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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 | * | |
204 | * If there is writev_buffer QEMUFileOps it uses it otherwise uses | |
baf51e77 DB |
205 | * put_buffer ops. This will flush all pending data. If data was |
206 | * only partially flushed, it will set an error state. | |
093c455a EH |
207 | */ |
208 | void qemu_fflush(QEMUFile *f) | |
209 | { | |
210 | ssize_t ret = 0; | |
baf51e77 | 211 | ssize_t expect = 0; |
3d661c8a | 212 | Error *local_error = NULL; |
093c455a EH |
213 | |
214 | if (!qemu_file_is_writable(f)) { | |
215 | return; | |
216 | } | |
217 | ||
11808bb0 DB |
218 | if (f->iovcnt > 0) { |
219 | expect = iov_size(f->iov, f->iovcnt); | |
3d661c8a YK |
220 | ret = f->ops->writev_buffer(f->opaque, f->iov, f->iovcnt, f->pos, |
221 | &local_error); | |
53f09a10 PB |
222 | |
223 | qemu_iovec_release_ram(f); | |
093c455a | 224 | } |
baf51e77 | 225 | |
093c455a EH |
226 | if (ret >= 0) { |
227 | f->pos += ret; | |
228 | } | |
baf51e77 DB |
229 | /* We expect the QEMUFile write impl to send the full |
230 | * data set we requested, so sanity check that. | |
231 | */ | |
232 | if (ret != expect) { | |
3d661c8a | 233 | qemu_file_set_error_obj(f, ret < 0 ? ret : -EIO, local_error); |
baf51e77 | 234 | } |
093c455a EH |
235 | f->buf_index = 0; |
236 | f->iovcnt = 0; | |
093c455a EH |
237 | } |
238 | ||
239 | void ram_control_before_iterate(QEMUFile *f, uint64_t flags) | |
240 | { | |
241 | int ret = 0; | |
242 | ||
0436e09f DB |
243 | if (f->hooks && f->hooks->before_ram_iterate) { |
244 | ret = f->hooks->before_ram_iterate(f, f->opaque, flags, NULL); | |
093c455a EH |
245 | if (ret < 0) { |
246 | qemu_file_set_error(f, ret); | |
247 | } | |
248 | } | |
249 | } | |
250 | ||
251 | void ram_control_after_iterate(QEMUFile *f, uint64_t flags) | |
252 | { | |
253 | int ret = 0; | |
254 | ||
0436e09f DB |
255 | if (f->hooks && f->hooks->after_ram_iterate) { |
256 | ret = f->hooks->after_ram_iterate(f, f->opaque, flags, NULL); | |
093c455a EH |
257 | if (ret < 0) { |
258 | qemu_file_set_error(f, ret); | |
259 | } | |
260 | } | |
261 | } | |
262 | ||
632e3a5c | 263 | void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data) |
093c455a EH |
264 | { |
265 | int ret = -EINVAL; | |
266 | ||
0436e09f DB |
267 | if (f->hooks && f->hooks->hook_ram_load) { |
268 | ret = f->hooks->hook_ram_load(f, f->opaque, flags, data); | |
093c455a EH |
269 | if (ret < 0) { |
270 | qemu_file_set_error(f, ret); | |
271 | } | |
272 | } else { | |
632e3a5c DDAG |
273 | /* |
274 | * Hook is a hook specifically requested by the source sending a flag | |
275 | * that expects there to be a hook on the destination. | |
276 | */ | |
277 | if (flags == RAM_CONTROL_HOOK) { | |
278 | qemu_file_set_error(f, ret); | |
279 | } | |
093c455a EH |
280 | } |
281 | } | |
282 | ||
283 | size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset, | |
6e1dea46 JQ |
284 | ram_addr_t offset, size_t size, |
285 | uint64_t *bytes_sent) | |
093c455a | 286 | { |
0436e09f DB |
287 | if (f->hooks && f->hooks->save_page) { |
288 | int ret = f->hooks->save_page(f, f->opaque, block_offset, | |
289 | offset, size, bytes_sent); | |
ccb7e1b5 LC |
290 | if (ret != RAM_SAVE_CONTROL_NOT_SUPP) { |
291 | f->bytes_xfer += size; | |
292 | } | |
293 | ||
294 | if (ret != RAM_SAVE_CONTROL_DELAYED && | |
295 | ret != RAM_SAVE_CONTROL_NOT_SUPP) { | |
093c455a EH |
296 | if (bytes_sent && *bytes_sent > 0) { |
297 | qemu_update_position(f, *bytes_sent); | |
298 | } else if (ret < 0) { | |
299 | qemu_file_set_error(f, ret); | |
300 | } | |
301 | } | |
302 | ||
303 | return ret; | |
304 | } | |
305 | ||
306 | return RAM_SAVE_CONTROL_NOT_SUPP; | |
307 | } | |
308 | ||
548f52ea DDAG |
309 | /* |
310 | * Attempt to fill the buffer from the underlying file | |
311 | * Returns the number of bytes read, or negative value for an error. | |
312 | * | |
313 | * Note that it can return a partially full buffer even in a not error/not EOF | |
314 | * case if the underlying file descriptor gives a short read, and that can | |
315 | * happen even on a blocking fd. | |
316 | */ | |
317 | static ssize_t qemu_fill_buffer(QEMUFile *f) | |
093c455a EH |
318 | { |
319 | int len; | |
320 | int pending; | |
3d661c8a | 321 | Error *local_error = NULL; |
093c455a EH |
322 | |
323 | assert(!qemu_file_is_writable(f)); | |
324 | ||
325 | pending = f->buf_size - f->buf_index; | |
326 | if (pending > 0) { | |
327 | memmove(f->buf, f->buf + f->buf_index, pending); | |
328 | } | |
329 | f->buf_index = 0; | |
330 | f->buf_size = pending; | |
331 | ||
332 | len = f->ops->get_buffer(f->opaque, f->buf + pending, f->pos, | |
3d661c8a | 333 | IO_BUF_SIZE - pending, &local_error); |
093c455a EH |
334 | if (len > 0) { |
335 | f->buf_size += len; | |
336 | f->pos += len; | |
337 | } else if (len == 0) { | |
3d661c8a | 338 | qemu_file_set_error_obj(f, -EIO, local_error); |
093c455a | 339 | } else if (len != -EAGAIN) { |
3d661c8a YK |
340 | qemu_file_set_error_obj(f, len, local_error); |
341 | } else { | |
342 | error_free(local_error); | |
093c455a | 343 | } |
548f52ea DDAG |
344 | |
345 | return len; | |
093c455a EH |
346 | } |
347 | ||
093c455a EH |
348 | void qemu_update_position(QEMUFile *f, size_t size) |
349 | { | |
350 | f->pos += size; | |
351 | } | |
352 | ||
353 | /** Closes the file | |
354 | * | |
355 | * Returns negative error value if any error happened on previous operations or | |
356 | * while closing the file. Returns 0 or positive number on success. | |
357 | * | |
358 | * The meaning of return value on success depends on the specific backend | |
359 | * being used. | |
360 | */ | |
361 | int qemu_fclose(QEMUFile *f) | |
362 | { | |
363 | int ret; | |
364 | qemu_fflush(f); | |
365 | ret = qemu_file_get_error(f); | |
366 | ||
367 | if (f->ops->close) { | |
3d661c8a | 368 | int ret2 = f->ops->close(f->opaque, NULL); |
093c455a EH |
369 | if (ret >= 0) { |
370 | ret = ret2; | |
371 | } | |
372 | } | |
373 | /* If any error was spotted before closing, we should report it | |
374 | * instead of the close() return value. | |
375 | */ | |
376 | if (f->last_error) { | |
377 | ret = f->last_error; | |
378 | } | |
3d661c8a | 379 | error_free(f->last_error_obj); |
093c455a | 380 | g_free(f); |
9013dca5 | 381 | trace_qemu_file_fclose(); |
093c455a EH |
382 | return ret; |
383 | } | |
384 | ||
53f09a10 PB |
385 | static void add_to_iovec(QEMUFile *f, const uint8_t *buf, size_t size, |
386 | bool may_free) | |
093c455a EH |
387 | { |
388 | /* check for adjacent buffer and coalesce them */ | |
389 | if (f->iovcnt > 0 && buf == f->iov[f->iovcnt - 1].iov_base + | |
53f09a10 PB |
390 | f->iov[f->iovcnt - 1].iov_len && |
391 | may_free == test_bit(f->iovcnt - 1, f->may_free)) | |
392 | { | |
093c455a EH |
393 | f->iov[f->iovcnt - 1].iov_len += size; |
394 | } else { | |
53f09a10 PB |
395 | if (may_free) { |
396 | set_bit(f->iovcnt, f->may_free); | |
397 | } | |
093c455a EH |
398 | f->iov[f->iovcnt].iov_base = (uint8_t *)buf; |
399 | f->iov[f->iovcnt++].iov_len = size; | |
400 | } | |
401 | ||
402 | if (f->iovcnt >= MAX_IOV_SIZE) { | |
403 | qemu_fflush(f); | |
404 | } | |
405 | } | |
406 | ||
53f09a10 PB |
407 | void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, size_t size, |
408 | bool may_free) | |
093c455a | 409 | { |
093c455a EH |
410 | if (f->last_error) { |
411 | return; | |
412 | } | |
413 | ||
414 | f->bytes_xfer += size; | |
53f09a10 | 415 | add_to_iovec(f, buf, size, may_free); |
093c455a EH |
416 | } |
417 | ||
56f3835f | 418 | void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, size_t size) |
093c455a | 419 | { |
56f3835f | 420 | size_t l; |
093c455a EH |
421 | |
422 | if (f->last_error) { | |
423 | return; | |
424 | } | |
425 | ||
426 | while (size > 0) { | |
427 | l = IO_BUF_SIZE - f->buf_index; | |
428 | if (l > size) { | |
429 | l = size; | |
430 | } | |
431 | memcpy(f->buf + f->buf_index, buf, l); | |
432 | f->bytes_xfer += l; | |
53f09a10 | 433 | add_to_iovec(f, f->buf + f->buf_index, l, false); |
093c455a EH |
434 | f->buf_index += l; |
435 | if (f->buf_index == IO_BUF_SIZE) { | |
436 | qemu_fflush(f); | |
437 | } | |
438 | if (qemu_file_get_error(f)) { | |
439 | break; | |
440 | } | |
441 | buf += l; | |
442 | size -= l; | |
443 | } | |
444 | } | |
445 | ||
446 | void qemu_put_byte(QEMUFile *f, int v) | |
447 | { | |
448 | if (f->last_error) { | |
449 | return; | |
450 | } | |
451 | ||
452 | f->buf[f->buf_index] = v; | |
453 | f->bytes_xfer++; | |
53f09a10 | 454 | add_to_iovec(f, f->buf + f->buf_index, 1, false); |
093c455a EH |
455 | f->buf_index++; |
456 | if (f->buf_index == IO_BUF_SIZE) { | |
457 | qemu_fflush(f); | |
458 | } | |
459 | } | |
460 | ||
461 | void qemu_file_skip(QEMUFile *f, int size) | |
462 | { | |
463 | if (f->buf_index + size <= f->buf_size) { | |
464 | f->buf_index += size; | |
465 | } | |
466 | } | |
467 | ||
548f52ea | 468 | /* |
7c1e52ba DDAG |
469 | * Read 'size' bytes from file (at 'offset') without moving the |
470 | * pointer and set 'buf' to point to that data. | |
548f52ea DDAG |
471 | * |
472 | * It will return size bytes unless there was an error, in which case it will | |
473 | * return as many as it managed to read (assuming blocking fd's which | |
474 | * all current QEMUFile are) | |
475 | */ | |
56f3835f | 476 | size_t qemu_peek_buffer(QEMUFile *f, uint8_t **buf, size_t size, size_t offset) |
093c455a | 477 | { |
56f3835f DDAG |
478 | ssize_t pending; |
479 | size_t index; | |
093c455a EH |
480 | |
481 | assert(!qemu_file_is_writable(f)); | |
548f52ea DDAG |
482 | assert(offset < IO_BUF_SIZE); |
483 | assert(size <= IO_BUF_SIZE - offset); | |
093c455a | 484 | |
548f52ea | 485 | /* The 1st byte to read from */ |
093c455a | 486 | index = f->buf_index + offset; |
548f52ea | 487 | /* The number of available bytes starting at index */ |
093c455a | 488 | pending = f->buf_size - index; |
548f52ea DDAG |
489 | |
490 | /* | |
491 | * qemu_fill_buffer might return just a few bytes, even when there isn't | |
492 | * an error, so loop collecting them until we get enough. | |
493 | */ | |
494 | while (pending < size) { | |
495 | int received = qemu_fill_buffer(f); | |
496 | ||
497 | if (received <= 0) { | |
498 | break; | |
499 | } | |
500 | ||
093c455a EH |
501 | index = f->buf_index + offset; |
502 | pending = f->buf_size - index; | |
503 | } | |
504 | ||
505 | if (pending <= 0) { | |
506 | return 0; | |
507 | } | |
508 | if (size > pending) { | |
509 | size = pending; | |
510 | } | |
511 | ||
7c1e52ba | 512 | *buf = f->buf + index; |
093c455a EH |
513 | return size; |
514 | } | |
515 | ||
548f52ea DDAG |
516 | /* |
517 | * Read 'size' bytes of data from the file into buf. | |
518 | * 'size' can be larger than the internal buffer. | |
519 | * | |
520 | * It will return size bytes unless there was an error, in which case it will | |
521 | * return as many as it managed to read (assuming blocking fd's which | |
522 | * all current QEMUFile are) | |
523 | */ | |
56f3835f | 524 | size_t qemu_get_buffer(QEMUFile *f, uint8_t *buf, size_t size) |
093c455a | 525 | { |
56f3835f DDAG |
526 | size_t pending = size; |
527 | size_t done = 0; | |
093c455a EH |
528 | |
529 | while (pending > 0) { | |
56f3835f | 530 | size_t res; |
7c1e52ba | 531 | uint8_t *src; |
093c455a | 532 | |
7c1e52ba | 533 | res = qemu_peek_buffer(f, &src, MIN(pending, IO_BUF_SIZE), 0); |
093c455a EH |
534 | if (res == 0) { |
535 | return done; | |
536 | } | |
7c1e52ba | 537 | memcpy(buf, src, res); |
093c455a EH |
538 | qemu_file_skip(f, res); |
539 | buf += res; | |
540 | pending -= res; | |
541 | done += res; | |
542 | } | |
543 | return done; | |
544 | } | |
545 | ||
9504fb51 DDAG |
546 | /* |
547 | * Read 'size' bytes of data from the file. | |
548 | * 'size' can be larger than the internal buffer. | |
549 | * | |
550 | * The data: | |
551 | * may be held on an internal buffer (in which case *buf is updated | |
552 | * to point to it) that is valid until the next qemu_file operation. | |
553 | * OR | |
554 | * will be copied to the *buf that was passed in. | |
555 | * | |
556 | * The code tries to avoid the copy if possible. | |
557 | * | |
558 | * It will return size bytes unless there was an error, in which case it will | |
559 | * return as many as it managed to read (assuming blocking fd's which | |
560 | * all current QEMUFile are) | |
561 | * | |
562 | * Note: Since **buf may get changed, the caller should take care to | |
563 | * keep a pointer to the original buffer if it needs to deallocate it. | |
564 | */ | |
565 | size_t qemu_get_buffer_in_place(QEMUFile *f, uint8_t **buf, size_t size) | |
566 | { | |
567 | if (size < IO_BUF_SIZE) { | |
568 | size_t res; | |
569 | uint8_t *src; | |
570 | ||
571 | res = qemu_peek_buffer(f, &src, size, 0); | |
572 | ||
573 | if (res == size) { | |
574 | qemu_file_skip(f, res); | |
575 | *buf = src; | |
576 | return res; | |
577 | } | |
578 | } | |
579 | ||
580 | return qemu_get_buffer(f, *buf, size); | |
581 | } | |
582 | ||
548f52ea DDAG |
583 | /* |
584 | * Peeks a single byte from the buffer; this isn't guaranteed to work if | |
585 | * offset leaves a gap after the previous read/peeked data. | |
586 | */ | |
093c455a EH |
587 | int qemu_peek_byte(QEMUFile *f, int offset) |
588 | { | |
589 | int index = f->buf_index + offset; | |
590 | ||
591 | assert(!qemu_file_is_writable(f)); | |
548f52ea | 592 | assert(offset < IO_BUF_SIZE); |
093c455a EH |
593 | |
594 | if (index >= f->buf_size) { | |
595 | qemu_fill_buffer(f); | |
596 | index = f->buf_index + offset; | |
597 | if (index >= f->buf_size) { | |
598 | return 0; | |
599 | } | |
600 | } | |
601 | return f->buf[index]; | |
602 | } | |
603 | ||
604 | int qemu_get_byte(QEMUFile *f) | |
605 | { | |
606 | int result; | |
607 | ||
608 | result = qemu_peek_byte(f, 0); | |
609 | qemu_file_skip(f, 1); | |
610 | return result; | |
611 | } | |
612 | ||
97221400 AG |
613 | int64_t qemu_ftell_fast(QEMUFile *f) |
614 | { | |
615 | int64_t ret = f->pos; | |
616 | int i; | |
617 | ||
11808bb0 DB |
618 | for (i = 0; i < f->iovcnt; i++) { |
619 | ret += f->iov[i].iov_len; | |
97221400 AG |
620 | } |
621 | ||
622 | return ret; | |
623 | } | |
624 | ||
093c455a EH |
625 | int64_t qemu_ftell(QEMUFile *f) |
626 | { | |
627 | qemu_fflush(f); | |
628 | return f->pos; | |
629 | } | |
630 | ||
631 | int qemu_file_rate_limit(QEMUFile *f) | |
632 | { | |
633 | if (qemu_file_get_error(f)) { | |
634 | return 1; | |
635 | } | |
636 | if (f->xfer_limit > 0 && f->bytes_xfer > f->xfer_limit) { | |
637 | return 1; | |
638 | } | |
639 | return 0; | |
640 | } | |
641 | ||
642 | int64_t qemu_file_get_rate_limit(QEMUFile *f) | |
643 | { | |
644 | return f->xfer_limit; | |
645 | } | |
646 | ||
647 | void qemu_file_set_rate_limit(QEMUFile *f, int64_t limit) | |
648 | { | |
649 | f->xfer_limit = limit; | |
650 | } | |
651 | ||
652 | void qemu_file_reset_rate_limit(QEMUFile *f) | |
653 | { | |
654 | f->bytes_xfer = 0; | |
655 | } | |
656 | ||
657 | void qemu_put_be16(QEMUFile *f, unsigned int v) | |
658 | { | |
659 | qemu_put_byte(f, v >> 8); | |
660 | qemu_put_byte(f, v); | |
661 | } | |
662 | ||
663 | void qemu_put_be32(QEMUFile *f, unsigned int v) | |
664 | { | |
665 | qemu_put_byte(f, v >> 24); | |
666 | qemu_put_byte(f, v >> 16); | |
667 | qemu_put_byte(f, v >> 8); | |
668 | qemu_put_byte(f, v); | |
669 | } | |
670 | ||
671 | void qemu_put_be64(QEMUFile *f, uint64_t v) | |
672 | { | |
673 | qemu_put_be32(f, v >> 32); | |
674 | qemu_put_be32(f, v); | |
675 | } | |
676 | ||
677 | unsigned int qemu_get_be16(QEMUFile *f) | |
678 | { | |
679 | unsigned int v; | |
680 | v = qemu_get_byte(f) << 8; | |
681 | v |= qemu_get_byte(f); | |
682 | return v; | |
683 | } | |
684 | ||
685 | unsigned int qemu_get_be32(QEMUFile *f) | |
686 | { | |
687 | unsigned int v; | |
90d6a673 | 688 | v = (unsigned int)qemu_get_byte(f) << 24; |
093c455a EH |
689 | v |= qemu_get_byte(f) << 16; |
690 | v |= qemu_get_byte(f) << 8; | |
691 | v |= qemu_get_byte(f); | |
692 | return v; | |
693 | } | |
694 | ||
695 | uint64_t qemu_get_be64(QEMUFile *f) | |
696 | { | |
697 | uint64_t v; | |
698 | v = (uint64_t)qemu_get_be32(f) << 32; | |
699 | v |= qemu_get_be32(f); | |
700 | return v; | |
701 | } | |
44f0eadc | 702 | |
dcaf446e XG |
703 | /* return the size after compression, or negative value on error */ |
704 | static int qemu_compress_data(z_stream *stream, uint8_t *dest, size_t dest_len, | |
705 | const uint8_t *source, size_t source_len) | |
706 | { | |
707 | int err; | |
708 | ||
709 | err = deflateReset(stream); | |
710 | if (err != Z_OK) { | |
711 | return -1; | |
712 | } | |
713 | ||
714 | stream->avail_in = source_len; | |
715 | stream->next_in = (uint8_t *)source; | |
716 | stream->avail_out = dest_len; | |
717 | stream->next_out = dest; | |
718 | ||
719 | err = deflate(stream, Z_FINISH); | |
720 | if (err != Z_STREAM_END) { | |
721 | return -1; | |
722 | } | |
723 | ||
724 | return stream->next_out - dest; | |
725 | } | |
726 | ||
727 | /* Compress size bytes of data start at p and store the compressed | |
728 | * data to the buffer of f. | |
b3be2896 LL |
729 | * |
730 | * When f is not writable, return -1 if f has no space to save the | |
731 | * compressed data. | |
732 | * When f is wirtable and it has no space to save the compressed data, | |
733 | * do fflush first, if f still has no space to save the compressed | |
734 | * data, return -1. | |
44f0eadc | 735 | */ |
dcaf446e XG |
736 | ssize_t qemu_put_compression_data(QEMUFile *f, z_stream *stream, |
737 | const uint8_t *p, size_t size) | |
44f0eadc LL |
738 | { |
739 | ssize_t blen = IO_BUF_SIZE - f->buf_index - sizeof(int32_t); | |
740 | ||
741 | if (blen < compressBound(size)) { | |
b3be2896 LL |
742 | if (!qemu_file_is_writable(f)) { |
743 | return -1; | |
744 | } | |
745 | qemu_fflush(f); | |
746 | blen = IO_BUF_SIZE - sizeof(int32_t); | |
747 | if (blen < compressBound(size)) { | |
748 | return -1; | |
749 | } | |
44f0eadc | 750 | } |
dcaf446e XG |
751 | |
752 | blen = qemu_compress_data(stream, f->buf + f->buf_index + sizeof(int32_t), | |
753 | blen, p, size); | |
754 | if (blen < 0) { | |
34ab9e97 | 755 | return -1; |
44f0eadc | 756 | } |
34ab9e97 | 757 | |
44f0eadc | 758 | qemu_put_be32(f, blen); |
b3be2896 | 759 | if (f->ops->writev_buffer) { |
53f09a10 | 760 | add_to_iovec(f, f->buf + f->buf_index, blen, false); |
b3be2896 | 761 | } |
44f0eadc | 762 | f->buf_index += blen; |
b3be2896 LL |
763 | if (f->buf_index == IO_BUF_SIZE) { |
764 | qemu_fflush(f); | |
765 | } | |
44f0eadc LL |
766 | return blen + sizeof(int32_t); |
767 | } | |
768 | ||
769 | /* Put the data in the buffer of f_src to the buffer of f_des, and | |
770 | * then reset the buf_index of f_src to 0. | |
771 | */ | |
772 | ||
773 | int qemu_put_qemu_file(QEMUFile *f_des, QEMUFile *f_src) | |
774 | { | |
775 | int len = 0; | |
776 | ||
777 | if (f_src->buf_index > 0) { | |
778 | len = f_src->buf_index; | |
779 | qemu_put_buffer(f_des, f_src->buf, f_src->buf_index); | |
780 | f_src->buf_index = 0; | |
787d134f | 781 | f_src->iovcnt = 0; |
44f0eadc LL |
782 | } |
783 | return len; | |
784 | } | |
b3af1bc9 DDAG |
785 | |
786 | /* | |
787 | * Get a string whose length is determined by a single preceding byte | |
788 | * A preallocated 256 byte buffer must be passed in. | |
789 | * Returns: len on success and a 0 terminated string in the buffer | |
790 | * else 0 | |
791 | * (Note a 0 length string will return 0 either way) | |
792 | */ | |
793 | size_t qemu_get_counted_string(QEMUFile *f, char buf[256]) | |
794 | { | |
795 | size_t len = qemu_get_byte(f); | |
796 | size_t res = qemu_get_buffer(f, (uint8_t *)buf, len); | |
797 | ||
798 | buf[res] = 0; | |
799 | ||
800 | return res == len ? res : 0; | |
801 | } | |
a800cd5c | 802 | |
f0d64cb7 VSO |
803 | /* |
804 | * Put a string with one preceding byte containing its length. The length of | |
805 | * the string should be less than 256. | |
806 | */ | |
807 | void qemu_put_counted_string(QEMUFile *f, const char *str) | |
808 | { | |
809 | size_t len = strlen(str); | |
810 | ||
811 | assert(len < 256); | |
812 | qemu_put_byte(f, len); | |
813 | qemu_put_buffer(f, (const uint8_t *)str, len); | |
814 | } | |
815 | ||
a800cd5c DDAG |
816 | /* |
817 | * Set the blocking state of the QEMUFile. | |
818 | * Note: On some transports the OS only keeps a single blocking state for | |
819 | * both directions, and thus changing the blocking on the main | |
820 | * QEMUFile can also affect the return path. | |
821 | */ | |
822 | void qemu_file_set_blocking(QEMUFile *f, bool block) | |
823 | { | |
06ad5135 | 824 | if (f->ops->set_blocking) { |
3d661c8a | 825 | f->ops->set_blocking(f->opaque, block, NULL); |
a800cd5c DDAG |
826 | } |
827 | } |