go-ceph/rados/ioctx.go

624 lines
17 KiB
Go

package rados
// #cgo LDFLAGS: -lrados
// #include <errno.h>
// #include <stdlib.h>
// #include <rados/librados.h>
//
// char* nextChunk(char **idx) {
// char *copy;
// copy = strdup(*idx);
// *idx += strlen(*idx) + 1;
// return copy;
// }
//
// #if __APPLE__
// #define ceph_time_t __darwin_time_t
// #define ceph_suseconds_t __darwin_suseconds_t
// #elif __GLIBC__
// #define ceph_time_t __time_t
// #define ceph_suseconds_t __suseconds_t
// #else
// #define ceph_time_t time_t
// #define ceph_suseconds_t suseconds_t
// #endif
import "C"
import (
"syscall"
"time"
"unsafe"
)
// CreateOption is passed to IOContext.Create() and should be one of
// CreateExclusive or CreateIdempotent.
type CreateOption int
const (
// CreateExclusive if used with IOContext.Create() and the object
// already exists, the function will return an error.
CreateExclusive = C.LIBRADOS_CREATE_EXCLUSIVE
// CreateIdempotent if used with IOContext.Create() and the object
// already exists, the function will not return an error.
CreateIdempotent = C.LIBRADOS_CREATE_IDEMPOTENT
)
// PoolStat represents Ceph pool statistics.
type PoolStat struct {
// space used in bytes
Num_bytes uint64
// space used in KB
Num_kb uint64
// number of objects in the pool
Num_objects uint64
// number of clones of objects
Num_object_clones uint64
// num_objects * num_replicas
Num_object_copies uint64
Num_objects_missing_on_primary uint64
// number of objects found on no OSDs
Num_objects_unfound uint64
// number of objects replicated fewer times than they should be
// (but found on at least one OSD)
Num_objects_degraded uint64
Num_rd uint64
Num_rd_kb uint64
Num_wr uint64
Num_wr_kb uint64
}
// ObjectStat represents an object stat information
type ObjectStat struct {
// current length in bytes
Size uint64
// last modification time
ModTime time.Time
}
// LockInfo represents information on a current Ceph lock
type LockInfo struct {
NumLockers int
Exclusive bool
Tag string
Clients []string
Cookies []string
Addrs []string
}
// IOContext represents a context for performing I/O within a pool.
type IOContext struct {
ioctx C.rados_ioctx_t
}
// Pointer returns a pointer reference to an internal structure.
// This function should NOT be used outside of go-ceph itself.
func (ioctx *IOContext) Pointer() unsafe.Pointer {
return unsafe.Pointer(ioctx.ioctx)
}
// SetNamespace sets the namespace for objects within this IO context (pool).
// Setting namespace to a empty or zero length string sets the pool to the default namespace.
func (ioctx *IOContext) SetNamespace(namespace string) {
var c_ns *C.char
if len(namespace) > 0 {
c_ns = C.CString(namespace)
defer C.free(unsafe.Pointer(c_ns))
}
C.rados_ioctx_set_namespace(ioctx.ioctx, c_ns)
}
// Create a new object with key oid.
//
// Implements:
// void rados_write_op_create(rados_write_op_t write_op, int exclusive,
// const char* category)
func (ioctx *IOContext) Create(oid string, exclusive CreateOption) error {
c_oid := C.CString(oid)
defer C.free(unsafe.Pointer(c_oid))
op := C.rados_create_write_op()
C.rados_write_op_create(op, C.int(exclusive), nil)
ret := C.rados_write_op_operate(op, ioctx.ioctx, c_oid, nil, 0)
C.rados_release_write_op(op)
return getError(ret)
}
// Write writes len(data) bytes to the object with key oid starting at byte
// offset offset. It returns an error, if any.
func (ioctx *IOContext) Write(oid string, data []byte, offset uint64) error {
c_oid := C.CString(oid)
defer C.free(unsafe.Pointer(c_oid))
dataPointer := unsafe.Pointer(nil)
if len(data) > 0 {
dataPointer = unsafe.Pointer(&data[0])
}
ret := C.rados_write(ioctx.ioctx, c_oid,
(*C.char)(dataPointer),
(C.size_t)(len(data)),
(C.uint64_t)(offset))
return getError(ret)
}
// WriteFull writes len(data) bytes to the object with key oid.
// The object is filled with the provided data. If the object exists,
// it is atomically truncated and then written. It returns an error, if any.
func (ioctx *IOContext) WriteFull(oid string, data []byte) error {
c_oid := C.CString(oid)
defer C.free(unsafe.Pointer(c_oid))
ret := C.rados_write_full(ioctx.ioctx, c_oid,
(*C.char)(unsafe.Pointer(&data[0])),
(C.size_t)(len(data)))
return getError(ret)
}
// Append appends len(data) bytes to the object with key oid.
// The object is appended with the provided data. If the object exists,
// it is atomically appended to. It returns an error, if any.
func (ioctx *IOContext) Append(oid string, data []byte) error {
c_oid := C.CString(oid)
defer C.free(unsafe.Pointer(c_oid))
ret := C.rados_append(ioctx.ioctx, c_oid,
(*C.char)(unsafe.Pointer(&data[0])),
(C.size_t)(len(data)))
return getError(ret)
}
// Read reads up to len(data) bytes from the object with key oid starting at byte
// offset offset. It returns the number of bytes read and an error, if any.
func (ioctx *IOContext) Read(oid string, data []byte, offset uint64) (int, error) {
c_oid := C.CString(oid)
defer C.free(unsafe.Pointer(c_oid))
var buf *C.char
if len(data) > 0 {
buf = (*C.char)(unsafe.Pointer(&data[0]))
}
ret := C.rados_read(
ioctx.ioctx,
c_oid,
buf,
(C.size_t)(len(data)),
(C.uint64_t)(offset))
if ret >= 0 {
return int(ret), nil
}
return 0, getError(ret)
}
// Delete deletes the object with key oid. It returns an error, if any.
func (ioctx *IOContext) Delete(oid string) error {
c_oid := C.CString(oid)
defer C.free(unsafe.Pointer(c_oid))
return getError(C.rados_remove(ioctx.ioctx, c_oid))
}
// Truncate resizes the object with key oid to size size. If the operation
// enlarges the object, the new area is logically filled with zeroes. If the
// operation shrinks the object, the excess data is removed. It returns an
// error, if any.
func (ioctx *IOContext) Truncate(oid string, size uint64) error {
c_oid := C.CString(oid)
defer C.free(unsafe.Pointer(c_oid))
return getError(C.rados_trunc(ioctx.ioctx, c_oid, (C.uint64_t)(size)))
}
// Destroy informs librados that the I/O context is no longer in use.
// Resources associated with the context may not be freed immediately, and the
// context should not be used again after calling this method.
func (ioctx *IOContext) Destroy() {
C.rados_ioctx_destroy(ioctx.ioctx)
}
// GetPoolStats returns a set of statistics about the pool associated with this I/O
// context.
//
// Implements:
// int rados_ioctx_pool_stat(rados_ioctx_t io,
// struct rados_pool_stat_t *stats);
func (ioctx *IOContext) GetPoolStats() (stat PoolStat, err error) {
c_stat := C.struct_rados_pool_stat_t{}
ret := C.rados_ioctx_pool_stat(ioctx.ioctx, &c_stat)
if ret < 0 {
return PoolStat{}, getError(ret)
}
return PoolStat{
Num_bytes: uint64(c_stat.num_bytes),
Num_kb: uint64(c_stat.num_kb),
Num_objects: uint64(c_stat.num_objects),
Num_object_clones: uint64(c_stat.num_object_clones),
Num_object_copies: uint64(c_stat.num_object_copies),
Num_objects_missing_on_primary: uint64(c_stat.num_objects_missing_on_primary),
Num_objects_unfound: uint64(c_stat.num_objects_unfound),
Num_objects_degraded: uint64(c_stat.num_objects_degraded),
Num_rd: uint64(c_stat.num_rd),
Num_rd_kb: uint64(c_stat.num_rd_kb),
Num_wr: uint64(c_stat.num_wr),
Num_wr_kb: uint64(c_stat.num_wr_kb),
}, nil
}
// GetPoolName returns the name of the pool associated with the I/O context.
func (ioctx *IOContext) GetPoolName() (name string, err error) {
buf := make([]byte, 128)
for {
ret := C.rados_ioctx_get_pool_name(ioctx.ioctx,
(*C.char)(unsafe.Pointer(&buf[0])), C.unsigned(len(buf)))
if ret == -C.ERANGE {
buf = make([]byte, len(buf)*2)
continue
} else if ret < 0 {
return "", getError(ret)
}
name = C.GoStringN((*C.char)(unsafe.Pointer(&buf[0])), ret)
return name, nil
}
}
// ObjectListFunc is the type of the function called for each object visited
// by ListObjects.
type ObjectListFunc func(oid string)
// ListObjects lists all of the objects in the pool associated with the I/O
// context, and called the provided listFn function for each object, passing
// to the function the name of the object. Call SetNamespace with
// RadosAllNamespaces before calling this function to return objects from all
// namespaces
func (ioctx *IOContext) ListObjects(listFn ObjectListFunc) error {
var ctx C.rados_list_ctx_t
ret := C.rados_nobjects_list_open(ioctx.ioctx, &ctx)
if ret < 0 {
return getError(ret)
}
defer func() { C.rados_nobjects_list_close(ctx) }()
for {
var c_entry *C.char
ret := C.rados_nobjects_list_next(ctx, &c_entry, nil, nil)
if ret == -C.ENOENT {
return nil
} else if ret < 0 {
return getError(ret)
}
listFn(C.GoString(c_entry))
}
}
// Stat returns the size of the object and its last modification time
func (ioctx *IOContext) Stat(object string) (stat ObjectStat, err error) {
var c_psize C.uint64_t
var c_pmtime C.time_t
c_object := C.CString(object)
defer C.free(unsafe.Pointer(c_object))
ret := C.rados_stat(
ioctx.ioctx,
c_object,
&c_psize,
&c_pmtime)
if ret < 0 {
return ObjectStat{}, getError(ret)
}
return ObjectStat{
Size: uint64(c_psize),
ModTime: time.Unix(int64(c_pmtime), 0),
}, nil
}
// GetXattr gets an xattr with key `name`, it returns the length of
// the key read or an error if not successful
func (ioctx *IOContext) GetXattr(object string, name string, data []byte) (int, error) {
c_object := C.CString(object)
c_name := C.CString(name)
defer C.free(unsafe.Pointer(c_object))
defer C.free(unsafe.Pointer(c_name))
ret := C.rados_getxattr(
ioctx.ioctx,
c_object,
c_name,
(*C.char)(unsafe.Pointer(&data[0])),
(C.size_t)(len(data)))
if ret >= 0 {
return int(ret), nil
}
return 0, getError(ret)
}
// SetXattr sets an xattr for an object with key `name` with value as `data`
func (ioctx *IOContext) SetXattr(object string, name string, data []byte) error {
c_object := C.CString(object)
c_name := C.CString(name)
defer C.free(unsafe.Pointer(c_object))
defer C.free(unsafe.Pointer(c_name))
ret := C.rados_setxattr(
ioctx.ioctx,
c_object,
c_name,
(*C.char)(unsafe.Pointer(&data[0])),
(C.size_t)(len(data)))
return getError(ret)
}
// ListXattrs lists all the xattrs for an object. The xattrs are returned as a
// mapping of string keys and byte-slice values.
func (ioctx *IOContext) ListXattrs(oid string) (map[string][]byte, error) {
c_oid := C.CString(oid)
defer C.free(unsafe.Pointer(c_oid))
var it C.rados_xattrs_iter_t
ret := C.rados_getxattrs(ioctx.ioctx, c_oid, &it)
if ret < 0 {
return nil, getError(ret)
}
defer func() { C.rados_getxattrs_end(it) }()
m := make(map[string][]byte)
for {
var c_name, c_val *C.char
var c_len C.size_t
defer C.free(unsafe.Pointer(c_name))
defer C.free(unsafe.Pointer(c_val))
ret := C.rados_getxattrs_next(it, &c_name, &c_val, &c_len)
if ret < 0 {
return nil, getError(ret)
}
// rados api returns a null name,val & 0-length upon
// end of iteration
if c_name == nil {
return m, nil // stop iteration
}
m[C.GoString(c_name)] = C.GoBytes(unsafe.Pointer(c_val), (C.int)(c_len))
}
}
// RmXattr removes an xattr with key `name` from object `oid`
func (ioctx *IOContext) RmXattr(oid string, name string) error {
c_oid := C.CString(oid)
c_name := C.CString(name)
defer C.free(unsafe.Pointer(c_oid))
defer C.free(unsafe.Pointer(c_name))
ret := C.rados_rmxattr(
ioctx.ioctx,
c_oid,
c_name)
return getError(ret)
}
// LockExclusive takes an exclusive lock on an object.
func (ioctx *IOContext) LockExclusive(oid, name, cookie, desc string, duration time.Duration, flags *byte) (int, error) {
c_oid := C.CString(oid)
c_name := C.CString(name)
c_cookie := C.CString(cookie)
c_desc := C.CString(desc)
var c_duration C.struct_timeval
if duration != 0 {
tv := syscall.NsecToTimeval(duration.Nanoseconds())
c_duration = C.struct_timeval{tv_sec: C.ceph_time_t(tv.Sec), tv_usec: C.ceph_suseconds_t(tv.Usec)}
}
var c_flags C.uint8_t
if flags != nil {
c_flags = C.uint8_t(*flags)
}
defer C.free(unsafe.Pointer(c_oid))
defer C.free(unsafe.Pointer(c_name))
defer C.free(unsafe.Pointer(c_cookie))
defer C.free(unsafe.Pointer(c_desc))
ret := C.rados_lock_exclusive(
ioctx.ioctx,
c_oid,
c_name,
c_cookie,
c_desc,
&c_duration,
c_flags)
// 0 on success, negative error code on failure
// -EBUSY if the lock is already held by another (client, cookie) pair
// -EEXIST if the lock is already held by the same (client, cookie) pair
switch ret {
case 0:
return int(ret), nil
case -C.EBUSY:
return int(ret), nil
case -C.EEXIST:
return int(ret), nil
default:
return int(ret), getError(ret)
}
}
// LockShared takes a shared lock on an object.
func (ioctx *IOContext) LockShared(oid, name, cookie, tag, desc string, duration time.Duration, flags *byte) (int, error) {
c_oid := C.CString(oid)
c_name := C.CString(name)
c_cookie := C.CString(cookie)
c_tag := C.CString(tag)
c_desc := C.CString(desc)
var c_duration C.struct_timeval
if duration != 0 {
tv := syscall.NsecToTimeval(duration.Nanoseconds())
c_duration = C.struct_timeval{tv_sec: C.ceph_time_t(tv.Sec), tv_usec: C.ceph_suseconds_t(tv.Usec)}
}
var c_flags C.uint8_t
if flags != nil {
c_flags = C.uint8_t(*flags)
}
defer C.free(unsafe.Pointer(c_oid))
defer C.free(unsafe.Pointer(c_name))
defer C.free(unsafe.Pointer(c_cookie))
defer C.free(unsafe.Pointer(c_tag))
defer C.free(unsafe.Pointer(c_desc))
ret := C.rados_lock_shared(
ioctx.ioctx,
c_oid,
c_name,
c_cookie,
c_tag,
c_desc,
&c_duration,
c_flags)
// 0 on success, negative error code on failure
// -EBUSY if the lock is already held by another (client, cookie) pair
// -EEXIST if the lock is already held by the same (client, cookie) pair
switch ret {
case 0:
return int(ret), nil
case -C.EBUSY:
return int(ret), nil
case -C.EEXIST:
return int(ret), nil
default:
return int(ret), getError(ret)
}
}
// Unlock releases a shared or exclusive lock on an object.
func (ioctx *IOContext) Unlock(oid, name, cookie string) (int, error) {
c_oid := C.CString(oid)
c_name := C.CString(name)
c_cookie := C.CString(cookie)
defer C.free(unsafe.Pointer(c_oid))
defer C.free(unsafe.Pointer(c_name))
defer C.free(unsafe.Pointer(c_cookie))
// 0 on success, negative error code on failure
// -ENOENT if the lock is not held by the specified (client, cookie) pair
ret := C.rados_unlock(
ioctx.ioctx,
c_oid,
c_name,
c_cookie)
switch ret {
case 0:
return int(ret), nil
case -C.ENOENT:
return int(ret), nil
default:
return int(ret), getError(ret)
}
}
// ListLockers lists clients that have locked the named object lock and
// information about the lock.
// The number of bytes required in each buffer is put in the corresponding size
// out parameter. If any of the provided buffers are too short, -ERANGE is
// returned after these sizes are filled in.
func (ioctx *IOContext) ListLockers(oid, name string) (*LockInfo, error) {
c_oid := C.CString(oid)
c_name := C.CString(name)
c_tag := (*C.char)(C.malloc(C.size_t(1024)))
c_clients := (*C.char)(C.malloc(C.size_t(1024)))
c_cookies := (*C.char)(C.malloc(C.size_t(1024)))
c_addrs := (*C.char)(C.malloc(C.size_t(1024)))
var c_exclusive C.int
c_tag_len := C.size_t(1024)
c_clients_len := C.size_t(1024)
c_cookies_len := C.size_t(1024)
c_addrs_len := C.size_t(1024)
defer C.free(unsafe.Pointer(c_oid))
defer C.free(unsafe.Pointer(c_name))
defer C.free(unsafe.Pointer(c_tag))
defer C.free(unsafe.Pointer(c_clients))
defer C.free(unsafe.Pointer(c_cookies))
defer C.free(unsafe.Pointer(c_addrs))
ret := C.rados_list_lockers(
ioctx.ioctx,
c_oid,
c_name,
&c_exclusive,
c_tag,
&c_tag_len,
c_clients,
&c_clients_len,
c_cookies,
&c_cookies_len,
c_addrs,
&c_addrs_len)
splitCString := func(items *C.char, itemsLen C.size_t) []string {
currLen := 0
clients := []string{}
for currLen < int(itemsLen) {
client := C.GoString(C.nextChunk(&items))
clients = append(clients, client)
currLen += len(client) + 1
}
return clients
}
if ret < 0 {
return nil, RadosError(ret)
}
return &LockInfo{int(ret), c_exclusive == 1, C.GoString(c_tag), splitCString(c_clients, c_clients_len), splitCString(c_cookies, c_cookies_len), splitCString(c_addrs, c_addrs_len)}, nil
}
// BreakLock releases a shared or exclusive lock on an object, which was taken by the specified client.
func (ioctx *IOContext) BreakLock(oid, name, client, cookie string) (int, error) {
c_oid := C.CString(oid)
c_name := C.CString(name)
c_client := C.CString(client)
c_cookie := C.CString(cookie)
defer C.free(unsafe.Pointer(c_oid))
defer C.free(unsafe.Pointer(c_name))
defer C.free(unsafe.Pointer(c_client))
defer C.free(unsafe.Pointer(c_cookie))
// 0 on success, negative error code on failure
// -ENOENT if the lock is not held by the specified (client, cookie) pair
// -EINVAL if the client cannot be parsed
ret := C.rados_break_lock(
ioctx.ioctx,
c_oid,
c_name,
c_client,
c_cookie)
switch ret {
case 0:
return int(ret), nil
case -C.ENOENT:
return int(ret), nil
case -C.EINVAL: // -EINVAL
return int(ret), nil
default:
return int(ret), getError(ret)
}
}