete (BackupDataWriter*)fd;
+}
+
+static const JNINativeMethod g_methods[] = {
+    { "ctor", "(Ljava/io/FileDescriptor;)I", (void*)ctor_native },
+    { "dtor", "(I)V", (void*)dtor_native },
+};
+
+int register_android_backup_BackupDataOutput(JNIEnv* env)
+{
+    LOGD("register_android_backup_BackupDataOutput");
+
+    jclass clazz;
+
+    clazz = env->FindClass("java/io/FileDescriptor");
+    LOG_FATAL_IF(clazz == NULL, "Unable to find class java.io.FileDescriptor");
+    s_descriptorField = env->GetFieldID(clazz, "descriptor", "I");
+    LOG_FATAL_IF(s_descriptorField == NULL,
+            "Unable to find descriptor field in java.io.FileDescriptor");
+
+    return AndroidRuntime::registerNativeMethods(env, "android/backup/BackupDataOutput",
+            g_methods, NELEM(g_methods));
+}
+
+}
diff --git a/core/jni/android_backup_FileBackupHelper.cpp b/core/jni/android_backup_FileBackupHelper.cpp
index c6de3a5..a05d812 100644
--- a/core/jni/android_backup_FileBackupHelper.cpp
+++ b/core/jni/android_backup_FileBackupHelper.cpp
@@ -28,7 +28,7 @@ namespace android
 static jfieldID s_descriptorField = 0;
 
 static int
-performBackup_native(JNIEnv* env, jobject clazz, jstring basePath, jobject oldState, jobject data,
+performBackup_native(JNIEnv* env, jobject clazz, jstring basePath, jobject oldState, int data,
         jobject newState, jobjectArray files)
 {
     int err;
@@ -37,7 +37,7 @@ performBackup_native(JNIEnv* env, jobject clazz, jstring basePath, jobject oldSt
     LOGD("oldState=%p newState=%p data=%p\n", oldState, newState, data);
     int oldStateFD = oldState != NULL ? env->GetIntField(oldState, s_descriptorField) : -1;
     int newStateFD = env->GetIntField(newState, s_descriptorField);
-    int dataFD = env->GetIntField(data, s_descriptorField);
+    BackupDataWriter* dataStream = (BackupDataWriter*)data;
 
     char const* basePathUTF = env->GetStringUTFChars(basePath, NULL);
     LOGD("basePathUTF=\"%s\"\n", basePathUTF);
@@ -47,7 +47,7 @@ performBackup_native(JNIEnv* env, jobject clazz, jstring basePath, jobject oldSt
         filesUTF[i] = env->GetStringUTFChars((jstring)env->GetObjectArrayElement(files, i), NULL);
     }
 
-    err = back_up_files(oldStateFD, dataFD, newStateFD, basePathUTF, filesUTF, fileCount);
+    err = back_up_files(oldStateFD, dataStream, newStateFD, basePathUTF, filesUTF, fileCount);
 
     for (int i=0; i<fileCount; i++) {
         env->ReleaseStringUTFChars((jstring)env->GetObjectArrayElement(files, i), filesUTF[i]);
@@ -60,8 +60,7 @@ performBackup_native(JNIEnv* env, jobject clazz, jstring basePath, jobject oldSt
 
 static const JNINativeMethod g_methods[] = {
     { "performBackup_native",
-        "(Ljava/lang/String;Ljava/io/FileDescriptor;Ljava/io/FileDescriptor;"
-        "Ljava/io/FileDescriptor;[Ljava/lang/String;)I",
+        "(Ljava/lang/String;Ljava/io/FileDescriptor;ILjava/io/FileDescriptor;[Ljava/lang/String;)I",
         (void*)performBackup_native },
 };
 
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 @@ public:
     ~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 @@ private:
     } 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 @@ namespace android {
  *      - 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 @@ BackupDataWriter::WriteAppHeader(const String8& packageName, int cookie)
 
     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 @@ BackupDataWriter::WriteEntityHeader(const String8& key, size_t dataSize)
 
     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 @@ BackupDataWriter::WriteAppFooter(int cookie)
     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 @@ BackupDataReader::Status()
     } while(0)
 
 status_t
-BackupDataReader::ReadNextHeader()
+BackupDataReader::ReadNextHeader(int* type)
 {
     if (m_status != NO_ERROR) {
         return m_status;
@@ -280,7 +276,7 @@ BackupDataReader::ReadNextHeader()
     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 @@ BackupDataReader::ReadNextHeader()
             }
             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 @@ BackupDataReader::ReadNextHeader()
                 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 @@ BackupDataReader::ReadNextHeader()
             m_status = EINVAL;
     }
     m_pos += sizeof(m_header);
+    if (type) {
+        *type = m_header.type;
+    }
     
     return m_status;
 }
@@ -328,7 +322,7 @@ BackupDataReader::ReadAppHeader(String8* packageName, int* cookie)
     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 @@ BackupDataReader::ReadAppHeader(String8* packageName, int* cookie)
 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 @@ BackupDataReader::ReadEntityHeader(String8* key, size_t* dataSize)
     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 @@ BackupDataReader::ReadEntityHeader(String8* key, size_t* dataSize)
 }
 
 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 @@ BackupDataReader::ReadAppFooter(int* cookie)
     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 @@ namespace android {
 #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 @@ write_snapshot_file(int fd, const KeyedVector<String8,FileState>& snapshot)
 }
 
 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;
-}
 
-static int
-compute_crc32(const String8& filename)
-{
     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);
 
-    int fd = open(filename.string(), O_RDONLY);
+    return NO_ERROR;
+}
+
+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) {
-        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);
     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 @@ back_up_files(int oldSnapshotFD, int oldDataStream, int newSnapshotFD,
         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 @@ back_up_files(int oldSnapshotFD, int oldDataStream, int newSnapshotFD,
             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);
-
-            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);
+            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("  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 @@ back_up_files(int oldSnapshotFD, int oldDataStream, int newSnapshotFD,
 
     // these were deleted
     while (n<N) {
-        write_delete_file(oldSnapshot.keyAt(n));
+        dataStream->WriteEntityHeader(oldSnapshot.keyAt(n), -1);
         n++;
     }
 
@@ -311,7 +384,7 @@ back_up_files(int oldSnapshotFD, int oldDataStream, int newSnapshotFD,
         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 @@ backup_helper_test_files()
         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 @@ backup_helper_test_files()
         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);
diff --git a/services/java/com/android/server/BackupManagerService.java b/services/java/com/android/server/BackupManagerService.java
index 983329b..e3fff81 100644
--- a/services/java/com/android/server/BackupManagerService.java
+++ b/services/java/com/android/server/BackupManagerService.java
@@ -158,11 +158,13 @@ class BackupManagerService extends IBackupManager.Stub {
             case MSG_RUN_BACKUP:
                 // snapshot the pending-backup set and work on that
                 synchronized (mQueueLock) {
-                    mBackupQueue = new ArrayList();
-                    for (BackupRequest b: mPendingBackups.values()) {
-                        mBackupQueue.add(b);
+                    if (mBackupQueue == null) {
+                        mBackupQueue = new ArrayList();
+                        for (BackupRequest b: mPendingBackups.values()) {
+                            mBackupQueue.add(b);
+                        }
+                        mPendingBackups = new HashMap<ComponentName,BackupRequest>();
                     }
-                    mPendingBackups = new HashMap<ComponentName,BackupRequest>();
                     // !!! TODO: start a new backup-queue journal file too
                     // WARNING: If we crash after this line, anything in mPendingBackups will
                     // be lost.  FIX THIS.
@@ -190,9 +192,13 @@ class BackupManagerService extends IBackupManager.Stub {
             BackupRequest request;
             synchronized (mQueueLock) {
                 int queueSize = mBackupQueue.size();
+                Log.d(TAG, "mBackupQueue.size=" + queueSize);
                 if (queueSize == 0) {
                     mBackupQueue = null;
-                    // TODO: Anything else to do here?
+                    // if there are pending backups, start those after a short delay
+                    if (mPendingBackups.size() > 0) {
+                        mBackupHandler.sendEmptyMessageDelayed(MSG_RUN_BACKUP, COLLECTION_INTERVAL);
+                    }
                     return;
                 }
                 request = mBackupQueue.get(0);
@@ -267,7 +273,7 @@ class BackupManagerService extends IBackupManager.Stub {
             
             // !!! TODO: After successful transport, delete the now-stale data
             // and juggle the files so that next time the new state is passed
-            backupDataName.delete();
+            //backupDataName.delete();
             newStateName.renameTo(savedStateName);
             
         } catch (FileNotFoundException fnf) {
@@ -284,6 +290,9 @@ class BackupManagerService extends IBackupManager.Stub {
             mBackupQueue.remove(0);
         }
         mContext.unbindService(mBackupHandler);
+
+        // start the next one
+        startOneService();
     }
 
     // Add the backup services in the given package to our set of known backup participants.
diff --git a/tests/backup/Android.mk b/tests/backup/Android.mk
index 2e3385f..0813c35 100644
--- a/tests/backup/Android.mk
+++ b/tests/backup/Android.mk
@@ -21,7 +21,7 @@ include $(CLEAR_VARS)
 LOCAL_SRC_FILES := \
     backup_helper_test.cpp
  
-LOCAL_MODULE_TAGS := user
+LOCAL_MODULE_TAGS := optional
 LOCAL_MODULE := backup_helper_test
 LOCAL_SHARED_LIBRARIES := libutils
 
@@ -31,7 +31,7 @@ include $(BUILD_EXECUTABLE)
 # ========================================
 include $(CLEAR_VARS)
 
-LOCAL_MODULE_TAGS := user
+LOCAL_MODULE_TAGS := optional
 
 LOCAL_SRC_FILES := $(call all-subdir-java-files)