package rados // #cgo LDFLAGS: -lrados // #include // #include import "C" import "unsafe" import "bytes" // ClusterStat represents Ceph cluster statistics. type ClusterStat struct { Kb uint64 Kb_used uint64 Kb_avail uint64 Num_objects uint64 } // Conn is a connection handle to a Ceph cluster. type Conn struct { cluster C.rados_t } // PingMonitor sends a ping to a monitor and returns the reply. func (c *Conn) PingMonitor(id string) (string, error) { c_id := C.CString(id) defer C.free(unsafe.Pointer(c_id)) var strlen C.size_t var strout *C.char ret := C.rados_ping_monitor(c.cluster, c_id, &strout, &strlen) defer C.rados_buffer_free(strout) if ret == 0 { reply := C.GoStringN(strout, (C.int)(strlen)) return reply, nil } else { return "", RadosError(int(ret)) } } // Connect establishes a connection to a RADOS cluster. It returns an error, // if any. func (c *Conn) Connect() error { ret := C.rados_connect(c.cluster) if ret == 0 { return nil } else { return RadosError(int(ret)) } } // Shutdown disconnects from the cluster. func (c *Conn) Shutdown() { C.rados_shutdown(c.cluster) } // ReadConfigFile configures the connection using a Ceph configuration file. func (c *Conn) ReadConfigFile(path string) error { c_path := C.CString(path) defer C.free(unsafe.Pointer(c_path)) ret := C.rados_conf_read_file(c.cluster, c_path) if ret == 0 { return nil } else { return RadosError(int(ret)) } } // ReadDefaultConfigFile configures the connection using a Ceph configuration // file located at default locations. func (c *Conn) ReadDefaultConfigFile() error { ret := C.rados_conf_read_file(c.cluster, nil) if ret == 0 { return nil } else { return RadosError(int(ret)) } } func (c *Conn) OpenIOContext(pool string) (*IOContext, error) { c_pool := C.CString(pool) defer C.free(unsafe.Pointer(c_pool)) ioctx := &IOContext{} ret := C.rados_ioctx_create(c.cluster, c_pool, &ioctx.ioctx) if ret == 0 { return ioctx, nil } else { return nil, RadosError(int(ret)) } } // ListPools returns the names of all existing pools. func (c *Conn) ListPools() (names []string, err error) { buf := make([]byte, 4096) for { ret := int(C.rados_pool_list(c.cluster, (*C.char)(unsafe.Pointer(&buf[0])), C.size_t(len(buf)))) if ret < 0 { return nil, RadosError(int(ret)) } if ret > len(buf) { buf = make([]byte, ret) continue } tmp := bytes.SplitAfter(buf[:ret-1], []byte{0}) for _, s := range tmp { if len(s) > 0 { name := C.GoString((*C.char)(unsafe.Pointer(&s[0]))) names = append(names, name) } } return names, nil } } // SetConfigOption sets the value of the configuration option identified by // the given name. func (c *Conn) SetConfigOption(option, value string) error { c_opt, c_val := C.CString(option), C.CString(value) defer C.free(unsafe.Pointer(c_opt)) defer C.free(unsafe.Pointer(c_val)) ret := C.rados_conf_set(c.cluster, c_opt, c_val) if ret < 0 { return RadosError(int(ret)) } else { return nil } } // GetConfigOption returns the value of the Ceph configuration option // identified by the given name. func (c *Conn) GetConfigOption(name string) (value string, err error) { buf := make([]byte, 4096) c_name := C.CString(name) defer C.free(unsafe.Pointer(c_name)) ret := int(C.rados_conf_get(c.cluster, c_name, (*C.char)(unsafe.Pointer(&buf[0])), C.size_t(len(buf)))) // FIXME: ret may be -ENAMETOOLONG if the buffer is not large enough. We // can handle this case, but we need a reliable way to test for // -ENAMETOOLONG constant. Will the syscall/Errno stuff in Go help? if ret == 0 { value = C.GoString((*C.char)(unsafe.Pointer(&buf[0]))) return value, nil } else { return "", RadosError(ret) } } // WaitForLatestOSDMap blocks the caller until the latest OSD map has been // retrieved. func (c *Conn) WaitForLatestOSDMap() error { ret := C.rados_wait_for_latest_osdmap(c.cluster) if ret < 0 { return RadosError(int(ret)) } else { return nil } } // GetClusterStat returns statistics about the cluster associated with the // connection. func (c *Conn) GetClusterStats() (stat ClusterStat, err error) { c_stat := C.struct_rados_cluster_stat_t{} ret := C.rados_cluster_stat(c.cluster, &c_stat) if ret < 0 { return ClusterStat{}, RadosError(int(ret)) } else { return ClusterStat{ Kb: uint64(c_stat.kb), Kb_used: uint64(c_stat.kb_used), Kb_avail: uint64(c_stat.kb_avail), Num_objects: uint64(c_stat.num_objects), }, nil } } // ParseCmdLineArgs configures the connection from command line arguments. func (c *Conn) ParseCmdLineArgs(args []string) error { // add an empty element 0 -- Ceph treats the array as the actual contents // of argv and skips the first element (the executable name) argc := C.int(len(args) + 1) argv := make([]*C.char, argc) // make the first element a string just in case it is ever examined argv[0] = C.CString("placeholder") defer C.free(unsafe.Pointer(argv[0])) for i, arg := range args { argv[i+1] = C.CString(arg) defer C.free(unsafe.Pointer(argv[i+1])) } ret := C.rados_conf_parse_argv(c.cluster, argc, &argv[0]) if ret < 0 { return RadosError(int(ret)) } else { return nil } } // ParseDefaultConfigEnv configures the connection from the default Ceph // environment variable(s). func (c *Conn) ParseDefaultConfigEnv() error { ret := C.rados_conf_parse_env(c.cluster, nil) if ret == 0 { return nil } else { return RadosError(int(ret)) } } // GetFSID returns the fsid of the cluster as a hexadecimal string. The fsid // is a unique identifier of an entire Ceph cluster. func (c *Conn) GetFSID() (fsid string, err error) { buf := make([]byte, 37) ret := int(C.rados_cluster_fsid(c.cluster, (*C.char)(unsafe.Pointer(&buf[0])), C.size_t(len(buf)))) // FIXME: the success case isn't documented correctly in librados.h if ret == 36 { fsid = C.GoString((*C.char)(unsafe.Pointer(&buf[0]))) return fsid, nil } else { return "", RadosError(int(ret)) } } // GetInstanceID returns a globally unique identifier for the cluster // connection instance. func (c *Conn) GetInstanceID() uint64 { // FIXME: are there any error cases for this? return uint64(C.rados_get_instance_id(c.cluster)) } // MakePool creates a new pool with default settings. func (c *Conn) MakePool(name string) error { c_name := C.CString(name) defer C.free(unsafe.Pointer(c_name)) ret := int(C.rados_pool_create(c.cluster, c_name)) if ret == 0 { return nil } else { return RadosError(ret) } } // DeletePool deletes a pool and all the data inside the pool. func (c *Conn) DeletePool(name string) error { c_name := C.CString(name) defer C.free(unsafe.Pointer(c_name)) ret := int(C.rados_pool_delete(c.cluster, c_name)) if ret == 0 { return nil } else { return RadosError(ret) } } // MonCommand sends a command to one of the monitors func (c *Conn) MonCommand(args []byte) (buffer []byte, info string, err error) { return c.monCommand(args, nil) } // MonCommand sends a command to one of the monitors, with an input buffer func (c *Conn) MonCommandWithInputBuffer(args, inputBuffer []byte) (buffer []byte, info string, err error) { return c.monCommand(args, inputBuffer) } func (c *Conn) monCommand(args, inputBuffer []byte) (buffer []byte, info string, err error) { argv := C.CString(string(args)) defer C.free(unsafe.Pointer(argv)) var ( outs, outbuf *C.char outslen, outbuflen C.size_t ) inbuf := C.CString(string(inputBuffer)) inbufLen := len(inputBuffer) defer C.free(unsafe.Pointer(inbuf)) ret := C.rados_mon_command(c.cluster, &argv, 1, inbuf, // bulk input (e.g. crush map) C.size_t(inbufLen), // length inbuf &outbuf, // buffer &outbuflen, // buffer length &outs, // status string &outslen) if outslen > 0 { info = C.GoStringN(outs, C.int(outslen)) C.free(unsafe.Pointer(outs)) } if outbuflen > 0 { buffer = C.GoBytes(unsafe.Pointer(outbuf), C.int(outbuflen)) C.free(unsafe.Pointer(outbuf)) } if ret != 0 { err = RadosError(int(ret)) return nil, info, err } return }