atomicbase.h

著名的 helix realplayer 基于手机 symbian 系统的 播放器全套源代码

#define HXAtomicAddRetINT32(p,n)  g_AtomicOps._AddRetINT32((p),(n))
#define HXAtomicSubRetINT32(p,n)  g_AtomicOps._SubRetINT32((p),(n))
#define HXAtomicAddINT32(p,n)     g_AtomicOps._AddRetINT32((p),(n))
#define HXAtomicSubINT32(p,n)     g_AtomicOps._SubRetINT32((p),(n))

#define HXAtomicIncUINT32(p)      g_AtomicOps._AddRetUINT32((p),(UINT32)1)
#define HXAtomicDecUINT32(p)      g_AtomicOps._SubRetUINT32((p),(UINT32)1)
#define HXAtomicIncRetUINT32(p)   g_AtomicOps._AddRetUINT32((p),(UINT32)1)
#define HXAtomicDecRetUINT32(p)   g_AtomicOps._SubRetUINT32((p),(UINT32)1)

#define HXAtomicAddRetUINT32(p,n) g_AtomicOps._AddRetUINT32((p),(n))
#define HXAtomicSubRetUINT32(p,n) g_AtomicOps._SubRetUINT32((p),(n))
#define HXAtomicAddUINT32(p,n)    g_AtomicOps._AddRetUINT32((p),(n))
#define HXAtomicSubUINT32(p,n)    g_AtomicOps._SubRetUINT32((p),(n))



/***********************************************************************
 * SYMBIAN
 *
 * Implementation Notes:
 *
 * Note: This is an imcompletely-defined platform, be aware that
 * not all standard HXAtomic operators are defined!
 *
 */
#elif defined(_SYMBIAN)

/* Increment by 1 and return new value */
inline INT32
HXAtomicIncRetINT32(INT32* pNum)
{
    return User::LockedInc(*((TInt*)pNum)) + 1;
}

/* Decrement by 1 and return new value */
inline INT32
HXAtomicDecRetINT32(INT32* pNum)
{
    return User::LockedDec(*((TInt*)pNum)) - 1;
}

/* Increment by 1 and return new value */
inline UINT32
HXAtomicIncRetUINT32(UINT32* pNum)
{
    return ((UINT32)User::LockedInc(*((TInt*)pNum))) + 1;
}

/* Decrement by 1 and return new value */
inline UINT32
HXAtomicDecRetUINT32(UINT32* pNum)
{
    return ((UINT32)User::LockedDec(*((TInt*)pNum))) - 1;
}

#define HXAtomicIncINT32(p)    HXAtomicIncRetINT32((p))
#define HXAtomicDecINT32(p)    HXAtomicDecRetINT32((p))
#define HXAtomicIncUINT32(p)   HXAtomicIncRetUINT32((p))
#define HXAtomicDecUINT32(p)   HXAtomicDecRetUINT32((p))

#if 0

/* 
 * Add and subtract operations are not implemented
 * at this time because there isn't an easy way to
 * do it using the facilities provided by Symbian.
 * Assembly will likely be needed.
 */

/* Add n and return new value */
inline INT32
HXAtomicAddRetINT32(INT32* pNum, INT32 n)
{

}

/* Subtract n and return new value */
inline INT32
HXAtomicSubRetINT32(INT32* pNum, INT32 n)
{

}

/* Add n and return new value */
inline UINT32
HXAtomicAddRetUINT32(UINT32* pNum, UINT32 n)
{

}

/* Subtract n and return new value */
inline UINT32
HXAtomicSubRetUINT32(UINT32* pNum, UINT32 n)
{

}

#define HXAtomicAddINT32(p,n)  HXAtomicAddRetINT32((p),(n))
#define HXAtomicSubINT32(p,n)  HXAtomicSubRetINT32((p),(n))

#define HXAtomicAddUINT32(p,n) HXAtomicAddRetUINT32((p),(n))
#define HXAtomicSubUINT32(p,n) HXAtomicSubRetUINT32((p),(n))

#endif

/***********************************************************************
 * Linux / ARM (gcc)
 *
 * Implementation Notes:
 *
 * This implementation sacrifices being able to store the value
 * 0x800000000 in the INT32 value, which is a special "busy" marker value.
 * Since these are intended for use primarily with AddRef/Release and
 * resource usage counters, this should be acceptable for now.  If a counter
 * is incremented to the point it would conflict with the flag, it is
 * incremented one more to hop over it.  The same in reverse for decrement.
 *
 * Basic design of the flag-based implementation:
 *   1. Load a register with 0x80000000
 *   2. _atomically_ swap it with the INT32 (critical!)
 *   3. Compare what we got with 0x80000000
 *   4. Branch if equal to #2
 *   5. Increment (or decrement) the result
 *   6. Compare to 0x80000000
 *   7. Increment (or decrement) again if equal
 *   8. Save the new value to the INT32's location in memory
 *   9. Return new INT32 result if required
 *   
 */
#elif defined (_ARM) && defined (__GNUC__)

/* Increment by 1 */
inline void
HXAtomicIncUINT32(UINT32* pNum)
{
    UINT32 ulTmp;
    __asm__ __volatile__(
"        mov   %0, #0x80000000;\n"      /* Set ulTmp to 0x800000000    */
"1:      swp   %0, %0, [%1];\n"         /* Swap *pNum and ulTmp        */
"        cmp   %0, #0x80000000;\n"      /* Is someone else using pNum? */
"        beq   1;\n"                    /* If so, retry...             */
"        add   %0, %0, #1;\n"           /* Increment ulTmp             */
"        cmp   %0, #0x80000000;\n"      /* check for overflow          */
"        addeq %0, %0, #1;\n"           /* if so, increment again      */
"        str   %0, [%1];\n"             /* Save new value into *pNum   */
        : /* no output */
        : "r" (ulTmp), "r" (pNum)
        : "cc", "memory"
        );
}

/* Decrement by 1 */
inline void
HXAtomicDecUINT32(UINT32* pNum)
{
    UINT32 ulTmp;
    __asm__ __volatile__(
"        mov   %0, #0x80000000;\n"      /* Set ulTmp to 0x800000000    */
"1:      swp   %0, %0, [%1];\n"         /* Swap *pNum and ulTmp        */
"        cmp   %0, #0x80000000;\n"      /* Is someone else using pNum? */
"        beq   1;\n"                    /* If so, retry...             */
"        sub   %0, %0, #1;\n"           /* Decrement ulTmp             */
"        cmp   %0, #0x80000000;\n"      /* check for overflow          */
"        subeq %0, %0, #1;\n"           /* if so, decrement again      */
"        str   %0, [%1];\n"             /* Save new value into *pNum   */
        : /* no output */
        :  "r" (ulTmp), "r" (pNum)
        : "cc", "memory"
        );
}

/* Increment by 1 and return new value */
inline UINT32
HXAtomicIncRetUINT32(UINT32* pNum)
{
    volatile UINT32 ulRet;
    __asm__ __volatile__(
"        mov   %0, #0x80000000;\n"      /* Set ulRet to 0x80000000     */
"1:      swp   %0, %0, [%1];\n"         /* Swap *pNum and ulRet        */
"        cmp   %0, #0x80000000;\n"      /* Is someone else using pNum? */
"        beq   1;\n"                    /* If so, retry...             */
"        add   %0, %0, #1;\n"           /* Increment ulRet             */
"        cmp   %0, #0x80000000;\n"      /* check for overflow          */
"        addeq %0, %0, #1;\n"         /* if so, increment again      */
"        str   %0, [%1];\n"             /* Save new value into *pNum   */
        : "=&r" (ulRet)
        : "r" (pNum)
        : "cc", "memory"
        );
    return ulRet;
}

/* Decrement by 1 and return new value */
inline UINT32
HXAtomicDecRetUINT32(UINT32* pNum)
{
    volatile UINT32 ulRet;
    __asm__ __volatile__(
"        mov   %0, #0x80000000;\n"      /* Set ulRet to 0x80000000     */
"1:      swp   %0, %0, [%1];\n"         /* Swap *pNum and ulRet        */
"        cmp   %0, #0x80000000;\n"      /* Is someone else using pNum? */
"        beq   1;\n"                    /* If so, retry...             */
"        sub   %0, %0, #1;\n"           /* Decrement ulRet             */
"        cmp   %0, #0x80000000;\n"      /* check for overflow          */
"        subeq %0, %0, #1;\n"         /* if so, decrement again      */
"        str   %0, [%1];\n"             /* Save new value into *pNum   */
        : "=&r" (ulRet)
        : "r" (pNum)
        : "cc", "memory"
        );
    return ulRet;
}

/* Add n */
inline void
HXAtomicAddUINT32(UINT32* pNum, UINT32 ulNum)
{
    UINT32 ulTmp;
    __asm__ __volatile__(
"        mov   %0, #0x80000000;\n"      /* Set ulTmp to 0x800000000    */
"1:      swp   %0, %0, [%1];\n"         /* Swap *pNum and ulTmp        */
"        cmp   %0, #0x80000000;\n"      /* Is someone else using pNum? */
"        beq   1;\n"                    /* If so, retry...             */
"        add   %0, %0, %2;\n"           /* Add ulNum to ulTmp          */
"        cmp   %0, #0x80000000;\n"      /* check for overflow          */
"        addeq %0, %0, #1;\n"           /* if so, increment again      */
"        str   %0, [%1];\n"             /* Save new value into *pNum   */
        : /* no output */
        : "r" (ulTmp), "r" (pNum), "r" (ulNum)
        : "cc", "memory"
        );
}

/* Subtract n */
inline void
HXAtomicSubUINT32(UINT32* pNum, UINT32 ulNum)
{
    UINT32 ulTmp;
    __asm__ __volatile__(
"        mov   %0, #0x80000000;\n"      /* Set ulTmp to 0x800000000    */
"1:      swp   %0, %0, [%1];\n"         /* Swap *pNum and ulTmp        */
"        cmp   %0, #0x80000000;\n"      /* Is someone else using pNum? */
"        beq   1;\n"                    /* If so, retry...             */
"        sub   %0, %0, %2;\n"           /* Subtract ulNum from ulTmp   */
"        cmp   %0, #0x80000000;\n"      /* check for overflow          */
"        subeq %0, %0, #1;\n"           /* if so, decrement again      */
"        str   %0, [%1];\n"             /* Save new value into *pNum   */
        : /* no output */
        : "r" (ulTmp), "r" (pNum), "r" (ulNum)
        : "cc", "memory"
        );
}

/* Add n and return new value */
inline UINT32
HXAtomicAddRetUINT32(UINT32* pNum, UINT32 ulNum)
{
    volatile UINT32 ulRet;
    __asm__ __volatile__(
"        mov   %0, #0x80000000;\n"      /* Set ulRet to 0x80000000     */
"1:      swp   %0, %0, [%1];\n"         /* Swap *pNum and ulRet        */
"        cmp   %0, #0x80000000;\n"      /* Is someone else using pNum? */
"        beq   1;\n"                    /* If so, retry...             */
"        add   %0, %0, %2;\n"           /* Add ulNum to ulRet          */
"        cmp   %0, #0x80000000;\n"      /* check for overflow          */
"        addeq %0, %0, #1;\n"         /* if so, increment again      */
"        str   %0, [%1];\n"             /* Save new value into *pNum   */
        : "=&r" (ulRet)
        : "r" (pNum) , "r" (ulNum)
        : "cc", "memory"
        );
    return ulRet;
}

/* Subtract n and return new value */
inline UINT32
HXAtomicSubRetUINT32(UINT32* pNum, UINT32 ulNum)
{   
    volatile UINT32 ulRet;
    __asm__ __volatile__(
"        mov   %0, #0x80000000;\n"      /* Set ulRet to 0x80000000     */
"1:      swp   %0, %0, [%1];\n"         /* Swap *pNum and ulRet        */
"        cmp   %0, #0x80000000;\n"      /* Is someone else using pNum? */
"        beq   1;\n"                    /* If so, retry...             */
"        sub   %0, %0, %2;\n"           /* Subtract ulNum from ulRet   */
"        cmp   %0, #0x80000000;\n"      /* check for overflow          */
"        subeq %0, %0, #1;\n"         /* if so, decrement again      */
"        str   %0, [%1];\n"             /* Save new value into *pNum   */
        : "=&r" (ulRet)
        : "r" (pNum), "r" (ulNum)
        : "cc", "memory"
        );
    return ulRet;
}

inline void HXAtomicIncINT32(INT32* p)              { HXAtomicIncUINT32((UINT32*)p); }
inline void HXAtomicDecINT32(INT32* p)              { HXAtomicDecUINT32((UINT32*)p); }
inline void HXAtomicAddINT32(INT32* p, INT32 n)     { HXAtomicAddUINT32((UINT32*)p, (UINT32)n); }
inline void HXAtomicSubINT32(INT32* p, INT32 n)     { HXAtomicSubUINT32((UINT32*)p, (UINT32)n); }
inline INT32 HXAtomicIncRetINT32(INT32* p)          { return HXAtomicIncRetUINT32((UINT32*)p); }
inline INT32 HXAtomicDecRetINT32(INT32* p)          { return HXAtomicDecRetUINT32((UINT32*)p); }
inline INT32 HXAtomicAddRetINT32(INT32* p, INT32 n) { return HXAtomicAddRetUINT32((UINT32*)p, (UINT32)n); }
inline INT32 HXAtomicSubRetINT32(INT32* p, INT32 n) { return HXAtomicSubRetUINT32((UINT32*)p, (UINT32)n); }

/***********************************************************************
 * Add new platforms above here
 */
#else

//
// Unsupported platform
//

#  ifndef HELIX_CONFIG_DISABLE_ATOMIC_OPERATORS
// Defining HELIX_CONFIG_DISABLE_ATOMIC_OPERATORS will use the ++ and --
// operators in place of atomic operators in some places in the code. These
// operators are not thread-safe, and should only be used in the intermediary
// stages of porting.
#    error "You need to create atomic dec/inc opers for your platform or #define HELIX_CONFIG_DISABLE_ATOMIC_OPERATORS"
#  endif
#endif



/*************************************************************************/

/*
 * Conditional override of InterlockedIncrement/Decrement
 *
 * Place this in your Umakefil/.pcf file to turn off atomic
 * InterlockedIncrement/Decrement on a per-module basis,
 * or place it in your umake profile for system-wide scope.
 * If this is defined you'll still have access to the underlying
 * HXAtomicxxx operators (if they exist for your platform),
 * just that the specific InterlockedIncrement/InterlockedDecrement
 * macros won't be defined to use them.
 */
#if !defined (HELIX_CONFIG_DISABLE_ATOMIC_OPERATORS)

#undef InterlockedIncrement
#undef InterlockedDecrement

// Since many classes (incorrectly) implement their refcount using LONG32
// rather than the proper ULONG32, we have to use the typecast for things
// to build on many platforms.
#define InterlockedIncrement(p) HXAtomicIncRetUINT32((UINT32*)(p))
#define InterlockedDecrement(p) HXAtomicDecRetUINT32((UINT32*)(p))

#define HAVE_INTERLOCKED_INCREMENT //so hxcom.h doesn't redefine these to ++/--

#endif /* !defined(HELIX_CONFIG_DISABLE_ATOMIC_OPERATORS) */

#endif /* _ATOMICBASE_H_ */