value.h

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/* @file value.h
   concurrency helpers Atomic<T> and DiagStr
*/

#pragma once

namespace mongo {

    extern mutex _atomicMutex;

    template<typename T>
    class Atomic : boost::noncopyable {
        T val;
    public:
        Atomic<T>() { }

        void operator=(const T& a) {
            scoped_lock lk(_atomicMutex);
            val = a;
        }

        operator T() const {
            scoped_lock lk(_atomicMutex);
            return val;
        }

        class tran : private scoped_lock {
            Atomic<T>& _a;
        public:
            tran(Atomic<T>& a) : scoped_lock(_atomicMutex), _a(a) { }
            T& ref() { return _a.val; }
        };
    };

    class DiagStr {
        char buf1[256];
        char buf2[256];
        char *p;
    public:
        DiagStr() {
            memset(buf1, 0, 256);
            memset(buf2, 0, 256);
            p = buf1;
        }

        const char * get() const { return p; }

        void set(const char *s) {
            char *q = (p==buf1) ? buf2 : buf1;
            strncpy(q, s, 255);
            p = q;
        }
    };

}

---

mongodb
Author(s): Nate Koenig
autogenerated on Fri Jan 11 12:15:19 2013