nxt_port_hash.c

/*
 * Copyright (C) Max Romanov
 * Copyright (C) NGINX, Inc.
 */

#include <nxt_port_hash.h>


// Explicitly using 32 bit types to avoid possible alignment.
typedef struct {
    int32_t   pid;
    uint32_t  port_id;
} nxt_pid_port_id_t;


static nxt_int_t
nxt_port_hash_test(nxt_lvlhsh_query_t *lhq, void *data)
{
    nxt_port_t         *port;
    nxt_pid_port_id_t  *pid_port_id;

    port = data;
    pid_port_id = (nxt_pid_port_id_t *) lhq->key.start;

    if (lhq->key.length == sizeof(nxt_pid_port_id_t)
        && pid_port_id->pid == port->pid
        && pid_port_id->port_id == port->id)
    {
        return NXT_OK;
    }

    return NXT_DECLINED;
}

static const nxt_lvlhsh_proto_t  lvlhsh_ports_proto  nxt_aligned(64) = {
    NXT_LVLHSH_DEFAULT,
    nxt_port_hash_test,
    nxt_lvlhsh_alloc,
    nxt_lvlhsh_free,
};


nxt_port_t *
nxt_port_hash_retrieve(nxt_lvlhsh_t *port_hash)
{
    return nxt_lvlhsh_retrieve(port_hash, &lvlhsh_ports_proto, NULL);
}


nxt_inline void
nxt_port_hash_lhq(nxt_lvlhsh_query_t *lhq, nxt_pid_port_id_t *pid_port)
{
    lhq->key_hash = nxt_murmur_hash2(pid_port, sizeof(nxt_pid_port_id_t));
    lhq->key.length = sizeof(nxt_pid_port_id_t);
    lhq->key.start = (u_char *) pid_port;
    lhq->proto = &lvlhsh_ports_proto;
    lhq->pool = NULL;
}


nxt_int_t
nxt_port_hash_add(nxt_lvlhsh_t *port_hash, nxt_port_t *port)
{
    nxt_int_t           res;
    nxt_pid_port_id_t   pid_port;
    nxt_lvlhsh_query_t  lhq;

    pid_port.pid = port->pid;
    pid_port.port_id = port->id;

    nxt_port_hash_lhq(&lhq, &pid_port);
    lhq.replace = 0;
    lhq.value = port;

    res = nxt_lvlhsh_insert(port_hash, &lhq);

    switch (res) {

    case NXT_OK:
        break;

    default:
        nxt_thread_log_error(NXT_LOG_WARN, "port #%d for pid %PI add failed",
                             port->id, port->pid);
        break;
    }

    return res;
}


nxt_int_t
nxt_port_hash_remove(nxt_lvlhsh_t *port_hash, nxt_port_t *port)
{
    nxt_int_t           res;
    nxt_pid_port_id_t   pid_port;
    nxt_lvlhsh_query_t  lhq;

    pid_port.pid = port->pid;
    pid_port.port_id = port->id;

    nxt_port_hash_lhq(&lhq, &pid_port);

    res = nxt_lvlhsh_delete(port_hash, &lhq);

    switch (res) {

    case NXT_OK:
        break;

    default:
        nxt_thread_log_error(NXT_LOG_WARN, "port #%d for pid %PI remove failed",
                             port->id, port->pid);
        break;
    }

    return res;
}


nxt_port_t *
nxt_port_hash_find(nxt_lvlhsh_t *port_hash, nxt_pid_t pid,
    nxt_port_id_t port_id)
{
    nxt_pid_port_id_t   pid_port;
    nxt_lvlhsh_query_t  lhq;

    pid_port.pid = pid;
    pid_port.port_id = port_id;

    nxt_port_hash_lhq(&lhq, &pid_port);

    if (nxt_lvlhsh_find(port_hash, &lhq) == NXT_OK) {
        nxt_thread_log_debug("process port (%PI, %d) found", pid, port_id);
        return lhq.value;
    }

    nxt_thread_log_debug("process port (%PI, %d) not found", pid, port_id);

    return NULL;
}