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2 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013 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 "openvswitch/types.h"
33 #define va_copy __va_copy
35 #define va_copy(dst, src) ((dst) = (src))
40 #define BUILD_ASSERT(EXPR) ((void) 0)
41 #define BUILD_ASSERT_DECL(EXPR) extern int (*build_assert(void))[1]
42 #elif !defined(__cplusplus)
43 /* Build-time assertion building block. */
44 #define BUILD_ASSERT__(EXPR) \
45 sizeof(struct { unsigned int build_assert_failed : (EXPR) ? 1 : -1; })
47 /* Build-time assertion for use in a statement context. */
48 #define BUILD_ASSERT(EXPR) (void) BUILD_ASSERT__(EXPR)
50 /* Build-time assertion for use in a declaration context. */
51 #define BUILD_ASSERT_DECL(EXPR) \
52 extern int (*build_assert(void))[BUILD_ASSERT__(EXPR)]
53 #else /* __cplusplus */
54 #include <boost/static_assert.hpp>
55 #define BUILD_ASSERT BOOST_STATIC_ASSERT
56 #define BUILD_ASSERT_DECL BOOST_STATIC_ASSERT
57 #endif /* __cplusplus */
60 #define BUILD_ASSERT_GCCONLY(EXPR) BUILD_ASSERT(EXPR)
61 #define BUILD_ASSERT_DECL_GCCONLY(EXPR) BUILD_ASSERT_DECL(EXPR)
63 #define BUILD_ASSERT_GCCONLY(EXPR) ((void) 0)
64 #define BUILD_ASSERT_DECL_GCCONLY(EXPR) ((void) 0)
67 /* Like the standard assert macro, except:
69 * - Writes the failure message to the log.
71 * - Not affected by NDEBUG. */
72 #define ovs_assert(CONDITION) \
73 if (!OVS_LIKELY(CONDITION)) { \
74 ovs_assert_failure(SOURCE_LOCATOR, __func__, #CONDITION); \
76 void ovs_assert_failure(const char *, const char *, const char *) NO_RETURN
;
78 /* Casts 'pointer' to 'type' and issues a compiler warning if the cast changes
79 * anything other than an outermost "const" or "volatile" qualifier.
81 * The cast to int is present only to suppress an "expression using sizeof
82 * bool" warning from "sparse" (see
83 * http://permalink.gmane.org/gmane.comp.parsers.sparse/2967). */
84 #define CONST_CAST(TYPE, POINTER) \
85 ((void) sizeof ((int) ((POINTER) == (TYPE) (POINTER))), \
88 extern const char *program_name
;
90 /* Returns the number of elements in ARRAY. */
91 #define ARRAY_SIZE(ARRAY) (sizeof ARRAY / sizeof *ARRAY)
93 /* Returns X / Y, rounding up. X must be nonnegative to round correctly. */
94 #define DIV_ROUND_UP(X, Y) (((X) + ((Y) - 1)) / (Y))
96 /* Returns X rounded up to the nearest multiple of Y. */
97 #define ROUND_UP(X, Y) (DIV_ROUND_UP(X, Y) * (Y))
99 /* Returns X rounded down to the nearest multiple of Y. */
100 #define ROUND_DOWN(X, Y) ((X) / (Y) * (Y))
102 /* Returns true if X is a power of 2, otherwise false. */
103 #define IS_POW2(X) ((X) && !((X) & ((X) - 1)))
111 /* Returns X rounded up to a power of 2. X must be a constant expression. */
112 #define ROUND_UP_POW2(X) RUP2__(X)
113 #define RUP2__(X) (RUP2_1(X) + 1)
114 #define RUP2_1(X) (RUP2_2(X) | (RUP2_2(X) >> 16))
115 #define RUP2_2(X) (RUP2_3(X) | (RUP2_3(X) >> 8))
116 #define RUP2_3(X) (RUP2_4(X) | (RUP2_4(X) >> 4))
117 #define RUP2_4(X) (RUP2_5(X) | (RUP2_5(X) >> 2))
118 #define RUP2_5(X) (RUP2_6(X) | (RUP2_6(X) >> 1))
119 #define RUP2_6(X) ((X) - 1)
121 /* Returns X rounded down to a power of 2. X must be a constant expression. */
122 #define ROUND_DOWN_POW2(X) RDP2__(X)
123 #define RDP2__(X) (RDP2_1(X) - (RDP2_1(X) >> 1))
124 #define RDP2_1(X) (RDP2_2(X) | (RDP2_2(X) >> 16))
125 #define RDP2_2(X) (RDP2_3(X) | (RDP2_3(X) >> 8))
126 #define RDP2_3(X) (RDP2_4(X) | (RDP2_4(X) >> 4))
127 #define RDP2_4(X) (RDP2_5(X) | (RDP2_5(X) >> 2))
128 #define RDP2_5(X) ( (X) | ( (X) >> 1))
131 #define MIN(X, Y) ((X) < (Y) ? (X) : (Y))
135 #define MAX(X, Y) ((X) > (Y) ? (X) : (Y))
138 #define NOT_REACHED() abort()
140 /* Expands to a string that looks like "<file>:<line>", e.g. "tmp.c:10".
142 * See http://c-faq.com/ansi/stringize.html for an explanation of STRINGIZE and
144 #define SOURCE_LOCATOR __FILE__ ":" STRINGIZE(__LINE__)
145 #define STRINGIZE(ARG) STRINGIZE2(ARG)
146 #define STRINGIZE2(ARG) #ARG
148 /* Given a pointer-typed lvalue OBJECT, expands to a pointer type that may be
149 * assigned to OBJECT. */
151 #define OVS_TYPEOF(OBJECT) typeof(OBJECT)
153 #define OVS_TYPEOF(OBJECT) void *
156 /* Given OBJECT of type pointer-to-structure, expands to the offset of MEMBER
157 * within an instance of the structure.
159 * The GCC-specific version avoids the technicality of undefined behavior if
160 * OBJECT is null, invalid, or not yet initialized. This makes some static
161 * checkers (like Coverity) happier. But the non-GCC version does not actually
162 * dereference any pointer, so it would be surprising for it to cause any
163 * problems in practice.
166 #define OBJECT_OFFSETOF(OBJECT, MEMBER) offsetof(typeof(*(OBJECT)), MEMBER)
168 #define OBJECT_OFFSETOF(OBJECT, MEMBER) \
169 ((char *) &(OBJECT)->MEMBER - (char *) (OBJECT))
172 /* Given POINTER, the address of the given MEMBER in a STRUCT object, returns
173 the STRUCT object. */
174 #define CONTAINER_OF(POINTER, STRUCT, MEMBER) \
175 ((STRUCT *) (void *) ((char *) (POINTER) - offsetof (STRUCT, MEMBER)))
177 /* Given POINTER, the address of the given MEMBER within an object of the type
178 * that that OBJECT points to, returns OBJECT as an assignment-compatible
179 * pointer type (either the correct pointer type or "void *"). OBJECT must be
182 * This is the same as CONTAINER_OF except that it infers the structure type
183 * from the type of '*OBJECT'. */
184 #define OBJECT_CONTAINING(POINTER, OBJECT, MEMBER) \
185 ((OVS_TYPEOF(OBJECT)) (void *) \
186 ((char *) (POINTER) - OBJECT_OFFSETOF(OBJECT, MEMBER)))
188 /* Given POINTER, the address of the given MEMBER within an object of the type
189 * that that OBJECT points to, assigns the address of the outer object to
190 * OBJECT, which must be an lvalue.
192 * Evaluates to (void) 0 as the result is not to be used. */
193 #define ASSIGN_CONTAINER(OBJECT, POINTER, MEMBER) \
194 ((OBJECT) = OBJECT_CONTAINING(POINTER, OBJECT, MEMBER), (void) 0)
200 void set_program_name__(const char *name
, const char *version
,
201 const char *date
, const char *time
);
202 #define set_program_name(name) \
203 set_program_name__(name, VERSION, __DATE__, __TIME__)
205 const char *get_subprogram_name(void);
206 void set_subprogram_name(const char *name
);
208 const char *get_program_version(void);
209 void ovs_print_version(uint8_t min_ofp
, uint8_t max_ofp
);
211 void out_of_memory(void) NO_RETURN
;
212 void *xmalloc(size_t) MALLOC_LIKE
;
213 void *xcalloc(size_t, size_t) MALLOC_LIKE
;
214 void *xzalloc(size_t) MALLOC_LIKE
;
215 void *xrealloc(void *, size_t);
216 void *xmemdup(const void *, size_t) MALLOC_LIKE
;
217 char *xmemdup0(const char *, size_t) MALLOC_LIKE
;
218 char *xstrdup(const char *) MALLOC_LIKE
;
219 char *xasprintf(const char *format
, ...) PRINTF_FORMAT(1, 2) MALLOC_LIKE
;
220 char *xvasprintf(const char *format
, va_list) PRINTF_FORMAT(1, 0) MALLOC_LIKE
;
221 void *x2nrealloc(void *p
, size_t *n
, size_t s
);
223 void ovs_strlcpy(char *dst
, const char *src
, size_t size
);
224 void ovs_strzcpy(char *dst
, const char *src
, size_t size
);
226 void ovs_abort(int err_no
, const char *format
, ...)
227 PRINTF_FORMAT(2, 3) NO_RETURN
;
228 void ovs_abort_valist(int err_no
, const char *format
, va_list)
229 PRINTF_FORMAT(2, 0) NO_RETURN
;
230 void ovs_fatal(int err_no
, const char *format
, ...)
231 PRINTF_FORMAT(2, 3) NO_RETURN
;
232 void ovs_fatal_valist(int err_no
, const char *format
, va_list)
233 PRINTF_FORMAT(2, 0) NO_RETURN
;
234 void ovs_error(int err_no
, const char *format
, ...) PRINTF_FORMAT(2, 3);
235 void ovs_error_valist(int err_no
, const char *format
, va_list)
237 const char *ovs_retval_to_string(int);
238 const char *ovs_strerror(int);
239 void ovs_hex_dump(FILE *, const void *, size_t, uintptr_t offset
, bool ascii
);
241 bool str_to_int(const char *, int base
, int *);
242 bool str_to_long(const char *, int base
, long *);
243 bool str_to_llong(const char *, int base
, long long *);
244 bool str_to_uint(const char *, int base
, unsigned int *);
245 bool str_to_ulong(const char *, int base
, unsigned long *);
246 bool str_to_ullong(const char *, int base
, unsigned long long *);
248 bool str_to_double(const char *, double *);
250 int hexit_value(int c
);
251 unsigned int hexits_value(const char *s
, size_t n
, bool *ok
);
253 const char *english_list_delimiter(size_t index
, size_t total
);
256 char *dir_name(const char *file_name
);
257 char *base_name(const char *file_name
);
258 char *abs_file_name(const char *dir
, const char *file_name
);
260 char *xreadlink(const char *filename
);
261 char *follow_symlinks(const char *filename
);
263 void ignore(bool x OVS_UNUSED
);
267 /* Returns the number of trailing 0-bits in 'n'. Undefined if 'n' == 0.
269 * This compiles to a single machine instruction ("bsf") with GCC on x86. */
270 #if !defined(UINT_MAX) || !defined(UINT32_MAX)
271 #error "Someone screwed up the #includes."
272 #elif __GNUC__ >= 4 && UINT_MAX == UINT32_MAX
276 return __builtin_ctz(n
);
279 /* Defined in util.c. */
280 int raw_ctz(uint32_t n
);
283 /* Returns the number of trailing 0-bits in 'n', or 32 if 'n' is 0. */
287 return n
? raw_ctz(n
) : 32;
290 int log_2_floor(uint32_t);
291 int log_2_ceil(uint32_t);
292 unsigned int popcount(uint32_t);
294 /* Returns the rightmost 1-bit in 'x' (e.g. 01011000 => 00001000), or 0 if 'x'
296 static inline uintmax_t
297 rightmost_1bit(uintmax_t x
)
302 /* Returns 'x' with its rightmost 1-bit changed to a zero (e.g. 01011000 =>
303 * 01010000), or 0 if 'x' is 0. */
304 static inline uintmax_t
305 zero_rightmost_1bit(uintmax_t x
)
310 /* Returns the index of the rightmost 1-bit in 'x' (e.g. 01011000 => 3), or 32
313 * Unlike the other functions for rightmost 1-bits, this function only works
314 * with 32-bit integers. */
315 static inline uint32_t
316 rightmost_1bit_idx(uint32_t x
)
318 return x
? ctz(x
) : 32;
321 /* Returns the index of the rightmost 1-bit in 'x' (e.g. 01011000 => 6), or 32
324 * This function only works with 32-bit integers. */
325 static inline uint32_t
326 leftmost_1bit_idx(uint32_t x
)
328 return x
? log_2_floor(x
) : 32;
331 bool is_all_zeros(const uint8_t *, size_t);
332 bool is_all_ones(const uint8_t *, size_t);
333 void bitwise_copy(const void *src
, unsigned int src_len
, unsigned int src_ofs
,
334 void *dst
, unsigned int dst_len
, unsigned int dst_ofs
,
335 unsigned int n_bits
);
336 void bitwise_zero(void *dst_
, unsigned int dst_len
, unsigned dst_ofs
,
337 unsigned int n_bits
);
338 void bitwise_one(void *dst_
, unsigned int dst_len
, unsigned dst_ofs
,
339 unsigned int n_bits
);
340 bool bitwise_is_all_zeros(const void *, unsigned int len
, unsigned int ofs
,
341 unsigned int n_bits
);
342 void bitwise_put(uint64_t value
,
343 void *dst
, unsigned int dst_len
, unsigned int dst_ofs
,
344 unsigned int n_bits
);
345 uint64_t bitwise_get(const void *src
, unsigned int src_len
,
346 unsigned int src_ofs
, unsigned int n_bits
);