support "sideload over ADB" mode

Rather than depending on the existence of some place to store a file
that is accessible to users on an an unbootable device (eg, a physical
sdcard, external USB drive, etc.), add support for sideloading
packages sent to the device with adb.

This change adds a "minimal adbd" which supports nothing but receiving
a package over adb (with the "adb sideload" command) and storing it to
a fixed filename in the /tmp ramdisk, from where it can be verified
and sideloaded in the usual way.  This should be leave available even
on locked user-build devices.

The user can select "apply package from ADB" from the recovery menu,
which starts minimal-adb mode (shutting down any real adbd that may be
running).  Once minimal-adb has received a package it exits
(restarting real adbd if appropriate) and then verification and
installation of the received package proceeds.

Change-Id: I6fe13161ca064a98d06fa32104e1f432826582f5
diff --git a/minadbd/sockets.c b/minadbd/sockets.c
new file mode 100644
index 0000000..9f4cecb
--- /dev/null
+++ b/minadbd/sockets.c
@@ -0,0 +1,830 @@
+/*
+ * 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.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <ctype.h>
+
+#include "sysdeps.h"
+
+#define  TRACE_TAG  TRACE_SOCKETS
+#include "adb.h"
+
+ADB_MUTEX_DEFINE( socket_list_lock );
+
+static void local_socket_close_locked(asocket *s);
+
+int sendfailmsg(int fd, const char *reason)
+{
+    char buf[9];
+    int len;
+    len = strlen(reason);
+    if(len > 0xffff) len = 0xffff;
+    snprintf(buf, sizeof buf, "FAIL%04x", len);
+    if(writex(fd, buf, 8)) return -1;
+    return writex(fd, reason, len);
+}
+
+//extern int online;
+
+static unsigned local_socket_next_id = 1;
+
+static asocket local_socket_list = {
+    .next = &local_socket_list,
+    .prev = &local_socket_list,
+};
+
+/* the the list of currently closing local sockets.
+** these have no peer anymore, but still packets to
+** write to their fd.
+*/
+static asocket local_socket_closing_list = {
+    .next = &local_socket_closing_list,
+    .prev = &local_socket_closing_list,
+};
+
+asocket *find_local_socket(unsigned id)
+{
+    asocket *s;
+    asocket *result = NULL;
+
+    adb_mutex_lock(&socket_list_lock);
+    for (s = local_socket_list.next; s != &local_socket_list; s = s->next) {
+        if (s->id == id) {
+            result = s;
+            break;
+        }
+    }
+    adb_mutex_unlock(&socket_list_lock);
+
+    return result;
+}
+
+static void
+insert_local_socket(asocket*  s, asocket*  list)
+{
+    s->next       = list;
+    s->prev       = s->next->prev;
+    s->prev->next = s;
+    s->next->prev = s;
+}
+
+
+void install_local_socket(asocket *s)
+{
+    adb_mutex_lock(&socket_list_lock);
+
+    s->id = local_socket_next_id++;
+    insert_local_socket(s, &local_socket_list);
+
+    adb_mutex_unlock(&socket_list_lock);
+}
+
+void remove_socket(asocket *s)
+{
+    // socket_list_lock should already be held
+    if (s->prev && s->next)
+    {
+        s->prev->next = s->next;
+        s->next->prev = s->prev;
+        s->next = 0;
+        s->prev = 0;
+        s->id = 0;
+    }
+}
+
+void close_all_sockets(atransport *t)
+{
+    asocket *s;
+
+        /* this is a little gross, but since s->close() *will* modify
+        ** the list out from under you, your options are limited.
+        */
+    adb_mutex_lock(&socket_list_lock);
+restart:
+    for(s = local_socket_list.next; s != &local_socket_list; s = s->next){
+        if(s->transport == t || (s->peer && s->peer->transport == t)) {
+            local_socket_close_locked(s);
+            goto restart;
+        }
+    }
+    adb_mutex_unlock(&socket_list_lock);
+}
+
+static int local_socket_enqueue(asocket *s, apacket *p)
+{
+    D("LS(%d): enqueue %d\n", s->id, p->len);
+
+    p->ptr = p->data;
+
+        /* if there is already data queue'd, we will receive
+        ** events when it's time to write.  just add this to
+        ** the tail
+        */
+    if(s->pkt_first) {
+        goto enqueue;
+    }
+
+        /* write as much as we can, until we
+        ** would block or there is an error/eof
+        */
+    while(p->len > 0) {
+        int r = adb_write(s->fd, p->ptr, p->len);
+        if(r > 0) {
+            p->len -= r;
+            p->ptr += r;
+            continue;
+        }
+        if((r == 0) || (errno != EAGAIN)) {
+            D( "LS(%d): not ready, errno=%d: %s\n", s->id, errno, strerror(errno) );
+            s->close(s);
+            return 1; /* not ready (error) */
+        } else {
+            break;
+        }
+    }
+
+    if(p->len == 0) {
+        put_apacket(p);
+        return 0; /* ready for more data */
+    }
+
+enqueue:
+    p->next = 0;
+    if(s->pkt_first) {
+        s->pkt_last->next = p;
+    } else {
+        s->pkt_first = p;
+    }
+    s->pkt_last = p;
+
+        /* make sure we are notified when we can drain the queue */
+    fdevent_add(&s->fde, FDE_WRITE);
+
+    return 1; /* not ready (backlog) */
+}
+
+static void local_socket_ready(asocket *s)
+{
+        /* far side is ready for data, pay attention to
+           readable events */
+    fdevent_add(&s->fde, FDE_READ);
+//    D("LS(%d): ready()\n", s->id);
+}
+
+static void local_socket_close(asocket *s)
+{
+    adb_mutex_lock(&socket_list_lock);
+    local_socket_close_locked(s);
+    adb_mutex_unlock(&socket_list_lock);
+}
+
+// be sure to hold the socket list lock when calling this
+static void local_socket_destroy(asocket  *s)
+{
+    apacket *p, *n;
+    D("LS(%d): destroying fde.fd=%d\n", s->id, s->fde.fd);
+
+        /* IMPORTANT: the remove closes the fd
+        ** that belongs to this socket
+        */
+    fdevent_remove(&s->fde);
+
+        /* dispose of any unwritten data */
+    for(p = s->pkt_first; p; p = n) {
+        D("LS(%d): discarding %d bytes\n", s->id, p->len);
+        n = p->next;
+        put_apacket(p);
+    }
+    remove_socket(s);
+    free(s);
+}
+
+
+static void local_socket_close_locked(asocket *s)
+{
+    D("entered. LS(%d) fd=%d\n", s->id, s->fd);
+    if(s->peer) {
+        D("LS(%d): closing peer. peer->id=%d peer->fd=%d\n",
+          s->id, s->peer->id, s->peer->fd);
+        s->peer->peer = 0;
+        // tweak to avoid deadlock
+        if (s->peer->close == local_socket_close) {
+            local_socket_close_locked(s->peer);
+        } else {
+            s->peer->close(s->peer);
+        }
+        s->peer = 0;
+    }
+
+        /* If we are already closing, or if there are no
+        ** pending packets, destroy immediately
+        */
+    if (s->closing || s->pkt_first == NULL) {
+        int   id = s->id;
+        local_socket_destroy(s);
+        D("LS(%d): closed\n", id);
+        return;
+    }
+
+        /* otherwise, put on the closing list
+        */
+    D("LS(%d): closing\n", s->id);
+    s->closing = 1;
+    fdevent_del(&s->fde, FDE_READ);
+    remove_socket(s);
+    D("LS(%d): put on socket_closing_list fd=%d\n", s->id, s->fd);
+    insert_local_socket(s, &local_socket_closing_list);
+}
+
+static void local_socket_event_func(int fd, unsigned ev, void *_s)
+{
+    asocket *s = _s;
+
+    D("LS(%d): event_func(fd=%d(==%d), ev=%04x)\n", s->id, s->fd, fd, ev);
+
+    /* put the FDE_WRITE processing before the FDE_READ
+    ** in order to simplify the code.
+    */
+    if(ev & FDE_WRITE){
+        apacket *p;
+
+        while((p = s->pkt_first) != 0) {
+            while(p->len > 0) {
+                int r = adb_write(fd, p->ptr, p->len);
+                if(r > 0) {
+                    p->ptr += r;
+                    p->len -= r;
+                    continue;
+                }
+                if(r < 0) {
+                    /* returning here is ok because FDE_READ will
+                    ** be processed in the next iteration loop
+                    */
+                    if(errno == EAGAIN) return;
+                    if(errno == EINTR) continue;
+                }
+                D(" closing after write because r=%d and errno is %d\n", r, errno);
+                s->close(s);
+                return;
+            }
+
+            if(p->len == 0) {
+                s->pkt_first = p->next;
+                if(s->pkt_first == 0) s->pkt_last = 0;
+                put_apacket(p);
+            }
+        }
+
+            /* if we sent the last packet of a closing socket,
+            ** we can now destroy it.
+            */
+        if (s->closing) {
+            D(" closing because 'closing' is set after write\n");
+            s->close(s);
+            return;
+        }
+
+            /* no more packets queued, so we can ignore
+            ** writable events again and tell our peer
+            ** to resume writing
+            */
+        fdevent_del(&s->fde, FDE_WRITE);
+        s->peer->ready(s->peer);
+    }
+
+
+    if(ev & FDE_READ){
+        apacket *p = get_apacket();
+        unsigned char *x = p->data;
+        size_t avail = MAX_PAYLOAD;
+        int r;
+        int is_eof = 0;
+
+        while(avail > 0) {
+            r = adb_read(fd, x, avail);
+            D("LS(%d): post adb_read(fd=%d,...) r=%d (errno=%d) avail=%d\n", s->id, s->fd, r, r<0?errno:0, avail);
+            if(r > 0) {
+                avail -= r;
+                x += r;
+                continue;
+            }
+            if(r < 0) {
+                if(errno == EAGAIN) break;
+                if(errno == EINTR) continue;
+            }
+
+                /* r = 0 or unhandled error */
+            is_eof = 1;
+            break;
+        }
+        D("LS(%d): fd=%d post avail loop. r=%d is_eof=%d forced_eof=%d\n",
+          s->id, s->fd, r, is_eof, s->fde.force_eof);
+        if((avail == MAX_PAYLOAD) || (s->peer == 0)) {
+            put_apacket(p);
+        } else {
+            p->len = MAX_PAYLOAD - avail;
+
+            r = s->peer->enqueue(s->peer, p);
+            D("LS(%d): fd=%d post peer->enqueue(). r=%d\n", s->id, s->fd, r);
+
+            if(r < 0) {
+                    /* error return means they closed us as a side-effect
+                    ** and we must return immediately.
+                    **
+                    ** note that if we still have buffered packets, the
+                    ** socket will be placed on the closing socket list.
+                    ** this handler function will be called again
+                    ** to process FDE_WRITE events.
+                    */
+                return;
+            }
+
+            if(r > 0) {
+                    /* if the remote cannot accept further events,
+                    ** we disable notification of READs.  They'll
+                    ** be enabled again when we get a call to ready()
+                    */
+                fdevent_del(&s->fde, FDE_READ);
+            }
+        }
+        /* Don't allow a forced eof if data is still there */
+        if((s->fde.force_eof && !r) || is_eof) {
+            D(" closing because is_eof=%d r=%d s->fde.force_eof=%d\n", is_eof, r, s->fde.force_eof);
+            s->close(s);
+        }
+    }
+
+    if(ev & FDE_ERROR){
+            /* this should be caught be the next read or write
+            ** catching it here means we may skip the last few
+            ** bytes of readable data.
+            */
+//        s->close(s);
+        D("LS(%d): FDE_ERROR (fd=%d)\n", s->id, s->fd);
+
+        return;
+    }
+}
+
+asocket *create_local_socket(int fd)
+{
+    asocket *s = calloc(1, sizeof(asocket));
+    if (s == NULL) fatal("cannot allocate socket");
+    s->fd = fd;
+    s->enqueue = local_socket_enqueue;
+    s->ready = local_socket_ready;
+    s->close = local_socket_close;
+    install_local_socket(s);
+
+    fdevent_install(&s->fde, fd, local_socket_event_func, s);
+/*    fdevent_add(&s->fde, FDE_ERROR); */
+    //fprintf(stderr, "Created local socket in create_local_socket \n");
+    D("LS(%d): created (fd=%d)\n", s->id, s->fd);
+    return s;
+}
+
+asocket *create_local_service_socket(const char *name)
+{
+    asocket *s;
+    int fd;
+
+    fd = service_to_fd(name);
+    if(fd < 0) return 0;
+
+    s = create_local_socket(fd);
+    D("LS(%d): bound to '%s' via %d\n", s->id, name, fd);
+    return s;
+}
+
+#if ADB_HOST
+static asocket *create_host_service_socket(const char *name, const char* serial)
+{
+    asocket *s;
+
+    s = host_service_to_socket(name, serial);
+
+    if (s != NULL) {
+        D("LS(%d) bound to '%s'\n", s->id, name);
+        return s;
+    }
+
+    return s;
+}
+#endif /* ADB_HOST */
+
+/* a Remote socket is used to send/receive data to/from a given transport object
+** it needs to be closed when the transport is forcibly destroyed by the user
+*/
+typedef struct aremotesocket {
+    asocket      socket;
+    adisconnect  disconnect;
+} aremotesocket;
+
+static int remote_socket_enqueue(asocket *s, apacket *p)
+{
+    D("entered remote_socket_enqueue RS(%d) WRITE fd=%d peer.fd=%d\n",
+      s->id, s->fd, s->peer->fd);
+    p->msg.command = A_WRTE;
+    p->msg.arg0 = s->peer->id;
+    p->msg.arg1 = s->id;
+    p->msg.data_length = p->len;
+    send_packet(p, s->transport);
+    return 1;
+}
+
+static void remote_socket_ready(asocket *s)
+{
+    D("entered remote_socket_ready RS(%d) OKAY fd=%d peer.fd=%d\n",
+      s->id, s->fd, s->peer->fd);
+    apacket *p = get_apacket();
+    p->msg.command = A_OKAY;
+    p->msg.arg0 = s->peer->id;
+    p->msg.arg1 = s->id;
+    send_packet(p, s->transport);
+}
+
+static void remote_socket_close(asocket *s)
+{
+    D("entered remote_socket_close RS(%d) CLOSE fd=%d peer->fd=%d\n",
+      s->id, s->fd, s->peer?s->peer->fd:-1);
+    apacket *p = get_apacket();
+    p->msg.command = A_CLSE;
+    if(s->peer) {
+        p->msg.arg0 = s->peer->id;
+        s->peer->peer = 0;
+        D("RS(%d) peer->close()ing peer->id=%d peer->fd=%d\n",
+          s->id, s->peer->id, s->peer->fd);
+        s->peer->close(s->peer);
+    }
+    p->msg.arg1 = s->id;
+    send_packet(p, s->transport);
+    D("RS(%d): closed\n", s->id);
+    remove_transport_disconnect( s->transport, &((aremotesocket*)s)->disconnect );
+    free(s);
+}
+
+static void remote_socket_disconnect(void*  _s, atransport*  t)
+{
+    asocket*  s    = _s;
+    asocket*  peer = s->peer;
+
+    D("remote_socket_disconnect RS(%d)\n", s->id);
+    if (peer) {
+        peer->peer = NULL;
+        peer->close(peer);
+    }
+    remove_transport_disconnect( s->transport, &((aremotesocket*)s)->disconnect );
+    free(s);
+}
+
+asocket *create_remote_socket(unsigned id, atransport *t)
+{
+    asocket *s = calloc(1, sizeof(aremotesocket));
+    adisconnect*  dis = &((aremotesocket*)s)->disconnect;
+
+    if (s == NULL) fatal("cannot allocate socket");
+    s->id = id;
+    s->enqueue = remote_socket_enqueue;
+    s->ready = remote_socket_ready;
+    s->close = remote_socket_close;
+    s->transport = t;
+
+    dis->func   = remote_socket_disconnect;
+    dis->opaque = s;
+    add_transport_disconnect( t, dis );
+    D("RS(%d): created\n", s->id);
+    return s;
+}
+
+void connect_to_remote(asocket *s, const char *destination)
+{
+    D("Connect_to_remote call RS(%d) fd=%d\n", s->id, s->fd);
+    apacket *p = get_apacket();
+    int len = strlen(destination) + 1;
+
+    if(len > (MAX_PAYLOAD-1)) {
+        fatal("destination oversized");
+    }
+
+    D("LS(%d): connect('%s')\n", s->id, destination);
+    p->msg.command = A_OPEN;
+    p->msg.arg0 = s->id;
+    p->msg.data_length = len;
+    strcpy((char*) p->data, destination);
+    send_packet(p, s->transport);
+}
+
+
+/* this is used by magic sockets to rig local sockets to
+   send the go-ahead message when they connect */
+static void local_socket_ready_notify(asocket *s)
+{
+    s->ready = local_socket_ready;
+    s->close = local_socket_close;
+    adb_write(s->fd, "OKAY", 4);
+    s->ready(s);
+}
+
+/* this is used by magic sockets to rig local sockets to
+   send the failure message if they are closed before
+   connected (to avoid closing them without a status message) */
+static void local_socket_close_notify(asocket *s)
+{
+    s->ready = local_socket_ready;
+    s->close = local_socket_close;
+    sendfailmsg(s->fd, "closed");
+    s->close(s);
+}
+
+unsigned unhex(unsigned char *s, int len)
+{
+    unsigned n = 0, c;
+
+    while(len-- > 0) {
+        switch((c = *s++)) {
+        case '0': case '1': case '2':
+        case '3': case '4': case '5':
+        case '6': case '7': case '8':
+        case '9':
+            c -= '0';
+            break;
+        case 'a': case 'b': case 'c':
+        case 'd': case 'e': case 'f':
+            c = c - 'a' + 10;
+            break;
+        case 'A': case 'B': case 'C':
+        case 'D': case 'E': case 'F':
+            c = c - 'A' + 10;
+            break;
+        default:
+            return 0xffffffff;
+        }
+
+        n = (n << 4) | c;
+    }
+
+    return n;
+}
+
+/* skip_host_serial return the position in a string
+   skipping over the 'serial' parameter in the ADB protocol,
+   where parameter string may be a host:port string containing
+   the protocol delimiter (colon). */
+char *skip_host_serial(char *service) {
+    char *first_colon, *serial_end;
+
+    first_colon = strchr(service, ':');
+    if (!first_colon) {
+        /* No colon in service string. */
+        return NULL;
+    }
+    serial_end = first_colon;
+    if (isdigit(serial_end[1])) {
+        serial_end++;
+        while ((*serial_end) && isdigit(*serial_end)) {
+            serial_end++;
+        }
+        if ((*serial_end) != ':') {
+            // Something other than numbers was found, reset the end.
+            serial_end = first_colon;
+        }
+    }
+    return serial_end;
+}
+
+static int smart_socket_enqueue(asocket *s, apacket *p)
+{
+    unsigned len;
+#if ADB_HOST
+    char *service = NULL;
+    char* serial = NULL;
+    transport_type ttype = kTransportAny;
+#endif
+
+    D("SS(%d): enqueue %d\n", s->id, p->len);
+
+    if(s->pkt_first == 0) {
+        s->pkt_first = p;
+        s->pkt_last = p;
+    } else {
+        if((s->pkt_first->len + p->len) > MAX_PAYLOAD) {
+            D("SS(%d): overflow\n", s->id);
+            put_apacket(p);
+            goto fail;
+        }
+
+        memcpy(s->pkt_first->data + s->pkt_first->len,
+               p->data, p->len);
+        s->pkt_first->len += p->len;
+        put_apacket(p);
+
+        p = s->pkt_first;
+    }
+
+        /* don't bother if we can't decode the length */
+    if(p->len < 4) return 0;
+
+    len = unhex(p->data, 4);
+    if((len < 1) ||  (len > 1024)) {
+        D("SS(%d): bad size (%d)\n", s->id, len);
+        goto fail;
+    }
+
+    D("SS(%d): len is %d\n", s->id, len );
+        /* can't do anything until we have the full header */
+    if((len + 4) > p->len) {
+        D("SS(%d): waiting for %d more bytes\n", s->id, len+4 - p->len);
+        return 0;
+    }
+
+    p->data[len + 4] = 0;
+
+    D("SS(%d): '%s'\n", s->id, (char*) (p->data + 4));
+
+#if ADB_HOST
+    service = (char *)p->data + 4;
+    if(!strncmp(service, "host-serial:", strlen("host-serial:"))) {
+        char* serial_end;
+        service += strlen("host-serial:");
+
+        // serial number should follow "host:" and could be a host:port string.
+        serial_end = skip_host_serial(service);
+        if (serial_end) {
+            *serial_end = 0; // terminate string
+            serial = service;
+            service = serial_end + 1;
+        }
+    } else if (!strncmp(service, "host-usb:", strlen("host-usb:"))) {
+        ttype = kTransportUsb;
+        service += strlen("host-usb:");
+    } else if (!strncmp(service, "host-local:", strlen("host-local:"))) {
+        ttype = kTransportLocal;
+        service += strlen("host-local:");
+    } else if (!strncmp(service, "host:", strlen("host:"))) {
+        ttype = kTransportAny;
+        service += strlen("host:");
+    } else {
+        service = NULL;
+    }
+
+    if (service) {
+        asocket *s2;
+
+            /* some requests are handled immediately -- in that
+            ** case the handle_host_request() routine has sent
+            ** the OKAY or FAIL message and all we have to do
+            ** is clean up.
+            */
+        if(handle_host_request(service, ttype, serial, s->peer->fd, s) == 0) {
+                /* XXX fail message? */
+            D( "SS(%d): handled host service '%s'\n", s->id, service );
+            goto fail;
+        }
+        if (!strncmp(service, "transport", strlen("transport"))) {
+            D( "SS(%d): okay transport\n", s->id );
+            p->len = 0;
+            return 0;
+        }
+
+            /* try to find a local service with this name.
+            ** if no such service exists, we'll fail out
+            ** and tear down here.
+            */
+        s2 = create_host_service_socket(service, serial);
+        if(s2 == 0) {
+            D( "SS(%d): couldn't create host service '%s'\n", s->id, service );
+            sendfailmsg(s->peer->fd, "unknown host service");
+            goto fail;
+        }
+
+            /* we've connected to a local host service,
+            ** so we make our peer back into a regular
+            ** local socket and bind it to the new local
+            ** service socket, acknowledge the successful
+            ** connection, and close this smart socket now
+            ** that its work is done.
+            */
+        adb_write(s->peer->fd, "OKAY", 4);
+
+        s->peer->ready = local_socket_ready;
+        s->peer->close = local_socket_close;
+        s->peer->peer = s2;
+        s2->peer = s->peer;
+        s->peer = 0;
+        D( "SS(%d): okay\n", s->id );
+        s->close(s);
+
+            /* initial state is "ready" */
+        s2->ready(s2);
+        return 0;
+    }
+#else /* !ADB_HOST */
+    if (s->transport == NULL) {
+        char* error_string = "unknown failure";
+        s->transport = acquire_one_transport (CS_ANY,
+                kTransportAny, NULL, &error_string);
+
+        if (s->transport == NULL) {
+            sendfailmsg(s->peer->fd, error_string);
+            goto fail;
+        }
+    }
+#endif
+
+    if(!(s->transport) || (s->transport->connection_state == CS_OFFLINE)) {
+           /* if there's no remote we fail the connection
+            ** right here and terminate it
+            */
+        sendfailmsg(s->peer->fd, "device offline (x)");
+        goto fail;
+    }
+
+
+        /* instrument our peer to pass the success or fail
+        ** message back once it connects or closes, then
+        ** detach from it, request the connection, and
+        ** tear down
+        */
+    s->peer->ready = local_socket_ready_notify;
+    s->peer->close = local_socket_close_notify;
+    s->peer->peer = 0;
+        /* give him our transport and upref it */
+    s->peer->transport = s->transport;
+
+    connect_to_remote(s->peer, (char*) (p->data + 4));
+    s->peer = 0;
+    s->close(s);
+    return 1;
+
+fail:
+        /* we're going to close our peer as a side-effect, so
+        ** return -1 to signal that state to the local socket
+        ** who is enqueueing against us
+        */
+    s->close(s);
+    return -1;
+}
+
+static void smart_socket_ready(asocket *s)
+{
+    D("SS(%d): ready\n", s->id);
+}
+
+static void smart_socket_close(asocket *s)
+{
+    D("SS(%d): closed\n", s->id);
+    if(s->pkt_first){
+        put_apacket(s->pkt_first);
+    }
+    if(s->peer) {
+        s->peer->peer = 0;
+        s->peer->close(s->peer);
+        s->peer = 0;
+    }
+    free(s);
+}
+
+asocket *create_smart_socket(void (*action_cb)(asocket *s, const char *act))
+{
+    D("Creating smart socket \n");
+    asocket *s = calloc(1, sizeof(asocket));
+    if (s == NULL) fatal("cannot allocate socket");
+    s->enqueue = smart_socket_enqueue;
+    s->ready = smart_socket_ready;
+    s->close = smart_socket_close;
+    s->extra = action_cb;
+
+    D("SS(%d): created %p\n", s->id, action_cb);
+    return s;
+}
+
+void smart_socket_action(asocket *s, const char *act)
+{
+
+}
+
+void connect_to_smartsocket(asocket *s)
+{
+    D("Connecting to smart socket \n");
+    asocket *ss = create_smart_socket(smart_socket_action);
+    s->peer = ss;
+    ss->peer = s;
+    s->ready(s);
+}