android_backup_BackupDataOutput.cpp revision 06290a4bb9b280fa14a2bbeb2d3ceb09396a78c3 
1/*
2 * Copyright (C) 2009 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#define LOG_TAG "FileBackupHelper_native"
18#include <utils/Log.h>
19
20#include "JNIHelp.h"
21#include <android_runtime/AndroidRuntime.h>
22
23#include <utils/BackupHelpers.h>
24
25namespace android
26{
27
28static jfieldID s_descriptorField = 0;
29
30static int
31ctor_native(JNIEnv* env, jobject clazz, jobject fileDescriptor)
32{
33    int err;
34
35    int fd = env->GetIntField(fileDescriptor, s_descriptorField);
36    if (fd == -1) {
37        return NULL;
38    }
39
40    return (int)new BackupDataWriter(fd);
41}
42
43static void
44dtor_native(JNIEnv* env, jobject clazz, int w)
45{
46    delete (BackupDataWriter*)w;
47}
48
49static jint
50writeEntityHeader_native(JNIEnv* env, jobject clazz, int w, jstring key, int dataSize)
51{
52    int err;
53    BackupDataWriter* writer = (BackupDataWriter*)w;
54
55    const char* keyUTF = env->GetStringUTFChars(key, NULL);
56    if (keyUTF == NULL) {
57        return -1;
58    }
59
60    err = writer->WriteEntityHeader(String8(keyUTF), dataSize);
61
62    env->ReleaseStringUTFChars(key, keyUTF);
63
64    return err;
65}
66
67static jint
68writeEntityData_native(JNIEnv* env, jobject clazz, int w, jbyteArray data, int size)
69{
70    int err;
71    BackupDataWriter* writer = (BackupDataWriter*)w;
72
73    if (env->GetArrayLength(data) > size) {
74        // size mismatch
75        return -1;
76    }
77
78    jbyte* dataBytes = env->GetByteArrayElements(data, NULL);
79    if (dataBytes == NULL) {
80        return -1;
81    }
82
83    err = writer->WriteEntityData(dataBytes, size);
84
85    env->ReleaseByteArrayElements(data, dataBytes, JNI_ABORT);
86
87    return err;
88}
89
90static void
91setKeyPrefix_native(JNIEnv* env, jobject clazz, int w, jstring keyPrefixObj)
92{
93    int err;
94    BackupDataWriter* writer = (BackupDataWriter*)w;
95
96    const char* keyPrefixUTF = env->GetStringUTFChars(keyPrefixObj, NULL);
97    String8 keyPrefix(keyPrefixUTF ? keyPrefixUTF : "");
98
99    writer->SetKeyPrefix(keyPrefix);
100
101    env->ReleaseStringUTFChars(keyPrefixObj, keyPrefixUTF);
102}
103
104static const JNINativeMethod g_methods[] = {
105    { "ctor", "(Ljava/io/FileDescriptor;)I", (void*)ctor_native },
106    { "dtor", "(I)V", (void*)dtor_native },
107    { "writeEntityHeader_native", "(ILjava/lang/String;I)I", (void*)writeEntityHeader_native },
108    { "writeEntityData_native", "(I[BI)I", (void*)writeEntityData_native },
109    { "setKeyPrefix_native", "(ILjava/lang/String;)V", (void*)setKeyPrefix_native },
110};
111
112int register_android_backup_BackupDataOutput(JNIEnv* env)
113{
114    //LOGD("register_android_backup_BackupDataOutput");
115
116    jclass clazz;
117
118    clazz = env->FindClass("java/io/FileDescriptor");
119    LOG_FATAL_IF(clazz == NULL, "Unable to find class java.io.FileDescriptor");
120    s_descriptorField = env->GetFieldID(clazz, "descriptor", "I");
121    LOG_FATAL_IF(s_descriptorField == NULL,
122            "Unable to find descriptor field in java.io.FileDescriptor");
123
124    return AndroidRuntime::registerNativeMethods(env, "android/backup/BackupDataOutput",
125            g_methods, NELEM(g_methods));
126}
127
128}
129