multiget.c

APU_DECLARE(apr_status_t)
apr_memcache_multgetp(apr_memcache_t *mc,
                      apr_pool_t *temp_pool,
                      apr_pool_t *data_pool,
                      apr_hash_t *values)
{
    apr_status_t rv;
    apr_memcache_server_t* ms;
    apr_memcache_conn_t* conn;
    apr_uint32_t hash;
    apr_size_t written;
    apr_size_t klen;

    apr_memcache_value_t* value;
    apr_hash_index_t* value_hash_index;

    /* this is a little over aggresive, but beats multiple loops
     * to figure out how long each vector needs to be per-server.
     */
    apr_int32_t veclen = 2 + 2 * apr_hash_count(values) - 1; /* get <key>[<space><key>...]\r\n */
    apr_int32_t i, j;
    apr_int32_t queries_sent;
    apr_int32_t queries_recvd;

    apr_hash_t * server_queries = apr_hash_make(temp_pool);
    struct cache_server_query_t* server_query;
    apr_hash_index_t * query_hash_index;

    apr_pollset_t* pollset;
    const apr_pollfd_t* activefds;
    apr_pollfd_t* pollfds;


    /* build all the queries */
    value_hash_index = apr_hash_first(temp_pool, values);
    while (value_hash_index) {
        void *v;
        apr_hash_this(value_hash_index, NULL, NULL, &v);
        value = v;
        value_hash_index = apr_hash_next(value_hash_index);
        klen = strlen(value->key);

        hash = apr_memcache_hash(mc, value->key, klen);
        ms = apr_memcache_find_server_hash(mc, hash);
        if (ms == NULL) {
            continue;
        }

        server_query = apr_hash_get(server_queries, &ms, sizeof(ms));

        if (!server_query) {
            rv = ms_find_conn(ms, &conn);

            if (rv != APR_SUCCESS) {
                apr_memcache_disable_server(mc, ms);
                value->status = rv;
                continue;
            }

            server_query = apr_pcalloc(temp_pool,sizeof(struct cache_server_query_t));

            apr_hash_set(server_queries, &ms, sizeof(ms), server_query);

            server_query->ms = ms;
            server_query->conn = conn;
            server_query->query_vec = apr_pcalloc(temp_pool, sizeof(struct iovec)*veclen);

            /* set up the first key */
            server_query->query_vec[0].iov_base = MC_GET;
            server_query->query_vec[0].iov_len  = MC_GET_LEN;

            server_query->query_vec[1].iov_base = (void*)(value->key);
            server_query->query_vec[1].iov_len  = klen;

            server_query->query_vec[2].iov_base = MC_EOL;
            server_query->query_vec[2].iov_len  = MC_EOL_LEN;

            server_query->query_vec_count = 3;
        }
        else {
            j = server_query->query_vec_count - 1;

            server_query->query_vec[j].iov_base = MC_WS;
            server_query->query_vec[j].iov_len  = MC_WS_LEN;
            j++;

            server_query->query_vec[j].iov_base = (void*)(value->key);
            server_query->query_vec[j].iov_len  = klen;
            j++;

            server_query->query_vec[j].iov_base = MC_EOL;
            server_query->query_vec[j].iov_len  = MC_EOL_LEN;
            j++;

           server_query->query_vec_count = j;
        }
    }

    /* create polling structures */
    pollfds = apr_pcalloc(temp_pool, apr_hash_count(server_queries) * sizeof(apr_pollfd_t));
    
    rv = apr_pollset_create(&pollset, apr_hash_count(server_queries), temp_pool, 0);

    if (rv != APR_SUCCESS) {
        query_hash_index = apr_hash_first(temp_pool, server_queries);

        while (query_hash_index) {
            void *v;
            apr_hash_this(query_hash_index, NULL, NULL, &v);
            server_query = v;
            query_hash_index = apr_hash_next(query_hash_index);

            mget_conn_result(TRUE, TRUE, rv, mc, server_query->ms, server_query->conn,
                             server_query, values, server_queries);
        }

        return rv;
    }

    /* send all the queries */
    queries_sent = 0;
    query_hash_index = apr_hash_first(temp_pool, server_queries);

    while (query_hash_index) {
        void *v;
        apr_hash_this(query_hash_index, NULL, NULL, &v);
        server_query = v;
        query_hash_index = apr_hash_next(query_hash_index);

        conn = server_query->conn;
        ms = server_query->ms;

        for (i = 0, rv = APR_SUCCESS; i < veclen && rv == APR_SUCCESS; i += APR_MAX_IOVEC_SIZE) {
            rv = apr_socket_sendv(conn->sock, &(server_query->query_vec[i]),
                                  veclen-i>APR_MAX_IOVEC_SIZE ? APR_MAX_IOVEC_SIZE : veclen-i , &written);
        }

        if (rv != APR_SUCCESS) {
            mget_conn_result(FALSE, FALSE, rv, mc, ms, conn,
                             server_query, values, server_queries);
            continue;
        }

        pollfds[queries_sent].desc_type = APR_POLL_SOCKET;
        pollfds[queries_sent].reqevents = APR_POLLIN;
        pollfds[queries_sent].p = temp_pool;
        pollfds[queries_sent].desc.s = conn->sock;
        pollfds[queries_sent].client_data = (void *)server_query;
        apr_pollset_add (pollset, &pollfds[queries_sent]);

        queries_sent++;
    }

    while (queries_sent) {
        rv = apr_pollset_poll(pollset, MULT_GET_TIMEOUT, &queries_recvd, &activefds);

        if (rv != APR_SUCCESS) {
            /* timeout */
            queries_sent = 0;
            continue;
        }
        for (i = 0; i < queries_recvd; i++) {
            server_query = activefds[i].client_data;
            conn = server_query->conn;
            ms = server_query->ms;

           rv = get_server_line(conn);

           if (rv != APR_SUCCESS) {
               apr_pollset_remove (pollset, &activefds[i]);
               mget_conn_result(FALSE, FALSE, rv, mc, ms, conn,
                                server_query, values, server_queries);
               queries_sent--;
               continue;
           }

           if (strncmp(MS_VALUE, conn->buffer, MS_VALUE_LEN) == 0) {
               char *key;
               char *flags;
               char *length;
               char *last;
               char *data;
               apr_size_t len = 0;

               key = apr_strtok(conn->buffer, " ", &last); /* just the VALUE, ignore */
               key = apr_strtok(NULL, " ", &last);
               flags = apr_strtok(NULL, " ", &last);


               length = apr_strtok(NULL, " ", &last);
               if (length) {
                   len = atoi(length);
               }

               value = apr_hash_get(values, key, strlen(key));

               
               if (value) {
                   if (len >= 0)  {
                       apr_bucket_brigade *bbb;
                       apr_bucket *e;
                       
                       /* eat the trailing \r\n */
                       rv = apr_brigade_partition(conn->bb, len+2, &e);
                       
                       if (rv != APR_SUCCESS) {
                           apr_pollset_remove (pollset, &activefds[i]);
                           mget_conn_result(FALSE, FALSE, rv, mc, ms, conn,
                                            server_query, values, server_queries);
                           queries_sent--;
                           continue;
                       }
                       
                       bbb = apr_brigade_split(conn->bb, e);
                       
                       rv = apr_brigade_pflatten(conn->bb, &data, &len, data_pool);
                       
                       if (rv != APR_SUCCESS) {
                           apr_pollset_remove (pollset, &activefds[i]);
                           mget_conn_result(FALSE, FALSE, rv, mc, ms, conn,
                                            server_query, values, server_queries);
                           queries_sent--;
                           continue;
                       }
                       
                       rv = apr_brigade_destroy(conn->bb);
                       if (rv != APR_SUCCESS) {
                           apr_pollset_remove (pollset, &activefds[i]);
                           mget_conn_result(FALSE, FALSE, rv, mc, ms, conn,
                                            server_query, values, server_queries);
                           queries_sent--;
                           continue;
                       }
                       
                       conn->bb = bbb;
                       
                       value->len = len - 2;
                       data[value->len] = '\0';
                       value->data = data;
                   }
                   
                   value->status = rv;
                   value->flags = atoi(flags);
                   
                   /* stay on the server */
                   i--;
                   
               }
               else {
                   /* TODO: Server Sent back a key I didn't ask for or my
                    *       hash is corrupt */
               }
           }
           else if (strncmp(MS_END, conn->buffer, MS_END_LEN) == 0) {
               /* this connection is done */
               apr_pollset_remove (pollset, &activefds[i]);
               ms_release_conn(ms, conn);
               apr_hash_set(server_queries, &ms, sizeof(ms), NULL);
               
               queries_sent--;
           }
           else {
               /* unknown reply? */
               rv = APR_EGENERAL;
           }
           
        } /* /for */
    } /* /while */
    
    query_hash_index = apr_hash_first(temp_pool, server_queries);
    while (query_hash_index) {
        void *v;
        apr_hash_this(query_hash_index, NULL, NULL, &v);
        server_query = v;
        query_hash_index = apr_hash_next(query_hash_index);
        
        conn = server_query->conn;
        ms = server_query->ms;
        
        mget_conn_result(TRUE, (rv == APR_SUCCESS), rv, mc, ms, conn,
                         server_query, values, server_queries);
        continue;
    }
    
    apr_pollset_destroy(pollset);
    apr_pool_clear(temp_pool);
    return APR_SUCCESS;
    
}