Exemple #1
0
void libcouchbase_server_buffer_start_packet(libcouchbase_server_t *c,
                                             const void *command_cookie,
                                             ringbuffer_t *buff,
                                             ringbuffer_t *buff_cookie,
                                             const void *data,
                                             libcouchbase_size_t size)
{
    struct libcouchbase_command_data_st ct;
    memset(&ct, 0, sizeof(struct libcouchbase_command_data_st));
    /* @todo we don't want to call gethrtime for each operation, */
    /* so I need to pass it down the chain so that a large */
    /* multiget can reuse the same timer... */
    ct.start = gethrtime();
    ct.cookie = command_cookie;

    if (ringbuffer_get_nbytes(buff_cookie) == 0) {
        c->next_timeout = ct.start;
        libcouchbase_update_timer(c->instance);
    }

    if (!ringbuffer_ensure_capacity(buff, size) ||
            !ringbuffer_ensure_capacity(&c->cmd_log, size) ||
            !ringbuffer_ensure_capacity(buff_cookie, sizeof(ct)) ||
            ringbuffer_write(buff, data, size) != size ||
            ringbuffer_write(&c->cmd_log, data, size) != size ||
            ringbuffer_write(buff_cookie, &ct, sizeof(ct)) != sizeof(ct)) {
        abort();
    }
}
Exemple #2
0
void libcouchbase_server_buffer_write_packet(libcouchbase_server_t *c,
                                             ringbuffer_t *buff,
                                             const void *data,
                                             libcouchbase_size_t size)
{
    (void)c;
    if (!ringbuffer_ensure_capacity(buff, size) ||
            !ringbuffer_ensure_capacity(&c->cmd_log, size) ||
            ringbuffer_write(buff, data, size) != size ||
            ringbuffer_write(&c->cmd_log, data, size) != size) {
        abort();
    }
}
Exemple #3
0
static void request_config(cccp_provider *cccp)
{
    protocol_binary_request_set_cluster_config req;
    lcb_connection_t conn = &cccp->connection;
    ringbuffer_t *buf = conn->output;

    memset(&req, 0, sizeof(req));
    req.message.header.request.magic = PROTOCOL_BINARY_REQ;
    req.message.header.request.opcode = CMD_GET_CLUSTER_CONFIG;
    req.message.header.request.opaque = 0xF00D;

    if (!buf) {
        if ((buf = calloc(1, sizeof(*buf))) == NULL) {
            mcio_error(cccp, LCB_CLIENT_ENOMEM);
            return;
        }
        conn->output = buf;
    }

    if (!ringbuffer_ensure_capacity(buf, sizeof(req.bytes))) {
        mcio_error(cccp, LCB_CLIENT_ENOMEM);
    }

    ringbuffer_write(buf, req.bytes, sizeof(req.bytes));
    lcb_sockrw_set_want(conn, LCB_WRITE_EVENT, 1);
    lcb_sockrw_apply_want(conn);
    lcb_timer_rearm(cccp->timer, PROVIDER_SETTING(&cccp->base,
                                                  config_node_timeout));
}
Exemple #4
0
int ringbuffer_memcpy(ringbuffer_t *dst, ringbuffer_t *src,
                      lcb_size_t nbytes)
{
    ringbuffer_t copy = *src;
    struct lcb_iovec_st iov[2];
    int ii = 0;
    lcb_size_t towrite = nbytes;
    lcb_size_t toread, nb;

    if (nbytes > ringbuffer_get_nbytes(src)) {
        /* EINVAL */
        return -1;
    }

    if (!ringbuffer_ensure_capacity(dst, nbytes)) {
        /* Failed to allocate space */
        return -1;
    }

    ringbuffer_get_iov(dst, RINGBUFFER_WRITE, iov);
    toread = minimum(iov[ii].iov_len, nbytes);
    do {
        assert(ii < 2);
        nb = ringbuffer_read(&copy, iov[ii].iov_base, toread);
        toread -= nb;
        towrite -= nb;
        ++ii;
    } while (towrite > 0);
    ringbuffer_produced(dst, nbytes);
    return 0;
}
Exemple #5
0
void
lcbio_ctx_put(lcbio_CTX *ctx, const void *buf, unsigned nbuf)
{
    lcbio__EASYRB *erb = ctx->output;

    if (!erb) {
        ctx->output = erb = calloc(1, sizeof(*ctx->output));

        if (!erb) {
            lcbio_ctx_senderr(ctx, LCB_CLIENT_ENOMEM);
            return;
        }

        erb->parent = ctx;

        if (!ringbuffer_initialize(&erb->rb, nbuf)) {
            lcbio_ctx_senderr(ctx, LCB_CLIENT_ENOMEM);
            return;
        }
    }

    if (!ringbuffer_ensure_capacity(&erb->rb, nbuf)) {
        lcbio_ctx_senderr(ctx, LCB_CLIENT_ENOMEM);
        return;
    }

    ringbuffer_write(&erb->rb, buf, nbuf);
}
Exemple #6
0
static int do_fill_input_buffer(libcouchbase_server_t *c)
{
    struct libcouchbase_iovec_st iov[2];
    libcouchbase_ssize_t nr;

    if (!ringbuffer_ensure_capacity(&c->input, 8192)) {
        libcouchbase_error_handler(c->instance, LIBCOUCHBASE_CLIENT_ENOMEM, NULL);
        return -1;
    }

    ringbuffer_get_iov(&c->input, RINGBUFFER_WRITE, iov);

    nr = c->instance->io->recvv(c->instance->io, c->sock, iov, 2);
    if (nr == -1) {
        switch (c->instance->io->error) {
        case EINTR:
            break;
        case EWOULDBLOCK:
            return 0;
        default:
            libcouchbase_failout_server(c, LIBCOUCHBASE_NETWORK_ERROR);
            return -1;
        }
    } else if (nr == 0) {
        assert((iov[0].iov_len + iov[1].iov_len) != 0);
        /* TODO stash error message somewhere
         * "Connection closed... we should resend to other nodes or reconnect!!" */
        libcouchbase_failout_server(c, LIBCOUCHBASE_NETWORK_ERROR);
        return -1;
    } else {
        ringbuffer_produced(&c->input, (libcouchbase_size_t)nr);
    }

    return 1;
}
Exemple #7
0
lcb_size_t ringbuffer_strcat(ringbuffer_t *buffer, const char *str)
{
    lcb_size_t len = strlen(str);
    if (!ringbuffer_ensure_capacity(buffer, len)) {
        return 0;
    }
    return ringbuffer_write(buffer, str, len);
}
Exemple #8
0
void libcouchbase_server_buffer_retry_packet(libcouchbase_server_t *c,
                                             struct libcouchbase_command_data_st *ct,
                                             ringbuffer_t *buff,
                                             ringbuffer_t *buff_cookie,
                                             const void *data,
                                             libcouchbase_size_t size)
{
    libcouchbase_size_t ct_size = sizeof(struct libcouchbase_command_data_st);
    if (ringbuffer_get_nbytes(buff_cookie) == 0) {
        c->next_timeout = ct->start;
        libcouchbase_update_timer(c->instance);
    }

    if (!ringbuffer_ensure_capacity(buff, size) ||
            !ringbuffer_ensure_capacity(&c->cmd_log, size) ||
            !ringbuffer_ensure_capacity(buff_cookie, ct_size) ||
            ringbuffer_write(buff, data, size) != size ||
            ringbuffer_write(&c->cmd_log, data, size) != size ||
            ringbuffer_write(buff_cookie, ct, ct_size) != ct_size) {
        abort();
    }
}
Exemple #9
0
int ringbuffer_append(ringbuffer_t *src, ringbuffer_t *dest)
{
    char buffer[1024];
    lcb_size_t nr, nw;

    while ((nr = ringbuffer_read(src, buffer, sizeof(buffer))) != 0) {
        lcb_assert(ringbuffer_ensure_capacity(dest, nr));
        nw = ringbuffer_write(dest, buffer, nr);
        lcb_assert(nw == nr);
    }

    return 1;
}
/**
 * Request a read of data into the buffer
 * @param conn the connection object
 * @param buf a ringbuffer structure. If the read request is successful,
 * the ringbuffer is destroyed. Its allocated data is owned by the IO plugin
 * for the duration of the operation. It may be restored via
 * ringbuffer_take_buffer once the operation has finished.
 */
lcb_sockrw_status_t lcb_sockrw_v1_start_read(lcb_connection_t conn,
                                             ringbuffer_t **buf,
                                             lcb_io_read_cb callback,
                                             lcb_io_error_cb error_callback)
{
    int ret;
    lcb_io_opt_t io;
    struct lcb_buf_info *bi = &conn->sockptr->read_buffer;

    if (conn->sockptr->is_reading) {
        return LCB_SOCKRW_PENDING;
    }

    ringbuffer_ensure_capacity(*buf,
                               conn->settings ? conn->settings->rbufsize :
                               LCB_DEFAULT_RBUFSIZE);
    ringbuffer_get_iov(*buf, RINGBUFFER_WRITE, bi->iov);

    lcb_assert(bi->ringbuffer == NULL);
    lcb_assert(bi->root == NULL);

    bi->ringbuffer = *buf;
    bi->root = bi->ringbuffer->root;

    *buf = NULL;


    io = conn->io;
    ret = io->v.v1.start_read(io, conn->sockptr, callback);

    if (ret == 0) {
        conn->sockptr->is_reading = 1;
        return LCB_SOCKRW_PENDING;

    } else {
        *buf = bi->ringbuffer;
        memset(bi, 0, sizeof(*bi));
        if (error_callback) {
            io->v.v1.send_error(io, conn->sockptr, error_callback);
        }
    }

    return LCB_SOCKRW_IO_ERROR;
}
lcb_sockrw_status_t lcb_sockrw_v0_read(lcb_connection_t conn, ringbuffer_t *buf)
{
    struct lcb_iovec_st iov[2];
    lcb_ssize_t nr;
    lcb_io_opt_t io = conn->io;

    if (!ringbuffer_ensure_capacity(buf,
                                    conn->settings ? conn->settings->rbufsize :
                                    LCB_DEFAULT_RBUFSIZE)) {
        return LCB_SOCKRW_GENERIC_ERROR;
    }

    ringbuffer_get_iov(buf, RINGBUFFER_WRITE, iov);

    nr = io->v.v0.recvv(io, conn->sockfd, iov, 2);
    if (nr == -1) {
        switch (io->v.v0.error) {
        case EINTR:
            break;
        case EWOULDBLOCK:
#ifdef USE_EAGAIN
        case EAGAIN:
#endif
            return LCB_SOCKRW_WOULDBLOCK;
        default:
            return LCB_SOCKRW_IO_ERROR;
            return -1;
        }

    } else if (nr == 0) {
        lcb_assert((iov[0].iov_len + iov[1].iov_len) != 0);
        /* TODO stash error message somewhere
         * "Connection closed... we should resend to other nodes or reconnect!!" */
        return LCB_SOCKRW_SHUTDOWN;

    } else {
        ringbuffer_produced(buf, (lcb_size_t)nr);
    }

    return LCB_SOCKRW_READ;
}
Exemple #12
0
int ringbuffer_append(ringbuffer_t *src, ringbuffer_t *dest)
{
    char buffer[1024];
    lcb_size_t nr, nw;

    while ((nr = ringbuffer_read(src, buffer,
                                 sizeof(buffer))) != 0) {
        if (!ringbuffer_ensure_capacity(dest, nr)) {
            abort();
            return 0;
        }

        nw = ringbuffer_write(dest, buffer, nr);
        if (nw != nr) {
            abort();
            return 0;
        }
    }

    return 1;
}
Exemple #13
0
/**
 * Extended version of observe command. This allows us to service
 * various forms of higher level operations which use observe in one way
 * or another
 */
lcb_error_t lcb_observe_ex(lcb_t instance,
                           const void *command_cookie,
                           lcb_size_t num,
                           const void *const *items,
                           lcb_observe_type_t type)
{
    lcb_size_t ii;
    lcb_size_t maxix;
    lcb_uint32_t opaque;
    struct lcb_command_data_st ct;
    struct observe_requests_st reqs;

    memset(&reqs, 0, sizeof(reqs));

    if (instance->type != LCB_TYPE_BUCKET) {
        return lcb_synchandler_return(instance, LCB_EBADHANDLE);
    }

    if (instance->config.handle == NULL) {
        return lcb_synchandler_return(instance, LCB_CLIENT_ETMPFAIL);
    }

    if (instance->config.dist_type != VBUCKET_DISTRIBUTION_VBUCKET) {
        return lcb_synchandler_return(instance, LCB_NOT_SUPPORTED);
    }

    opaque = ++instance->seqno;
    ct.cookie = command_cookie;
    maxix = instance->config.nreplicas;

    if (type == LCB_OBSERVE_TYPE_CHECK) {
        maxix = 0;

    } else {
        if (type == LCB_OBSERVE_TYPE_DURABILITY) {
            ct.flags = LCB_CMD_F_OBS_DURABILITY | LCB_CMD_F_OBS_BCAST;

        } else {
            ct.flags = LCB_CMD_F_OBS_BCAST;
        }
    }

    reqs.nrequests = instance->nservers;
    reqs.requests = calloc(reqs.nrequests, sizeof(*reqs.requests));

    for (ii = 0; ii < num; ii++) {
        const void *key, *hashkey;
        lcb_size_t nkey, nhashkey;
        int vbid, jj;

        if (type == LCB_OBSERVE_TYPE_DURABILITY) {
            const lcb_durability_entry_t *ent = items[ii];
            key = ent->request.v.v0.key;
            nkey = ent->request.v.v0.nkey;
            hashkey = ent->request.v.v0.hashkey;
            nhashkey = ent->request.v.v0.nhashkey;
        } else {
            const lcb_observe_cmd_t *ocmd = items[ii];
            key = ocmd->v.v0.key;
            nkey = ocmd->v.v0.nkey;
            hashkey = ocmd->v.v0.hashkey;
            nhashkey = ocmd->v.v0.nhashkey;
        }
        if (!nhashkey) {
            hashkey = key;
            nhashkey = nkey;
        }

        vbid = vbucket_get_vbucket_by_key(instance->config.handle,
                                          hashkey, nhashkey);

        for (jj = -1; jj < (int)maxix; jj++) {
            struct observe_st *rr;

            int idx = vbucket_get_replica(instance->config.handle,
                                          vbid, jj);

            if (idx < 0 || idx > (int)instance->nservers) {
                if (jj == -1) {
                    destroy_requests(&reqs);
                    return lcb_synchandler_return(instance, LCB_NO_MATCHING_SERVER);
                }
                continue;
            }
            lcb_assert(idx < (int)reqs.nrequests);
            rr = reqs.requests + idx;

            if (!rr->allocated) {
                if (!init_request(rr)) {
                    destroy_requests(&reqs);
                    return lcb_synchandler_return(instance, LCB_CLIENT_ENOMEM);
                }
            }

            {
                lcb_uint16_t vb = htons((lcb_uint16_t)vbid);
                lcb_uint16_t len = htons((lcb_uint16_t)nkey);

                rr->packet.message.header.request.magic = PROTOCOL_BINARY_REQ;
                rr->packet.message.header.request.opcode = CMD_OBSERVE;
                rr->packet.message.header.request.datatype = PROTOCOL_BINARY_RAW_BYTES;
                rr->packet.message.header.request.opaque = opaque;

                ringbuffer_ensure_capacity(&rr->body,
                                           sizeof(vb) + sizeof(len) + nkey);
                rr->nbody += ringbuffer_write(&rr->body, &vb, sizeof(vb));
                rr->nbody += ringbuffer_write(&rr->body, &len, sizeof(len));
                rr->nbody += ringbuffer_write(&rr->body, key, nkey);
            }
        }
    }

    for (ii = 0; ii < reqs.nrequests; ii++) {
        struct observe_st *rr = reqs.requests + ii;
        struct lcb_server_st *server = instance->servers + ii;
        char *tmp;

        if (!rr->allocated) {
            continue;
        }

        rr->packet.message.header.request.bodylen = ntohl((lcb_uint32_t)rr->nbody);
        ct.start = gethrtime();

        lcb_server_start_packet_ct(server, &ct, rr->packet.bytes,
                                   sizeof(rr->packet.bytes));

        if (ringbuffer_is_continous(&rr->body, RINGBUFFER_READ, rr->nbody)) {
            tmp = ringbuffer_get_read_head(&rr->body);
            TRACE_OBSERVE_BEGIN(&rr->packet, server->authority, tmp, rr->nbody);
            lcb_server_write_packet(server, tmp, rr->nbody);
        } else {
            tmp = malloc(ringbuffer_get_nbytes(&rr->body));
            if (!tmp) {
                /* FIXME by this time some of requests might be scheduled */
                destroy_requests(&reqs);
                return lcb_synchandler_return(instance, LCB_CLIENT_ENOMEM);
            } else {
                ringbuffer_read(&rr->body, tmp, rr->nbody);
                TRACE_OBSERVE_BEGIN(&rr->packet, server->authority, tmp, rr->nbody);
                lcb_server_write_packet(server, tmp, rr->nbody);
            }
        }
        lcb_server_end_packet(server);
        lcb_server_send_packets(server);
    }

    destroy_requests(&reqs);
    return lcb_synchandler_return(instance, LCB_SUCCESS);
}
Exemple #14
0
LIBCOUCHBASE_API
lcb_error_t lcb_observe(lcb_t instance,
                        const void *command_cookie,
                        lcb_size_t num,
                        const lcb_observe_cmd_t *const *items)
{
    int vbid, idx, jj;
    lcb_size_t ii;
    lcb_uint32_t opaque;
    struct observe_st *requests;

    /* we need a vbucket config before we can start getting data.. */
    if (instance->vbucket_config == NULL) {
        switch (instance->type) {
        case LCB_TYPE_CLUSTER:
            return lcb_synchandler_return(instance, LCB_EBADHANDLE);
        case LCB_TYPE_BUCKET:
        default:
            return lcb_synchandler_return(instance, LCB_CLIENT_ETMPFAIL);
        }
    }

    if (instance->dist_type != VBUCKET_DISTRIBUTION_VBUCKET) {
        return lcb_synchandler_return(instance, LCB_NOT_SUPPORTED);
    }

    /* the list of pointers to body buffers for each server */
    requests = calloc(instance->nservers, sizeof(struct observe_st));
    opaque = ++instance->seqno;
    for (ii = 0; ii < num; ++ii) {
        const void *key = items[ii]->v.v0.key;
        lcb_size_t nkey = items[ii]->v.v0.nkey;
        const void *hashkey = items[ii]->v.v0.hashkey;
        lcb_size_t nhashkey = items[ii]->v.v0.nhashkey;

        if (nhashkey == 0) {
            hashkey = key;
            nhashkey = nkey;
        }

        vbid = vbucket_get_vbucket_by_key(instance->vbucket_config, hashkey,
                                          nhashkey);
        for (jj = -1; jj < instance->nreplicas; ++jj) {
            struct observe_st *rr;
            /* it will increment jj to get server index, so (-1 + 1) = 0 (master) */
            idx = vbucket_get_replica(instance->vbucket_config, vbid, jj);
            if ((idx < 0 || idx > (int)instance->nservers)) {
                /* the config says that there is no server yet at that position (-1) */
                if (jj == -1) {
                    /* master node must be available */
                    destroy_requests(requests, instance->nservers);
                    return lcb_synchandler_return(instance, LCB_NETWORK_ERROR);
                } else {
                    continue;
                }
            }
            rr = requests + idx;
            if (!rr->allocated) {
                if (!init_request(rr)) {
                    destroy_requests(requests, instance->nservers);
                    return lcb_synchandler_return(instance, LCB_CLIENT_ENOMEM);
                }
                rr->req.message.header.request.magic = PROTOCOL_BINARY_REQ;
                rr->req.message.header.request.opcode = CMD_OBSERVE;
                rr->req.message.header.request.datatype = PROTOCOL_BINARY_RAW_BYTES;
                rr->req.message.header.request.opaque = opaque;
            }

            {
                lcb_uint16_t vb = htons((lcb_uint16_t)vbid);
                lcb_uint16_t len = htons((lcb_uint16_t)nkey);
                ringbuffer_ensure_capacity(&rr->body, sizeof(vb) + sizeof(len) + nkey);
                rr->nbody += ringbuffer_write(&rr->body, &vb, sizeof(vb));
                rr->nbody += ringbuffer_write(&rr->body, &len, sizeof(len));
                rr->nbody += ringbuffer_write(&rr->body, key, nkey);
            }
        }
    }

    for (ii = 0; ii < instance->nservers; ++ii) {
        struct observe_st *rr = requests + ii;
        lcb_server_t *server = instance->servers + ii;

        if (rr->allocated) {
            char *tmp;
            rr->req.message.header.request.bodylen = ntohl((lcb_uint32_t)rr->nbody);
            lcb_server_start_packet(server, command_cookie, rr->req.bytes, sizeof(rr->req.bytes));
            if (ringbuffer_is_continous(&rr->body, RINGBUFFER_READ, rr->nbody)) {
                tmp = ringbuffer_get_read_head(&rr->body);
                TRACE_OBSERVE_BEGIN(&rr->req, server->authority, tmp, rr->nbody);
                lcb_server_write_packet(server, tmp, rr->nbody);
            } else {
                tmp = malloc(ringbuffer_get_nbytes(&rr->body));
                if (!tmp) {
                    /* FIXME by this time some of requests might be scheduled */
                    destroy_requests(requests, instance->nservers);
                    return lcb_synchandler_return(instance, LCB_CLIENT_ENOMEM);
                } else {
                    ringbuffer_read(&rr->body, tmp, rr->nbody);
                    TRACE_OBSERVE_BEGIN(&rr->req, server->authority, tmp, rr->nbody);
                    lcb_server_write_packet(server, tmp, rr->nbody);
                }
            }
            lcb_server_end_packet(server);
            lcb_server_send_packets(server);
        }
    }

    destroy_requests(requests, instance->nservers);
    return lcb_synchandler_return(instance, LCB_SUCCESS);
}
Exemple #15
0
static lcb_error_t
obs_ctxadd(lcb_MULTICMD_CTX *mctx, const lcb_CMDOBSERVE *cmd)
{
    const void *hk;
    lcb_SIZE nhk;
    int vbid;
    unsigned maxix;
    int ii;
    OBSERVECTX *ctx = CTX_FROM_MULTI(mctx);
    lcb_t instance = ctx->instance;
    mc_CMDQUEUE *cq = &instance->cmdq;

    if (LCB_KEYBUF_IS_EMPTY(&cmd->key)) {
        return LCB_EMPTY_KEY;
    }

    if (cq->config == NULL) {
        return LCB_CLIENT_ETMPFAIL;
    }

    if (instance->dist_type != LCBVB_DIST_VBUCKET) {
        return LCB_NOT_SUPPORTED;
    }

    mcreq_extract_hashkey(&cmd->key, &cmd->hashkey, 24, &hk, &nhk);
    vbid = lcbvb_k2vb(cq->config, hk, nhk);
    maxix = LCBVB_NREPLICAS(cq->config);

    for (ii = -1; ii < (int)maxix; ++ii) {
        struct observe_st *rr;
        lcb_U16 vb16, klen16;
        int ix;

        if (ii == -1) {
            ix = lcbvb_vbmaster(cq->config, vbid);
            if (ix < 0) {
                return LCB_NO_MATCHING_SERVER;
            }
        } else {
            ix = lcbvb_vbreplica(cq->config, vbid, ii);
            if (ix < 0) {
                continue;
            }
        }

        lcb_assert(ix < (int)ctx->nrequests);
        rr = ctx->requests + ix;
        if (!rr->allocated) {
            if (!init_request(rr)) {
                return LCB_CLIENT_ENOMEM;
            }
        }

        vb16 = htons((lcb_U16)vbid);
        klen16 = htons((lcb_U16)cmd->key.contig.nbytes);
        ringbuffer_ensure_capacity(&rr->body, sizeof(vb16) + sizeof(klen16));
        ringbuffer_write(&rr->body, &vb16, sizeof vb16);
        ringbuffer_write(&rr->body, &klen16, sizeof klen16);
        ringbuffer_write(&rr->body, cmd->key.contig.bytes, cmd->key.contig.nbytes);
        ctx->remaining++;
        if (cmd->cmdflags & LCB_CMDOBSERVE_F_MASTER_ONLY) {
            break;
        }
    }
    return LCB_SUCCESS;
}
Exemple #16
0
static libcouchbase_error_t create_memcached(const struct libcouchbase_memcached_st *user,
                                             VBUCKET_CONFIG_HANDLE vbconfig)
{
    ringbuffer_t buffer;
    char *copy = strdup(user->serverlist);
    char head[1024];
    int first;
    char *ptr = copy;
    int fail;
    libcouchbase_ssize_t offset = 0;

    if (copy == NULL) {
        return LIBCOUCHBASE_CLIENT_ENOMEM;
    }

    if (ringbuffer_initialize(&buffer, 1024) == -1) {
        free(copy);
        return LIBCOUCHBASE_CLIENT_ENOMEM;
    }

    head[0] = '\0';
    offset += snprintf(head + offset, sizeof(head) - offset, "%s", "{");
    offset += snprintf(head + offset, sizeof(head) - offset, "%s",
                       "\"bucketType\":\"memcached\",");
    offset += snprintf(head + offset, sizeof(head) - offset, "%s",
                       "\"nodeLocator\":\"ketama\",");
    if (user->username != NULL) {
        offset += snprintf(head + offset, sizeof(head) - offset, "%s",
                           "\"authType\":\"sasl\",");
        offset += snprintf(head + offset, sizeof(head) - offset, "%s",
                           "\"name\":\"");
        offset += snprintf(head + offset, sizeof(head) - offset, "%s",
                           user->username);
        offset += snprintf(head + offset, sizeof(head) - offset, "%s", "\",");
        if (user->password != NULL) {
            offset += snprintf(head + offset, sizeof(head) - offset, "%s",
                               "\"saslPassword\":\"");
            offset += snprintf(head + offset, sizeof(head) - offset, "%s",
                               user->password);
            offset += snprintf(head + offset, sizeof(head) - offset, "%s",
                               "\",");
        }
    }

    offset += snprintf(head + offset, sizeof(head) - offset, "%s",
                       "\"nodes\": [");
    ringbuffer_write(&buffer, head, strlen(head));

    /* Let's add the hosts... */
    first = 1;
    do {
        char *tok;
        char *next = strchr(ptr, ';');
        const char *port = "11211";
        libcouchbase_ssize_t length;

        if (next != NULL) {
            *next = '\0';
        }

        tok = strchr(ptr, ':');
        if (tok != NULL) {
            *tok = '\0';
            port = tok + 1;
            if ((tok = strchr(ptr, ':')) != NULL) {
                *tok = '\0'; /* Remove weight for now */
            }
        }

        length = snprintf(head, sizeof(head),
                          "%c{\"hostname\":\"%s\",\"ports\":{\"direct\":%s}}",
                          first ? ' ' : ',', ptr, port);
        first = 0;

        if (ringbuffer_ensure_capacity(&buffer, length) == -1) {
            free(copy);
            return LIBCOUCHBASE_CLIENT_ENOMEM;
        }

        ringbuffer_write(&buffer, head, length);

        if (next != NULL) {
            ptr = next + 1;
        } else {
            ptr = NULL;
        }
    } while (ptr != NULL);

    if (ringbuffer_ensure_capacity(&buffer, 3) == -1) {
        free(copy);
        return LIBCOUCHBASE_CLIENT_ENOMEM;
    }

    ringbuffer_write(&buffer, "]}", 3); /* Include '\0' */

    /* Now let's parse the config! */
    fail = vbucket_config_parse(vbconfig, LIBVBUCKET_SOURCE_MEMORY,
                                (char *)ringbuffer_get_read_head(&buffer));
    free(copy);
    ringbuffer_destruct(&buffer);

    if (fail) {
        /* Hmm... internal error! */
        return LIBCOUCHBASE_EINTERNAL;
    }

    return LIBCOUCHBASE_SUCCESS;
}