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Commit | Line | Data |
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9a4ac51f EH |
1 | /* |
2 | * QEMU System Emulator | |
3 | * | |
4 | * Copyright (c) 2003-2008 Fabrice Bellard | |
5 | * | |
6 | * Permission is hereby granted, free of charge, to any person obtaining a copy | |
7 | * of this software and associated documentation files (the "Software"), to deal | |
8 | * in the Software without restriction, including without limitation the rights | |
9 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | |
10 | * copies of the Software, and to permit persons to whom the Software is | |
11 | * furnished to do so, subject to the following conditions: | |
12 | * | |
13 | * The above copyright notice and this permission notice shall be included in | |
14 | * all copies or substantial portions of the Software. | |
15 | * | |
16 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
17 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
18 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
19 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
20 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | |
21 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN | |
22 | * THE SOFTWARE. | |
23 | */ | |
1393a485 | 24 | #include "qemu/osdep.h" |
44f0eadc | 25 | #include <zlib.h> |
d49b6836 | 26 | #include "qemu/error-report.h" |
093c455a | 27 | #include "qemu/iov.h" |
6666c96a | 28 | #include "migration.h" |
08a0aee1 | 29 | #include "qemu-file.h" |
9013dca5 | 30 | #include "trace.h" |
3d661c8a | 31 | #include "qapi/error.h" |
093c455a | 32 | |
a24939f2 DB |
33 | #define IO_BUF_SIZE 32768 |
34 | #define MAX_IOV_SIZE MIN(IOV_MAX, 64) | |
35 | ||
36 | struct QEMUFile { | |
37 | const QEMUFileOps *ops; | |
38 | const QEMUFileHooks *hooks; | |
39 | void *opaque; | |
40 | ||
41 | int64_t bytes_xfer; | |
42 | int64_t xfer_limit; | |
43 | ||
44 | int64_t pos; /* start of buffer when writing, end of buffer | |
45 | when reading */ | |
46 | int buf_index; | |
47 | int buf_size; /* 0 when writing */ | |
48 | uint8_t buf[IO_BUF_SIZE]; | |
49 | ||
53f09a10 | 50 | DECLARE_BITMAP(may_free, MAX_IOV_SIZE); |
a24939f2 DB |
51 | struct iovec iov[MAX_IOV_SIZE]; |
52 | unsigned int iovcnt; | |
53 | ||
54 | int last_error; | |
3d661c8a | 55 | Error *last_error_obj; |
a24939f2 DB |
56 | }; |
57 | ||
e1a8c9b6 DDAG |
58 | /* |
59 | * Stop a file from being read/written - not all backing files can do this | |
60 | * typically only sockets can. | |
61 | */ | |
62 | int qemu_file_shutdown(QEMUFile *f) | |
63 | { | |
64 | if (!f->ops->shut_down) { | |
65 | return -ENOSYS; | |
66 | } | |
3d661c8a | 67 | return f->ops->shut_down(f->opaque, true, true, NULL); |
e1a8c9b6 DDAG |
68 | } |
69 | ||
adc468e9 DDAG |
70 | /* |
71 | * Result: QEMUFile* for a 'return path' for comms in the opposite direction | |
72 | * NULL if not available | |
73 | */ | |
74 | QEMUFile *qemu_file_get_return_path(QEMUFile *f) | |
75 | { | |
76 | if (!f->ops->get_return_path) { | |
77 | return NULL; | |
78 | } | |
79 | return f->ops->get_return_path(f->opaque); | |
80 | } | |
81 | ||
093c455a EH |
82 | bool qemu_file_mode_is_not_valid(const char *mode) |
83 | { | |
84 | if (mode == NULL || | |
85 | (mode[0] != 'r' && mode[0] != 'w') || | |
86 | mode[1] != 'b' || mode[2] != 0) { | |
87 | fprintf(stderr, "qemu_fopen: Argument validity check failed\n"); | |
88 | return true; | |
89 | } | |
90 | ||
91 | return false; | |
92 | } | |
93 | ||
093c455a EH |
94 | QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops) |
95 | { | |
96 | QEMUFile *f; | |
97 | ||
97f3ad35 | 98 | f = g_new0(QEMUFile, 1); |
093c455a EH |
99 | |
100 | f->opaque = opaque; | |
101 | f->ops = ops; | |
102 | return f; | |
103 | } | |
104 | ||
0436e09f DB |
105 | |
106 | void qemu_file_set_hooks(QEMUFile *f, const QEMUFileHooks *hooks) | |
107 | { | |
108 | f->hooks = hooks; | |
109 | } | |
110 | ||
093c455a | 111 | /* |
3d661c8a | 112 | * Get last error for stream f with optional Error* |
093c455a EH |
113 | * |
114 | * Return negative error value if there has been an error on previous | |
115 | * operations, return 0 if no error happened. | |
3d661c8a YK |
116 | * Optional, it returns Error* in errp, but it may be NULL even if return value |
117 | * is not 0. | |
093c455a EH |
118 | * |
119 | */ | |
3d661c8a | 120 | int qemu_file_get_error_obj(QEMUFile *f, Error **errp) |
093c455a | 121 | { |
3d661c8a YK |
122 | if (errp) { |
123 | *errp = f->last_error_obj ? error_copy(f->last_error_obj) : NULL; | |
124 | } | |
093c455a EH |
125 | return f->last_error; |
126 | } | |
127 | ||
3d661c8a YK |
128 | /* |
129 | * Set the last error for stream f with optional Error* | |
130 | */ | |
131 | void qemu_file_set_error_obj(QEMUFile *f, int ret, Error *err) | |
093c455a | 132 | { |
3d661c8a | 133 | if (f->last_error == 0 && ret) { |
093c455a | 134 | f->last_error = ret; |
3d661c8a YK |
135 | error_propagate(&f->last_error_obj, err); |
136 | } else if (err) { | |
137 | error_report_err(err); | |
093c455a EH |
138 | } |
139 | } | |
140 | ||
3d661c8a YK |
141 | /* |
142 | * Get last error for stream f | |
143 | * | |
144 | * Return negative error value if there has been an error on previous | |
145 | * operations, return 0 if no error happened. | |
146 | * | |
147 | */ | |
148 | int qemu_file_get_error(QEMUFile *f) | |
149 | { | |
150 | return qemu_file_get_error_obj(f, NULL); | |
151 | } | |
152 | ||
153 | /* | |
154 | * Set the last error for stream f | |
155 | */ | |
156 | void qemu_file_set_error(QEMUFile *f, int ret) | |
157 | { | |
158 | qemu_file_set_error_obj(f, ret, NULL); | |
159 | } | |
160 | ||
e68dd365 | 161 | bool qemu_file_is_writable(QEMUFile *f) |
093c455a | 162 | { |
11808bb0 | 163 | return f->ops->writev_buffer; |
093c455a EH |
164 | } |
165 | ||
53f09a10 PB |
166 | static void qemu_iovec_release_ram(QEMUFile *f) |
167 | { | |
168 | struct iovec iov; | |
169 | unsigned long idx; | |
170 | ||
171 | /* Find and release all the contiguous memory ranges marked as may_free. */ | |
172 | idx = find_next_bit(f->may_free, f->iovcnt, 0); | |
173 | if (idx >= f->iovcnt) { | |
174 | return; | |
175 | } | |
176 | iov = f->iov[idx]; | |
177 | ||
178 | /* The madvise() in the loop is called for iov within a continuous range and | |
179 | * then reinitialize the iov. And in the end, madvise() is called for the | |
180 | * last iov. | |
181 | */ | |
182 | while ((idx = find_next_bit(f->may_free, f->iovcnt, idx + 1)) < f->iovcnt) { | |
183 | /* check for adjacent buffer and coalesce them */ | |
184 | if (iov.iov_base + iov.iov_len == f->iov[idx].iov_base) { | |
185 | iov.iov_len += f->iov[idx].iov_len; | |
186 | continue; | |
187 | } | |
188 | if (qemu_madvise(iov.iov_base, iov.iov_len, QEMU_MADV_DONTNEED) < 0) { | |
189 | error_report("migrate: madvise DONTNEED failed %p %zd: %s", | |
190 | iov.iov_base, iov.iov_len, strerror(errno)); | |
191 | } | |
192 | iov = f->iov[idx]; | |
193 | } | |
194 | if (qemu_madvise(iov.iov_base, iov.iov_len, QEMU_MADV_DONTNEED) < 0) { | |
195 | error_report("migrate: madvise DONTNEED failed %p %zd: %s", | |
196 | iov.iov_base, iov.iov_len, strerror(errno)); | |
197 | } | |
198 | memset(f->may_free, 0, sizeof(f->may_free)); | |
199 | } | |
200 | ||
093c455a EH |
201 | /** |
202 | * Flushes QEMUFile buffer | |
203 | * | |
3b348706 DDAG |
204 | * This will flush all pending data. If data was only partially flushed, it |
205 | * will set an error state. | |
093c455a EH |
206 | */ |
207 | void qemu_fflush(QEMUFile *f) | |
208 | { | |
209 | ssize_t ret = 0; | |
baf51e77 | 210 | ssize_t expect = 0; |
3d661c8a | 211 | Error *local_error = NULL; |
093c455a EH |
212 | |
213 | if (!qemu_file_is_writable(f)) { | |
214 | return; | |
215 | } | |
216 | ||
11808bb0 DB |
217 | if (f->iovcnt > 0) { |
218 | expect = iov_size(f->iov, f->iovcnt); | |
3d661c8a YK |
219 | ret = f->ops->writev_buffer(f->opaque, f->iov, f->iovcnt, f->pos, |
220 | &local_error); | |
53f09a10 PB |
221 | |
222 | qemu_iovec_release_ram(f); | |
093c455a | 223 | } |
baf51e77 | 224 | |
093c455a EH |
225 | if (ret >= 0) { |
226 | f->pos += ret; | |
227 | } | |
baf51e77 DB |
228 | /* We expect the QEMUFile write impl to send the full |
229 | * data set we requested, so sanity check that. | |
230 | */ | |
231 | if (ret != expect) { | |
3d661c8a | 232 | qemu_file_set_error_obj(f, ret < 0 ? ret : -EIO, local_error); |
baf51e77 | 233 | } |
093c455a EH |
234 | f->buf_index = 0; |
235 | f->iovcnt = 0; | |
093c455a EH |
236 | } |
237 | ||
238 | void ram_control_before_iterate(QEMUFile *f, uint64_t flags) | |
239 | { | |
240 | int ret = 0; | |
241 | ||
0436e09f DB |
242 | if (f->hooks && f->hooks->before_ram_iterate) { |
243 | ret = f->hooks->before_ram_iterate(f, f->opaque, flags, NULL); | |
093c455a EH |
244 | if (ret < 0) { |
245 | qemu_file_set_error(f, ret); | |
246 | } | |
247 | } | |
248 | } | |
249 | ||
250 | void ram_control_after_iterate(QEMUFile *f, uint64_t flags) | |
251 | { | |
252 | int ret = 0; | |
253 | ||
0436e09f DB |
254 | if (f->hooks && f->hooks->after_ram_iterate) { |
255 | ret = f->hooks->after_ram_iterate(f, f->opaque, flags, NULL); | |
093c455a EH |
256 | if (ret < 0) { |
257 | qemu_file_set_error(f, ret); | |
258 | } | |
259 | } | |
260 | } | |
261 | ||
632e3a5c | 262 | void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data) |
093c455a EH |
263 | { |
264 | int ret = -EINVAL; | |
265 | ||
0436e09f DB |
266 | if (f->hooks && f->hooks->hook_ram_load) { |
267 | ret = f->hooks->hook_ram_load(f, f->opaque, flags, data); | |
093c455a EH |
268 | if (ret < 0) { |
269 | qemu_file_set_error(f, ret); | |
270 | } | |
271 | } else { | |
632e3a5c DDAG |
272 | /* |
273 | * Hook is a hook specifically requested by the source sending a flag | |
274 | * that expects there to be a hook on the destination. | |
275 | */ | |
276 | if (flags == RAM_CONTROL_HOOK) { | |
277 | qemu_file_set_error(f, ret); | |
278 | } | |
093c455a EH |
279 | } |
280 | } | |
281 | ||
282 | size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset, | |
6e1dea46 JQ |
283 | ram_addr_t offset, size_t size, |
284 | uint64_t *bytes_sent) | |
093c455a | 285 | { |
0436e09f DB |
286 | if (f->hooks && f->hooks->save_page) { |
287 | int ret = f->hooks->save_page(f, f->opaque, block_offset, | |
288 | offset, size, bytes_sent); | |
ccb7e1b5 LC |
289 | if (ret != RAM_SAVE_CONTROL_NOT_SUPP) { |
290 | f->bytes_xfer += size; | |
291 | } | |
292 | ||
293 | if (ret != RAM_SAVE_CONTROL_DELAYED && | |
294 | ret != RAM_SAVE_CONTROL_NOT_SUPP) { | |
093c455a EH |
295 | if (bytes_sent && *bytes_sent > 0) { |
296 | qemu_update_position(f, *bytes_sent); | |
297 | } else if (ret < 0) { | |
298 | qemu_file_set_error(f, ret); | |
299 | } | |
300 | } | |
301 | ||
302 | return ret; | |
303 | } | |
304 | ||
305 | return RAM_SAVE_CONTROL_NOT_SUPP; | |
306 | } | |
307 | ||
548f52ea DDAG |
308 | /* |
309 | * Attempt to fill the buffer from the underlying file | |
310 | * Returns the number of bytes read, or negative value for an error. | |
311 | * | |
312 | * Note that it can return a partially full buffer even in a not error/not EOF | |
313 | * case if the underlying file descriptor gives a short read, and that can | |
314 | * happen even on a blocking fd. | |
315 | */ | |
316 | static ssize_t qemu_fill_buffer(QEMUFile *f) | |
093c455a EH |
317 | { |
318 | int len; | |
319 | int pending; | |
3d661c8a | 320 | Error *local_error = NULL; |
093c455a EH |
321 | |
322 | assert(!qemu_file_is_writable(f)); | |
323 | ||
324 | pending = f->buf_size - f->buf_index; | |
325 | if (pending > 0) { | |
326 | memmove(f->buf, f->buf + f->buf_index, pending); | |
327 | } | |
328 | f->buf_index = 0; | |
329 | f->buf_size = pending; | |
330 | ||
331 | len = f->ops->get_buffer(f->opaque, f->buf + pending, f->pos, | |
3d661c8a | 332 | IO_BUF_SIZE - pending, &local_error); |
093c455a EH |
333 | if (len > 0) { |
334 | f->buf_size += len; | |
335 | f->pos += len; | |
336 | } else if (len == 0) { | |
3d661c8a | 337 | qemu_file_set_error_obj(f, -EIO, local_error); |
093c455a | 338 | } else if (len != -EAGAIN) { |
3d661c8a YK |
339 | qemu_file_set_error_obj(f, len, local_error); |
340 | } else { | |
341 | error_free(local_error); | |
093c455a | 342 | } |
548f52ea DDAG |
343 | |
344 | return len; | |
093c455a EH |
345 | } |
346 | ||
093c455a EH |
347 | void qemu_update_position(QEMUFile *f, size_t size) |
348 | { | |
349 | f->pos += size; | |
350 | } | |
351 | ||
352 | /** Closes the file | |
353 | * | |
354 | * Returns negative error value if any error happened on previous operations or | |
355 | * while closing the file. Returns 0 or positive number on success. | |
356 | * | |
357 | * The meaning of return value on success depends on the specific backend | |
358 | * being used. | |
359 | */ | |
360 | int qemu_fclose(QEMUFile *f) | |
361 | { | |
362 | int ret; | |
363 | qemu_fflush(f); | |
364 | ret = qemu_file_get_error(f); | |
365 | ||
366 | if (f->ops->close) { | |
3d661c8a | 367 | int ret2 = f->ops->close(f->opaque, NULL); |
093c455a EH |
368 | if (ret >= 0) { |
369 | ret = ret2; | |
370 | } | |
371 | } | |
372 | /* If any error was spotted before closing, we should report it | |
373 | * instead of the close() return value. | |
374 | */ | |
375 | if (f->last_error) { | |
376 | ret = f->last_error; | |
377 | } | |
3d661c8a | 378 | error_free(f->last_error_obj); |
093c455a | 379 | g_free(f); |
9013dca5 | 380 | trace_qemu_file_fclose(); |
093c455a EH |
381 | return ret; |
382 | } | |
383 | ||
1bf57fb3 WY |
384 | /* |
385 | * Add buf to iovec. Do flush if iovec is full. | |
386 | * | |
387 | * Return values: | |
388 | * 1 iovec is full and flushed | |
389 | * 0 iovec is not flushed | |
390 | * | |
391 | */ | |
392 | static int add_to_iovec(QEMUFile *f, const uint8_t *buf, size_t size, | |
393 | bool may_free) | |
093c455a EH |
394 | { |
395 | /* check for adjacent buffer and coalesce them */ | |
396 | if (f->iovcnt > 0 && buf == f->iov[f->iovcnt - 1].iov_base + | |
53f09a10 PB |
397 | f->iov[f->iovcnt - 1].iov_len && |
398 | may_free == test_bit(f->iovcnt - 1, f->may_free)) | |
399 | { | |
093c455a EH |
400 | f->iov[f->iovcnt - 1].iov_len += size; |
401 | } else { | |
53f09a10 PB |
402 | if (may_free) { |
403 | set_bit(f->iovcnt, f->may_free); | |
404 | } | |
093c455a EH |
405 | f->iov[f->iovcnt].iov_base = (uint8_t *)buf; |
406 | f->iov[f->iovcnt++].iov_len = size; | |
407 | } | |
408 | ||
409 | if (f->iovcnt >= MAX_IOV_SIZE) { | |
410 | qemu_fflush(f); | |
1bf57fb3 WY |
411 | return 1; |
412 | } | |
413 | ||
414 | return 0; | |
415 | } | |
416 | ||
417 | static void add_buf_to_iovec(QEMUFile *f, size_t len) | |
418 | { | |
419 | if (!add_to_iovec(f, f->buf + f->buf_index, len, false)) { | |
420 | f->buf_index += len; | |
421 | if (f->buf_index == IO_BUF_SIZE) { | |
422 | qemu_fflush(f); | |
423 | } | |
093c455a EH |
424 | } |
425 | } | |
426 | ||
53f09a10 PB |
427 | void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, size_t size, |
428 | bool may_free) | |
093c455a | 429 | { |
093c455a EH |
430 | if (f->last_error) { |
431 | return; | |
432 | } | |
433 | ||
434 | f->bytes_xfer += size; | |
53f09a10 | 435 | add_to_iovec(f, buf, size, may_free); |
093c455a EH |
436 | } |
437 | ||
56f3835f | 438 | void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, size_t size) |
093c455a | 439 | { |
56f3835f | 440 | size_t l; |
093c455a EH |
441 | |
442 | if (f->last_error) { | |
443 | return; | |
444 | } | |
445 | ||
446 | while (size > 0) { | |
447 | l = IO_BUF_SIZE - f->buf_index; | |
448 | if (l > size) { | |
449 | l = size; | |
450 | } | |
451 | memcpy(f->buf + f->buf_index, buf, l); | |
452 | f->bytes_xfer += l; | |
1bf57fb3 | 453 | add_buf_to_iovec(f, l); |
093c455a EH |
454 | if (qemu_file_get_error(f)) { |
455 | break; | |
456 | } | |
457 | buf += l; | |
458 | size -= l; | |
459 | } | |
460 | } | |
461 | ||
462 | void qemu_put_byte(QEMUFile *f, int v) | |
463 | { | |
464 | if (f->last_error) { | |
465 | return; | |
466 | } | |
467 | ||
468 | f->buf[f->buf_index] = v; | |
469 | f->bytes_xfer++; | |
1bf57fb3 | 470 | add_buf_to_iovec(f, 1); |
093c455a EH |
471 | } |
472 | ||
473 | void qemu_file_skip(QEMUFile *f, int size) | |
474 | { | |
475 | if (f->buf_index + size <= f->buf_size) { | |
476 | f->buf_index += size; | |
477 | } | |
478 | } | |
479 | ||
548f52ea | 480 | /* |
7c1e52ba DDAG |
481 | * Read 'size' bytes from file (at 'offset') without moving the |
482 | * pointer and set 'buf' to point to that data. | |
548f52ea DDAG |
483 | * |
484 | * It will return size bytes unless there was an error, in which case it will | |
485 | * return as many as it managed to read (assuming blocking fd's which | |
486 | * all current QEMUFile are) | |
487 | */ | |
56f3835f | 488 | size_t qemu_peek_buffer(QEMUFile *f, uint8_t **buf, size_t size, size_t offset) |
093c455a | 489 | { |
56f3835f DDAG |
490 | ssize_t pending; |
491 | size_t index; | |
093c455a EH |
492 | |
493 | assert(!qemu_file_is_writable(f)); | |
548f52ea DDAG |
494 | assert(offset < IO_BUF_SIZE); |
495 | assert(size <= IO_BUF_SIZE - offset); | |
093c455a | 496 | |
548f52ea | 497 | /* The 1st byte to read from */ |
093c455a | 498 | index = f->buf_index + offset; |
548f52ea | 499 | /* The number of available bytes starting at index */ |
093c455a | 500 | pending = f->buf_size - index; |
548f52ea DDAG |
501 | |
502 | /* | |
503 | * qemu_fill_buffer might return just a few bytes, even when there isn't | |
504 | * an error, so loop collecting them until we get enough. | |
505 | */ | |
506 | while (pending < size) { | |
507 | int received = qemu_fill_buffer(f); | |
508 | ||
509 | if (received <= 0) { | |
510 | break; | |
511 | } | |
512 | ||
093c455a EH |
513 | index = f->buf_index + offset; |
514 | pending = f->buf_size - index; | |
515 | } | |
516 | ||
517 | if (pending <= 0) { | |
518 | return 0; | |
519 | } | |
520 | if (size > pending) { | |
521 | size = pending; | |
522 | } | |
523 | ||
7c1e52ba | 524 | *buf = f->buf + index; |
093c455a EH |
525 | return size; |
526 | } | |
527 | ||
548f52ea DDAG |
528 | /* |
529 | * Read 'size' bytes of data from the file into buf. | |
530 | * 'size' can be larger than the internal buffer. | |
531 | * | |
532 | * It will return size bytes unless there was an error, in which case it will | |
533 | * return as many as it managed to read (assuming blocking fd's which | |
534 | * all current QEMUFile are) | |
535 | */ | |
56f3835f | 536 | size_t qemu_get_buffer(QEMUFile *f, uint8_t *buf, size_t size) |
093c455a | 537 | { |
56f3835f DDAG |
538 | size_t pending = size; |
539 | size_t done = 0; | |
093c455a EH |
540 | |
541 | while (pending > 0) { | |
56f3835f | 542 | size_t res; |
7c1e52ba | 543 | uint8_t *src; |
093c455a | 544 | |
7c1e52ba | 545 | res = qemu_peek_buffer(f, &src, MIN(pending, IO_BUF_SIZE), 0); |
093c455a EH |
546 | if (res == 0) { |
547 | return done; | |
548 | } | |
7c1e52ba | 549 | memcpy(buf, src, res); |
093c455a EH |
550 | qemu_file_skip(f, res); |
551 | buf += res; | |
552 | pending -= res; | |
553 | done += res; | |
554 | } | |
555 | return done; | |
556 | } | |
557 | ||
9504fb51 DDAG |
558 | /* |
559 | * Read 'size' bytes of data from the file. | |
560 | * 'size' can be larger than the internal buffer. | |
561 | * | |
562 | * The data: | |
563 | * may be held on an internal buffer (in which case *buf is updated | |
564 | * to point to it) that is valid until the next qemu_file operation. | |
565 | * OR | |
566 | * will be copied to the *buf that was passed in. | |
567 | * | |
568 | * The code tries to avoid the copy if possible. | |
569 | * | |
570 | * It will return size bytes unless there was an error, in which case it will | |
571 | * return as many as it managed to read (assuming blocking fd's which | |
572 | * all current QEMUFile are) | |
573 | * | |
574 | * Note: Since **buf may get changed, the caller should take care to | |
575 | * keep a pointer to the original buffer if it needs to deallocate it. | |
576 | */ | |
577 | size_t qemu_get_buffer_in_place(QEMUFile *f, uint8_t **buf, size_t size) | |
578 | { | |
579 | if (size < IO_BUF_SIZE) { | |
580 | size_t res; | |
581 | uint8_t *src; | |
582 | ||
583 | res = qemu_peek_buffer(f, &src, size, 0); | |
584 | ||
585 | if (res == size) { | |
586 | qemu_file_skip(f, res); | |
587 | *buf = src; | |
588 | return res; | |
589 | } | |
590 | } | |
591 | ||
592 | return qemu_get_buffer(f, *buf, size); | |
593 | } | |
594 | ||
548f52ea DDAG |
595 | /* |
596 | * Peeks a single byte from the buffer; this isn't guaranteed to work if | |
597 | * offset leaves a gap after the previous read/peeked data. | |
598 | */ | |
093c455a EH |
599 | int qemu_peek_byte(QEMUFile *f, int offset) |
600 | { | |
601 | int index = f->buf_index + offset; | |
602 | ||
603 | assert(!qemu_file_is_writable(f)); | |
548f52ea | 604 | assert(offset < IO_BUF_SIZE); |
093c455a EH |
605 | |
606 | if (index >= f->buf_size) { | |
607 | qemu_fill_buffer(f); | |
608 | index = f->buf_index + offset; | |
609 | if (index >= f->buf_size) { | |
610 | return 0; | |
611 | } | |
612 | } | |
613 | return f->buf[index]; | |
614 | } | |
615 | ||
616 | int qemu_get_byte(QEMUFile *f) | |
617 | { | |
618 | int result; | |
619 | ||
620 | result = qemu_peek_byte(f, 0); | |
621 | qemu_file_skip(f, 1); | |
622 | return result; | |
623 | } | |
624 | ||
97221400 AG |
625 | int64_t qemu_ftell_fast(QEMUFile *f) |
626 | { | |
627 | int64_t ret = f->pos; | |
628 | int i; | |
629 | ||
11808bb0 DB |
630 | for (i = 0; i < f->iovcnt; i++) { |
631 | ret += f->iov[i].iov_len; | |
97221400 AG |
632 | } |
633 | ||
634 | return ret; | |
635 | } | |
636 | ||
093c455a EH |
637 | int64_t qemu_ftell(QEMUFile *f) |
638 | { | |
639 | qemu_fflush(f); | |
640 | return f->pos; | |
641 | } | |
642 | ||
643 | int qemu_file_rate_limit(QEMUFile *f) | |
644 | { | |
645 | if (qemu_file_get_error(f)) { | |
646 | return 1; | |
647 | } | |
648 | if (f->xfer_limit > 0 && f->bytes_xfer > f->xfer_limit) { | |
649 | return 1; | |
650 | } | |
651 | return 0; | |
652 | } | |
653 | ||
654 | int64_t qemu_file_get_rate_limit(QEMUFile *f) | |
655 | { | |
656 | return f->xfer_limit; | |
657 | } | |
658 | ||
659 | void qemu_file_set_rate_limit(QEMUFile *f, int64_t limit) | |
660 | { | |
661 | f->xfer_limit = limit; | |
662 | } | |
663 | ||
664 | void qemu_file_reset_rate_limit(QEMUFile *f) | |
665 | { | |
666 | f->bytes_xfer = 0; | |
667 | } | |
668 | ||
5d7d2558 IR |
669 | void qemu_file_update_transfer(QEMUFile *f, int64_t len) |
670 | { | |
671 | f->bytes_xfer += len; | |
672 | } | |
673 | ||
093c455a EH |
674 | void qemu_put_be16(QEMUFile *f, unsigned int v) |
675 | { | |
676 | qemu_put_byte(f, v >> 8); | |
677 | qemu_put_byte(f, v); | |
678 | } | |
679 | ||
680 | void qemu_put_be32(QEMUFile *f, unsigned int v) | |
681 | { | |
682 | qemu_put_byte(f, v >> 24); | |
683 | qemu_put_byte(f, v >> 16); | |
684 | qemu_put_byte(f, v >> 8); | |
685 | qemu_put_byte(f, v); | |
686 | } | |
687 | ||
688 | void qemu_put_be64(QEMUFile *f, uint64_t v) | |
689 | { | |
690 | qemu_put_be32(f, v >> 32); | |
691 | qemu_put_be32(f, v); | |
692 | } | |
693 | ||
694 | unsigned int qemu_get_be16(QEMUFile *f) | |
695 | { | |
696 | unsigned int v; | |
697 | v = qemu_get_byte(f) << 8; | |
698 | v |= qemu_get_byte(f); | |
699 | return v; | |
700 | } | |
701 | ||
702 | unsigned int qemu_get_be32(QEMUFile *f) | |
703 | { | |
704 | unsigned int v; | |
90d6a673 | 705 | v = (unsigned int)qemu_get_byte(f) << 24; |
093c455a EH |
706 | v |= qemu_get_byte(f) << 16; |
707 | v |= qemu_get_byte(f) << 8; | |
708 | v |= qemu_get_byte(f); | |
709 | return v; | |
710 | } | |
711 | ||
712 | uint64_t qemu_get_be64(QEMUFile *f) | |
713 | { | |
714 | uint64_t v; | |
715 | v = (uint64_t)qemu_get_be32(f) << 32; | |
716 | v |= qemu_get_be32(f); | |
717 | return v; | |
718 | } | |
44f0eadc | 719 | |
dcaf446e XG |
720 | /* return the size after compression, or negative value on error */ |
721 | static int qemu_compress_data(z_stream *stream, uint8_t *dest, size_t dest_len, | |
722 | const uint8_t *source, size_t source_len) | |
723 | { | |
724 | int err; | |
725 | ||
726 | err = deflateReset(stream); | |
727 | if (err != Z_OK) { | |
728 | return -1; | |
729 | } | |
730 | ||
731 | stream->avail_in = source_len; | |
732 | stream->next_in = (uint8_t *)source; | |
733 | stream->avail_out = dest_len; | |
734 | stream->next_out = dest; | |
735 | ||
736 | err = deflate(stream, Z_FINISH); | |
737 | if (err != Z_STREAM_END) { | |
738 | return -1; | |
739 | } | |
740 | ||
741 | return stream->next_out - dest; | |
742 | } | |
743 | ||
744 | /* Compress size bytes of data start at p and store the compressed | |
745 | * data to the buffer of f. | |
b3be2896 LL |
746 | * |
747 | * When f is not writable, return -1 if f has no space to save the | |
748 | * compressed data. | |
749 | * When f is wirtable and it has no space to save the compressed data, | |
750 | * do fflush first, if f still has no space to save the compressed | |
751 | * data, return -1. | |
44f0eadc | 752 | */ |
dcaf446e XG |
753 | ssize_t qemu_put_compression_data(QEMUFile *f, z_stream *stream, |
754 | const uint8_t *p, size_t size) | |
44f0eadc LL |
755 | { |
756 | ssize_t blen = IO_BUF_SIZE - f->buf_index - sizeof(int32_t); | |
757 | ||
758 | if (blen < compressBound(size)) { | |
b3be2896 LL |
759 | if (!qemu_file_is_writable(f)) { |
760 | return -1; | |
761 | } | |
762 | qemu_fflush(f); | |
763 | blen = IO_BUF_SIZE - sizeof(int32_t); | |
764 | if (blen < compressBound(size)) { | |
765 | return -1; | |
766 | } | |
44f0eadc | 767 | } |
dcaf446e XG |
768 | |
769 | blen = qemu_compress_data(stream, f->buf + f->buf_index + sizeof(int32_t), | |
770 | blen, p, size); | |
771 | if (blen < 0) { | |
34ab9e97 | 772 | return -1; |
44f0eadc | 773 | } |
34ab9e97 | 774 | |
44f0eadc | 775 | qemu_put_be32(f, blen); |
1bf57fb3 | 776 | add_buf_to_iovec(f, blen); |
44f0eadc LL |
777 | return blen + sizeof(int32_t); |
778 | } | |
779 | ||
780 | /* Put the data in the buffer of f_src to the buffer of f_des, and | |
781 | * then reset the buf_index of f_src to 0. | |
782 | */ | |
783 | ||
784 | int qemu_put_qemu_file(QEMUFile *f_des, QEMUFile *f_src) | |
785 | { | |
786 | int len = 0; | |
787 | ||
788 | if (f_src->buf_index > 0) { | |
789 | len = f_src->buf_index; | |
790 | qemu_put_buffer(f_des, f_src->buf, f_src->buf_index); | |
791 | f_src->buf_index = 0; | |
787d134f | 792 | f_src->iovcnt = 0; |
44f0eadc LL |
793 | } |
794 | return len; | |
795 | } | |
b3af1bc9 DDAG |
796 | |
797 | /* | |
798 | * Get a string whose length is determined by a single preceding byte | |
799 | * A preallocated 256 byte buffer must be passed in. | |
800 | * Returns: len on success and a 0 terminated string in the buffer | |
801 | * else 0 | |
802 | * (Note a 0 length string will return 0 either way) | |
803 | */ | |
804 | size_t qemu_get_counted_string(QEMUFile *f, char buf[256]) | |
805 | { | |
806 | size_t len = qemu_get_byte(f); | |
807 | size_t res = qemu_get_buffer(f, (uint8_t *)buf, len); | |
808 | ||
809 | buf[res] = 0; | |
810 | ||
811 | return res == len ? res : 0; | |
812 | } | |
a800cd5c | 813 | |
f0d64cb7 VSO |
814 | /* |
815 | * Put a string with one preceding byte containing its length. The length of | |
816 | * the string should be less than 256. | |
817 | */ | |
818 | void qemu_put_counted_string(QEMUFile *f, const char *str) | |
819 | { | |
820 | size_t len = strlen(str); | |
821 | ||
822 | assert(len < 256); | |
823 | qemu_put_byte(f, len); | |
824 | qemu_put_buffer(f, (const uint8_t *)str, len); | |
825 | } | |
826 | ||
a800cd5c DDAG |
827 | /* |
828 | * Set the blocking state of the QEMUFile. | |
829 | * Note: On some transports the OS only keeps a single blocking state for | |
830 | * both directions, and thus changing the blocking on the main | |
831 | * QEMUFile can also affect the return path. | |
832 | */ | |
833 | void qemu_file_set_blocking(QEMUFile *f, bool block) | |
834 | { | |
06ad5135 | 835 | if (f->ops->set_blocking) { |
3d661c8a | 836 | f->ops->set_blocking(f->opaque, block, NULL); |
a800cd5c DDAG |
837 | } |
838 | } |