PeerStreamer

/*

 *  Copyright (c) 2010 Csaba Kiraly

 *  Copyright (c) 2010 Luca Abeni

 *

 *  This is free software; see gpl-3.0.txt

 */

#include <stdint.h>

#include <stdio.h>

#include <sys/time.h>

#include <time.h>

#include <stdlib.h>

#include <string.h>

#include <math.h>

#include <net_helper.h>

#include <peerset.h>

#include <peer.h>

#include <grapes_msg_types.h>

#include <topmanager.h>

#include <tman.h>

#include "compatibility/timer.h"

#include "topology.h"

#include "streaming.h"

#include "dbg.h"

#include "measures.h"

#include "streamer.h"

#define MIN(A,B) ((A) < (B)) ? (A) : (B)

double desired_rtt = 0.2;

double alpha_target = 0.5;

int NEIGHBORHOOD_TARGET_SIZE = 20;

double NEIGHBORHOOD_ROTATE_RATIO = 1.0;

#define TMAN_MAX_IDLE 10

#define TMAN_LOG_EVERY 1000

static struct peerset *pset;

static struct timeval tout_bmap = {10, 0};

static int counter = 0;

static int simpleRanker (const void *tin, const void *p1in, const void *p2in);

static tmanRankingFunction rankFunct = simpleRanker;

struct metadata {

  uint16_t cb_size;

  uint16_t cps;

  float recv_delay;

};

static struct metadata my_metadata;

static int cnt = 0;

static struct nodeID *me = NULL;

static unsigned char mTypes[] = {MSG_TYPE_TOPOLOGY,MSG_TYPE_TMAN};

static struct nodeID ** neighbors;

static void update_metadata(void) {

        my_metadata.cb_size = am_i_source() ? 0 : get_cb_size();

        my_metadata.recv_delay = get_receive_delay();

        my_metadata.cps = get_chunks_per_sec();

}

static int simpleRanker (const void *tin, const void *p1in, const void *p2in) {

        double t,p1,p2;

        t = *((const double *)tin);

        p1 = *((const double *)p1in);

        p2 = *((const double *)p2in);

        if (isnan(t) || (isnan(p1) && isnan(p2))) return 0;

        else if (isnan(p1)) return 2;

        else if (isnan(p2)) return 1;

        else return (fabs(t-p1) == fabs(t-p2))?0:(fabs(t-p1) < fabs(t-p2))?1:2;

}

int topologyInit(struct nodeID *myID, const char *config)

{

        int i;

        for (i=0;i<2;i++)

                bind_msg_type(mTypes[i]);

        update_metadata();

        me = myID;

        return (topInit(myID, &my_metadata, sizeof(my_metadata), config) && tmanInit(myID,&my_metadata, sizeof(my_metadata),rankFunct,0));

}

void topologyShutdown(void)

{

}

int topoAddNeighbour(struct nodeID *neighbour, void *metadata, int metadata_size)

{

        // TODO: check this!! Just to use this function to bootstrap ncast...

        struct metadata m = {0};        //TODO: check what metadata option should mean

        if (counter < TMAN_MAX_IDLE)

                return topAddNeighbour(neighbour,&m,sizeof(m));

        else return tmanAddNeighbour(neighbour,&m,sizeof(m));

}

static int topoParseData(const uint8_t *buff, int len)

{

        int res = -1,ncs = 0,msize;

        const struct nodeID **n; const void *m;

        if (!buff || buff[0] == MSG_TYPE_TOPOLOGY) {

                res = topParseData(buff,len);

//                if (counter <= TMAN_MAX_IDLE)

//                        counter++;

        }

        if (counter >= TMAN_MAX_IDLE && (!buff || buff[0] == MSG_TYPE_TMAN))

        {

                n = topGetNeighbourhood(&ncs);

                if (ncs) {

                m = topGetMetadata(&msize);

                res = tmanParseData(buff,len,n,ncs,m,msize);

                }

        }

  return res;

}

static const struct nodeID **topoGetNeighbourhood(int *n)

{

        int i; double d;

        if (counter > TMAN_MAX_IDLE) {

                uint8_t *mdata; int msize;

                *n = tmanGetNeighbourhoodSize();

                if (neighbors) free(neighbors);

                neighbors = calloc(*n,sizeof(struct nodeID *));

                tmanGetMetadata(&msize);

                mdata = calloc(*n,msize);

                tmanGivePeers(*n,neighbors,(void *)mdata);

                if (cnt % TMAN_LOG_EVERY == 0) {

                        fprintf(stderr,"abouttopublish,%s,%s,,Tman_chunk_delay,%f\n",node_addr(me),node_addr(me),my_metadata.recv_delay);

                        for (i=0;i<(*n) && i<NEIGHBORHOOD_TARGET_SIZE;i++) {

                                d = *((double *)(mdata+i*msize));

                                fprintf(stderr,"abouttopublish,%s,",node_addr(me));

                                fprintf(stderr,"%s,,Tman_chunk_delay,%f\n",node_addr(neighbors[i]),d);

                        }

                        fprintf(stderr,"abouttopublish,%s,%s,,Tman_neighborhood_size,%d\n\n",node_addr(me),node_addr(me),*n);

                }

                free(mdata);

                return (const struct nodeID **)neighbors;

        }

        else

                return topGetNeighbourhood(n);

}

static void topoAddToBL (struct nodeID *id)

{

        if (counter >= TMAN_MAX_IDLE)

                tmanAddToBlackList(id);

//        else

                topAddToBlackList(id);

}

void add_peer(const struct nodeID *id, const struct metadata *m)

{

      dprintf("Adding %s to neighbourhood! cb_size:%d\n", node_addr(id), m?m->cb_size:-1);

      peerset_add_peer(pset, id);

      if (m) peerset_get_peer(pset, id)->cb_size = m->cb_size;

      /* add measures here */

      add_measures(id);

      send_bmap(id);

}

void remove_peer(const struct nodeID *id)

{

      dprintf("Removing %s from neighbourhood!\n", node_addr(id));

      /* add measures here */

      delete_measures(id);

      peerset_remove_peer(pset, id);

}

//get the rtt. Currenly only MONL version is supported

static double get_rtt_of(const struct nodeID* n){

#ifdef MONL

  return get_rtt(n);

#else

  return NAN;

#endif

}

//returns: 1:yes 0:no -1:unknown

int desiredness(const struct nodeID* n) {

  double rtt = get_rtt_of(n);

  return isnan(rtt) ? -1 : ((rtt <= desired_rtt) ? 1 : 0);

}

bool is_desired(const struct nodeID* n) {

  return (desiredness(n) == 1);

}

// The usual shuffle

static void shuffle(void *base, size_t nmemb, size_t size) {

  int i;

  unsigned char t[size];

  unsigned char* b = base;

  for (i = nmemb - 1; i > 0; i--) {

    int newpos = (rand()/(RAND_MAX + 1.0)) * (i + 1);

    memcpy(t, b + size * newpos, size);

    memmove(b + size * newpos, b + size * i, size);

    memcpy(b + size * i, t, size);

  }

}

static void nidset_shuffle(const struct nodeID **base, size_t nmemb) {

  shuffle(base, nmemb, sizeof(struct nodeID *));

}

static int nidset_filter(const struct nodeID **dst, size_t *dst_size, const struct nodeID **src, size_t src_size, bool(*f)(const struct nodeID *)) {

  size_t i;

  size_t max_size = *dst_size;

  *dst_size = 0;

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

    if (f(src[i])) {

      if (*dst_size < max_size) {

        dst[(*dst_size)++] = src[i];

      } else {

        return -1;

      }

    }

  }

  return 0;

}

// B \ A

static int nidset_complement(const struct nodeID **dst, size_t *dst_size, const struct nodeID **bs, size_t bs_size, const struct nodeID **as, size_t as_size) {

  size_t i, j;

  size_t max_size = *dst_size;

  *dst_size = 0;

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

    for (j = 0; j < as_size; j++) {

      if (bs[i] == as[j]) {

        break;

      }

    }

    if (j >= as_size) {

      if (*dst_size < max_size) {

        dst[(*dst_size)++] = bs[i];

      } else {

        return -1;

      }

    }

  }

  return 0;

}

static bool nidset_find(size_t *i, const struct nodeID **ids, size_t ids_size, const struct nodeID *id) {

  for (*i = 0; *i < ids_size; (*i)++) {

    if (ids[*i] == id) {

      return true;

    }

  }

  return false;

}

static int nidset_add(const struct nodeID **dst, size_t *dst_size, const struct nodeID **as, size_t as_size, const struct nodeID **bs, size_t bs_size) {

  size_t i;

  size_t max_size = *dst_size;

  i = MIN(as_size, max_size);

  memcpy(dst, as, i * sizeof(struct nodeID*));

  *dst_size = i;

  if (i < as_size) return -1;

  i = MIN(bs_size, max_size - *dst_size);

  memcpy(dst + *dst_size , bs, i * sizeof(struct nodeID*));

  *dst_size += i;

  if (i < bs_size) return -1;

  return 0;

}

static int nidset_add_i(const struct nodeID **dst, size_t *dst_size, size_t max_size, const struct nodeID **as, size_t as_size) {

  size_t i;

  i = MIN(as_size, max_size - *dst_size);

  memcpy(dst + *dst_size , as, i * sizeof(struct nodeID*));

  *dst_size += i;

  if (i < as_size) return -1;

  return 0;

}

// currently it just makes the peerset grow

void update_peers(struct nodeID *from, const uint8_t *buff, int len)

{

  int n_ids, metasize, i;

  static const struct nodeID **ids;

  static const struct metadata *metas;

  struct peer *peers;

  struct timeval tnow, told;

//  dprintf("Update peers: topo_msg:%d, ",len);

//  if (from) {

//    dprintf("from:%s, ",node_addr(from));

//    if (peerset_check(pset, from) < 0) {

//      topAddNeighbour(from, NULL, 0);        //@TODO: this is agressive

//      if (!NEIGHBORHOOD_TARGET_SIZE || peerset_size(pset) < NEIGHBORHOOD_TARGET_SIZE) {

//        add_peer(from);

//      }

//    }

//  }

  if (cnt++ % 100 == 0) {

        update_metadata();

    if (counter > TMAN_MAX_IDLE) {

        tmanChangeMetadata(&my_metadata,sizeof(my_metadata));

    }

  }

  topoParseData(buff, len);

  if (!buff) {

    reg_neigh_size(peerset_size(pset));

    return;

  }

  fprintf(stderr,"Topo modify start\n");

  peers = peerset_get_peers(pset);

  for (i = 0; i < peerset_size(pset); i++) {

    fprintf(stderr," %s - RTT: %f\n", node_addr(peers[i].id) , get_rtt_of(peers[i].id));

  }

  ids = topoGetNeighbourhood(&n_ids);        //TODO handle both tman and topo

  metas = topGetMetadata(&metasize);        //TODO: check metasize

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

    if(peerset_check(pset, ids[i]) < 0) {

      if (!NEIGHBORHOOD_TARGET_SIZE || peerset_size(pset) < NEIGHBORHOOD_TARGET_SIZE) {

        add_peer(ids[i],&metas[i]);

      } else {  //rotate neighbourhood

        if (rand()/((double)RAND_MAX + 1) < NEIGHBORHOOD_ROTATE_RATIO) {

          add_peer(ids[i],&metas[i]);

        }

      }

    }

  }

  if timerisset(&tout_bmap) {

    gettimeofday(&tnow, NULL);

    timersub(&tnow, &tout_bmap, &told);

    peers = peerset_get_peers(pset);

    for (i = 0; i < peerset_size(pset); i++) {

      if ( (!timerisset(&peers[i].bmap_timestamp) && timercmp(&peers[i].creation_timestamp, &told, <) ) ||

           ( timerisset(&peers[i].bmap_timestamp) && timercmp(&peers[i].bmap_timestamp, &told, <)     )   ) {

        //if (peerset_size(pset) > 1) {        // avoid dropping our last link to the world

        topoAddToBL(peers[i].id);

        remove_peer(peers[i--].id);

        //}

      }

    }

  }

  n_ids = peerset_size(pset);

  {

    int desired_part;

    const struct nodeID *nodeids[n_ids], *desireds[n_ids], *selecteds[n_ids], *others[n_ids], *toremoves[n_ids];

    size_t nodeids_size, desireds_size, selecteds_size, others_size, toremoves_size;

    nodeids_size = desireds_size = selecteds_size = others_size = toremoves_size = n_ids;

    //compose list of nodeids

    peers = peerset_get_peers(pset);

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

      nodeids[i] = peers[i].id;

    }

    // select the alpha_target portion of desired peers

    desired_part = alpha_target * NEIGHBORHOOD_TARGET_SIZE;

    nidset_filter(desireds, &desireds_size, nodeids, nodeids_size, is_desired);

    nidset_shuffle(desireds, desireds_size);

    selecteds_size = MIN(desireds_size,desired_part);

    memcpy(selecteds, desireds, selecteds_size * sizeof(selecteds[0]));

    // random from the rest

    nidset_complement(others, &others_size, nodeids, nodeids_size, selecteds, selecteds_size);

    nidset_shuffle(others, others_size);

    nidset_add_i(selecteds, &selecteds_size, n_ids, others, NEIGHBORHOOD_TARGET_SIZE ? MIN(others_size, NEIGHBORHOOD_TARGET_SIZE - selecteds_size) : others_size);

    // finally, remove those not needed

    fprintf(stderr,"Topo remove start (peers:%d)\n", n_ids);

    nidset_complement(toremoves, &toremoves_size, nodeids, nodeids_size, selecteds, selecteds_size);

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

      fprintf(stderr," removing %s\n", node_addr(toremoves[i]));

      remove_peer(toremoves[i]);

    }

    fprintf(stderr,"Topo remove end\n");

  }

  reg_neigh_size(peerset_size(pset));

}

struct peer *nodeid_to_peer(const struct nodeID* id, int reg)

{

  struct peer *p = peerset_get_peer(pset, id);

  if (!p) {

    //fprintf(stderr,"warning: received message from unknown peer: %s!%s\n",node_addr(id), reg ? " Adding it to pset." : "");

    if (reg) {

      add_peer(id,NULL);

      p = peerset_get_peer(pset,id);

    }

  }

  return p;

}

int peers_init(void)

{

  fprintf(stderr,"peers_init\n");

  pset = peerset_init(0);

  return pset ? 1 : 0;

}

struct peerset *get_peers(void)

{

  return pset;

}