android_backup_BackupDataInput.cpp revision 2fdd428e0f18384160f7c38ce3a2cd9ba7e7b2c2 
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
28// java.io.FileDescriptor
29static jfieldID s_descriptorField = 0;
30
31// android.backup.BackupDataInput$EntityHeader
32static jfieldID s_keyField = 0;
33static jfieldID s_dataSizeField = 0;
34
35static int
36ctor_native(JNIEnv* env, jobject clazz, jobject fileDescriptor)
37{
38    int err;
39
40    int fd = env->GetIntField(fileDescriptor, s_descriptorField);
41    if (fd == -1) {
42        return NULL;
43    }
44
45    return (int)new BackupDataReader(fd);
46}
47
48static void
49dtor_native(JNIEnv* env, jobject clazz, int r)
50{
51    delete (BackupDataReader*)r;
52}
53
54static jint
55readNextHeader_native(JNIEnv* env, jobject clazz, int r, jobject entity)
56{
57    int err;
58    BackupDataReader* reader = (BackupDataReader*)r;
59
60    err = reader->Status();
61    if (err != 0) {
62        return err < 0 ? err : -1;
63    }
64
65    int type = 0;
66
67    err = reader->ReadNextHeader(&type);
68    if (err == EIO) {
69        // Clean EOF with no footer block; just claim we're done
70        return 1;
71    }
72
73    if (err != 0) {
74        return err < 0 ? err : -1;
75    }
76
77    switch (type) {
78    case BACKUP_HEADER_APP_V1:
79    {
80        String8 packageName;
81        int cookie;
82        err = reader->ReadAppHeader(&packageName, &cookie);
83        if (err != 0) {
84            LOGD("ReadAppHeader() returned %d; aborting", err);
85            return err < 0 ? err : -1;
86        }
87        break;
88    }
89    case BACKUP_HEADER_ENTITY_V1:
90    {
91        String8 key;
92        size_t dataSize;
93        err = reader->ReadEntityHeader(&key, &dataSize);
94        if (err != 0) {
95            LOGD("ReadEntityHeader(); aborting", err);
96            return err < 0 ? err : -1;
97        }
98        // TODO: Set the fields in the entity object
99        jstring keyStr = env->NewStringUTF(key.string());
100        env->SetObjectField(entity, s_keyField, keyStr);
101        env->SetIntField(entity, s_dataSizeField, dataSize);
102        return 0;
103    }
104    case BACKUP_FOOTER_APP_V1:
105    {
106        break;
107    }
108    default:
109        LOGD("Unknown header type: 0x%08x\n", type);
110        return -1;
111    }
112
113    // done
114    return 1;
115}
116
117static jint
118readEntityData_native(JNIEnv* env, jobject clazz, int r, jbyteArray data, int size)
119{
120    int err;
121    BackupDataReader* reader = (BackupDataReader*)r;
122
123    if (env->GetArrayLength(data) < size) {
124        // size mismatch
125        return -1;
126    }
127
128    jbyte* dataBytes = env->GetByteArrayElements(data, NULL);
129    if (dataBytes == NULL) {
130        return -2;
131    }
132
133    err = reader->ReadEntityData(dataBytes, size);
134
135    env->ReleaseByteArrayElements(data, dataBytes, 0);
136
137    return err;
138}
139
140static const JNINativeMethod g_methods[] = {
141    { "ctor", "(Ljava/io/FileDescriptor;)I", (void*)ctor_native },
142    { "dtor", "(I)V", (void*)dtor_native },
143    { "readNextHeader_native", "(ILandroid/backup/BackupDataInput$EntityHeader;)I",
144            (void*)readNextHeader_native },
145    { "readEntityData_native", "(I[BI)I", (void*)readEntityData_native },
146};
147
148int register_android_backup_BackupDataInput(JNIEnv* env)
149{
150    //LOGD("register_android_backup_BackupDataInput");
151
152    jclass clazz;
153
154    clazz = env->FindClass("java/io/FileDescriptor");
155    LOG_FATAL_IF(clazz == NULL, "Unable to find class java.io.FileDescriptor");
156    s_descriptorField = env->GetFieldID(clazz, "descriptor", "I");
157    LOG_FATAL_IF(s_descriptorField == NULL,
158            "Unable to find descriptor field in java.io.FileDescriptor");
159
160    clazz = env->FindClass("android/backup/BackupDataInput$EntityHeader");
161    LOG_FATAL_IF(clazz == NULL, "Unable to find class android.backup.BackupDataInput.EntityHeader");
162    s_keyField = env->GetFieldID(clazz, "key", "Ljava/lang/String;");
163    LOG_FATAL_IF(s_keyField == NULL,
164            "Unable to find key field in android.backup.BackupDataInput.EntityHeader");
165    s_dataSizeField = env->GetFieldID(clazz, "dataSize", "I");
166    LOG_FATAL_IF(s_dataSizeField == NULL,
167            "Unable to find dataSize field in android.backup.BackupDataInput.EntityHeader");
168
169    return AndroidRuntime::registerNativeMethods(env, "android/backup/BackupDataInput",
170            g_methods, NELEM(g_methods));
171}
172
173}
174