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git.proxmox.com Git - mirror_ovs.git/blob - lib/util.h
2 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 Nicira, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
20 #include <arpa/inet.h>
29 #include "openvswitch/util.h"
31 extern char *program_name
;
33 #define __ARRAY_SIZE_NOCHECK(ARRAY) (sizeof(ARRAY) / sizeof((ARRAY)[0]))
35 /* return 0 for array types, 1 otherwise */
36 #define __ARRAY_CHECK(ARRAY) \
37 !__builtin_types_compatible_p(typeof(ARRAY), typeof(&ARRAY[0]))
39 /* compile-time fail if not array */
40 #define __ARRAY_FAIL(ARRAY) (sizeof(char[-2*!__ARRAY_CHECK(ARRAY)]))
41 #define __ARRAY_SIZE(ARRAY) \
42 __builtin_choose_expr(__ARRAY_CHECK(ARRAY), \
43 __ARRAY_SIZE_NOCHECK(ARRAY), __ARRAY_FAIL(ARRAY))
45 #define __ARRAY_SIZE(ARRAY) __ARRAY_SIZE_NOCHECK(ARRAY)
49 /* This system's cache line size, in bytes.
50 * Being wrong hurts performance but not correctness. */
51 #define CACHE_LINE_SIZE 64
52 BUILD_ASSERT_DECL(IS_POW2(CACHE_LINE_SIZE
));
55 ovs_prefetch_range(const void *start
, size_t size
)
57 const char *addr
= (const char *)start
;
60 for (ofs
= 0; ofs
< size
; ofs
+= CACHE_LINE_SIZE
) {
61 OVS_PREFETCH(addr
+ ofs
);
66 #define MIN(X, Y) ((X) < (Y) ? (X) : (Y))
70 #define MAX(X, Y) ((X) > (Y) ? (X) : (Y))
73 /* Comparisons for ints with modular arithmetic */
74 #define INT_MOD_LT(a,b) ((int) ((a)-(b)) < 0)
75 #define INT_MOD_LEQ(a,b) ((int) ((a)-(b)) <= 0)
76 #define INT_MOD_GT(a,b) ((int) ((a)-(b)) > 0)
77 #define INT_MOD_GEQ(a,b) ((int) ((a)-(b)) >= 0)
79 #define INT_MOD_MIN(a, b) ((INT_MOD_LT(a, b)) ? (a) : (b))
80 #define INT_MOD_MAX(a, b) ((INT_MOD_GT(a, b)) ? (a) : (b))
82 #define OVS_NOT_REACHED() abort()
84 /* Use "%"PRIuSIZE to format size_t with printf(). */
102 typedef uint32_t HANDLE
;
109 #define set_program_name(name) \
110 ovs_set_program_name(name, OVS_PACKAGE_VERSION)
112 const char *get_subprogram_name(void);
113 void set_subprogram_name(const char *);
115 void ovs_print_version(uint8_t min_ofp
, uint8_t max_ofp
);
117 OVS_NO_RETURN
void out_of_memory(void);
118 void *xmalloc(size_t) MALLOC_LIKE
;
119 void *xcalloc(size_t, size_t) MALLOC_LIKE
;
120 void *xzalloc(size_t) MALLOC_LIKE
;
121 void *xrealloc(void *, size_t);
122 void *xmemdup(const void *, size_t) MALLOC_LIKE
;
123 char *xmemdup0(const char *, size_t) MALLOC_LIKE
;
124 char *xstrdup(const char *) MALLOC_LIKE
;
125 char *nullable_xstrdup(const char *) MALLOC_LIKE
;
126 bool nullable_string_is_equal(const char *a
, const char *b
);
127 char *xasprintf(const char *format
, ...) OVS_PRINTF_FORMAT(1, 2) MALLOC_LIKE
;
128 char *xvasprintf(const char *format
, va_list) OVS_PRINTF_FORMAT(1, 0) MALLOC_LIKE
;
129 void *x2nrealloc(void *p
, size_t *n
, size_t s
);
131 void *xmalloc_cacheline(size_t) MALLOC_LIKE
;
132 void *xzalloc_cacheline(size_t) MALLOC_LIKE
;
133 void free_cacheline(void *);
135 void ovs_strlcpy(char *dst
, const char *src
, size_t size
);
136 void ovs_strzcpy(char *dst
, const char *src
, size_t size
);
138 OVS_NO_RETURN
void ovs_abort(int err_no
, const char *format
, ...)
139 OVS_PRINTF_FORMAT(2, 3);
140 OVS_NO_RETURN
void ovs_abort_valist(int err_no
, const char *format
, va_list)
141 OVS_PRINTF_FORMAT(2, 0);
142 OVS_NO_RETURN
void ovs_fatal(int err_no
, const char *format
, ...)
143 OVS_PRINTF_FORMAT(2, 3);
144 OVS_NO_RETURN
void ovs_fatal_valist(int err_no
, const char *format
, va_list)
145 OVS_PRINTF_FORMAT(2, 0);
146 void ovs_error(int err_no
, const char *format
, ...) OVS_PRINTF_FORMAT(2, 3);
147 void ovs_error_valist(int err_no
, const char *format
, va_list)
148 OVS_PRINTF_FORMAT(2, 0);
149 const char *ovs_retval_to_string(int);
150 const char *ovs_strerror(int);
151 void ovs_hex_dump(FILE *, const void *, size_t, uintptr_t offset
, bool ascii
);
153 bool str_to_int(const char *, int base
, int *);
154 bool str_to_long(const char *, int base
, long *);
155 bool str_to_llong(const char *, int base
, long long *);
156 bool str_to_llong_with_tail(const char *, char **, int base
, long long *);
157 bool str_to_uint(const char *, int base
, unsigned int *);
158 bool str_to_llong_range(const char *, int base
, long long *, long long *);
160 bool ovs_scan(const char *s
, const char *format
, ...) OVS_SCANF_FORMAT(2, 3);
161 bool ovs_scan_len(const char *s
, int *n
, const char *format
, ...);
163 bool str_to_double(const char *, double *);
165 int hexit_value(int c
);
166 uintmax_t hexits_value(const char *s
, size_t n
, bool *ok
);
168 int parse_int_string(const char *s
, uint8_t *valuep
, int field_width
,
171 const char *english_list_delimiter(size_t index
, size_t total
);
175 char *dir_name(const char *file_name
);
176 char *base_name(const char *file_name
);
178 char *abs_file_name(const char *dir
, const char *file_name
);
180 char *follow_symlinks(const char *filename
);
182 void ignore(bool x OVS_UNUSED
);
186 /* Returns the number of trailing 0-bits in 'n'. Undefined if 'n' == 0. */
191 /* With GCC 4.7 on 32-bit x86, if a 32-bit integer is passed as 'n', using
192 * a plain __builtin_ctzll() here always generates an out-of-line function
193 * call. The test below helps it to emit a single 'bsf' instruction. */
194 return (__builtin_constant_p(n
<= UINT32_MAX
) && n
<= UINT32_MAX
196 : __builtin_ctzll(n
));
200 raw_clz64(uint64_t n
)
202 return __builtin_clzll(n
);
210 _BitScanForward64(&r
, n
);
213 unsigned long low
= n
, high
, r
= 0;
214 if (_BitScanForward(&r
, low
)) {
218 _BitScanForward(&r
, high
);
224 raw_clz64(uint64_t n
)
228 _BitScanReverse64(&r
, n
);
231 unsigned long low
, high
= n
>> 32, r
= 0;
232 if (_BitScanReverse(&r
, high
)) {
236 _BitScanReverse(&r
, low
);
241 /* Defined in util.c. */
242 int raw_ctz(uint64_t n
);
243 int raw_clz64(uint64_t n
);
246 /* Returns the number of trailing 0-bits in 'n', or 32 if 'n' is 0. */
250 return n
? raw_ctz(n
) : 32;
253 /* Returns the number of trailing 0-bits in 'n', or 64 if 'n' is 0. */
257 return n
? raw_ctz(n
) : 64;
260 /* Returns the number of leading 0-bits in 'n', or 32 if 'n' is 0. */
264 return n
? raw_clz64(n
) - 32 : 32;
267 /* Returns the number of leading 0-bits in 'n', or 64 if 'n' is 0. */
271 return n
? raw_clz64(n
) : 64;
274 /* Given a word 'n', calculates floor(log_2('n')). This is equivalent
275 * to finding the bit position of the most significant one bit in 'n'. It is
276 * an error to call this function with 'n' == 0. */
278 log_2_floor(uint64_t n
)
280 return 63 - raw_clz64(n
);
283 /* Given a word 'n', calculates ceil(log_2('n')). It is an error to
284 * call this function with 'n' == 0. */
286 log_2_ceil(uint64_t n
)
288 return log_2_floor(n
) + !is_pow2(n
);
291 /* unsigned int count_1bits(uint64_t x):
293 * Returns the number of 1-bits in 'x', between 0 and 64 inclusive. */
294 #if UINTPTR_MAX == UINT64_MAX
295 static inline unsigned int
296 count_1bits(uint64_t x
)
298 #if __GNUC__ >= 4 && __POPCNT__
299 return __builtin_popcountll(x
);
301 /* This portable implementation is the fastest one we know of for 64
302 * bits, and about 3x faster than GCC 4.7 __builtin_popcountll(). */
303 const uint64_t h55
= UINT64_C(0x5555555555555555);
304 const uint64_t h33
= UINT64_C(0x3333333333333333);
305 const uint64_t h0F
= UINT64_C(0x0F0F0F0F0F0F0F0F);
306 const uint64_t h01
= UINT64_C(0x0101010101010101);
307 x
-= (x
>> 1) & h55
; /* Count of each 2 bits in-place. */
308 x
= (x
& h33
) + ((x
>> 2) & h33
); /* Count of each 4 bits in-place. */
309 x
= (x
+ (x
>> 4)) & h0F
; /* Count of each 8 bits in-place. */
310 return (x
* h01
) >> 56; /* Sum of all bytes. */
313 #else /* Not 64-bit. */
314 #if __GNUC__ >= 4 && __POPCNT__
315 static inline unsigned int
316 count_1bits_32__(uint32_t x
)
318 return __builtin_popcount(x
);
321 #define NEED_COUNT_1BITS_8 1
322 extern const uint8_t count_1bits_8
[256];
323 static inline unsigned int
324 count_1bits_32__(uint32_t x
)
326 /* This portable implementation is the fastest one we know of for 32 bits,
327 * and faster than GCC __builtin_popcount(). */
328 return (count_1bits_8
[x
& 0xff] +
329 count_1bits_8
[(x
>> 8) & 0xff] +
330 count_1bits_8
[(x
>> 16) & 0xff] +
331 count_1bits_8
[x
>> 24]);
334 static inline unsigned int
335 count_1bits(uint64_t x
)
337 return count_1bits_32__(x
) + count_1bits_32__(x
>> 32);
341 /* Returns the rightmost 1-bit in 'x' (e.g. 01011000 => 00001000), or 0 if 'x'
343 static inline uintmax_t
344 rightmost_1bit(uintmax_t x
)
349 /* Returns 'x' with its rightmost 1-bit changed to a zero (e.g. 01011000 =>
350 * 01010000), or 0 if 'x' is 0. */
351 static inline uintmax_t
352 zero_rightmost_1bit(uintmax_t x
)
357 /* Returns the index of the rightmost 1-bit in 'x' (e.g. 01011000 => 3), or an
358 * undefined value if 'x' is 0. */
360 rightmost_1bit_idx(uint64_t x
)
365 /* Returns the index of the leftmost 1-bit in 'x' (e.g. 01011000 => 6), or an
366 * undefined value if 'x' is 0. */
367 static inline uint32_t
368 leftmost_1bit_idx(uint64_t x
)
370 return log_2_floor(x
);
373 /* Return a ovs_be32 prefix in network byte order with 'plen' highest bits set.
374 * Shift with 32 is undefined behavior, but we rather use 64-bit shift than
376 static inline ovs_be32
be32_prefix_mask(int plen
)
378 return htonl((uint64_t)UINT32_MAX
<< (32 - plen
));
381 bool is_all_zeros(const void *, size_t);
382 bool is_all_ones(const void *, size_t);
383 void bitwise_copy(const void *src
, unsigned int src_len
, unsigned int src_ofs
,
384 void *dst
, unsigned int dst_len
, unsigned int dst_ofs
,
385 unsigned int n_bits
);
386 void bitwise_zero(void *dst_
, unsigned int dst_len
, unsigned dst_ofs
,
387 unsigned int n_bits
);
388 void bitwise_one(void *dst_
, unsigned int dst_len
, unsigned dst_ofs
,
389 unsigned int n_bits
);
390 bool bitwise_is_all_zeros(const void *, unsigned int len
, unsigned int ofs
,
391 unsigned int n_bits
);
392 unsigned int bitwise_scan(const void *, unsigned int len
,
393 bool target
, unsigned int start
, unsigned int end
);
394 int bitwise_rscan(const void *, unsigned int len
, bool target
,
396 void bitwise_put(uint64_t value
,
397 void *dst
, unsigned int dst_len
, unsigned int dst_ofs
,
398 unsigned int n_bits
);
399 uint64_t bitwise_get(const void *src
, unsigned int src_len
,
400 unsigned int src_ofs
, unsigned int n_bits
);
401 bool bitwise_get_bit(const void *src
, unsigned int len
, unsigned int ofs
);
402 void bitwise_put0(void *dst
, unsigned int len
, unsigned int ofs
);
403 void bitwise_put1(void *dst
, unsigned int len
, unsigned int ofs
);
404 void bitwise_put_bit(void *dst
, unsigned int len
, unsigned int ofs
, bool);
405 void bitwise_toggle_bit(void *dst
, unsigned int len
, unsigned int ofs
);
407 /* Returns non-zero if the parameters have equal value. */
409 ovs_u128_equals(const ovs_u128 a
, const ovs_u128 b
)
411 return (a
.u64
.hi
== b
.u64
.hi
) && (a
.u64
.lo
== b
.u64
.lo
);
414 /* Returns true if 'val' is 0. */
416 ovs_u128_is_zero(const ovs_u128 val
)
418 return !(val
.u64
.hi
|| val
.u64
.lo
);
421 /* Returns true if 'val' is all ones. */
423 ovs_u128_is_ones(const ovs_u128 val
)
425 return ovs_u128_equals(val
, OVS_U128_MAX
);
428 /* Returns non-zero if the parameters have equal value. */
430 ovs_be128_equals(const ovs_be128 a
, const ovs_be128 b
)
432 return (a
.be64
.hi
== b
.be64
.hi
) && (a
.be64
.lo
== b
.be64
.lo
);
435 /* Returns true if 'val' is 0. */
437 ovs_be128_is_zero(const ovs_be128 val
)
439 return !(val
.be64
.hi
|| val
.be64
.lo
);
442 static inline ovs_u128
443 ovs_u128_and(const ovs_u128 a
, const ovs_u128 b
)
447 dst
.u64
.hi
= a
.u64
.hi
& b
.u64
.hi
;
448 dst
.u64
.lo
= a
.u64
.lo
& b
.u64
.lo
;
453 void xsleep(unsigned int seconds
);
455 bool is_stdout_a_tty(void);
459 char *ovs_format_message(int error
);
460 char *ovs_lasterror_to_string(void);
461 int ftruncate(int fd
, off_t length
);