PeerStreamer

/*

 *  Copyright (c) 2009 Marco Biazzini

 *

 *  This is free software; see lgpl-2.1.txt

 */

#include <event2/event.h>

#include <arpa/inet.h>

#include <unistd.h>

#include <stdlib.h>

#include <stdio.h>

#include <stdbool.h>

#include <string.h>

#include <assert.h>

#include "net_helper.h"

#include "ml.h"

#include "config.h"

#include "grapes_msg_types.h"

#ifdef MONL

#include "mon.h"

#include "grapes_log.h"

#include "repoclient.h"

#include "grapes.h"

#endif

/**

 * libevent pointer

 */

struct event_base *base;

#define NH_BUFFER_SIZE 1000

#define NH_LOOKUP_SIZE 1000

#define NH_PACKET_TIMEOUT {0, 500*1000}

#define NH_ML_INIT_TIMEOUT {1, 0}

#define FDSSIZE 16

static int sIdx = 0;

static int rIdxML = 0;        //reveive from ML to this buffer position

static int rIdxUp = 0;        //hand up to layer above at this buffer position

typedef struct nodeID {

        socketID_handle addr;

        int connID;        // connection associated to this node, -1 if myself

        int refcnt;

#ifdef MONL

        //n quick and dirty static vector for measures TODO: make it dinamic

        MonHandler mhs[20];

        int n_mhs;

#endif

//        int addrSize;

//        int addrStringSize;

} nodeID;

typedef struct msgData_cb {

        int bIdx;        // index of the message in the proper buffer

        unsigned char msgType; // message type

        int mSize;        // message size

        bool conn_cb_called;

        bool cancelled;

} msgData_cb;

static struct nodeID **lookup_array;

static int lookup_max = NH_LOOKUP_SIZE;

static int lookup_curr = 0;

static nodeID *me; //TODO: is it possible to get rid of this (notwithstanding ml callback)??

static int timeoutFired = 0;

static bool fdTriggered = false;

// pointers to the msgs to be send

static uint8_t *sendingBuffer[NH_BUFFER_SIZE];

// pointers to the received msgs + sender nodeID

struct receivedB {

        struct nodeID *id;

        int len;

        uint8_t *data;

};

static struct receivedB receivedBuffer[NH_BUFFER_SIZE];

/**/ static int recv_counter =0; static int snd_counter =0;

static void connReady_cb (int connectionID, void *arg);

static struct nodeID *new_node(socketID_handle peer) {

        send_params params = {0,0,0,0};

        struct nodeID *res = malloc(sizeof(struct nodeID));

        if (!res) {

                 fprintf(stderr, "Net-helper : memory error\n");

                 return NULL;

        }

        memset(res, 0, sizeof(struct nodeID));

        res->addr = malloc(SOCKETID_SIZE);

        if (! res->addr) {

                free (res);

                fprintf(stderr, "Net-helper : memory error while creating a new nodeID \n");

                return NULL;

        }

        memset(res->addr, 0, SOCKETID_SIZE);

        memcpy(res->addr, peer ,SOCKETID_SIZE);

        res->refcnt = 1;

        res->connID = mlOpenConnection(peer, &connReady_cb, NULL, params);

        return res;

}

static struct nodeID **id_lookup(socketID_handle target) {

        int i,here=-1;

        for (i=0;i<lookup_curr;i++) {

                if (lookup_array[i] == NULL) {

                        if (here < 0) {

                                here = i;

                        }

                } else if (!mlCompareSocketIDs(lookup_array[i]->addr,target)) {

                        return &lookup_array[i];

                }

        }

        if (here == -1) {

                here = lookup_curr++;

        }

        if (lookup_curr > lookup_max) {

                lookup_max *= 2;

                lookup_array = realloc(lookup_array,lookup_max*sizeof(struct nodeID*));

        }

        lookup_array[here] = new_node(target);

        return &lookup_array[here];

}

static struct nodeID *id_lookup_dup(socketID_handle target) {

        return nodeid_dup(*id_lookup(target));

}

/**

 * Look for a free slot in the received buffer and allocates it for immediate use

 * @return the index of a free slot in the received msgs buffer, -1 if no free slot available.

 */

static int next_R() {

        if (receivedBuffer[rIdxML].data==NULL) {

                int ret = rIdxML;

                rIdxML = (rIdxML+1)%NH_BUFFER_SIZE;

                return ret;

        } else {

                //TODO: handle receive overload situation!

                return -1;

        }

}

/**

 * Look for a free slot in the sending buffer and allocates it for immediate use

 * @return the index of a free slot in the sending msgs buffer, -1 if no free slot available.

 */

static int next_S() {

        if (sendingBuffer[sIdx]) {

                int count;

                for (count=0;count<NH_BUFFER_SIZE;count++) {

                        sIdx = (sIdx+1)%NH_BUFFER_SIZE;

                        if (sendingBuffer[sIdx]==NULL)

                                break;

                }

                if (count==NH_BUFFER_SIZE) {

                        return -1;

                }

        }

        return sIdx;

}

/**

 * Callback used by ml to confirm its initialization. Create a valid self nodeID and register to receive data from remote peers.

 * @param local_socketID

 * @param errorstatus

 */

static void init_myNodeID_cb (socketID_handle local_socketID,int errorstatus) {

        switch (errorstatus) {

        case 0:

                me->addr = malloc(SOCKETID_SIZE);

                if (! me->addr) {

                        fprintf(stderr, "Net-helper : memory error while creating my new nodeID \n");

                        return;

                }

                memcpy(me->addr,local_socketID,SOCKETID_SIZE);

        //        me->addrSize = SOCKETID_SIZE;

        //        me->addrStringSize = SOCKETID_STRING_SIZE;

                me->connID = -1;

                me->refcnt = 1;

        //        fprintf(stderr,"Net-helper init : received my own socket: %s.\n",node_addr(me));

                break;

        case -1:

                //

                fprintf(stderr,"Net-helper init : socket error occurred in ml while creating socket\n");

                exit(1);

                break;

        case 1:

                //

                fprintf(stderr,"Net-helper init : NAT traversal failed while creating socket\n");

                exit(1);

                break;

        case 2:

            fprintf(stderr,"Net-helper init : NAT traversal timeout while creating socket\n");

            fprintf(stderr,"Net-helper init : Retrying without STUN\n");

            mlSetStunServer(0,NULL);

            break;

        default :        // should never happen

                //

                fprintf(stderr,"Net-helper init : Unknown error in ml while creating socket\n");

        }

}

/**

 * Timeout callback to be set in the eventlib loop as needed

 * @param socket

 * @param flag

 * @param arg

 */

static void t_out_cb (int socket, short flag, void* arg) {

        timeoutFired = 1;

//        fprintf(stderr,"TIMEOUT!!!\n");

//        event_base_loopbreak(base);

}

/**

 * File descriptor readable callback to be set in the eventlib loop as needed

 */

static void fd_cb (int fd, short flag, void* arg)

{

  //fprintf(stderr, "\twait4data: fd %d triggered\n", fd);

  fdTriggered = true;

  *((bool*)arg) = true;

}

/**

 * Callback called by ml when a remote node ask for a connection

 * @param connectionID

 * @param arg

 */

static void receive_conn_cb(int connectionID, void *arg) {

//    fprintf(stderr, "Net-helper : remote peer opened the connection %d with arg = %d\n", connectionID,(int)arg);

}

void free_sending_buffer(int i)

{

        free(sendingBuffer[i]);

        sendingBuffer[i] = NULL;

}

/**

 * Callback called by the ml when a connection is ready to be used to send data to a remote peer

 * @param connectionID

 * @param arg

 */

static void connReady_cb (int connectionID, void *arg) {

        char mt;

        msgData_cb *p;

        p = (msgData_cb *)arg;

        if (p == NULL) return;

        if (p->cancelled) {

            free(p);

            return;

        }

        mlSendData(connectionID,(char *)(sendingBuffer[p->bIdx]),p->mSize,p->msgType,NULL);

/**/        mt = ((char*)sendingBuffer[p->bIdx])[0]; ++snd_counter;

        if (mt!=MSG_TYPE_TOPOLOGY &&

                mt!=MSG_TYPE_CHUNK && mt!=MSG_TYPE_SIGNALLING) {

                        fprintf(stderr,"Net-helper ERROR! Sent message # %d of type %c and size %d\n",

                                snd_counter,mt+'0', p->mSize);}

        free_sending_buffer(p->bIdx);

//        fprintf(stderr,"Net-helper: Message # %d for connection %d sent!\n ", p->bIdx,connectionID);

        //        event_base_loopbreak(base);

        p->conn_cb_called = true;

}

/**

 * Callback called by ml when a connection error occurs

 * @param connectionID

 * @param arg

 */

static void connError_cb (int connectionID, void *arg) {

        // simply get rid of the msg in the buffer....

        msgData_cb *p;

        p = (msgData_cb *)arg;

        if (p != NULL) {

                fprintf(stderr,"Net-helper: Connection %d could not be established to send msg %d.\n ", connectionID,p->bIdx);

                if (p->cancelled) {

                        free(p);//p->mSize = -1;

                } else {

                        p->conn_cb_called = true;

                }

        }

        //        event_base_loopbreak(base);

}

/**

 * Callback to receive data from ml

 * @param buffer

 * @param buflen

 * @param msgtype

 * @param arg

 */

static void recv_data_cb(char *buffer, int buflen, unsigned char msgtype, recv_params *arg) {

// TODO: lacks a void* arg... moreover: recv_params has a msgtype, but there is also a msgtype explicit argument...

        char str[SOCKETID_STRING_SIZE];

//        fprintf(stderr, "Net-helper : called back with some news...\n");

/**/ ++recv_counter;

        if (arg->remote_socketID != NULL)

                mlSocketIDToString(arg->remote_socketID,str,SOCKETID_STRING_SIZE);

        else

                sprintf(str,"!Unknown!");

        if (arg->nrMissingBytes || !arg->firstPacketArrived) {

            fprintf(stderr, "Net-helper : corrupted message arrived from %s\n",str);

/**/    fprintf(stderr, "\tMessage # %d -- Message type: %hhd -- Missing # %d bytes%s\n",

                        recv_counter, buffer[0],arg->nrMissingBytes, arg->firstPacketArrived?"":", Missing first!");

        }

        else {

        //        fprintf(stderr, "Net-helper : message arrived from %s\n",str);

                // buffering the received message only if possible, otherwise ignore it...

                int index = next_R();

                if (index<0) {

                        fprintf(stderr,"Net-helper: receive buffer full\n ");

                        return;

                } else {

                        receivedBuffer[index].data = malloc(buflen);

                        if (receivedBuffer[index].data == NULL) {

                                fprintf(stderr,"Net-helper: memory full, can't receive!\n ");

                                return;

                        }

                        receivedBuffer[index].len = buflen;

                        memcpy(receivedBuffer[index].data,buffer,buflen);

                          // save the socketID of the sender

                        receivedBuffer[index].id = id_lookup_dup(arg->remote_socketID);

                }

  }

//        event_base_loopbreak(base);

}

struct nodeID *net_helper_init(const char *IPaddr, int port, const char *config) {

        struct timeval tout = NH_ML_INIT_TIMEOUT;

        int s, i;

        struct tag *cfg_tags;

        const char *res;

        const char *stun_server = "stun.ekiga.net";

        int stun_port = 3478;

        const char *repo_address = "79.120.193.115:9832";

        int publish_interval = 60;

        base = event_base_new();

        lookup_array = calloc(lookup_max,sizeof(struct nodeID *));

        cfg_tags = config_parse(config);

        res = config_value_str(cfg_tags, "stun_server");

        if (res) {

                stun_server = res;

        }

        config_value_int(cfg_tags, "stun_port", &stun_port);

        res = config_value_str(cfg_tags, "repo_address");

        if (res) {

                repo_address = res;

        }

        config_value_int(cfg_tags, "publish_interval", &publish_interval);

        me = malloc(sizeof(nodeID));

        if (me == NULL) {

                return NULL;

        }

        memset(me,0,sizeof(nodeID));

        me->connID = -10;        // dirty trick to spot later if the ml has called back ...

        me->refcnt = 1;

        for (i=0;i<NH_BUFFER_SIZE;i++) {

                sendingBuffer[i] = NULL;

                receivedBuffer[i].data = NULL;

        }

        mlRegisterErrorConnectionCb(&connError_cb);

        mlRegisterRecvConnectionCb(&receive_conn_cb);

        s = mlInit(1, tout, port, IPaddr, stun_port, stun_server, &init_myNodeID_cb, base);

        if (s < 0) {

                fprintf(stderr, "Net-helper : error initializing ML!\n");

                free(me);

                return NULL;

        }

#ifdef MONL

{

        void *repoclient;

        eventbase = base;

        // Initialize logging

        grapesInitLog(DCLOG_WARNING, NULL, NULL);

        repInit("");

        repoclient = repOpen(repo_address, publish_interval);        //repository.napa-wine.eu

        if (repoclient == NULL) fatal("Unable to initialize repoclient");

        monInit(base, repoclient);

}

#endif

        free(cfg_tags);

        while (me->connID<-1) {

        //        event_base_once(base,-1, EV_TIMEOUT, &t_out_cb, NULL, &tout);

                event_base_loop(base,EVLOOP_ONCE);

        }

        timeoutFired = 0;

//        fprintf(stderr,"Net-helper init : back from init!\n");

        return me;

}

void bind_msg_type (unsigned char msgtype) {

                        mlRegisterRecvDataCb(&recv_data_cb,msgtype);

}

void send_to_peer_cb(int fd, short event, void *arg)

{

        msgData_cb *p = (msgData_cb *) arg;

        if (p->conn_cb_called) {

                free(p);

        }

        else { //don't send it anymore

                free_sending_buffer(p->bIdx);

                p->cancelled = true;

                // don't free p, the other timeout will do it

        }

}

/**

 * Called by the application to send data to a remote peer

 * @param from

 * @param to

 * @param buffer_ptr

 * @param buffer_size

 * @return The dimension of the buffer or -1 if a connection error occurred.

 */

int send_to_peer(const struct nodeID *from, struct nodeID *to, const uint8_t *buffer_ptr, int buffer_size)

{

        msgData_cb *p;

        int current;

        send_params params = {0,0,0,0};

        if (buffer_size <= 0) {

                fprintf(stderr,"Net-helper: message size problematic: %d\n", buffer_size);

                return buffer_size;

        }

        // if buffer is full, discard the message and return an error flag

        int index = next_S();

        if (index<0) {

                // free(buffer_ptr);

                fprintf(stderr,"Net-helper: send buffer full\n ");

                return -1;

        }

        sendingBuffer[index] = malloc(buffer_size);

        if (! sendingBuffer[index]){

                fprintf(stderr,"Net-helper: memory full, can't send!\n ");

                return -1;

        }

        memset(sendingBuffer[index],0,buffer_size);

        memcpy(sendingBuffer[index],buffer_ptr,buffer_size);

        // free(buffer_ptr);

        p = malloc(sizeof(msgData_cb));

        p->bIdx = index; p->mSize = buffer_size; p->msgType = (unsigned char)buffer_ptr[0]; p->conn_cb_called = false; p->cancelled = false;

        current = p->bIdx;

        to->connID = mlOpenConnection(to->addr,&connReady_cb,p, params);

        if (to->connID<0) {

                free_sending_buffer(current);

                fprintf(stderr,"Net-helper: Couldn't get a connection ID to send msg %d.\n ", p->bIdx);

                free(p);

                return -1;

        }

        else {

                struct timeval timeout = NH_PACKET_TIMEOUT;

                event_base_once(base, -1, EV_TIMEOUT, send_to_peer_cb, (void *) p, &timeout);

                return buffer_size; //p->mSize;

        }

}

/**

 * Called by an application to receive data from remote peers

 * @param local

 * @param remote

 * @param buffer_ptr

 * @param buffer_size

 * @return The number of received bytes or -1 if some error occurred.

 */

int recv_from_peer(const struct nodeID *local, struct nodeID **remote, uint8_t *buffer_ptr, int buffer_size)

{

        int size;

        if (receivedBuffer[rIdxUp].data==NULL) {        //block till first message arrives

                wait4data(local, NULL, NULL);

        }

        assert(receivedBuffer[rIdxUp].data && receivedBuffer[rIdxUp].id);

        (*remote) = receivedBuffer[rIdxUp].id;

        // retrieve a msg from the buffer

        size = receivedBuffer[rIdxUp].len;

        if (size>buffer_size) {

                fprintf(stderr, "Net-helper : recv_from_peer: buffer too small (size:%d > buffer_size: %d)!\n",size,buffer_size);

                return -1;

        }

        memcpy(buffer_ptr, receivedBuffer[rIdxUp].data, size);

        free(receivedBuffer[rIdxUp].data);

        receivedBuffer[rIdxUp].data = NULL;

        receivedBuffer[rIdxUp].id = NULL;

        rIdxUp = (rIdxUp+1)%NH_BUFFER_SIZE;

//        fprintf(stderr, "Net-helper : I've got mail!!!\n");

        return size;

}

int wait4data(const struct nodeID *n, struct timeval *tout, int *fds) {

        struct event *timeout_ev = NULL;

        struct event *fd_ev[FDSSIZE];

        bool fd_triggered[FDSSIZE] = { false };

        int i;

//        fprintf(stderr,"Net-helper : Waiting for data to come...\n");

        if (tout) {        //if tout==NULL, loop wait infinitely

          timeout_ev = event_new(base, -1, EV_TIMEOUT, &t_out_cb, NULL);

          event_add(timeout_ev, tout);

        }

        for (i = 0; fds && fds[i] != -1; i ++) {

          if (i >= FDSSIZE) {

            fprintf(stderr, "Can't listen on more than %d file descriptors!\n", FDSSIZE);

            break;

          }

          fd_ev[i] = event_new(base, fds[i], EV_READ, &fd_cb, &fd_triggered[i]);

          event_add(fd_ev[i], NULL);

        }

        while(receivedBuffer[rIdxUp].data==NULL && timeoutFired==0 && fdTriggered==0) {

        //        event_base_dispatch(base);

                event_base_loop(base,EVLOOP_ONCE);

        }

        //delete one-time events

        if (timeout_ev) {

          if (!timeoutFired) event_del(timeout_ev);

          event_free(timeout_ev);

        }

        for (i = 0; fds && fds[i] != -1; i ++) {

          if (! fd_triggered[i]) {

            fds[i] = -2;

            event_del(fd_ev[i]);

          //} else {

            //fprintf(stderr, "\twait4data: fd %d triggered\n", fds[i]);

          }

          event_free(fd_ev[i]);

        }

        if (fdTriggered) {

          fdTriggered = false;

          //fprintf(stderr, "\twait4data: fd event\n");

          return 2;

        } else if (timeoutFired) {

          timeoutFired = 0;

          //fprintf(stderr, "\twait4data: timed out\n");

          return 0;

        } else if (receivedBuffer[rIdxUp].data!=NULL) {

          //fprintf(stderr, "\twait4data: ML receive\n");

          return 1;

        } else {

          fprintf(stderr, "BUG in wait4data\n");

          exit(EXIT_FAILURE);

        }

}

socketID_handle getRemoteSocketID(const char *ip, int port) {

        char str[SOCKETID_STRING_SIZE];

        socketID_handle h;

        snprintf(str, SOCKETID_STRING_SIZE, "%s:%d-%s:%d", ip, port, ip, port);

        h = malloc(SOCKETID_SIZE);

        mlStringToSocketID(str, h);

        return h;

}

struct nodeID *create_node(const char *rem_IP, int rem_port) {

        socketID_handle s;

        struct nodeID *remote;

        s = getRemoteSocketID(rem_IP, rem_port);

        remote = id_lookup_dup(s);

        free(s);

        return remote;

}

// TODO: check why closing the connection is annoying for the ML

void nodeid_free(struct nodeID *n) {

        if (n && (--(n->refcnt) == 1)) {

/*

                struct nodeID **npos;

        //        mlCloseConnection(n->connID);

                npos = id_lookup(n->addr);

                *npos = NULL;

                mlCloseSocket(n->addr);

                free(n);

*/

        }

}

const char *node_addr(const struct nodeID *s)

{

  static char addr[256];

  // TODO: mlSocketIDToString always return 0 !!!

  int r = mlSocketIDToString(s->addr,addr,256);

  if (!r)

          return addr;

  else

          return "";

}

struct nodeID *nodeid_dup(struct nodeID *s)

{

        s->refcnt++;

        return s;

}

int nodeid_equal(const struct nodeID *s1, const struct nodeID *s2)

{

        return (mlCompareSocketIDs(s1->addr,s2->addr) == 0);

}

int nodeid_dump(uint8_t *b, const struct nodeID *s, size_t max_write_size)

{

  if (max_write_size < SOCKETID_STRING_SIZE) return -1;

  mlSocketIDToString(s->addr,(char *)b,SOCKETID_STRING_SIZE);

  //fprintf(stderr,"Dumping nodeID : ho scritto %s (%d bytes)\n",b, strlen((char *)b));

//        memcpy(b, s->addr,SOCKETID_SIZE);//sizeof(struct sockaddr_in6)*2

//        return SOCKETID_SIZE;//sizeof(struct sockaddr_in6)*2;

  return 1 + strlen((char *)b);        //terminating \0 IS included in the size

}

struct nodeID *nodeid_undump(const uint8_t *b, int *len)

{

  uint8_t sid[SOCKETID_SIZE];

  socketID_handle h = (socketID_handle) sid;

  mlStringToSocketID((char *)b,h);

  *len = strlen((char*)b) + 1;

  return id_lookup_dup(h);

}