go-ceph/rados/rados.go

106 lines
2.7 KiB
Go

package rados
// #cgo LDFLAGS: -lrados
// #include <errno.h>
// #include <stdlib.h>
// #include <rados/librados.h>
import "C"
import (
"fmt"
"runtime"
"unsafe"
)
type RadosError int
func (e RadosError) Error() string {
return fmt.Sprintf("rados: %s", C.GoString(C.strerror(C.int(-e))))
}
var RadosAllNamespaces = C.LIBRADOS_ALL_NSPACES
var RadosErrorNotFound = RadosError(-C.ENOENT)
var RadosErrorPermissionDenied = RadosError(-C.EPERM)
func GetRadosError(err int) error {
if err == 0 {
return nil
}
return RadosError(err)
}
// Version returns the major, minor, and patch components of the version of
// the RADOS library linked against.
func Version() (int, int, int) {
var c_major, c_minor, c_patch C.int
C.rados_version(&c_major, &c_minor, &c_patch)
return int(c_major), int(c_minor), int(c_patch)
}
func makeConn() *Conn {
return &Conn{connected: false}
}
func newConn(user *C.char) (*Conn, error) {
conn := makeConn()
ret := C.rados_create(&conn.cluster, user)
if ret != 0 {
return nil, RadosError(int(ret))
}
runtime.SetFinalizer(conn, freeConn)
return conn, nil
}
// NewConn creates a new connection object. It returns the connection and an
// error, if any.
func NewConn() (*Conn, error) {
return newConn(nil)
}
// NewConnWithUser creates a new connection object with a custom username.
// It returns the connection and an error, if any.
func NewConnWithUser(user string) (*Conn, error) {
c_user := C.CString(user)
defer C.free(unsafe.Pointer(c_user))
return newConn(c_user)
}
// NewConnWithClusterAndUser creates a new connection object for a specific cluster and username.
// It returns the connection and an error, if any.
func NewConnWithClusterAndUser(clusterName string, userName string) (*Conn, error) {
c_cluster_name := C.CString(clusterName)
defer C.free(unsafe.Pointer(c_cluster_name))
c_name := C.CString(userName)
defer C.free(unsafe.Pointer(c_name))
conn := makeConn()
ret := C.rados_create2(&conn.cluster, c_cluster_name, c_name, 0)
if ret != 0 {
return nil, RadosError(int(ret))
}
runtime.SetFinalizer(conn, freeConn)
return conn, nil
}
// freeConn releases resources that are allocated while configuring the
// connection to the cluster. rados_shutdown() should only be needed after a
// successful call to rados_connect(), however if the connection has been
// configured with non-default parameters, some of the parameters may be
// allocated before connecting. rados_shutdown() will free the allocated
// resources, even if there has not been a connection yet.
//
// This function is setup as a destructor/finalizer when rados_create() is
// called.
func freeConn(conn *Conn) {
if conn.cluster != nil {
C.rados_shutdown(conn.cluster)
// prevent calling rados_shutdown() more than once
conn.cluster = nil
}
}