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      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 "MtpDevice"
     18 
     19 #include "MtpDebug.h"
     20 #include "MtpDevice.h"
     21 #include "MtpDeviceInfo.h"
     22 #include "MtpEventPacket.h"
     23 #include "MtpObjectInfo.h"
     24 #include "MtpProperty.h"
     25 #include "MtpStorageInfo.h"
     26 #include "MtpStringBuffer.h"
     27 #include "MtpUtils.h"
     28 
     29 #include <stdio.h>
     30 #include <stdlib.h>
     31 #include <sys/types.h>
     32 #include <sys/ioctl.h>
     33 #include <sys/stat.h>
     34 #include <fcntl.h>
     35 #include <errno.h>
     36 #include <endian.h>
     37 
     38 #include <usbhost/usbhost.h>
     39 
     40 namespace android {
     41 
     42 #if 0
     43 static bool isMtpDevice(uint16_t vendor, uint16_t product) {
     44     // Sandisk Sansa Fuze
     45     if (vendor == 0x0781 && product == 0x74c2)
     46         return true;
     47     // Samsung YP-Z5
     48     if (vendor == 0x04e8 && product == 0x503c)
     49         return true;
     50     return false;
     51 }
     52 #endif
     53 
     54 namespace {
     55 
     56 bool writeToFd(void* data, uint32_t /* unused_offset */, uint32_t length, void* clientData) {
     57     const int fd = *static_cast<int*>(clientData);
     58     const ssize_t result = write(fd, data, length);
     59     if (result < 0) {
     60         return false;
     61     }
     62     return static_cast<uint32_t>(result) == length;
     63 }
     64 
     65 }  // namespace
     66 
     67 MtpDevice* MtpDevice::open(const char* deviceName, int fd) {
     68     struct usb_device *device = usb_device_new(deviceName, fd);
     69     if (!device) {
     70         ALOGE("usb_device_new failed for %s", deviceName);
     71         return NULL;
     72     }
     73 
     74     struct usb_descriptor_header* desc;
     75     struct usb_descriptor_iter iter;
     76 
     77     usb_descriptor_iter_init(device, &iter);
     78 
     79     while ((desc = usb_descriptor_iter_next(&iter)) != NULL) {
     80         if (desc->bDescriptorType == USB_DT_INTERFACE) {
     81             struct usb_interface_descriptor *interface = (struct usb_interface_descriptor *)desc;
     82 
     83             if (interface->bInterfaceClass == USB_CLASS_STILL_IMAGE &&
     84                 interface->bInterfaceSubClass == 1 && // Still Image Capture
     85                 interface->bInterfaceProtocol == 1)     // Picture Transfer Protocol (PIMA 15470)
     86             {
     87                 char* manufacturerName = usb_device_get_manufacturer_name(device);
     88                 char* productName = usb_device_get_product_name(device);
     89                 ALOGD("Found camera: \"%s\" \"%s\"\n", manufacturerName, productName);
     90                 free(manufacturerName);
     91                 free(productName);
     92             } else if (interface->bInterfaceClass == 0xFF &&
     93                     interface->bInterfaceSubClass == 0xFF &&
     94                     interface->bInterfaceProtocol == 0) {
     95                 char* interfaceName = usb_device_get_string(device, interface->iInterface);
     96                 if (!interfaceName) {
     97                     continue;
     98                 } else if (strcmp(interfaceName, "MTP")) {
     99                     free(interfaceName);
    100                     continue;
    101                 }
    102                 free(interfaceName);
    103 
    104                 // Looks like an android style MTP device
    105                 char* manufacturerName = usb_device_get_manufacturer_name(device);
    106                 char* productName = usb_device_get_product_name(device);
    107                 ALOGD("Found MTP device: \"%s\" \"%s\"\n", manufacturerName, productName);
    108                 free(manufacturerName);
    109                 free(productName);
    110             }
    111 #if 0
    112              else {
    113                 // look for special cased devices based on vendor/product ID
    114                 // we are doing this mainly for testing purposes
    115                 uint16_t vendor = usb_device_get_vendor_id(device);
    116                 uint16_t product = usb_device_get_product_id(device);
    117                 if (!isMtpDevice(vendor, product)) {
    118                     // not an MTP or PTP device
    119                     continue;
    120                 }
    121                 // request MTP OS string and descriptor
    122                 // some music players need to see this before entering MTP mode.
    123                 char buffer[256];
    124                 memset(buffer, 0, sizeof(buffer));
    125                 int ret = usb_device_control_transfer(device,
    126                         USB_DIR_IN|USB_RECIP_DEVICE|USB_TYPE_STANDARD,
    127                         USB_REQ_GET_DESCRIPTOR, (USB_DT_STRING << 8) | 0xEE,
    128                         0, buffer, sizeof(buffer), 0);
    129                 printf("usb_device_control_transfer returned %d errno: %d\n", ret, errno);
    130                 if (ret > 0) {
    131                     printf("got MTP string %s\n", buffer);
    132                     ret = usb_device_control_transfer(device,
    133                             USB_DIR_IN|USB_RECIP_DEVICE|USB_TYPE_VENDOR, 1,
    134                             0, 4, buffer, sizeof(buffer), 0);
    135                     printf("OS descriptor got %d\n", ret);
    136                 } else {
    137                     printf("no MTP string\n");
    138                 }
    139             }
    140 #else
    141             else {
    142                 continue;
    143             }
    144 #endif
    145             // if we got here, then we have a likely MTP or PTP device
    146 
    147             // interface should be followed by three endpoints
    148             struct usb_endpoint_descriptor *ep;
    149             struct usb_endpoint_descriptor *ep_in_desc = NULL;
    150             struct usb_endpoint_descriptor *ep_out_desc = NULL;
    151             struct usb_endpoint_descriptor *ep_intr_desc = NULL;
    152             //USB3 add USB_DT_SS_ENDPOINT_COMP as companion descriptor;
    153             struct usb_ss_ep_comp_descriptor *ep_ss_ep_comp_desc = NULL;
    154             for (int i = 0; i < 3; i++) {
    155                 ep = (struct usb_endpoint_descriptor *)usb_descriptor_iter_next(&iter);
    156                 if (ep && ep->bDescriptorType == USB_DT_SS_ENDPOINT_COMP) {
    157                     ALOGD("Descriptor type is USB_DT_SS_ENDPOINT_COMP for USB3 \n");
    158                     ep_ss_ep_comp_desc = (usb_ss_ep_comp_descriptor*)ep;
    159                     ep = (struct usb_endpoint_descriptor *)usb_descriptor_iter_next(&iter);
    160                  }
    161 
    162                 if (!ep || ep->bDescriptorType != USB_DT_ENDPOINT) {
    163                     ALOGE("endpoints not found\n");
    164                     usb_device_close(device);
    165                     return NULL;
    166                 }
    167 
    168                 if (ep->bmAttributes == USB_ENDPOINT_XFER_BULK) {
    169                     if (ep->bEndpointAddress & USB_ENDPOINT_DIR_MASK)
    170                         ep_in_desc = ep;
    171                     else
    172                         ep_out_desc = ep;
    173                 } else if (ep->bmAttributes == USB_ENDPOINT_XFER_INT &&
    174                     ep->bEndpointAddress & USB_ENDPOINT_DIR_MASK) {
    175                     ep_intr_desc = ep;
    176                 }
    177             }
    178             if (!ep_in_desc || !ep_out_desc || !ep_intr_desc) {
    179                 ALOGE("endpoints not found\n");
    180                 usb_device_close(device);
    181                 return NULL;
    182             }
    183 
    184             int ret = usb_device_claim_interface(device, interface->bInterfaceNumber);
    185             if (ret && errno == EBUSY) {
    186                 // disconnect kernel driver and try again
    187                 usb_device_connect_kernel_driver(device, interface->bInterfaceNumber, false);
    188                 ret = usb_device_claim_interface(device, interface->bInterfaceNumber);
    189             }
    190             if (ret) {
    191                 ALOGE("usb_device_claim_interface failed errno: %d\n", errno);
    192                 usb_device_close(device);
    193                 return NULL;
    194             }
    195 
    196             MtpDevice* mtpDevice = new MtpDevice(device, interface->bInterfaceNumber,
    197                         ep_in_desc, ep_out_desc, ep_intr_desc);
    198             mtpDevice->initialize();
    199             return mtpDevice;
    200         }
    201     }
    202 
    203     usb_device_close(device);
    204     ALOGE("device not found");
    205     return NULL;
    206 }
    207 
    208 MtpDevice::MtpDevice(struct usb_device* device, int interface,
    209             const struct usb_endpoint_descriptor *ep_in,
    210             const struct usb_endpoint_descriptor *ep_out,
    211             const struct usb_endpoint_descriptor *ep_intr)
    212     :   mDevice(device),
    213         mInterface(interface),
    214         mRequestIn1(NULL),
    215         mRequestIn2(NULL),
    216         mRequestOut(NULL),
    217         mRequestIntr(NULL),
    218         mDeviceInfo(NULL),
    219         mSessionID(0),
    220         mTransactionID(0),
    221         mReceivedResponse(false),
    222         mProcessingEvent(false),
    223         mCurrentEventHandle(0)
    224 {
    225     mRequestIn1 = usb_request_new(device, ep_in);
    226     mRequestIn2 = usb_request_new(device, ep_in);
    227     mRequestOut = usb_request_new(device, ep_out);
    228     mRequestIntr = usb_request_new(device, ep_intr);
    229 }
    230 
    231 MtpDevice::~MtpDevice() {
    232     close();
    233     for (size_t i = 0; i < mDeviceProperties.size(); i++)
    234         delete mDeviceProperties[i];
    235     usb_request_free(mRequestIn1);
    236     usb_request_free(mRequestIn2);
    237     usb_request_free(mRequestOut);
    238     usb_request_free(mRequestIntr);
    239 }
    240 
    241 void MtpDevice::initialize() {
    242     openSession();
    243     mDeviceInfo = getDeviceInfo();
    244     if (mDeviceInfo) {
    245         if (mDeviceInfo->mDeviceProperties) {
    246             int count = mDeviceInfo->mDeviceProperties->size();
    247             for (int i = 0; i < count; i++) {
    248                 MtpDeviceProperty propCode = (*mDeviceInfo->mDeviceProperties)[i];
    249                 MtpProperty* property = getDevicePropDesc(propCode);
    250                 if (property)
    251                     mDeviceProperties.push(property);
    252             }
    253         }
    254     }
    255 }
    256 
    257 void MtpDevice::close() {
    258     if (mDevice) {
    259         usb_device_release_interface(mDevice, mInterface);
    260         usb_device_close(mDevice);
    261         mDevice = NULL;
    262     }
    263 }
    264 
    265 void MtpDevice::print() {
    266     if (mDeviceInfo) {
    267         mDeviceInfo->print();
    268 
    269         if (mDeviceInfo->mDeviceProperties) {
    270             ALOGI("***** DEVICE PROPERTIES *****\n");
    271             int count = mDeviceInfo->mDeviceProperties->size();
    272             for (int i = 0; i < count; i++) {
    273                 MtpDeviceProperty propCode = (*mDeviceInfo->mDeviceProperties)[i];
    274                 MtpProperty* property = getDevicePropDesc(propCode);
    275                 if (property) {
    276                     property->print();
    277                     delete property;
    278                 }
    279             }
    280         }
    281     }
    282 
    283     if (mDeviceInfo->mPlaybackFormats) {
    284             ALOGI("***** OBJECT PROPERTIES *****\n");
    285         int count = mDeviceInfo->mPlaybackFormats->size();
    286         for (int i = 0; i < count; i++) {
    287             MtpObjectFormat format = (*mDeviceInfo->mPlaybackFormats)[i];
    288             ALOGI("*** FORMAT: %s\n", MtpDebug::getFormatCodeName(format));
    289             MtpObjectPropertyList* props = getObjectPropsSupported(format);
    290             if (props) {
    291                 for (size_t j = 0; j < props->size(); j++) {
    292                     MtpObjectProperty prop = (*props)[j];
    293                     MtpProperty* property = getObjectPropDesc(prop, format);
    294                     if (property) {
    295                         property->print();
    296                         delete property;
    297                     } else {
    298                         ALOGE("could not fetch property: %s",
    299                                 MtpDebug::getObjectPropCodeName(prop));
    300                     }
    301                 }
    302             }
    303         }
    304     }
    305 }
    306 
    307 const char* MtpDevice::getDeviceName() {
    308     if (mDevice)
    309         return usb_device_get_name(mDevice);
    310     else
    311         return "???";
    312 }
    313 
    314 bool MtpDevice::openSession() {
    315     Mutex::Autolock autoLock(mMutex);
    316 
    317     mSessionID = 0;
    318     mTransactionID = 0;
    319     MtpSessionID newSession = 1;
    320     mRequest.reset();
    321     mRequest.setParameter(1, newSession);
    322     if (!sendRequest(MTP_OPERATION_OPEN_SESSION))
    323         return false;
    324     MtpResponseCode ret = readResponse();
    325     if (ret == MTP_RESPONSE_SESSION_ALREADY_OPEN)
    326         newSession = mResponse.getParameter(1);
    327     else if (ret != MTP_RESPONSE_OK)
    328         return false;
    329 
    330     mSessionID = newSession;
    331     mTransactionID = 1;
    332     return true;
    333 }
    334 
    335 bool MtpDevice::closeSession() {
    336     // FIXME
    337     return true;
    338 }
    339 
    340 MtpDeviceInfo* MtpDevice::getDeviceInfo() {
    341     Mutex::Autolock autoLock(mMutex);
    342 
    343     mRequest.reset();
    344     if (!sendRequest(MTP_OPERATION_GET_DEVICE_INFO))
    345         return NULL;
    346     if (!readData())
    347         return NULL;
    348     MtpResponseCode ret = readResponse();
    349     if (ret == MTP_RESPONSE_OK) {
    350         MtpDeviceInfo* info = new MtpDeviceInfo;
    351         if (info->read(mData))
    352             return info;
    353         else
    354             delete info;
    355     }
    356     return NULL;
    357 }
    358 
    359 MtpStorageIDList* MtpDevice::getStorageIDs() {
    360     Mutex::Autolock autoLock(mMutex);
    361 
    362     mRequest.reset();
    363     if (!sendRequest(MTP_OPERATION_GET_STORAGE_IDS))
    364         return NULL;
    365     if (!readData())
    366         return NULL;
    367     MtpResponseCode ret = readResponse();
    368     if (ret == MTP_RESPONSE_OK) {
    369         return mData.getAUInt32();
    370     }
    371     return NULL;
    372 }
    373 
    374 MtpStorageInfo* MtpDevice::getStorageInfo(MtpStorageID storageID) {
    375     Mutex::Autolock autoLock(mMutex);
    376 
    377     mRequest.reset();
    378     mRequest.setParameter(1, storageID);
    379     if (!sendRequest(MTP_OPERATION_GET_STORAGE_INFO))
    380         return NULL;
    381     if (!readData())
    382         return NULL;
    383     MtpResponseCode ret = readResponse();
    384     if (ret == MTP_RESPONSE_OK) {
    385         MtpStorageInfo* info = new MtpStorageInfo(storageID);
    386         if (info->read(mData))
    387             return info;
    388         else
    389             delete info;
    390     }
    391     return NULL;
    392 }
    393 
    394 MtpObjectHandleList* MtpDevice::getObjectHandles(MtpStorageID storageID,
    395             MtpObjectFormat format, MtpObjectHandle parent) {
    396     Mutex::Autolock autoLock(mMutex);
    397 
    398     mRequest.reset();
    399     mRequest.setParameter(1, storageID);
    400     mRequest.setParameter(2, format);
    401     mRequest.setParameter(3, parent);
    402     if (!sendRequest(MTP_OPERATION_GET_OBJECT_HANDLES))
    403         return NULL;
    404     if (!readData())
    405         return NULL;
    406     MtpResponseCode ret = readResponse();
    407     if (ret == MTP_RESPONSE_OK) {
    408         return mData.getAUInt32();
    409     }
    410     return NULL;
    411 }
    412 
    413 MtpObjectInfo* MtpDevice::getObjectInfo(MtpObjectHandle handle) {
    414     Mutex::Autolock autoLock(mMutex);
    415 
    416     // FIXME - we might want to add some caching here
    417 
    418     mRequest.reset();
    419     mRequest.setParameter(1, handle);
    420     if (!sendRequest(MTP_OPERATION_GET_OBJECT_INFO))
    421         return NULL;
    422     if (!readData())
    423         return NULL;
    424     MtpResponseCode ret = readResponse();
    425     if (ret == MTP_RESPONSE_OK) {
    426         MtpObjectInfo* info = new MtpObjectInfo(handle);
    427         if (info->read(mData))
    428             return info;
    429         else
    430             delete info;
    431     }
    432     return NULL;
    433 }
    434 
    435 void* MtpDevice::getThumbnail(MtpObjectHandle handle, int& outLength) {
    436     Mutex::Autolock autoLock(mMutex);
    437 
    438     mRequest.reset();
    439     mRequest.setParameter(1, handle);
    440     if (sendRequest(MTP_OPERATION_GET_THUMB) && readData()) {
    441         MtpResponseCode ret = readResponse();
    442         if (ret == MTP_RESPONSE_OK) {
    443             return mData.getData(&outLength);
    444         }
    445     }
    446     outLength = 0;
    447     return NULL;
    448 }
    449 
    450 MtpObjectHandle MtpDevice::sendObjectInfo(MtpObjectInfo* info) {
    451     Mutex::Autolock autoLock(mMutex);
    452 
    453     mRequest.reset();
    454     MtpObjectHandle parent = info->mParent;
    455     if (parent == 0)
    456         parent = MTP_PARENT_ROOT;
    457 
    458     mRequest.setParameter(1, info->mStorageID);
    459     mRequest.setParameter(2, parent);
    460 
    461     mData.reset();
    462     mData.putUInt32(info->mStorageID);
    463     mData.putUInt16(info->mFormat);
    464     mData.putUInt16(info->mProtectionStatus);
    465     mData.putUInt32(info->mCompressedSize);
    466     mData.putUInt16(info->mThumbFormat);
    467     mData.putUInt32(info->mThumbCompressedSize);
    468     mData.putUInt32(info->mThumbPixWidth);
    469     mData.putUInt32(info->mThumbPixHeight);
    470     mData.putUInt32(info->mImagePixWidth);
    471     mData.putUInt32(info->mImagePixHeight);
    472     mData.putUInt32(info->mImagePixDepth);
    473     mData.putUInt32(info->mParent);
    474     mData.putUInt16(info->mAssociationType);
    475     mData.putUInt32(info->mAssociationDesc);
    476     mData.putUInt32(info->mSequenceNumber);
    477     mData.putString(info->mName);
    478 
    479     char created[100], modified[100];
    480     formatDateTime(info->mDateCreated, created, sizeof(created));
    481     formatDateTime(info->mDateModified, modified, sizeof(modified));
    482 
    483     mData.putString(created);
    484     mData.putString(modified);
    485     if (info->mKeywords)
    486         mData.putString(info->mKeywords);
    487     else
    488         mData.putEmptyString();
    489 
    490    if (sendRequest(MTP_OPERATION_SEND_OBJECT_INFO) && sendData()) {
    491         MtpResponseCode ret = readResponse();
    492         if (ret == MTP_RESPONSE_OK) {
    493             info->mStorageID = mResponse.getParameter(1);
    494             info->mParent = mResponse.getParameter(2);
    495             info->mHandle = mResponse.getParameter(3);
    496             return info->mHandle;
    497         }
    498     }
    499     return (MtpObjectHandle)-1;
    500 }
    501 
    502 bool MtpDevice::sendObject(MtpObjectHandle handle, int size, int srcFD) {
    503     Mutex::Autolock autoLock(mMutex);
    504 
    505     int remaining = size;
    506     mRequest.reset();
    507     mRequest.setParameter(1, handle);
    508     bool error = false;
    509     if (sendRequest(MTP_OPERATION_SEND_OBJECT)) {
    510         // send data header
    511         writeDataHeader(MTP_OPERATION_SEND_OBJECT, remaining);
    512 
    513         // USB writes greater than 16K don't work
    514         char buffer[MTP_BUFFER_SIZE];
    515         while (remaining > 0) {
    516             int count = read(srcFD, buffer, sizeof(buffer));
    517             if (count > 0) {
    518                 if (mData.write(mRequestOut, buffer, count) < 0) {
    519                     error = true;
    520                 }
    521                 // FIXME check error
    522                 remaining -= count;
    523             } else {
    524                 break;
    525             }
    526         }
    527     }
    528     MtpResponseCode ret = readResponse();
    529     return (remaining == 0 && ret == MTP_RESPONSE_OK && !error);
    530 }
    531 
    532 bool MtpDevice::deleteObject(MtpObjectHandle handle) {
    533     Mutex::Autolock autoLock(mMutex);
    534 
    535     mRequest.reset();
    536     mRequest.setParameter(1, handle);
    537     if (sendRequest(MTP_OPERATION_DELETE_OBJECT)) {
    538         MtpResponseCode ret = readResponse();
    539         if (ret == MTP_RESPONSE_OK)
    540             return true;
    541     }
    542     return false;
    543 }
    544 
    545 MtpObjectHandle MtpDevice::getParent(MtpObjectHandle handle) {
    546     MtpObjectInfo* info = getObjectInfo(handle);
    547     if (info) {
    548         MtpObjectHandle parent = info->mParent;
    549         delete info;
    550         return parent;
    551     } else {
    552         return -1;
    553     }
    554 }
    555 
    556 MtpObjectHandle MtpDevice::getStorageID(MtpObjectHandle handle) {
    557     MtpObjectInfo* info = getObjectInfo(handle);
    558     if (info) {
    559         MtpObjectHandle storageId = info->mStorageID;
    560         delete info;
    561         return storageId;
    562     } else {
    563         return -1;
    564     }
    565 }
    566 
    567 MtpObjectPropertyList* MtpDevice::getObjectPropsSupported(MtpObjectFormat format) {
    568     Mutex::Autolock autoLock(mMutex);
    569 
    570     mRequest.reset();
    571     mRequest.setParameter(1, format);
    572     if (!sendRequest(MTP_OPERATION_GET_OBJECT_PROPS_SUPPORTED))
    573         return NULL;
    574     if (!readData())
    575         return NULL;
    576     MtpResponseCode ret = readResponse();
    577     if (ret == MTP_RESPONSE_OK) {
    578         return mData.getAUInt16();
    579     }
    580     return NULL;
    581 
    582 }
    583 
    584 MtpProperty* MtpDevice::getDevicePropDesc(MtpDeviceProperty code) {
    585     Mutex::Autolock autoLock(mMutex);
    586 
    587     mRequest.reset();
    588     mRequest.setParameter(1, code);
    589     if (!sendRequest(MTP_OPERATION_GET_DEVICE_PROP_DESC))
    590         return NULL;
    591     if (!readData())
    592         return NULL;
    593     MtpResponseCode ret = readResponse();
    594     if (ret == MTP_RESPONSE_OK) {
    595         MtpProperty* property = new MtpProperty;
    596         if (property->read(mData))
    597             return property;
    598         else
    599             delete property;
    600     }
    601     return NULL;
    602 }
    603 
    604 MtpProperty* MtpDevice::getObjectPropDesc(MtpObjectProperty code, MtpObjectFormat format) {
    605     Mutex::Autolock autoLock(mMutex);
    606 
    607     mRequest.reset();
    608     mRequest.setParameter(1, code);
    609     mRequest.setParameter(2, format);
    610     if (!sendRequest(MTP_OPERATION_GET_OBJECT_PROP_DESC))
    611         return NULL;
    612     if (!readData())
    613         return NULL;
    614     const MtpResponseCode ret = readResponse();
    615     if (ret == MTP_RESPONSE_OK) {
    616         MtpProperty* property = new MtpProperty;
    617         if (property->read(mData))
    618             return property;
    619         else
    620             delete property;
    621     }
    622     return NULL;
    623 }
    624 
    625 bool MtpDevice::getObjectPropValue(MtpObjectHandle handle, MtpProperty* property) {
    626     if (property == nullptr)
    627         return false;
    628 
    629     Mutex::Autolock autoLock(mMutex);
    630 
    631     mRequest.reset();
    632     mRequest.setParameter(1, handle);
    633     mRequest.setParameter(2, property->getPropertyCode());
    634     if (!sendRequest(MTP_OPERATION_GET_OBJECT_PROP_VALUE))
    635         return false;
    636     if (!readData())
    637         return false;
    638     if (readResponse() != MTP_RESPONSE_OK)
    639         return false;
    640     property->setCurrentValue(mData);
    641     return true;
    642 }
    643 
    644 bool MtpDevice::readObject(MtpObjectHandle handle,
    645                            ReadObjectCallback callback,
    646                            uint32_t expectedLength,
    647                            void* clientData) {
    648     return readObjectInternal(handle, callback, &expectedLength, clientData);
    649 }
    650 
    651 // reads the object's data and writes it to the specified file path
    652 bool MtpDevice::readObject(MtpObjectHandle handle, const char* destPath, int group, int perm) {
    653     ALOGD("readObject: %s", destPath);
    654     int fd = ::open(destPath, O_RDWR | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR);
    655     if (fd < 0) {
    656         ALOGE("open failed for %s", destPath);
    657         return false;
    658     }
    659 
    660     fchown(fd, getuid(), group);
    661     // set permissions
    662     int mask = umask(0);
    663     fchmod(fd, perm);
    664     umask(mask);
    665 
    666     bool result = readObject(handle, fd);
    667     ::close(fd);
    668     return result;
    669 }
    670 
    671 bool MtpDevice::readObject(MtpObjectHandle handle, int fd) {
    672     ALOGD("readObject: %d", fd);
    673     return readObjectInternal(handle, writeToFd, NULL /* expected size */, &fd);
    674 }
    675 
    676 bool MtpDevice::readObjectInternal(MtpObjectHandle handle,
    677                                    ReadObjectCallback callback,
    678                                    const uint32_t* expectedLength,
    679                                    void* clientData) {
    680     Mutex::Autolock autoLock(mMutex);
    681 
    682     mRequest.reset();
    683     mRequest.setParameter(1, handle);
    684     if (!sendRequest(MTP_OPERATION_GET_OBJECT)) {
    685         ALOGE("Failed to send a read request.");
    686         return false;
    687     }
    688 
    689     return readData(callback, expectedLength, nullptr, clientData);
    690 }
    691 
    692 bool MtpDevice::readData(ReadObjectCallback callback,
    693                             const uint32_t* expectedLength,
    694                             uint32_t* writtenSize,
    695                             void* clientData) {
    696     if (!mData.readDataHeader(mRequestIn1)) {
    697         ALOGE("Failed to read header.");
    698         return false;
    699     }
    700 
    701     // If object size 0 byte, the remote device can reply response packet
    702     // without sending any data packets.
    703     if (mData.getContainerType() == MTP_CONTAINER_TYPE_RESPONSE) {
    704         mResponse.copyFrom(mData);
    705         return mResponse.getResponseCode() == MTP_RESPONSE_OK;
    706     }
    707 
    708     const uint32_t fullLength = mData.getContainerLength();
    709     if (fullLength < MTP_CONTAINER_HEADER_SIZE) {
    710         ALOGE("fullLength is too short: %d", fullLength);
    711         return false;
    712     }
    713     const uint32_t length = fullLength - MTP_CONTAINER_HEADER_SIZE;
    714     if (expectedLength && length != *expectedLength) {
    715         ALOGE("readObject error length: %d", fullLength);
    716         return false;
    717     }
    718 
    719     uint32_t offset = 0;
    720     bool writingError = false;
    721 
    722     {
    723         int initialDataLength = 0;
    724         void* const initialData = mData.getData(&initialDataLength);
    725         if (initialData) {
    726             if (initialDataLength > 0) {
    727                 if (!callback(initialData, offset, initialDataLength, clientData)) {
    728                     ALOGE("Failed to write initial data.");
    729                     writingError = true;
    730                 }
    731                 offset += initialDataLength;
    732             }
    733             free(initialData);
    734         }
    735     }
    736 
    737     // USB reads greater than 16K don't work.
    738     char buffer1[MTP_BUFFER_SIZE], buffer2[MTP_BUFFER_SIZE];
    739     mRequestIn1->buffer = buffer1;
    740     mRequestIn2->buffer = buffer2;
    741     struct usb_request* req = NULL;
    742 
    743     while (offset < length) {
    744         // Wait for previous read to complete.
    745         void* writeBuffer = NULL;
    746         int writeLength = 0;
    747         if (req) {
    748             const int read = mData.readDataWait(mDevice);
    749             if (read < 0) {
    750                 ALOGE("readDataWait failed.");
    751                 return false;
    752             }
    753             writeBuffer = req->buffer;
    754             writeLength = read;
    755         }
    756 
    757         // Request to read next chunk.
    758         const uint32_t nextOffset = offset + writeLength;
    759         if (nextOffset < length) {
    760             // Queue up a read request.
    761             const size_t remaining = length - nextOffset;
    762             req = (req == mRequestIn1 ? mRequestIn2 : mRequestIn1);
    763             req->buffer_length = remaining > MTP_BUFFER_SIZE ?
    764                     static_cast<size_t>(MTP_BUFFER_SIZE) : remaining;
    765             if (mData.readDataAsync(req) != 0) {
    766                 ALOGE("readDataAsync failed");
    767                 return false;
    768             }
    769         }
    770 
    771         // Write previous buffer.
    772         if (writeBuffer && !writingError) {
    773             if (!callback(writeBuffer, offset, writeLength, clientData)) {
    774                 ALOGE("write failed");
    775                 writingError = true;
    776             }
    777         }
    778         offset = nextOffset;
    779     }
    780 
    781     if (writtenSize) {
    782         *writtenSize = length;
    783     }
    784 
    785     return readResponse() == MTP_RESPONSE_OK;
    786 }
    787 
    788 bool MtpDevice::readPartialObject(MtpObjectHandle handle,
    789                                   uint32_t offset,
    790                                   uint32_t size,
    791                                   uint32_t *writtenSize,
    792                                   ReadObjectCallback callback,
    793                                   void* clientData) {
    794     Mutex::Autolock autoLock(mMutex);
    795 
    796     mRequest.reset();
    797     mRequest.setParameter(1, handle);
    798     mRequest.setParameter(2, offset);
    799     mRequest.setParameter(3, size);
    800     if (!sendRequest(MTP_OPERATION_GET_PARTIAL_OBJECT)) {
    801         ALOGE("Failed to send a read request.");
    802         return false;
    803     }
    804     // The expected size is null because it requires the exact number of bytes to read though
    805     // MTP_OPERATION_GET_PARTIAL_OBJECT allows devices to return shorter length of bytes than
    806     // requested. Destination's buffer length should be checked in |callback|.
    807     return readData(callback, nullptr /* expected size */, writtenSize, clientData);
    808 }
    809 
    810 bool MtpDevice::readPartialObject64(MtpObjectHandle handle,
    811                                     uint64_t offset,
    812                                     uint32_t size,
    813                                     uint32_t *writtenSize,
    814                                     ReadObjectCallback callback,
    815                                     void* clientData) {
    816     Mutex::Autolock autoLock(mMutex);
    817 
    818     mRequest.reset();
    819     mRequest.setParameter(1, handle);
    820     mRequest.setParameter(2, 0xffffffff & offset);
    821     mRequest.setParameter(3, 0xffffffff & (offset >> 32));
    822     mRequest.setParameter(4, size);
    823     if (!sendRequest(MTP_OPERATION_GET_PARTIAL_OBJECT_64)) {
    824         ALOGE("Failed to send a read request.");
    825         return false;
    826     }
    827     // The expected size is null because it requires the exact number of bytes to read though
    828     // MTP_OPERATION_GET_PARTIAL_OBJECT_64 allows devices to return shorter length of bytes than
    829     // requested. Destination's buffer length should be checked in |callback|.
    830     return readData(callback, nullptr /* expected size */, writtenSize, clientData);
    831 }
    832 
    833 bool MtpDevice::sendRequest(MtpOperationCode operation) {
    834     ALOGV("sendRequest: %s\n", MtpDebug::getOperationCodeName(operation));
    835     mReceivedResponse = false;
    836     mRequest.setOperationCode(operation);
    837     if (mTransactionID > 0)
    838         mRequest.setTransactionID(mTransactionID++);
    839     int ret = mRequest.write(mRequestOut);
    840     mRequest.dump();
    841     return (ret > 0);
    842 }
    843 
    844 bool MtpDevice::sendData() {
    845     ALOGV("sendData\n");
    846     mData.setOperationCode(mRequest.getOperationCode());
    847     mData.setTransactionID(mRequest.getTransactionID());
    848     int ret = mData.write(mRequestOut);
    849     mData.dump();
    850     return (ret >= 0);
    851 }
    852 
    853 bool MtpDevice::readData() {
    854     mData.reset();
    855     int ret = mData.read(mRequestIn1);
    856     ALOGV("readData returned %d\n", ret);
    857     if (ret >= MTP_CONTAINER_HEADER_SIZE) {
    858         if (mData.getContainerType() == MTP_CONTAINER_TYPE_RESPONSE) {
    859             ALOGD("got response packet instead of data packet");
    860             // we got a response packet rather than data
    861             // copy it to mResponse
    862             mResponse.copyFrom(mData);
    863             mReceivedResponse = true;
    864             return false;
    865         }
    866         mData.dump();
    867         return true;
    868     }
    869     else {
    870         ALOGV("readResponse failed\n");
    871         return false;
    872     }
    873 }
    874 
    875 bool MtpDevice::writeDataHeader(MtpOperationCode operation, int dataLength) {
    876     mData.setOperationCode(operation);
    877     mData.setTransactionID(mRequest.getTransactionID());
    878     return (!mData.writeDataHeader(mRequestOut, dataLength));
    879 }
    880 
    881 MtpResponseCode MtpDevice::readResponse() {
    882     ALOGV("readResponse\n");
    883     if (mReceivedResponse) {
    884         mReceivedResponse = false;
    885         return mResponse.getResponseCode();
    886     }
    887     int ret = mResponse.read(mRequestIn1);
    888     // handle zero length packets, which might occur if the data transfer
    889     // ends on a packet boundary
    890     if (ret == 0)
    891         ret = mResponse.read(mRequestIn1);
    892     if (ret >= MTP_CONTAINER_HEADER_SIZE) {
    893         mResponse.dump();
    894         return mResponse.getResponseCode();
    895     } else {
    896         ALOGD("readResponse failed\n");
    897         return -1;
    898     }
    899 }
    900 
    901 int MtpDevice::submitEventRequest() {
    902     if (mEventMutex.tryLock()) {
    903         // An event is being reaped on another thread.
    904         return -1;
    905     }
    906     if (mProcessingEvent) {
    907         // An event request was submitted, but no reapEventRequest called so far.
    908         return -1;
    909     }
    910     Mutex::Autolock autoLock(mEventMutexForInterrupt);
    911     mEventPacket.sendRequest(mRequestIntr);
    912     const int currentHandle = ++mCurrentEventHandle;
    913     mProcessingEvent = true;
    914     mEventMutex.unlock();
    915     return currentHandle;
    916 }
    917 
    918 int MtpDevice::reapEventRequest(int handle, uint32_t (*parameters)[3]) {
    919     Mutex::Autolock autoLock(mEventMutex);
    920     if (!mProcessingEvent || mCurrentEventHandle != handle || !parameters) {
    921         return -1;
    922     }
    923     mProcessingEvent = false;
    924     const int readSize = mEventPacket.readResponse(mRequestIntr->dev);
    925     const int result = mEventPacket.getEventCode();
    926     // MTP event has three parameters.
    927     (*parameters)[0] = mEventPacket.getParameter(1);
    928     (*parameters)[1] = mEventPacket.getParameter(2);
    929     (*parameters)[2] = mEventPacket.getParameter(3);
    930     return readSize != 0 ? result : 0;
    931 }
    932 
    933 void MtpDevice::discardEventRequest(int handle) {
    934     Mutex::Autolock autoLock(mEventMutexForInterrupt);
    935     if (mCurrentEventHandle != handle) {
    936         return;
    937     }
    938     usb_request_cancel(mRequestIntr);
    939 }
    940 
    941 }  // namespace android
    942