2 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014 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.
29 #include "byte-order.h"
31 #include "openvswitch/types.h"
35 #define va_copy __va_copy
37 #define va_copy(dst, src) ((dst) = (src))
42 #define BUILD_ASSERT(EXPR) ((void) 0)
43 #define BUILD_ASSERT_DECL(EXPR) extern int (*build_assert(void))[1]
44 #elif !defined(__cplusplus)
45 /* Build-time assertion building block. */
46 #define BUILD_ASSERT__(EXPR) \
47 sizeof(struct { unsigned int build_assert_failed : (EXPR) ? 1 : -1; })
49 /* Build-time assertion for use in a statement context. */
50 #define BUILD_ASSERT(EXPR) (void) BUILD_ASSERT__(EXPR)
52 /* Build-time assertion for use in a declaration context. */
53 #define BUILD_ASSERT_DECL(EXPR) \
54 extern int (*build_assert(void))[BUILD_ASSERT__(EXPR)]
55 #else /* __cplusplus */
56 #include <boost/static_assert.hpp>
57 #define BUILD_ASSERT BOOST_STATIC_ASSERT
58 #define BUILD_ASSERT_DECL BOOST_STATIC_ASSERT
59 #endif /* __cplusplus */
62 #define BUILD_ASSERT_GCCONLY(EXPR) BUILD_ASSERT(EXPR)
63 #define BUILD_ASSERT_DECL_GCCONLY(EXPR) BUILD_ASSERT_DECL(EXPR)
65 #define BUILD_ASSERT_GCCONLY(EXPR) ((void) 0)
66 #define BUILD_ASSERT_DECL_GCCONLY(EXPR) ((void) 0)
69 /* Like the standard assert macro, except writes the failure message to the
72 #define ovs_assert(CONDITION) \
73 if (!OVS_LIKELY(CONDITION)) { \
74 ovs_assert_failure(SOURCE_LOCATOR, __func__, #CONDITION); \
77 #define ovs_assert(CONDITION) ((void) (CONDITION))
79 NO_RETURN void ovs_assert_failure(const char *, const char *, const char *);
81 /* Casts 'pointer' to 'type' and issues a compiler warning if the cast changes
82 * anything other than an outermost "const" or "volatile" qualifier.
84 * The cast to int is present only to suppress an "expression using sizeof
85 * bool" warning from "sparse" (see
86 * http://permalink.gmane.org/gmane.comp.parsers.sparse/2967). */
87 #define CONST_CAST(TYPE, POINTER) \
88 ((void) sizeof ((int) ((POINTER) == (TYPE) (POINTER))), \
91 extern char *program_name;
93 #define __ARRAY_SIZE_NOCHECK(ARRAY) (sizeof(ARRAY) / sizeof((ARRAY)[0]))
95 /* return 0 for array types, 1 otherwise */
96 #define __ARRAY_CHECK(ARRAY) \
97 !__builtin_types_compatible_p(typeof(ARRAY), typeof(&ARRAY[0]))
99 /* compile-time fail if not array */
100 #define __ARRAY_FAIL(ARRAY) (sizeof(char[-2*!__ARRAY_CHECK(ARRAY)]))
101 #define __ARRAY_SIZE(ARRAY) \
102 __builtin_choose_expr(__ARRAY_CHECK(ARRAY), \
103 __ARRAY_SIZE_NOCHECK(ARRAY), __ARRAY_FAIL(ARRAY))
105 #define __ARRAY_SIZE(ARRAY) __ARRAY_SIZE_NOCHECK(ARRAY)
108 /* Returns the number of elements in ARRAY. */
109 #define ARRAY_SIZE(ARRAY) __ARRAY_SIZE(ARRAY)
111 /* Returns X / Y, rounding up. X must be nonnegative to round correctly. */
112 #define DIV_ROUND_UP(X, Y) (((X) + ((Y) - 1)) / (Y))
114 /* Returns X rounded up to the nearest multiple of Y. */
115 #define ROUND_UP(X, Y) (DIV_ROUND_UP(X, Y) * (Y))
117 /* Returns the least number that, when added to X, yields a multiple of Y. */
118 #define PAD_SIZE(X, Y) (ROUND_UP(X, Y) - (X))
120 /* Returns X rounded down to the nearest multiple of Y. */
121 #define ROUND_DOWN(X, Y) ((X) / (Y) * (Y))
123 /* Returns true if X is a power of 2, otherwise false. */
124 #define IS_POW2(X) ((X) && !((X) & ((X) - 1)))
132 /* Returns X rounded up to a power of 2. X must be a constant expression. */
133 #define ROUND_UP_POW2(X) RUP2__(X)
134 #define RUP2__(X) (RUP2_1(X) + 1)
135 #define RUP2_1(X) (RUP2_2(X) | (RUP2_2(X) >> 16))
136 #define RUP2_2(X) (RUP2_3(X) | (RUP2_3(X) >> 8))
137 #define RUP2_3(X) (RUP2_4(X) | (RUP2_4(X) >> 4))
138 #define RUP2_4(X) (RUP2_5(X) | (RUP2_5(X) >> 2))
139 #define RUP2_5(X) (RUP2_6(X) | (RUP2_6(X) >> 1))
140 #define RUP2_6(X) ((X) - 1)
142 /* Returns X rounded down to a power of 2. X must be a constant expression. */
143 #define ROUND_DOWN_POW2(X) RDP2__(X)
144 #define RDP2__(X) (RDP2_1(X) - (RDP2_1(X) >> 1))
145 #define RDP2_1(X) (RDP2_2(X) | (RDP2_2(X) >> 16))
146 #define RDP2_2(X) (RDP2_3(X) | (RDP2_3(X) >> 8))
147 #define RDP2_3(X) (RDP2_4(X) | (RDP2_4(X) >> 4))
148 #define RDP2_4(X) (RDP2_5(X) | (RDP2_5(X) >> 2))
149 #define RDP2_5(X) ( (X) | ( (X) >> 1))
151 /* This system's cache line size, in bytes.
152 * Being wrong hurts performance but not correctness. */
153 #define CACHE_LINE_SIZE 64
154 BUILD_ASSERT_DECL(IS_POW2(CACHE_LINE_SIZE));
157 ovs_prefetch_range(const void *start, size_t size)
159 const char *addr = (const char *)start;
162 for (ofs = 0; ofs < size; ofs += CACHE_LINE_SIZE) {
163 OVS_PREFETCH(addr + ofs);
168 #define MIN(X, Y) ((X) < (Y) ? (X) : (Y))
172 #define MAX(X, Y) ((X) > (Y) ? (X) : (Y))
175 #define OVS_NOT_REACHED() abort()
177 /* Expands to a string that looks like "<file>:<line>", e.g. "tmp.c:10".
179 * See http://c-faq.com/ansi/stringize.html for an explanation of STRINGIZE and
181 #define SOURCE_LOCATOR __FILE__ ":" STRINGIZE(__LINE__)
182 #define STRINGIZE(ARG) STRINGIZE2(ARG)
183 #define STRINGIZE2(ARG) #ARG
185 /* Given a pointer-typed lvalue OBJECT, expands to a pointer type that may be
186 * assigned to OBJECT. */
188 #define OVS_TYPEOF(OBJECT) typeof(OBJECT)
190 #define OVS_TYPEOF(OBJECT) void *
193 /* Given OBJECT of type pointer-to-structure, expands to the offset of MEMBER
194 * within an instance of the structure.
196 * The GCC-specific version avoids the technicality of undefined behavior if
197 * OBJECT is null, invalid, or not yet initialized. This makes some static
198 * checkers (like Coverity) happier. But the non-GCC version does not actually
199 * dereference any pointer, so it would be surprising for it to cause any
200 * problems in practice.
203 #define OBJECT_OFFSETOF(OBJECT, MEMBER) offsetof(typeof(*(OBJECT)), MEMBER)
205 #define OBJECT_OFFSETOF(OBJECT, MEMBER) \
206 ((char *) &(OBJECT)->MEMBER - (char *) (OBJECT))
209 /* Given POINTER, the address of the given MEMBER in a STRUCT object, returns
210 the STRUCT object. */
211 #define CONTAINER_OF(POINTER, STRUCT, MEMBER) \
212 ((STRUCT *) (void *) ((char *) (POINTER) - offsetof (STRUCT, MEMBER)))
214 /* Given POINTER, the address of the given MEMBER within an object of the type
215 * that that OBJECT points to, returns OBJECT as an assignment-compatible
216 * pointer type (either the correct pointer type or "void *"). OBJECT must be
219 * This is the same as CONTAINER_OF except that it infers the structure type
220 * from the type of '*OBJECT'. */
221 #define OBJECT_CONTAINING(POINTER, OBJECT, MEMBER) \
222 ((OVS_TYPEOF(OBJECT)) (void *) \
223 ((char *) (POINTER) - OBJECT_OFFSETOF(OBJECT, MEMBER)))
225 /* Given POINTER, the address of the given MEMBER within an object of the type
226 * that that OBJECT points to, assigns the address of the outer object to
227 * OBJECT, which must be an lvalue.
229 * Evaluates to (void) 0 as the result is not to be used. */
230 #define ASSIGN_CONTAINER(OBJECT, POINTER, MEMBER) \
231 ((OBJECT) = OBJECT_CONTAINING(POINTER, OBJECT, MEMBER), (void) 0)
233 /* As explained in the comment above OBJECT_OFFSETOF(), non-GNUC compilers
234 * like MSVC will complain about un-initialized variables if OBJECT
235 * hasn't already been initialized. To prevent such warnings, INIT_CONTAINER()
236 * can be used as a wrapper around ASSIGN_CONTAINER. */
237 #define INIT_CONTAINER(OBJECT, POINTER, MEMBER) \
238 ((OBJECT) = NULL, ASSIGN_CONTAINER(OBJECT, POINTER, MEMBER))
240 /* Given ATTR, and TYPE, cast the ATTR to TYPE by first casting ATTR to
241 * (void *). This is to suppress the alignment warning issued by clang. */
242 #define ALIGNED_CAST(TYPE, ATTR) ((TYPE) (void *) (ATTR))
244 /* Use "%"PRIuSIZE to format size_t with printf(). */
246 #define PRIdSIZE "Id"
247 #define PRIiSIZE "Ii"
248 #define PRIoSIZE "Io"
249 #define PRIuSIZE "Iu"
250 #define PRIxSIZE "Ix"
251 #define PRIXSIZE "IX"
253 #define PRIdSIZE "zd"
254 #define PRIiSIZE "zi"
255 #define PRIoSIZE "zo"
256 #define PRIuSIZE "zu"
257 #define PRIxSIZE "zx"
258 #define PRIXSIZE "zX"
262 typedef uint32_t HANDLE;
269 void set_program_name__(const char *name, const char *version,
270 const char *date, const char *time);
271 #define set_program_name(name) \
272 set_program_name__(name, VERSION, __DATE__, __TIME__)
274 const char *get_subprogram_name(void);
275 void set_subprogram_name(const char *format, ...) PRINTF_FORMAT(1, 2);
277 const char *get_program_version(void);
278 void ovs_print_version(uint8_t min_ofp, uint8_t max_ofp);
280 NO_RETURN void out_of_memory(void);
281 void *xmalloc(size_t) MALLOC_LIKE;
282 void *xcalloc(size_t, size_t) MALLOC_LIKE;
283 void *xzalloc(size_t) MALLOC_LIKE;
284 void *xrealloc(void *, size_t);
285 void *xmemdup(const void *, size_t) MALLOC_LIKE;
286 char *xmemdup0(const char *, size_t) MALLOC_LIKE;
287 char *xstrdup(const char *) MALLOC_LIKE;
288 char *xasprintf(const char *format, ...) PRINTF_FORMAT(1, 2) MALLOC_LIKE;
289 char *xvasprintf(const char *format, va_list) PRINTF_FORMAT(1, 0) MALLOC_LIKE;
290 void *x2nrealloc(void *p, size_t *n, size_t s);
292 void *xmalloc_cacheline(size_t) MALLOC_LIKE;
293 void *xzalloc_cacheline(size_t) MALLOC_LIKE;
294 void free_cacheline(void *);
296 void ovs_strlcpy(char *dst, const char *src, size_t size);
297 void ovs_strzcpy(char *dst, const char *src, size_t size);
299 NO_RETURN void ovs_abort(int err_no, const char *format, ...)
301 NO_RETURN void ovs_abort_valist(int err_no, const char *format, va_list)
303 NO_RETURN void ovs_fatal(int err_no, const char *format, ...)
305 NO_RETURN void ovs_fatal_valist(int err_no, const char *format, va_list)
307 void ovs_error(int err_no, const char *format, ...) PRINTF_FORMAT(2, 3);
308 void ovs_error_valist(int err_no, const char *format, va_list)
310 const char *ovs_retval_to_string(int);
311 const char *ovs_strerror(int);
312 void ovs_hex_dump(FILE *, const void *, size_t, uintptr_t offset, bool ascii);
314 bool str_to_int(const char *, int base, int *);
315 bool str_to_long(const char *, int base, long *);
316 bool str_to_llong(const char *, int base, long long *);
317 bool str_to_uint(const char *, int base, unsigned int *);
319 bool ovs_scan(const char *s, const char *format, ...) SCANF_FORMAT(2, 3);
321 bool str_to_double(const char *, double *);
323 int hexit_value(int c);
324 uintmax_t hexits_value(const char *s, size_t n, bool *ok);
326 const char *english_list_delimiter(size_t index, size_t total);
330 char *dir_name(const char *file_name);
331 char *base_name(const char *file_name);
333 char *abs_file_name(const char *dir, const char *file_name);
335 char *follow_symlinks(const char *filename);
337 void ignore(bool x OVS_UNUSED);
341 /* Returns the number of trailing 0-bits in 'n'. Undefined if 'n' == 0. */
346 /* With GCC 4.7 on 32-bit x86, if a 32-bit integer is passed as 'n', using
347 * a plain __builtin_ctzll() here always generates an out-of-line function
348 * call. The test below helps it to emit a single 'bsf' instruction. */
349 return (__builtin_constant_p(n <= UINT32_MAX) && n <= UINT32_MAX
351 : __builtin_ctzll(n));
355 raw_clz64(uint64_t n)
357 return __builtin_clzll(n);
365 _BitScanForward64(&r, n);
368 uint32_t low = n, high, r = 0;
369 if (_BitScanForward(&r, low)) {
373 _BitScanForward(&r, high);
379 raw_clz64(uint64_t n)
383 _BitScanReverse64(&r, n);
386 uint32_t low, high = n >> 32, r = 0;
387 if (_BitScanReverse(&r, high)) {
391 _BitScanReverse(&r, low);
396 /* Defined in util.c. */
397 int raw_ctz(uint64_t n);
398 int raw_clz64(uint64_t n);
401 /* Returns the number of trailing 0-bits in 'n', or 32 if 'n' is 0. */
405 return n ? raw_ctz(n) : 32;
408 /* Returns the number of trailing 0-bits in 'n', or 64 if 'n' is 0. */
412 return n ? raw_ctz(n) : 64;
415 /* Returns the number of leading 0-bits in 'n', or 32 if 'n' is 0. */
419 return n ? raw_clz64(n) - 32 : 32;
422 /* Returns the number of leading 0-bits in 'n', or 64 if 'n' is 0. */
426 return n ? raw_clz64(n) : 64;
429 /* Given a word 'n', calculates floor(log_2('n')). This is equivalent
430 * to finding the bit position of the most significant one bit in 'n'. It is
431 * an error to call this function with 'n' == 0. */
433 log_2_floor(uint64_t n)
435 return 63 - raw_clz64(n);
438 /* Given a word 'n', calculates ceil(log_2('n')). It is an error to
439 * call this function with 'n' == 0. */
441 log_2_ceil(uint64_t n)
443 return log_2_floor(n) + !is_pow2(n);
446 /* unsigned int count_1bits(uint64_t x):
448 * Returns the number of 1-bits in 'x', between 0 and 64 inclusive. */
449 #if UINTPTR_MAX == UINT64_MAX
450 static inline unsigned int
451 count_1bits(uint64_t x)
453 #if __GNUC__ >= 4 && __POPCNT__
454 return __builtin_popcountll(x);
456 /* This portable implementation is the fastest one we know of for 64
457 * bits, and about 3x faster than GCC 4.7 __builtin_popcountll(). */
458 const uint64_t h55 = UINT64_C(0x5555555555555555);
459 const uint64_t h33 = UINT64_C(0x3333333333333333);
460 const uint64_t h0F = UINT64_C(0x0F0F0F0F0F0F0F0F);
461 const uint64_t h01 = UINT64_C(0x0101010101010101);
462 x -= (x >> 1) & h55; /* Count of each 2 bits in-place. */
463 x = (x & h33) + ((x >> 2) & h33); /* Count of each 4 bits in-place. */
464 x = (x + (x >> 4)) & h0F; /* Count of each 8 bits in-place. */
465 return (x * h01) >> 56; /* Sum of all bytes. */
468 #else /* Not 64-bit. */
469 #if __GNUC__ >= 4 && __POPCNT__
470 static inline unsigned int
471 count_1bits_32__(uint32_t x)
473 return __builtin_popcount(x);
476 #define NEED_COUNT_1BITS_8 1
477 extern const uint8_t count_1bits_8[256];
478 static inline unsigned int
479 count_1bits_32__(uint32_t x)
481 /* This portable implementation is the fastest one we know of for 32 bits,
482 * and faster than GCC __builtin_popcount(). */
483 return (count_1bits_8[x & 0xff] +
484 count_1bits_8[(x >> 8) & 0xff] +
485 count_1bits_8[(x >> 16) & 0xff] +
486 count_1bits_8[x >> 24]);
489 static inline unsigned int
490 count_1bits(uint64_t x)
492 return count_1bits_32__(x) + count_1bits_32__(x >> 32);
496 /* Returns the rightmost 1-bit in 'x' (e.g. 01011000 => 00001000), or 0 if 'x'
498 static inline uintmax_t
499 rightmost_1bit(uintmax_t x)
504 /* Returns 'x' with its rightmost 1-bit changed to a zero (e.g. 01011000 =>
505 * 01010000), or 0 if 'x' is 0. */
506 static inline uintmax_t
507 zero_rightmost_1bit(uintmax_t x)
512 /* Returns the index of the rightmost 1-bit in 'x' (e.g. 01011000 => 3), or 32
515 * Unlike the other functions for rightmost 1-bits, this function only works
516 * with 32-bit integers. */
518 rightmost_1bit_idx(uint32_t x)
523 /* Returns the index of the leftmost 1-bit in 'x' (e.g. 01011000 => 6), or 32
526 * This function only works with 32-bit integers. */
527 static inline uint32_t
528 leftmost_1bit_idx(uint32_t x)
530 return x ? log_2_floor(x) : 32;
533 /* Return a ovs_be32 prefix in network byte order with 'plen' highest bits set.
534 * Shift with 32 is undefined behavior, but we rather use 64-bit shift than
536 static inline ovs_be32 be32_prefix_mask(int plen)
538 return htonl((uint64_t)UINT32_MAX << (32 - plen));
541 bool is_all_zeros(const void *, size_t);
542 bool is_all_ones(const void *, size_t);
543 void bitwise_copy(const void *src, unsigned int src_len, unsigned int src_ofs,
544 void *dst, unsigned int dst_len, unsigned int dst_ofs,
545 unsigned int n_bits);
546 void bitwise_zero(void *dst_, unsigned int dst_len, unsigned dst_ofs,
547 unsigned int n_bits);
548 void bitwise_one(void *dst_, unsigned int dst_len, unsigned dst_ofs,
549 unsigned int n_bits);
550 bool bitwise_is_all_zeros(const void *, unsigned int len, unsigned int ofs,
551 unsigned int n_bits);
552 unsigned int bitwise_scan(const void *, unsigned int len,
553 bool target, unsigned int start, unsigned int end);
554 void bitwise_put(uint64_t value,
555 void *dst, unsigned int dst_len, unsigned int dst_ofs,
556 unsigned int n_bits);
557 uint64_t bitwise_get(const void *src, unsigned int src_len,
558 unsigned int src_ofs, unsigned int n_bits);
560 void xsleep(unsigned int seconds);
564 char *ovs_format_message(int error);
565 char *ovs_lasterror_to_string(void);
566 int ftruncate(int fd, off_t length);