/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <android-base/logging.h>
#include <android-base/properties.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <linux/usb/ch9.h>
#include <linux/usb/functionfs.h>
#include <mutex>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/endian.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <vector>
#include "AsyncIO.h"
#include "MtpFfsHandle.h"
#include "mtp.h"
#define cpu_to_le16(x) htole16(x)
#define cpu_to_le32(x) htole32(x)
#define FUNCTIONFS_ENDPOINT_ALLOC _IOR('g', 231, __u32)
namespace {
constexpr char FFS_MTP_EP_IN[] = "/dev/usb-ffs/mtp/ep1";
constexpr char FFS_MTP_EP_OUT[] = "/dev/usb-ffs/mtp/ep2";
constexpr char FFS_MTP_EP_INTR[] = "/dev/usb-ffs/mtp/ep3";
constexpr int MAX_PACKET_SIZE_FS = 64;
constexpr int MAX_PACKET_SIZE_HS = 512;
constexpr int MAX_PACKET_SIZE_SS = 1024;
// Must be divisible by all max packet size values
constexpr int MAX_FILE_CHUNK_SIZE = 3145728;
// Safe values since some devices cannot handle large DMAs
// To get good performance, override these with
// higher values per device using the properties
// sys.usb.ffs.max_read and sys.usb.ffs.max_write
constexpr int USB_FFS_MAX_WRITE = MTP_BUFFER_SIZE;
constexpr int USB_FFS_MAX_READ = MTP_BUFFER_SIZE;
static_assert(USB_FFS_MAX_WRITE > 0, "Max r/w values must be > 0!");
static_assert(USB_FFS_MAX_READ > 0, "Max r/w values must be > 0!");
constexpr unsigned int MAX_MTP_FILE_SIZE = 0xFFFFFFFF;
constexpr size_t ENDPOINT_ALLOC_RETRIES = 10;
struct func_desc {
struct usb_interface_descriptor intf;
struct usb_endpoint_descriptor_no_audio sink;
struct usb_endpoint_descriptor_no_audio source;
struct usb_endpoint_descriptor_no_audio intr;
} __attribute__((packed));
struct ss_func_desc {
struct usb_interface_descriptor intf;
struct usb_endpoint_descriptor_no_audio sink;
struct usb_ss_ep_comp_descriptor sink_comp;
struct usb_endpoint_descriptor_no_audio source;
struct usb_ss_ep_comp_descriptor source_comp;
struct usb_endpoint_descriptor_no_audio intr;
struct usb_ss_ep_comp_descriptor intr_comp;
} __attribute__((packed));
struct desc_v1 {
struct usb_functionfs_descs_head_v1 {
__le32 magic;
__le32 length;
__le32 fs_count;
__le32 hs_count;
} __attribute__((packed)) header;
struct func_desc fs_descs, hs_descs;
} __attribute__((packed));
struct desc_v2 {
struct usb_functionfs_descs_head_v2 header;
// The rest of the structure depends on the flags in the header.
__le32 fs_count;
__le32 hs_count;
__le32 ss_count;
struct func_desc fs_descs, hs_descs;
struct ss_func_desc ss_descs;
} __attribute__((packed));
const struct usb_interface_descriptor mtp_interface_desc = {
.bLength = USB_DT_INTERFACE_SIZE,
.bDescriptorType = USB_DT_INTERFACE,
.bInterfaceNumber = 0,
.bNumEndpoints = 3,
.bInterfaceClass = USB_CLASS_STILL_IMAGE,
.bInterfaceSubClass = 1,
.bInterfaceProtocol = 1,
.iInterface = 1,
};
const struct usb_interface_descriptor ptp_interface_desc = {
.bLength = USB_DT_INTERFACE_SIZE,
.bDescriptorType = USB_DT_INTERFACE,
.bInterfaceNumber = 0,
.bNumEndpoints = 3,
.bInterfaceClass = USB_CLASS_STILL_IMAGE,
.bInterfaceSubClass = 1,
.bInterfaceProtocol = 1,
};
const struct usb_endpoint_descriptor_no_audio fs_sink = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 1 | USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = MAX_PACKET_SIZE_FS,
};
const struct usb_endpoint_descriptor_no_audio fs_source = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 2 | USB_DIR_OUT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = MAX_PACKET_SIZE_FS,
};
const struct usb_endpoint_descriptor_no_audio fs_intr = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 3 | USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_INT,
.wMaxPacketSize = MAX_PACKET_SIZE_FS,
.bInterval = 6,
};
const struct usb_endpoint_descriptor_no_audio hs_sink = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 1 | USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = MAX_PACKET_SIZE_HS,
};
const struct usb_endpoint_descriptor_no_audio hs_source = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 2 | USB_DIR_OUT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = MAX_PACKET_SIZE_HS,
};
const struct usb_endpoint_descriptor_no_audio hs_intr = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 3 | USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_INT,
.wMaxPacketSize = MAX_PACKET_SIZE_HS,
.bInterval = 6,
};
const struct usb_endpoint_descriptor_no_audio ss_sink = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 1 | USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = MAX_PACKET_SIZE_SS,
};
const struct usb_endpoint_descriptor_no_audio ss_source = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 2 | USB_DIR_OUT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = MAX_PACKET_SIZE_SS,
};
const struct usb_endpoint_descriptor_no_audio ss_intr = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 3 | USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_INT,
.wMaxPacketSize = MAX_PACKET_SIZE_SS,
.bInterval = 6,
};
const struct usb_ss_ep_comp_descriptor ss_sink_comp = {
.bLength = sizeof(ss_sink_comp),
.bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
.bMaxBurst = 6,
};
const struct usb_ss_ep_comp_descriptor ss_source_comp = {
.bLength = sizeof(ss_source_comp),
.bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
.bMaxBurst = 6,
};
const struct usb_ss_ep_comp_descriptor ss_intr_comp = {
.bLength = sizeof(ss_intr_comp),
.bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
};
const struct func_desc mtp_fs_descriptors = {
.intf = mtp_interface_desc,
.sink = fs_sink,
.source = fs_source,
.intr = fs_intr,
};
const struct func_desc mtp_hs_descriptors = {
.intf = mtp_interface_desc,
.sink = hs_sink,
.source = hs_source,
.intr = hs_intr,
};
const struct ss_func_desc mtp_ss_descriptors = {
.intf = mtp_interface_desc,
.sink = ss_sink,
.sink_comp = ss_sink_comp,
.source = ss_source,
.source_comp = ss_source_comp,
.intr = ss_intr,
.intr_comp = ss_intr_comp,
};
const struct func_desc ptp_fs_descriptors = {
.intf = ptp_interface_desc,
.sink = fs_sink,
.source = fs_source,
.intr = fs_intr,
};
const struct func_desc ptp_hs_descriptors = {
.intf = ptp_interface_desc,
.sink = hs_sink,
.source = hs_source,
.intr = hs_intr,
};
const struct ss_func_desc ptp_ss_descriptors = {
.intf = ptp_interface_desc,
.sink = ss_sink,
.sink_comp = ss_sink_comp,
.source = ss_source,
.source_comp = ss_source_comp,
.intr = ss_intr,
.intr_comp = ss_intr_comp,
};
#define STR_INTERFACE "MTP"
const struct {
struct usb_functionfs_strings_head header;
struct {
__le16 code;
const char str1[sizeof(STR_INTERFACE)];
} __attribute__((packed)) lang0;
} __attribute__((packed)) strings = {
.header = {
.magic = cpu_to_le32(FUNCTIONFS_STRINGS_MAGIC),
.length = cpu_to_le32(sizeof(strings)),
.str_count = cpu_to_le32(1),
.lang_count = cpu_to_le32(1),
},
.lang0 = {
.code = cpu_to_le16(0x0409),
.str1 = STR_INTERFACE,
},
};
} // anonymous namespace
namespace android {
MtpFfsHandle::MtpFfsHandle() :
mMaxWrite(USB_FFS_MAX_WRITE),
mMaxRead(USB_FFS_MAX_READ) {}
MtpFfsHandle::~MtpFfsHandle() {}
void MtpFfsHandle::closeEndpoints() {
mIntr.reset();
mBulkIn.reset();
mBulkOut.reset();
}
bool MtpFfsHandle::initFunctionfs() {
ssize_t ret;
struct desc_v1 v1_descriptor;
struct desc_v2 v2_descriptor;
v2_descriptor.header.magic = cpu_to_le32(FUNCTIONFS_DESCRIPTORS_MAGIC_V2);
v2_descriptor.header.length = cpu_to_le32(sizeof(v2_descriptor));
v2_descriptor.header.flags = FUNCTIONFS_HAS_FS_DESC | FUNCTIONFS_HAS_HS_DESC |
FUNCTIONFS_HAS_SS_DESC;
v2_descriptor.fs_count = 4;
v2_descriptor.hs_count = 4;
v2_descriptor.ss_count = 7;
v2_descriptor.fs_descs = mPtp ? ptp_fs_descriptors : mtp_fs_descriptors;
v2_descriptor.hs_descs = mPtp ? ptp_hs_descriptors : mtp_hs_descriptors;
v2_descriptor.ss_descs = mPtp ? ptp_ss_descriptors : mtp_ss_descriptors;
if (mControl < 0) { // might have already done this before
mControl.reset(TEMP_FAILURE_RETRY(open(FFS_MTP_EP0, O_RDWR)));
if (mControl < 0) {
PLOG(ERROR) << FFS_MTP_EP0 << ": cannot open control endpoint";
goto err;
}
ret = TEMP_FAILURE_RETRY(::write(mControl, &v2_descriptor, sizeof(v2_descriptor)));
if (ret < 0) {
v1_descriptor.header.magic = cpu_to_le32(FUNCTIONFS_DESCRIPTORS_MAGIC);
v1_descriptor.header.length = cpu_to_le32(sizeof(v1_descriptor));
v1_descriptor.header.fs_count = 4;
v1_descriptor.header.hs_count = 4;
v1_descriptor.fs_descs = mPtp ? ptp_fs_descriptors : mtp_fs_descriptors;
v1_descriptor.hs_descs = mPtp ? ptp_hs_descriptors : mtp_hs_descriptors;
PLOG(ERROR) << FFS_MTP_EP0 << "Switching to V1 descriptor format";
ret = TEMP_FAILURE_RETRY(::write(mControl, &v1_descriptor, sizeof(v1_descriptor)));
if (ret < 0) {
PLOG(ERROR) << FFS_MTP_EP0 << "Writing descriptors failed";
goto err;
}
}
ret = TEMP_FAILURE_RETRY(::write(mControl, &strings, sizeof(strings)));
if (ret < 0) {
PLOG(ERROR) << FFS_MTP_EP0 << "Writing strings failed";
goto err;
}
}
if (mBulkIn > -1 || mBulkOut > -1 || mIntr > -1)
LOG(WARNING) << "Endpoints were not closed before configure!";
return true;
err:
closeConfig();
return false;
}
void MtpFfsHandle::closeConfig() {
mControl.reset();
}
int MtpFfsHandle::writeHandle(int fd, const void* data, int len) {
LOG(VERBOSE) << "MTP about to write fd = " << fd << ", len=" << len;
int ret = 0;
const char* buf = static_cast<const char*>(data);
while (len > 0) {
int write_len = std::min(mMaxWrite, len);
int n = TEMP_FAILURE_RETRY(::write(fd, buf, write_len));
if (n < 0) {
PLOG(ERROR) << "write ERROR: fd = " << fd << ", n = " << n;
return -1;
} else if (n < write_len) {
errno = EIO;
PLOG(ERROR) << "less written than expected";
return -1;
}
buf += n;
len -= n;
ret += n;
}
return ret;
}
int MtpFfsHandle::readHandle(int fd, void* data, int len) {
LOG(VERBOSE) << "MTP about to read fd = " << fd << ", len=" << len;
int ret = 0;
char* buf = static_cast<char*>(data);
while (len > 0) {
int read_len = std::min(mMaxRead, len);
int n = TEMP_FAILURE_RETRY(::read(fd, buf, read_len));
if (n < 0) {
PLOG(ERROR) << "read ERROR: fd = " << fd << ", n = " << n;
return -1;
}
ret += n;
if (n < read_len) // done reading early
break;
buf += n;
len -= n;
}
return ret;
}
int MtpFfsHandle::spliceReadHandle(int fd, int pipe_out, int len) {
LOG(VERBOSE) << "MTP about to splice read fd = " << fd << ", len=" << len;
int ret = 0;
loff_t dummyoff;
while (len > 0) {
int read_len = std::min(mMaxRead, len);
dummyoff = 0;
int n = TEMP_FAILURE_RETRY(splice(fd, &dummyoff, pipe_out, nullptr, read_len, 0));
if (n < 0) {
PLOG(ERROR) << "splice read ERROR: fd = " << fd << ", n = " << n;
return -1;
}
ret += n;
if (n < read_len) // done reading early
break;
len -= n;
}
return ret;
}
int MtpFfsHandle::read(void* data, int len) {
return readHandle(mBulkOut, data, len);
}
int MtpFfsHandle::write(const void* data, int len) {
return writeHandle(mBulkIn, data, len);
}
int MtpFfsHandle::start() {
mLock.lock();
mBulkIn.reset(TEMP_FAILURE_RETRY(open(FFS_MTP_EP_IN, O_RDWR)));
if (mBulkIn < 0) {
PLOG(ERROR) << FFS_MTP_EP_IN << ": cannot open bulk in ep";
return -1;
}
mBulkOut.reset(TEMP_FAILURE_RETRY(open(FFS_MTP_EP_OUT, O_RDWR)));
if (mBulkOut < 0) {
PLOG(ERROR) << FFS_MTP_EP_OUT << ": cannot open bulk out ep";
return -1;
}
mIntr.reset(TEMP_FAILURE_RETRY(open(FFS_MTP_EP_INTR, O_RDWR)));
if (mIntr < 0) {
PLOG(ERROR) << FFS_MTP_EP0 << ": cannot open intr ep";
return -1;
}
mBuffer1.resize(MAX_FILE_CHUNK_SIZE);
mBuffer2.resize(MAX_FILE_CHUNK_SIZE);
posix_madvise(mBuffer1.data(), MAX_FILE_CHUNK_SIZE,
POSIX_MADV_SEQUENTIAL | POSIX_MADV_WILLNEED);
posix_madvise(mBuffer2.data(), MAX_FILE_CHUNK_SIZE,
POSIX_MADV_SEQUENTIAL | POSIX_MADV_WILLNEED);
// Get device specific r/w size
mMaxWrite = android::base::GetIntProperty("sys.usb.ffs.max_write", USB_FFS_MAX_WRITE);
mMaxRead = android::base::GetIntProperty("sys.usb.ffs.max_read", USB_FFS_MAX_READ);
size_t attempts = 0;
while (mMaxWrite >= USB_FFS_MAX_WRITE && mMaxRead >= USB_FFS_MAX_READ &&
attempts < ENDPOINT_ALLOC_RETRIES) {
// If larger contiguous chunks of memory aren't available, attempt to try
// smaller allocations.
if (ioctl(mBulkIn, FUNCTIONFS_ENDPOINT_ALLOC, static_cast<__u32>(mMaxWrite)) ||
ioctl(mBulkOut, FUNCTIONFS_ENDPOINT_ALLOC, static_cast<__u32>(mMaxRead))) {
if (errno == ENODEV) {
// Driver hasn't enabled endpoints yet.
std::this_thread::sleep_for(std::chrono::milliseconds(100));
attempts += 1;
continue;
}
mMaxWrite /= 2;
mMaxRead /=2;
} else {
return 0;
}
}
// Try to start MtpServer anyway, with the smallest max r/w values
PLOG(ERROR) << "Functionfs could not allocate any memory!";
return 0;
}
int MtpFfsHandle::configure(bool usePtp) {
// Wait till previous server invocation has closed
if (!mLock.try_lock_for(std::chrono::milliseconds(1000))) {
LOG(ERROR) << "MtpServer was unable to get configure lock";
return -1;
}
int ret = 0;
// If ptp is changed, the configuration must be rewritten
if (mPtp != usePtp) {
closeEndpoints();
closeConfig();
}
mPtp = usePtp;
if (!initFunctionfs()) {
ret = -1;
}
mLock.unlock();
return ret;
}
void MtpFfsHandle::close() {
closeEndpoints();
mLock.unlock();
}
/* Read from USB and write to a local file. */
int MtpFfsHandle::receiveFile(mtp_file_range mfr, bool zero_packet) {
// When receiving files, the incoming length is given in 32 bits.
// A >4G file is given as 0xFFFFFFFF
uint32_t file_length = mfr.length;
uint64_t offset = mfr.offset;
struct usb_endpoint_descriptor mBulkOut_desc;
int packet_size;
if (ioctl(mBulkOut, FUNCTIONFS_ENDPOINT_DESC, reinterpret_cast<unsigned long>(&mBulkOut_desc))) {
PLOG(ERROR) << "Could not get FFS bulk-out descriptor";
packet_size = MAX_PACKET_SIZE_HS;
} else {
packet_size = mBulkOut_desc.wMaxPacketSize;
}
char *data = mBuffer1.data();
char *data2 = mBuffer2.data();
struct aiocb aio;
aio.aio_fildes = mfr.fd;
aio.aio_buf = nullptr;
struct aiocb *aiol[] = {&aio};
int ret = -1;
size_t length;
bool read = false;
bool write = false;
posix_fadvise(mfr.fd, 0, 0, POSIX_FADV_SEQUENTIAL | POSIX_FADV_NOREUSE);
// Break down the file into pieces that fit in buffers
while (file_length > 0 || write) {
if (file_length > 0) {
length = std::min(static_cast<uint32_t>(MAX_FILE_CHUNK_SIZE), file_length);
// Read data from USB, handle errors after waiting for write thread.
ret = readHandle(mBulkOut, data, length);
if (file_length != MAX_MTP_FILE_SIZE && ret < static_cast<int>(length)) {
ret = -1;
errno = EIO;
}
read = true;
}
if (write) {
// get the return status of the last write request
aio_suspend(aiol, 1, nullptr);
int written = aio_return(&aio);
if (written == -1) {
errno = aio_error(&aio);
return -1;
}
if (static_cast<size_t>(written) < aio.aio_nbytes) {
errno = EIO;
return -1;
}
write = false;
}
// If there was an error reading above
if (ret == -1) {
return -1;
}
if (read) {
if (file_length == MAX_MTP_FILE_SIZE) {
// For larger files, receive until a short packet is received.
if (static_cast<size_t>(ret) < length) {
file_length = 0;
}
} else {
// Receive an empty packet if size is a multiple of the endpoint size.
file_length -= ret;
}
// Enqueue a new write request
aio.aio_buf = data;
aio.aio_sink = mfr.fd;
aio.aio_offset = offset;
aio.aio_nbytes = ret;
aio_write(&aio);
offset += ret;
std::swap(data, data2);
write = true;
read = false;
}
}
if (ret % packet_size == 0 || zero_packet) {
if (TEMP_FAILURE_RETRY(::read(mBulkOut, data, packet_size)) != 0) {
return -1;
}
}
return 0;
}
/* Read from a local file and send over USB. */
int MtpFfsHandle::sendFile(mtp_file_range mfr) {
uint64_t file_length = mfr.length;
uint32_t given_length = std::min(static_cast<uint64_t>(MAX_MTP_FILE_SIZE),
file_length + sizeof(mtp_data_header));
uint64_t offset = mfr.offset;
struct usb_endpoint_descriptor mBulkIn_desc;
int packet_size;
if (ioctl(mBulkIn, FUNCTIONFS_ENDPOINT_DESC, reinterpret_cast<unsigned long>(&mBulkIn_desc))) {
PLOG(ERROR) << "Could not get FFS bulk-in descriptor";
packet_size = MAX_PACKET_SIZE_HS;
} else {
packet_size = mBulkIn_desc.wMaxPacketSize;
}
// If file_length is larger than a size_t, truncating would produce the wrong comparison.
// Instead, promote the left side to 64 bits, then truncate the small result.
int init_read_len = std::min(
static_cast<uint64_t>(packet_size - sizeof(mtp_data_header)), file_length);
char *data = mBuffer1.data();
char *data2 = mBuffer2.data();
posix_fadvise(mfr.fd, 0, 0, POSIX_FADV_SEQUENTIAL | POSIX_FADV_NOREUSE);
struct aiocb aio;
aio.aio_fildes = mfr.fd;
struct aiocb *aiol[] = {&aio};
int ret, length;
int error = 0;
bool read = false;
bool write = false;
// Send the header data
mtp_data_header *header = reinterpret_cast<mtp_data_header*>(data);
header->length = __cpu_to_le32(given_length);
header->type = __cpu_to_le16(2); /* data packet */
header->command = __cpu_to_le16(mfr.command);
header->transaction_id = __cpu_to_le32(mfr.transaction_id);
// Some hosts don't support header/data separation even though MTP allows it
// Handle by filling first packet with initial file data
if (TEMP_FAILURE_RETRY(pread(mfr.fd, reinterpret_cast<char*>(data) +
sizeof(mtp_data_header), init_read_len, offset))
!= init_read_len) return -1;
if (writeHandle(mBulkIn, data, sizeof(mtp_data_header) + init_read_len) == -1) return -1;
file_length -= init_read_len;
offset += init_read_len;
ret = init_read_len + sizeof(mtp_data_header);
// Break down the file into pieces that fit in buffers
while(file_length > 0) {
if (read) {
// Wait for the previous read to finish
aio_suspend(aiol, 1, nullptr);
ret = aio_return(&aio);
if (ret == -1) {
errno = aio_error(&aio);
return -1;
}
if (static_cast<size_t>(ret) < aio.aio_nbytes) {
errno = EIO;
return -1;
}
file_length -= ret;
offset += ret;
std::swap(data, data2);
read = false;
write = true;
}
if (error == -1) {
return -1;
}
if (file_length > 0) {
length = std::min(static_cast<uint64_t>(MAX_FILE_CHUNK_SIZE), file_length);
// Queue up another read
aio.aio_buf = data;
aio.aio_offset = offset;
aio.aio_nbytes = length;
aio_read(&aio);
read = true;
}
if (write) {
if (writeHandle(mBulkIn, data2, ret) == -1) {
error = -1;
}
write = false;
}
}
if (ret % packet_size == 0) {
// If the last packet wasn't short, send a final empty packet
if (TEMP_FAILURE_RETRY(::write(mBulkIn, data, 0)) != 0) {
return -1;
}
}
return 0;
}
int MtpFfsHandle::sendEvent(mtp_event me) {
unsigned length = me.length;
int ret = writeHandle(mIntr, me.data, length);
return static_cast<unsigned>(ret) == length ? 0 : -1;
}
} // namespace android
IMtpHandle *get_ffs_handle() {
return new android::MtpFfsHandle();
}