Files
mongo/db/globals.h
Dwight 3844dd29f8 concurrency
beginnings of a bit of framework to help with correctness. tbd if helpful will iterate.
2011-10-26 15:27:19 -04:00

55 lines
1.3 KiB
C++

// @file globals.h
// grouping of global variables to make concurrency work clearer
#pragma once
namespace mongo {
void assertStartingUp();
// this is prototype for now, we'll see if it is helpful
/** "value is Const After Server Init" helper
*
* Example:
*
* casi<int> foo = 3;
* foo.ref() = 4; // asserts if not still in server init
* int x = foo+1; // ok anytime
*
*/
template< class T >
class casi : boost::noncopyable {
T val;
public:
casi(const T& t) : val(t) {
DEV assertStartingUp();
}
operator const T& () { return val; }
T& ref() {
DEV assertStartingUp();
return val;
}
};
/** partially specialized for cases where out global variable is a pointer -- we want the value
* pointed at to be constant, not just the pointer itself
*/
template< typename T >
class casi<T*> : boost::noncopyable {
T * val;
void operator=(T*);
public:
casi(T* t) : val(t) {
DEV assertStartingUp();
}
operator const T* () { return val; }
const T* get() { return val; }
T*& ref() {
DEV assertStartingUp();
return val;
}
};
}