gerrit.o-ran-sc Code Review - ric-plt/xapp-frame-py.git/blob

1 # ==================================================================================

4 #

5 # Licensed under the Apache License, Version 2.0 (the "License");

6 # you may not use this file except in compliance with the License.

7 # You may obtain a copy of the License at

8 #

9 # http://www.apache.org/licenses/LICENSE-2.0

10 #

11 # Unless required by applicable law or agreed to in writing, software

12 # distributed under the License is distributed on an "AS IS" BASIS,

13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

14 # See the License for the specific language governing permissions and

15 # limitations under the License.

16 # ==================================================================================

17 import uuid

18 from ctypes import POINTER, Structure

19 from ctypes import c_int, c_char, c_char_p, c_void_p, memmove, cast, create_string_buffer

21 from ricxappframe.rmr.exceptions import BadBufferAllocation, MeidSizeOutOfRange, InitFailed

22 from ricxappframe.rmr.rmrclib.rmrclib import rmr_c_lib, get_constants, state_to_status

24 ##############

25 # PRIVATE API

26 ##############

29 def _get_rmr_constant(key: str, default=None):

30 """

31 Gets the constant with the named key from the RMR C library.

32 Returns None if the value is not a simple type. This happens

33 during sphinx autodoc document generation, which mocks the

34 rmrclib package to work without the RMR shared object file.

35 """

36 val = get_constants().get(key, default)

37 return val if isinstance(val, (type(None), str, int, float, bool)) else None

40 ##############

41 # PUBLIC API

42 ##############

44 # Publish constants from RMR C-language header files for use by importers of this library.

45 # TODO: Are there others that will be useful?

46 #: Typical size message to receive; size is not limited

47 RMR_MAX_RCV_BYTES = _get_rmr_constant('RMR_MAX_RCV_BYTES')

48 #: Multi-threaded initialization flag

49 RMRFL_MTCALL = _get_rmr_constant('RMRFL_MTCALL', 0x02) # initialization flags

50 #: Empty flag

51 RMRFL_NONE = _get_rmr_constant('RMRFL_NONE', 0x0)

52 #: State constant for OK

53 RMR_OK = _get_rmr_constant('RMR_OK', 0x00)

54 #: State constant for timeout

55 RMR_ERR_TIMEOUT = _get_rmr_constant('RMR_ERR_TIMEOUT')

56 #: State constant for retry

57 RMR_ERR_RETRY = _get_rmr_constant('RMR_ERR_RETRY')

60 class rmr_mbuf_t(Structure):

61 """

62 Mirrors public members of type rmr_mbuf_t from RMR header file src/common/include/rmr.h

64 | typedef struct {

65 | int state; // state of processing

66 | int mtype; // message type

67 | int len; // length of data in the payload (send or received)

68 | unsigned char* payload; // transported data

69 | unsigned char* xaction; // pointer to fixed length transaction id bytes

70 | int sub_id; // subscription id

71 | int tp_state; // transport state (a.k.a errno)

72 |

73 | these things are off limits to the user application

74 |

75 | void* tp_buf; // underlying transport allocated pointer (e.g. nng message)

76 | void* header; // internal message header (whole buffer: header+payload)

77 | unsigned char* id; // if we need an ID in the message separate from the xaction id

78 | int flags; // various MFL (private) flags as needed

79 | int alloc_len; // the length of the allocated space (hdr+payload)

80 | } rmr_mbuf_t;

82 RE PAYLOADs type below, see the documentation for c_char_p:

83 class ctypes.c_char_p

84 Represents the C char * datatype when it points to a zero-terminated string.

85 For a general character pointer that may also point to binary data, POINTER(c_char)

86 must be used. The constructor accepts an integer address, or a bytes object.

87 """

89 _fields_ = [

90 ("state", c_int),

91 ("mtype", c_int),

92 ("len", c_int),

93 ("payload", POINTER(c_char)), # according to the following the python bytes are already unsigned

94 # https://bytes.com/topic/python/answers/695078-ctypes-unsigned-char

95 ("xaction", POINTER(c_char)),

96 ("sub_id", c_int),

97 ("tp_state", c_int),

98 ]

100

101 # argtypes and restype are important: https://stackoverflow.com/questions/24377845/ctype-why-specify-argtypes

102 _rmr_init = rmr_c_lib.rmr_init

103 _rmr_init.argtypes = [c_char_p, c_int, c_int]

104 _rmr_init.restype = c_void_p

105

106

107 def rmr_init(uproto_port: c_char_p, max_msg_size: int, flags: int) -> c_void_p:

108 """

109 Prepares the environment for sending and receiving messages.

110 Refer to RMR C documentation for method::

111

112 extern void* rmr_init(char* uproto_port, int max_msg_size, int flags)

113

114 This function raises an exception if the returned context is None.

115

116 Parameters

117 ----------

118 uproto_port: c_char_p

119 Pointer to bytes built from the port number as a string; e.g., b'4550'

120 max_msg_size: integer

121 Maximum message size to receive

122 flags: integer

123 RMR option flags

124

125 Returns

126 -------

127 c_void_p:

128 Pointer to RMR context

129 """

130 mrc = _rmr_init(uproto_port, max_msg_size, flags)

131 if mrc is None:

132 raise InitFailed()

133 return mrc

134

135

136 _rmr_ready = rmr_c_lib.rmr_ready

137 _rmr_ready.argtypes = [c_void_p]

138 _rmr_ready.restype = c_int

139

140

141 def rmr_ready(vctx: c_void_p) -> int:

142 """

143 Checks if a routing table has been received and installed.

144 Refer to RMR C documentation for method::

145

146 extern int rmr_ready(void* vctx)

147

148 Parameters

149 ----------

150 vctx: ctypes c_void_p

151 Pointer to RMR context

152

153 Returns

154 -------

155 1 for yes, 0 for no

156 """

157 return _rmr_ready(vctx)

158

159

160 _rmr_close = rmr_c_lib.rmr_close

161 _rmr_close.argtypes = [c_void_p]

162

163

164 def rmr_close(vctx: c_void_p):

165 """

166 Closes the listen socket.

167 Refer to RMR C documentation for method::

168

169 extern void rmr_close(void* vctx)

170

171 Parameters

172 ----------

173 vctx: ctypes c_void_p

174 Pointer to RMR context

175

176 Returns

177 -------

178 None

179 """

180 _rmr_close(vctx)

181

182

183 _rmr_set_stimeout = rmr_c_lib.rmr_set_stimeout

184 _rmr_set_stimeout.argtypes = [c_void_p, c_int]

185 _rmr_set_stimeout.restype = c_int

186

187

188 def rmr_set_stimeout(vctx: c_void_p, rloops: int) -> int:

189 """

190 Sets the configuration for how RMR will retry message send operations.

191 Refer to RMR C documentation for method::

192

193 extern int rmr_set_stimeout(void* vctx, int rloops)

194

195 Parameters

196 ----------

197 vctx: ctypes c_void_p

198 Pointer to RMR context

199 rloops: int

200 Number of retry loops

201

202 Returns

203 -------

204 0 on success, -1 on failure

205 """

206 return _rmr_set_stimeout(vctx, rloops)

207

208

209 _rmr_alloc_msg = rmr_c_lib.rmr_alloc_msg

210 _rmr_alloc_msg.argtypes = [c_void_p, c_int]

211 _rmr_alloc_msg.restype = POINTER(rmr_mbuf_t)

212

213

214 def rmr_alloc_msg(vctx: c_void_p, size: int,

215 payload=None, gen_transaction_id=False, mtype=None,

216 meid=None, sub_id=None, fixed_transaction_id=None):

217 """

218 Allocates and returns a buffer to write and send through the RMR library.

219 Refer to RMR C documentation for method::

220

221 extern rmr_mbuf_t* rmr_alloc_msg(void* vctx, int size)

222

223 Optionally populates the message from the remaining arguments.

224

225 TODO: on next API break, clean up transaction_id ugliness. Kept for now to preserve API.

226

227 Parameters

228 ----------

229 vctx: ctypes c_void_p

230 Pointer to RMR context

231 size: int

232 How much space to allocate

233 payload: bytes

234 if not None, attempts to set the payload

235 gen_transaction_id: bool

236 if True, generates and sets a transaction ID.

237 Note, option fixed_transaction_id overrides this option

238 mtype: bytes

239 if not None, sets the sbuf's message type

240 meid: bytes

241 if not None, sets the sbuf's meid

242 sub_id: bytes

243 if not None, sets the sbuf's subscription id

244 fixed_transaction_id: bytes

245 if not None, used as the transaction ID.

246 Note, this overrides the option gen_transaction_id

247

248 Returns

249 -------

250 c_void_p:

251 Pointer to rmr_mbuf structure

252 """

253 sbuf = _rmr_alloc_msg(vctx, size)

254 try:

255 # make sure the alloc worked

256 sbuf.contents

257

258 # set specified fields

259 if payload:

260 set_payload_and_length(payload, sbuf)

261

262 if fixed_transaction_id:

263 set_transaction_id(sbuf, fixed_transaction_id)

264 elif gen_transaction_id:

265 generate_and_set_transaction_id(sbuf)

266

267 if mtype:

268 sbuf.contents.mtype = mtype

269

270 if meid:

271 rmr_set_meid(sbuf, meid)

272

273 if sub_id:

274 sbuf.contents.sub_id = sub_id

275

276 return sbuf

277

278 except ValueError:

279 raise BadBufferAllocation

280

281

282 _rmr_realloc_payload = rmr_c_lib.rmr_realloc_payload

283 _rmr_realloc_payload.argtypes = [POINTER(rmr_mbuf_t), c_int, c_int, c_int] # new_len, copy, clone

284 _rmr_realloc_payload.restype = POINTER(rmr_mbuf_t)

285

286

287 def rmr_realloc_payload(ptr_mbuf: c_void_p, new_len: int, copy=False, clone=False):

288 """

289 Allocates and returns a message buffer large enough for the new length.

290 Refer to RMR C documentation for method::

291

292 extern rmr_mbuf_t* rmr_realloc_payload(rmr_mbuf_t*, int, int, int)

293

294 Parameters

295 ----------

296 ptr_mbuf: c_void_p

297 Pointer to rmr_mbuf structure

298 new_len: int

299 Length

300 copy: bool

301 Whether to copy the original paylod

302 clone: bool

303 Whether to clone the original buffer

304

305 Returns

306 -------

307 c_void_p:

308 Pointer to rmr_mbuf structure

309 """

310 return _rmr_realloc_payload(ptr_mbuf, new_len, copy, clone)

311

312

313 _rmr_free_msg = rmr_c_lib.rmr_free_msg

314 _rmr_free_msg.argtypes = [POINTER(rmr_mbuf_t)]

315 _rmr_free_msg.restype = None

316

317

318 def rmr_free_msg(ptr_mbuf: c_void_p):

319 """

320 Releases the message buffer.

321 Refer to RMR C documentation for method::

322

323 extern void rmr_free_msg(rmr_mbuf_t* mbuf )

324

325 Parameters

326 ----------

327 ptr_mbuf: c_void_p

328 Pointer to rmr_mbuf structure

329

330 Returns

331 -------

332 None

333 """

334 if ptr_mbuf is not None:

335 _rmr_free_msg(ptr_mbuf)

336

337

338 _rmr_payload_size = rmr_c_lib.rmr_payload_size

339 _rmr_payload_size.argtypes = [POINTER(rmr_mbuf_t)]

340 _rmr_payload_size.restype = c_int

341

342

343 def rmr_payload_size(ptr_mbuf: c_void_p) -> int:

344 """

345 Gets the number of bytes available in the payload.

346 Refer to RMR C documentation for method::

347

348 extern int rmr_payload_size(rmr_mbuf_t* msg)

349

350 Parameters

351 ----------

352 ptr_mbuf: c_void_p

353 Pointer to rmr_mbuf structure

354

355 Returns

356 -------

357 int:

358 Number of bytes available

359 """

360 return _rmr_payload_size(ptr_mbuf)

361

362

363 """

364 The following functions all seem to have the same interface

365 """

366

367 _rmr_send_msg = rmr_c_lib.rmr_send_msg

368 _rmr_send_msg.argtypes = [c_void_p, POINTER(rmr_mbuf_t)]

369 _rmr_send_msg.restype = POINTER(rmr_mbuf_t)

370

371

372 def rmr_send_msg(vctx: c_void_p, ptr_mbuf: POINTER(rmr_mbuf_t)) -> POINTER(rmr_mbuf_t):

373 """

374 Sends the message according to the routing table and returns an empty buffer.

375 Refer to RMR C documentation for method::

376

377 extern rmr_mbuf_t* rmr_send_msg(void* vctx, rmr_mbuf_t* msg)

378

379 Parameters

380 ----------

381 vctx: ctypes c_void_p

382 Pointer to RMR context

383 ptr_mbuf: c_void_p

384 Pointer to rmr_mbuf structure

385

386 Returns

387 -------

388 c_void_p:

389 Pointer to rmr_mbuf structure

390 """

391 return _rmr_send_msg(vctx, ptr_mbuf)

392

393

394 # TODO: the old message (Send param) is actually optional, but I don't know how to specify that in Ctypes.

395 _rmr_rcv_msg = rmr_c_lib.rmr_rcv_msg

396 _rmr_rcv_msg.argtypes = [c_void_p, POINTER(rmr_mbuf_t)]

397 _rmr_rcv_msg.restype = POINTER(rmr_mbuf_t)

398

399

400 def rmr_rcv_msg(vctx: c_void_p, ptr_mbuf: POINTER(rmr_mbuf_t)) -> POINTER(rmr_mbuf_t):

401 """

402 Waits for a message to arrive, and returns it.

403 Refer to RMR C documentation for method::

404

405 extern rmr_mbuf_t* rmr_rcv_msg(void* vctx, rmr_mbuf_t* old_msg)

406

407 Parameters

408 ----------

409 vctx: ctypes c_void_p

410 Pointer to RMR context

411 ptr_mbuf: c_void_p

412 Pointer to rmr_mbuf structure

413

414 Returns

415 -------

416 c_void_p:

417 Pointer to rmr_mbuf structure

418 """

419 return _rmr_rcv_msg(vctx, ptr_mbuf)

420

421

422 _rmr_torcv_msg = rmr_c_lib.rmr_torcv_msg

423 _rmr_torcv_msg.argtypes = [c_void_p, POINTER(rmr_mbuf_t), c_int]

424 _rmr_torcv_msg.restype = POINTER(rmr_mbuf_t)

425

426

427 def rmr_torcv_msg(vctx: c_void_p, ptr_mbuf: POINTER(rmr_mbuf_t), ms_to: int) -> POINTER(rmr_mbuf_t):

428 """

429 Waits up to the timeout value for a message to arrive, and returns it.

430 Refer to RMR C documentation for method::

431

432 extern rmr_mbuf_t* rmr_torcv_msg(void* vctx, rmr_mbuf_t* old_msg, int ms_to)

433

434 Parameters

435 ----------

436 vctx: ctypes c_void_p

437 Pointer to RMR context

438 ptr_mbuf: c_void_p

439 Pointer to rmr_mbuf structure

440 ms_to: int

441 Time out value in milliseconds

442

443 Returns

444 -------

445 c_void_p:

446 Pointer to rmr_mbuf structure

447 """

448 return _rmr_torcv_msg(vctx, ptr_mbuf, ms_to)

449

450

451 _rmr_rts_msg = rmr_c_lib.rmr_rts_msg

452 _rmr_rts_msg.argtypes = [c_void_p, POINTER(rmr_mbuf_t)]

453 _rmr_rts_msg.restype = POINTER(rmr_mbuf_t)

454

455

456 def rmr_rts_msg(vctx: c_void_p, ptr_mbuf: POINTER(rmr_mbuf_t), payload=None, mtype=None) -> POINTER(rmr_mbuf_t):

457 """

458 Sends a message to the originating endpoint and returns an empty buffer.

459 Refer to RMR C documentation for method::

460

461 extern rmr_mbuf_t* rmr_rts_msg(void* vctx, rmr_mbuf_t* msg)

462

463 additional features beyond c-rmr:

464 if payload is not None, attempts to set the payload

465 if mtype is not None, sets the sbuf's message type

466

467 Parameters

468 ----------

469 vctx: ctypes c_void_p

470 Pointer to an RMR context

471 ptr_mbuf: ctypes c_void_p

472 Pointer to an RMR message buffer

473 payload: bytes

474 Payload

475 mtype: bytes

476 Message type

477

478 Returns

479 -------

480 c_void_p:

481 Pointer to rmr_mbuf structure

482 """

483

484 if payload:

485 set_payload_and_length(payload, ptr_mbuf)

486

487 if mtype:

488 ptr_mbuf.contents.mtype = mtype

489

490 return _rmr_rts_msg(vctx, ptr_mbuf)

491

492

493 _rmr_call = rmr_c_lib.rmr_call

494 _rmr_call.argtypes = [c_void_p, POINTER(rmr_mbuf_t)]

495 _rmr_call.restype = POINTER(rmr_mbuf_t)

496

497

498 def rmr_call(vctx: c_void_p, ptr_mbuf: POINTER(rmr_mbuf_t)) -> POINTER(rmr_mbuf_t):

499 """

500 Sends a message, waits for a response and returns it.

501 Refer to RMR C documentation for method::

502

503 extern rmr_mbuf_t* rmr_call(void* vctx, rmr_mbuf_t* msg)

504

505 Parameters

506 ----------

507 ptr_mbuf: ctypes c_void_p

508 Pointer to an RMR message buffer

509

510 Returns

511 -------

512 c_void_p:

513 Pointer to rmr_mbuf structure

514 """

515 return _rmr_call(vctx, ptr_mbuf)

516

517

518 _rmr_bytes2meid = rmr_c_lib.rmr_bytes2meid

519 _rmr_bytes2meid.argtypes = [POINTER(rmr_mbuf_t), c_char_p, c_int]

520 _rmr_bytes2meid.restype = c_int

521

522

523 def rmr_set_meid(ptr_mbuf: POINTER(rmr_mbuf_t), byte_str: bytes) -> int:

524 """

525 Sets the managed entity field in the message and returns the number of bytes copied.

526 Refer to RMR C documentation for method::

527

528 extern int rmr_bytes2meid(rmr_mbuf_t* mbuf, unsigned char const* src, int len);

529

530 Caution: the meid length supported in an RMR message is 32 bytes, but C applications

531 expect this to be a nil terminated string and thus only 31 bytes are actually available.

532

533 Raises: exceptions.MeidSizeOutOfRang

534

535 Parameters

536 ----------

537 ptr_mbuf: ctypes c_void_p

538 Pointer to an RMR message buffer

539 byte_tr: bytes

540 Managed entity ID value

541

542 Returns

543 -------

544 int:

545 number of bytes copied

546 """

547 max = _get_rmr_constant("RMR_MAX_MEID", 32)

548 if len(byte_str) >= max:

549 raise MeidSizeOutOfRange

550

551 return _rmr_bytes2meid(ptr_mbuf, byte_str, len(byte_str))

552

553

554 # CAUTION: Some of the C functions expect a mutable buffer to copy the bytes into;

555 # if there is a get_* function below, use it to set up and return the

556 # buffer properly.

557

558 # extern unsigned char* rmr_get_meid(rmr_mbuf_t* mbuf, unsigned char* dest);

559 # we don't provide direct access to this function (unless it is asked for) because it is not really useful to provide your own buffer.

560 # Rather, rmr_get_meid does this for you, and just returns the string.

561 _rmr_get_meid = rmr_c_lib.rmr_get_meid

562 _rmr_get_meid.argtypes = [POINTER(rmr_mbuf_t), c_char_p]

563 _rmr_get_meid.restype = c_char_p

564

565

566 def rmr_get_meid(ptr_mbuf: POINTER(rmr_mbuf_t)) -> bytes:

567 """

568 Gets the managed entity ID (meid) from the message header.

569 This is a python-friendly version of RMR C method::

570

571 extern unsigned char* rmr_get_meid(rmr_mbuf_t* mbuf, unsigned char* dest);

572

573 Parameters

574 ----------

575 ptr_mbuf: ctypes c_void_p

576 Pointer to an RMR message buffer

577

578 Returns

579 -------

580 bytes:

581 Managed entity ID

582 """

583 sz = _get_rmr_constant("RMR_MAX_MEID", 32) # size for buffer to fill

584 buf = create_string_buffer(sz)

585 _rmr_get_meid(ptr_mbuf, buf)

586 return buf.value

587

588

589 _rmr_get_src = rmr_c_lib.rmr_get_src

590 _rmr_get_src.argtypes = [POINTER(rmr_mbuf_t), c_char_p]

591 _rmr_get_src.restype = c_char_p

592

593

594 def rmr_get_src(ptr_mbuf: POINTER(rmr_mbuf_t), dest: c_char_p) -> c_char_p:

595 """

596 Copies the message-source information to the buffer.

597 Refer to RMR C documentation for method::

598

599 extern unsigned char* rmr_get_src(rmr_mbuf_t* mbuf, unsigned char* dest);

600

601 Parameters

602 ----------

603 ptr_mbuf: ctypes POINTER(rmr_mbuf_t)

604 Pointer to an RMR message buffer

605 dest: ctypes c_char_p

606 Pointer to a buffer to receive the message source

607

608 Returns

609 -------

610 string:

611 message-source information

612 """

613 return _rmr_get_src(ptr_mbuf, dest)

614

615

616 # Methods that exist ONLY in rmr-python, and are not wrapped methods

617 # In hindsight, I wish i put these in a separate module, but leaving this here to prevent api breakage.

618

619

620 def get_payload(ptr_mbuf: c_void_p) -> bytes:

621 """

622 Gets the binary payload from the rmr_buf_t*.

623

624 Parameters

625 ----------

626 ptr_mbuf: ctypes c_void_p

627 Pointer to an rmr message buffer

628

629 Returns

630 -------

631 bytes:

632 the message payload

633 """

634 # Logic came from the answer here: https://stackoverflow.com/questions/55103298/python-ctypes-read-pointerc-char-in-python

635 sz = ptr_mbuf.contents.len

636 CharArr = c_char * sz

637 return CharArr(*ptr_mbuf.contents.payload[:sz]).raw

638

639

640 def get_xaction(ptr_mbuf: c_void_p) -> bytes:

641 """

642 Gets the transaction ID from the rmr_buf_t*.

643

644 Parameters

645 ----------

646 ptr_mbuf: ctypes c_void_p

647 Pointer to an rmr message buffer

648

649 Returns

650 -------

651 bytes:

652 the transaction id

653 """

654 val = cast(ptr_mbuf.contents.xaction, c_char_p).value

655 sz = _get_rmr_constant("RMR_MAX_XID", 0)

656 return val[:sz]

657

658

659 def message_summary(ptr_mbuf: c_void_p) -> dict:

660 """

661 Returns a dict with the fields of an RMR message.

662

663 Parameters

664 ----------

665 ptr_mbuf: ctypes c_void_p

666 Pointer to an rmr message buffer

667

668 Returns

669 -------

670 dict:

671 dict message summary

672 """

673 return {

674 "payload": get_payload(ptr_mbuf) if ptr_mbuf.contents.state == RMR_OK else None,

675 "payload length": ptr_mbuf.contents.len,

676 "message type": ptr_mbuf.contents.mtype,

677 "subscription id": ptr_mbuf.contents.sub_id,

678 "transaction id": get_xaction(ptr_mbuf),

679 "message state": ptr_mbuf.contents.state,

680 "message status": state_to_status(ptr_mbuf.contents.state),

681 "payload max size": rmr_payload_size(ptr_mbuf),

682 "meid": rmr_get_meid(ptr_mbuf),

683 "message source": get_src(ptr_mbuf),

684 "errno": ptr_mbuf.contents.tp_state,

685 }

686

687

688 def set_payload_and_length(byte_str: bytes, ptr_mbuf: c_void_p):

689 """

690 Sets an rmr payload and content length.

691

692 Parameters

693 ----------

694 byte_str: bytes

695 the bytes to set the payload to

696 ptr_mbuf: ctypes c_void_p

697 Pointer to an rmr message buffer

698

699 Returns

700 -------

701 None

702 """

703 if rmr_payload_size(ptr_mbuf) < len(byte_str): # existing message payload too small

704 ptr_mbuf = rmr_realloc_payload(ptr_mbuf, len(byte_str), True)

705

706 memmove(ptr_mbuf.contents.payload, byte_str, len(byte_str))

707 ptr_mbuf.contents.len = len(byte_str)

708

709

710 def generate_and_set_transaction_id(ptr_mbuf: c_void_p):

711 """

712 Generates a UUID and sets the RMR transaction id to it

713

714 Parameters

715 ----------

716 ptr_mbuf: ctypes c_void_p

717 Pointer to an rmr message buffer

718 """

719 set_transaction_id(ptr_mbuf, uuid.uuid1().hex.encode("utf-8"))

720

721

722 def set_transaction_id(ptr_mbuf: c_void_p, tid_bytes: bytes):

723 """

724 Sets an RMR transaction id

725 TODO: on next API break, merge these two functions. Not done now to preserve API.

726

727 Parameters

728 ----------

729 ptr_mbuf: ctypes c_void_p

730 Pointer to an rmr message buffer

731 tid_bytes: bytes

732 bytes of the desired transaction id

733 """

734 sz = _get_rmr_constant("RMR_MAX_XID", 0)

735 memmove(ptr_mbuf.contents.xaction, tid_bytes, sz)

736

737

738 def get_src(ptr_mbuf: c_void_p) -> str:

739 """

740 Gets the message source (likely host:port)

741

742 Parameters

743 ----------

744 ptr_mbuf: ctypes c_void_p

745 Pointer to an rmr message buffer

746

747 Returns

748 -------

749 string:

750 message source

751 """

752 sz = _get_rmr_constant("RMR_MAX_SRC", 64) # size to fill

753 buf = create_string_buffer(sz)

754 rmr_get_src(ptr_mbuf, buf)

755 return buf.value.decode()