MtpDevice.cpp revision 3ab368e0810d894dcbc0971350c095049478a055 
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        info->read(mData);
317        return info;
318    }
319    return NULL;
320}
321
322MtpStorageIDList* MtpDevice::getStorageIDs() {
323    Mutex::Autolock autoLock(mMutex);
324
325    mRequest.reset();
326    if (!sendRequest(MTP_OPERATION_GET_STORAGE_IDS))
327        return NULL;
328    if (!readData())
329        return NULL;
330    MtpResponseCode ret = readResponse();
331    if (ret == MTP_RESPONSE_OK) {
332        return mData.getAUInt32();
333    }
334    return NULL;
335}
336
337MtpStorageInfo* MtpDevice::getStorageInfo(MtpStorageID storageID) {
338    Mutex::Autolock autoLock(mMutex);
339
340    mRequest.reset();
341    mRequest.setParameter(1, storageID);
342    if (!sendRequest(MTP_OPERATION_GET_STORAGE_INFO))
343        return NULL;
344    if (!readData())
345        return NULL;
346    MtpResponseCode ret = readResponse();
347    if (ret == MTP_RESPONSE_OK) {
348        MtpStorageInfo* info = new MtpStorageInfo(storageID);
349        info->read(mData);
350        return info;
351    }
352    return NULL;
353}
354
355MtpObjectHandleList* MtpDevice::getObjectHandles(MtpStorageID storageID,
356            MtpObjectFormat format, MtpObjectHandle parent) {
357    Mutex::Autolock autoLock(mMutex);
358
359    mRequest.reset();
360    mRequest.setParameter(1, storageID);
361    mRequest.setParameter(2, format);
362    mRequest.setParameter(3, parent);
363    if (!sendRequest(MTP_OPERATION_GET_OBJECT_HANDLES))
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
374MtpObjectInfo* MtpDevice::getObjectInfo(MtpObjectHandle handle) {
375    Mutex::Autolock autoLock(mMutex);
376
377    // FIXME - we might want to add some caching here
378
379    mRequest.reset();
380    mRequest.setParameter(1, handle);
381    if (!sendRequest(MTP_OPERATION_GET_OBJECT_INFO))
382        return NULL;
383    if (!readData())
384        return NULL;
385    MtpResponseCode ret = readResponse();
386    if (ret == MTP_RESPONSE_OK) {
387        MtpObjectInfo* info = new MtpObjectInfo(handle);
388        info->read(mData);
389        return info;
390    }
391    return NULL;
392}
393
394void* MtpDevice::getThumbnail(MtpObjectHandle handle, int& outLength) {
395    Mutex::Autolock autoLock(mMutex);
396
397    mRequest.reset();
398    mRequest.setParameter(1, handle);
399    if (sendRequest(MTP_OPERATION_GET_THUMB) && readData()) {
400        MtpResponseCode ret = readResponse();
401        if (ret == MTP_RESPONSE_OK) {
402            return mData.getData(outLength);
403        }
404    }
405    outLength = 0;
406    return NULL;
407}
408
409MtpObjectHandle MtpDevice::sendObjectInfo(MtpObjectInfo* info) {
410    Mutex::Autolock autoLock(mMutex);
411
412    mRequest.reset();
413    MtpObjectHandle parent = info->mParent;
414    if (parent == 0)
415        parent = MTP_PARENT_ROOT;
416
417    mRequest.setParameter(1, info->mStorageID);
418    mRequest.setParameter(2, info->mParent);
419
420    mData.putUInt32(info->mStorageID);
421    mData.putUInt16(info->mFormat);
422    mData.putUInt16(info->mProtectionStatus);
423    mData.putUInt32(info->mCompressedSize);
424    mData.putUInt16(info->mThumbFormat);
425    mData.putUInt32(info->mThumbCompressedSize);
426    mData.putUInt32(info->mThumbPixWidth);
427    mData.putUInt32(info->mThumbPixHeight);
428    mData.putUInt32(info->mImagePixWidth);
429    mData.putUInt32(info->mImagePixHeight);
430    mData.putUInt32(info->mImagePixDepth);
431    mData.putUInt32(info->mParent);
432    mData.putUInt16(info->mAssociationType);
433    mData.putUInt32(info->mAssociationDesc);
434    mData.putUInt32(info->mSequenceNumber);
435    mData.putString(info->mName);
436
437    char created[100], modified[100];
438    formatDateTime(info->mDateCreated, created, sizeof(created));
439    formatDateTime(info->mDateModified, modified, sizeof(modified));
440
441    mData.putString(created);
442    mData.putString(modified);
443    if (info->mKeywords)
444        mData.putString(info->mKeywords);
445    else
446        mData.putEmptyString();
447
448   if (sendRequest(MTP_OPERATION_SEND_OBJECT_INFO) && sendData()) {
449        MtpResponseCode ret = readResponse();
450        if (ret == MTP_RESPONSE_OK) {
451            info->mStorageID = mResponse.getParameter(1);
452            info->mParent = mResponse.getParameter(2);
453            info->mHandle = mResponse.getParameter(3);
454            return info->mHandle;
455        }
456    }
457    return (MtpObjectHandle)-1;
458}
459
460bool MtpDevice::sendObject(MtpObjectInfo* info, int srcFD) {
461    Mutex::Autolock autoLock(mMutex);
462
463    int remaining = info->mCompressedSize;
464    mRequest.reset();
465    mRequest.setParameter(1, info->mHandle);
466    if (sendRequest(MTP_OPERATION_SEND_OBJECT)) {
467        // send data header
468        writeDataHeader(MTP_OPERATION_SEND_OBJECT, remaining);
469
470        char buffer[65536];
471        while (remaining > 0) {
472            int count = read(srcFD, buffer, sizeof(buffer));
473            if (count > 0) {
474                int written = mData.write(mRequestOut, buffer, count);
475                // FIXME check error
476                remaining -= count;
477            } else {
478                break;
479            }
480        }
481    }
482    MtpResponseCode ret = readResponse();
483    return (remaining == 0 && ret == MTP_RESPONSE_OK);
484}
485
486bool MtpDevice::deleteObject(MtpObjectHandle handle) {
487    Mutex::Autolock autoLock(mMutex);
488
489    mRequest.reset();
490    mRequest.setParameter(1, handle);
491    if (sendRequest(MTP_OPERATION_DELETE_OBJECT)) {
492        MtpResponseCode ret = readResponse();
493        if (ret == MTP_RESPONSE_OK)
494            return true;
495    }
496    return false;
497}
498
499MtpObjectHandle MtpDevice::getParent(MtpObjectHandle handle) {
500    MtpObjectInfo* info = getObjectInfo(handle);
501    if (info) {
502        MtpObjectHandle parent = info->mParent;
503        delete info;
504        return parent;
505    } else {
506        return -1;
507    }
508}
509
510MtpObjectHandle MtpDevice::getStorageID(MtpObjectHandle handle) {
511    MtpObjectInfo* info = getObjectInfo(handle);
512    if (info) {
513        MtpObjectHandle storageId = info->mStorageID;
514        delete info;
515        return storageId;
516    } else {
517        return -1;
518    }
519}
520
521MtpObjectPropertyList* MtpDevice::getObjectPropsSupported(MtpObjectFormat format) {
522    Mutex::Autolock autoLock(mMutex);
523
524    mRequest.reset();
525    mRequest.setParameter(1, format);
526    if (!sendRequest(MTP_OPERATION_GET_OBJECT_PROPS_SUPPORTED))
527        return NULL;
528    if (!readData())
529        return NULL;
530    MtpResponseCode ret = readResponse();
531    if (ret == MTP_RESPONSE_OK) {
532        return mData.getAUInt16();
533    }
534    return NULL;
535
536}
537
538MtpProperty* MtpDevice::getDevicePropDesc(MtpDeviceProperty code) {
539    Mutex::Autolock autoLock(mMutex);
540
541    mRequest.reset();
542    mRequest.setParameter(1, code);
543    if (!sendRequest(MTP_OPERATION_GET_DEVICE_PROP_DESC))
544        return NULL;
545    if (!readData())
546        return NULL;
547    MtpResponseCode ret = readResponse();
548    if (ret == MTP_RESPONSE_OK) {
549        MtpProperty* property = new MtpProperty;
550        property->read(mData);
551        return property;
552    }
553    return NULL;
554}
555
556MtpProperty* MtpDevice::getObjectPropDesc(MtpObjectProperty code, MtpObjectFormat format) {
557    Mutex::Autolock autoLock(mMutex);
558
559    mRequest.reset();
560    mRequest.setParameter(1, code);
561    mRequest.setParameter(2, format);
562    if (!sendRequest(MTP_OPERATION_GET_OBJECT_PROP_DESC))
563        return NULL;
564    if (!readData())
565        return NULL;
566    MtpResponseCode ret = readResponse();
567    if (ret == MTP_RESPONSE_OK) {
568        MtpProperty* property = new MtpProperty;
569        property->read(mData);
570        return property;
571    }
572    return NULL;
573}
574
575bool MtpDevice::readObject(MtpObjectHandle handle,
576        bool (* callback)(void* data, int offset, int length, void* clientData),
577        int objectSize, void* clientData) {
578    Mutex::Autolock autoLock(mMutex);
579    bool result = false;
580
581    mRequest.reset();
582    mRequest.setParameter(1, handle);
583    if (sendRequest(MTP_OPERATION_GET_OBJECT)
584            && mData.readDataHeader(mRequestIn1)) {
585        uint32_t length = mData.getContainerLength();
586        if (length - MTP_CONTAINER_HEADER_SIZE != objectSize) {
587            ALOGE("readObject error objectSize: %d, length: %d",
588                    objectSize, length);
589            goto fail;
590        }
591        length -= MTP_CONTAINER_HEADER_SIZE;
592        uint32_t remaining = length;
593        int offset = 0;
594
595        int initialDataLength = 0;
596        void* initialData = mData.getData(initialDataLength);
597        if (initialData) {
598            if (initialDataLength > 0) {
599                if (!callback(initialData, 0, initialDataLength, clientData))
600                    goto fail;
601                remaining -= initialDataLength;
602                offset += initialDataLength;
603            }
604            free(initialData);
605        }
606
607        // USB reads greater than 16K don't work
608        char buffer1[16384], buffer2[16384];
609        mRequestIn1->buffer = buffer1;
610        mRequestIn2->buffer = buffer2;
611        struct usb_request* req = mRequestIn1;
612        void* writeBuffer = NULL;
613        int writeLength = 0;
614
615        while (remaining > 0 || writeBuffer) {
616            if (remaining > 0) {
617                // queue up a read request
618                req->buffer_length = (remaining > sizeof(buffer1) ? sizeof(buffer1) : remaining);
619                if (mData.readDataAsync(req)) {
620                    ALOGE("readDataAsync failed");
621                    goto fail;
622                }
623            } else {
624                req = NULL;
625            }
626
627            if (writeBuffer) {
628                // write previous buffer
629                if (!callback(writeBuffer, offset, writeLength, clientData)) {
630                    ALOGE("write failed");
631                    // wait for pending read before failing
632                    if (req)
633                        mData.readDataWait(mDevice);
634                    goto fail;
635                }
636                offset += writeLength;
637                writeBuffer = NULL;
638            }
639
640            // wait for read to complete
641            if (req) {
642                int read = mData.readDataWait(mDevice);
643                if (read < 0)
644                    goto fail;
645
646                if (read > 0) {
647                    writeBuffer = req->buffer;
648                    writeLength = read;
649                    remaining -= read;
650                    req = (req == mRequestIn1 ? mRequestIn2 : mRequestIn1);
651                } else {
652                    writeBuffer = NULL;
653                }
654            }
655        }
656
657        MtpResponseCode response = readResponse();
658        if (response == MTP_RESPONSE_OK)
659            result = true;
660    }
661
662fail:
663    return result;
664}
665
666
667// reads the object's data and writes it to the specified file path
668bool MtpDevice::readObject(MtpObjectHandle handle, const char* destPath, int group, int perm) {
669    ALOGD("readObject: %s", destPath);
670    int fd = ::open(destPath, O_RDWR | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR);
671    if (fd < 0) {
672        ALOGE("open failed for %s", destPath);
673        return false;
674    }
675
676    fchown(fd, getuid(), group);
677    // set permissions
678    int mask = umask(0);
679    fchmod(fd, perm);
680    umask(mask);
681
682    Mutex::Autolock autoLock(mMutex);
683    bool result = false;
684
685    mRequest.reset();
686    mRequest.setParameter(1, handle);
687    if (sendRequest(MTP_OPERATION_GET_OBJECT)
688            && mData.readDataHeader(mRequestIn1)) {
689        uint32_t length = mData.getContainerLength();
690        if (length < MTP_CONTAINER_HEADER_SIZE)
691            goto fail;
692        length -= MTP_CONTAINER_HEADER_SIZE;
693        uint32_t remaining = length;
694
695        int initialDataLength = 0;
696        void* initialData = mData.getData(initialDataLength);
697        if (initialData) {
698            if (initialDataLength > 0) {
699                if (write(fd, initialData, initialDataLength) != initialDataLength) {
700                    free(initialData);
701                    goto fail;
702                }
703                remaining -= initialDataLength;
704            }
705            free(initialData);
706        }
707
708        // USB reads greater than 16K don't work
709        char buffer1[16384], buffer2[16384];
710        mRequestIn1->buffer = buffer1;
711        mRequestIn2->buffer = buffer2;
712        struct usb_request* req = mRequestIn1;
713        void* writeBuffer = NULL;
714        int writeLength = 0;
715
716        while (remaining > 0 || writeBuffer) {
717            if (remaining > 0) {
718                // queue up a read request
719                req->buffer_length = (remaining > sizeof(buffer1) ? sizeof(buffer1) : remaining);
720                if (mData.readDataAsync(req)) {
721                    ALOGE("readDataAsync failed");
722                    goto fail;
723                }
724            } else {
725                req = NULL;
726            }
727
728            if (writeBuffer) {
729                // write previous buffer
730                if (write(fd, writeBuffer, writeLength) != writeLength) {
731                    ALOGE("write failed");
732                    // wait for pending read before failing
733                    if (req)
734                        mData.readDataWait(mDevice);
735                    goto fail;
736                }
737                writeBuffer = NULL;
738            }
739
740            // wait for read to complete
741            if (req) {
742                int read = mData.readDataWait(mDevice);
743                if (read < 0)
744                    goto fail;
745
746                if (read > 0) {
747                    writeBuffer = req->buffer;
748                    writeLength = read;
749                    remaining -= read;
750                    req = (req == mRequestIn1 ? mRequestIn2 : mRequestIn1);
751                } else {
752                    writeBuffer = NULL;
753                }
754            }
755        }
756
757        MtpResponseCode response = readResponse();
758        if (response == MTP_RESPONSE_OK)
759            result = true;
760    }
761
762fail:
763    ::close(fd);
764    return result;
765}
766
767bool MtpDevice::sendRequest(MtpOperationCode operation) {
768    ALOGV("sendRequest: %s\n", MtpDebug::getOperationCodeName(operation));
769    mReceivedResponse = false;
770    mRequest.setOperationCode(operation);
771    if (mTransactionID > 0)
772        mRequest.setTransactionID(mTransactionID++);
773    int ret = mRequest.write(mRequestOut);
774    mRequest.dump();
775    return (ret > 0);
776}
777
778bool MtpDevice::sendData() {
779    ALOGV("sendData\n");
780    mData.setOperationCode(mRequest.getOperationCode());
781    mData.setTransactionID(mRequest.getTransactionID());
782    int ret = mData.write(mRequestOut);
783    mData.dump();
784    return (ret > 0);
785}
786
787bool MtpDevice::readData() {
788    mData.reset();
789    int ret = mData.read(mRequestIn1);
790    ALOGV("readData returned %d\n", ret);
791    if (ret >= MTP_CONTAINER_HEADER_SIZE) {
792        if (mData.getContainerType() == MTP_CONTAINER_TYPE_RESPONSE) {
793            ALOGD("got response packet instead of data packet");
794            // we got a response packet rather than data
795            // copy it to mResponse
796            mResponse.copyFrom(mData);
797            mReceivedResponse = true;
798            return false;
799        }
800        mData.dump();
801        return true;
802    }
803    else {
804        ALOGV("readResponse failed\n");
805        return false;
806    }
807}
808
809bool MtpDevice::writeDataHeader(MtpOperationCode operation, int dataLength) {
810    mData.setOperationCode(operation);
811    mData.setTransactionID(mRequest.getTransactionID());
812    return (!mData.writeDataHeader(mRequestOut, dataLength));
813}
814
815MtpResponseCode MtpDevice::readResponse() {
816    ALOGV("readResponse\n");
817    if (mReceivedResponse) {
818        mReceivedResponse = false;
819        return mResponse.getResponseCode();
820    }
821    int ret = mResponse.read(mRequestIn1);
822    // handle zero length packets, which might occur if the data transfer
823    // ends on a packet boundary
824    if (ret == 0)
825        ret = mResponse.read(mRequestIn1);
826    if (ret >= MTP_CONTAINER_HEADER_SIZE) {
827        mResponse.dump();
828        return mResponse.getResponseCode();
829    } else {
830        ALOGD("readResponse failed\n");
831        return -1;
832    }
833}
834
835}  // namespace android
836