erl_node_tables.c

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#endif
    res = hash_table_sz(&erts_node_table) + node_entries*sizeof(ErlNode);
    if (lock)
	erts_smp_mtx_unlock(&erts_node_table_mtx);
    return res;
}

void
erts_node_table_info(int to, void *to_arg)
{
    int lock = !ERTS_IS_CRASH_DUMPING;
    if (lock)
	erts_smp_mtx_lock(&erts_node_table_mtx);
    hash_info(to, to_arg, &erts_node_table);
    if (lock)
	erts_smp_mtx_unlock(&erts_node_table_mtx);
}


ErlNode *erts_find_or_insert_node(Eterm sysname, Uint creation)
{
    ErlNode *res;
    ErlNode ne;
    ne.sysname = sysname;
    ne.creation = creation;
    erts_smp_mtx_lock(&erts_node_table_mtx);
    res = hash_put(&erts_node_table, (void *) &ne);
    ASSERT(res);
    if (res != erts_this_node) {
	long refc = erts_refc_inctest(&res->refc, 0);
	if (refc < 2) /* New or pending delete */
	    erts_refc_inc(&res->refc, 1);
    }
    erts_smp_mtx_unlock(&erts_node_table_mtx);
    return res;
}

void erts_delete_node(ErlNode *enp)
{
    ASSERT(enp != erts_this_node);
    if(enp != erts_this_node) {
	erts_smp_mtx_lock(&erts_node_table_mtx);
	/*
	 * Another thread might have looked up this node after we
	 * decided to delete it (refc became zero). If so, the other
	 * thread incremented refc twice. Once for the new reference
	 * and once for this thread. Therefore, delete node if refc
	 * is 0 or -1 after a decrement.
	 */
	if (erts_refc_dectest(&enp->refc, -1) <= 0)
	    (void) hash_erase(&erts_node_table, (void *) enp);
	erts_smp_mtx_unlock(&erts_node_table_mtx);
    }
}

struct pn_data {
    int to;
    void *to_arg;
    Eterm sysname;
    int no_sysname;
    int no_total;
};

static void print_node(void *venp, void *vpndp)
{
    struct pn_data *pndp = ((struct pn_data *) vpndp);
    ErlNode *enp = ((ErlNode *) venp);

    if(pndp->sysname == NIL
       || enp->sysname == pndp->sysname) {
	if (pndp->no_sysname == 0) {
	    erts_print(pndp->to, pndp->to_arg, "Creation:");
	}
	if(pndp->sysname == NIL) {
	    erts_print(pndp->to, pndp->to_arg, "Name: %T ", enp->sysname);
	}
	erts_print(pndp->to, pndp->to_arg, " %d", enp->creation);
#ifdef DEBUG
	erts_print(pndp->to, pndp->to_arg, " (refc=%ld)",
		   erts_refc_read(&enp->refc, 1));
#endif
	pndp->no_sysname++;
    }
    pndp->no_total++;
}

void erts_print_node_info(int to,
			  void *to_arg,
			  Eterm sysname,
			  int *no_sysname,
			  int *no_total)
{
    int lock = !ERTS_IS_CRASH_DUMPING;
    struct pn_data pnd;

    pnd.to = to;
    pnd.to_arg = to_arg;
    pnd.sysname = sysname;
    pnd.no_sysname = 0;
    pnd.no_total = 0;

    if (lock)
	erts_smp_mtx_lock(&erts_node_table_mtx);
    hash_foreach(&erts_node_table, print_node, (void *) &pnd);
    if (pnd.no_sysname != 0) {
	erts_print(to, to_arg, "\n");
    }
    if (lock)
	erts_smp_mtx_unlock(&erts_node_table_mtx);

    if(no_sysname)
	*no_sysname = pnd.no_sysname;
    if(no_total)
	*no_total = pnd.no_total;
}

/* ----------------------------------------------------------------------- */

void
erts_set_this_node(Eterm sysname, Uint creation)
{
    erts_smp_mtx_lock(&erts_node_table_mtx);
    erts_smp_mtx_lock(&erts_dist_table_mtx);

    (void) hash_erase(&erts_dist_table, (void *) erts_this_dist_entry);
    erts_this_dist_entry->sysname = sysname;
    erts_this_dist_entry->creation = creation;
    (void) hash_put(&erts_dist_table, (void *) erts_this_dist_entry);

    (void) hash_erase(&erts_node_table, (void *) erts_this_node);
    erts_this_node->sysname = sysname;
    erts_this_node->creation = creation;
    (void) hash_put(&erts_node_table, (void *) erts_this_node);

    erts_smp_mtx_unlock(&erts_dist_table_mtx);
    erts_smp_mtx_unlock(&erts_node_table_mtx);

}

void erts_init_node_tables(void)
{
    HashFunctions f;

    f.hash  = (H_FUN)			dist_table_hash;
    f.cmp   = (HCMP_FUN)		dist_table_cmp;
    f.alloc = (HALLOC_FUN)		dist_table_alloc;
    f.free  = (HFREE_FUN)		dist_table_free;

    erts_this_dist_entry = erts_alloc(ERTS_ALC_T_DIST_ENTRY, sizeof(DistEntry));
    dist_entries = 1;

    hash_init(ERTS_ALC_T_DIST_TABLE, &erts_dist_table, "dist_table", 11, f);

    erts_hidden_dist_entries			= NULL;
    erts_visible_dist_entries			= NULL;
    erts_not_connected_dist_entries		= NULL;
    erts_no_of_hidden_dist_entries		= 0;
    erts_no_of_visible_dist_entries		= 0;
    erts_no_of_not_connected_dist_entries	= 0;

    erts_this_dist_entry->next			= NULL;
    erts_this_dist_entry->prev			= NULL;
    erts_refc_init(&erts_this_dist_entry->refc, 1); /* erts_this_node */
    erts_this_dist_entry->sysname		= am_Noname;
    erts_this_dist_entry->cid			= NIL;
    erts_this_dist_entry->node_links		= NULL;
    erts_this_dist_entry->nlinks		= NULL;
    erts_this_dist_entry->monitors		= NULL;
    erts_this_dist_entry->status		= 0;
    erts_this_dist_entry->flags			= 0;
    erts_this_dist_entry->cache			= NULL;
    erts_this_dist_entry->version		= 0;

    (void) hash_put(&erts_dist_table, (void *) erts_this_dist_entry);

    f.hash  = (H_FUN)      			node_table_hash;
    f.cmp   = (HCMP_FUN)   			node_table_cmp;
    f.alloc = (HALLOC_FUN) 			node_table_alloc;
    f.free  = (HFREE_FUN)  			node_table_free;

    hash_init(ERTS_ALC_T_NODE_TABLE, &erts_node_table, "node_table", 11, f);

    erts_this_node = erts_alloc(ERTS_ALC_T_NODE_ENTRY, sizeof(ErlNode));
    node_entries = 1;

    erts_refc_init(&erts_this_node->refc, 1); /* The system itself */
    erts_this_node->sysname			= am_Noname;
    erts_this_node->creation			= 0;
    erts_this_node->dist_entry			= erts_this_dist_entry;

    (void) hash_put(&erts_node_table, (void *) erts_this_node);

#ifdef ERTS_SMP
    {
	int i;
	for (i = 0; i < ERTS_NO_OF_DIST_ENTRY_MUTEXES; i++)
	    erts_smp_mtx_init(&dist_entry_mutexes[i], "dist_entry");
	erts_this_dist_entry->mtxp = &dist_entry_mutexes[0];
	erts_smp_mtx_init(&erts_node_table_mtx, "node_table");
	erts_smp_mtx_init(&erts_dist_table_mtx, "dist_table");
    }
#endif

    references_atoms_need_init = 1;
}

#ifdef ERTS_SMP
void
erts_lock_node_tables_and_entries(void)
{
    int i;
    for (i = 0; i < ERTS_NO_OF_DIST_ENTRY_MUTEXES; i++)
	erts_smp_mtx_lock(&dist_entry_mutexes[i]);
    erts_smp_mtx_lock(&erts_node_table_mtx);
    erts_smp_mtx_lock(&erts_dist_table_mtx);
}

void
erts_unlock_node_tables_and_entries(void)
{
    int i;
    erts_smp_mtx_unlock(&erts_dist_table_mtx);
    erts_smp_mtx_unlock(&erts_node_table_mtx);
    for (i = ERTS_NO_OF_DIST_ENTRY_MUTEXES-1; i >= 0; i--)
	erts_smp_mtx_unlock(&dist_entry_mutexes[i]);
}

#ifdef ERTS_ENABLE_LOCK_CHECK
int erts_lc_is_dist_entry_locked(DistEntry *dep)
{
    return erts_smp_lc_mtx_is_locked(dep->mtxp);
}
#endif
#endif

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *\
 * The following is only supposed to be used for testing, and debugging.     *
 *                                                                           *
 * erts_get_node_and_dist_references() returns a table of all references to  *
 * all entries in the node and dist tables. The hole system will be searched *
 * at once. This will give a consistent view over the references, but can    *
 * can damage the real-time properties of the system.                        *
\* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#include "erl_db.h"

#undef  INIT_AM
#define INIT_AM(S) AM_ ## S = am_atom_put(#S, sizeof(#S) - 1)

static Eterm AM_heap;
static Eterm AM_link;
static Eterm AM_monitor;
static Eterm AM_process;
static Eterm AM_port;
static Eterm AM_ets;
static Eterm AM_binary;
static Eterm AM_match_spec;
static Eterm AM_control;
static Eterm AM_dist;
static Eterm AM_node;
static Eterm AM_dist_references;
static Eterm AM_node_references;
static Eterm AM_system;
static Eterm AM_timer;
#ifdef HYBRID
static Eterm AM_processes;
#endif

static void setup_reference_table(void);
static Eterm reference_table_term(Uint **hpp, Uint *szp);
static void delete_reference_table(void);

#if BIG_UINT_HEAP_SIZE > 3 /* 2-tuple */
#define ID_HEAP_SIZE BIG_UINT_HEAP_SIZE
#else
#define ID_HEAP_SIZE 3 /* 2-tuple */
#endif

typedef struct node_referrer_ {
    struct node_referrer_ *next;
    int heap_ref;
    int link_ref;
    int monitor_ref;
    int ets_ref;
    int bin_ref;
    int timer_ref;
    int system_ref;
    Eterm id;
    Uint id_heap[ID_HEAP_SIZE];
} NodeReferrer;

typedef struct {
    ErlNode *node;
    NodeReferrer *referrers;
} ReferredNode;

typedef struct dist_referrer_ {
    struct dist_referrer_ *next;
    int node_ref;
    int ctrl_ref;
    Eterm id;
    Uint creation;
} DistReferrer;

typedef struct {
    DistEntry *dist;
    DistReferrer *referrers;
} ReferredDist;

typedef struct inserted_bin_ {
    struct inserted_bin_ *next;
    Binary *bin_val;
} InsertedBin;

static ReferredNode *referred_nodes;
static int no_referred_nodes;
static ReferredDist *referred_dists;
static int no_referred_dists;
static InsertedBin *inserted_bins;

Eterm
erts_get_node_and_dist_references(struct process *proc)
{
    Uint *hp;
    Uint size;
    Eterm res;
#ifdef DEBUG
    Uint *endp;
#endif

    erts_smp_proc_unlock(proc, ERTS_PROC_LOCK_MAIN);
    erts_smp_block_system(0);
    /* No need to lock any thing since we are alone... */

    if (references_atoms_need_init) {
	INIT_AM(heap);
	INIT_AM(link);
	INIT_AM(monitor);
	INIT_AM(process);
	INIT_AM(port);
	INIT_AM(ets);
	INIT_AM(binary);
	INIT_AM(match_spec);
	INIT_AM(control);
	INIT_AM(dist);
	INIT_AM(node);
	INIT_AM(dist_references);
	INIT_AM(node_references);
	INIT_AM(timer);
	INIT_AM(system);
#ifdef HYBRID
	INIT_AM(processes);
#endif
	references_atoms_need_init = 0;
    }

    setup_reference_table();

    /* Get term size */
    size = 0;
    (void) reference_table_term(NULL, &size);

    hp = HAlloc(proc, size);
#ifdef DEBUG
    ASSERT(size > 0);
    endp = hp + size;
#endif

    /* Write term */
    res = reference_table_term(&hp, NULL);

    ASSERT(endp == hp);

    delete_reference_table();

    erts_smp_release_system();
    erts_smp_proc_lock(proc, ERTS_PROC_LOCK_MAIN);
    return res;
}

#define HEAP_REF 1
#define LINK_REF 2
#define ETS_REF  3 
#define BIN_REF  4
#define NODE_REF 5
#define CTRL_REF 6
#define MONITOR_REF 7
#define TIMER_REF 8
#define SYSTEM_REF 9

#define INC_TAB_SZ 10

static void
insert_dist_referrer(ReferredDist *referred_dist,
		    int type,
		    Eterm id,
		    Uint creation)
{
    DistReferrer *drp;

    for(drp = referred_dist->referrers; drp; drp = drp->next)
	if(id == drp->id && (type == CTRL_REF
			     || creation == drp->creation))
	    break;

    if(!drp) {
	drp = (DistReferrer *) erts_alloc(ERTS_ALC_T_NC_TMP,
					  sizeof(DistReferrer));
	drp->next = referred_dist->referrers;
	referred_dist->referrers = drp;
	drp->id = id;
	drp->creation = creation;
	drp->node_ref = 0;
	drp->ctrl_ref = 0;
    }

    switch (type) {
    case NODE_REF:	drp->node_ref++;	break;
    case CTRL_REF:	drp->ctrl_ref++;	break;
    default:		ASSERT(0);
    }
}

static void
insert_dist_entry(DistEntry *dist, int type, Eterm id, Uint creation)
{
    ReferredDist *rdp = NULL;
    int i;

    for(i = 0; i < no_referred_dists; i++) {
	if(dist == referred_dists[i].dist) {
	    rdp = &referred_dists[i];
	    break;
	}
    }

    if(!rdp)
	erl_exit(1,
		 "Reference to non-existing distribution table entry found!\n");

    insert_dist_referrer(rdp, type, id, creation);
}

static void
insert_node_referrer(ReferredNode *referred_node, int type, Eterm id)
{
    NodeReferrer *nrp;

    for(nrp = referred_node->referrers; nrp; nrp = nrp->next)
	if(EQ(id, nrp->id))
	    break;

    if(!nrp) {
	nrp = (NodeReferrer *) erts_alloc(ERTS_ALC_T_NC_TMP,
					  sizeof(NodeReferrer));
	nrp->next = referred_node->referrers;
	referred_node->referrers = nrp;
	if(IS_CONST(id))
	    nrp->id = id;
	else {
	    Uint *hp = &nrp->id_heap[0];
	    ASSERT(is_big(id) || is_tuple(id));
	    nrp->id = copy_struct(id, size_object(id), &hp, NULL);
	}
	nrp->heap_ref = 0;
	nrp->link_ref = 0;
	nrp->monitor_ref = 0;
	nrp->ets_ref = 0;
	nrp->bin_ref = 0;
	nrp->timer_ref = 0;
	nrp->system_ref = 0;
    }

    switch (type) {
    case HEAP_REF:	nrp->heap_ref++;	break;
    case LINK_REF:	nrp->link_ref++;	break;
    case ETS_REF:	nrp->ets_ref++;		break;
    case BIN_REF:	nrp->bin_ref++;		break;
    case MONITOR_REF:   nrp->monitor_ref++;     break;
    case TIMER_REF:	nrp->timer_ref++;	break;
    case SYSTEM_REF:	nrp->system_ref++;	break;
    default:		ASSERT(0);
    }
}

static void
insert_node(ErlNode *node, int type, Eterm id)
{
    int i;
    ReferredNode *rnp = NULL;
    for(i = 0; i < no_referred_nodes; i++) {
	if(node == referred_nodes[i].node) {
	    rnp = &referred_nodes[i];
	    break;
	}
    }

    if (!rnp)
	erl_exit(1, "Reference to non-existing node table entry found!\n");

    insert_node_referrer(rnp, type, id);
}

static void
insert_erl_node(void *venp, void *unused)
{
    ErlNode *enp = (ErlNode *) venp;

    insert_dist_entry(enp->dist_entry, NODE_REF, enp->sysname, enp->creation);
}

struct insert_offheap2_arg {
    int type;
    Eterm id;
};

static void insert_offheap(ErlOffHeap *, int, Eterm);

static void
insert_offheap2(ErlOffHeap *oh, void *arg) 
{
    struct insert_offheap2_arg *a = (struct insert_offheap2_arg *) arg;
    insert_offheap(oh, a->type, a->id);
}

static void
insert_offheap(ErlOffHeap *oh, int type, Eterm id)
{
    if(oh->externals) {
	ExternalThing *etp = oh->externals;
	while (etp) {
	    insert_node(etp->node, type, id);
	    etp = etp->next;
	}
    }

    if(oh->mso) {