transport.cpp revision dcd78a15d0be143d48fc93af6a9fa5748dbf9790 
1/*
2 * Copyright (C) 2007 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 TRACE_TAG TRACE_TRANSPORT
18
19#include "sysdeps.h"
20#include "transport.h"
21
22#include <ctype.h>
23#include <errno.h>
24#include <stdio.h>
25#include <stdlib.h>
26#include <string.h>
27#include <unistd.h>
28
29#include <base/stringprintf.h>
30
31#include "adb.h"
32#include "adb_utils.h"
33
34static void transport_unref(atransport *t);
35
36static atransport transport_list = {
37    .next = &transport_list,
38    .prev = &transport_list,
39};
40
41static atransport pending_list = {
42    .next = &pending_list,
43    .prev = &pending_list,
44};
45
46ADB_MUTEX_DEFINE( transport_lock );
47
48void kick_transport(atransport* t)
49{
50    if (t && !t->kicked)
51    {
52        int  kicked;
53
54        adb_mutex_lock(&transport_lock);
55        kicked = t->kicked;
56        if (!kicked)
57            t->kicked = 1;
58        adb_mutex_unlock(&transport_lock);
59
60        if (!kicked)
61            t->kick(t);
62    }
63}
64
65// Each atransport contains a list of adisconnects (t->disconnects).
66// An adisconnect contains a link to the next/prev adisconnect, a function
67// pointer to a disconnect callback which takes a void* piece of user data and
68// the atransport, and some user data for the callback (helpfully named
69// "opaque").
70//
71// The list is circular. New items are added to the entry member of the list
72// (t->disconnects) by add_transport_disconnect.
73//
74// run_transport_disconnects invokes each function in the list.
75//
76// Gotchas:
77//   * run_transport_disconnects assumes that t->disconnects is non-null, so
78//     this can't be run on a zeroed atransport.
79//   * The callbacks in this list are not removed when called, and this function
80//     is not guarded against running more than once. As such, ensure that this
81//     function is not called multiple times on the same atransport.
82//     TODO(danalbert): Just fix this so that it is guarded once you have tests.
83void run_transport_disconnects(atransport* t)
84{
85    adisconnect*  dis = t->disconnects.next;
86
87    D("%s: run_transport_disconnects\n", t->serial);
88    while (dis != &t->disconnects) {
89        adisconnect*  next = dis->next;
90        dis->func( dis->opaque, t );
91        dis = next;
92    }
93}
94
95static void dump_packet(const char* name, const char* func, apacket* p) {
96    unsigned  command = p->msg.command;
97    int       len     = p->msg.data_length;
98    char      cmd[9];
99    char      arg0[12], arg1[12];
100    int       n;
101
102    for (n = 0; n < 4; n++) {
103        int  b = (command >> (n*8)) & 255;
104        if (b < 32 || b >= 127)
105            break;
106        cmd[n] = (char)b;
107    }
108    if (n == 4) {
109        cmd[4] = 0;
110    } else {
111        /* There is some non-ASCII name in the command, so dump
112            * the hexadecimal value instead */
113        snprintf(cmd, sizeof cmd, "%08x", command);
114    }
115
116    if (p->msg.arg0 < 256U)
117        snprintf(arg0, sizeof arg0, "%d", p->msg.arg0);
118    else
119        snprintf(arg0, sizeof arg0, "0x%x", p->msg.arg0);
120
121    if (p->msg.arg1 < 256U)
122        snprintf(arg1, sizeof arg1, "%d", p->msg.arg1);
123    else
124        snprintf(arg1, sizeof arg1, "0x%x", p->msg.arg1);
125
126    D("%s: %s: [%s] arg0=%s arg1=%s (len=%d) ",
127        name, func, cmd, arg0, arg1, len);
128    dump_hex(p->data, len);
129}
130
131static int
132read_packet(int  fd, const char* name, apacket** ppacket)
133{
134    char *p = (char*)ppacket;  /* really read a packet address */
135    int   r;
136    int   len = sizeof(*ppacket);
137    char  buff[8];
138    if (!name) {
139        snprintf(buff, sizeof buff, "fd=%d", fd);
140        name = buff;
141    }
142    while(len > 0) {
143        r = adb_read(fd, p, len);
144        if(r > 0) {
145            len -= r;
146            p   += r;
147        } else {
148            D("%s: read_packet (fd=%d), error ret=%d errno=%d: %s\n", name, fd, r, errno, strerror(errno));
149            if((r < 0) && (errno == EINTR)) continue;
150            return -1;
151        }
152    }
153
154    if (ADB_TRACING) {
155        dump_packet(name, "from remote", *ppacket);
156    }
157    return 0;
158}
159
160static int
161write_packet(int  fd, const char* name, apacket** ppacket)
162{
163    char *p = (char*) ppacket;  /* we really write the packet address */
164    int r, len = sizeof(ppacket);
165    char buff[8];
166    if (!name) {
167        snprintf(buff, sizeof buff, "fd=%d", fd);
168        name = buff;
169    }
170
171    if (ADB_TRACING) {
172        dump_packet(name, "to remote", *ppacket);
173    }
174    len = sizeof(ppacket);
175    while(len > 0) {
176        r = adb_write(fd, p, len);
177        if(r > 0) {
178            len -= r;
179            p += r;
180        } else {
181            D("%s: write_packet (fd=%d) error ret=%d errno=%d: %s\n", name, fd, r, errno, strerror(errno));
182            if((r < 0) && (errno == EINTR)) continue;
183            return -1;
184        }
185    }
186    return 0;
187}
188
189static void transport_socket_events(int fd, unsigned events, void *_t)
190{
191    atransport *t = reinterpret_cast<atransport*>(_t);
192    D("transport_socket_events(fd=%d, events=%04x,...)\n", fd, events);
193    if(events & FDE_READ){
194        apacket *p = 0;
195        if(read_packet(fd, t->serial, &p)){
196            D("%s: failed to read packet from transport socket on fd %d\n", t->serial, fd);
197        } else {
198            handle_packet(p, (atransport *) _t);
199        }
200    }
201}
202
203void send_packet(apacket *p, atransport *t)
204{
205    unsigned char *x;
206    unsigned sum;
207    unsigned count;
208
209    p->msg.magic = p->msg.command ^ 0xffffffff;
210
211    count = p->msg.data_length;
212    x = (unsigned char *) p->data;
213    sum = 0;
214    while(count-- > 0){
215        sum += *x++;
216    }
217    p->msg.data_check = sum;
218
219    print_packet("send", p);
220
221    if (t == NULL) {
222        D("Transport is null \n");
223        // Zap errno because print_packet() and other stuff have errno effect.
224        errno = 0;
225        fatal_errno("Transport is null");
226    }
227
228    if(write_packet(t->transport_socket, t->serial, &p)){
229        fatal_errno("cannot enqueue packet on transport socket");
230    }
231}
232
233/* The transport is opened by transport_register_func before
234** the input and output threads are started.
235**
236** The output thread issues a SYNC(1, token) message to let
237** the input thread know to start things up.  In the event
238** of transport IO failure, the output thread will post a
239** SYNC(0,0) message to ensure shutdown.
240**
241** The transport will not actually be closed until both
242** threads exit, but the input thread will kick the transport
243** on its way out to disconnect the underlying device.
244*/
245
246static void *output_thread(void *_t)
247{
248    atransport *t = reinterpret_cast<atransport*>(_t);
249    apacket *p;
250
251    D("%s: starting transport output thread on fd %d, SYNC online (%d)\n",
252       t->serial, t->fd, t->sync_token + 1);
253    p = get_apacket();
254    p->msg.command = A_SYNC;
255    p->msg.arg0 = 1;
256    p->msg.arg1 = ++(t->sync_token);
257    p->msg.magic = A_SYNC ^ 0xffffffff;
258    if(write_packet(t->fd, t->serial, &p)) {
259        put_apacket(p);
260        D("%s: failed to write SYNC packet\n", t->serial);
261        goto oops;
262    }
263
264    D("%s: data pump started\n", t->serial);
265    for(;;) {
266        p = get_apacket();
267
268        if(t->read_from_remote(p, t) == 0){
269            D("%s: received remote packet, sending to transport\n",
270              t->serial);
271            if(write_packet(t->fd, t->serial, &p)){
272                put_apacket(p);
273                D("%s: failed to write apacket to transport\n", t->serial);
274                goto oops;
275            }
276        } else {
277            D("%s: remote read failed for transport\n", t->serial);
278            put_apacket(p);
279            break;
280        }
281    }
282
283    D("%s: SYNC offline for transport\n", t->serial);
284    p = get_apacket();
285    p->msg.command = A_SYNC;
286    p->msg.arg0 = 0;
287    p->msg.arg1 = 0;
288    p->msg.magic = A_SYNC ^ 0xffffffff;
289    if(write_packet(t->fd, t->serial, &p)) {
290        put_apacket(p);
291        D("%s: failed to write SYNC apacket to transport", t->serial);
292    }
293
294oops:
295    D("%s: transport output thread is exiting\n", t->serial);
296    kick_transport(t);
297    transport_unref(t);
298    return 0;
299}
300
301static void *input_thread(void *_t)
302{
303    atransport *t = reinterpret_cast<atransport*>(_t);
304    apacket *p;
305    int active = 0;
306
307    D("%s: starting transport input thread, reading from fd %d\n",
308       t->serial, t->fd);
309
310    for(;;){
311        if(read_packet(t->fd, t->serial, &p)) {
312            D("%s: failed to read apacket from transport on fd %d\n",
313               t->serial, t->fd );
314            break;
315        }
316        if(p->msg.command == A_SYNC){
317            if(p->msg.arg0 == 0) {
318                D("%s: transport SYNC offline\n", t->serial);
319                put_apacket(p);
320                break;
321            } else {
322                if(p->msg.arg1 == t->sync_token) {
323                    D("%s: transport SYNC online\n", t->serial);
324                    active = 1;
325                } else {
326                    D("%s: transport ignoring SYNC %d != %d\n",
327                      t->serial, p->msg.arg1, t->sync_token);
328                }
329            }
330        } else {
331            if(active) {
332                D("%s: transport got packet, sending to remote\n", t->serial);
333                t->write_to_remote(p, t);
334            } else {
335                D("%s: transport ignoring packet while offline\n", t->serial);
336            }
337        }
338
339        put_apacket(p);
340    }
341
342    // this is necessary to avoid a race condition that occured when a transport closes
343    // while a client socket is still active.
344    close_all_sockets(t);
345
346    D("%s: transport input thread is exiting, fd %d\n", t->serial, t->fd);
347    kick_transport(t);
348    transport_unref(t);
349    return 0;
350}
351
352
353static int transport_registration_send = -1;
354static int transport_registration_recv = -1;
355static fdevent transport_registration_fde;
356
357
358#if ADB_HOST
359
360/* this adds support required by the 'track-devices' service.
361 * this is used to send the content of "list_transport" to any
362 * number of client connections that want it through a single
363 * live TCP connection
364 */
365struct device_tracker {
366    asocket          socket;
367    int              update_needed;
368    device_tracker*  next;
369};
370
371/* linked list of all device trackers */
372static device_tracker*   device_tracker_list;
373
374static void
375device_tracker_remove( device_tracker*  tracker )
376{
377    device_tracker**  pnode = &device_tracker_list;
378    device_tracker*   node  = *pnode;
379
380    adb_mutex_lock( &transport_lock );
381    while (node) {
382        if (node == tracker) {
383            *pnode = node->next;
384            break;
385        }
386        pnode = &node->next;
387        node  = *pnode;
388    }
389    adb_mutex_unlock( &transport_lock );
390}
391
392static void
393device_tracker_close( asocket*  socket )
394{
395    device_tracker*  tracker = (device_tracker*) socket;
396    asocket*         peer    = socket->peer;
397
398    D( "device tracker %p removed\n", tracker);
399    if (peer) {
400        peer->peer = NULL;
401        peer->close(peer);
402    }
403    device_tracker_remove(tracker);
404    free(tracker);
405}
406
407static int
408device_tracker_enqueue( asocket*  socket, apacket*  p )
409{
410    /* you can't read from a device tracker, close immediately */
411    put_apacket(p);
412    device_tracker_close(socket);
413    return -1;
414}
415
416static int device_tracker_send(device_tracker* tracker, const std::string& string) {
417    apacket* p = get_apacket();
418    asocket* peer = tracker->socket.peer;
419
420    snprintf(reinterpret_cast<char*>(p->data), 5, "%04x", static_cast<int>(string.size()));
421    memcpy(&p->data[4], string.data(), string.size());
422    p->len = 4 + string.size();
423    return peer->enqueue(peer, p);
424}
425
426static void device_tracker_ready(asocket* socket) {
427    device_tracker* tracker = reinterpret_cast<device_tracker*>(socket);
428
429    // We want to send the device list when the tracker connects
430    // for the first time, even if no update occurred.
431    if (tracker->update_needed > 0) {
432        tracker->update_needed = 0;
433
434        std::string transports = list_transports(false);
435        device_tracker_send(tracker, transports);
436    }
437}
438
439asocket*
440create_device_tracker(void)
441{
442    device_tracker* tracker = reinterpret_cast<device_tracker*>(calloc(1, sizeof(*tracker)));
443    if (tracker == nullptr) fatal("cannot allocate device tracker");
444
445    D( "device tracker %p created\n", tracker);
446
447    tracker->socket.enqueue = device_tracker_enqueue;
448    tracker->socket.ready   = device_tracker_ready;
449    tracker->socket.close   = device_tracker_close;
450    tracker->update_needed  = 1;
451
452    tracker->next       = device_tracker_list;
453    device_tracker_list = tracker;
454
455    return &tracker->socket;
456}
457
458
459// Call this function each time the transport list has changed.
460void update_transports() {
461    std::string transports = list_transports(false);
462
463    device_tracker* tracker = device_tracker_list;
464    while (tracker != nullptr) {
465        device_tracker* next = tracker->next;
466        // This may destroy the tracker if the connection is closed.
467        device_tracker_send(tracker, transports);
468        tracker = next;
469    }
470}
471
472#else
473
474void update_transports() {
475    // Nothing to do on the device side.
476}
477
478#endif // ADB_HOST
479
480struct tmsg
481{
482    atransport *transport;
483    int         action;
484};
485
486static int
487transport_read_action(int  fd, struct tmsg*  m)
488{
489    char *p   = (char*)m;
490    int   len = sizeof(*m);
491    int   r;
492
493    while(len > 0) {
494        r = adb_read(fd, p, len);
495        if(r > 0) {
496            len -= r;
497            p   += r;
498        } else {
499            if((r < 0) && (errno == EINTR)) continue;
500            D("transport_read_action: on fd %d, error %d: %s\n",
501              fd, errno, strerror(errno));
502            return -1;
503        }
504    }
505    return 0;
506}
507
508static int
509transport_write_action(int  fd, struct tmsg*  m)
510{
511    char *p   = (char*)m;
512    int   len = sizeof(*m);
513    int   r;
514
515    while(len > 0) {
516        r = adb_write(fd, p, len);
517        if(r > 0) {
518            len -= r;
519            p   += r;
520        } else {
521            if((r < 0) && (errno == EINTR)) continue;
522            D("transport_write_action: on fd %d, error %d: %s\n",
523              fd, errno, strerror(errno));
524            return -1;
525        }
526    }
527    return 0;
528}
529
530static void transport_registration_func(int _fd, unsigned ev, void *data)
531{
532    tmsg m;
533    int s[2];
534    atransport *t;
535
536    if(!(ev & FDE_READ)) {
537        return;
538    }
539
540    if(transport_read_action(_fd, &m)) {
541        fatal_errno("cannot read transport registration socket");
542    }
543
544    t = m.transport;
545
546    if(m.action == 0){
547        D("transport: %s removing and free'ing %d\n", t->serial, t->transport_socket);
548
549            /* IMPORTANT: the remove closes one half of the
550            ** socket pair.  The close closes the other half.
551            */
552        fdevent_remove(&(t->transport_fde));
553        adb_close(t->fd);
554
555        adb_mutex_lock(&transport_lock);
556        t->next->prev = t->prev;
557        t->prev->next = t->next;
558        adb_mutex_unlock(&transport_lock);
559
560        run_transport_disconnects(t);
561
562        if (t->product)
563            free(t->product);
564        if (t->serial)
565            free(t->serial);
566        if (t->model)
567            free(t->model);
568        if (t->device)
569            free(t->device);
570        if (t->devpath)
571            free(t->devpath);
572
573        memset(t,0xee,sizeof(atransport));
574        free(t);
575
576        update_transports();
577        return;
578    }
579
580    /* don't create transport threads for inaccessible devices */
581    if (t->connection_state != kCsNoPerm) {
582        /* initial references are the two threads */
583        t->ref_count = 2;
584
585        if(adb_socketpair(s)) {
586            fatal_errno("cannot open transport socketpair");
587        }
588
589        D("transport: %s socketpair: (%d,%d) starting", t->serial, s[0], s[1]);
590
591        t->transport_socket = s[0];
592        t->fd = s[1];
593
594        fdevent_install(&(t->transport_fde),
595                        t->transport_socket,
596                        transport_socket_events,
597                        t);
598
599        fdevent_set(&(t->transport_fde), FDE_READ);
600
601        if (!adb_thread_create(input_thread, t)) {
602            fatal_errno("cannot create input thread");
603        }
604
605        if (!adb_thread_create(output_thread, t)) {
606            fatal_errno("cannot create output thread");
607        }
608    }
609
610    adb_mutex_lock(&transport_lock);
611    /* remove from pending list */
612    t->next->prev = t->prev;
613    t->prev->next = t->next;
614    /* put us on the master device list */
615    t->next = &transport_list;
616    t->prev = transport_list.prev;
617    t->next->prev = t;
618    t->prev->next = t;
619    adb_mutex_unlock(&transport_lock);
620
621    t->disconnects.next = t->disconnects.prev = &t->disconnects;
622
623    update_transports();
624}
625
626void init_transport_registration(void)
627{
628    int s[2];
629
630    if(adb_socketpair(s)){
631        fatal_errno("cannot open transport registration socketpair");
632    }
633    D("socketpair: (%d,%d)", s[0], s[1]);
634
635    transport_registration_send = s[0];
636    transport_registration_recv = s[1];
637
638    fdevent_install(&transport_registration_fde,
639                    transport_registration_recv,
640                    transport_registration_func,
641                    0);
642
643    fdevent_set(&transport_registration_fde, FDE_READ);
644}
645
646/* the fdevent select pump is single threaded */
647static void register_transport(atransport *transport)
648{
649    tmsg m;
650    m.transport = transport;
651    m.action = 1;
652    D("transport: %s registered\n", transport->serial);
653    if(transport_write_action(transport_registration_send, &m)) {
654        fatal_errno("cannot write transport registration socket\n");
655    }
656}
657
658static void remove_transport(atransport *transport)
659{
660    tmsg m;
661    m.transport = transport;
662    m.action = 0;
663    D("transport: %s removed\n", transport->serial);
664    if(transport_write_action(transport_registration_send, &m)) {
665        fatal_errno("cannot write transport registration socket\n");
666    }
667}
668
669
670static void transport_unref_locked(atransport *t)
671{
672    t->ref_count--;
673    if (t->ref_count == 0) {
674        D("transport: %s unref (kicking and closing)\n", t->serial);
675        if (!t->kicked) {
676            t->kicked = 1;
677            t->kick(t);
678        }
679        t->close(t);
680        remove_transport(t);
681    } else {
682        D("transport: %s unref (count=%d)\n", t->serial, t->ref_count);
683    }
684}
685
686static void transport_unref(atransport *t)
687{
688    if (t) {
689        adb_mutex_lock(&transport_lock);
690        transport_unref_locked(t);
691        adb_mutex_unlock(&transport_lock);
692    }
693}
694
695void add_transport_disconnect(atransport*  t, adisconnect*  dis)
696{
697    adb_mutex_lock(&transport_lock);
698    dis->next       = &t->disconnects;
699    dis->prev       = dis->next->prev;
700    dis->prev->next = dis;
701    dis->next->prev = dis;
702    adb_mutex_unlock(&transport_lock);
703}
704
705void remove_transport_disconnect(atransport*  t, adisconnect*  dis)
706{
707    dis->prev->next = dis->next;
708    dis->next->prev = dis->prev;
709    dis->next = dis->prev = dis;
710}
711
712static int qual_match(const char *to_test,
713                      const char *prefix, const char *qual, bool sanitize_qual)
714{
715    if (!to_test || !*to_test)
716        /* Return true if both the qual and to_test are null strings. */
717        return !qual || !*qual;
718
719    if (!qual)
720        return 0;
721
722    if (prefix) {
723        while (*prefix) {
724            if (*prefix++ != *to_test++)
725                return 0;
726        }
727    }
728
729    while (*qual) {
730        char ch = *qual++;
731        if (sanitize_qual && !isalnum(ch))
732            ch = '_';
733        if (ch != *to_test++)
734            return 0;
735    }
736
737    /* Everything matched so far.  Return true if *to_test is a NUL. */
738    return !*to_test;
739}
740
741atransport* acquire_one_transport(ConnectionState state, TransportType type,
742                                  const char* serial, std::string* error_out) {
743    atransport *t;
744    atransport *result = NULL;
745    int ambiguous = 0;
746
747retry:
748    if (error_out) *error_out = android::base::StringPrintf("device '%s' not found", serial);
749
750    adb_mutex_lock(&transport_lock);
751    for (t = transport_list.next; t != &transport_list; t = t->next) {
752        if (t->connection_state == kCsNoPerm) {
753            if (error_out) *error_out = "insufficient permissions for device";
754            continue;
755        }
756
757        /* check for matching serial number */
758        if (serial) {
759            if ((t->serial && !strcmp(serial, t->serial)) ||
760                (t->devpath && !strcmp(serial, t->devpath)) ||
761                qual_match(serial, "product:", t->product, false) ||
762                qual_match(serial, "model:", t->model, true) ||
763                qual_match(serial, "device:", t->device, false)) {
764                if (result) {
765                    if (error_out) *error_out = "more than one device";
766                    ambiguous = 1;
767                    result = NULL;
768                    break;
769                }
770                result = t;
771            }
772        } else {
773            if (type == kTransportUsb && t->type == kTransportUsb) {
774                if (result) {
775                    if (error_out) *error_out = "more than one device";
776                    ambiguous = 1;
777                    result = NULL;
778                    break;
779                }
780                result = t;
781            } else if (type == kTransportLocal && t->type == kTransportLocal) {
782                if (result) {
783                    if (error_out) *error_out = "more than one emulator";
784                    ambiguous = 1;
785                    result = NULL;
786                    break;
787                }
788                result = t;
789            } else if (type == kTransportAny) {
790                if (result) {
791                    if (error_out) *error_out = "more than one device/emulator";
792                    ambiguous = 1;
793                    result = NULL;
794                    break;
795                }
796                result = t;
797            }
798        }
799    }
800    adb_mutex_unlock(&transport_lock);
801
802    if (result) {
803        if (result->connection_state == kCsUnauthorized) {
804            if (error_out) {
805                *error_out = "device unauthorized.\n";
806                char* ADB_VENDOR_KEYS = getenv("ADB_VENDOR_KEYS");
807                *error_out += "This adbd's $ADB_VENDOR_KEYS is ";
808                *error_out += ADB_VENDOR_KEYS ? ADB_VENDOR_KEYS : "not set";
809                *error_out += "; try 'adb kill-server' if that seems wrong.\n";
810                *error_out += "Otherwise check for a confirmation dialog on your device.";
811            }
812            result = NULL;
813        }
814
815        /* offline devices are ignored -- they are either being born or dying */
816        if (result && result->connection_state == kCsOffline) {
817            if (error_out) *error_out = "device offline";
818            result = NULL;
819        }
820
821        /* check for required connection state */
822        if (result && state != kCsAny && result->connection_state != state) {
823            if (error_out) *error_out = "invalid device state";
824            result = NULL;
825        }
826    }
827
828    if (result) {
829        /* found one that we can take */
830        if (error_out) *error_out = "success";
831    } else if (state != kCsAny && (serial || !ambiguous)) {
832        adb_sleep_ms(1000);
833        goto retry;
834    }
835
836    return result;
837}
838
839const char* atransport::connection_state_name() const {
840    switch (connection_state) {
841    case kCsOffline: return "offline";
842    case kCsBootloader: return "bootloader";
843    case kCsDevice: return "device";
844    case kCsHost: return "host";
845    case kCsRecovery: return "recovery";
846    case kCsNoPerm: return "no permissions";
847    case kCsSideload: return "sideload";
848    case kCsUnauthorized: return "unauthorized";
849    default: return "unknown";
850    }
851}
852
853#if ADB_HOST
854
855static void append_transport_info(std::string* result, const char* key,
856                                  const char* value, bool sanitize) {
857    if (value == nullptr || *value == '\0') {
858        return;
859    }
860
861    *result += ' ';
862    *result += key;
863
864    for (const char* p = value; *p; ++p) {
865        result->push_back((!sanitize || isalnum(*p)) ? *p : '_');
866    }
867}
868
869static void append_transport(atransport* t, std::string* result, bool long_listing) {
870    const char* serial = t->serial;
871    if (!serial || !serial[0]) {
872        serial = "(no serial number)";
873    }
874
875    if (!long_listing) {
876        *result += serial;
877        *result += '\t';
878        *result += t->connection_state_name();
879    } else {
880        android::base::StringAppendF(result, "%-22s %s", serial, t->connection_state_name());
881
882        append_transport_info(result, "", t->devpath, false);
883        append_transport_info(result, "product:", t->product, false);
884        append_transport_info(result, "model:", t->model, true);
885        append_transport_info(result, "device:", t->device, false);
886    }
887    *result += '\n';
888}
889
890std::string list_transports(bool long_listing) {
891    std::string result;
892    adb_mutex_lock(&transport_lock);
893    for (atransport* t = transport_list.next; t != &transport_list; t = t->next) {
894        append_transport(t, &result, long_listing);
895    }
896    adb_mutex_unlock(&transport_lock);
897    return result;
898}
899
900/* hack for osx */
901void close_usb_devices()
902{
903    adb_mutex_lock(&transport_lock);
904    for (atransport* t = transport_list.next; t != &transport_list; t = t->next) {
905        if ( !t->kicked ) {
906            t->kicked = 1;
907            t->kick(t);
908        }
909    }
910    adb_mutex_unlock(&transport_lock);
911}
912#endif // ADB_HOST
913
914int register_socket_transport(int s, const char *serial, int port, int local)
915{
916    atransport *t = reinterpret_cast<atransport*>(calloc(1, sizeof(atransport)));
917    if (t == nullptr) {
918        return -1;
919    }
920
921    atransport *n;
922    char buff[32];
923
924    if (!serial) {
925        snprintf(buff, sizeof buff, "T-%p", t);
926        serial = buff;
927    }
928    D("transport: %s init'ing for socket %d, on port %d\n", serial, s, port);
929    if (init_socket_transport(t, s, port, local) < 0) {
930        free(t);
931        return -1;
932    }
933
934    adb_mutex_lock(&transport_lock);
935    for (n = pending_list.next; n != &pending_list; n = n->next) {
936        if (n->serial && !strcmp(serial, n->serial)) {
937            adb_mutex_unlock(&transport_lock);
938            free(t);
939            return -1;
940        }
941    }
942
943    for (n = transport_list.next; n != &transport_list; n = n->next) {
944        if (n->serial && !strcmp(serial, n->serial)) {
945            adb_mutex_unlock(&transport_lock);
946            free(t);
947            return -1;
948        }
949    }
950
951    t->next = &pending_list;
952    t->prev = pending_list.prev;
953    t->next->prev = t;
954    t->prev->next = t;
955    t->serial = strdup(serial);
956    adb_mutex_unlock(&transport_lock);
957
958    register_transport(t);
959    return 0;
960}
961
962#if ADB_HOST
963atransport *find_transport(const char *serial)
964{
965    atransport *t;
966
967    adb_mutex_lock(&transport_lock);
968    for(t = transport_list.next; t != &transport_list; t = t->next) {
969        if (t->serial && !strcmp(serial, t->serial)) {
970            break;
971        }
972     }
973    adb_mutex_unlock(&transport_lock);
974
975    if (t != &transport_list)
976        return t;
977    else
978        return 0;
979}
980
981void unregister_transport(atransport *t)
982{
983    adb_mutex_lock(&transport_lock);
984    t->next->prev = t->prev;
985    t->prev->next = t->next;
986    adb_mutex_unlock(&transport_lock);
987
988    kick_transport(t);
989    transport_unref(t);
990}
991
992// unregisters all non-emulator TCP transports
993void unregister_all_tcp_transports()
994{
995    atransport *t, *next;
996    adb_mutex_lock(&transport_lock);
997    for (t = transport_list.next; t != &transport_list; t = next) {
998        next = t->next;
999        if (t->type == kTransportLocal && t->adb_port == 0) {
1000            t->next->prev = t->prev;
1001            t->prev->next = next;
1002            // we cannot call kick_transport when holding transport_lock
1003            if (!t->kicked)
1004            {
1005                t->kicked = 1;
1006                t->kick(t);
1007            }
1008            transport_unref_locked(t);
1009        }
1010     }
1011
1012    adb_mutex_unlock(&transport_lock);
1013}
1014
1015#endif
1016
1017void register_usb_transport(usb_handle *usb, const char *serial, const char *devpath, unsigned writeable)
1018{
1019    atransport *t = reinterpret_cast<atransport*>(calloc(1, sizeof(atransport)));
1020    if (t == nullptr) fatal("cannot allocate USB atransport");
1021    D("transport: %p init'ing for usb_handle %p (sn='%s')\n", t, usb,
1022      serial ? serial : "");
1023    init_usb_transport(t, usb, (writeable ? kCsOffline : kCsNoPerm));
1024    if(serial) {
1025        t->serial = strdup(serial);
1026    }
1027    if(devpath) {
1028        t->devpath = strdup(devpath);
1029    }
1030
1031    adb_mutex_lock(&transport_lock);
1032    t->next = &pending_list;
1033    t->prev = pending_list.prev;
1034    t->next->prev = t;
1035    t->prev->next = t;
1036    adb_mutex_unlock(&transport_lock);
1037
1038    register_transport(t);
1039}
1040
1041// This should only be used for transports with connection_state == kCsNoPerm.
1042void unregister_usb_transport(usb_handle* usb) {
1043    adb_mutex_lock(&transport_lock);
1044    for (atransport* t = transport_list.next; t != &transport_list;
1045         t = t->next) {
1046        if (t->usb == usb && t->connection_state == kCsNoPerm) {
1047            t->next->prev = t->prev;
1048            t->prev->next = t->next;
1049            break;
1050        }
1051    }
1052    adb_mutex_unlock(&transport_lock);
1053}
1054
1055#undef TRACE_TAG
1056#define TRACE_TAG  TRACE_RWX
1057
1058int check_header(apacket *p)
1059{
1060    if(p->msg.magic != (p->msg.command ^ 0xffffffff)) {
1061        D("check_header(): invalid magic\n");
1062        return -1;
1063    }
1064
1065    if(p->msg.data_length > MAX_PAYLOAD) {
1066        D("check_header(): %d > MAX_PAYLOAD\n", p->msg.data_length);
1067        return -1;
1068    }
1069
1070    return 0;
1071}
1072
1073int check_data(apacket *p)
1074{
1075    unsigned count, sum;
1076    unsigned char *x;
1077
1078    count = p->msg.data_length;
1079    x = p->data;
1080    sum = 0;
1081    while(count-- > 0) {
1082        sum += *x++;
1083    }
1084
1085    if(sum != p->msg.data_check) {
1086        return -1;
1087    } else {
1088        return 0;
1089    }
1090}
1091