Implement the C++ class to write the backed up file data.

2 files changed, 76 insertions, 10 deletions

diff --git a/include/utils/ByteOrder.h b/include/utils/ByteOrder.h
index 4c06067..baa3a83 100644
--- a/include/utils/ByteOrder.h
+++ b/include/utils/ByteOrder.h
@@ -38,6 +38,16 @@
  * intent is to allow us to avoid byte swapping on the device.
  */
 
+static inline uint32_t android_swap_long(uint32_t v)
+{
+    return (v<<24) | ((v<<8)&0x00FF0000) | ((v>>8)&0x0000FF00) | (v>>24);
+}
+
+static inline uint16_t android_swap_short(uint16_t v)
+{
+    return (v<<8) | (v>>8);
+}
+
 #define DEVICE_BYTE_ORDER LITTLE_ENDIAN
 
 #if BYTE_ORDER == DEVICE_BYTE_ORDER
@@ -49,16 +59,6 @@
 
 #else
 
-static inline uint32_t android_swap_long(uint32_t v)
-{
-    return (v<<24) | ((v<<8)&0x00FF0000) | ((v>>8)&0x0000FF00) | (v>>24);
-}
-
-static inline uint16_t android_swap_short(uint16_t v)
-{
-    return (v<<8) | (v>>8);
-}
-
 #define	dtohl(x)	(android_swap_long(x))
 #define	dtohs(x)	(android_swap_short(x))
 #define	htodl(x)	(android_swap_long(x))
@@ -66,4 +66,16 @@ static inline uint16_t android_swap_short(uint16_t v)
 
 #endif
 
+#if BYTE_ORDER == LITTLE_ENDIAN
+#define fromlel(x) (x)
+#define fromles(x) (x)
+#define tolel(x) (x)
+#define toles(x) (x)
+#else
+#define fromlel(x) (android_swap_long(x))
+#define fromles(x) (android_swap_short(x))
+#define tolel(x) (android_swap_long(x))
+#define toles(x) (android_swap_short(x))
+#endif
+
 #endif // _LIBS_UTILS_BYTE_ORDER_H
diff --git a/include/utils/backup_helpers.h b/include/utils/backup_helpers.h
index 137c5f1..73b9989 100644
--- a/include/utils/backup_helpers.h
+++ b/include/utils/backup_helpers.h
@@ -1,15 +1,69 @@
+/*
+ * 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.
+ */
+
 #ifndef _UTILS_BACKUP_HELPERS_H
 #define _UTILS_BACKUP_HELPERS_H
 
+#include <utils/Errors.h>
+#include <utils/String8.h>
+
+namespace android {
+
 int back_up_files(int oldSnapshotFD, int oldDataStream, int newSnapshotFD,
         char const* fileBase, char const* const* files, int fileCount);
 
+/**
+ * Reads the data.
+ *
+ * If an error occurs, it poisons this object and all write calls will fail
+ * with the error that occurred.
+ */
+class BackupDataWriter
+{
+public:
+    BackupDataWriter(int fd);
+    // does not close fd
+    ~BackupDataWriter();
+
+    status_t WriteAppHeader(const String8& packageName);
+
+    status_t WriteEntityHeader(const String8& key, size_t dataSize);
+    status_t WriteEntityData(const void* data, size_t size);
+
+    status_t WriteAppFooter();
+
+private:
+    explicit BackupDataWriter();
+    status_t write_padding_for(int n);
+    
+    int m_fd;
+    status_t m_status;
+    ssize_t m_pos;
+    int m_entityCount;
+};
+
 #define TEST_BACKUP_HELPERS 0
 
 #if TEST_BACKUP_HELPERS
 int backup_helper_test_empty();
 int backup_helper_test_four();
 int backup_helper_test_files();
+int backup_helper_test_data_writer();
 #endif
 
+} // namespace android
+
 #endif // _UTILS_BACKUP_HELPERS_H