/
ioctx.go
725 lines (633 loc) · 19.5 KB
/
ioctx.go
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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"
"github.com/ceph/go-ceph/internal/retry"
)
// 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
defaultListObjectsResultSize = 1000
// listEndSentinel is the value returned by rados_list_object_list_is_end
// when a cursor has reached the end of a pool
listEndSentinel = 1
)
//revive:disable:var-naming old-yet-exported public api
// 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
}
//revive:enable:var-naming
// 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
// Hold a reference back to the connection that the ioctx depends on so
// that Go's GC doesn't trigger the Conn's finalizer before this
// IOContext is destroyed.
conn *Conn
}
// validate returns an error if the ioctx is not ready to be used
// with ceph C calls.
func (ioctx *IOContext) validate() error {
if ioctx.ioctx == nil {
return ErrInvalidIOContext
}
return nil
}
// 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.
//
// Implements:
//
// void rados_ioctx_set_namespace(rados_ioctx_t io,
// const char *nspace);
func (ioctx *IOContext) SetNamespace(namespace string) {
var cns *C.char
if len(namespace) > 0 {
cns = C.CString(namespace)
defer C.free(unsafe.Pointer(cns))
}
C.rados_ioctx_set_namespace(ioctx.ioctx, cns)
}
// 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 {
op := CreateWriteOp()
defer op.Release()
op.Create(exclusive)
return op.operateCompat(ioctx, oid)
}
// 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 {
coid := C.CString(oid)
defer C.free(unsafe.Pointer(coid))
dataPointer := unsafe.Pointer(nil)
if len(data) > 0 {
dataPointer = unsafe.Pointer(&data[0])
}
ret := C.rados_write(ioctx.ioctx, coid,
(*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 {
coid := C.CString(oid)
defer C.free(unsafe.Pointer(coid))
ret := C.rados_write_full(ioctx.ioctx, coid,
(*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 {
coid := C.CString(oid)
defer C.free(unsafe.Pointer(coid))
ret := C.rados_append(ioctx.ioctx, coid,
(*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) {
coid := C.CString(oid)
defer C.free(unsafe.Pointer(coid))
var buf *C.char
if len(data) > 0 {
buf = (*C.char)(unsafe.Pointer(&data[0]))
}
ret := C.rados_read(
ioctx.ioctx,
coid,
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 {
coid := C.CString(oid)
defer C.free(unsafe.Pointer(coid))
return getError(C.rados_remove(ioctx.ioctx, coid))
}
// 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 {
coid := C.CString(oid)
defer C.free(unsafe.Pointer(coid))
return getError(C.rados_trunc(ioctx.ioctx, coid, (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) {
cStat := C.struct_rados_pool_stat_t{}
ret := C.rados_ioctx_pool_stat(ioctx.ioctx, &cStat)
if ret < 0 {
return PoolStat{}, getError(ret)
}
return PoolStat{
Num_bytes: uint64(cStat.num_bytes),
Num_kb: uint64(cStat.num_kb),
Num_objects: uint64(cStat.num_objects),
Num_object_clones: uint64(cStat.num_object_clones),
Num_object_copies: uint64(cStat.num_object_copies),
Num_objects_missing_on_primary: uint64(cStat.num_objects_missing_on_primary),
Num_objects_unfound: uint64(cStat.num_objects_unfound),
Num_objects_degraded: uint64(cStat.num_objects_degraded),
Num_rd: uint64(cStat.num_rd),
Num_rd_kb: uint64(cStat.num_rd_kb),
Num_wr: uint64(cStat.num_wr),
Num_wr_kb: uint64(cStat.num_wr_kb),
}, nil
}
// GetPoolID returns the pool ID associated with the I/O context.
//
// Implements:
//
// int64_t rados_ioctx_get_id(rados_ioctx_t io)
func (ioctx *IOContext) GetPoolID() int64 {
ret := C.rados_ioctx_get_id(ioctx.ioctx)
return int64(ret)
}
// GetPoolName returns the name of the pool associated with the I/O context.
func (ioctx *IOContext) GetPoolName() (name string, err error) {
var (
buf []byte
ret C.int
)
retry.WithSizes(128, 8192, func(size int) retry.Hint {
buf = make([]byte, size)
ret = C.rados_ioctx_get_pool_name(
ioctx.ioctx,
(*C.char)(unsafe.Pointer(&buf[0])),
C.unsigned(len(buf)))
err = getErrorIfNegative(ret)
return retry.DoubleSize.If(err == errRange)
})
if err != nil {
return "", err
}
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 {
pageResults := C.size_t(defaultListObjectsResultSize)
var filterLen C.size_t
results := make([]C.rados_object_list_item, pageResults)
next := C.rados_object_list_begin(ioctx.ioctx)
if next == nil {
return ErrNotFound
}
defer C.rados_object_list_cursor_free(ioctx.ioctx, next)
finish := C.rados_object_list_end(ioctx.ioctx)
if finish == nil {
return ErrNotFound
}
defer C.rados_object_list_cursor_free(ioctx.ioctx, finish)
for {
res := (*C.rados_object_list_item)(unsafe.Pointer(&results[0]))
ret := C.rados_object_list(ioctx.ioctx, next, finish, pageResults, nil, filterLen, res, &next)
if ret < 0 {
return getError(ret)
}
numEntries := int(ret)
for i := 0; i < numEntries; i++ {
item := results[i]
listFn(C.GoStringN(item.oid, (C.int)(item.oid_length)))
}
C.rados_object_list_free(C.size_t(ret), res)
if C.rados_object_list_is_end(ioctx.ioctx, next) == listEndSentinel {
return nil
}
}
}
// Stat returns the size of the object and its last modification time
func (ioctx *IOContext) Stat(object string) (stat ObjectStat, err error) {
var cPsize C.uint64_t
var cPmtime C.time_t
cObject := C.CString(object)
defer C.free(unsafe.Pointer(cObject))
ret := C.rados_stat(
ioctx.ioctx,
cObject,
&cPsize,
&cPmtime)
if ret < 0 {
return ObjectStat{}, getError(ret)
}
return ObjectStat{
Size: uint64(cPsize),
ModTime: time.Unix(int64(cPmtime), 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) {
cObject := C.CString(object)
cName := C.CString(name)
defer C.free(unsafe.Pointer(cObject))
defer C.free(unsafe.Pointer(cName))
ret := C.rados_getxattr(
ioctx.ioctx,
cObject,
cName,
(*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 {
cObject := C.CString(object)
cName := C.CString(name)
defer C.free(unsafe.Pointer(cObject))
defer C.free(unsafe.Pointer(cName))
ret := C.rados_setxattr(
ioctx.ioctx,
cObject,
cName,
(*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) {
coid := C.CString(oid)
defer C.free(unsafe.Pointer(coid))
var it C.rados_xattrs_iter_t
ret := C.rados_getxattrs(ioctx.ioctx, coid, &it)
if ret < 0 {
return nil, getError(ret)
}
defer func() { C.rados_getxattrs_end(it) }()
m := make(map[string][]byte)
for {
var cName, cVal *C.char
var cLen C.size_t
defer C.free(unsafe.Pointer(cName))
defer C.free(unsafe.Pointer(cVal))
ret := C.rados_getxattrs_next(it, &cName, &cVal, &cLen)
if ret < 0 {
return nil, getError(ret)
}
// rados api returns a null name,val & 0-length upon
// end of iteration
if cName == nil {
return m, nil // stop iteration
}
m[C.GoString(cName)] = C.GoBytes(unsafe.Pointer(cVal), (C.int)(cLen))
}
}
// RmXattr removes an xattr with key `name` from object `oid`
func (ioctx *IOContext) RmXattr(oid string, name string) error {
coid := C.CString(oid)
cName := C.CString(name)
defer C.free(unsafe.Pointer(coid))
defer C.free(unsafe.Pointer(cName))
ret := C.rados_rmxattr(
ioctx.ioctx,
coid,
cName)
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) {
coid := C.CString(oid)
cName := C.CString(name)
cCookie := C.CString(cookie)
cDesc := C.CString(desc)
var cDuration C.struct_timeval
if duration != 0 {
tv := syscall.NsecToTimeval(duration.Nanoseconds())
cDuration = C.struct_timeval{tv_sec: C.ceph_time_t(tv.Sec), tv_usec: C.ceph_suseconds_t(tv.Usec)}
}
var cFlags C.uint8_t
if flags != nil {
cFlags = C.uint8_t(*flags)
}
defer C.free(unsafe.Pointer(coid))
defer C.free(unsafe.Pointer(cName))
defer C.free(unsafe.Pointer(cCookie))
defer C.free(unsafe.Pointer(cDesc))
ret := C.rados_lock_exclusive(
ioctx.ioctx,
coid,
cName,
cCookie,
cDesc,
&cDuration,
cFlags)
// 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) {
coid := C.CString(oid)
cName := C.CString(name)
cCookie := C.CString(cookie)
cTag := C.CString(tag)
cDesc := C.CString(desc)
var cDuration C.struct_timeval
if duration != 0 {
tv := syscall.NsecToTimeval(duration.Nanoseconds())
cDuration = C.struct_timeval{tv_sec: C.ceph_time_t(tv.Sec), tv_usec: C.ceph_suseconds_t(tv.Usec)}
}
var cFlags C.uint8_t
if flags != nil {
cFlags = C.uint8_t(*flags)
}
defer C.free(unsafe.Pointer(coid))
defer C.free(unsafe.Pointer(cName))
defer C.free(unsafe.Pointer(cCookie))
defer C.free(unsafe.Pointer(cTag))
defer C.free(unsafe.Pointer(cDesc))
ret := C.rados_lock_shared(
ioctx.ioctx,
coid,
cName,
cCookie,
cTag,
cDesc,
&cDuration,
cFlags)
// 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) {
coid := C.CString(oid)
cName := C.CString(name)
cCookie := C.CString(cookie)
defer C.free(unsafe.Pointer(coid))
defer C.free(unsafe.Pointer(cName))
defer C.free(unsafe.Pointer(cCookie))
// 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,
coid,
cName,
cCookie)
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) {
coid := C.CString(oid)
cName := C.CString(name)
cTag := (*C.char)(C.malloc(C.size_t(1024)))
cClients := (*C.char)(C.malloc(C.size_t(1024)))
cCookies := (*C.char)(C.malloc(C.size_t(1024)))
cAddrs := (*C.char)(C.malloc(C.size_t(1024)))
var cExclusive C.int
cTagLen := C.size_t(1024)
cClientsLen := C.size_t(1024)
cCookiesLen := C.size_t(1024)
cAddrsLen := C.size_t(1024)
defer C.free(unsafe.Pointer(coid))
defer C.free(unsafe.Pointer(cName))
defer C.free(unsafe.Pointer(cTag))
defer C.free(unsafe.Pointer(cClients))
defer C.free(unsafe.Pointer(cCookies))
defer C.free(unsafe.Pointer(cAddrs))
ret := C.rados_list_lockers(
ioctx.ioctx,
coid,
cName,
&cExclusive,
cTag,
&cTagLen,
cClients,
&cClientsLen,
cCookies,
&cCookiesLen,
cAddrs,
&cAddrsLen)
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), cExclusive == 1, C.GoString(cTag), splitCString(cClients, cClientsLen), splitCString(cCookies, cCookiesLen), splitCString(cAddrs, cAddrsLen)}, 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) {
coid := C.CString(oid)
cName := C.CString(name)
cClient := C.CString(client)
cCookie := C.CString(cookie)
defer C.free(unsafe.Pointer(coid))
defer C.free(unsafe.Pointer(cName))
defer C.free(unsafe.Pointer(cClient))
defer C.free(unsafe.Pointer(cCookie))
// 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,
coid,
cName,
cClient,
cCookie)
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)
}
}
// GetLastVersion will return the version number of the last object read or
// written to.
//
// Implements:
//
// uint64_t rados_get_last_version(rados_ioctx_t io);
func (ioctx *IOContext) GetLastVersion() (uint64, error) {
if err := ioctx.validate(); err != nil {
return 0, err
}
v := C.rados_get_last_version(ioctx.ioctx)
return uint64(v), nil
}
// GetNamespace gets the namespace used for objects within this IO context.
//
// Implements:
//
// int rados_ioctx_get_namespace(rados_ioctx_t io, char *buf,
// unsigned maxlen);
func (ioctx *IOContext) GetNamespace() (string, error) {
if err := ioctx.validate(); err != nil {
return "", err
}
var (
err error
buf []byte
ret C.int
)
retry.WithSizes(128, 8192, func(size int) retry.Hint {
buf = make([]byte, size)
ret = C.rados_ioctx_get_namespace(
ioctx.ioctx,
(*C.char)(unsafe.Pointer(&buf[0])),
C.unsigned(len(buf)))
err = getErrorIfNegative(ret)
return retry.DoubleSize.If(err == errRange)
})
if err != nil {
return "", err
}
return string(buf[:ret]), nil
}