mips: Ensure PC update with MTC0 single-stepping
[qemu.git] / util / cutils.c
1 /*
2 * Simple C functions to supplement the C library
3 *
4 * Copyright (c) 2006 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 */
24 #include "qemu-common.h"
25 #include "qemu/host-utils.h"
26 #include <math.h>
27 #include <limits.h>
28 #include <errno.h>
29
30 #include "qemu/sockets.h"
31 #include "qemu/iov.h"
32 #include "net/net.h"
33
34 void strpadcpy(char *buf, int buf_size, const char *str, char pad)
35 {
36 int len = qemu_strnlen(str, buf_size);
37 memcpy(buf, str, len);
38 memset(buf + len, pad, buf_size - len);
39 }
40
41 void pstrcpy(char *buf, int buf_size, const char *str)
42 {
43 int c;
44 char *q = buf;
45
46 if (buf_size <= 0)
47 return;
48
49 for(;;) {
50 c = *str++;
51 if (c == 0 || q >= buf + buf_size - 1)
52 break;
53 *q++ = c;
54 }
55 *q = '\0';
56 }
57
58 /* strcat and truncate. */
59 char *pstrcat(char *buf, int buf_size, const char *s)
60 {
61 int len;
62 len = strlen(buf);
63 if (len < buf_size)
64 pstrcpy(buf + len, buf_size - len, s);
65 return buf;
66 }
67
68 int strstart(const char *str, const char *val, const char **ptr)
69 {
70 const char *p, *q;
71 p = str;
72 q = val;
73 while (*q != '\0') {
74 if (*p != *q)
75 return 0;
76 p++;
77 q++;
78 }
79 if (ptr)
80 *ptr = p;
81 return 1;
82 }
83
84 int stristart(const char *str, const char *val, const char **ptr)
85 {
86 const char *p, *q;
87 p = str;
88 q = val;
89 while (*q != '\0') {
90 if (qemu_toupper(*p) != qemu_toupper(*q))
91 return 0;
92 p++;
93 q++;
94 }
95 if (ptr)
96 *ptr = p;
97 return 1;
98 }
99
100 /* XXX: use host strnlen if available ? */
101 int qemu_strnlen(const char *s, int max_len)
102 {
103 int i;
104
105 for(i = 0; i < max_len; i++) {
106 if (s[i] == '\0') {
107 break;
108 }
109 }
110 return i;
111 }
112
113 char *qemu_strsep(char **input, const char *delim)
114 {
115 char *result = *input;
116 if (result != NULL) {
117 char *p;
118
119 for (p = result; *p != '\0'; p++) {
120 if (strchr(delim, *p)) {
121 break;
122 }
123 }
124 if (*p == '\0') {
125 *input = NULL;
126 } else {
127 *p = '\0';
128 *input = p + 1;
129 }
130 }
131 return result;
132 }
133
134 time_t mktimegm(struct tm *tm)
135 {
136 time_t t;
137 int y = tm->tm_year + 1900, m = tm->tm_mon + 1, d = tm->tm_mday;
138 if (m < 3) {
139 m += 12;
140 y--;
141 }
142 t = 86400ULL * (d + (153 * m - 457) / 5 + 365 * y + y / 4 - y / 100 +
143 y / 400 - 719469);
144 t += 3600 * tm->tm_hour + 60 * tm->tm_min + tm->tm_sec;
145 return t;
146 }
147
148 int qemu_fls(int i)
149 {
150 return 32 - clz32(i);
151 }
152
153 /*
154 * Make sure data goes on disk, but if possible do not bother to
155 * write out the inode just for timestamp updates.
156 *
157 * Unfortunately even in 2009 many operating systems do not support
158 * fdatasync and have to fall back to fsync.
159 */
160 int qemu_fdatasync(int fd)
161 {
162 #ifdef CONFIG_FDATASYNC
163 return fdatasync(fd);
164 #else
165 return fsync(fd);
166 #endif
167 }
168
169 /*
170 * Searches for an area with non-zero content in a buffer
171 *
172 * Attention! The len must be a multiple of
173 * BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR * sizeof(VECTYPE)
174 * and addr must be a multiple of sizeof(VECTYPE) due to
175 * restriction of optimizations in this function.
176 *
177 * can_use_buffer_find_nonzero_offset() can be used to check
178 * these requirements.
179 *
180 * The return value is the offset of the non-zero area rounded
181 * down to a multiple of sizeof(VECTYPE) for the first
182 * BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR chunks and down to
183 * BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR * sizeof(VECTYPE)
184 * afterwards.
185 *
186 * If the buffer is all zero the return value is equal to len.
187 */
188
189 size_t buffer_find_nonzero_offset(const void *buf, size_t len)
190 {
191 const VECTYPE *p = buf;
192 const VECTYPE zero = (VECTYPE){0};
193 size_t i;
194
195 assert(can_use_buffer_find_nonzero_offset(buf, len));
196
197 if (!len) {
198 return 0;
199 }
200
201 for (i = 0; i < BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR; i++) {
202 if (!ALL_EQ(p[i], zero)) {
203 return i * sizeof(VECTYPE);
204 }
205 }
206
207 for (i = BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR;
208 i < len / sizeof(VECTYPE);
209 i += BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR) {
210 VECTYPE tmp0 = p[i + 0] | p[i + 1];
211 VECTYPE tmp1 = p[i + 2] | p[i + 3];
212 VECTYPE tmp2 = p[i + 4] | p[i + 5];
213 VECTYPE tmp3 = p[i + 6] | p[i + 7];
214 VECTYPE tmp01 = tmp0 | tmp1;
215 VECTYPE tmp23 = tmp2 | tmp3;
216 if (!ALL_EQ(tmp01 | tmp23, zero)) {
217 break;
218 }
219 }
220
221 return i * sizeof(VECTYPE);
222 }
223
224 /*
225 * Checks if a buffer is all zeroes
226 *
227 * Attention! The len must be a multiple of 4 * sizeof(long) due to
228 * restriction of optimizations in this function.
229 */
230 bool buffer_is_zero(const void *buf, size_t len)
231 {
232 /*
233 * Use long as the biggest available internal data type that fits into the
234 * CPU register and unroll the loop to smooth out the effect of memory
235 * latency.
236 */
237
238 size_t i;
239 long d0, d1, d2, d3;
240 const long * const data = buf;
241
242 /* use vector optimized zero check if possible */
243 if (can_use_buffer_find_nonzero_offset(buf, len)) {
244 return buffer_find_nonzero_offset(buf, len) == len;
245 }
246
247 assert(len % (4 * sizeof(long)) == 0);
248 len /= sizeof(long);
249
250 for (i = 0; i < len; i += 4) {
251 d0 = data[i + 0];
252 d1 = data[i + 1];
253 d2 = data[i + 2];
254 d3 = data[i + 3];
255
256 if (d0 || d1 || d2 || d3) {
257 return false;
258 }
259 }
260
261 return true;
262 }
263
264 #ifndef _WIN32
265 /* Sets a specific flag */
266 int fcntl_setfl(int fd, int flag)
267 {
268 int flags;
269
270 flags = fcntl(fd, F_GETFL);
271 if (flags == -1)
272 return -errno;
273
274 if (fcntl(fd, F_SETFL, flags | flag) == -1)
275 return -errno;
276
277 return 0;
278 }
279 #endif
280
281 static int64_t suffix_mul(char suffix, int64_t unit)
282 {
283 switch (qemu_toupper(suffix)) {
284 case STRTOSZ_DEFSUFFIX_B:
285 return 1;
286 case STRTOSZ_DEFSUFFIX_KB:
287 return unit;
288 case STRTOSZ_DEFSUFFIX_MB:
289 return unit * unit;
290 case STRTOSZ_DEFSUFFIX_GB:
291 return unit * unit * unit;
292 case STRTOSZ_DEFSUFFIX_TB:
293 return unit * unit * unit * unit;
294 case STRTOSZ_DEFSUFFIX_PB:
295 return unit * unit * unit * unit * unit;
296 case STRTOSZ_DEFSUFFIX_EB:
297 return unit * unit * unit * unit * unit * unit;
298 }
299 return -1;
300 }
301
302 /*
303 * Convert string to bytes, allowing either B/b for bytes, K/k for KB,
304 * M/m for MB, G/g for GB or T/t for TB. End pointer will be returned
305 * in *end, if not NULL. Return -ERANGE on overflow, Return -EINVAL on
306 * other error.
307 */
308 int64_t strtosz_suffix_unit(const char *nptr, char **end,
309 const char default_suffix, int64_t unit)
310 {
311 int64_t retval = -EINVAL;
312 char *endptr;
313 unsigned char c;
314 int mul_required = 0;
315 double val, mul, integral, fraction;
316
317 errno = 0;
318 val = strtod(nptr, &endptr);
319 if (isnan(val) || endptr == nptr || errno != 0) {
320 goto fail;
321 }
322 fraction = modf(val, &integral);
323 if (fraction != 0) {
324 mul_required = 1;
325 }
326 c = *endptr;
327 mul = suffix_mul(c, unit);
328 if (mul >= 0) {
329 endptr++;
330 } else {
331 mul = suffix_mul(default_suffix, unit);
332 assert(mul >= 0);
333 }
334 if (mul == 1 && mul_required) {
335 goto fail;
336 }
337 if ((val * mul >= INT64_MAX) || val < 0) {
338 retval = -ERANGE;
339 goto fail;
340 }
341 retval = val * mul;
342
343 fail:
344 if (end) {
345 *end = endptr;
346 }
347
348 return retval;
349 }
350
351 int64_t strtosz_suffix(const char *nptr, char **end, const char default_suffix)
352 {
353 return strtosz_suffix_unit(nptr, end, default_suffix, 1024);
354 }
355
356 int64_t strtosz(const char *nptr, char **end)
357 {
358 return strtosz_suffix(nptr, end, STRTOSZ_DEFSUFFIX_MB);
359 }
360
361 /**
362 * parse_uint:
363 *
364 * @s: String to parse
365 * @value: Destination for parsed integer value
366 * @endptr: Destination for pointer to first character not consumed
367 * @base: integer base, between 2 and 36 inclusive, or 0
368 *
369 * Parse unsigned integer
370 *
371 * Parsed syntax is like strtoull()'s: arbitrary whitespace, a single optional
372 * '+' or '-', an optional "0x" if @base is 0 or 16, one or more digits.
373 *
374 * If @s is null, or @base is invalid, or @s doesn't start with an
375 * integer in the syntax above, set *@value to 0, *@endptr to @s, and
376 * return -EINVAL.
377 *
378 * Set *@endptr to point right beyond the parsed integer (even if the integer
379 * overflows or is negative, all digits will be parsed and *@endptr will
380 * point right beyond them).
381 *
382 * If the integer is negative, set *@value to 0, and return -ERANGE.
383 *
384 * If the integer overflows unsigned long long, set *@value to
385 * ULLONG_MAX, and return -ERANGE.
386 *
387 * Else, set *@value to the parsed integer, and return 0.
388 */
389 int parse_uint(const char *s, unsigned long long *value, char **endptr,
390 int base)
391 {
392 int r = 0;
393 char *endp = (char *)s;
394 unsigned long long val = 0;
395
396 if (!s) {
397 r = -EINVAL;
398 goto out;
399 }
400
401 errno = 0;
402 val = strtoull(s, &endp, base);
403 if (errno) {
404 r = -errno;
405 goto out;
406 }
407
408 if (endp == s) {
409 r = -EINVAL;
410 goto out;
411 }
412
413 /* make sure we reject negative numbers: */
414 while (isspace((unsigned char)*s)) {
415 s++;
416 }
417 if (*s == '-') {
418 val = 0;
419 r = -ERANGE;
420 goto out;
421 }
422
423 out:
424 *value = val;
425 *endptr = endp;
426 return r;
427 }
428
429 /**
430 * parse_uint_full:
431 *
432 * @s: String to parse
433 * @value: Destination for parsed integer value
434 * @base: integer base, between 2 and 36 inclusive, or 0
435 *
436 * Parse unsigned integer from entire string
437 *
438 * Have the same behavior of parse_uint(), but with an additional check
439 * for additional data after the parsed number. If extra characters are present
440 * after the parsed number, the function will return -EINVAL, and *@v will
441 * be set to 0.
442 */
443 int parse_uint_full(const char *s, unsigned long long *value, int base)
444 {
445 char *endp;
446 int r;
447
448 r = parse_uint(s, value, &endp, base);
449 if (r < 0) {
450 return r;
451 }
452 if (*endp) {
453 *value = 0;
454 return -EINVAL;
455 }
456
457 return 0;
458 }
459
460 int qemu_parse_fd(const char *param)
461 {
462 long fd;
463 char *endptr;
464
465 errno = 0;
466 fd = strtol(param, &endptr, 10);
467 if (param == endptr /* no conversion performed */ ||
468 errno != 0 /* not representable as long; possibly others */ ||
469 *endptr != '\0' /* final string not empty */ ||
470 fd < 0 /* invalid as file descriptor */ ||
471 fd > INT_MAX /* not representable as int */) {
472 return -1;
473 }
474 return fd;
475 }
476
477 /* round down to the nearest power of 2*/
478 int64_t pow2floor(int64_t value)
479 {
480 if (!is_power_of_2(value)) {
481 value = 0x8000000000000000ULL >> clz64(value);
482 }
483 return value;
484 }
485
486 /*
487 * Implementation of ULEB128 (http://en.wikipedia.org/wiki/LEB128)
488 * Input is limited to 14-bit numbers
489 */
490 int uleb128_encode_small(uint8_t *out, uint32_t n)
491 {
492 g_assert(n <= 0x3fff);
493 if (n < 0x80) {
494 *out++ = n;
495 return 1;
496 } else {
497 *out++ = (n & 0x7f) | 0x80;
498 *out++ = n >> 7;
499 return 2;
500 }
501 }
502
503 int uleb128_decode_small(const uint8_t *in, uint32_t *n)
504 {
505 if (!(*in & 0x80)) {
506 *n = *in++;
507 return 1;
508 } else {
509 *n = *in++ & 0x7f;
510 /* we exceed 14 bit number */
511 if (*in & 0x80) {
512 return -1;
513 }
514 *n |= *in++ << 7;
515 return 2;
516 }
517 }
518
519 /*
520 * helper to parse debug environment variables
521 */
522 int parse_debug_env(const char *name, int max, int initial)
523 {
524 char *debug_env = getenv(name);
525 char *inv = NULL;
526 int debug;
527
528 if (!debug_env) {
529 return initial;
530 }
531 debug = strtol(debug_env, &inv, 10);
532 if (inv == debug_env) {
533 return initial;
534 }
535 if (debug < 0 || debug > max) {
536 fprintf(stderr, "warning: %s not in [0, %d]", name, max);
537 return initial;
538 }
539 return debug;
540 }
541
542 /*
543 * Helper to print ethernet mac address
544 */
545 const char *qemu_ether_ntoa(const MACAddr *mac)
546 {
547 static char ret[18];
548
549 snprintf(ret, sizeof(ret), "%02x:%02x:%02x:%02x:%02x:%02x",
550 mac->a[0], mac->a[1], mac->a[2], mac->a[3], mac->a[4], mac->a[5]);
551
552 return ret;
553 }