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 "MtpObjectInfo.h"
23#include "MtpProperty.h"
24#include "MtpStorageInfo.h"
25#include "MtpStringBuffer.h"
26#include "MtpUtils.h"
27
28#include <stdio.h>
29#include <stdlib.h>
30#include <sys/types.h>
31#include <sys/ioctl.h>
32#include <sys/stat.h>
33#include <fcntl.h>
34#include <errno.h>
35#include <endian.h>
36
37#include <usbhost/usbhost.h>
38
39namespace android {
40
41#if 0
42static bool isMtpDevice(uint16_t vendor, uint16_t product) {
43    // Sandisk Sansa Fuze
44    if (vendor == 0x0781 && product == 0x74c2)
45        return true;
46    // Samsung YP-Z5
47    if (vendor == 0x04e8 && product == 0x503c)
48        return true;
49    return false;
50}
51#endif
52
53MtpDevice* MtpDevice::open(const char* deviceName, int fd) {
54    struct usb_device *device = usb_device_new(deviceName, fd);
55    if (!device) {
56        ALOGE("usb_device_new failed for %s", deviceName);
57        return NULL;
58    }
59
60    struct usb_descriptor_header* desc;
61    struct usb_descriptor_iter iter;
62
63    usb_descriptor_iter_init(device, &iter);
64
65    while ((desc = usb_descriptor_iter_next(&iter)) != NULL) {
66        if (desc->bDescriptorType == USB_DT_INTERFACE) {
67            struct usb_interface_descriptor *interface = (struct usb_interface_descriptor *)desc;
68
69            if (interface->bInterfaceClass == USB_CLASS_STILL_IMAGE &&
70                interface->bInterfaceSubClass == 1 && // Still Image Capture
71                interface->bInterfaceProtocol == 1)     // Picture Transfer Protocol (PIMA 15470)
72            {
73                char* manufacturerName = usb_device_get_manufacturer_name(device);
74                char* productName = usb_device_get_product_name(device);
75                ALOGD("Found camera: \"%s\" \"%s\"\n", manufacturerName, productName);
76                free(manufacturerName);
77                free(productName);
78            } else if (interface->bInterfaceClass == 0xFF &&
79                    interface->bInterfaceSubClass == 0xFF &&
80                    interface->bInterfaceProtocol == 0) {
81                char* interfaceName = usb_device_get_string(device, interface->iInterface);
82                if (!interfaceName) {
83                    continue;
84                } else if (strcmp(interfaceName, "MTP")) {
85                    free(interfaceName);
86                    continue;
87                }
88                free(interfaceName);
89
90                // Looks like an android style MTP device
91                char* manufacturerName = usb_device_get_manufacturer_name(device);
92                char* productName = usb_device_get_product_name(device);
93                ALOGD("Found MTP device: \"%s\" \"%s\"\n", manufacturerName, productName);
94                free(manufacturerName);
95                free(productName);
96            }
97#if 0
98             else {
99                // look for special cased devices based on vendor/product ID
100                // we are doing this mainly for testing purposes
101                uint16_t vendor = usb_device_get_vendor_id(device);
102                uint16_t product = usb_device_get_product_id(device);
103                if (!isMtpDevice(vendor, product)) {
104                    // not an MTP or PTP device
105                    continue;
106                }
107                // request MTP OS string and descriptor
108                // some music players need to see this before entering MTP mode.
109                char buffer[256];
110                memset(buffer, 0, sizeof(buffer));
111                int ret = usb_device_control_transfer(device,
112                        USB_DIR_IN|USB_RECIP_DEVICE|USB_TYPE_STANDARD,
113                        USB_REQ_GET_DESCRIPTOR, (USB_DT_STRING << 8) | 0xEE,
114                        0, buffer, sizeof(buffer), 0);
115                printf("usb_device_control_transfer returned %d errno: %d\n", ret, errno);
116                if (ret > 0) {
117                    printf("got MTP string %s\n", buffer);
118                    ret = usb_device_control_transfer(device,
119                            USB_DIR_IN|USB_RECIP_DEVICE|USB_TYPE_VENDOR, 1,
120                            0, 4, buffer, sizeof(buffer), 0);
121                    printf("OS descriptor got %d\n", ret);
122                } else {
123                    printf("no MTP string\n");
124                }
125            }
126#endif
127            // if we got here, then we have a likely MTP or PTP device
128
129            // interface should be followed by three endpoints
130            struct usb_endpoint_descriptor *ep;
131            struct usb_endpoint_descriptor *ep_in_desc = NULL;
132            struct usb_endpoint_descriptor *ep_out_desc = NULL;
133            struct usb_endpoint_descriptor *ep_intr_desc = NULL;
134            for (int i = 0; i < 3; i++) {
135                ep = (struct usb_endpoint_descriptor *)usb_descriptor_iter_next(&iter);
136                if (!ep || ep->bDescriptorType != USB_DT_ENDPOINT) {
137                    ALOGE("endpoints not found\n");
138                    usb_device_close(device);
139                    return NULL;
140                }
141                if (ep->bmAttributes == USB_ENDPOINT_XFER_BULK) {
142                    if (ep->bEndpointAddress & USB_ENDPOINT_DIR_MASK)
143                        ep_in_desc = ep;
144                    else
145                        ep_out_desc = ep;
146                } else if (ep->bmAttributes == USB_ENDPOINT_XFER_INT &&
147                    ep->bEndpointAddress & USB_ENDPOINT_DIR_MASK) {
148                    ep_intr_desc = ep;
149                }
150            }
151            if (!ep_in_desc || !ep_out_desc || !ep_intr_desc) {
152                ALOGE("endpoints not found\n");
153                usb_device_close(device);
154                return NULL;
155            }
156
157            if (usb_device_claim_interface(device, interface->bInterfaceNumber)) {
158                ALOGE("usb_device_claim_interface failed errno: %d\n", errno);
159                usb_device_close(device);
160                return NULL;
161            }
162
163            MtpDevice* mtpDevice = new MtpDevice(device, interface->bInterfaceNumber,
164                        ep_in_desc, ep_out_desc, ep_intr_desc);
165            mtpDevice->initialize();
166            return mtpDevice;
167        }
168    }
169
170    usb_device_close(device);
171    ALOGE("device not found");
172    return NULL;
173}
174
175MtpDevice::MtpDevice(struct usb_device* device, int interface,
176            const struct usb_endpoint_descriptor *ep_in,
177            const struct usb_endpoint_descriptor *ep_out,
178            const struct usb_endpoint_descriptor *ep_intr)
179    :   mDevice(device),
180        mInterface(interface),
181        mRequestIn1(NULL),
182        mRequestIn2(NULL),
183        mRequestOut(NULL),
184        mRequestIntr(NULL),
185        mDeviceInfo(NULL),
186        mSessionID(0),
187        mTransactionID(0),
188        mReceivedResponse(false)
189{
190    mRequestIn1 = usb_request_new(device, ep_in);
191    mRequestIn2 = usb_request_new(device, ep_in);
192    mRequestOut = usb_request_new(device, ep_out);
193    mRequestIntr = usb_request_new(device, ep_intr);
194}
195
196MtpDevice::~MtpDevice() {
197    close();
198    for (size_t i = 0; i < mDeviceProperties.size(); i++)
199        delete mDeviceProperties[i];
200    usb_request_free(mRequestIn1);
201    usb_request_free(mRequestIn2);
202    usb_request_free(mRequestOut);
203    usb_request_free(mRequestIntr);
204}
205
206void MtpDevice::initialize() {
207    openSession();
208    mDeviceInfo = getDeviceInfo();
209    if (mDeviceInfo) {
210        if (mDeviceInfo->mDeviceProperties) {
211            int count = mDeviceInfo->mDeviceProperties->size();
212            for (int i = 0; i < count; i++) {
213                MtpDeviceProperty propCode = (*mDeviceInfo->mDeviceProperties)[i];
214                MtpProperty* property = getDevicePropDesc(propCode);
215                if (property)
216                    mDeviceProperties.push(property);
217            }
218        }
219    }
220}
221
222void MtpDevice::close() {
223    if (mDevice) {
224        usb_device_release_interface(mDevice, mInterface);
225        usb_device_close(mDevice);
226        mDevice = NULL;
227    }
228}
229
230void MtpDevice::print() {
231    if (mDeviceInfo) {
232        mDeviceInfo->print();
233
234        if (mDeviceInfo->mDeviceProperties) {
235            ALOGI("***** DEVICE PROPERTIES *****\n");
236            int count = mDeviceInfo->mDeviceProperties->size();
237            for (int i = 0; i < count; i++) {
238                MtpDeviceProperty propCode = (*mDeviceInfo->mDeviceProperties)[i];
239                MtpProperty* property = getDevicePropDesc(propCode);
240                if (property) {
241                    property->print();
242                    delete property;
243                }
244            }
245        }
246    }
247
248    if (mDeviceInfo->mPlaybackFormats) {
249            ALOGI("***** OBJECT PROPERTIES *****\n");
250        int count = mDeviceInfo->mPlaybackFormats->size();
251        for (int i = 0; i < count; i++) {
252            MtpObjectFormat format = (*mDeviceInfo->mPlaybackFormats)[i];
253            ALOGI("*** FORMAT: %s\n", MtpDebug::getFormatCodeName(format));
254            MtpObjectPropertyList* props = getObjectPropsSupported(format);
255            if (props) {
256                for (size_t j = 0; j < props->size(); j++) {
257                    MtpObjectProperty prop = (*props)[j];
258                    MtpProperty* property = getObjectPropDesc(prop, format);
259                    if (property) {
260                        property->print();
261                        delete property;
262                    } else {
263                        ALOGE("could not fetch property: %s",
264                                MtpDebug::getObjectPropCodeName(prop));
265                    }
266                }
267            }
268        }
269    }
270}
271
272const char* MtpDevice::getDeviceName() {
273    if (mDevice)
274        return usb_device_get_name(mDevice);
275    else
276        return "???";
277}
278
279bool MtpDevice::openSession() {
280    Mutex::Autolock autoLock(mMutex);
281
282    mSessionID = 0;
283    mTransactionID = 0;
284    MtpSessionID newSession = 1;
285    mRequest.reset();
286    mRequest.setParameter(1, newSession);
287    if (!sendRequest(MTP_OPERATION_OPEN_SESSION))
288        return false;
289    MtpResponseCode ret = readResponse();
290    if (ret == MTP_RESPONSE_SESSION_ALREADY_OPEN)
291        newSession = mResponse.getParameter(1);
292    else if (ret != MTP_RESPONSE_OK)
293        return false;
294
295    mSessionID = newSession;
296    mTransactionID = 1;
297    return true;
298}
299
300bool MtpDevice::closeSession() {
301    // FIXME
302    return true;
303}
304
305MtpDeviceInfo* MtpDevice::getDeviceInfo() {
306    Mutex::Autolock autoLock(mMutex);
307
308    mRequest.reset();
309    if (!sendRequest(MTP_OPERATION_GET_DEVICE_INFO))
310        return NULL;
311    if (!readData())
312        return NULL;
313    MtpResponseCode ret = readResponse();
314    if (ret == MTP_RESPONSE_OK) {
315        MtpDeviceInfo* info = new MtpDeviceInfo;
316        if (info->read(mData))
317            return info;
318        else
319            delete info;
320    }
321    return NULL;
322}
323
324MtpStorageIDList* MtpDevice::getStorageIDs() {
325    Mutex::Autolock autoLock(mMutex);
326
327    mRequest.reset();
328    if (!sendRequest(MTP_OPERATION_GET_STORAGE_IDS))
329        return NULL;
330    if (!readData())
331        return NULL;
332    MtpResponseCode ret = readResponse();
333    if (ret == MTP_RESPONSE_OK) {
334        return mData.getAUInt32();
335    }
336    return NULL;
337}
338
339MtpStorageInfo* MtpDevice::getStorageInfo(MtpStorageID storageID) {
340    Mutex::Autolock autoLock(mMutex);
341
342    mRequest.reset();
343    mRequest.setParameter(1, storageID);
344    if (!sendRequest(MTP_OPERATION_GET_STORAGE_INFO))
345        return NULL;
346    if (!readData())
347        return NULL;
348    MtpResponseCode ret = readResponse();
349    if (ret == MTP_RESPONSE_OK) {
350        MtpStorageInfo* info = new MtpStorageInfo(storageID);
351        if (info->read(mData))
352            return info;
353        else
354            delete info;
355    }
356    return NULL;
357}
358
359MtpObjectHandleList* MtpDevice::getObjectHandles(MtpStorageID storageID,
360            MtpObjectFormat format, MtpObjectHandle parent) {
361    Mutex::Autolock autoLock(mMutex);
362
363    mRequest.reset();
364    mRequest.setParameter(1, storageID);
365    mRequest.setParameter(2, format);
366    mRequest.setParameter(3, parent);
367    if (!sendRequest(MTP_OPERATION_GET_OBJECT_HANDLES))
368        return NULL;
369    if (!readData())
370        return NULL;
371    MtpResponseCode ret = readResponse();
372    if (ret == MTP_RESPONSE_OK) {
373        return mData.getAUInt32();
374    }
375    return NULL;
376}
377
378MtpObjectInfo* MtpDevice::getObjectInfo(MtpObjectHandle handle) {
379    Mutex::Autolock autoLock(mMutex);
380
381    // FIXME - we might want to add some caching here
382
383    mRequest.reset();
384    mRequest.setParameter(1, handle);
385    if (!sendRequest(MTP_OPERATION_GET_OBJECT_INFO))
386        return NULL;
387    if (!readData())
388        return NULL;
389    MtpResponseCode ret = readResponse();
390    if (ret == MTP_RESPONSE_OK) {
391        MtpObjectInfo* info = new MtpObjectInfo(handle);
392        if (info->read(mData))
393            return info;
394        else
395            delete info;
396    }
397    return NULL;
398}
399
400void* MtpDevice::getThumbnail(MtpObjectHandle handle, int& outLength) {
401    Mutex::Autolock autoLock(mMutex);
402
403    mRequest.reset();
404    mRequest.setParameter(1, handle);
405    if (sendRequest(MTP_OPERATION_GET_THUMB) && readData()) {
406        MtpResponseCode ret = readResponse();
407        if (ret == MTP_RESPONSE_OK) {
408            return mData.getData(outLength);
409        }
410    }
411    outLength = 0;
412    return NULL;
413}
414
415MtpObjectHandle MtpDevice::sendObjectInfo(MtpObjectInfo* info) {
416    Mutex::Autolock autoLock(mMutex);
417
418    mRequest.reset();
419    MtpObjectHandle parent = info->mParent;
420    if (parent == 0)
421        parent = MTP_PARENT_ROOT;
422
423    mRequest.setParameter(1, info->mStorageID);
424    mRequest.setParameter(2, info->mParent);
425
426    mData.putUInt32(info->mStorageID);
427    mData.putUInt16(info->mFormat);
428    mData.putUInt16(info->mProtectionStatus);
429    mData.putUInt32(info->mCompressedSize);
430    mData.putUInt16(info->mThumbFormat);
431    mData.putUInt32(info->mThumbCompressedSize);
432    mData.putUInt32(info->mThumbPixWidth);
433    mData.putUInt32(info->mThumbPixHeight);
434    mData.putUInt32(info->mImagePixWidth);
435    mData.putUInt32(info->mImagePixHeight);
436    mData.putUInt32(info->mImagePixDepth);
437    mData.putUInt32(info->mParent);
438    mData.putUInt16(info->mAssociationType);
439    mData.putUInt32(info->mAssociationDesc);
440    mData.putUInt32(info->mSequenceNumber);
441    mData.putString(info->mName);
442
443    char created[100], modified[100];
444    formatDateTime(info->mDateCreated, created, sizeof(created));
445    formatDateTime(info->mDateModified, modified, sizeof(modified));
446
447    mData.putString(created);
448    mData.putString(modified);
449    if (info->mKeywords)
450        mData.putString(info->mKeywords);
451    else
452        mData.putEmptyString();
453
454   if (sendRequest(MTP_OPERATION_SEND_OBJECT_INFO) && sendData()) {
455        MtpResponseCode ret = readResponse();
456        if (ret == MTP_RESPONSE_OK) {
457            info->mStorageID = mResponse.getParameter(1);
458            info->mParent = mResponse.getParameter(2);
459            info->mHandle = mResponse.getParameter(3);
460            return info->mHandle;
461        }
462    }
463    return (MtpObjectHandle)-1;
464}
465
466bool MtpDevice::sendObject(MtpObjectInfo* info, int srcFD) {
467    Mutex::Autolock autoLock(mMutex);
468
469    int remaining = info->mCompressedSize;
470    mRequest.reset();
471    mRequest.setParameter(1, info->mHandle);
472    if (sendRequest(MTP_OPERATION_SEND_OBJECT)) {
473        // send data header
474        writeDataHeader(MTP_OPERATION_SEND_OBJECT, remaining);
475
476        char buffer[65536];
477        while (remaining > 0) {
478            int count = read(srcFD, buffer, sizeof(buffer));
479            if (count > 0) {
480                int written = mData.write(mRequestOut, buffer, count);
481                // FIXME check error
482                remaining -= count;
483            } else {
484                break;
485            }
486        }
487    }
488    MtpResponseCode ret = readResponse();
489    return (remaining == 0 && ret == MTP_RESPONSE_OK);
490}
491
492bool MtpDevice::deleteObject(MtpObjectHandle handle) {
493    Mutex::Autolock autoLock(mMutex);
494
495    mRequest.reset();
496    mRequest.setParameter(1, handle);
497    if (sendRequest(MTP_OPERATION_DELETE_OBJECT)) {
498        MtpResponseCode ret = readResponse();
499        if (ret == MTP_RESPONSE_OK)
500            return true;
501    }
502    return false;
503}
504
505MtpObjectHandle MtpDevice::getParent(MtpObjectHandle handle) {
506    MtpObjectInfo* info = getObjectInfo(handle);
507    if (info) {
508        MtpObjectHandle parent = info->mParent;
509        delete info;
510        return parent;
511    } else {
512        return -1;
513    }
514}
515
516MtpObjectHandle MtpDevice::getStorageID(MtpObjectHandle handle) {
517    MtpObjectInfo* info = getObjectInfo(handle);
518    if (info) {
519        MtpObjectHandle storageId = info->mStorageID;
520        delete info;
521        return storageId;
522    } else {
523        return -1;
524    }
525}
526
527MtpObjectPropertyList* MtpDevice::getObjectPropsSupported(MtpObjectFormat format) {
528    Mutex::Autolock autoLock(mMutex);
529
530    mRequest.reset();
531    mRequest.setParameter(1, format);
532    if (!sendRequest(MTP_OPERATION_GET_OBJECT_PROPS_SUPPORTED))
533        return NULL;
534    if (!readData())
535        return NULL;
536    MtpResponseCode ret = readResponse();
537    if (ret == MTP_RESPONSE_OK) {
538        return mData.getAUInt16();
539    }
540    return NULL;
541
542}
543
544MtpProperty* MtpDevice::getDevicePropDesc(MtpDeviceProperty code) {
545    Mutex::Autolock autoLock(mMutex);
546
547    mRequest.reset();
548    mRequest.setParameter(1, code);
549    if (!sendRequest(MTP_OPERATION_GET_DEVICE_PROP_DESC))
550        return NULL;
551    if (!readData())
552        return NULL;
553    MtpResponseCode ret = readResponse();
554    if (ret == MTP_RESPONSE_OK) {
555        MtpProperty* property = new MtpProperty;
556        if (property->read(mData))
557            return property;
558        else
559            delete property;
560    }
561    return NULL;
562}
563
564MtpProperty* MtpDevice::getObjectPropDesc(MtpObjectProperty code, MtpObjectFormat format) {
565    Mutex::Autolock autoLock(mMutex);
566
567    mRequest.reset();
568    mRequest.setParameter(1, code);
569    mRequest.setParameter(2, format);
570    if (!sendRequest(MTP_OPERATION_GET_OBJECT_PROP_DESC))
571        return NULL;
572    if (!readData())
573        return NULL;
574    MtpResponseCode ret = readResponse();
575    if (ret == MTP_RESPONSE_OK) {
576        MtpProperty* property = new MtpProperty;
577        if (property->read(mData))
578            return property;
579        else
580            delete property;
581    }
582    return NULL;
583}
584
585bool MtpDevice::readObject(MtpObjectHandle handle,
586        bool (* callback)(void* data, int offset, int length, void* clientData),
587        size_t objectSize, void* clientData) {
588    Mutex::Autolock autoLock(mMutex);
589    bool result = false;
590
591    mRequest.reset();
592    mRequest.setParameter(1, handle);
593    if (sendRequest(MTP_OPERATION_GET_OBJECT)
594            && mData.readDataHeader(mRequestIn1)) {
595        uint32_t length = mData.getContainerLength();
596        if (length - MTP_CONTAINER_HEADER_SIZE != objectSize) {
597            ALOGE("readObject error objectSize: %d, length: %d",
598                    objectSize, length);
599            goto fail;
600        }
601        length -= MTP_CONTAINER_HEADER_SIZE;
602        uint32_t remaining = length;
603        int offset = 0;
604
605        int initialDataLength = 0;
606        void* initialData = mData.getData(initialDataLength);
607        if (initialData) {
608            if (initialDataLength > 0) {
609                if (!callback(initialData, 0, initialDataLength, clientData))
610                    goto fail;
611                remaining -= initialDataLength;
612                offset += initialDataLength;
613            }
614            free(initialData);
615        }
616
617        // USB reads greater than 16K don't work
618        char buffer1[16384], buffer2[16384];
619        mRequestIn1->buffer = buffer1;
620        mRequestIn2->buffer = buffer2;
621        struct usb_request* req = mRequestIn1;
622        void* writeBuffer = NULL;
623        int writeLength = 0;
624
625        while (remaining > 0 || writeBuffer) {
626            if (remaining > 0) {
627                // queue up a read request
628                req->buffer_length = (remaining > sizeof(buffer1) ? sizeof(buffer1) : remaining);
629                if (mData.readDataAsync(req)) {
630                    ALOGE("readDataAsync failed");
631                    goto fail;
632                }
633            } else {
634                req = NULL;
635            }
636
637            if (writeBuffer) {
638                // write previous buffer
639                if (!callback(writeBuffer, offset, writeLength, clientData)) {
640                    ALOGE("write failed");
641                    // wait for pending read before failing
642                    if (req)
643                        mData.readDataWait(mDevice);
644                    goto fail;
645                }
646                offset += writeLength;
647                writeBuffer = NULL;
648            }
649
650            // wait for read to complete
651            if (req) {
652                int read = mData.readDataWait(mDevice);
653                if (read < 0)
654                    goto fail;
655
656                if (read > 0) {
657                    writeBuffer = req->buffer;
658                    writeLength = read;
659                    remaining -= read;
660                    req = (req == mRequestIn1 ? mRequestIn2 : mRequestIn1);
661                } else {
662                    writeBuffer = NULL;
663                }
664            }
665        }
666
667        MtpResponseCode response = readResponse();
668        if (response == MTP_RESPONSE_OK)
669            result = true;
670    }
671
672fail:
673    return result;
674}
675
676
677// reads the object's data and writes it to the specified file path
678bool MtpDevice::readObject(MtpObjectHandle handle, const char* destPath, int group, int perm) {
679    ALOGD("readObject: %s", destPath);
680    int fd = ::open(destPath, O_RDWR | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR);
681    if (fd < 0) {
682        ALOGE("open failed for %s", destPath);
683        return false;
684    }
685
686    fchown(fd, getuid(), group);
687    // set permissions
688    int mask = umask(0);
689    fchmod(fd, perm);
690    umask(mask);
691
692    Mutex::Autolock autoLock(mMutex);
693    bool result = false;
694
695    mRequest.reset();
696    mRequest.setParameter(1, handle);
697    if (sendRequest(MTP_OPERATION_GET_OBJECT)
698            && mData.readDataHeader(mRequestIn1)) {
699        uint32_t length = mData.getContainerLength();
700        if (length < MTP_CONTAINER_HEADER_SIZE)
701            goto fail;
702        length -= MTP_CONTAINER_HEADER_SIZE;
703        uint32_t remaining = length;
704
705        int initialDataLength = 0;
706        void* initialData = mData.getData(initialDataLength);
707        if (initialData) {
708            if (initialDataLength > 0) {
709                if (write(fd, initialData, initialDataLength) != initialDataLength) {
710                    free(initialData);
711                    goto fail;
712                }
713                remaining -= initialDataLength;
714            }
715            free(initialData);
716        }
717
718        // USB reads greater than 16K don't work
719        char buffer1[16384], buffer2[16384];
720        mRequestIn1->buffer = buffer1;
721        mRequestIn2->buffer = buffer2;
722        struct usb_request* req = mRequestIn1;
723        void* writeBuffer = NULL;
724        int writeLength = 0;
725
726        while (remaining > 0 || writeBuffer) {
727            if (remaining > 0) {
728                // queue up a read request
729                req->buffer_length = (remaining > sizeof(buffer1) ? sizeof(buffer1) : remaining);
730                if (mData.readDataAsync(req)) {
731                    ALOGE("readDataAsync failed");
732                    goto fail;
733                }
734            } else {
735                req = NULL;
736            }
737
738            if (writeBuffer) {
739                // write previous buffer
740                if (write(fd, writeBuffer, writeLength) != writeLength) {
741                    ALOGE("write failed");
742                    // wait for pending read before failing
743                    if (req)
744                        mData.readDataWait(mDevice);
745                    goto fail;
746                }
747                writeBuffer = NULL;
748            }
749
750            // wait for read to complete
751            if (req) {
752                int read = mData.readDataWait(mDevice);
753                if (read < 0)
754                    goto fail;
755
756                if (read > 0) {
757                    writeBuffer = req->buffer;
758                    writeLength = read;
759                    remaining -= read;
760                    req = (req == mRequestIn1 ? mRequestIn2 : mRequestIn1);
761                } else {
762                    writeBuffer = NULL;
763                }
764            }
765        }
766
767        MtpResponseCode response = readResponse();
768        if (response == MTP_RESPONSE_OK)
769            result = true;
770    }
771
772fail:
773    ::close(fd);
774    return result;
775}
776
777bool MtpDevice::sendRequest(MtpOperationCode operation) {
778    ALOGV("sendRequest: %s\n", MtpDebug::getOperationCodeName(operation));
779    mReceivedResponse = false;
780    mRequest.setOperationCode(operation);
781    if (mTransactionID > 0)
782        mRequest.setTransactionID(mTransactionID++);
783    int ret = mRequest.write(mRequestOut);
784    mRequest.dump();
785    return (ret > 0);
786}
787
788bool MtpDevice::sendData() {
789    ALOGV("sendData\n");
790    mData.setOperationCode(mRequest.getOperationCode());
791    mData.setTransactionID(mRequest.getTransactionID());
792    int ret = mData.write(mRequestOut);
793    mData.dump();
794    return (ret > 0);
795}
796
797bool MtpDevice::readData() {
798    mData.reset();
799    int ret = mData.read(mRequestIn1);
800    ALOGV("readData returned %d\n", ret);
801    if (ret >= MTP_CONTAINER_HEADER_SIZE) {
802        if (mData.getContainerType() == MTP_CONTAINER_TYPE_RESPONSE) {
803            ALOGD("got response packet instead of data packet");
804            // we got a response packet rather than data
805            // copy it to mResponse
806            mResponse.copyFrom(mData);
807            mReceivedResponse = true;
808            return false;
809        }
810        mData.dump();
811        return true;
812    }
813    else {
814        ALOGV("readResponse failed\n");
815        return false;
816    }
817}
818
819bool MtpDevice::writeDataHeader(MtpOperationCode operation, int dataLength) {
820    mData.setOperationCode(operation);
821    mData.setTransactionID(mRequest.getTransactionID());
822    return (!mData.writeDataHeader(mRequestOut, dataLength));
823}
824
825MtpResponseCode MtpDevice::readResponse() {
826    ALOGV("readResponse\n");
827    if (mReceivedResponse) {
828        mReceivedResponse = false;
829        return mResponse.getResponseCode();
830    }
831    int ret = mResponse.read(mRequestIn1);
832    // handle zero length packets, which might occur if the data transfer
833    // ends on a packet boundary
834    if (ret == 0)
835        ret = mResponse.read(mRequestIn1);
836    if (ret >= MTP_CONTAINER_HEADER_SIZE) {
837        mResponse.dump();
838        return mResponse.getResponseCode();
839    } else {
840        ALOGD("readResponse failed\n");
841        return -1;
842    }
843}
844
845}  // namespace android
846