forked from 0ad/0ad
janwas
cc243f67eb
- fix lots of 64-bit warnings - round_up/down now templates - avoid warning with definition of byte swap functions; remove duplication of that in wsdl - codec_zlib.cpp: avoid domination warning - vfs/file_cache: VFS is now responsible for handling zero-length files (no longer considered an error; just returns zero pointer and size=0) - cpu: export all functions (thus obviating cpu_memcpy_thunk). this required renaming asm functions and adding thunk functions that call them - winit: fix segment merge statement, reinstate /include (otherwise init functions are stripped by linker) - wstartup: VC CRT init section definitions have changed in amd64 build; match their definition - wsysdep.cpp: more descriptive text for osError = 0 This was SVN commit r5899.
75 lines
2.2 KiB
C++
75 lines
2.2 KiB
C++
/**
|
|
* =========================================================================
|
|
* File : module_init.cpp
|
|
* Project : 0 A.D.
|
|
* Description : helpers for module initialization/shutdown.
|
|
* =========================================================================
|
|
*/
|
|
|
|
// license: GPL; see lib/license.txt
|
|
|
|
#include "precompiled.h"
|
|
#include "module_init.h"
|
|
|
|
#include "lib/sysdep/cpu.h" // cpu_CAS, cpu_AtomicAdd
|
|
|
|
// notes:
|
|
// - value must be 0 to allow users to just define uninitialized static
|
|
// variables (they don't have access to our MODULE_* symbols)
|
|
// - unlike expected in-game operation, the self-tests require repeated
|
|
// sequences of init/shutdown pairs. we therefore allow this in general
|
|
// (resetting back to MODULE_UNINITIALIZED after shutdown) because
|
|
// there's no real disadvantage other than loss of strictness.
|
|
static const ModuleInitState MODULE_UNINITIALIZED = 0u;
|
|
|
|
// (1..N = reference count)
|
|
|
|
static const ModuleInitState MODULE_ERROR = ~(uintptr_t)1u;
|
|
|
|
|
|
bool ModuleShouldInitialize(volatile ModuleInitState* pInitState)
|
|
{
|
|
// currently uninitialized, so give the green light.
|
|
if(cpu_CAS(pInitState, MODULE_UNINITIALIZED, 1))
|
|
return true;
|
|
|
|
// increment reference count - unless already in a final state.
|
|
retry:
|
|
ModuleInitState latchedInitState = *pInitState;
|
|
if(latchedInitState == MODULE_ERROR)
|
|
return false;
|
|
if(!cpu_CAS(pInitState, latchedInitState, latchedInitState+1))
|
|
goto retry;
|
|
return false;
|
|
}
|
|
|
|
|
|
bool ModuleShouldShutdown(volatile ModuleInitState* pInitState)
|
|
{
|
|
// decrement reference count - unless already in a final state.
|
|
retry:
|
|
ModuleInitState latchedInitState = *pInitState;
|
|
if(latchedInitState == MODULE_UNINITIALIZED || latchedInitState == MODULE_ERROR)
|
|
return false;
|
|
if(!cpu_CAS(pInitState, latchedInitState, latchedInitState-1))
|
|
goto retry;
|
|
|
|
// refcount reached zero => allow shutdown.
|
|
if(latchedInitState-1 == MODULE_UNINITIALIZED)
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
|
|
void ModuleSetError(volatile ModuleInitState* pInitState)
|
|
{
|
|
*pInitState = MODULE_ERROR;
|
|
}
|
|
|
|
|
|
bool ModuleIsError(volatile ModuleInitState* pInitState)
|
|
{
|
|
return (*pInitState == MODULE_ERROR);
|
|
}
|