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Diffstat (limited to 'rubbos/app/apache2/include/apr_atomic.h')
| -rw-r--r-- | rubbos/app/apache2/include/apr_atomic.h | 314 |
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diff --git a/rubbos/app/apache2/include/apr_atomic.h b/rubbos/app/apache2/include/apr_atomic.h new file mode 100644 index 00000000..87889292 --- /dev/null +++ b/rubbos/app/apache2/include/apr_atomic.h @@ -0,0 +1,314 @@ +/* Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You 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 APR_ATOMIC_H +#define APR_ATOMIC_H + +/** + * @file apr_atomic.h + * @brief APR Atomic Operations + */ + +#include "apr.h" +#include "apr_pools.h" + +/* Platform includes for atomics */ +#if defined(NETWARE) || defined(__MVS__) /* OS/390 */ +#include <stdlib.h> +#elif defined(__FreeBSD__) +#include <machine/atomic.h> +#endif + +#ifdef __cplusplus +extern "C" { +#endif + +/** + * @defgroup apr_atomic Atomic Operations + * @ingroup APR + * @{ + */ + +/* easiest way to get these documented for the moment */ +#if defined(DOXYGEN) +/** + * structure for holding a atomic value. + * this number >only< has a 24 bit size on some platforms + */ +typedef apr_atomic_t; + +/** + * this function is required on some platforms to initialize the + * atomic operation's internal structures + * @param p pool + * @return APR_SUCCESS on successful completion + */ +apr_status_t apr_atomic_init(apr_pool_t *p); +/** + * read the value stored in a atomic variable + * @param mem the pointer + * @warning on certain platforms this number is not stored + * directly in the pointer. in others it is + */ +apr_uint32_t apr_atomic_read(volatile apr_atomic_t *mem); +/** + * set the value for atomic. + * @param mem the pointer + * @param val the value + */ +void apr_atomic_set(volatile apr_atomic_t *mem, apr_uint32_t val); +/** + * Add 'val' to the atomic variable + * @param mem pointer to the atomic value + * @param val the addition + */ +void apr_atomic_add(volatile apr_atomic_t *mem, apr_uint32_t val); + +/** + * increment the atomic variable by 1 + * @param mem pointer to the atomic value + */ +void apr_atomic_inc(volatile apr_atomic_t *mem); + +/** + * decrement the atomic variable by 1 + * @param mem pointer to the atomic value + * @return zero if the value is zero, otherwise non-zero + */ +int apr_atomic_dec(volatile apr_atomic_t *mem); + +/** + * compare the atomic's value with cmp. + * If they are the same swap the value with 'with' + * @param mem pointer to the atomic value + * @param with what to swap it with + * @param cmp the value to compare it to + * @return the old value of the atomic + * @warning do not mix apr_atomic's with the CAS function. + * on some platforms they may be implemented by different mechanisms + */ +apr_uint32_t apr_atomic_cas(volatile apr_uint32_t *mem, long with, long cmp); + +/** + * compare the pointer's value with cmp. + * If they are the same swap the value with 'with' + * @param mem pointer to the pointer + * @param with what to swap it with + * @param cmp the value to compare it to + * @return the old value of the pointer + */ +void *apr_atomic_casptr(volatile void **mem, void *with, const void *cmp); +#else /* !DOXYGEN */ + +/* The following definitions provide optimized, OS-specific + * implementations of the APR atomic functions on various + * platforms. Any atomic operation that isn't redefined as + * a macro here will be declared as a function later, and + * apr_atomic.c will provide a mutex-based default implementation. + */ + +#if defined(WIN32) + +#define apr_atomic_t LONG + +#define apr_atomic_add(mem, val) InterlockedExchangeAdd(mem,val) +#define apr_atomic_dec(mem) InterlockedDecrement(mem) +#define apr_atomic_inc(mem) InterlockedIncrement(mem) +#define apr_atomic_set(mem, val) InterlockedExchange(mem, val) +#define apr_atomic_read(mem) (*mem) +#define apr_atomic_cas(mem,with,cmp) InterlockedCompareExchange(mem,with,cmp) +#define apr_atomic_init(pool) APR_SUCCESS +#define apr_atomic_casptr(mem,with,cmp) InterlockedCompareExchangePointer(mem,with,cmp) + +#elif defined(NETWARE) + +#define apr_atomic_t unsigned long + +#define apr_atomic_add(mem, val) atomic_add(mem,val) +#define apr_atomic_inc(mem) atomic_inc(mem) +#define apr_atomic_set(mem, val) (*mem = val) +#define apr_atomic_read(mem) (*mem) +#define apr_atomic_init(pool) APR_SUCCESS +#define apr_atomic_cas(mem,with,cmp) atomic_cmpxchg((unsigned long *)(mem),(unsigned long)(cmp),(unsigned long)(with)) + +int apr_atomic_dec(apr_atomic_t *mem); +void *apr_atomic_casptr(void **mem, void *with, const void *cmp); +#define APR_OVERRIDE_ATOMIC_DEC 1 +#define APR_OVERRIDE_ATOMIC_CASPTR 1 + +inline int apr_atomic_dec(apr_atomic_t *mem) +{ + return (atomic_xchgadd(mem, 0xFFFFFFFF) - 1); +} + +inline void *apr_atomic_casptr(void **mem, void *with, const void *cmp) +{ + return (void*)atomic_cmpxchg((unsigned long *)mem,(unsigned long)cmp,(unsigned long)with); +} + +#elif defined(__FreeBSD__) + +#define apr_atomic_t apr_uint32_t +#define apr_atomic_add(mem, val) (atomic_add_int(mem,val),mem) +#define apr_atomic_dec(mem) (atomic_subtract_int(mem,1),mem) +#define apr_atomic_inc(mem) (atomic_add_int(mem,1),mem) +#define apr_atomic_set(mem, val) (atomic_set_int(mem, val),mem) +#define apr_atomic_read(mem) (*mem) + +#elif (defined(__linux__) || defined(__EMX__)) && defined(__i386__) && !APR_FORCE_ATOMIC_GENERIC + +#define apr_atomic_t apr_uint32_t +#define apr_atomic_cas(mem,with,cmp) \ +({ apr_atomic_t prev; \ + asm volatile ("lock; cmpxchgl %1, %2" \ + : "=a" (prev) \ + : "r" (with), "m" (*(mem)), "0"(cmp) \ + : "memory"); \ + prev;}) + +#define apr_atomic_add(mem, val) \ +({ register apr_atomic_t last; \ + do { \ + last = *(mem); \ + } while (apr_atomic_cas((mem), last + (val), last) != last); \ + }) + +#define apr_atomic_dec(mem) \ +({ register apr_atomic_t last; \ + do { \ + last = *(mem); \ + } while (apr_atomic_cas((mem), last - 1, last) != last); \ + (--last != 0); }) + +#define apr_atomic_inc(mem) \ +({ register apr_atomic_t last; \ + do { \ + last = *(mem); \ + } while (apr_atomic_cas((mem), last + 1, last) != last); \ + }) + +#define apr_atomic_set(mem, val) (*(mem) = val) +#define apr_atomic_read(mem) (*(mem)) +#define apr_atomic_init(pool) APR_SUCCESS + +#elif defined(__MVS__) /* OS/390 */ + +#define apr_atomic_t cs_t + +apr_int32_t apr_atomic_add(volatile apr_atomic_t *mem, apr_int32_t val); +apr_uint32_t apr_atomic_cas(volatile apr_atomic_t *mem, apr_uint32_t swap, + apr_uint32_t cmp); +#define APR_OVERRIDE_ATOMIC_ADD 1 +#define APR_OVERRIDE_ATOMIC_CAS 1 + +#define apr_atomic_inc(mem) apr_atomic_add(mem, 1) +#define apr_atomic_dec(mem) apr_atomic_add(mem, -1) +#define apr_atomic_init(pool) APR_SUCCESS + +/* warning: the following two operations, _read and _set, are atomic + * if the memory variables are aligned (the usual case). + * + * If you try really hard and manage to mis-align them, they are not + * guaranteed to be atomic on S/390. But then your program will blow up + * with SIGBUS on a sparc, or with a S0C6 abend if you use the mis-aligned + * variables with other apr_atomic_* operations on OS/390. + */ + +#define apr_atomic_read(p) (*p) +#define apr_atomic_set(mem, val) (*mem = val) + +#endif /* end big if-elseif switch for platform-specifics */ + + +/* Default implementation of the atomic API + * The definitions above may override some or all of the + * atomic functions with optimized, platform-specific versions. + * Any operation that hasn't been overridden as a macro above + * is declared as a function here, unless APR_OVERRIDE_ATOMIC_[OPERATION] + * is defined. (The purpose of the APR_OVERRIDE_ATOMIC_* is + * to allow a platform to declare an apr_atomic_*() function + * with a different signature than the default.) + */ + +#if !defined(apr_atomic_t) +#define apr_atomic_t apr_uint32_t +#endif + +#if !defined(apr_atomic_init) && !defined(APR_OVERRIDE_ATOMIC_INIT) +apr_status_t apr_atomic_init(apr_pool_t *p); +#endif + +#if !defined(apr_atomic_read) && !defined(APR_OVERRIDE_ATOMIC_READ) +#define apr_atomic_read(p) *p +#endif + +#if !defined(apr_atomic_set) && !defined(APR_OVERRIDE_ATOMIC_SET) +void apr_atomic_set(volatile apr_atomic_t *mem, apr_uint32_t val); +#define APR_ATOMIC_NEED_DEFAULT_INIT 1 +#endif + +#if !defined(apr_atomic_add) && !defined(APR_OVERRIDE_ATOMIC_ADD) +void apr_atomic_add(volatile apr_atomic_t *mem, apr_uint32_t val); +#define APR_ATOMIC_NEED_DEFAULT_INIT 1 +#endif + +#if !defined(apr_atomic_inc) && !defined(APR_OVERRIDE_ATOMIC_INC) +void apr_atomic_inc(volatile apr_atomic_t *mem); +#define APR_ATOMIC_NEED_DEFAULT_INIT 1 +#endif + +#if !defined(apr_atomic_dec) && !defined(APR_OVERRIDE_ATOMIC_DEC) +int apr_atomic_dec(volatile apr_atomic_t *mem); +#define APR_ATOMIC_NEED_DEFAULT_INIT 1 +#endif + +#if !defined(apr_atomic_cas) && !defined(APR_OVERRIDE_ATOMIC_CAS) +apr_uint32_t apr_atomic_cas(volatile apr_uint32_t *mem,long with,long cmp); +#define APR_ATOMIC_NEED_DEFAULT_INIT 1 +#endif + +#if !defined(apr_atomic_casptr) && !defined(APR_OVERRIDE_ATOMIC_CASPTR) +#if APR_SIZEOF_VOIDP == 4 +#define apr_atomic_casptr(mem, with, cmp) (void *)apr_atomic_cas((apr_uint32_t *)(mem), (long)(with), (long)cmp) +#else +void *apr_atomic_casptr(volatile void **mem, void *with, const void *cmp); +#define APR_ATOMIC_NEED_DEFAULT_INIT 1 +#endif +#endif + +#ifndef APR_ATOMIC_NEED_DEFAULT_INIT +#define APR_ATOMIC_NEED_DEFAULT_INIT 0 +#endif + +/* If we're using the default versions of any of the atomic functions, + * we'll need the atomic init to set up mutexes. If a platform-specific + * override above has replaced the atomic_init with a macro, it's an error. + */ +#if APR_ATOMIC_NEED_DEFAULT_INIT +#if defined(apr_atomic_init) || defined(APR_OVERRIDE_ATOMIC_INIT) +#error Platform has redefined apr_atomic_init, but other default default atomics require a default apr_atomic_init +#endif +#endif /* APR_ATOMIC_NEED_DEFAULT_INIT */ + +#endif /* !DOXYGEN */ + +/** @} */ + +#ifdef __cplusplus +} +#endif + +#endif /* !APR_ATOMIC_H */ |