diff --git a/Parser/myreadline.c b/Parser/myreadline.c index cb1cf0f56d7..d864623f1a2 100644 --- a/Parser/myreadline.c +++ b/Parser/myreadline.c @@ -35,6 +35,9 @@ int (*PyOS_InputHook)(void) = NULL; static int my_fgets(char *buf, int len, FILE *fp) { +#ifdef MS_WINDOWS + HANDLE hInterruptEvent; +#endif char *p; int err; while (1) { @@ -50,32 +53,28 @@ my_fgets(char *buf, int len, FILE *fp) return 0; /* No error */ err = errno; #ifdef MS_WINDOWS - /* In the case of a Ctrl+C or some other external event - interrupting the operation: - Win2k/NT: ERROR_OPERATION_ABORTED is the most recent Win32 - error code (and feof() returns TRUE). - Win9x: Ctrl+C seems to have no effect on fgets() returning - early - the signal handler is called, but the fgets() - only returns "normally" (ie, when Enter hit or feof()) + /* Ctrl-C anywhere on the line or Ctrl-Z if the only character + on a line will set ERROR_OPERATION_ABORTED. Under normal + circumstances Ctrl-C will also have caused the SIGINT handler + to fire which will have set the event object returned by + _PyOS_SigintEvent. This signal fires in another thread and + is not guaranteed to have occurred before this point in the + code. + + Therefore: check whether the event is set with a small timeout. + If it is, assume this is a Ctrl-C and reset the event. If it + isn't set assume that this is a Ctrl-Z on its own and drop + through to check for EOF. */ if (GetLastError()==ERROR_OPERATION_ABORTED) { - /* Signals come asynchronously, so we sleep a brief - moment before checking if the handler has been - triggered (we cant just return 1 before the - signal handler has been called, as the later - signal may be treated as a separate interrupt). - */ - Sleep(1); - if (PyOS_InterruptOccurred()) { + hInterruptEvent = _PyOS_SigintEvent(); + switch (WaitForSingleObject(hInterruptEvent, 10)) { + case WAIT_OBJECT_0: + ResetEvent(hInterruptEvent); return 1; /* Interrupt */ + case WAIT_FAILED: + return -2; /* Error */ } - /* Either the sleep wasn't long enough (need a - short loop retrying?) or not interrupted at all - (in which case we should revisit the whole thing!) - Logging some warning would be nice. assert is not - viable as under the debugger, the various dialogs - mean the condition is not true. - */ } #endif /* MS_WINDOWS */ if (feof(fp)) { @@ -94,7 +93,7 @@ my_fgets(char *buf, int len, FILE *fp) #endif if (s < 0) return 1; - /* try again */ + /* try again */ continue; } #endif