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-common.h"
25 #include "qemu/host-utils.h"
30 #include "qemu/sockets.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
;
150 return 32 - clz32(i
);
154 * Make sure data goes on disk, but if possible do not bother to
155 * write out the inode just for timestamp updates.
157 * Unfortunately even in 2009 many operating systems do not support
158 * fdatasync and have to fall back to fsync.
160 int qemu_fdatasync(int fd
)
162 #ifdef CONFIG_FDATASYNC
163 return fdatasync(fd
);
170 * Searches for an area with non-zero content in a buffer
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.
177 * can_use_buffer_find_nonzero_offset() can be used to check
178 * these requirements.
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)
186 * If the buffer is all zero the return value is equal to len.
189 size_t buffer_find_nonzero_offset(const void *buf
, size_t len
)
191 const VECTYPE
*p
= buf
;
192 const VECTYPE zero
= (VECTYPE
){0};
195 assert(can_use_buffer_find_nonzero_offset(buf
, len
));
201 for (i
= 0; i
< BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR
; i
++) {
202 if (!ALL_EQ(p
[i
], zero
)) {
203 return i
* sizeof(VECTYPE
);
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
= VEC_OR(p
[i
+ 0], p
[i
+ 1]);
211 VECTYPE tmp1
= VEC_OR(p
[i
+ 2], p
[i
+ 3]);
212 VECTYPE tmp2
= VEC_OR(p
[i
+ 4], p
[i
+ 5]);
213 VECTYPE tmp3
= VEC_OR(p
[i
+ 6], p
[i
+ 7]);
214 VECTYPE tmp01
= VEC_OR(tmp0
, tmp1
);
215 VECTYPE tmp23
= VEC_OR(tmp2
, tmp3
);
216 if (!ALL_EQ(VEC_OR(tmp01
, tmp23
), zero
)) {
221 return i
* sizeof(VECTYPE
);
225 * Checks if a buffer is all zeroes
227 * Attention! The len must be a multiple of 4 * sizeof(long) due to
228 * restriction of optimizations in this function.
230 bool buffer_is_zero(const void *buf
, size_t len
)
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
240 const long * const data
= buf
;
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
;
247 assert(len
% (4 * sizeof(long)) == 0);
250 for (i
= 0; i
< len
; i
+= 4) {
256 if (d0
|| d1
|| d2
|| d3
) {
265 /* Sets a specific flag */
266 int fcntl_setfl(int fd
, int flag
)
270 flags
= fcntl(fd
, F_GETFL
);
274 if (fcntl(fd
, F_SETFL
, flags
| flag
) == -1)
281 static int64_t suffix_mul(char suffix
, int64_t unit
)
283 switch (qemu_toupper(suffix
)) {
284 case STRTOSZ_DEFSUFFIX_B
:
286 case STRTOSZ_DEFSUFFIX_KB
:
288 case STRTOSZ_DEFSUFFIX_MB
:
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
;
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
308 int64_t strtosz_suffix_unit(const char *nptr
, char **end
,
309 const char default_suffix
, int64_t unit
)
311 int64_t retval
= -EINVAL
;
314 int mul_required
= 0;
315 double val
, mul
, integral
, fraction
;
318 val
= strtod(nptr
, &endptr
);
319 if (isnan(val
) || endptr
== nptr
|| errno
!= 0) {
322 fraction
= modf(val
, &integral
);
327 mul
= suffix_mul(c
, unit
);
331 mul
= suffix_mul(default_suffix
, unit
);
334 if (mul
== 1 && mul_required
) {
337 if ((val
* mul
>= INT64_MAX
) || val
< 0) {
351 int64_t strtosz_suffix(const char *nptr
, char **end
, const char default_suffix
)
353 return strtosz_suffix_unit(nptr
, end
, default_suffix
, 1024);
356 int64_t strtosz(const char *nptr
, char **end
)
358 return strtosz_suffix(nptr
, end
, STRTOSZ_DEFSUFFIX_MB
);
362 * Helper function for qemu_strto*l() functions.
364 static int check_strtox_error(const char **next
, char *endptr
,
367 if (!next
&& *endptr
) {
377 * QEMU wrappers for strtol(), strtoll(), strtoul(), strotull() C functions.
379 * Convert ASCII string @nptr to a long integer value
380 * from the given @base. Parameters @nptr, @endptr, @base
381 * follows same semantics as strtol() C function.
383 * Unlike from strtol() function, if @endptr is not NULL, this
384 * function will return -EINVAL whenever it cannot fully convert
385 * the string in @nptr with given @base to a long. This function returns
386 * the result of the conversion only through the @result parameter.
388 * If NULL is passed in @endptr, then the whole string in @ntpr
389 * is a number otherwise it returns -EINVAL.
392 * Unlike from strtol() function, this wrapper returns either
393 * -EINVAL or the errno set by strtol() function (e.g -ERANGE).
394 * If the conversion overflows, -ERANGE is returned, and @result
395 * is set to the max value of the desired type
396 * (e.g. LONG_MAX, LLONG_MAX, ULONG_MAX, ULLONG_MAX). If the case
397 * of underflow, -ERANGE is returned, and @result is set to the min
398 * value of the desired type. For strtol(), strtoll(), @result is set to
399 * LONG_MIN, LLONG_MIN, respectively, and for strtoul(), strtoull() it
402 int qemu_strtol(const char *nptr
, const char **endptr
, int base
,
414 *result
= strtol(nptr
, &p
, base
);
415 err
= check_strtox_error(endptr
, p
, errno
);
421 * Converts ASCII string to an unsigned long integer.
423 * If string contains a negative number, value will be converted to
424 * the unsigned representation of the signed value, unless the original
425 * (nonnegated) value would overflow, in this case, it will set @result
426 * to ULONG_MAX, and return ERANGE.
428 * The same behavior holds, for qemu_strtoull() but sets @result to
429 * ULLONG_MAX instead of ULONG_MAX.
431 * See qemu_strtol() documentation for more info.
433 int qemu_strtoul(const char *nptr
, const char **endptr
, int base
,
434 unsigned long *result
)
445 *result
= strtoul(nptr
, &p
, base
);
446 err
= check_strtox_error(endptr
, p
, errno
);
452 * Converts ASCII string to a long long integer.
454 * See qemu_strtol() documentation for more info.
456 int qemu_strtoll(const char *nptr
, const char **endptr
, int base
,
468 *result
= strtoll(nptr
, &p
, base
);
469 err
= check_strtox_error(endptr
, p
, errno
);
477 * @s: String to parse
478 * @value: Destination for parsed integer value
479 * @endptr: Destination for pointer to first character not consumed
480 * @base: integer base, between 2 and 36 inclusive, or 0
482 * Parse unsigned integer
484 * Parsed syntax is like strtoull()'s: arbitrary whitespace, a single optional
485 * '+' or '-', an optional "0x" if @base is 0 or 16, one or more digits.
487 * If @s is null, or @base is invalid, or @s doesn't start with an
488 * integer in the syntax above, set *@value to 0, *@endptr to @s, and
491 * Set *@endptr to point right beyond the parsed integer (even if the integer
492 * overflows or is negative, all digits will be parsed and *@endptr will
493 * point right beyond them).
495 * If the integer is negative, set *@value to 0, and return -ERANGE.
497 * If the integer overflows unsigned long long, set *@value to
498 * ULLONG_MAX, and return -ERANGE.
500 * Else, set *@value to the parsed integer, and return 0.
502 int parse_uint(const char *s
, unsigned long long *value
, char **endptr
,
506 char *endp
= (char *)s
;
507 unsigned long long val
= 0;
515 val
= strtoull(s
, &endp
, base
);
526 /* make sure we reject negative numbers: */
527 while (isspace((unsigned char)*s
)) {
545 * @s: String to parse
546 * @value: Destination for parsed integer value
547 * @base: integer base, between 2 and 36 inclusive, or 0
549 * Parse unsigned integer from entire string
551 * Have the same behavior of parse_uint(), but with an additional check
552 * for additional data after the parsed number. If extra characters are present
553 * after the parsed number, the function will return -EINVAL, and *@v will
556 int parse_uint_full(const char *s
, unsigned long long *value
, int base
)
561 r
= parse_uint(s
, value
, &endp
, base
);
573 int qemu_parse_fd(const char *param
)
579 fd
= strtol(param
, &endptr
, 10);
580 if (param
== endptr
/* no conversion performed */ ||
581 errno
!= 0 /* not representable as long; possibly others */ ||
582 *endptr
!= '\0' /* final string not empty */ ||
583 fd
< 0 /* invalid as file descriptor */ ||
584 fd
> INT_MAX
/* not representable as int */) {
590 /* round down to the nearest power of 2*/
591 int64_t pow2floor(int64_t value
)
593 if (!is_power_of_2(value
)) {
594 value
= 0x8000000000000000ULL
>> clz64(value
);
599 /* round up to the nearest power of 2 (0 if overflow) */
600 uint64_t pow2ceil(uint64_t value
)
602 uint8_t nlz
= clz64(value
);
604 if (is_power_of_2(value
)) {
610 return 1ULL << (64 - nlz
);
614 * Implementation of ULEB128 (http://en.wikipedia.org/wiki/LEB128)
615 * Input is limited to 14-bit numbers
617 int uleb128_encode_small(uint8_t *out
, uint32_t n
)
619 g_assert(n
<= 0x3fff);
624 *out
++ = (n
& 0x7f) | 0x80;
630 int uleb128_decode_small(const uint8_t *in
, uint32_t *n
)
637 /* we exceed 14 bit number */
647 * helper to parse debug environment variables
649 int parse_debug_env(const char *name
, int max
, int initial
)
651 char *debug_env
= getenv(name
);
659 debug
= strtol(debug_env
, &inv
, 10);
660 if (inv
== debug_env
) {
663 if (debug
< 0 || debug
> max
|| errno
!= 0) {
664 fprintf(stderr
, "warning: %s not in [0, %d]", name
, max
);
671 * Helper to print ethernet mac address
673 const char *qemu_ether_ntoa(const MACAddr
*mac
)
677 snprintf(ret
, sizeof(ret
), "%02x:%02x:%02x:%02x:%02x:%02x",
678 mac
->a
[0], mac
->a
[1], mac
->a
[2], mac
->a
[3], mac
->a
[4], mac
->a
[5]);