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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; |
a555b809 JQ |
56 | /* has the file has been shutdown */ |
57 | bool shutdown; | |
a24939f2 DB |
58 | }; |
59 | ||
e1a8c9b6 DDAG |
60 | /* |
61 | * Stop a file from being read/written - not all backing files can do this | |
62 | * typically only sockets can. | |
63 | */ | |
64 | int qemu_file_shutdown(QEMUFile *f) | |
65 | { | |
a555b809 JQ |
66 | int ret; |
67 | ||
68 | f->shutdown = true; | |
e1a8c9b6 DDAG |
69 | if (!f->ops->shut_down) { |
70 | return -ENOSYS; | |
71 | } | |
a555b809 JQ |
72 | ret = f->ops->shut_down(f->opaque, true, true, NULL); |
73 | ||
74 | if (!f->last_error) { | |
75 | qemu_file_set_error(f, -EIO); | |
76 | } | |
77 | return ret; | |
e1a8c9b6 DDAG |
78 | } |
79 | ||
adc468e9 DDAG |
80 | /* |
81 | * Result: QEMUFile* for a 'return path' for comms in the opposite direction | |
82 | * NULL if not available | |
83 | */ | |
84 | QEMUFile *qemu_file_get_return_path(QEMUFile *f) | |
85 | { | |
86 | if (!f->ops->get_return_path) { | |
87 | return NULL; | |
88 | } | |
89 | return f->ops->get_return_path(f->opaque); | |
90 | } | |
91 | ||
093c455a EH |
92 | bool qemu_file_mode_is_not_valid(const char *mode) |
93 | { | |
94 | if (mode == NULL || | |
95 | (mode[0] != 'r' && mode[0] != 'w') || | |
96 | mode[1] != 'b' || mode[2] != 0) { | |
97 | fprintf(stderr, "qemu_fopen: Argument validity check failed\n"); | |
98 | return true; | |
99 | } | |
100 | ||
101 | return false; | |
102 | } | |
103 | ||
093c455a EH |
104 | QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops) |
105 | { | |
106 | QEMUFile *f; | |
107 | ||
97f3ad35 | 108 | f = g_new0(QEMUFile, 1); |
093c455a EH |
109 | |
110 | f->opaque = opaque; | |
111 | f->ops = ops; | |
112 | return f; | |
113 | } | |
114 | ||
0436e09f DB |
115 | |
116 | void qemu_file_set_hooks(QEMUFile *f, const QEMUFileHooks *hooks) | |
117 | { | |
118 | f->hooks = hooks; | |
119 | } | |
120 | ||
093c455a | 121 | /* |
3d661c8a | 122 | * Get last error for stream f with optional Error* |
093c455a EH |
123 | * |
124 | * Return negative error value if there has been an error on previous | |
125 | * operations, return 0 if no error happened. | |
3d661c8a YK |
126 | * Optional, it returns Error* in errp, but it may be NULL even if return value |
127 | * is not 0. | |
093c455a EH |
128 | * |
129 | */ | |
3d661c8a | 130 | int qemu_file_get_error_obj(QEMUFile *f, Error **errp) |
093c455a | 131 | { |
3d661c8a YK |
132 | if (errp) { |
133 | *errp = f->last_error_obj ? error_copy(f->last_error_obj) : NULL; | |
134 | } | |
093c455a EH |
135 | return f->last_error; |
136 | } | |
137 | ||
3d661c8a YK |
138 | /* |
139 | * Set the last error for stream f with optional Error* | |
140 | */ | |
141 | void qemu_file_set_error_obj(QEMUFile *f, int ret, Error *err) | |
093c455a | 142 | { |
3d661c8a | 143 | if (f->last_error == 0 && ret) { |
093c455a | 144 | f->last_error = ret; |
3d661c8a YK |
145 | error_propagate(&f->last_error_obj, err); |
146 | } else if (err) { | |
147 | error_report_err(err); | |
093c455a EH |
148 | } |
149 | } | |
150 | ||
3d661c8a YK |
151 | /* |
152 | * Get last error for stream f | |
153 | * | |
154 | * Return negative error value if there has been an error on previous | |
155 | * operations, return 0 if no error happened. | |
156 | * | |
157 | */ | |
158 | int qemu_file_get_error(QEMUFile *f) | |
159 | { | |
160 | return qemu_file_get_error_obj(f, NULL); | |
161 | } | |
162 | ||
163 | /* | |
164 | * Set the last error for stream f | |
165 | */ | |
166 | void qemu_file_set_error(QEMUFile *f, int ret) | |
167 | { | |
168 | qemu_file_set_error_obj(f, ret, NULL); | |
169 | } | |
170 | ||
e68dd365 | 171 | bool qemu_file_is_writable(QEMUFile *f) |
093c455a | 172 | { |
11808bb0 | 173 | return f->ops->writev_buffer; |
093c455a EH |
174 | } |
175 | ||
53f09a10 PB |
176 | static void qemu_iovec_release_ram(QEMUFile *f) |
177 | { | |
178 | struct iovec iov; | |
179 | unsigned long idx; | |
180 | ||
181 | /* Find and release all the contiguous memory ranges marked as may_free. */ | |
182 | idx = find_next_bit(f->may_free, f->iovcnt, 0); | |
183 | if (idx >= f->iovcnt) { | |
184 | return; | |
185 | } | |
186 | iov = f->iov[idx]; | |
187 | ||
188 | /* The madvise() in the loop is called for iov within a continuous range and | |
189 | * then reinitialize the iov. And in the end, madvise() is called for the | |
190 | * last iov. | |
191 | */ | |
192 | while ((idx = find_next_bit(f->may_free, f->iovcnt, idx + 1)) < f->iovcnt) { | |
193 | /* check for adjacent buffer and coalesce them */ | |
194 | if (iov.iov_base + iov.iov_len == f->iov[idx].iov_base) { | |
195 | iov.iov_len += f->iov[idx].iov_len; | |
196 | continue; | |
197 | } | |
198 | if (qemu_madvise(iov.iov_base, iov.iov_len, QEMU_MADV_DONTNEED) < 0) { | |
199 | error_report("migrate: madvise DONTNEED failed %p %zd: %s", | |
200 | iov.iov_base, iov.iov_len, strerror(errno)); | |
201 | } | |
202 | iov = f->iov[idx]; | |
203 | } | |
204 | if (qemu_madvise(iov.iov_base, iov.iov_len, QEMU_MADV_DONTNEED) < 0) { | |
205 | error_report("migrate: madvise DONTNEED failed %p %zd: %s", | |
206 | iov.iov_base, iov.iov_len, strerror(errno)); | |
207 | } | |
208 | memset(f->may_free, 0, sizeof(f->may_free)); | |
209 | } | |
210 | ||
093c455a EH |
211 | /** |
212 | * Flushes QEMUFile buffer | |
213 | * | |
3b348706 DDAG |
214 | * This will flush all pending data. If data was only partially flushed, it |
215 | * will set an error state. | |
093c455a EH |
216 | */ |
217 | void qemu_fflush(QEMUFile *f) | |
218 | { | |
219 | ssize_t ret = 0; | |
baf51e77 | 220 | ssize_t expect = 0; |
3d661c8a | 221 | Error *local_error = NULL; |
093c455a EH |
222 | |
223 | if (!qemu_file_is_writable(f)) { | |
224 | return; | |
225 | } | |
226 | ||
a555b809 JQ |
227 | if (f->shutdown) { |
228 | return; | |
229 | } | |
11808bb0 DB |
230 | if (f->iovcnt > 0) { |
231 | expect = iov_size(f->iov, f->iovcnt); | |
3d661c8a YK |
232 | ret = f->ops->writev_buffer(f->opaque, f->iov, f->iovcnt, f->pos, |
233 | &local_error); | |
53f09a10 PB |
234 | |
235 | qemu_iovec_release_ram(f); | |
093c455a | 236 | } |
baf51e77 | 237 | |
093c455a EH |
238 | if (ret >= 0) { |
239 | f->pos += ret; | |
240 | } | |
baf51e77 DB |
241 | /* We expect the QEMUFile write impl to send the full |
242 | * data set we requested, so sanity check that. | |
243 | */ | |
244 | if (ret != expect) { | |
3d661c8a | 245 | qemu_file_set_error_obj(f, ret < 0 ? ret : -EIO, local_error); |
baf51e77 | 246 | } |
093c455a EH |
247 | f->buf_index = 0; |
248 | f->iovcnt = 0; | |
093c455a EH |
249 | } |
250 | ||
251 | void ram_control_before_iterate(QEMUFile *f, uint64_t flags) | |
252 | { | |
253 | int ret = 0; | |
254 | ||
0436e09f DB |
255 | if (f->hooks && f->hooks->before_ram_iterate) { |
256 | ret = f->hooks->before_ram_iterate(f, f->opaque, flags, NULL); | |
093c455a EH |
257 | if (ret < 0) { |
258 | qemu_file_set_error(f, ret); | |
259 | } | |
260 | } | |
261 | } | |
262 | ||
263 | void ram_control_after_iterate(QEMUFile *f, uint64_t flags) | |
264 | { | |
265 | int ret = 0; | |
266 | ||
0436e09f DB |
267 | if (f->hooks && f->hooks->after_ram_iterate) { |
268 | ret = f->hooks->after_ram_iterate(f, f->opaque, flags, NULL); | |
093c455a EH |
269 | if (ret < 0) { |
270 | qemu_file_set_error(f, ret); | |
271 | } | |
272 | } | |
273 | } | |
274 | ||
632e3a5c | 275 | void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data) |
093c455a EH |
276 | { |
277 | int ret = -EINVAL; | |
278 | ||
0436e09f DB |
279 | if (f->hooks && f->hooks->hook_ram_load) { |
280 | ret = f->hooks->hook_ram_load(f, f->opaque, flags, data); | |
093c455a EH |
281 | if (ret < 0) { |
282 | qemu_file_set_error(f, ret); | |
283 | } | |
284 | } else { | |
632e3a5c DDAG |
285 | /* |
286 | * Hook is a hook specifically requested by the source sending a flag | |
287 | * that expects there to be a hook on the destination. | |
288 | */ | |
289 | if (flags == RAM_CONTROL_HOOK) { | |
290 | qemu_file_set_error(f, ret); | |
291 | } | |
093c455a EH |
292 | } |
293 | } | |
294 | ||
295 | size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset, | |
6e1dea46 JQ |
296 | ram_addr_t offset, size_t size, |
297 | uint64_t *bytes_sent) | |
093c455a | 298 | { |
0436e09f DB |
299 | if (f->hooks && f->hooks->save_page) { |
300 | int ret = f->hooks->save_page(f, f->opaque, block_offset, | |
301 | offset, size, bytes_sent); | |
ccb7e1b5 LC |
302 | if (ret != RAM_SAVE_CONTROL_NOT_SUPP) { |
303 | f->bytes_xfer += size; | |
304 | } | |
305 | ||
306 | if (ret != RAM_SAVE_CONTROL_DELAYED && | |
307 | ret != RAM_SAVE_CONTROL_NOT_SUPP) { | |
093c455a EH |
308 | if (bytes_sent && *bytes_sent > 0) { |
309 | qemu_update_position(f, *bytes_sent); | |
310 | } else if (ret < 0) { | |
311 | qemu_file_set_error(f, ret); | |
312 | } | |
313 | } | |
314 | ||
315 | return ret; | |
316 | } | |
317 | ||
318 | return RAM_SAVE_CONTROL_NOT_SUPP; | |
319 | } | |
320 | ||
548f52ea DDAG |
321 | /* |
322 | * Attempt to fill the buffer from the underlying file | |
323 | * Returns the number of bytes read, or negative value for an error. | |
324 | * | |
325 | * Note that it can return a partially full buffer even in a not error/not EOF | |
326 | * case if the underlying file descriptor gives a short read, and that can | |
327 | * happen even on a blocking fd. | |
328 | */ | |
329 | static ssize_t qemu_fill_buffer(QEMUFile *f) | |
093c455a EH |
330 | { |
331 | int len; | |
332 | int pending; | |
3d661c8a | 333 | Error *local_error = NULL; |
093c455a EH |
334 | |
335 | assert(!qemu_file_is_writable(f)); | |
336 | ||
337 | pending = f->buf_size - f->buf_index; | |
338 | if (pending > 0) { | |
339 | memmove(f->buf, f->buf + f->buf_index, pending); | |
340 | } | |
341 | f->buf_index = 0; | |
342 | f->buf_size = pending; | |
343 | ||
a555b809 JQ |
344 | if (f->shutdown) { |
345 | return 0; | |
346 | } | |
347 | ||
093c455a | 348 | len = f->ops->get_buffer(f->opaque, f->buf + pending, f->pos, |
3d661c8a | 349 | IO_BUF_SIZE - pending, &local_error); |
093c455a EH |
350 | if (len > 0) { |
351 | f->buf_size += len; | |
352 | f->pos += len; | |
353 | } else if (len == 0) { | |
3d661c8a | 354 | qemu_file_set_error_obj(f, -EIO, local_error); |
093c455a | 355 | } else if (len != -EAGAIN) { |
3d661c8a YK |
356 | qemu_file_set_error_obj(f, len, local_error); |
357 | } else { | |
358 | error_free(local_error); | |
093c455a | 359 | } |
548f52ea DDAG |
360 | |
361 | return len; | |
093c455a EH |
362 | } |
363 | ||
093c455a EH |
364 | void qemu_update_position(QEMUFile *f, size_t size) |
365 | { | |
366 | f->pos += size; | |
367 | } | |
368 | ||
369 | /** Closes the file | |
370 | * | |
371 | * Returns negative error value if any error happened on previous operations or | |
372 | * while closing the file. Returns 0 or positive number on success. | |
373 | * | |
374 | * The meaning of return value on success depends on the specific backend | |
375 | * being used. | |
376 | */ | |
377 | int qemu_fclose(QEMUFile *f) | |
378 | { | |
379 | int ret; | |
380 | qemu_fflush(f); | |
381 | ret = qemu_file_get_error(f); | |
382 | ||
383 | if (f->ops->close) { | |
3d661c8a | 384 | int ret2 = f->ops->close(f->opaque, NULL); |
093c455a EH |
385 | if (ret >= 0) { |
386 | ret = ret2; | |
387 | } | |
388 | } | |
389 | /* If any error was spotted before closing, we should report it | |
390 | * instead of the close() return value. | |
391 | */ | |
392 | if (f->last_error) { | |
393 | ret = f->last_error; | |
394 | } | |
3d661c8a | 395 | error_free(f->last_error_obj); |
093c455a | 396 | g_free(f); |
9013dca5 | 397 | trace_qemu_file_fclose(); |
093c455a EH |
398 | return ret; |
399 | } | |
400 | ||
1bf57fb3 WY |
401 | /* |
402 | * Add buf to iovec. Do flush if iovec is full. | |
403 | * | |
404 | * Return values: | |
405 | * 1 iovec is full and flushed | |
406 | * 0 iovec is not flushed | |
407 | * | |
408 | */ | |
409 | static int add_to_iovec(QEMUFile *f, const uint8_t *buf, size_t size, | |
410 | bool may_free) | |
093c455a EH |
411 | { |
412 | /* check for adjacent buffer and coalesce them */ | |
413 | if (f->iovcnt > 0 && buf == f->iov[f->iovcnt - 1].iov_base + | |
53f09a10 PB |
414 | f->iov[f->iovcnt - 1].iov_len && |
415 | may_free == test_bit(f->iovcnt - 1, f->may_free)) | |
416 | { | |
093c455a EH |
417 | f->iov[f->iovcnt - 1].iov_len += size; |
418 | } else { | |
53f09a10 PB |
419 | if (may_free) { |
420 | set_bit(f->iovcnt, f->may_free); | |
421 | } | |
093c455a EH |
422 | f->iov[f->iovcnt].iov_base = (uint8_t *)buf; |
423 | f->iov[f->iovcnt++].iov_len = size; | |
424 | } | |
425 | ||
426 | if (f->iovcnt >= MAX_IOV_SIZE) { | |
427 | qemu_fflush(f); | |
1bf57fb3 WY |
428 | return 1; |
429 | } | |
430 | ||
431 | return 0; | |
432 | } | |
433 | ||
434 | static void add_buf_to_iovec(QEMUFile *f, size_t len) | |
435 | { | |
436 | if (!add_to_iovec(f, f->buf + f->buf_index, len, false)) { | |
437 | f->buf_index += len; | |
438 | if (f->buf_index == IO_BUF_SIZE) { | |
439 | qemu_fflush(f); | |
440 | } | |
093c455a EH |
441 | } |
442 | } | |
443 | ||
53f09a10 PB |
444 | void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, size_t size, |
445 | bool may_free) | |
093c455a | 446 | { |
093c455a EH |
447 | if (f->last_error) { |
448 | return; | |
449 | } | |
450 | ||
451 | f->bytes_xfer += size; | |
53f09a10 | 452 | add_to_iovec(f, buf, size, may_free); |
093c455a EH |
453 | } |
454 | ||
56f3835f | 455 | void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, size_t size) |
093c455a | 456 | { |
56f3835f | 457 | size_t l; |
093c455a EH |
458 | |
459 | if (f->last_error) { | |
460 | return; | |
461 | } | |
462 | ||
463 | while (size > 0) { | |
464 | l = IO_BUF_SIZE - f->buf_index; | |
465 | if (l > size) { | |
466 | l = size; | |
467 | } | |
468 | memcpy(f->buf + f->buf_index, buf, l); | |
469 | f->bytes_xfer += l; | |
1bf57fb3 | 470 | add_buf_to_iovec(f, l); |
093c455a EH |
471 | if (qemu_file_get_error(f)) { |
472 | break; | |
473 | } | |
474 | buf += l; | |
475 | size -= l; | |
476 | } | |
477 | } | |
478 | ||
479 | void qemu_put_byte(QEMUFile *f, int v) | |
480 | { | |
481 | if (f->last_error) { | |
482 | return; | |
483 | } | |
484 | ||
485 | f->buf[f->buf_index] = v; | |
486 | f->bytes_xfer++; | |
1bf57fb3 | 487 | add_buf_to_iovec(f, 1); |
093c455a EH |
488 | } |
489 | ||
490 | void qemu_file_skip(QEMUFile *f, int size) | |
491 | { | |
492 | if (f->buf_index + size <= f->buf_size) { | |
493 | f->buf_index += size; | |
494 | } | |
495 | } | |
496 | ||
548f52ea | 497 | /* |
7c1e52ba DDAG |
498 | * Read 'size' bytes from file (at 'offset') without moving the |
499 | * pointer and set 'buf' to point to that data. | |
548f52ea DDAG |
500 | * |
501 | * It will return size bytes unless there was an error, in which case it will | |
502 | * return as many as it managed to read (assuming blocking fd's which | |
503 | * all current QEMUFile are) | |
504 | */ | |
56f3835f | 505 | size_t qemu_peek_buffer(QEMUFile *f, uint8_t **buf, size_t size, size_t offset) |
093c455a | 506 | { |
56f3835f DDAG |
507 | ssize_t pending; |
508 | size_t index; | |
093c455a EH |
509 | |
510 | assert(!qemu_file_is_writable(f)); | |
548f52ea DDAG |
511 | assert(offset < IO_BUF_SIZE); |
512 | assert(size <= IO_BUF_SIZE - offset); | |
093c455a | 513 | |
548f52ea | 514 | /* The 1st byte to read from */ |
093c455a | 515 | index = f->buf_index + offset; |
548f52ea | 516 | /* The number of available bytes starting at index */ |
093c455a | 517 | pending = f->buf_size - index; |
548f52ea DDAG |
518 | |
519 | /* | |
520 | * qemu_fill_buffer might return just a few bytes, even when there isn't | |
521 | * an error, so loop collecting them until we get enough. | |
522 | */ | |
523 | while (pending < size) { | |
524 | int received = qemu_fill_buffer(f); | |
525 | ||
526 | if (received <= 0) { | |
527 | break; | |
528 | } | |
529 | ||
093c455a EH |
530 | index = f->buf_index + offset; |
531 | pending = f->buf_size - index; | |
532 | } | |
533 | ||
534 | if (pending <= 0) { | |
535 | return 0; | |
536 | } | |
537 | if (size > pending) { | |
538 | size = pending; | |
539 | } | |
540 | ||
7c1e52ba | 541 | *buf = f->buf + index; |
093c455a EH |
542 | return size; |
543 | } | |
544 | ||
548f52ea DDAG |
545 | /* |
546 | * Read 'size' bytes of data from the file into buf. | |
547 | * 'size' can be larger than the internal buffer. | |
548 | * | |
549 | * It will return size bytes unless there was an error, in which case it will | |
550 | * return as many as it managed to read (assuming blocking fd's which | |
551 | * all current QEMUFile are) | |
552 | */ | |
56f3835f | 553 | size_t qemu_get_buffer(QEMUFile *f, uint8_t *buf, size_t size) |
093c455a | 554 | { |
56f3835f DDAG |
555 | size_t pending = size; |
556 | size_t done = 0; | |
093c455a EH |
557 | |
558 | while (pending > 0) { | |
56f3835f | 559 | size_t res; |
7c1e52ba | 560 | uint8_t *src; |
093c455a | 561 | |
7c1e52ba | 562 | res = qemu_peek_buffer(f, &src, MIN(pending, IO_BUF_SIZE), 0); |
093c455a EH |
563 | if (res == 0) { |
564 | return done; | |
565 | } | |
7c1e52ba | 566 | memcpy(buf, src, res); |
093c455a EH |
567 | qemu_file_skip(f, res); |
568 | buf += res; | |
569 | pending -= res; | |
570 | done += res; | |
571 | } | |
572 | return done; | |
573 | } | |
574 | ||
9504fb51 DDAG |
575 | /* |
576 | * Read 'size' bytes of data from the file. | |
577 | * 'size' can be larger than the internal buffer. | |
578 | * | |
579 | * The data: | |
580 | * may be held on an internal buffer (in which case *buf is updated | |
581 | * to point to it) that is valid until the next qemu_file operation. | |
582 | * OR | |
583 | * will be copied to the *buf that was passed in. | |
584 | * | |
585 | * The code tries to avoid the copy if possible. | |
586 | * | |
587 | * It will return size bytes unless there was an error, in which case it will | |
588 | * return as many as it managed to read (assuming blocking fd's which | |
589 | * all current QEMUFile are) | |
590 | * | |
591 | * Note: Since **buf may get changed, the caller should take care to | |
592 | * keep a pointer to the original buffer if it needs to deallocate it. | |
593 | */ | |
594 | size_t qemu_get_buffer_in_place(QEMUFile *f, uint8_t **buf, size_t size) | |
595 | { | |
596 | if (size < IO_BUF_SIZE) { | |
597 | size_t res; | |
598 | uint8_t *src; | |
599 | ||
600 | res = qemu_peek_buffer(f, &src, size, 0); | |
601 | ||
602 | if (res == size) { | |
603 | qemu_file_skip(f, res); | |
604 | *buf = src; | |
605 | return res; | |
606 | } | |
607 | } | |
608 | ||
609 | return qemu_get_buffer(f, *buf, size); | |
610 | } | |
611 | ||
548f52ea DDAG |
612 | /* |
613 | * Peeks a single byte from the buffer; this isn't guaranteed to work if | |
614 | * offset leaves a gap after the previous read/peeked data. | |
615 | */ | |
093c455a EH |
616 | int qemu_peek_byte(QEMUFile *f, int offset) |
617 | { | |
618 | int index = f->buf_index + offset; | |
619 | ||
620 | assert(!qemu_file_is_writable(f)); | |
548f52ea | 621 | assert(offset < IO_BUF_SIZE); |
093c455a EH |
622 | |
623 | if (index >= f->buf_size) { | |
624 | qemu_fill_buffer(f); | |
625 | index = f->buf_index + offset; | |
626 | if (index >= f->buf_size) { | |
627 | return 0; | |
628 | } | |
629 | } | |
630 | return f->buf[index]; | |
631 | } | |
632 | ||
633 | int qemu_get_byte(QEMUFile *f) | |
634 | { | |
635 | int result; | |
636 | ||
637 | result = qemu_peek_byte(f, 0); | |
638 | qemu_file_skip(f, 1); | |
639 | return result; | |
640 | } | |
641 | ||
97221400 AG |
642 | int64_t qemu_ftell_fast(QEMUFile *f) |
643 | { | |
644 | int64_t ret = f->pos; | |
645 | int i; | |
646 | ||
11808bb0 DB |
647 | for (i = 0; i < f->iovcnt; i++) { |
648 | ret += f->iov[i].iov_len; | |
97221400 AG |
649 | } |
650 | ||
651 | return ret; | |
652 | } | |
653 | ||
093c455a EH |
654 | int64_t qemu_ftell(QEMUFile *f) |
655 | { | |
656 | qemu_fflush(f); | |
657 | return f->pos; | |
658 | } | |
659 | ||
660 | int qemu_file_rate_limit(QEMUFile *f) | |
661 | { | |
a555b809 JQ |
662 | if (f->shutdown) { |
663 | return 1; | |
664 | } | |
093c455a EH |
665 | if (qemu_file_get_error(f)) { |
666 | return 1; | |
667 | } | |
668 | if (f->xfer_limit > 0 && f->bytes_xfer > f->xfer_limit) { | |
669 | return 1; | |
670 | } | |
671 | return 0; | |
672 | } | |
673 | ||
674 | int64_t qemu_file_get_rate_limit(QEMUFile *f) | |
675 | { | |
676 | return f->xfer_limit; | |
677 | } | |
678 | ||
679 | void qemu_file_set_rate_limit(QEMUFile *f, int64_t limit) | |
680 | { | |
681 | f->xfer_limit = limit; | |
682 | } | |
683 | ||
684 | void qemu_file_reset_rate_limit(QEMUFile *f) | |
685 | { | |
686 | f->bytes_xfer = 0; | |
687 | } | |
688 | ||
5d7d2558 IR |
689 | void qemu_file_update_transfer(QEMUFile *f, int64_t len) |
690 | { | |
691 | f->bytes_xfer += len; | |
692 | } | |
693 | ||
093c455a EH |
694 | void qemu_put_be16(QEMUFile *f, unsigned int v) |
695 | { | |
696 | qemu_put_byte(f, v >> 8); | |
697 | qemu_put_byte(f, v); | |
698 | } | |
699 | ||
700 | void qemu_put_be32(QEMUFile *f, unsigned int v) | |
701 | { | |
702 | qemu_put_byte(f, v >> 24); | |
703 | qemu_put_byte(f, v >> 16); | |
704 | qemu_put_byte(f, v >> 8); | |
705 | qemu_put_byte(f, v); | |
706 | } | |
707 | ||
708 | void qemu_put_be64(QEMUFile *f, uint64_t v) | |
709 | { | |
710 | qemu_put_be32(f, v >> 32); | |
711 | qemu_put_be32(f, v); | |
712 | } | |
713 | ||
714 | unsigned int qemu_get_be16(QEMUFile *f) | |
715 | { | |
716 | unsigned int v; | |
717 | v = qemu_get_byte(f) << 8; | |
718 | v |= qemu_get_byte(f); | |
719 | return v; | |
720 | } | |
721 | ||
722 | unsigned int qemu_get_be32(QEMUFile *f) | |
723 | { | |
724 | unsigned int v; | |
90d6a673 | 725 | v = (unsigned int)qemu_get_byte(f) << 24; |
093c455a EH |
726 | v |= qemu_get_byte(f) << 16; |
727 | v |= qemu_get_byte(f) << 8; | |
728 | v |= qemu_get_byte(f); | |
729 | return v; | |
730 | } | |
731 | ||
732 | uint64_t qemu_get_be64(QEMUFile *f) | |
733 | { | |
734 | uint64_t v; | |
735 | v = (uint64_t)qemu_get_be32(f) << 32; | |
736 | v |= qemu_get_be32(f); | |
737 | return v; | |
738 | } | |
44f0eadc | 739 | |
dcaf446e XG |
740 | /* return the size after compression, or negative value on error */ |
741 | static int qemu_compress_data(z_stream *stream, uint8_t *dest, size_t dest_len, | |
742 | const uint8_t *source, size_t source_len) | |
743 | { | |
744 | int err; | |
745 | ||
746 | err = deflateReset(stream); | |
747 | if (err != Z_OK) { | |
748 | return -1; | |
749 | } | |
750 | ||
751 | stream->avail_in = source_len; | |
752 | stream->next_in = (uint8_t *)source; | |
753 | stream->avail_out = dest_len; | |
754 | stream->next_out = dest; | |
755 | ||
756 | err = deflate(stream, Z_FINISH); | |
757 | if (err != Z_STREAM_END) { | |
758 | return -1; | |
759 | } | |
760 | ||
761 | return stream->next_out - dest; | |
762 | } | |
763 | ||
764 | /* Compress size bytes of data start at p and store the compressed | |
765 | * data to the buffer of f. | |
b3be2896 | 766 | * |
42d24611 WY |
767 | * Since the file is dummy file with empty_ops, return -1 if f has no space to |
768 | * save the compressed data. | |
44f0eadc | 769 | */ |
dcaf446e XG |
770 | ssize_t qemu_put_compression_data(QEMUFile *f, z_stream *stream, |
771 | const uint8_t *p, size_t size) | |
44f0eadc LL |
772 | { |
773 | ssize_t blen = IO_BUF_SIZE - f->buf_index - sizeof(int32_t); | |
774 | ||
775 | if (blen < compressBound(size)) { | |
42d24611 | 776 | return -1; |
44f0eadc | 777 | } |
dcaf446e XG |
778 | |
779 | blen = qemu_compress_data(stream, f->buf + f->buf_index + sizeof(int32_t), | |
780 | blen, p, size); | |
781 | if (blen < 0) { | |
34ab9e97 | 782 | return -1; |
44f0eadc | 783 | } |
34ab9e97 | 784 | |
44f0eadc | 785 | qemu_put_be32(f, blen); |
1bf57fb3 | 786 | add_buf_to_iovec(f, blen); |
44f0eadc LL |
787 | return blen + sizeof(int32_t); |
788 | } | |
789 | ||
790 | /* Put the data in the buffer of f_src to the buffer of f_des, and | |
791 | * then reset the buf_index of f_src to 0. | |
792 | */ | |
793 | ||
794 | int qemu_put_qemu_file(QEMUFile *f_des, QEMUFile *f_src) | |
795 | { | |
796 | int len = 0; | |
797 | ||
798 | if (f_src->buf_index > 0) { | |
799 | len = f_src->buf_index; | |
800 | qemu_put_buffer(f_des, f_src->buf, f_src->buf_index); | |
801 | f_src->buf_index = 0; | |
787d134f | 802 | f_src->iovcnt = 0; |
44f0eadc LL |
803 | } |
804 | return len; | |
805 | } | |
b3af1bc9 DDAG |
806 | |
807 | /* | |
808 | * Get a string whose length is determined by a single preceding byte | |
809 | * A preallocated 256 byte buffer must be passed in. | |
810 | * Returns: len on success and a 0 terminated string in the buffer | |
811 | * else 0 | |
812 | * (Note a 0 length string will return 0 either way) | |
813 | */ | |
814 | size_t qemu_get_counted_string(QEMUFile *f, char buf[256]) | |
815 | { | |
816 | size_t len = qemu_get_byte(f); | |
817 | size_t res = qemu_get_buffer(f, (uint8_t *)buf, len); | |
818 | ||
819 | buf[res] = 0; | |
820 | ||
821 | return res == len ? res : 0; | |
822 | } | |
a800cd5c | 823 | |
f0d64cb7 VSO |
824 | /* |
825 | * Put a string with one preceding byte containing its length. The length of | |
826 | * the string should be less than 256. | |
827 | */ | |
828 | void qemu_put_counted_string(QEMUFile *f, const char *str) | |
829 | { | |
830 | size_t len = strlen(str); | |
831 | ||
832 | assert(len < 256); | |
833 | qemu_put_byte(f, len); | |
834 | qemu_put_buffer(f, (const uint8_t *)str, len); | |
835 | } | |
836 | ||
a800cd5c DDAG |
837 | /* |
838 | * Set the blocking state of the QEMUFile. | |
839 | * Note: On some transports the OS only keeps a single blocking state for | |
840 | * both directions, and thus changing the blocking on the main | |
841 | * QEMUFile can also affect the return path. | |
842 | */ | |
843 | void qemu_file_set_blocking(QEMUFile *f, bool block) | |
844 | { | |
06ad5135 | 845 | if (f->ops->set_blocking) { |
3d661c8a | 846 | f->ops->set_blocking(f->opaque, block, NULL); |
a800cd5c DDAG |
847 | } |
848 | } |