| 1 | /* |
| 2 | * msgpack.c |
| 3 | * |
| 4 | * Copyright (C) 2020 Francis Deslauriers <francis.deslauriers@efficios.com> |
| 5 | * |
| 6 | * This library is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU Lesser General Public |
| 8 | * License as published by the Free Software Foundation; only |
| 9 | * version 2.1 of the License. |
| 10 | * |
| 11 | * This library is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | * Lesser General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU Lesser General Public |
| 17 | * License along with this library; if not, write to the Free Software |
| 18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 19 | */ |
| 20 | |
| 21 | #define _GNU_SOURCE |
| 22 | #define _LGPL_SOURCE |
| 23 | |
| 24 | #define MSGPACK_FIXSTR_ID_MASK 0xA0 |
| 25 | #define MSGPACK_FIXMAP_ID_MASK 0x80 |
| 26 | #define MSGPACK_FIXARRAY_ID_MASK 0x90 |
| 27 | |
| 28 | #define MSGPACK_NIL_ID 0xC0 |
| 29 | #define MSGPACK_FALSE_ID 0xC2 |
| 30 | #define MSGPACK_TRUE_ID 0xC3 |
| 31 | #define MSGPACK_MAP16_ID 0xDE |
| 32 | #define MSGPACK_ARRAY16_ID 0xDC |
| 33 | |
| 34 | #define MSGPACK_UINT8_ID 0xCC |
| 35 | #define MSGPACK_UINT16_ID 0xCD |
| 36 | #define MSGPACK_UINT32_ID 0xCE |
| 37 | #define MSGPACK_UINT64_ID 0xCF |
| 38 | |
| 39 | #define MSGPACK_INT8_ID 0xD0 |
| 40 | #define MSGPACK_INT16_ID 0xD1 |
| 41 | #define MSGPACK_INT32_ID 0xD2 |
| 42 | #define MSGPACK_INT64_ID 0xD3 |
| 43 | |
| 44 | #define MSGPACK_FLOAT64_ID 0xCB |
| 45 | #define MSGPACK_STR16_ID 0xDA |
| 46 | |
| 47 | #define MSGPACK_FIXINT_MAX ((1 << 7) - 1) |
| 48 | #define MSGPACK_FIXINT_MIN -(1 << 5) |
| 49 | #define MSGPACK_FIXMAP_MAX_COUNT 15 |
| 50 | #define MSGPACK_FIXARRAY_MAX_COUNT 15 |
| 51 | #define MSGPACK_FIXSTR_MAX_LENGTH 31 |
| 52 | |
| 53 | #ifdef __KERNEL__ |
| 54 | #include <linux/bug.h> |
| 55 | #include <linux/string.h> |
| 56 | #include <linux/types.h> |
| 57 | #include <asm/byteorder.h> |
| 58 | |
| 59 | #include <lttng/msgpack.h> |
| 60 | #include <lttng/probe-user.h> |
| 61 | |
| 62 | #define INT8_MIN (-128) |
| 63 | #define INT16_MIN (-32767-1) |
| 64 | #define INT32_MIN (-2147483647-1) |
| 65 | #define INT8_MAX (127) |
| 66 | #define INT16_MAX (32767) |
| 67 | #define INT32_MAX (2147483647) |
| 68 | #define UINT8_MAX (255) |
| 69 | #define UINT16_MAX (65535) |
| 70 | #define UINT32_MAX (4294967295U) |
| 71 | |
| 72 | #define byteswap_host_to_be16(_tmp) cpu_to_be16(_tmp) |
| 73 | #define byteswap_host_to_be32(_tmp) cpu_to_be32(_tmp) |
| 74 | #define byteswap_host_to_be64(_tmp) cpu_to_be64(_tmp) |
| 75 | |
| 76 | #define lttng_msgpack_assert(cond) WARN_ON(!(cond)) |
| 77 | |
| 78 | #else /* __KERNEL__ */ |
| 79 | |
| 80 | #include <endian.h> |
| 81 | #include <stdio.h> |
| 82 | #include <string.h> |
| 83 | |
| 84 | #include "msgpack.h" |
| 85 | |
| 86 | #define byteswap_host_to_be16(_tmp) htobe16(_tmp) |
| 87 | #define byteswap_host_to_be32(_tmp) htobe32(_tmp) |
| 88 | #define byteswap_host_to_be64(_tmp) htobe64(_tmp) |
| 89 | |
| 90 | #define lttng_msgpack_assert(cond) ({ \ |
| 91 | if (!(cond)) \ |
| 92 | fprintf(stderr, "Assertion failed. %s:%d\n", __FILE__, __LINE__); \ |
| 93 | }) |
| 94 | #endif /* __KERNEL__ */ |
| 95 | |
| 96 | static inline int lttng_msgpack_append_buffer( |
| 97 | struct lttng_msgpack_writer *writer, |
| 98 | const uint8_t *buf, |
| 99 | size_t length) |
| 100 | { |
| 101 | int ret = 0; |
| 102 | |
| 103 | lttng_msgpack_assert(buf); |
| 104 | |
| 105 | /* Ensure we are not trying to write after the end of the buffer. */ |
| 106 | if (writer->write_pos + length > writer->end_write_pos) { |
| 107 | ret = -1; |
| 108 | goto end; |
| 109 | } |
| 110 | |
| 111 | memcpy(writer->write_pos, buf, length); |
| 112 | writer->write_pos += length; |
| 113 | end: |
| 114 | return ret; |
| 115 | } |
| 116 | |
| 117 | static inline int lttng_msgpack_append_user_buffer( |
| 118 | struct lttng_msgpack_writer *writer, |
| 119 | const uint8_t __user *ubuf, |
| 120 | size_t length) |
| 121 | { |
| 122 | int ret = 0; |
| 123 | |
| 124 | lttng_msgpack_assert(ubuf); |
| 125 | |
| 126 | /* Ensure we are not trying to write after the end of the buffer. */ |
| 127 | if (writer->write_pos + length > writer->end_write_pos) { |
| 128 | ret = -1; |
| 129 | goto end; |
| 130 | } |
| 131 | |
| 132 | if (lttng_copy_from_user_check_nofault(writer->write_pos, ubuf, length)) { |
| 133 | ret = -1; |
| 134 | goto end; |
| 135 | } |
| 136 | writer->write_pos += length; |
| 137 | end: |
| 138 | return ret; |
| 139 | } |
| 140 | |
| 141 | static inline int lttng_msgpack_append_u8( |
| 142 | struct lttng_msgpack_writer *writer, uint8_t value) |
| 143 | { |
| 144 | return lttng_msgpack_append_buffer(writer, &value, sizeof(value)); |
| 145 | } |
| 146 | |
| 147 | static inline int lttng_msgpack_append_u16( |
| 148 | struct lttng_msgpack_writer *writer, uint16_t value) |
| 149 | { |
| 150 | value = byteswap_host_to_be16(value); |
| 151 | |
| 152 | return lttng_msgpack_append_buffer(writer, (uint8_t *) &value, sizeof(value)); |
| 153 | } |
| 154 | |
| 155 | static inline int lttng_msgpack_append_u32( |
| 156 | struct lttng_msgpack_writer *writer, uint32_t value) |
| 157 | { |
| 158 | value = byteswap_host_to_be32(value); |
| 159 | |
| 160 | return lttng_msgpack_append_buffer(writer, (uint8_t *) &value, sizeof(value)); |
| 161 | } |
| 162 | |
| 163 | static inline int lttng_msgpack_append_u64( |
| 164 | struct lttng_msgpack_writer *writer, uint64_t value) |
| 165 | { |
| 166 | value = byteswap_host_to_be64(value); |
| 167 | |
| 168 | return lttng_msgpack_append_buffer(writer, (uint8_t *) &value, sizeof(value)); |
| 169 | } |
| 170 | |
| 171 | static inline int lttng_msgpack_append_i8( |
| 172 | struct lttng_msgpack_writer *writer, int8_t value) |
| 173 | { |
| 174 | return lttng_msgpack_append_u8(writer, (uint8_t) value); |
| 175 | } |
| 176 | |
| 177 | static inline int lttng_msgpack_append_i16( |
| 178 | struct lttng_msgpack_writer *writer, int16_t value) |
| 179 | { |
| 180 | return lttng_msgpack_append_u16(writer, (uint16_t) value); |
| 181 | } |
| 182 | |
| 183 | static inline int lttng_msgpack_append_i32( |
| 184 | struct lttng_msgpack_writer *writer, int32_t value) |
| 185 | { |
| 186 | return lttng_msgpack_append_u32(writer, (uint32_t) value); |
| 187 | } |
| 188 | |
| 189 | static inline int lttng_msgpack_append_i64( |
| 190 | struct lttng_msgpack_writer *writer, int64_t value) |
| 191 | { |
| 192 | return lttng_msgpack_append_u64(writer, (uint64_t) value); |
| 193 | } |
| 194 | |
| 195 | static inline int lttng_msgpack_encode_fixmap( |
| 196 | struct lttng_msgpack_writer *writer, uint8_t count) |
| 197 | { |
| 198 | int ret = 0; |
| 199 | |
| 200 | lttng_msgpack_assert(count <= MSGPACK_FIXMAP_MAX_COUNT); |
| 201 | |
| 202 | ret = lttng_msgpack_append_u8(writer, MSGPACK_FIXMAP_ID_MASK | count); |
| 203 | if (ret) |
| 204 | goto end; |
| 205 | |
| 206 | end: |
| 207 | return ret; |
| 208 | } |
| 209 | |
| 210 | static inline int lttng_msgpack_encode_map16( |
| 211 | struct lttng_msgpack_writer *writer, uint16_t count) |
| 212 | { |
| 213 | int ret; |
| 214 | |
| 215 | lttng_msgpack_assert(count > MSGPACK_FIXMAP_MAX_COUNT); |
| 216 | |
| 217 | ret = lttng_msgpack_append_u8(writer, MSGPACK_MAP16_ID); |
| 218 | if (ret) |
| 219 | goto end; |
| 220 | |
| 221 | ret = lttng_msgpack_append_u16(writer, count); |
| 222 | if (ret) |
| 223 | goto end; |
| 224 | |
| 225 | end: |
| 226 | return ret; |
| 227 | } |
| 228 | |
| 229 | static inline int lttng_msgpack_encode_fixarray( |
| 230 | struct lttng_msgpack_writer *writer, uint8_t count) |
| 231 | { |
| 232 | int ret = 0; |
| 233 | |
| 234 | lttng_msgpack_assert(count <= MSGPACK_FIXARRAY_MAX_COUNT); |
| 235 | |
| 236 | ret = lttng_msgpack_append_u8(writer, MSGPACK_FIXARRAY_ID_MASK | count); |
| 237 | if (ret) |
| 238 | goto end; |
| 239 | |
| 240 | end: |
| 241 | return ret; |
| 242 | } |
| 243 | |
| 244 | static inline int lttng_msgpack_encode_array16( |
| 245 | struct lttng_msgpack_writer *writer, uint16_t count) |
| 246 | { |
| 247 | int ret; |
| 248 | |
| 249 | lttng_msgpack_assert(count > MSGPACK_FIXARRAY_MAX_COUNT); |
| 250 | |
| 251 | ret = lttng_msgpack_append_u8(writer, MSGPACK_ARRAY16_ID); |
| 252 | if (ret) |
| 253 | goto end; |
| 254 | |
| 255 | ret = lttng_msgpack_append_u16(writer, count); |
| 256 | if (ret) |
| 257 | goto end; |
| 258 | |
| 259 | end: |
| 260 | return ret; |
| 261 | } |
| 262 | |
| 263 | static inline int lttng_msgpack_encode_fixstr( |
| 264 | struct lttng_msgpack_writer *writer, |
| 265 | const char *str, |
| 266 | uint8_t len) |
| 267 | { |
| 268 | int ret; |
| 269 | |
| 270 | lttng_msgpack_assert(len <= MSGPACK_FIXSTR_MAX_LENGTH); |
| 271 | |
| 272 | ret = lttng_msgpack_append_u8(writer, MSGPACK_FIXSTR_ID_MASK | len); |
| 273 | if (ret) |
| 274 | goto end; |
| 275 | |
| 276 | ret = lttng_msgpack_append_buffer(writer, (uint8_t *) str, len); |
| 277 | if (ret) |
| 278 | goto end; |
| 279 | |
| 280 | end: |
| 281 | return ret; |
| 282 | } |
| 283 | |
| 284 | static inline int lttng_msgpack_encode_str16( |
| 285 | struct lttng_msgpack_writer *writer, |
| 286 | const char *str, |
| 287 | uint16_t len) |
| 288 | { |
| 289 | int ret; |
| 290 | |
| 291 | lttng_msgpack_assert(len > MSGPACK_FIXSTR_MAX_LENGTH); |
| 292 | |
| 293 | ret = lttng_msgpack_append_u8(writer, MSGPACK_STR16_ID); |
| 294 | if (ret) |
| 295 | goto end; |
| 296 | |
| 297 | ret = lttng_msgpack_append_u16(writer, len); |
| 298 | if (ret) |
| 299 | goto end; |
| 300 | |
| 301 | ret = lttng_msgpack_append_buffer(writer, (uint8_t *) str, len); |
| 302 | if (ret) |
| 303 | goto end; |
| 304 | |
| 305 | end: |
| 306 | return ret; |
| 307 | } |
| 308 | |
| 309 | static inline int lttng_msgpack_encode_user_fixstr( |
| 310 | struct lttng_msgpack_writer *writer, |
| 311 | const char __user *ustr, |
| 312 | uint8_t len) |
| 313 | { |
| 314 | int ret; |
| 315 | |
| 316 | lttng_msgpack_assert(len <= MSGPACK_FIXSTR_MAX_LENGTH); |
| 317 | |
| 318 | ret = lttng_msgpack_append_u8(writer, MSGPACK_FIXSTR_ID_MASK | len); |
| 319 | if (ret) |
| 320 | goto end; |
| 321 | |
| 322 | ret = lttng_msgpack_append_user_buffer(writer, (uint8_t __user *) ustr, len); |
| 323 | if (ret) |
| 324 | goto end; |
| 325 | |
| 326 | end: |
| 327 | return ret; |
| 328 | } |
| 329 | |
| 330 | static inline int lttng_msgpack_encode_user_str16( |
| 331 | struct lttng_msgpack_writer *writer, |
| 332 | const char __user *ustr, |
| 333 | uint16_t len) |
| 334 | { |
| 335 | int ret; |
| 336 | |
| 337 | lttng_msgpack_assert(len > MSGPACK_FIXSTR_MAX_LENGTH); |
| 338 | |
| 339 | ret = lttng_msgpack_append_u8(writer, MSGPACK_STR16_ID); |
| 340 | if (ret) |
| 341 | goto end; |
| 342 | |
| 343 | ret = lttng_msgpack_append_u16(writer, len); |
| 344 | if (ret) |
| 345 | goto end; |
| 346 | |
| 347 | ret = lttng_msgpack_append_user_buffer(writer, (uint8_t __user *) ustr, len); |
| 348 | if (ret) |
| 349 | goto end; |
| 350 | |
| 351 | end: |
| 352 | return ret; |
| 353 | } |
| 354 | |
| 355 | |
| 356 | int lttng_msgpack_begin_map(struct lttng_msgpack_writer *writer, size_t count) |
| 357 | { |
| 358 | int ret; |
| 359 | |
| 360 | if (count >= (1 << 16)) { |
| 361 | ret = -1; |
| 362 | goto end; |
| 363 | } |
| 364 | |
| 365 | if (count <= MSGPACK_FIXMAP_MAX_COUNT) |
| 366 | ret = lttng_msgpack_encode_fixmap(writer, count); |
| 367 | else |
| 368 | ret = lttng_msgpack_encode_map16(writer, count); |
| 369 | |
| 370 | writer->map_nesting++; |
| 371 | end: |
| 372 | return ret; |
| 373 | } |
| 374 | |
| 375 | int lttng_msgpack_end_map(struct lttng_msgpack_writer *writer) |
| 376 | { |
| 377 | lttng_msgpack_assert(writer->map_nesting > 0); |
| 378 | writer->map_nesting--; |
| 379 | return 0; |
| 380 | } |
| 381 | |
| 382 | int lttng_msgpack_begin_array( |
| 383 | struct lttng_msgpack_writer *writer, size_t count) |
| 384 | { |
| 385 | int ret; |
| 386 | |
| 387 | if (count >= (1 << 16)) { |
| 388 | ret = -1; |
| 389 | goto end; |
| 390 | } |
| 391 | |
| 392 | if (count <= MSGPACK_FIXARRAY_MAX_COUNT) |
| 393 | ret = lttng_msgpack_encode_fixarray(writer, count); |
| 394 | else |
| 395 | ret = lttng_msgpack_encode_array16(writer, count); |
| 396 | |
| 397 | writer->array_nesting++; |
| 398 | end: |
| 399 | return ret; |
| 400 | } |
| 401 | |
| 402 | int lttng_msgpack_end_array(struct lttng_msgpack_writer *writer) |
| 403 | { |
| 404 | lttng_msgpack_assert(writer->array_nesting > 0); |
| 405 | writer->array_nesting--; |
| 406 | return 0; |
| 407 | } |
| 408 | |
| 409 | int lttng_msgpack_write_str(struct lttng_msgpack_writer *writer, |
| 410 | const char *str) |
| 411 | { |
| 412 | int ret; |
| 413 | size_t length = strlen(str); |
| 414 | |
| 415 | if (length >= (1 << 16)) { |
| 416 | ret = -1; |
| 417 | goto end; |
| 418 | } |
| 419 | |
| 420 | if (length <= MSGPACK_FIXSTR_MAX_LENGTH) |
| 421 | ret = lttng_msgpack_encode_fixstr(writer, str, length); |
| 422 | else |
| 423 | ret = lttng_msgpack_encode_str16(writer, str, length); |
| 424 | |
| 425 | end: |
| 426 | return ret; |
| 427 | } |
| 428 | |
| 429 | /* |
| 430 | * Provide the same behavior on lttng_strlen_user_inatomic page fault as the |
| 431 | * lttng ring buffer: truncate the last string character. |
| 432 | */ |
| 433 | int lttng_msgpack_write_user_str(struct lttng_msgpack_writer *writer, |
| 434 | const char __user *ustr) |
| 435 | { |
| 436 | int ret; |
| 437 | size_t length = max_t(size_t, lttng_strlen_user_inatomic(ustr), 1); |
| 438 | |
| 439 | if (length >= (1 << 16)) { |
| 440 | ret = -1; |
| 441 | goto end; |
| 442 | } |
| 443 | |
| 444 | if (length <= MSGPACK_FIXSTR_MAX_LENGTH) |
| 445 | ret = lttng_msgpack_encode_user_fixstr(writer, ustr, length); |
| 446 | else |
| 447 | ret = lttng_msgpack_encode_user_str16(writer, ustr, length); |
| 448 | |
| 449 | end: |
| 450 | return ret; |
| 451 | } |
| 452 | |
| 453 | int lttng_msgpack_write_nil(struct lttng_msgpack_writer *writer) |
| 454 | { |
| 455 | return lttng_msgpack_append_u8(writer, MSGPACK_NIL_ID); |
| 456 | } |
| 457 | |
| 458 | int lttng_msgpack_write_true(struct lttng_msgpack_writer *writer) |
| 459 | { |
| 460 | return lttng_msgpack_append_u8(writer, MSGPACK_TRUE_ID); |
| 461 | } |
| 462 | |
| 463 | int lttng_msgpack_write_false(struct lttng_msgpack_writer *writer) |
| 464 | { |
| 465 | return lttng_msgpack_append_u8(writer, MSGPACK_FALSE_ID); |
| 466 | } |
| 467 | |
| 468 | int lttng_msgpack_write_unsigned_integer( |
| 469 | struct lttng_msgpack_writer *writer, uint64_t value) |
| 470 | { |
| 471 | int ret = 0; |
| 472 | |
| 473 | if (value <= MSGPACK_FIXINT_MAX) { |
| 474 | ret = lttng_msgpack_append_u8(writer, (uint8_t) value); |
| 475 | if (ret) |
| 476 | goto end; |
| 477 | } else if (value <= UINT8_MAX) { |
| 478 | ret = lttng_msgpack_append_u8(writer, MSGPACK_UINT8_ID); |
| 479 | if (ret) |
| 480 | goto end; |
| 481 | |
| 482 | ret = lttng_msgpack_append_u8(writer, (uint8_t) value); |
| 483 | if (ret) |
| 484 | goto end; |
| 485 | } else if (value <= UINT16_MAX) { |
| 486 | ret = lttng_msgpack_append_u8(writer, MSGPACK_UINT16_ID); |
| 487 | if (ret) |
| 488 | goto end; |
| 489 | |
| 490 | ret = lttng_msgpack_append_u16(writer, (uint16_t) value); |
| 491 | if (ret) |
| 492 | goto end; |
| 493 | } else if (value <= UINT32_MAX) { |
| 494 | ret = lttng_msgpack_append_u8(writer, MSGPACK_UINT32_ID); |
| 495 | if (ret) |
| 496 | goto end; |
| 497 | |
| 498 | ret = lttng_msgpack_append_u32(writer, (uint32_t) value); |
| 499 | if (ret) |
| 500 | goto end; |
| 501 | } else { |
| 502 | ret = lttng_msgpack_append_u8(writer, MSGPACK_UINT64_ID); |
| 503 | if (ret) |
| 504 | goto end; |
| 505 | |
| 506 | ret = lttng_msgpack_append_u64(writer, value); |
| 507 | if (ret) |
| 508 | goto end; |
| 509 | } |
| 510 | |
| 511 | end: |
| 512 | return ret; |
| 513 | } |
| 514 | |
| 515 | int lttng_msgpack_write_signed_integer(struct lttng_msgpack_writer *writer, int64_t value) |
| 516 | { |
| 517 | int ret; |
| 518 | |
| 519 | if (value >= MSGPACK_FIXINT_MIN && value <= MSGPACK_FIXINT_MAX){ |
| 520 | ret = lttng_msgpack_append_i8(writer, (int8_t) value); |
| 521 | if (ret) |
| 522 | goto end; |
| 523 | } else if (value >= INT8_MIN && value <= INT8_MAX) { |
| 524 | ret = lttng_msgpack_append_u8(writer, MSGPACK_INT8_ID); |
| 525 | if (ret) |
| 526 | goto end; |
| 527 | |
| 528 | ret = lttng_msgpack_append_i8(writer, (int8_t) value); |
| 529 | if (ret) |
| 530 | goto end; |
| 531 | } else if (value >= INT16_MIN && value <= INT16_MAX) { |
| 532 | ret = lttng_msgpack_append_u8(writer, MSGPACK_INT16_ID); |
| 533 | if (ret) |
| 534 | goto end; |
| 535 | |
| 536 | ret = lttng_msgpack_append_i16(writer, (int16_t) value); |
| 537 | if (ret) |
| 538 | goto end; |
| 539 | } else if (value >= INT32_MIN && value <= INT32_MAX) { |
| 540 | ret = lttng_msgpack_append_u8(writer, MSGPACK_INT32_ID); |
| 541 | if (ret) |
| 542 | goto end; |
| 543 | |
| 544 | ret = lttng_msgpack_append_i32(writer, (int32_t) value); |
| 545 | if (ret) |
| 546 | goto end; |
| 547 | } else { |
| 548 | ret = lttng_msgpack_append_u8(writer, MSGPACK_INT64_ID); |
| 549 | if (ret) |
| 550 | goto end; |
| 551 | |
| 552 | ret = lttng_msgpack_append_i64(writer, value); |
| 553 | if (ret) |
| 554 | goto end; |
| 555 | } |
| 556 | |
| 557 | end: |
| 558 | return ret; |
| 559 | } |
| 560 | |
| 561 | int lttng_msgpack_save_writer_pos(struct lttng_msgpack_writer *writer, uint8_t **pos) |
| 562 | { |
| 563 | *pos = writer->write_pos; |
| 564 | return 0; |
| 565 | } |
| 566 | |
| 567 | int lttng_msgpack_restore_writer_pos(struct lttng_msgpack_writer *writer, uint8_t *pos) |
| 568 | { |
| 569 | writer->write_pos = pos; |
| 570 | return 0; |
| 571 | } |
| 572 | |
| 573 | void lttng_msgpack_writer_init(struct lttng_msgpack_writer *writer, |
| 574 | uint8_t *buffer, size_t size) |
| 575 | { |
| 576 | lttng_msgpack_assert(buffer); |
| 577 | lttng_msgpack_assert(size >= 0); |
| 578 | |
| 579 | writer->buffer = buffer; |
| 580 | writer->write_pos = buffer; |
| 581 | writer->end_write_pos = buffer + size; |
| 582 | |
| 583 | writer->array_nesting = 0; |
| 584 | writer->map_nesting = 0; |
| 585 | } |
| 586 | |
| 587 | void lttng_msgpack_writer_fini(struct lttng_msgpack_writer *writer) |
| 588 | { |
| 589 | memset(writer, 0, sizeof(*writer)); |
| 590 | } |