You are viewing a plain text version of this content. The canonical link for it is here.
Posted to commits@apr.apache.org by iv...@apache.org on 2024/03/12 14:21:41 UTC
svn commit: r1916257 - in /apr/apr/branches/1.7.x-r1871447: include/arch/win32/apr_arch_misc.h misc/win32/misc.c
Author: ivan
Date: Tue Mar 12 14:21:40 2024
New Revision: 1916257
URL: http://svn.apache.org/viewvc?rev=1916257&view=rev
Log:
On 1.7.x-r1871447 branch:
Merge r1871447 from trunk.
Modified:
apr/apr/branches/1.7.x-r1871447/include/arch/win32/apr_arch_misc.h
apr/apr/branches/1.7.x-r1871447/misc/win32/misc.c
Modified: apr/apr/branches/1.7.x-r1871447/include/arch/win32/apr_arch_misc.h
URL: http://svn.apache.org/viewvc/apr/apr/branches/1.7.x-r1871447/include/arch/win32/apr_arch_misc.h?rev=1916257&r1=1916256&r2=1916257&view=diff
==============================================================================
--- apr/apr/branches/1.7.x-r1871447/include/arch/win32/apr_arch_misc.h (original)
+++ apr/apr/branches/1.7.x-r1871447/include/arch/win32/apr_arch_misc.h Tue Mar 12 14:21:40 2024
@@ -198,20 +198,15 @@ FARPROC apr_load_dll_func(apr_dlltoken_e
*/
#define APR_DECLARE_LATE_DLL_FUNC(lib, rettype, calltype, fn, ord, args, names) \
typedef rettype (calltype *apr_winapi_fpt_##fn) args; \
- static apr_winapi_fpt_##fn apr_winapi_pfn_##fn = NULL; \
- static INIT_ONCE apr_winapi_ctrl_##fn = {INIT_ONCE_STATIC_INIT}; \
- static BOOL WINAPI apr_winapi_init_once_##fn(PINIT_ONCE init_once,\
- PVOID baton, PVOID *context) \
- { \
- apr_winapi_pfn_##fn = (apr_winapi_fpt_##fn) \
- apr_load_dll_func(lib, #fn, ord); \
- return TRUE; \
- } \
-static APR_INLINE int apr_winapi_ld_##fn(void) \
- { if (apr_winapi_pfn_##fn) return 1; \
- InitOnceExecuteOnce(&apr_winapi_ctrl_##fn, apr_winapi_init_once_##fn, \
- NULL, NULL); \
- if (apr_winapi_pfn_##fn) return 1; else return 0; }; \
+ static volatile apr_winapi_fpt_##fn apr_winapi_pfn_##fn = (PVOID) (ULONG_PTR) (-1); \
+ static APR_INLINE int apr_winapi_ld_##fn(void) \
+ { \
+ apr_winapi_fpt_##fn cached_func = apr_winapi_pfn_##fn; \
+ if (cached_func == (PVOID) (ULONG_PTR) (-1)) { \
+ cached_func = (apr_winapi_fpt_##fn) apr_load_dll_func(lib, #fn, ord); \
+ InterlockedExchangePointer(&((PVOID)apr_winapi_pfn_##fn), cached_func); \
+ } \
+ if (cached_func) return 1; else return 0; }; \
static APR_INLINE rettype apr_winapi_##fn args \
{ if (apr_winapi_ld_##fn()) \
return (*(apr_winapi_pfn_##fn)) names; \
Modified: apr/apr/branches/1.7.x-r1871447/misc/win32/misc.c
URL: http://svn.apache.org/viewvc/apr/apr/branches/1.7.x-r1871447/misc/win32/misc.c?rev=1916257&r1=1916256&r2=1916257&view=diff
==============================================================================
--- apr/apr/branches/1.7.x-r1871447/misc/win32/misc.c (original)
+++ apr/apr/branches/1.7.x-r1871447/misc/win32/misc.c Tue Mar 12 14:21:40 2024
@@ -162,52 +162,60 @@ apr_status_t apr_get_oslevel(apr_oslevel
*/
typedef struct win32_late_dll_t {
- INIT_ONCE control;
const char *dll_name;
- HMODULE dll_handle;
+ volatile HMODULE dll_handle;
} win32_late_dll_t;
static win32_late_dll_t late_dll[DLL_defined] = {
- {INIT_ONCE_STATIC_INIT, "kernel32", NULL},
- {INIT_ONCE_STATIC_INIT, "advapi32", NULL},
- {INIT_ONCE_STATIC_INIT, "mswsock", NULL},
- {INIT_ONCE_STATIC_INIT, "ws2_32", NULL},
- {INIT_ONCE_STATIC_INIT, "shell32", NULL},
- {INIT_ONCE_STATIC_INIT, "ntdll.dll", NULL},
- {INIT_ONCE_STATIC_INIT, "Iphplapi", NULL}
+ {"kernel32", INVALID_HANDLE_VALUE},
+ {"advapi32", INVALID_HANDLE_VALUE},
+ {"mswsock", INVALID_HANDLE_VALUE},
+ {"ws2_32", INVALID_HANDLE_VALUE},
+ {"shell32", INVALID_HANDLE_VALUE},
+ {"ntdll.dll", INVALID_HANDLE_VALUE},
+ {"Iphplapi", INVALID_HANDLE_VALUE}
};
-static BOOL WINAPI load_dll_callback(PINIT_ONCE InitOnce,
- PVOID Parameter,
- PVOID *Context)
-{
- win32_late_dll_t *dll = Parameter;
-
- dll->dll_handle = LoadLibrary(dll->dll_name);
-
- return TRUE;
-}
-
FARPROC apr_load_dll_func(apr_dlltoken_e fnLib, char* fnName, int ordinal)
{
win32_late_dll_t *dll = &late_dll[fnLib];
+ HMODULE cached_dll_handle;
+
+ /* Pointer sized reads are atomic on Windows. */
+ cached_dll_handle = dll->dll_handle;
+ if (cached_dll_handle == INVALID_HANDLE_VALUE) {
+ HMODULE dll_handle = NULL;
+
+ dll_handle = LoadLibrary(dll->dll_name);
+
+ cached_dll_handle = InterlockedCompareExchangePointer(&dll->dll_handle,
+ dll_handle,
+ INVALID_HANDLE_VALUE);
+ if (cached_dll_handle == INVALID_HANDLE_VALUE) {
+ cached_dll_handle = dll_handle;
+ }
+ else if (dll_handle) {
+ /* Other thread won the race: release our library handle. */
+ FreeLibrary(dll_handle);
+ }
+ }
- InitOnceExecuteOnce(&dll->control, load_dll_callback, dll, NULL);
- if (!dll->dll_handle)
+ if (!cached_dll_handle) {
return NULL;
+ }
#if defined(_WIN32_WCE)
if (ordinal)
- return GetProcAddressA(dll->dll_handle,
+ return GetProcAddressA(cached_dll_handle,
(const char *) (apr_ssize_t)ordinal);
else
- return GetProcAddressA(dll->dll_handle, fnName);
+ return GetProcAddressA(cached_dll_handle, fnName);
#else
if (ordinal)
- return GetProcAddress(dll->dll_handle,
+ return GetProcAddress(cached_dll_handle,
(const char *) (apr_ssize_t)ordinal);
else
- return GetProcAddress(dll->dll_handle, fnName);
+ return GetProcAddress(cached_dll_handle, fnName);
#endif
}