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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>
28 #include "openvswitch/util.h"
30 extern char *program_name
;
32 #define __ARRAY_SIZE_NOCHECK(ARRAY) (sizeof(ARRAY) / sizeof((ARRAY)[0]))
34 /* return 0 for array types, 1 otherwise */
35 #define __ARRAY_CHECK(ARRAY) \
36 !__builtin_types_compatible_p(typeof(ARRAY), typeof(&ARRAY[0]))
38 /* compile-time fail if not array */
39 #define __ARRAY_FAIL(ARRAY) (sizeof(char[-2*!__ARRAY_CHECK(ARRAY)]))
40 #define __ARRAY_SIZE(ARRAY) \
41 __builtin_choose_expr(__ARRAY_CHECK(ARRAY), \
42 __ARRAY_SIZE_NOCHECK(ARRAY), __ARRAY_FAIL(ARRAY))
44 #define __ARRAY_SIZE(ARRAY) __ARRAY_SIZE_NOCHECK(ARRAY)
48 /* This system's cache line size, in bytes.
49 * Being wrong hurts performance but not correctness. */
50 #define CACHE_LINE_SIZE 64
51 BUILD_ASSERT_DECL(IS_POW2(CACHE_LINE_SIZE
));
54 ovs_prefetch_range(const void *start
, size_t size
)
56 const char *addr
= (const char *)start
;
59 for (ofs
= 0; ofs
< size
; ofs
+= CACHE_LINE_SIZE
) {
60 OVS_PREFETCH(addr
+ ofs
);
65 #define MIN(X, Y) ((X) < (Y) ? (X) : (Y))
69 #define MAX(X, Y) ((X) > (Y) ? (X) : (Y))
72 #define OVS_NOT_REACHED() abort()
74 /* Use "%"PRIuSIZE to format size_t with printf(). */
92 typedef uint32_t HANDLE
;
99 #define set_program_name(name) \
100 ovs_set_program_name(name, OVS_PACKAGE_VERSION)
102 const char *get_subprogram_name(void);
103 void set_subprogram_name(const char *);
105 void ovs_print_version(uint8_t min_ofp
, uint8_t max_ofp
);
107 OVS_NO_RETURN
void out_of_memory(void);
108 void *xmalloc(size_t) MALLOC_LIKE
;
109 void *xcalloc(size_t, size_t) MALLOC_LIKE
;
110 void *xzalloc(size_t) MALLOC_LIKE
;
111 void *xrealloc(void *, size_t);
112 void *xmemdup(const void *, size_t) MALLOC_LIKE
;
113 char *xmemdup0(const char *, size_t) MALLOC_LIKE
;
114 char *xstrdup(const char *) MALLOC_LIKE
;
115 char *nullable_xstrdup(const char *) MALLOC_LIKE
;
116 char *xasprintf(const char *format
, ...) OVS_PRINTF_FORMAT(1, 2) MALLOC_LIKE
;
117 char *xvasprintf(const char *format
, va_list) OVS_PRINTF_FORMAT(1, 0) MALLOC_LIKE
;
118 void *x2nrealloc(void *p
, size_t *n
, size_t s
);
120 void *xmalloc_cacheline(size_t) MALLOC_LIKE
;
121 void *xzalloc_cacheline(size_t) MALLOC_LIKE
;
122 void free_cacheline(void *);
124 void ovs_strlcpy(char *dst
, const char *src
, size_t size
);
125 void ovs_strzcpy(char *dst
, const char *src
, size_t size
);
127 OVS_NO_RETURN
void ovs_abort(int err_no
, const char *format
, ...)
128 OVS_PRINTF_FORMAT(2, 3);
129 OVS_NO_RETURN
void ovs_abort_valist(int err_no
, const char *format
, va_list)
130 OVS_PRINTF_FORMAT(2, 0);
131 OVS_NO_RETURN
void ovs_fatal(int err_no
, const char *format
, ...)
132 OVS_PRINTF_FORMAT(2, 3);
133 OVS_NO_RETURN
void ovs_fatal_valist(int err_no
, const char *format
, va_list)
134 OVS_PRINTF_FORMAT(2, 0);
135 void ovs_error(int err_no
, const char *format
, ...) OVS_PRINTF_FORMAT(2, 3);
136 void ovs_error_valist(int err_no
, const char *format
, va_list)
137 OVS_PRINTF_FORMAT(2, 0);
138 const char *ovs_retval_to_string(int);
139 const char *ovs_strerror(int);
140 void ovs_hex_dump(FILE *, const void *, size_t, uintptr_t offset
, bool ascii
);
142 bool str_to_int(const char *, int base
, int *);
143 bool str_to_long(const char *, int base
, long *);
144 bool str_to_llong(const char *, int base
, long long *);
145 bool str_to_uint(const char *, int base
, unsigned int *);
147 bool ovs_scan(const char *s
, const char *format
, ...) OVS_SCANF_FORMAT(2, 3);
148 bool ovs_scan_len(const char *s
, int *n
, const char *format
, ...);
150 bool str_to_double(const char *, double *);
152 int hexit_value(int c
);
153 uintmax_t hexits_value(const char *s
, size_t n
, bool *ok
);
155 int parse_int_string(const char *s
, uint8_t *valuep
, int field_width
,
158 const char *english_list_delimiter(size_t index
, size_t total
);
162 char *dir_name(const char *file_name
);
163 char *base_name(const char *file_name
);
165 char *abs_file_name(const char *dir
, const char *file_name
);
167 char *follow_symlinks(const char *filename
);
169 void ignore(bool x OVS_UNUSED
);
173 /* Returns the number of trailing 0-bits in 'n'. Undefined if 'n' == 0. */
178 /* With GCC 4.7 on 32-bit x86, if a 32-bit integer is passed as 'n', using
179 * a plain __builtin_ctzll() here always generates an out-of-line function
180 * call. The test below helps it to emit a single 'bsf' instruction. */
181 return (__builtin_constant_p(n
<= UINT32_MAX
) && n
<= UINT32_MAX
183 : __builtin_ctzll(n
));
187 raw_clz64(uint64_t n
)
189 return __builtin_clzll(n
);
197 _BitScanForward64(&r
, n
);
200 unsigned long low
= n
, high
, r
= 0;
201 if (_BitScanForward(&r
, low
)) {
205 _BitScanForward(&r
, high
);
211 raw_clz64(uint64_t n
)
215 _BitScanReverse64(&r
, n
);
218 unsigned long low
, high
= n
>> 32, r
= 0;
219 if (_BitScanReverse(&r
, high
)) {
223 _BitScanReverse(&r
, low
);
228 /* Defined in util.c. */
229 int raw_ctz(uint64_t n
);
230 int raw_clz64(uint64_t n
);
233 /* Returns the number of trailing 0-bits in 'n', or 32 if 'n' is 0. */
237 return n
? raw_ctz(n
) : 32;
240 /* Returns the number of trailing 0-bits in 'n', or 64 if 'n' is 0. */
244 return n
? raw_ctz(n
) : 64;
247 /* Returns the number of leading 0-bits in 'n', or 32 if 'n' is 0. */
251 return n
? raw_clz64(n
) - 32 : 32;
254 /* Returns the number of leading 0-bits in 'n', or 64 if 'n' is 0. */
258 return n
? raw_clz64(n
) : 64;
261 /* Given a word 'n', calculates floor(log_2('n')). This is equivalent
262 * to finding the bit position of the most significant one bit in 'n'. It is
263 * an error to call this function with 'n' == 0. */
265 log_2_floor(uint64_t n
)
267 return 63 - raw_clz64(n
);
270 /* Given a word 'n', calculates ceil(log_2('n')). It is an error to
271 * call this function with 'n' == 0. */
273 log_2_ceil(uint64_t n
)
275 return log_2_floor(n
) + !is_pow2(n
);
278 /* unsigned int count_1bits(uint64_t x):
280 * Returns the number of 1-bits in 'x', between 0 and 64 inclusive. */
281 #if UINTPTR_MAX == UINT64_MAX
282 static inline unsigned int
283 count_1bits(uint64_t x
)
285 #if __GNUC__ >= 4 && __POPCNT__
286 return __builtin_popcountll(x
);
288 /* This portable implementation is the fastest one we know of for 64
289 * bits, and about 3x faster than GCC 4.7 __builtin_popcountll(). */
290 const uint64_t h55
= UINT64_C(0x5555555555555555);
291 const uint64_t h33
= UINT64_C(0x3333333333333333);
292 const uint64_t h0F
= UINT64_C(0x0F0F0F0F0F0F0F0F);
293 const uint64_t h01
= UINT64_C(0x0101010101010101);
294 x
-= (x
>> 1) & h55
; /* Count of each 2 bits in-place. */
295 x
= (x
& h33
) + ((x
>> 2) & h33
); /* Count of each 4 bits in-place. */
296 x
= (x
+ (x
>> 4)) & h0F
; /* Count of each 8 bits in-place. */
297 return (x
* h01
) >> 56; /* Sum of all bytes. */
300 #else /* Not 64-bit. */
301 #if __GNUC__ >= 4 && __POPCNT__
302 static inline unsigned int
303 count_1bits_32__(uint32_t x
)
305 return __builtin_popcount(x
);
308 #define NEED_COUNT_1BITS_8 1
309 extern const uint8_t count_1bits_8
[256];
310 static inline unsigned int
311 count_1bits_32__(uint32_t x
)
313 /* This portable implementation is the fastest one we know of for 32 bits,
314 * and faster than GCC __builtin_popcount(). */
315 return (count_1bits_8
[x
& 0xff] +
316 count_1bits_8
[(x
>> 8) & 0xff] +
317 count_1bits_8
[(x
>> 16) & 0xff] +
318 count_1bits_8
[x
>> 24]);
321 static inline unsigned int
322 count_1bits(uint64_t x
)
324 return count_1bits_32__(x
) + count_1bits_32__(x
>> 32);
328 /* Returns the rightmost 1-bit in 'x' (e.g. 01011000 => 00001000), or 0 if 'x'
330 static inline uintmax_t
331 rightmost_1bit(uintmax_t x
)
336 /* Returns 'x' with its rightmost 1-bit changed to a zero (e.g. 01011000 =>
337 * 01010000), or 0 if 'x' is 0. */
338 static inline uintmax_t
339 zero_rightmost_1bit(uintmax_t x
)
344 /* Returns the index of the rightmost 1-bit in 'x' (e.g. 01011000 => 3), or an
345 * undefined value if 'x' is 0. */
347 rightmost_1bit_idx(uint64_t x
)
352 /* Returns the index of the leftmost 1-bit in 'x' (e.g. 01011000 => 6), or an
353 * undefined value if 'x' is 0. */
354 static inline uint32_t
355 leftmost_1bit_idx(uint64_t x
)
357 return log_2_floor(x
);
360 /* Return a ovs_be32 prefix in network byte order with 'plen' highest bits set.
361 * Shift with 32 is undefined behavior, but we rather use 64-bit shift than
363 static inline ovs_be32
be32_prefix_mask(int plen
)
365 return htonl((uint64_t)UINT32_MAX
<< (32 - plen
));
368 bool is_all_zeros(const void *, size_t);
369 bool is_all_ones(const void *, size_t);
370 void bitwise_copy(const void *src
, unsigned int src_len
, unsigned int src_ofs
,
371 void *dst
, unsigned int dst_len
, unsigned int dst_ofs
,
372 unsigned int n_bits
);
373 void bitwise_zero(void *dst_
, unsigned int dst_len
, unsigned dst_ofs
,
374 unsigned int n_bits
);
375 void bitwise_one(void *dst_
, unsigned int dst_len
, unsigned dst_ofs
,
376 unsigned int n_bits
);
377 bool bitwise_is_all_zeros(const void *, unsigned int len
, unsigned int ofs
,
378 unsigned int n_bits
);
379 unsigned int bitwise_scan(const void *, unsigned int len
,
380 bool target
, unsigned int start
, unsigned int end
);
381 int bitwise_rscan(const void *, unsigned int len
, bool target
,
383 void bitwise_put(uint64_t value
,
384 void *dst
, unsigned int dst_len
, unsigned int dst_ofs
,
385 unsigned int n_bits
);
386 uint64_t bitwise_get(const void *src
, unsigned int src_len
,
387 unsigned int src_ofs
, unsigned int n_bits
);
388 bool bitwise_get_bit(const void *src
, unsigned int len
, unsigned int ofs
);
389 void bitwise_put0(void *dst
, unsigned int len
, unsigned int ofs
);
390 void bitwise_put1(void *dst
, unsigned int len
, unsigned int ofs
);
391 void bitwise_put_bit(void *dst
, unsigned int len
, unsigned int ofs
, bool);
392 void bitwise_toggle_bit(void *dst
, unsigned int len
, unsigned int ofs
);
394 /* Returns non-zero if the parameters have equal value. */
396 ovs_u128_equals(const ovs_u128 a
, const ovs_u128 b
)
398 return (a
.u64
.hi
== b
.u64
.hi
) && (a
.u64
.lo
== b
.u64
.lo
);
401 /* Returns true if 'val' is 0. */
403 ovs_u128_is_zero(const ovs_u128 val
)
405 return !(val
.u64
.hi
|| val
.u64
.lo
);
408 /* Returns true if 'val' is all ones. */
410 ovs_u128_is_ones(const ovs_u128 val
)
412 return ovs_u128_equals(val
, OVS_U128_MAX
);
415 /* Returns non-zero if the parameters have equal value. */
417 ovs_be128_equals(const ovs_be128 a
, const ovs_be128 b
)
419 return (a
.be64
.hi
== b
.be64
.hi
) && (a
.be64
.lo
== b
.be64
.lo
);
422 /* Returns true if 'val' is 0. */
424 ovs_be128_is_zero(const ovs_be128 val
)
426 return !(val
.be64
.hi
|| val
.be64
.lo
);
429 static inline ovs_u128
430 ovs_u128_and(const ovs_u128 a
, const ovs_u128 b
)
434 dst
.u64
.hi
= a
.u64
.hi
& b
.u64
.hi
;
435 dst
.u64
.lo
= a
.u64
.lo
& b
.u64
.lo
;
440 void xsleep(unsigned int seconds
);
442 bool is_stdout_a_tty(void);
446 char *ovs_format_message(int error
);
447 char *ovs_lasterror_to_string(void);
448 int ftruncate(int fd
, off_t length
);