From 6dcfcb8be9f31859901af2772441a1ad224c9190 Mon Sep 17 00:00:00 2001 From: dgp Date: Wed, 28 Aug 2013 18:05:07 +0000 Subject: Rework the re-resolution after enter traces machinery with cleaner separations and neater interfaces. --- generic/tclBasic.c | 214 +++++++++++++++++------------------------------------ 1 file changed, 69 insertions(+), 145 deletions(-) diff --git a/generic/tclBasic.c b/generic/tclBasic.c index af747cd..bafb4c2 100644 --- a/generic/tclBasic.c +++ b/generic/tclBasic.c @@ -147,8 +147,7 @@ static int TEOV_NotFound(Tcl_Interp *interp, int objc, Tcl_Obj *const objv[], Namespace *lookupNsPtr); static int TEOV_RunEnterTraces(Tcl_Interp *interp, Command **cmdPtrPtr, Tcl_Obj *commandPtr, int objc, - Tcl_Obj *const objv[], Namespace *lookupNsPtr, - int weLookUp); + Tcl_Obj *const objv[]); static Tcl_NRPostProc RewindCoroutineCallback; static Tcl_NRPostProc TailcallCleanup; static Tcl_NRPostProc TEOEx_ByteCodeCallback; @@ -4126,6 +4125,7 @@ EvalObjvCore( int objc = PTR2INT(data[2]); Tcl_Obj **objv = data[3]; Interp *iPtr = (Interp *) interp; + int enterTracesDone = 0; /* * Capture the namespace we should do command name resolution in, as @@ -4152,137 +4152,100 @@ EvalObjvCore( /* * Push records for task to be done on return, in INVERSE order. First, if * needed, the exception handlers (as they should happen last). + * TODO: Consider moving this up. */ if (!(flags & TCL_EVAL_NOERR)) { TEOV_PushExceptionHandlers(interp, objc, objv, flags); } - if (preCmdPtr) { - cmdPtr = preCmdPtr; - } else { + /* + * Configure evaluation context to match the requested flags. + */ + if (lookupNsPtr) { /* - * Configure evaluation context to match the requested flags. + * Do nothing. Caller gave us the lookup namespace. Use it. + * Overrides TCL_EVAL_GLOBAL. For both lookup and eval. + * TODO: Is that a bug? */ + } else if (flags & TCL_EVAL_INVOKE) { + lookupNsPtr = iPtr->globalNsPtr; + } else { - if (lookupNsPtr) { - /* - * Do nothing. Caller gave us the lookup namespace. Use it. - * Overrides TCL_EVAL_GLOBAL. For both lookup and eval. - */ - } else if (flags & TCL_EVAL_INVOKE) { - lookupNsPtr = iPtr->globalNsPtr; - } else { - - /* - * TCL_EVAL_INVOKE was not set: clear rewrite rules - */ + /* + * TCL_EVAL_INVOKE was not set: clear rewrite rules + */ - iPtr->ensembleRewrite.sourceObjs = NULL; + iPtr->ensembleRewrite.sourceObjs = NULL; - if (flags & TCL_EVAL_GLOBAL) { - /* TODO: Check we do this whenever needed. */ - TEOV_SwitchVarFrame(interp); - lookupNsPtr = iPtr->globalNsPtr; - } + if (flags & TCL_EVAL_GLOBAL) { + TEOV_SwitchVarFrame(interp); + lookupNsPtr = iPtr->globalNsPtr; } + } + reresolve: + if (preCmdPtr) { + if (preCmdPtr->flags & CMD_IS_DELETED) { + Tcl_SetObjResult(interp, Tcl_ObjPrintf( + "attempt to invoke a deleted command")); + Tcl_SetErrorCode(interp, "TCL", "EVAL", "DELETEDCOMMAND", NULL); + return TCL_ERROR; + } + cmdPtr = preCmdPtr; + } else { cmdPtr = TEOV_LookupCmdFromObj(interp, objv[0], lookupNsPtr); if (!cmdPtr) { return TEOV_NotFound(interp, objc, objv, lookupNsPtr); } - } - if (iPtr->tracePtr || (cmdPtr->flags & CMD_HAS_EXEC_TRACES)) { - /* - * Call enter traces. They will schedule a call to the leave traces if - * necessary. - */ - - int traceCode = TCL_OK; - int cmdEpoch = cmdPtr->cmdEpoch; - int newEpoch; - const char *command; - int length, deleted; + if (enterTracesDone || iPtr->tracePtr + || (cmdPtr->flags & CMD_HAS_EXEC_TRACES)) { Tcl_Obj *commandPtr = TclGetSourceFromFrame( flags & TCL_EVAL_SOURCE_IN_FRAME ? iPtr->cmdFramePtr : NULL, objc, objv); - Tcl_IncrRefCount(commandPtr); - command = Tcl_GetStringFromObj(commandPtr, &length); - /* - * Call trace functions. - * Execute any command or execution traces. Note that we bump up the - * command's reference count for the duration of the calling of the - * traces so that the structure doesn't go away underneath our feet. - */ + if (!enterTracesDone) { - cmdPtr->refCount++; - if (iPtr->tracePtr) { - traceCode = TclCheckInterpTraces(interp, command, length, - cmdPtr, TCL_OK, TCL_TRACE_ENTER_EXEC, objc, objv); - } - if ((cmdPtr->flags & CMD_HAS_EXEC_TRACES) && (traceCode == TCL_OK)) { - traceCode = TclCheckExecutionTraces(interp, command, length, - cmdPtr, TCL_OK, TCL_TRACE_ENTER_EXEC, objc, objv); - } - newEpoch = cmdPtr->cmdEpoch; - deleted = cmdPtr->flags & CMD_IS_DELETED; - TclCleanupCommandMacro(cmdPtr); - - if (traceCode != TCL_OK) { - Tcl_DecrRefCount(commandPtr); - return traceCode; - } - - if (cmdEpoch != newEpoch) { + int code = TEOV_RunEnterTraces(interp, &cmdPtr, commandPtr, + objc, objv); /* - * The traces did something to the traced command. How should - * we respond? - * - * If we got the trace command by looking up a command name, we - * should just look it up again. + * Send any exception from enter traces back as an exception + * raised by the traced command. */ - if (preCmdPtr == NULL) { - cmdPtr = TEOV_LookupCmdFromObj(interp, objv[0], lookupNsPtr); - } else { - /* - * If we did not look up a command name, we got the cmdPtr - * from a caller. If that cmdPtr has been deleted, we need - * to avoid a crash. Otherwise, press on. We don't have - * any foundation to claim a better answer. - */ - if (deleted) { - cmdPtr = NULL; - } + if (code != TCL_OK) { + Tcl_DecrRefCount(commandPtr); + return code; } - } - if (cmdPtr) { /* - * Command was found: push a record to schedule the leave traces. + * If the enter traces made the resolved cmdPtr unusable, go + * back and resolve again, but next time don't run enter + * traces again. */ - TclNRAddCallback(interp, TEOV_RunLeaveTraces, INT2PTR(objc), - commandPtr, cmdPtr, objv); - cmdPtr->refCount++; - } else { - Tcl_DecrRefCount(commandPtr); - } - - if (cmdPtr == NULL) { - if (preCmdPtr == NULL) { - return TEOV_NotFound(interp, objc, objv, lookupNsPtr); + if (cmdPtr == NULL) { + enterTracesDone = 1; + Tcl_DecrRefCount(commandPtr); + goto reresolve; } - /* Is this right??? */ - return TCL_OK; } + + /* + * Schedule leave traces. Raise the refCount on the resolved + * cmdPtr, so that when it passes to the leave traces we know + * it's still valid. + */ + + cmdPtr->refCount++; + TclNRAddCallback(interp, TEOV_RunLeaveTraces, INT2PTR(objc), + commandPtr, cmdPtr, objv); } TclNRAddCallback(interp, Dispatch, @@ -4672,26 +4635,19 @@ TEOV_RunEnterTraces( Command **cmdPtrPtr, Tcl_Obj *commandPtr, int objc, - Tcl_Obj *const objv[], - Namespace *lookupNsPtr, - int weLookUp) + Tcl_Obj *const objv[]) { Interp *iPtr = (Interp *) interp; Command *cmdPtr = *cmdPtrPtr; - int traceCode = TCL_OK; - int cmdEpoch = cmdPtr->cmdEpoch; - int newEpoch; - const char *command; - int length, deleted; - - Tcl_IncrRefCount(commandPtr); - command = Tcl_GetStringFromObj(commandPtr, &length); + int newEpoch, cmdEpoch = cmdPtr->cmdEpoch; + int length, traceCode = TCL_OK; + const char *command = Tcl_GetStringFromObj(commandPtr, &length); /* * Call trace functions. * Execute any command or execution traces. Note that we bump up the - * command's reference count for the duration of the calling of the traces - * so that the structure doesn't go away underneath our feet. + * command's reference count for the duration of the calling of the + * traces so that the structure doesn't go away underneath our feet. */ cmdPtr->refCount++; @@ -4704,47 +4660,15 @@ TEOV_RunEnterTraces( cmdPtr, TCL_OK, TCL_TRACE_ENTER_EXEC, objc, objv); } newEpoch = cmdPtr->cmdEpoch; - deleted = cmdPtr->flags & CMD_IS_DELETED; TclCleanupCommandMacro(cmdPtr); - if (cmdEpoch != newEpoch) { - - /* - * The traces did something to the traced command. How should - * we respond? - * - * If we got the trace command by looking up a command name, we - * should just look it up again. - */ - if (weLookUp) { - cmdPtr = TEOV_LookupCmdFromObj(interp, objv[0], lookupNsPtr); - } else { - - /* - * If we did not look up a command name, we got the cmdPtr - * from a caller. If that cmdPtr has been deleted, we need - * to avoid a crash. Otherwise, press on. We don't have - * any foundation to claim a better answer. - */ - if (deleted) { - cmdPtr = NULL; - } - } - *cmdPtrPtr = cmdPtr; + if (traceCode != TCL_OK) { + return traceCode; } - - if (cmdPtr && (traceCode == TCL_OK)) { - /* - * Command was found: push a record to schedule the leave traces. - */ - - TclNRAddCallback(interp, TEOV_RunLeaveTraces, INT2PTR(objc), - commandPtr, cmdPtr, objv); - cmdPtr->refCount++; - } else { - Tcl_DecrRefCount(commandPtr); + if (cmdEpoch != newEpoch) { + *cmdPtrPtr = NULL; } - return traceCode; + return TCL_OK; } static int -- cgit v0.12