android_system_core/adb/transport_usb.cpp

/*
 * Copyright (C) 2007 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.
 */

#define TRACE_TAG TRANSPORT

#include "sysdeps.h"
#include "transport.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "adb.h"

static int remote_read(apacket *p, atransport *t)
{
    if(usb_read(t->usb, &p->msg, sizeof(amessage))){
        D("remote usb: read terminated (message)");
        return -1;
    }

    if(check_header(p, t)) {
        D("remote usb: check_header failed");
        return -1;
    }

    if(p->msg.data_length) {
        if(usb_read(t->usb, p->data, p->msg.data_length)){
            D("remote usb: terminated (data)");
            return -1;
        }
    }

    if(check_data(p)) {
        D("remote usb: check_data failed");
        return -1;
    }

    return 0;
}

static int remote_write(apacket *p, atransport *t)
{
    unsigned size = p->msg.data_length;

    if(usb_write(t->usb, &p->msg, sizeof(amessage))) {
        D("remote usb: 1 - write terminated");
        return -1;
    }
    if(p->msg.data_length == 0) return 0;
    if(usb_write(t->usb, &p->data, size)) {
        D("remote usb: 2 - write terminated");
        return -1;
    }

    return 0;
}

static void remote_close(atransport *t)
{
    usb_close(t->usb);
    t->usb = 0;
}

static void remote_kick(atransport *t)
{
    usb_kick(t->usb);
}

void init_usb_transport(atransport *t, usb_handle *h, ConnectionState state)
{
    D("transport: usb");
    t->close = remote_close;
    t->SetKickFunction(remote_kick);
    t->read_from_remote = remote_read;
    t->write_to_remote = remote_write;
    t->sync_token = 1;
    t->connection_state = state;
    t->type = kTransportUsb;
    t->usb = h;
}

int is_adb_interface(int usb_class, int usb_subclass, int usb_protocol)
{
    return (usb_class == ADB_CLASS && usb_subclass == ADB_SUBCLASS && usb_protocol == ADB_PROTOCOL);
}

bool should_use_libusb() {
#if defined(_WIN32) || !ADB_HOST
    return false;
#else
    static bool enable = getenv("ADB_LIBUSB") && strcmp(getenv("ADB_LIBUSB"), "1") == 0;
    return enable;
#endif
}