/*
|
* 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 "BackupHelperDispatcher_native"
|
#include <utils/Log.h>
|
|
#include <nativehelper/JNIHelp.h>
|
#include <android_runtime/AndroidRuntime.h>
|
|
#include <sys/types.h>
|
#include <sys/uio.h>
|
#include <unistd.h>
|
|
#include "core_jni_helpers.h"
|
|
#define VERSION_1_HEADER 0x01706c48 // 'Hlp'1 little endian
|
|
namespace android
|
{
|
|
struct chunk_header_v1 {
|
int headerSize;
|
int version;
|
int dataSize; // corresponds to Header.chunkSize
|
int nameLength; // not including the NULL terminator, which is not written to the file
|
};
|
|
static jfieldID s_chunkSizeField = 0;
|
static jfieldID s_keyPrefixField = 0;
|
|
static jint
|
readHeader_native(JNIEnv* env, jobject clazz, jobject headerObj, jobject fdObj)
|
{
|
chunk_header_v1 flattenedHeader;
|
ssize_t amt;
|
String8 keyPrefix;
|
char* buf;
|
|
int fd = jniGetFDFromFileDescriptor(env, fdObj);
|
|
amt = read(fd, &flattenedHeader.headerSize, sizeof(flattenedHeader.headerSize));
|
if (amt != sizeof(flattenedHeader.headerSize)) {
|
return (jint) -1;
|
}
|
|
int remainingHeader = flattenedHeader.headerSize - sizeof(flattenedHeader.headerSize);
|
|
if (flattenedHeader.headerSize < (int)sizeof(chunk_header_v1)) {
|
ALOGW("Skipping unknown header: %d bytes", flattenedHeader.headerSize);
|
if (remainingHeader > 0) {
|
lseek(fd, remainingHeader, SEEK_CUR);
|
// >0 means skip this chunk
|
return (jint) 1;
|
}
|
}
|
|
amt = read(fd, &flattenedHeader.version,
|
sizeof(chunk_header_v1)-sizeof(flattenedHeader.headerSize));
|
if (amt <= 0) {
|
ALOGW("Failed reading chunk header");
|
return (jint) -1;
|
}
|
remainingHeader -= sizeof(chunk_header_v1)-sizeof(flattenedHeader.headerSize);
|
|
if (flattenedHeader.version != VERSION_1_HEADER) {
|
ALOGW("Skipping unknown header version: 0x%08x, %d bytes", flattenedHeader.version,
|
flattenedHeader.headerSize);
|
if (remainingHeader > 0) {
|
lseek(fd, remainingHeader, SEEK_CUR);
|
// >0 means skip this chunk
|
return (jint) 1;
|
}
|
}
|
|
#if 0
|
ALOGD("chunk header:");
|
ALOGD(" headerSize=%d", flattenedHeader.headerSize);
|
ALOGD(" version=0x%08x", flattenedHeader.version);
|
ALOGD(" dataSize=%d", flattenedHeader.dataSize);
|
ALOGD(" nameLength=%d", flattenedHeader.nameLength);
|
#endif
|
|
if (flattenedHeader.dataSize < 0 || flattenedHeader.nameLength < 0 ||
|
remainingHeader < flattenedHeader.nameLength) {
|
ALOGW("Malformed V1 header remainingHeader=%d dataSize=%d nameLength=%d", remainingHeader,
|
flattenedHeader.dataSize, flattenedHeader.nameLength);
|
return (jint) -1;
|
}
|
|
buf = keyPrefix.lockBuffer(flattenedHeader.nameLength);
|
if (buf == NULL) {
|
ALOGW("unable to allocate %d bytes", flattenedHeader.nameLength);
|
return (jint) -1;
|
}
|
|
amt = read(fd, buf, flattenedHeader.nameLength);
|
buf[flattenedHeader.nameLength] = 0;
|
|
keyPrefix.unlockBuffer(flattenedHeader.nameLength);
|
|
remainingHeader -= flattenedHeader.nameLength;
|
|
if (remainingHeader > 0) {
|
lseek(fd, remainingHeader, SEEK_CUR);
|
}
|
|
env->SetIntField(headerObj, s_chunkSizeField, flattenedHeader.dataSize);
|
env->SetObjectField(headerObj, s_keyPrefixField, env->NewStringUTF(keyPrefix.string()));
|
|
return (jint) 0;
|
}
|
|
static jint
|
skipChunk_native(JNIEnv* env, jobject clazz, jobject fdObj, jint bytesToSkip)
|
{
|
int fd = jniGetFDFromFileDescriptor(env, fdObj);
|
|
lseek(fd, bytesToSkip, SEEK_CUR);
|
|
return (jint) 0;
|
}
|
|
static int
|
padding_len(int len)
|
{
|
len = len % 4;
|
return len == 0 ? len : 4 - len;
|
}
|
|
static jint
|
allocateHeader_native(JNIEnv* env, jobject clazz, jobject headerObj, jobject fdObj)
|
{
|
int pos;
|
jstring nameObj;
|
int nameLength;
|
int namePadding;
|
int headerSize;
|
|
int fd = jniGetFDFromFileDescriptor(env, fdObj);
|
|
nameObj = (jstring)env->GetObjectField(headerObj, s_keyPrefixField);
|
|
nameLength = env->GetStringUTFLength(nameObj);
|
namePadding = padding_len(nameLength);
|
|
headerSize = sizeof(chunk_header_v1) + nameLength + namePadding;
|
|
pos = lseek(fd, 0, SEEK_CUR);
|
|
lseek(fd, headerSize, SEEK_CUR);
|
|
return (jint) pos;
|
}
|
|
static jint
|
writeHeader_native(JNIEnv* env, jobject clazz, jobject headerObj, jobject fdObj, jint pos)
|
{
|
int err;
|
chunk_header_v1 header;
|
int namePadding;
|
int prevPos;
|
jstring nameObj;
|
const char* buf;
|
|
int fd = jniGetFDFromFileDescriptor(env, fdObj);
|
prevPos = lseek(fd, 0, SEEK_CUR);
|
|
nameObj = (jstring)env->GetObjectField(headerObj, s_keyPrefixField);
|
header.nameLength = env->GetStringUTFLength(nameObj);
|
namePadding = padding_len(header.nameLength);
|
|
header.headerSize = sizeof(chunk_header_v1) + header.nameLength + namePadding;
|
header.version = VERSION_1_HEADER;
|
header.dataSize = prevPos - (pos + header.headerSize);
|
|
lseek(fd, pos, SEEK_SET);
|
err = write(fd, &header, sizeof(chunk_header_v1));
|
if (err != sizeof(chunk_header_v1)) {
|
return (jint) errno;
|
}
|
|
buf = env->GetStringUTFChars(nameObj, NULL);
|
err = write(fd, buf, header.nameLength);
|
env->ReleaseStringUTFChars(nameObj, buf);
|
if (err != header.nameLength) {
|
return (jint) errno;
|
}
|
|
if (namePadding != 0) {
|
int zero = 0;
|
err = write(fd, &zero, namePadding);
|
if (err != namePadding) {
|
return (jint) errno;
|
}
|
}
|
|
lseek(fd, prevPos, SEEK_SET);
|
return (jint) 0;
|
}
|
|
static const JNINativeMethod g_methods[] = {
|
{ "readHeader_native",
|
"(Landroid/app/backup/BackupHelperDispatcher$Header;Ljava/io/FileDescriptor;)I",
|
(void*)readHeader_native },
|
{ "skipChunk_native",
|
"(Ljava/io/FileDescriptor;I)I",
|
(void*)skipChunk_native },
|
{ "allocateHeader_native",
|
"(Landroid/app/backup/BackupHelperDispatcher$Header;Ljava/io/FileDescriptor;)I",
|
(void*)allocateHeader_native },
|
{ "writeHeader_native",
|
"(Landroid/app/backup/BackupHelperDispatcher$Header;Ljava/io/FileDescriptor;I)I",
|
(void*)writeHeader_native },
|
};
|
|
int register_android_backup_BackupHelperDispatcher(JNIEnv* env)
|
{
|
jclass clazz = FindClassOrDie(env, "android/app/backup/BackupHelperDispatcher$Header");
|
s_chunkSizeField = GetFieldIDOrDie(env, clazz, "chunkSize", "I");
|
s_keyPrefixField = GetFieldIDOrDie(env, clazz, "keyPrefix", "Ljava/lang/String;");
|
|
return RegisterMethodsOrDie(env, "android/app/backup/BackupHelperDispatcher", g_methods,
|
NELEM(g_methods));
|
}
|
|
}
|
