diff options
Diffstat (limited to 'generic/tclProc.c')
| -rw-r--r-- | generic/tclProc.c | 152 |
1 files changed, 139 insertions, 13 deletions
diff --git a/generic/tclProc.c b/generic/tclProc.c index 4d9dcfd..855cd92 100644 --- a/generic/tclProc.c +++ b/generic/tclProc.c @@ -10,7 +10,7 @@ * See the file "license.terms" for information on usage and redistribution * of this file, and for a DISCLAIMER OF ALL WARRANTIES. * - * RCS: @(#) $Id: tclProc.c,v 1.56 2004/09/26 16:36:04 msofer Exp $ + * RCS: @(#) $Id: tclProc.c,v 1.57 2004/10/01 12:45:20 dkf Exp $ */ #include "tclInt.h" @@ -41,6 +41,20 @@ Tcl_ObjType tclProcBodyType = { ProcBodyUpdateString, /* UpdateString procedure */ ProcBodySetFromAny /* SetFromAny procedure */ }; + +/* + * The [upvar]/[uplevel] level reference type. Uses the twoPtrValue + * field, encoding the type of level reference in ptr1 and the actual + * parsed out offset in ptr2. + * + * Uses the default behaviour throughout, and never disposes of the + * string rep; it's just a cache type. + */ + +Tcl_ObjType tclLevelReferenceType = { + "levelReference", + NULL, NULL, NULL, NULL +}; /* *---------------------------------------------------------------------- @@ -538,9 +552,9 @@ procError: */ int -TclGetFrame(interp, string, framePtrPtr) +TclGetFrame(interp, name, framePtrPtr) Tcl_Interp *interp; /* Interpreter in which to find frame. */ - CONST char *string; /* String describing frame. */ + CONST char *name; /* String describing frame. */ CallFrame **framePtrPtr; /* Store pointer to frame here (or NULL * if global frame indicated). */ { @@ -554,18 +568,18 @@ TclGetFrame(interp, string, framePtrPtr) result = 1; curLevel = (iPtr->varFramePtr == NULL) ? 0 : iPtr->varFramePtr->level; - if (*string == '#') { - if (Tcl_GetInt(interp, string+1, &level) != TCL_OK) { + if (*name== '#') { + if (Tcl_GetInt(interp, name+1, &level) != TCL_OK) { return -1; } if (level < 0) { levelError: - Tcl_AppendResult(interp, "bad level \"", string, "\"", + Tcl_AppendResult(interp, "bad level \"", name, "\"", (char *) NULL); return -1; } - } else if (isdigit(UCHAR(*string))) { /* INTL: digit */ - if (Tcl_GetInt(interp, string, &level) != TCL_OK) { + } else if (isdigit(UCHAR(*name))) { /* INTL: digit */ + if (Tcl_GetInt(interp, name, &level) != TCL_OK) { return -1; } level = curLevel - level; @@ -574,11 +588,121 @@ TclGetFrame(interp, string, framePtrPtr) result = 0; } + /* Figure out which frame to use, and return it to the caller */ + + if (level == 0) { + framePtr = NULL; + } else { + for (framePtr = iPtr->varFramePtr; framePtr != NULL; + framePtr = framePtr->callerVarPtr) { + if (framePtr->level == level) { + break; + } + } + if (framePtr == NULL) { + goto levelError; + } + } + *framePtrPtr = framePtr; + return result; +} + +/* + *---------------------------------------------------------------------- + * + * TclObjGetFrame -- + * + * Given a description of a procedure frame, such as the first + * argument to an "uplevel" or "upvar" command, locate the + * call frame for the appropriate level of procedure. + * + * Results: + * The return value is -1 if an error occurred in finding the frame + * (in this case an error message is left in the interp's result). + * 1 is returned if objPtr was either a number or a number preceded + * by "#" and it specified a valid frame. 0 is returned if objPtr + * isn't one of the two things above (in this case, the lookup + * acts as if objPtr were "1"). The variable pointed to by + * framePtrPtr is filled in with the address of the desired frame + * (unless an error occurs, in which case it isn't modified). + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +int +TclObjGetFrame(interp, objPtr, framePtrPtr) + Tcl_Interp *interp; /* Interpreter in which to find frame. */ + Tcl_Obj *objPtr; /* Object describing frame. */ + CallFrame **framePtrPtr; /* Store pointer to frame here (or NULL + * if global frame indicated). */ +{ + register Interp *iPtr = (Interp *) interp; + int curLevel, level, result; + CallFrame *framePtr; + CONST char *name = TclGetString(objPtr); + /* - * Figure out which frame to use, and modify the interpreter so - * its variables come from that frame. + * Parse object to figure out which level number to go to. */ + result = 1; + curLevel = (iPtr->varFramePtr == NULL) ? 0 : iPtr->varFramePtr->level; + if (objPtr->typePtr == &tclLevelReferenceType) { + if ((int) objPtr->internalRep.twoPtrValue.ptr1) { + level = curLevel - (int) objPtr->internalRep.twoPtrValue.ptr2; + } else { + level = (int) objPtr->internalRep.twoPtrValue.ptr2; + } + if (level < 0) { + goto levelError; + } + } else if (objPtr->typePtr == &tclIntType || + objPtr->typePtr == &tclWideIntType) { + if (Tcl_GetIntFromObj(NULL, objPtr, &level) != TCL_OK || level < 0) { + goto levelError; + } + level = curLevel - level; + } else { + if (*name == '#') { + if (Tcl_GetInt(interp, name+1, &level) != TCL_OK) { + return -1; + } + if (level < 0) { + goto levelError; + } + /* + * Cache for future reference. + */ + TclFreeIntRep(objPtr); + objPtr->typePtr = &tclLevelReferenceType; + objPtr->internalRep.twoPtrValue.ptr1 = (VOID *) 0; + objPtr->internalRep.twoPtrValue.ptr2 = (VOID *) level; + } else if (isdigit(UCHAR(*name))) { /* INTL: digit */ + if (Tcl_GetInt(interp, name, &level) != TCL_OK) { + return -1; + } + /* + * Cache for future reference. + */ + TclFreeIntRep(objPtr); + objPtr->typePtr = &tclLevelReferenceType; + objPtr->internalRep.twoPtrValue.ptr1 = (VOID *) 1; + objPtr->internalRep.twoPtrValue.ptr2 = (VOID *) level; + level = curLevel - level; + } else { + /* + * Don't cache as the object *isn't* a level reference. + */ + level = curLevel - 1; + result = 0; + } + } + + /* Figure out which frame to use, and return it to the caller */ + if (level == 0) { framePtr = NULL; } else { @@ -594,6 +718,10 @@ TclGetFrame(interp, string, framePtrPtr) } *framePtrPtr = framePtr; return result; + +levelError: + Tcl_AppendResult(interp, "bad level \"", name, "\"", (char *) NULL); + return -1; } /* @@ -622,7 +750,6 @@ Tcl_UplevelObjCmd(dummy, interp, objc, objv) Tcl_Obj *CONST objv[]; /* Argument objects. */ { register Interp *iPtr = (Interp *) interp; - char *optLevel; int result; CallFrame *savedVarFramePtr, *framePtr; @@ -636,8 +763,7 @@ Tcl_UplevelObjCmd(dummy, interp, objc, objv) * Find the level to use for executing the command. */ - optLevel = TclGetString(objv[1]); - result = TclGetFrame(interp, optLevel, &framePtr); + result = TclObjGetFrame(interp, objv[1], &framePtr); if (result == -1) { return TCL_ERROR; } |