2 * Simple C functions to supplement the C library
4 * Copyright (c) 2006 Fabrice Bellard
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:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
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
24 #include "qemu/osdep.h"
25 #include "qemu-common.h"
26 #include "qemu/host-utils.h"
29 #include "qemu/sockets.h"
32 #include "qemu/cutils.h"
34 void strpadcpy(char *buf
, int buf_size
, const char *str
, char pad
)
36 int len
= qemu_strnlen(str
, buf_size
);
37 memcpy(buf
, str
, len
);
38 memset(buf
+ len
, pad
, buf_size
- len
);
41 void pstrcpy(char *buf
, int buf_size
, const char *str
)
51 if (c
== 0 || q
>= buf
+ buf_size
- 1)
58 /* strcat and truncate. */
59 char *pstrcat(char *buf
, int buf_size
, const char *s
)
64 pstrcpy(buf
+ len
, buf_size
- len
, s
);
68 int strstart(const char *str
, const char *val
, const char **ptr
)
84 int stristart(const char *str
, const char *val
, const char **ptr
)
90 if (qemu_toupper(*p
) != qemu_toupper(*q
))
100 /* XXX: use host strnlen if available ? */
101 int qemu_strnlen(const char *s
, int max_len
)
105 for(i
= 0; i
< max_len
; i
++) {
113 char *qemu_strsep(char **input
, const char *delim
)
115 char *result
= *input
;
116 if (result
!= NULL
) {
119 for (p
= result
; *p
!= '\0'; p
++) {
120 if (strchr(delim
, *p
)) {
134 time_t mktimegm(struct tm
*tm
)
137 int y
= tm
->tm_year
+ 1900, m
= tm
->tm_mon
+ 1, d
= tm
->tm_mday
;
142 t
= 86400ULL * (d
+ (153 * m
- 457) / 5 + 365 * y
+ y
/ 4 - y
/ 100 +
144 t
+= 3600 * tm
->tm_hour
+ 60 * tm
->tm_min
+ tm
->tm_sec
;
149 * Make sure data goes on disk, but if possible do not bother to
150 * write out the inode just for timestamp updates.
152 * Unfortunately even in 2009 many operating systems do not support
153 * fdatasync and have to fall back to fsync.
155 int qemu_fdatasync(int fd
)
157 #ifdef CONFIG_FDATASYNC
158 return fdatasync(fd
);
164 /* vector definitions */
167 /* The altivec.h header says we're allowed to undef these for
168 * C++ compatibility. Here we don't care about C++, but we
169 * undef them anyway to avoid namespace pollution.
174 #define VECTYPE __vector unsigned char
175 #define SPLAT(p) vec_splat(vec_ld(0, p), 0)
176 #define ALL_EQ(v1, v2) vec_all_eq(v1, v2)
177 #define VEC_OR(v1, v2) ((v1) | (v2))
178 /* altivec.h may redefine the bool macro as vector type.
179 * Reset it to POSIX semantics. */
181 #elif defined __SSE2__
182 #include <emmintrin.h>
183 #define VECTYPE __m128i
184 #define SPLAT(p) _mm_set1_epi8(*(p))
185 #define ALL_EQ(v1, v2) (_mm_movemask_epi8(_mm_cmpeq_epi8(v1, v2)) == 0xFFFF)
186 #define VEC_OR(v1, v2) (_mm_or_si128(v1, v2))
188 #define VECTYPE unsigned long
189 #define SPLAT(p) (*(p) * (~0UL / 255))
190 #define ALL_EQ(v1, v2) ((v1) == (v2))
191 #define VEC_OR(v1, v2) ((v1) | (v2))
194 #define BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR 8
197 can_use_buffer_find_nonzero_offset_inner(const void *buf
, size_t len
)
199 return (len
% (BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR
200 * sizeof(VECTYPE
)) == 0
201 && ((uintptr_t) buf
) % sizeof(VECTYPE
) == 0);
205 * Searches for an area with non-zero content in a buffer
207 * Attention! The len must be a multiple of
208 * BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR * sizeof(VECTYPE)
209 * and addr must be a multiple of sizeof(VECTYPE) due to
210 * restriction of optimizations in this function.
212 * can_use_buffer_find_nonzero_offset_inner() can be used to
213 * check these requirements.
215 * The return value is the offset of the non-zero area rounded
216 * down to a multiple of sizeof(VECTYPE) for the first
217 * BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR chunks and down to
218 * BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR * sizeof(VECTYPE)
221 * If the buffer is all zero the return value is equal to len.
224 static size_t buffer_find_nonzero_offset_inner(const void *buf
, size_t len
)
226 const VECTYPE
*p
= buf
;
227 const VECTYPE zero
= (VECTYPE
){0};
230 assert(can_use_buffer_find_nonzero_offset_inner(buf
, len
));
236 for (i
= 0; i
< BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR
; i
++) {
237 if (!ALL_EQ(p
[i
], zero
)) {
238 return i
* sizeof(VECTYPE
);
242 for (i
= BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR
;
243 i
< len
/ sizeof(VECTYPE
);
244 i
+= BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR
) {
245 VECTYPE tmp0
= VEC_OR(p
[i
+ 0], p
[i
+ 1]);
246 VECTYPE tmp1
= VEC_OR(p
[i
+ 2], p
[i
+ 3]);
247 VECTYPE tmp2
= VEC_OR(p
[i
+ 4], p
[i
+ 5]);
248 VECTYPE tmp3
= VEC_OR(p
[i
+ 6], p
[i
+ 7]);
249 VECTYPE tmp01
= VEC_OR(tmp0
, tmp1
);
250 VECTYPE tmp23
= VEC_OR(tmp2
, tmp3
);
251 if (!ALL_EQ(VEC_OR(tmp01
, tmp23
), zero
)) {
256 return i
* sizeof(VECTYPE
);
259 #if defined CONFIG_AVX2_OPT
260 #pragma GCC push_options
261 #pragma GCC target("avx2")
263 #include <immintrin.h>
265 #define AVX2_VECTYPE __m256i
266 #define AVX2_SPLAT(p) _mm256_set1_epi8(*(p))
267 #define AVX2_ALL_EQ(v1, v2) \
268 (_mm256_movemask_epi8(_mm256_cmpeq_epi8(v1, v2)) == 0xFFFFFFFF)
269 #define AVX2_VEC_OR(v1, v2) (_mm256_or_si256(v1, v2))
272 can_use_buffer_find_nonzero_offset_avx2(const void *buf
, size_t len
)
274 return (len
% (BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR
275 * sizeof(AVX2_VECTYPE
)) == 0
276 && ((uintptr_t) buf
) % sizeof(AVX2_VECTYPE
) == 0);
279 static size_t buffer_find_nonzero_offset_avx2(const void *buf
, size_t len
)
281 const AVX2_VECTYPE
*p
= buf
;
282 const AVX2_VECTYPE zero
= (AVX2_VECTYPE
){0};
285 assert(can_use_buffer_find_nonzero_offset_avx2(buf
, len
));
291 for (i
= 0; i
< BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR
; i
++) {
292 if (!AVX2_ALL_EQ(p
[i
], zero
)) {
293 return i
* sizeof(AVX2_VECTYPE
);
297 for (i
= BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR
;
298 i
< len
/ sizeof(AVX2_VECTYPE
);
299 i
+= BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR
) {
300 AVX2_VECTYPE tmp0
= AVX2_VEC_OR(p
[i
+ 0], p
[i
+ 1]);
301 AVX2_VECTYPE tmp1
= AVX2_VEC_OR(p
[i
+ 2], p
[i
+ 3]);
302 AVX2_VECTYPE tmp2
= AVX2_VEC_OR(p
[i
+ 4], p
[i
+ 5]);
303 AVX2_VECTYPE tmp3
= AVX2_VEC_OR(p
[i
+ 6], p
[i
+ 7]);
304 AVX2_VECTYPE tmp01
= AVX2_VEC_OR(tmp0
, tmp1
);
305 AVX2_VECTYPE tmp23
= AVX2_VEC_OR(tmp2
, tmp3
);
306 if (!AVX2_ALL_EQ(AVX2_VEC_OR(tmp01
, tmp23
), zero
)) {
311 return i
* sizeof(AVX2_VECTYPE
);
314 static bool avx2_support(void)
318 if (__get_cpuid_max(0, NULL
) < 7) {
322 __cpuid_count(7, 0, a
, b
, c
, d
);
327 bool can_use_buffer_find_nonzero_offset(const void *buf
, size_t len
) \
328 __attribute__ ((ifunc("can_use_buffer_find_nonzero_offset_ifunc")));
329 size_t buffer_find_nonzero_offset(const void *buf
, size_t len
) \
330 __attribute__ ((ifunc("buffer_find_nonzero_offset_ifunc")));
332 static void *buffer_find_nonzero_offset_ifunc(void)
334 typeof(buffer_find_nonzero_offset
) *func
= (avx2_support()) ?
335 buffer_find_nonzero_offset_avx2
: buffer_find_nonzero_offset_inner
;
340 static void *can_use_buffer_find_nonzero_offset_ifunc(void)
342 typeof(can_use_buffer_find_nonzero_offset
) *func
= (avx2_support()) ?
343 can_use_buffer_find_nonzero_offset_avx2
:
344 can_use_buffer_find_nonzero_offset_inner
;
348 #pragma GCC pop_options
350 bool can_use_buffer_find_nonzero_offset(const void *buf
, size_t len
)
352 return can_use_buffer_find_nonzero_offset_inner(buf
, len
);
355 size_t buffer_find_nonzero_offset(const void *buf
, size_t len
)
357 return buffer_find_nonzero_offset_inner(buf
, len
);
362 * Checks if a buffer is all zeroes
364 * Attention! The len must be a multiple of 4 * sizeof(long) due to
365 * restriction of optimizations in this function.
367 bool buffer_is_zero(const void *buf
, size_t len
)
370 * Use long as the biggest available internal data type that fits into the
371 * CPU register and unroll the loop to smooth out the effect of memory
377 const long * const data
= buf
;
379 /* use vector optimized zero check if possible */
380 if (can_use_buffer_find_nonzero_offset(buf
, len
)) {
381 return buffer_find_nonzero_offset(buf
, len
) == len
;
384 assert(len
% (4 * sizeof(long)) == 0);
387 for (i
= 0; i
< len
; i
+= 4) {
393 if (d0
|| d1
|| d2
|| d3
) {
402 /* Sets a specific flag */
403 int fcntl_setfl(int fd
, int flag
)
407 flags
= fcntl(fd
, F_GETFL
);
411 if (fcntl(fd
, F_SETFL
, flags
| flag
) == -1)
418 static int64_t suffix_mul(char suffix
, int64_t unit
)
420 switch (qemu_toupper(suffix
)) {
421 case QEMU_STRTOSZ_DEFSUFFIX_B
:
423 case QEMU_STRTOSZ_DEFSUFFIX_KB
:
425 case QEMU_STRTOSZ_DEFSUFFIX_MB
:
427 case QEMU_STRTOSZ_DEFSUFFIX_GB
:
428 return unit
* unit
* unit
;
429 case QEMU_STRTOSZ_DEFSUFFIX_TB
:
430 return unit
* unit
* unit
* unit
;
431 case QEMU_STRTOSZ_DEFSUFFIX_PB
:
432 return unit
* unit
* unit
* unit
* unit
;
433 case QEMU_STRTOSZ_DEFSUFFIX_EB
:
434 return unit
* unit
* unit
* unit
* unit
* unit
;
440 * Convert string to bytes, allowing either B/b for bytes, K/k for KB,
441 * M/m for MB, G/g for GB or T/t for TB. End pointer will be returned
442 * in *end, if not NULL. Return -ERANGE on overflow, Return -EINVAL on
445 int64_t qemu_strtosz_suffix_unit(const char *nptr
, char **end
,
446 const char default_suffix
, int64_t unit
)
448 int64_t retval
= -EINVAL
;
451 int mul_required
= 0;
452 double val
, mul
, integral
, fraction
;
455 val
= strtod(nptr
, &endptr
);
456 if (isnan(val
) || endptr
== nptr
|| errno
!= 0) {
459 fraction
= modf(val
, &integral
);
464 mul
= suffix_mul(c
, unit
);
468 mul
= suffix_mul(default_suffix
, unit
);
471 if (mul
== 1 && mul_required
) {
474 if ((val
* mul
>= INT64_MAX
) || val
< 0) {
488 int64_t qemu_strtosz_suffix(const char *nptr
, char **end
,
489 const char default_suffix
)
491 return qemu_strtosz_suffix_unit(nptr
, end
, default_suffix
, 1024);
494 int64_t qemu_strtosz(const char *nptr
, char **end
)
496 return qemu_strtosz_suffix(nptr
, end
, QEMU_STRTOSZ_DEFSUFFIX_MB
);
500 * Helper function for qemu_strto*l() functions.
502 static int check_strtox_error(const char *p
, char *endptr
, const char **next
,
505 /* If no conversion was performed, prefer BSD behavior over glibc
508 if (err
== 0 && endptr
== p
) {
511 if (!next
&& *endptr
) {
521 * QEMU wrappers for strtol(), strtoll(), strtoul(), strotull() C functions.
523 * Convert ASCII string @nptr to a long integer value
524 * from the given @base. Parameters @nptr, @endptr, @base
525 * follows same semantics as strtol() C function.
527 * Unlike from strtol() function, if @endptr is not NULL, this
528 * function will return -EINVAL whenever it cannot fully convert
529 * the string in @nptr with given @base to a long. This function returns
530 * the result of the conversion only through the @result parameter.
532 * If NULL is passed in @endptr, then the whole string in @ntpr
533 * is a number otherwise it returns -EINVAL.
536 * Unlike from strtol() function, this wrapper returns either
537 * -EINVAL or the errno set by strtol() function (e.g -ERANGE).
538 * If the conversion overflows, -ERANGE is returned, and @result
539 * is set to the max value of the desired type
540 * (e.g. LONG_MAX, LLONG_MAX, ULONG_MAX, ULLONG_MAX). If the case
541 * of underflow, -ERANGE is returned, and @result is set to the min
542 * value of the desired type. For strtol(), strtoll(), @result is set to
543 * LONG_MIN, LLONG_MIN, respectively, and for strtoul(), strtoull() it
546 int qemu_strtol(const char *nptr
, const char **endptr
, int base
,
558 *result
= strtol(nptr
, &p
, base
);
559 err
= check_strtox_error(nptr
, p
, endptr
, errno
);
565 * Converts ASCII string to an unsigned long integer.
567 * If string contains a negative number, value will be converted to
568 * the unsigned representation of the signed value, unless the original
569 * (nonnegated) value would overflow, in this case, it will set @result
570 * to ULONG_MAX, and return ERANGE.
572 * The same behavior holds, for qemu_strtoull() but sets @result to
573 * ULLONG_MAX instead of ULONG_MAX.
575 * See qemu_strtol() documentation for more info.
577 int qemu_strtoul(const char *nptr
, const char **endptr
, int base
,
578 unsigned long *result
)
589 *result
= strtoul(nptr
, &p
, base
);
590 /* Windows returns 1 for negative out-of-range values. */
591 if (errno
== ERANGE
) {
594 err
= check_strtox_error(nptr
, p
, endptr
, errno
);
600 * Converts ASCII string to a long long integer.
602 * See qemu_strtol() documentation for more info.
604 int qemu_strtoll(const char *nptr
, const char **endptr
, int base
,
616 *result
= strtoll(nptr
, &p
, base
);
617 err
= check_strtox_error(nptr
, p
, endptr
, errno
);
623 * Converts ASCII string to an unsigned long long integer.
625 * See qemu_strtol() documentation for more info.
627 int qemu_strtoull(const char *nptr
, const char **endptr
, int base
,
639 *result
= strtoull(nptr
, &p
, base
);
640 /* Windows returns 1 for negative out-of-range values. */
641 if (errno
== ERANGE
) {
644 err
= check_strtox_error(nptr
, p
, endptr
, errno
);
652 * @s: String to parse
653 * @value: Destination for parsed integer value
654 * @endptr: Destination for pointer to first character not consumed
655 * @base: integer base, between 2 and 36 inclusive, or 0
657 * Parse unsigned integer
659 * Parsed syntax is like strtoull()'s: arbitrary whitespace, a single optional
660 * '+' or '-', an optional "0x" if @base is 0 or 16, one or more digits.
662 * If @s is null, or @base is invalid, or @s doesn't start with an
663 * integer in the syntax above, set *@value to 0, *@endptr to @s, and
666 * Set *@endptr to point right beyond the parsed integer (even if the integer
667 * overflows or is negative, all digits will be parsed and *@endptr will
668 * point right beyond them).
670 * If the integer is negative, set *@value to 0, and return -ERANGE.
672 * If the integer overflows unsigned long long, set *@value to
673 * ULLONG_MAX, and return -ERANGE.
675 * Else, set *@value to the parsed integer, and return 0.
677 int parse_uint(const char *s
, unsigned long long *value
, char **endptr
,
681 char *endp
= (char *)s
;
682 unsigned long long val
= 0;
690 val
= strtoull(s
, &endp
, base
);
701 /* make sure we reject negative numbers: */
702 while (isspace((unsigned char)*s
)) {
720 * @s: String to parse
721 * @value: Destination for parsed integer value
722 * @base: integer base, between 2 and 36 inclusive, or 0
724 * Parse unsigned integer from entire string
726 * Have the same behavior of parse_uint(), but with an additional check
727 * for additional data after the parsed number. If extra characters are present
728 * after the parsed number, the function will return -EINVAL, and *@v will
731 int parse_uint_full(const char *s
, unsigned long long *value
, int base
)
736 r
= parse_uint(s
, value
, &endp
, base
);
748 int qemu_parse_fd(const char *param
)
754 fd
= strtol(param
, &endptr
, 10);
755 if (param
== endptr
/* no conversion performed */ ||
756 errno
!= 0 /* not representable as long; possibly others */ ||
757 *endptr
!= '\0' /* final string not empty */ ||
758 fd
< 0 /* invalid as file descriptor */ ||
759 fd
> INT_MAX
/* not representable as int */) {
766 * Implementation of ULEB128 (http://en.wikipedia.org/wiki/LEB128)
767 * Input is limited to 14-bit numbers
769 int uleb128_encode_small(uint8_t *out
, uint32_t n
)
771 g_assert(n
<= 0x3fff);
776 *out
++ = (n
& 0x7f) | 0x80;
782 int uleb128_decode_small(const uint8_t *in
, uint32_t *n
)
789 /* we exceed 14 bit number */
799 * helper to parse debug environment variables
801 int parse_debug_env(const char *name
, int max
, int initial
)
803 char *debug_env
= getenv(name
);
811 debug
= strtol(debug_env
, &inv
, 10);
812 if (inv
== debug_env
) {
815 if (debug
< 0 || debug
> max
|| errno
!= 0) {
816 fprintf(stderr
, "warning: %s not in [0, %d]", name
, max
);
823 * Helper to print ethernet mac address
825 const char *qemu_ether_ntoa(const MACAddr
*mac
)
829 snprintf(ret
, sizeof(ret
), "%02x:%02x:%02x:%02x:%02x:%02x",
830 mac
->a
[0], mac
->a
[1], mac
->a
[2], mac
->a
[3], mac
->a
[4], mac
->a
[5]);