Function win_endpoint_refresh_rendezvous

src/daemon/ipc.c:4662–4722

}

static win_rendezvous_status_t win_endpoint_refresh_rendezvous(
    const cbm_daemon_ipc_endpoint_t *endpoint) {
    if (!endpoint || !endpoint->user_sid || endpoint->user_sid_length == 0) {
        return WIN_RENDEZVOUS_ERROR;
    }
    cbm_private_lock_directory_t *directory = NULL;
    cbm_private_file_lock_t *record_lock = NULL;
    cbm_private_file_lock_status_t directory_status =
        cbm_daemon_ipc_private_lock_directory_new(endpoint, &directory);
    if (directory_status != CBM_PRIVATE_FILE_LOCK_OK) {
        win_endpoint_generation_invalidate(endpoint);
        return WIN_RENDEZVOUS_ERROR;
    }
    cbm_private_file_lock_status_t lock_status = cbm_private_file_lock_try_acquire(
        directory, CBM_DAEMON_IPC_WINDOWS_RENDEZVOUS_FILE, CBM_PRIVATE_FILE_LOCK_SH, &record_lock);
    if (lock_status != CBM_PRIVATE_FILE_LOCK_OK) {
        win_private_lock_release_complete(&record_lock);
        cbm_private_lock_directory_close(directory);
        win_endpoint_generation_invalidate(endpoint);
        return lock_status == CBM_PRIVATE_FILE_LOCK_BUSY ? WIN_RENDEZVOUS_BUSY
                                                         : WIN_RENDEZVOUS_ERROR;
    }

    uint8_t record[CBM_DAEMON_IPC_WINDOWS_RENDEZVOUS_RECORD_SIZE];
    size_t record_length = 0;
    cbm_private_file_lock_status_t read_status =
        cbm_private_file_lock_payload_read(record_lock, record, sizeof(record), &record_length);
    uint8_t nonce[CBM_DAEMON_IPC_WINDOWS_NONCE_SIZE];
    char address[CBM_DAEMON_IPC_WINDOWS_NAME_CAP];
    bool decoded =
        read_status == CBM_PRIVATE_FILE_LOCK_OK &&
        cbm_daemon_ipc_windows_rendezvous_record_decode(record, record_length, nonce, address);
    char expected[CBM_DAEMON_IPC_WINDOWS_NAME_CAP];
    bool bound =
        decoded &&
        cbm_daemon_ipc_windows_generation_address(endpoint->user_sid, endpoint->user_sid_length,
                                                  endpoint->instance_key, nonce, expected) &&
        strcmp(expected, address) == 0;
    win_rendezvous_status_t result;
    if (read_status != CBM_PRIVATE_FILE_LOCK_OK) {
        win_endpoint_generation_invalidate(endpoint);
        result = WIN_RENDEZVOUS_ERROR;
    } else if (record_length == 0) {
        win_endpoint_generation_invalidate(endpoint);
        result = WIN_RENDEZVOUS_ABSENT;
    } else if (!bound) {
        win_endpoint_generation_invalidate(endpoint);
        result = WIN_RENDEZVOUS_CORRUPT;
    } else if (!win_endpoint_generation_install(endpoint, address)) {
        win_endpoint_generation_invalidate(endpoint);
        result = WIN_RENDEZVOUS_ERROR;
    } else {
        result = WIN_RENDEZVOUS_VALID;
    }
    /* Keep the record lock through the in-memory snapshot update. Otherwise
     * a reader of generation N could install/invalidate after a startup owner
     * has published generation N+1, regressing this endpoint to stale state. */
    win_private_lock_release_complete(&record_lock);