diff options
Diffstat (limited to 'winsup/cygwin/exception.h')
-rw-r--r-- | winsup/cygwin/exception.h | 84 |
1 files changed, 34 insertions, 50 deletions
diff --git a/winsup/cygwin/exception.h b/winsup/cygwin/exception.h index 83cb21fcf..9e34799fe 100644 --- a/winsup/cygwin/exception.h +++ b/winsup/cygwin/exception.h @@ -94,8 +94,10 @@ to install your own exception filter. This one is documented. a teensy bit of detail of the innards of exception handling (i.e. what we have to do). */ -typedef int (exception_handler) (EXCEPTION_RECORD *, struct _exception_list *, - CONTEXT *, void *); +typedef EXCEPTION_DISPOSITION (exception_handler) (EXCEPTION_RECORD *, + struct _exception_list *, + CONTEXT *, + void *); typedef struct _exception_list { @@ -104,70 +106,53 @@ typedef struct _exception_list } exception_list; extern exception_list *_except_list asm ("%fs:0"); -#else -typedef void exception_list; -#endif /* !__x86_64 */ +typedef void *PDISPATCHER_CONTEXT; class exception { -#ifdef __x86_64__ - static LONG myfault_handle (LPEXCEPTION_POINTERS ep); -#else exception_list el; exception_list *save; -#endif /* __x86_64__ */ - static int handle (EXCEPTION_RECORD *, exception_list *, CONTEXT *, void *); + static EXCEPTION_DISPOSITION handle (EXCEPTION_RECORD *, exception_list *, + CONTEXT *, PDISPATCHER_CONTEXT); public: exception () __attribute__ ((always_inline)) { /* Install SEH handler. */ + save = _except_list; + el.handler = handle; + el.prev = _except_list; + _except_list = ⪙ + }; + ~exception () __attribute__ ((always_inline)) { _except_list = save; } +}; + +#else + +#define exception_list void +typedef struct _DISPATCHER_CONTEXT *PDISPATCHER_CONTEXT; + +class exception +{ #ifdef __x86_64__ + static EXCEPTION_DISPOSITION myfault (EXCEPTION_RECORD *, exception_list *, + CONTEXT *, PDISPATCHER_CONTEXT); +#endif + static EXCEPTION_DISPOSITION handle (EXCEPTION_RECORD *, exception_list *, + CONTEXT *, PDISPATCHER_CONTEXT); +public: + exception () __attribute__ ((always_inline)) + { + /* Install SEH handler. */ asm volatile ("\n\ 1: \n\ .seh_handler \ - _ZN9exception6handleEP17_EXCEPTION_RECORDPvP8_CONTEXTS2_, \ + _ZN9exception6handleEP17_EXCEPTION_RECORDPvP8_CONTEXTP19_DISPATCHER_CONTEXT, \ @except \n\ .seh_handlerdata \n\ .long 1 \n\ .rva 1b, 2f, 2f, 2f \n\ .seh_code \n"); -#else - save = _except_list; - el.handler = handle; - el.prev = _except_list; - _except_list = ⪙ -#endif /* __x86_64__ */ }; -#ifdef __x86_64__ - static void install_myfault_handler () __attribute__ ((always_inline)) - { - /* Install myfault exception handler as VEH. Here's what happens: - Some Windows DLLs (advapi32, for instance) are using SEH to catch - exceptions inside its own functions. If we install a VEH handler - to catch all exceptions, our Cygwin VEH handler would illegitimatly - handle exceptions inside of Windows DLLs which are usually handled - by its own SEH handler. So, for standard exceptions we use an SEH - handler as installed in the constructor above so as not to override - the SEH handlers in Windows DLLs. - But we have a special case, myfault handling. The myfault handling - catches exceptions inside of the Cygwin DLL, some of them entirely - expected as in verifyable_object_isvalid. The ultimately right thing - to do would be to install SEH handlers for each of these cases. - But there are two problems with that: - - 1. It would be a massive and, partially unreliable change in the - calling functions due to the incomplete SEH support in GCC. - - 2. It doesn't always work. Certain DLLs appear to call Cygwin - functions during DLL initialization while the SEH handler is - not installed in the active call frame. For these cases we - need a more generic approach. - - So, what we do here is to install a myfault VEH handler. This - function is called from dll_crt0_0, so the myfault handler is - available very early. */ - AddVectoredExceptionHandler (1, myfault_handle); - } ~exception () __attribute__ ((always_inline)) { asm volatile ("\n\ @@ -175,11 +160,10 @@ public: 2: \n\ nop \n"); } -#else - ~exception () __attribute__ ((always_inline)) { _except_list = save; } -#endif /* !__x86_64__ */ }; +#endif /* !__x86_64 */ + class cygwin_exception { PUINT_PTR framep; |