1 /*
2  * Copyright (C) 2010 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 "MtpRequestPacket"
18 
19 #include <stdio.h>
20 #include <sys/types.h>
21 #include <fcntl.h>
22 
23 #include "IMtpHandle.h"
24 #include "MtpRequestPacket.h"
25 
26 #include <usbhost/usbhost.h>
27 
28 namespace android {
29 
MtpRequestPacket()30 MtpRequestPacket::MtpRequestPacket()
31     :   MtpPacket(512),
32         mParameterCount(0)
33 {
34 }
35 
~MtpRequestPacket()36 MtpRequestPacket::~MtpRequestPacket() {
37 }
38 
39 #ifdef MTP_DEVICE
read(IMtpHandle * h)40 int MtpRequestPacket::read(IMtpHandle *h) {
41     int ret = h->read(mBuffer, mBufferSize);
42     if (ret < 0) {
43         // file read error
44         return ret;
45     }
46 
47     // request packet should have 12 byte header followed by 0 to 5 32-bit arguments
48     const size_t read_size = static_cast<size_t>(ret);
49     if (read_size >= MTP_CONTAINER_HEADER_SIZE
50             && read_size <= MTP_CONTAINER_HEADER_SIZE + 5 * sizeof(uint32_t)
51             && ((read_size - MTP_CONTAINER_HEADER_SIZE) & 3) == 0) {
52         mPacketSize = read_size;
53         mParameterCount = (read_size - MTP_CONTAINER_HEADER_SIZE) / sizeof(uint32_t);
54     } else {
55         ALOGE("Malformed MTP request packet");
56         ret = -1;
57     }
58     return ret;
59 }
60 #endif
61 
62 #ifdef MTP_HOST
63     // write our buffer to the given endpoint (host mode)
write(struct usb_request * request)64 int MtpRequestPacket::write(struct usb_request *request)
65 {
66     putUInt32(MTP_CONTAINER_LENGTH_OFFSET, mPacketSize);
67     putUInt16(MTP_CONTAINER_TYPE_OFFSET, MTP_CONTAINER_TYPE_COMMAND);
68     request->buffer = mBuffer;
69     request->buffer_length = mPacketSize;
70     return transfer(request);
71 }
72 #endif
73 
74 }  // namespace android
75