1/*
2 * Copyright (C) 2006 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#include <unistd.h>
18#include <binder/IBinder.h>
19#include <binder/IServiceManager.h>
20#include <binder/Parcel.h>
21#include <utils/String8.h>
22
23#include "ActivityManager.h"
24
25namespace android {
26
27const uint32_t OPEN_CONTENT_URI_TRANSACTION = IBinder::FIRST_CALL_TRANSACTION + 4;
28
29// Perform ContentProvider.openFile() on the given URI, returning
30// the resulting native file descriptor.  Returns < 0 on error.
31int openContentProviderFile(const String16& uri)
32{
33    int fd = -1;
34
35    sp<IServiceManager> sm = defaultServiceManager();
36    sp<IBinder> am = sm->getService(String16("activity"));
37    if (am != NULL) {
38        Parcel data, reply;
39        data.writeInterfaceToken(String16("android.app.IActivityManager"));
40        data.writeString16(uri);
41        status_t ret = am->transact(OPEN_CONTENT_URI_TRANSACTION, data, &reply);
42        if (ret == NO_ERROR) {
43            int32_t exceptionCode = reply.readExceptionCode();
44            if (!exceptionCode) {
45                // Success is indicated here by a nonzero int followed by the fd;
46                // failure by a zero int with no data following.
47                if (reply.readInt32() != 0) {
48                    fd = dup(reply.readFileDescriptor());
49                }
50            } else {
51                // An exception was thrown back; fall through to return failure
52                ALOGD("openContentUri(%s) caught exception %d\n",
53                        String8(uri).string(), exceptionCode);
54            }
55        }
56    }
57
58    return fd;
59}
60
61} /* namespace android */
62