lib: Move compiler.h to <openvswitch/compiler.h>

The following macros are renamed to avoid conflicts with other headers:
 * WARN_UNUSED_RESULT to OVS_WARN_UNUSED_RESULT
 * PRINTF_FORMAT to OVS_PRINTF_FORMAT
 * NO_RETURN to OVS_NO_RETURN

Signed-off-by: Thomas Graf <[email protected]>
Acked-by: Ben Pfaff <[email protected]>

include/openvswitch/automake.mk

@@ -1,5 +1,6 @@
 openvswitchincludedir = $(includedir)/openvswitch
 openvswitchinclude_HEADERS = \
+	include/openvswitch/compiler.h \
 	include/openvswitch/types.h \
 	include/openvswitch/util.h \
 	include/openvswitch/version.h

include/openvswitch/compiler.h

@@ -0,0 +1,224 @@
+/*
+ * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014 Nicira, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef OPENVSWITCH_COMPILER_H
+#define OPENVSWITCH_COMPILER_H 1
+
+#ifndef __has_feature
+  #define __has_feature(x) 0
+#endif
+#ifndef __has_extension
+  #define __has_extension(x) 0
+#endif
+
+/* To make OVS_NO_RETURN portable across gcc/clang and MSVC, it should be
+ * added at the beginning of the function declaration. */
+#if __GNUC__ && !__CHECKER__
+#define OVS_NO_RETURN __attribute__((__noreturn__))
+#elif _MSC_VER
+#define OVS_NO_RETURN __declspec(noreturn)
+#else
+#define OVS_NO_RETURN
+#endif
+
+#if __GNUC__ && !__CHECKER__
+#define OVS_UNUSED __attribute__((__unused__))
+#define OVS_PRINTF_FORMAT(FMT, ARG1) __attribute__((__format__(printf, FMT, ARG1)))
+#define OVS_SCANF_FORMAT(FMT, ARG1) __attribute__((__format__(scanf, FMT, ARG1)))
+#define OVS_WARN_UNUSED_RESULT __attribute__((__warn_unused_result__))
+#define OVS_LIKELY(CONDITION) __builtin_expect(!!(CONDITION), 1)
+#define OVS_UNLIKELY(CONDITION) __builtin_expect(!!(CONDITION), 0)
+#else
+#define OVS_UNUSED
+#define OVS_PRINTF_FORMAT(FMT, ARG1)
+#define OVS_SCANF_FORMAT(FMT, ARG1)
+#define OVS_WARN_UNUSED_RESULT
+#define OVS_LIKELY(CONDITION) (!!(CONDITION))
+#define OVS_UNLIKELY(CONDITION) (!!(CONDITION))
+#endif
+
+#if __has_feature(c_thread_safety_attributes)
+/* "clang" annotations for thread safety check.
+ *
+ * OVS_LOCKABLE indicates that the struct contains mutex element
+ * which can be locked by functions like ovs_mutex_lock().
+ *
+ * Below, the word MUTEX stands for the name of an object with an OVS_LOCKABLE
+ * struct type.  It can also be a comma-separated list of multiple structs,
+ * e.g. to require a function to hold multiple locks while invoked.
+ *
+ *
+ * On a variable:
+ *
+ *    - OVS_GUARDED indicates that the variable may only be accessed some mutex
+ *      is held.
+ *
+ *    - OVS_GUARDED_BY(MUTEX) indicates that the variable may only be accessed
+ *      while the specific MUTEX is held.
+ *
+ *
+ * On a variable A of mutex type:
+ *
+ *    - OVS_ACQ_BEFORE(B), where B is a mutex or a comma-separated list of
+ *      mutexes, declare that if both A and B are acquired at the same time,
+ *      then A must be acquired before B.  That is, B nests inside A.
+ *
+ *    - OVS_ACQ_AFTER(B) is the opposite of OVS_ACQ_BEFORE(B), that is, it
+ *      declares that A nests inside B.
+ *
+ *
+ * On a function, the following attributes apply to mutexes:
+ *
+ *    - OVS_ACQUIRES(MUTEX) indicate that the function must be called without
+ *      holding MUTEX and that it returns holding MUTEX.
+ *
+ *    - OVS_RELEASES(MUTEX) indicates that the function may only be called with
+ *      MUTEX held and that it returns with MUTEX released.  It can be used for
+ *      all types of MUTEX.
+ *
+ *    - OVS_TRY_LOCK(RETVAL, MUTEX) indicate that the function will try to
+ *      acquire MUTEX.  RETVAL is an integer or boolean value specifying the
+ *      return value of a successful lock acquisition.
+ *
+ *    - OVS_REQUIRES(MUTEX) indicate that the function may only be called with
+ *      MUTEX held and that the function does not release MUTEX.
+ *
+ *    - OVS_EXCLUDED(MUTEX) indicates that the function may only be called when
+ *      MUTEX is not held.
+ *
+ *
+ * The following variants, with the same syntax, apply to reader-writer locks:
+ *
+ *    mutex                rwlock, for reading  rwlock, for writing
+ *    -------------------  -------------------  -------------------
+ *    OVS_ACQUIRES         OVS_ACQ_RDLOCK       OVS_ACQ_WRLOCK
+ *    OVS_RELEASES         OVS_RELEASES         OVS_RELEASES
+ *    OVS_TRY_LOCK         OVS_TRY_RDLOCK       OVS_TRY_WRLOCK
+ *    OVS_REQUIRES         OVS_REQ_RDLOCK       OVS_REQ_WRLOCK
+ *    OVS_EXCLUDED         OVS_EXCLUDED         OVS_EXCLUDED
+ */
+#define OVS_LOCKABLE __attribute__((lockable))
+#define OVS_REQ_RDLOCK(...) __attribute__((shared_locks_required(__VA_ARGS__)))
+#define OVS_ACQ_RDLOCK(...) __attribute__((shared_lock_function(__VA_ARGS__)))
+#define OVS_REQ_WRLOCK(...) \
+    __attribute__((exclusive_locks_required(__VA_ARGS__)))
+#define OVS_ACQ_WRLOCK(...) \
+    __attribute__((exclusive_lock_function(__VA_ARGS__)))
+#define OVS_REQUIRES(...) \
+    __attribute__((exclusive_locks_required(__VA_ARGS__)))
+#define OVS_ACQUIRES(...) \
+    __attribute__((exclusive_lock_function(__VA_ARGS__)))
+#define OVS_TRY_WRLOCK(RETVAL, ...)                              \
+    __attribute__((exclusive_trylock_function(RETVAL, __VA_ARGS__)))
+#define OVS_TRY_RDLOCK(RETVAL, ...)                          \
+    __attribute__((shared_trylock_function(RETVAL, __VA_ARGS__)))
+#define OVS_TRY_LOCK(RETVAL, ...)                                \
+    __attribute__((exclusive_trylock_function(RETVAL, __VA_ARGS__)))
+#define OVS_GUARDED __attribute__((guarded_var))
+#define OVS_GUARDED_BY(...) __attribute__((guarded_by(__VA_ARGS__)))
+#define OVS_RELEASES(...) __attribute__((unlock_function(__VA_ARGS__)))
+#define OVS_EXCLUDED(...) __attribute__((locks_excluded(__VA_ARGS__)))
+#define OVS_ACQ_BEFORE(...) __attribute__((acquired_before(__VA_ARGS__)))
+#define OVS_ACQ_AFTER(...) __attribute__((acquired_after(__VA_ARGS__)))
+#define OVS_NO_THREAD_SAFETY_ANALYSIS \
+    __attribute__((no_thread_safety_analysis))
+#else  /* not Clang */
+#define OVS_LOCKABLE
+#define OVS_REQ_RDLOCK(...)
+#define OVS_ACQ_RDLOCK(...)
+#define OVS_REQ_WRLOCK(...)
+#define OVS_ACQ_WRLOCK(...)
+#define OVS_REQUIRES(...)
+#define OVS_ACQUIRES(...)
+#define OVS_TRY_WRLOCK(...)
+#define OVS_TRY_RDLOCK(...)
+#define OVS_TRY_LOCK(...)
+#define OVS_GUARDED
+#define OVS_GUARDED_BY(...)
+#define OVS_EXCLUDED(...)
+#define OVS_RELEASES(...)
+#define OVS_ACQ_BEFORE(...)
+#define OVS_ACQ_AFTER(...)
+#define OVS_NO_THREAD_SAFETY_ANALYSIS
+#endif
+
+/* ISO C says that a C implementation may choose any integer type for an enum
+ * that is sufficient to hold all of its values.  Common ABIs (such as the
+ * System V ABI used on i386 GNU/Linux) always use a full-sized "int", even
+ * when a smaller type would suffice.
+ *
+ * In GNU C, "enum __attribute__((packed)) name { ... }" defines 'name' as an
+ * enum compatible with a type that is no bigger than necessary.  This is the
+ * intended use of OVS_PACKED_ENUM.
+ *
+ * OVS_PACKED_ENUM is intended for use only as a space optimization, since it
+ * only works with GCC.  That means that it must not be used in wire protocols
+ * or otherwise exposed outside of a single process. */
+#if __GNUC__ && !__CHECKER__
+#define OVS_PACKED_ENUM __attribute__((__packed__))
+#define HAVE_PACKED_ENUM
+#else
+#define OVS_PACKED_ENUM
+#endif
+
+#ifndef _MSC_VER
+#define OVS_PACKED(DECL) DECL __attribute__((__packed__))
+#else
+#define OVS_PACKED(DECL) __pragma(pack(push, 1)) DECL __pragma(pack(pop))
+#endif
+
+/* For defining a structure whose instances should aligned on an N-byte
+ * boundary.
+ *
+ * e.g. The following:
+ *     OVS_ALIGNED_STRUCT(64, mystruct) { ... };
+ * is equivalent to the following except that it specifies 64-byte alignment:
+ *     struct mystruct { ... };
+ */
+#ifndef _MSC_VER
+#define OVS_ALIGNED_STRUCT(N, TAG) struct __attribute__((aligned(N))) TAG
+#else
+#define OVS_ALIGNED_STRUCT(N, TAG) __declspec(align(N)) struct TAG
+#endif
+
+#ifdef _MSC_VER
+#define CCALL __cdecl
+#pragma section(".CRT$XCU",read)
+#define OVS_CONSTRUCTOR(f) \
+    static void __cdecl f(void); \
+    __declspec(allocate(".CRT$XCU")) void (__cdecl*f##_)(void) = f; \
+    static void __cdecl f(void)
+#else
+#define OVS_CONSTRUCTOR(f) \
+    static void f(void) __attribute__((constructor)); \
+    static void f(void)
+#endif
+
+/* OVS_PREFETCH() can be used to instruct the CPU to fetch the cache
+ * line containing the given address to a CPU cache.
+ * OVS_PREFETCH_WRITE() should be used when the memory is going to be
+ * written to.  Depending on the target CPU, this can generate the same
+ * instruction as OVS_PREFETCH(), or bring the data into the cache in an
+ * exclusive state. */
+#if __GNUC__
+#define OVS_PREFETCH(addr) __builtin_prefetch((addr))
+#define OVS_PREFETCH_WRITE(addr) __builtin_prefetch((addr), 1)
+#else
+#define OVS_PREFETCH(addr)
+#define OVS_PREFETCH_WRITE(addr)
+#endif
+
+#endif /* compiler.h */

lib/bundle.c

@@ -142,7 +142,7 @@ bundle_check(const struct ofpact_bundle *bundle, ofp_port_t max_ports,
  *
  * Returns NULL if successful, otherwise a malloc()'d string describing the
  * error.  The caller is responsible for freeing the returned string.*/
-static char * WARN_UNUSED_RESULT
+static char * OVS_WARN_UNUSED_RESULT
 bundle_parse__(const char *s, char **save_ptr,
                const char *fields, const char *basis, const char *algorithm,
                const char *slave_type, const char *dst,
@@ -222,7 +222,7 @@ bundle_parse__(const char *s, char **save_ptr,
  *
  * Returns NULL if successful, otherwise a malloc()'d string describing the
  * error.  The caller is responsible for freeing the returned string. */
-char * WARN_UNUSED_RESULT
+char * OVS_WARN_UNUSED_RESULT
 bundle_parse(const char *s, struct ofpbuf *ofpacts)
 {
     char *fields, *basis, *algorithm, *slave_type, *slave_delim;
@@ -249,7 +249,7 @@ bundle_parse(const char *s, struct ofpbuf *ofpacts)
  *
  * Returns NULL if successful, otherwise a malloc()'d string describing the
  * error.  The caller is responsible for freeing the returned string.*/
-char * WARN_UNUSED_RESULT
+char * OVS_WARN_UNUSED_RESULT
 bundle_parse_load(const char *s, struct ofpbuf *ofpacts)
 {
     char *fields, *basis, *algorithm, *slave_type, *dst, *slave_delim;

lib/bundle.h

@@ -44,9 +44,9 @@ ofp_port_t bundle_execute(const struct ofpact_bundle *, const struct flow *,
                         void *aux);
 enum ofperr bundle_check(const struct ofpact_bundle *, ofp_port_t max_ports,
                          const struct flow *);
-char *bundle_parse(const char *, struct ofpbuf *ofpacts) WARN_UNUSED_RESULT;
+char *bundle_parse(const char *, struct ofpbuf *ofpacts) OVS_WARN_UNUSED_RESULT;
 char *bundle_parse_load(const char *, struct ofpbuf *ofpacts)
-    WARN_UNUSED_RESULT;
+    OVS_WARN_UNUSED_RESULT;
 void bundle_format(const struct ofpact_bundle *, struct ds *);
 
 #endif /* bundle.h */

lib/command-line.h

@@ -41,7 +41,7 @@ void proctitle_init(int argc, char **argv);
 #define proctitle_set setproctitle
 #else
 void proctitle_set(const char *, ...)
-    PRINTF_FORMAT(1, 2);
+    OVS_PRINTF_FORMAT(1, 2);
 #endif
 void proctitle_restore(void);