/* * tclVar.c -- * * This file contains routines that implement Tcl variables * (both scalars and arrays). * * The implementation of arrays is modelled after an initial * implementation by Karl Lehenbauer, Mark Diekhans and * Peter da Silva. * * Copyright 1987-1991 Regents of the University of California * Permission to use, copy, modify, and distribute this * software and its documentation for any purpose and without * fee is hereby granted, provided that the above copyright * notice appear in all copies. The University of California * makes no representations about the suitability of this * software for any purpose. It is provided "as is" without * express or implied warranty. */ #ifndef lint static char rcsid[] = "$Header: /user6/ouster/tcl/RCS/tclVar.c,v 1.27 92/05/07 09:24:59 ouster Exp $ SPRITE (Berkeley)"; #endif #include "tclInt.h" /* * The strings below are used to indicate what went wrong when a * variable access is denied. */ static char *noSuchVar = "no such variable"; static char *isArray = "variable is array"; static char *needArray = "variable isn't array"; static char *noSuchElement = "no such element in array"; static char *traceActive = "trace is active on variable"; /* * Forward references to procedures defined later in this file: */ static char * CallTraces _ANSI_ARGS_((Interp *iPtr, Var *arrayPtr, Tcl_HashEntry *hPtr, char *name1, char *name2, int flags)); static void DeleteSearches _ANSI_ARGS_((Var *arrayVarPtr)); static void DeleteArray _ANSI_ARGS_((Interp *iPtr, char *arrayName, Var *varPtr, int flags)); static Var * NewVar _ANSI_ARGS_((int space)); static ArraySearch * ParseSearchId _ANSI_ARGS_((Tcl_Interp *interp, Var *varPtr, char *varName, char *string)); static void VarErrMsg _ANSI_ARGS_((Tcl_Interp *interp, char *name1, char *name2, char *operation, char *reason)); /* *---------------------------------------------------------------------- * * Tcl_GetVar -- * * Return the value of a Tcl variable. * * Results: * The return value points to the current value of varName. If * the variable is not defined or can't be read because of a clash * in array usage then a NULL pointer is returned and an error * message is left in interp->result if the TCL_LEAVE_ERR_MSG * flag is set. Note: the return value is only valid up until * the next call to Tcl_SetVar or Tcl_SetVar2; if you depend on * the value lasting longer than that, then make yourself a private * copy. * * Side effects: * None. * *---------------------------------------------------------------------- */ char * Tcl_GetVar(interp, varName, flags) Tcl_Interp *interp; /* Command interpreter in which varName is * to be looked up. */ char *varName; /* Name of a variable in interp. */ int flags; /* OR-ed combination of TCL_GLOBAL_ONLY * or TCL_LEAVE_ERR_MSG bits. */ { register char *p; /* * If varName refers to an array (it ends with a parenthesized * element name), then handle it specially. */ for (p = varName; *p != '\0'; p++) { if (*p == '(') { char *result; char *open = p; do { p++; } while (*p != '\0'); p--; if (*p != ')') { goto scalar; } *open = '\0'; *p = '\0'; result = Tcl_GetVar2(interp, varName, open+1, flags); *open = '('; *p = ')'; return result; } } scalar: return Tcl_GetVar2(interp, varName, (char *) NULL, flags); } /* *---------------------------------------------------------------------- * * Tcl_GetVar2 -- * * Return the value of a Tcl variable, given a two-part name * consisting of array name and element within array. * * Results: * The return value points to the current value of the variable * given by name1 and name2. If the specified variable doesn't * exist, or if there is a clash in array usage, then NULL is * returned and a message will be left in interp->result if the * TCL_LEAVE_ERR_MSG flag is set. Note: the return value is * only valid up until the next call to Tcl_SetVar or Tcl_SetVar2; * if you depend on the value lasting longer than that, then make * yourself a private copy. * * Side effects: * None. * *---------------------------------------------------------------------- */ char * Tcl_GetVar2(interp, name1, name2, flags) Tcl_Interp *interp; /* Command interpreter in which variable is * to be looked up. */ char *name1; /* Name of array (if name2 is NULL) or * name of variable. */ char *name2; /* If non-null, gives name of element in * array. */ int flags; /* OR-ed combination of TCL_GLOBAL_ONLY * or TCL_LEAVE_ERR_MSG bits. */ { Tcl_HashEntry *hPtr; Var *varPtr; Interp *iPtr = (Interp *) interp; Var *arrayPtr = NULL; /* * Lookup the first name. */ if ((flags & TCL_GLOBAL_ONLY) || (iPtr->varFramePtr == NULL)) { hPtr = Tcl_FindHashEntry(&iPtr->globalTable, name1); } else { hPtr = Tcl_FindHashEntry(&iPtr->varFramePtr->varTable, name1); } if (hPtr == NULL) { if (flags & TCL_LEAVE_ERR_MSG) { VarErrMsg(interp, name1, name2, "read", noSuchVar); } return NULL; } varPtr = (Var *) Tcl_GetHashValue(hPtr); if (varPtr->flags & VAR_UPVAR) { hPtr = varPtr->value.upvarPtr; varPtr = (Var *) Tcl_GetHashValue(hPtr); } /* * If this is an array reference, then remember the traces on the array * and lookup the element within the array. */ if (name2 != NULL) { if (varPtr->flags & VAR_UNDEFINED) { if (flags & TCL_LEAVE_ERR_MSG) { VarErrMsg(interp, name1, name2, "read", noSuchVar); } return NULL; } else if (!(varPtr->flags & VAR_ARRAY)) { if (flags & TCL_LEAVE_ERR_MSG) { VarErrMsg(interp, name1, name2, "read", needArray); } return NULL; } arrayPtr = varPtr; hPtr = Tcl_FindHashEntry(varPtr->value.tablePtr, name2); if (hPtr == NULL) { if (flags & TCL_LEAVE_ERR_MSG) { VarErrMsg(interp, name1, name2, "read", noSuchElement); } return NULL; } varPtr = (Var *) Tcl_GetHashValue(hPtr); } /* * Invoke any traces that have been set for the variable. */ if ((varPtr->tracePtr != NULL) || ((arrayPtr != NULL) && (arrayPtr->tracePtr != NULL))) { char *msg; msg = CallTraces(iPtr, arrayPtr, hPtr, name1, name2, (flags & TCL_GLOBAL_ONLY) | TCL_TRACE_READS); if (msg != NULL) { VarErrMsg(interp, name1, name2, "read", msg); return NULL; } /* * Watch out! The variable could have gotten re-allocated to * a larger size. Fortunately the hash table entry will still * be around. */ varPtr = (Var *) Tcl_GetHashValue(hPtr); } if (varPtr->flags & (VAR_UNDEFINED|VAR_UPVAR|VAR_ARRAY)) { if (flags & TCL_LEAVE_ERR_MSG) { VarErrMsg(interp, name1, name2, "read", noSuchVar); } return NULL; } return varPtr->value.string; } /* *---------------------------------------------------------------------- * * Tcl_SetVar -- * * Change the value of a variable. * * Results: * Returns a pointer to the malloc'ed string holding the new * value of the variable. The caller should not modify this * string. If the write operation was disallowed then NULL * is returned; if the TCL_LEAVE_ERR_MSG flag is set, then * an explanatory message will be left in interp->result. * * Side effects: * If varName is defined as a local or global variable in interp, * its value is changed to newValue. If varName isn't currently * defined, then a new global variable by that name is created. * *---------------------------------------------------------------------- */ char * Tcl_SetVar(interp, varName, newValue, flags) Tcl_Interp *interp; /* Command interpreter in which varName is * to be looked up. */ char *varName; /* Name of a variable in interp. */ char *newValue; /* New value for varName. */ int flags; /* Various flags that tell how to set value: * any of TCL_GLOBAL_ONLY, TCL_APPEND_VALUE, * TCL_LIST_ELEMENT, TCL_NO_SPACE, or * TCL_LEAVE_ERR_MSG. */ { register char *p; /* * If varName refers to an array (it ends with a parenthesized * element name), then handle it specially. */ for (p = varName; *p != '\0'; p++) { if (*p == '(') { char *result; char *open = p; do { p++; } while (*p != '\0'); p--; if (*p != ')') { goto scalar; } *open = '\0'; *p = '\0'; result = Tcl_SetVar2(interp, varName, open+1, newValue, flags); *open = '('; *p = ')'; return result; } } scalar: return Tcl_SetVar2(interp, varName, (char *) NULL, newValue, flags); } /* *---------------------------------------------------------------------- * * Tcl_SetVar2 -- * * Given a two-part variable name, which may refer either to a * scalar variable or an element of an array, change the value * of the variable. If the named scalar or array or element * doesn't exist then create one. * * Results: * Returns a pointer to the malloc'ed string holding the new * value of the variable. The caller should not modify this * string. If the write operation was disallowed because an * array was expected but not found (or vice versa), then NULL * is returned; if the TCL_LEAVE_ERR_MSG flag is set, then * an explanatory message will be left in interp->result. * * Side effects: * The value of the given variable is set. If either the array * or the entry didn't exist then a new one is created. * *---------------------------------------------------------------------- */ char * Tcl_SetVar2(interp, name1, name2, newValue, flags) Tcl_Interp *interp; /* Command interpreter in which variable is * to be looked up. */ char *name1; /* If name2 is NULL, this is name of scalar * variable. Otherwise it is name of array. */ char *name2; /* Name of an element within array, or NULL. */ char *newValue; /* New value for variable. */ int flags; /* Various flags that tell how to set value: * any of TCL_GLOBAL_ONLY, TCL_APPEND_VALUE, * TCL_LIST_ELEMENT, and TCL_NO_SPACE, or * TCL_LEAVE_ERR_MSG . */ { Tcl_HashEntry *hPtr; register Var *varPtr = NULL; /* Initial value only used to stop compiler * from complaining; not really needed. */ register Interp *iPtr = (Interp *) interp; int length, new, listFlags; Var *arrayPtr = NULL; /* * Lookup the first name. */ if ((flags & TCL_GLOBAL_ONLY) || (iPtr->varFramePtr == NULL)) { hPtr = Tcl_CreateHashEntry(&iPtr->globalTable, name1, &new); } else { hPtr = Tcl_CreateHashEntry(&iPtr->varFramePtr->varTable, name1, &new); } if (!new) { varPtr = (Var *) Tcl_GetHashValue(hPtr); if (varPtr->flags & VAR_UPVAR) { hPtr = varPtr->value.upvarPtr; varPtr = (Var *) Tcl_GetHashValue(hPtr); } } /* * If this is an array reference, then create a new array (if * needed), remember any traces on the array, and lookup the * element within the array. */ if (name2 != NULL) { if (new) { varPtr = NewVar(0); Tcl_SetHashValue(hPtr, varPtr); varPtr->flags = VAR_ARRAY; varPtr->value.tablePtr = (Tcl_HashTable *) ckalloc(sizeof(Tcl_HashTable)); Tcl_InitHashTable(varPtr->value.tablePtr, TCL_STRING_KEYS); } else { if (varPtr->flags & VAR_UNDEFINED) { varPtr->flags = VAR_ARRAY; varPtr->value.tablePtr = (Tcl_HashTable *) ckalloc(sizeof(Tcl_HashTable)); Tcl_InitHashTable(varPtr->value.tablePtr, TCL_STRING_KEYS); } else if (!(varPtr->flags & VAR_ARRAY)) { if (flags & TCL_LEAVE_ERR_MSG) { VarErrMsg(interp, name1, name2, "set", needArray); } return NULL; } arrayPtr = varPtr; } hPtr = Tcl_CreateHashEntry(varPtr->value.tablePtr, name2, &new); } /* * Compute how many bytes will be needed for newValue (leave space * for a separating space between list elements). */ if (flags & TCL_LIST_ELEMENT) { length = Tcl_ScanElement(newValue, &listFlags) + 1; } else { length = strlen(newValue); } /* * If the variable doesn't exist then create a new one. If it * does exist then clear its current value unless this is an * append operation. */ if (new) { varPtr = NewVar(length); Tcl_SetHashValue(hPtr, varPtr); if ((arrayPtr != NULL) && (arrayPtr->searchPtr != NULL)) { DeleteSearches(arrayPtr); } } else { varPtr = (Var *) Tcl_GetHashValue(hPtr); if (varPtr->flags & VAR_ARRAY) { if (flags & TCL_LEAVE_ERR_MSG) { VarErrMsg(interp, name1, name2, "set", isArray); } return NULL; } if (!(flags & TCL_APPEND_VALUE) || (varPtr->flags & VAR_UNDEFINED)) { varPtr->valueLength = 0; } } /* * Make sure there's enough space to hold the variable's * new value. If not, enlarge the variable's space. */ if ((length + varPtr->valueLength) >= varPtr->valueSpace) { Var *newVarPtr; int newSize; newSize = 2*varPtr->valueSpace; if (newSize <= (length + varPtr->valueLength)) { newSize += length; } newVarPtr = NewVar(newSize); newVarPtr->valueLength = varPtr->valueLength; newVarPtr->upvarUses = varPtr->upvarUses; newVarPtr->tracePtr = varPtr->tracePtr; strcpy(newVarPtr->value.string, varPtr->value.string); Tcl_SetHashValue(hPtr, newVarPtr); ckfree((char *) varPtr); varPtr = newVarPtr; } /* * Append the new value to the variable, either as a list * element or as a string. */ if (flags & TCL_LIST_ELEMENT) { if ((varPtr->valueLength > 0) && !(flags & TCL_NO_SPACE)) { varPtr->value.string[varPtr->valueLength] = ' '; varPtr->valueLength++; } varPtr->valueLength += Tcl_ConvertElement(newValue, varPtr->value.string + varPtr->valueLength, listFlags); varPtr->value.string[varPtr->valueLength] = 0; } else { strcpy(varPtr->value.string + varPtr->valueLength, newValue); varPtr->valueLength += length; } varPtr->flags &= ~VAR_UNDEFINED; /* * Invoke any write traces for the variable. */ if ((varPtr->tracePtr != NULL) || ((arrayPtr != NULL) && (arrayPtr->tracePtr != NULL))) { char *msg; msg = CallTraces(iPtr, arrayPtr, hPtr, name1, name2, (flags & TCL_GLOBAL_ONLY) | TCL_TRACE_WRITES); if (msg != NULL) { VarErrMsg(interp, name1, name2, "set", msg); return NULL; } /* * Watch out! The variable could have gotten re-allocated to * a larger size. Fortunately the hash table entry will still * be around. */ varPtr = (Var *) Tcl_GetHashValue(hPtr); } return varPtr->value.string; } /* *---------------------------------------------------------------------- * * Tcl_UnsetVar -- * * Delete a variable, so that it may not be accessed anymore. * * Results: * Returns 0 if the variable was successfully deleted, -1 * if the variable can't be unset. In the event of an error, * if the TCL_LEAVE_ERR_MSG flag is set then an error message * is left in interp->result. * * Side effects: * If varName is defined as a local or global variable in interp, * it is deleted. * *---------------------------------------------------------------------- */ int Tcl_UnsetVar(interp, varName, flags) Tcl_Interp *interp; /* Command interpreter in which varName is * to be looked up. */ char *varName; /* Name of a variable in interp. May be * either a scalar name or an array name * or an element in an array. */ int flags; /* OR-ed combination of any of * TCL_GLOBAL_ONLY or TCL_LEAVE_ERR_MSG. */ { register char *p; int result; /* * Figure out whether this is an array reference, then call * Tcl_UnsetVar2 to do all the real work. */ for (p = varName; *p != '\0'; p++) { if (*p == '(') { char *open = p; do { p++; } while (*p != '\0'); p--; if (*p != ')') { goto scalar; } *open = '\0'; *p = '\0'; result = Tcl_UnsetVar2(interp, varName, open+1, flags); *open = '('; *p = ')'; return result; } } scalar: return Tcl_UnsetVar2(interp, varName, (char *) NULL, flags); } /* *---------------------------------------------------------------------- * * Tcl_UnsetVar2 -- * * Delete a variable, given a 2-part name. * * Results: * Returns 0 if the variable was successfully deleted, -1 * if the variable can't be unset. In the event of an error, * if the TCL_LEAVE_ERR_MSG flag is set then an error message * is left in interp->result. * * Side effects: * If name1 and name2 indicate a local or global variable in interp, * it is deleted. If name1 is an array name and name2 is NULL, then * the whole array is deleted. * *---------------------------------------------------------------------- */ int Tcl_UnsetVar2(interp, name1, name2, flags) Tcl_Interp *interp; /* Command interpreter in which varName is * to be looked up. */ char *name1; /* Name of variable or array. */ char *name2; /* Name of element within array or NULL. */ int flags; /* OR-ed combination of any of * TCL_GLOBAL_ONLY or TCL_LEAVE_ERR_MSG. */ { Tcl_HashEntry *hPtr, dummyEntry; Var *varPtr, dummyVar; Interp *iPtr = (Interp *) interp; Var *arrayPtr = NULL; if ((flags & TCL_GLOBAL_ONLY) || (iPtr->varFramePtr == NULL)) { hPtr = Tcl_FindHashEntry(&iPtr->globalTable, name1); } else { hPtr = Tcl_FindHashEntry(&iPtr->varFramePtr->varTable, name1); } if (hPtr == NULL) { if (flags & TCL_LEAVE_ERR_MSG) { VarErrMsg(interp, name1, name2, "unset", noSuchVar); } return -1; } varPtr = (Var *) Tcl_GetHashValue(hPtr); /* * For global variables referenced in procedures, leave the procedure's * reference variable in place, but unset the global variable. Can't * decrement the actual variable's use count, since we didn't delete * the reference variable. */ if (varPtr->flags & VAR_UPVAR) { hPtr = varPtr->value.upvarPtr; varPtr = (Var *) Tcl_GetHashValue(hPtr); } /* * If the variable being deleted is an element of an array, then * remember trace procedures on the overall array and find the * element to delete. */ if (name2 != NULL) { if (!(varPtr->flags & VAR_ARRAY)) { if (flags & TCL_LEAVE_ERR_MSG) { VarErrMsg(interp, name1, name2, "unset", needArray); } return -1; } if (varPtr->searchPtr != NULL) { DeleteSearches(varPtr); } arrayPtr = varPtr; hPtr = Tcl_FindHashEntry(varPtr->value.tablePtr, name2); if (hPtr == NULL) { if (flags & TCL_LEAVE_ERR_MSG) { VarErrMsg(interp, name1, name2, "unset", noSuchElement); } return -1; } varPtr = (Var *) Tcl_GetHashValue(hPtr); } /* * If there is a trace active on this variable or if the variable * is already being deleted then don't delete the variable: it * isn't safe, since there are procedures higher up on the stack * that will use pointers to the variable. Also don't delete an * array if there are traces active on any of its elements. */ if (varPtr->flags & (VAR_TRACE_ACTIVE|VAR_ELEMENT_ACTIVE)) { if (flags & TCL_LEAVE_ERR_MSG) { VarErrMsg(interp, name1, name2, "unset", traceActive); } return -1; } /* * The code below is tricky, because of the possibility that * a trace procedure might try to access a variable being * deleted. To handle this situation gracefully, copy the * contents of the variable and its hash table entry to * dummy variables, then clean up the actual variable so that * it's been completely deleted before the traces are called. * Then call the traces, and finally clean up the variable's * storage using the dummy copies. */ dummyVar = *varPtr; Tcl_SetHashValue(&dummyEntry, &dummyVar); if (varPtr->upvarUses == 0) { Tcl_DeleteHashEntry(hPtr); ckfree((char *) varPtr); } else { varPtr->flags = VAR_UNDEFINED; varPtr->tracePtr = NULL; } /* * Call trace procedures for the variable being deleted and delete * its traces. */ if ((dummyVar.tracePtr != NULL) || ((arrayPtr != NULL) && (arrayPtr->tracePtr != NULL))) { (void) CallTraces(iPtr, arrayPtr, &dummyEntry, name1, name2, (flags & TCL_GLOBAL_ONLY) | TCL_TRACE_UNSETS); while (dummyVar.tracePtr != NULL) { VarTrace *tracePtr = dummyVar.tracePtr; dummyVar.tracePtr = tracePtr->nextPtr; ckfree((char *) tracePtr); } } /* * If the variable is an array, delete all of its elements. This * must be done after calling the traces on the array, above (that's * the way traces are defined). */ if (dummyVar.flags & VAR_ARRAY) { DeleteArray(iPtr, name1, &dummyVar, (flags & TCL_GLOBAL_ONLY) | TCL_TRACE_UNSETS); } if (dummyVar.flags & VAR_UNDEFINED) { if (flags & TCL_LEAVE_ERR_MSG) { VarErrMsg(interp, name1, name2, "unset", (name2 == NULL) ? noSuchVar : noSuchElement); } return -1; } return 0; } /* *---------------------------------------------------------------------- * * Tcl_TraceVar -- * * Arrange for reads and/or writes to a variable to cause a * procedure to be invoked, which can monitor the operations * and/or change their actions. * * Results: * A standard Tcl return value. * * Side effects: * A trace is set up on the variable given by varName, such that * future references to the variable will be intermediated by * proc. See the manual entry for complete details on the calling * sequence for proc. * *---------------------------------------------------------------------- */ int Tcl_TraceVar(interp, varName, flags, proc, clientData) Tcl_Interp *interp; /* Interpreter in which variable is * to be traced. */ char *varName; /* Name of variable; may end with "(index)" * to signify an array reference. */ int flags; /* OR-ed collection of bits, including any * of TCL_TRACE_READS, TCL_TRACE_WRITES, * TCL_TRACE_UNSETS, and TCL_GLOBAL_ONLY. */ Tcl_VarTraceProc *proc; /* Procedure to call when specified ops are * invoked upon varName. */ ClientData clientData; /* Arbitrary argument to pass to proc. */ { register char *p; /* * If varName refers to an array (it ends with a parenthesized * element name), then handle it specially. */ for (p = varName; *p != '\0'; p++) { if (*p == '(') { int result; char *open = p; do { p++; } while (*p != '\0'); p--; if (*p != ')') { goto scalar; } *open = '\0'; *p = '\0'; result = Tcl_TraceVar2(interp, varName, open+1, flags, proc, clientData); *open = '('; *p = ')'; return result; } } scalar: return Tcl_TraceVar2(interp, varName, (char *) NULL, flags, proc, clientData); } /* *---------------------------------------------------------------------- * * Tcl_TraceVar2 -- * * Arrange for reads and/or writes to a variable to cause a * procedure to be invoked, which can monitor the operations * and/or change their actions. * * Results: * A standard Tcl return value. * * Side effects: * A trace is set up on the variable given by name1 and name2, such * that future references to the variable will be intermediated by * proc. See the manual entry for complete details on the calling * sequence for proc. * *---------------------------------------------------------------------- */ int Tcl_TraceVar2(interp, name1, name2, flags, proc, clientData) Tcl_Interp *interp; /* Interpreter in which variable is * to be traced. */ char *name1; /* Name of scalar variable or array. */ char *name2; /* Name of element within array; NULL means * trace applies to scalar variable or array * as-a-whole. */ int flags; /* OR-ed collection of bits, including any * of TCL_TRACE_READS, TCL_TRACE_WRITES, * TCL_TRACE_UNSETS, and TCL_GLOBAL_ONLY. */ Tcl_VarTraceProc *proc; /* Procedure to call when specified ops are * invoked upon varName. */ ClientData clientData; /* Arbitrary argument to pass to proc. */ { Tcl_HashEntry *hPtr; Var *varPtr = NULL; /* Initial value only used to stop compiler * from complaining; not really needed. */ Interp *iPtr = (Interp *) interp; register VarTrace *tracePtr; int new; /* * Locate the variable, making a new (undefined) one if necessary. */ if ((flags & TCL_GLOBAL_ONLY) || (iPtr->varFramePtr == NULL)) { hPtr = Tcl_CreateHashEntry(&iPtr->globalTable, name1, &new); } else { hPtr = Tcl_CreateHashEntry(&iPtr->varFramePtr->varTable, name1, &new); } if (!new) { varPtr = (Var *) Tcl_GetHashValue(hPtr); if (varPtr->flags & VAR_UPVAR) { hPtr = varPtr->value.upvarPtr; varPtr = (Var *) Tcl_GetHashValue(hPtr); } } /* * If the trace is to be on an array element, make sure that the * variable is an array variable. If the variable doesn't exist * then define it as an empty array. Then find the specific * array element. */ if (name2 != NULL) { if (new) { varPtr = NewVar(0); Tcl_SetHashValue(hPtr, varPtr); varPtr->flags = VAR_ARRAY; varPtr->value.tablePtr = (Tcl_HashTable *) ckalloc(sizeof(Tcl_HashTable)); Tcl_InitHashTable(varPtr->value.tablePtr, TCL_STRING_KEYS); } else { if (varPtr->flags & VAR_UNDEFINED) { varPtr->flags = VAR_ARRAY; varPtr->value.tablePtr = (Tcl_HashTable *) ckalloc(sizeof(Tcl_HashTable)); Tcl_InitHashTable(varPtr->value.tablePtr, TCL_STRING_KEYS); } else if (!(varPtr->flags & VAR_ARRAY)) { iPtr->result = needArray; return TCL_ERROR; } } hPtr = Tcl_CreateHashEntry(varPtr->value.tablePtr, name2, &new); } if (new) { if ((name2 != NULL) && (varPtr->searchPtr != NULL)) { DeleteSearches(varPtr); } varPtr = NewVar(0); varPtr->flags = VAR_UNDEFINED; Tcl_SetHashValue(hPtr, varPtr); } else { varPtr = (Var *) Tcl_GetHashValue(hPtr); } /* * Set up trace information. */ tracePtr = (VarTrace *) ckalloc(sizeof(VarTrace)); tracePtr->traceProc = proc; tracePtr->clientData = clientData; tracePtr->flags = flags & (TCL_TRACE_READS|TCL_TRACE_WRITES|TCL_TRACE_UNSETS); tracePtr->nextPtr = varPtr->tracePtr; varPtr->tracePtr = tracePtr; return TCL_OK; } /* *---------------------------------------------------------------------- * * Tcl_UntraceVar -- * * Remove a previously-created trace for a variable. * * Results: * None. * * Side effects: * If there exists a trace for the variable given by varName * with the given flags, proc, and clientData, then that trace * is removed. * *---------------------------------------------------------------------- */ void Tcl_UntraceVar(interp, varName, flags, proc, clientData) Tcl_Interp *interp; /* Interpreter containing traced variable. */ char *varName; /* Name of variable; may end with "(index)" * to signify an array reference. */ int flags; /* OR-ed collection of bits describing * current trace, including any of * TCL_TRACE_READS, TCL_TRACE_WRITES, * TCL_TRACE_UNSETS, and TCL_GLOBAL_ONLY. */ Tcl_VarTraceProc *proc; /* Procedure assocated with trace. */ ClientData clientData; /* Arbitrary argument to pass to proc. */ { register char *p; /* * If varName refers to an array (it ends with a parenthesized * element name), then handle it specially. */ for (p = varName; *p != '\0'; p++) { if (*p == '(') { char *open = p; do { p++; } while (*p != '\0'); p--; if (*p != ')') { goto scalar; } *open = '\0'; *p = '\0'; Tcl_UntraceVar2(interp, varName, open+1, flags, proc, clientData); *open = '('; *p = ')'; return; } } scalar: Tcl_UntraceVar2(interp, varName, (char *) NULL, flags, proc, clientData); } /* *---------------------------------------------------------------------- * * Tcl_UntraceVar2 -- * * Remove a previously-created trace for a variable. * * Results: * None. * * Side effects: * If there exists a trace for the variable given by name1 * and name2 with the given flags, proc, and clientData, then * that trace is removed. * *---------------------------------------------------------------------- */ void Tcl_UntraceVar2(interp, name1, name2, flags, proc, clientData) Tcl_Interp *interp; /* Interpreter containing traced variable. */ char *name1; /* Name of variable or array. */ char *name2; /* Name of element within array; NULL means * trace applies to scalar variable or array * as-a-whole. */ int flags; /* OR-ed collection of bits describing * current trace, including any of * TCL_TRACE_READS, TCL_TRACE_WRITES, * TCL_TRACE_UNSETS, and TCL_GLOBAL_ONLY. */ Tcl_VarTraceProc *proc; /* Procedure assocated with trace. */ ClientData clientData; /* Arbitrary argument to pass to proc. */ { register VarTrace *tracePtr; VarTrace *prevPtr; Var *varPtr; Interp *iPtr = (Interp *) interp; Tcl_HashEntry *hPtr; ActiveVarTrace *activePtr; /* * First, lookup the variable. */ if ((flags & TCL_GLOBAL_ONLY) || (iPtr->varFramePtr == NULL)) { hPtr = Tcl_FindHashEntry(&iPtr->globalTable, name1); } else { hPtr = Tcl_FindHashEntry(&iPtr->varFramePtr->varTable, name1); } if (hPtr == NULL) { return; } varPtr = (Var *) Tcl_GetHashValue(hPtr); if (varPtr->flags & VAR_UPVAR) { hPtr = varPtr->value.upvarPtr; varPtr = (Var *) Tcl_GetHashValue(hPtr); } if (name2 != NULL) { if (!(varPtr->flags & VAR_ARRAY)) { return; } hPtr = Tcl_FindHashEntry(varPtr->value.tablePtr, name2); if (hPtr == NULL) { return; } varPtr = (Var *) Tcl_GetHashValue(hPtr); } flags &= (TCL_TRACE_READS | TCL_TRACE_WRITES | TCL_TRACE_UNSETS); for (tracePtr = varPtr->tracePtr, prevPtr = NULL; ; prevPtr = tracePtr, tracePtr = tracePtr->nextPtr) { if (tracePtr == NULL) { return; } if ((tracePtr->traceProc == proc) && (tracePtr->flags == flags) && (tracePtr->clientData == clientData)) { break; } } /* * The code below makes it possible to delete traces while traces * are active: it makes sure that the deleted trace won't be * processed by CallTraces. */ for (activePtr = iPtr->activeTracePtr; activePtr != NULL; activePtr = activePtr->nextPtr) { if (activePtr->nextTracePtr == tracePtr) { activePtr->nextTracePtr = tracePtr->nextPtr; } } if (prevPtr == NULL) { varPtr->tracePtr = tracePtr->nextPtr; } else { prevPtr->nextPtr = tracePtr->nextPtr; } ckfree((char *) tracePtr); } /* *---------------------------------------------------------------------- * * Tcl_VarTraceInfo -- * * Return the clientData value associated with a trace on a * variable. This procedure can also be used to step through * all of the traces on a particular variable that have the * same trace procedure. * * Results: * The return value is the clientData value associated with * a trace on the given variable. Information will only be * returned for a trace with proc as trace procedure. If * the clientData argument is NULL then the first such trace is * returned; otherwise, the next relevant one after the one * given by clientData will be returned. If the variable * doesn't exist, or if there are no (more) traces for it, * then NULL is returned. * * Side effects: * None. * *---------------------------------------------------------------------- */ ClientData Tcl_VarTraceInfo(interp, varName, flags, proc, prevClientData) Tcl_Interp *interp; /* Interpreter containing variable. */ char *varName; /* Name of variable; may end with "(index)" * to signify an array reference. */ int flags; /* 0 or TCL_GLOBAL_ONLY. */ Tcl_VarTraceProc *proc; /* Procedure assocated with trace. */ ClientData prevClientData; /* If non-NULL, gives last value returned * by this procedure, so this call will * return the next trace after that one. * If NULL, this call will return the * first trace. */ { register char *p; /* * If varName refers to an array (it ends with a parenthesized * element name), then handle it specially. */ for (p = varName; *p != '\0'; p++) { if (*p == '(') { ClientData result; char *open = p; do { p++; } while (*p != '\0'); p--; if (*p != ')') { goto scalar; } *open = '\0'; *p = '\0'; result = Tcl_VarTraceInfo2(interp, varName, open+1, flags, proc, prevClientData); *open = '('; *p = ')'; return result; } } scalar: return Tcl_VarTraceInfo2(interp, varName, (char *) NULL, flags, proc, prevClientData); } /* *---------------------------------------------------------------------- * * Tcl_VarTraceInfo2 -- * * Same as Tcl_VarTraceInfo, except takes name in two pieces * instead of one. * * Results: * Same as Tcl_VarTraceInfo. * * Side effects: * None. * *---------------------------------------------------------------------- */ ClientData Tcl_VarTraceInfo2(interp, name1, name2, flags, proc, prevClientData) Tcl_Interp *interp; /* Interpreter containing variable. */ char *name1; /* Name of variable or array. */ char *name2; /* Name of element within array; NULL means * trace applies to scalar variable or array * as-a-whole. */ int flags; /* 0 or TCL_GLOBAL_ONLY. */ Tcl_VarTraceProc *proc; /* Procedure assocated with trace. */ ClientData prevClientData; /* If non-NULL, gives last value returned * by this procedure, so this call will * return the next trace after that one. * If NULL, this call will return the * first trace. */ { register VarTrace *tracePtr; Var *varPtr; Interp *iPtr = (Interp *) interp; Tcl_HashEntry *hPtr; /* * First, lookup the variable. */ if ((flags & TCL_GLOBAL_ONLY) || (iPtr->varFramePtr == NULL)) { hPtr = Tcl_FindHashEntry(&iPtr->globalTable, name1); } else { hPtr = Tcl_FindHashEntry(&iPtr->varFramePtr->varTable, name1); } if (hPtr == NULL) { return NULL; } varPtr = (Var *) Tcl_GetHashValue(hPtr); if (varPtr->flags & VAR_UPVAR) { hPtr = varPtr->value.upvarPtr; varPtr = (Var *) Tcl_GetHashValue(hPtr); } if (name2 != NULL) { if (!(varPtr->flags & VAR_ARRAY)) { return NULL; } hPtr = Tcl_FindHashEntry(varPtr->value.tablePtr, name2); if (hPtr == NULL) { return NULL; } varPtr = (Var *) Tcl_GetHashValue(hPtr); } /* * Find the relevant trace, if any, and return its clientData. */ tracePtr = varPtr->tracePtr; if (prevClientData != NULL) { for ( ; tracePtr != NULL; tracePtr = tracePtr->nextPtr) { if ((tracePtr->clientData == prevClientData) && (tracePtr->traceProc == proc)) { tracePtr = tracePtr->nextPtr; break; } } } for ( ; tracePtr != NULL; tracePtr = tracePtr->nextPtr) { if (tracePtr->traceProc == proc) { return tracePtr->clientData; } } return NULL; } /* *---------------------------------------------------------------------- * * Tcl_SetCmd -- * * This procedure is invoked to process the "set" Tcl command. * See the user documentation for details on what it does. * * Results: * A standard Tcl result value. * * Side effects: * A variable's value may be changed. * *---------------------------------------------------------------------- */ /* ARGSUSED */ int Tcl_SetCmd(dummy, interp, argc, argv) ClientData dummy; /* Not used. */ register Tcl_Interp *interp; /* Current interpreter. */ int argc; /* Number of arguments. */ char **argv; /* Argument strings. */ { if (argc == 2) { char *value; value = Tcl_GetVar(interp, argv[1], TCL_LEAVE_ERR_MSG); if (value == NULL) { return TCL_ERROR; } interp->result = value; return TCL_OK; } else if (argc == 3) { char *result; result = Tcl_SetVar(interp, argv[1], argv[2], TCL_LEAVE_ERR_MSG); if (result == NULL) { return TCL_ERROR; } interp->result = result; return TCL_OK; } else { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " varName ?newValue?\"", (char *) NULL); return TCL_ERROR; } } /* *---------------------------------------------------------------------- * * Tcl_UnsetCmd -- * * This procedure is invoked to process the "unset" Tcl command. * See the user documentation for details on what it does. * * Results: * A standard Tcl result value. * * Side effects: * See the user documentation. * *---------------------------------------------------------------------- */ /* ARGSUSED */ int Tcl_UnsetCmd(dummy, interp, argc, argv) ClientData dummy; /* Not used. */ register Tcl_Interp *interp; /* Current interpreter. */ int argc; /* Number of arguments. */ char **argv; /* Argument strings. */ { int i; if (argc < 2) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " varName ?varName ...?\"", (char *) NULL); return TCL_ERROR; } for (i = 1; i < argc; i++) { if (Tcl_UnsetVar(interp, argv[i], TCL_LEAVE_ERR_MSG) != 0) { return TCL_ERROR; } } return TCL_OK; } /* *---------------------------------------------------------------------- * * Tcl_AppendCmd -- * * This procedure is invoked to process the "append" Tcl command. * See the user documentation for details on what it does. * * Results: * A standard Tcl result value. * * Side effects: * A variable's value may be changed. * *---------------------------------------------------------------------- */ /* ARGSUSED */ int Tcl_AppendCmd(dummy, interp, argc, argv) ClientData dummy; /* Not used. */ register Tcl_Interp *interp; /* Current interpreter. */ int argc; /* Number of arguments. */ char **argv; /* Argument strings. */ { int i; char *result = NULL; /* (Initialization only needed to keep * the compiler from complaining) */ if (argc < 3) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " varName value ?value ...?\"", (char *) NULL); return TCL_ERROR; } for (i = 2; i < argc; i++) { result = Tcl_SetVar(interp, argv[1], argv[i], TCL_APPEND_VALUE|TCL_LEAVE_ERR_MSG); if (result == NULL) { return TCL_ERROR; } } interp->result = result; return TCL_OK; } /* *---------------------------------------------------------------------- * * Tcl_LappendCmd -- * * This procedure is invoked to process the "lappend" Tcl command. * See the user documentation for details on what it does. * * Results: * A standard Tcl result value. * * Side effects: * A variable's value may be changed. * *---------------------------------------------------------------------- */ /* ARGSUSED */ int Tcl_LappendCmd(dummy, interp, argc, argv) ClientData dummy; /* Not used. */ register Tcl_Interp *interp; /* Current interpreter. */ int argc; /* Number of arguments. */ char **argv; /* Argument strings. */ { int i; char *result = NULL; /* (Initialization only needed to keep * the compiler from complaining) */ if (argc < 3) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " varName value ?value ...?\"", (char *) NULL); return TCL_ERROR; } for (i = 2; i < argc; i++) { result = Tcl_SetVar(interp, argv[1], argv[i], TCL_APPEND_VALUE|TCL_LIST_ELEMENT|TCL_LEAVE_ERR_MSG); if (result == NULL) { return TCL_ERROR; } } interp->result = result; return TCL_OK; } /* *---------------------------------------------------------------------- * * Tcl_ArrayCmd -- * * This procedure is invoked to process the "array" Tcl command. * See the user documentation for details on what it does. * * Results: * A standard Tcl result value. * * Side effects: * See the user documentation. * *---------------------------------------------------------------------- */ /* ARGSUSED */ int Tcl_ArrayCmd(dummy, interp, argc, argv) ClientData dummy; /* Not used. */ register Tcl_Interp *interp; /* Current interpreter. */ int argc; /* Number of arguments. */ char **argv; /* Argument strings. */ { int length; char c; Var *varPtr; Tcl_HashEntry *hPtr; Interp *iPtr = (Interp *) interp; if (argc < 3) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " option arrayName ?arg ...?\"", (char *) NULL); return TCL_ERROR; } /* * Locate the array variable (and it better be an array). */ if (iPtr->varFramePtr == NULL) { hPtr = Tcl_FindHashEntry(&iPtr->globalTable, argv[2]); } else { hPtr = Tcl_FindHashEntry(&iPtr->varFramePtr->varTable, argv[2]); } if (hPtr == NULL) { notArray: Tcl_AppendResult(interp, "\"", argv[2], "\" isn't an array", (char *) NULL); return TCL_ERROR; } varPtr = (Var *) Tcl_GetHashValue(hPtr); if (varPtr->flags & VAR_UPVAR) { varPtr = (Var *) Tcl_GetHashValue(varPtr->value.upvarPtr); } if (!(varPtr->flags & VAR_ARRAY)) { goto notArray; } /* * Dispatch based on the option. */ c = argv[1][0]; length = strlen(argv[1]); if ((c == 'a') && (strncmp(argv[1], "anymore", length) == 0)) { ArraySearch *searchPtr; if (argc != 4) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " anymore arrayName searchId\"", (char *) NULL); return TCL_ERROR; } searchPtr = ParseSearchId(interp, varPtr, argv[2], argv[3]); if (searchPtr == NULL) { return TCL_ERROR; } while (1) { Var *varPtr2; if (searchPtr->nextEntry != NULL) { varPtr2 = (Var *) Tcl_GetHashValue(searchPtr->nextEntry); if (!(varPtr2->flags & VAR_UNDEFINED)) { break; } } searchPtr->nextEntry = Tcl_NextHashEntry(&searchPtr->search); if (searchPtr->nextEntry == NULL) { interp->result = "0"; return TCL_OK; } } interp->result = "1"; return TCL_OK; } else if ((c == 'd') && (strncmp(argv[1], "donesearch", length) == 0)) { ArraySearch *searchPtr, *prevPtr; if (argc != 4) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " donesearch arrayName searchId\"", (char *) NULL); return TCL_ERROR; } searchPtr = ParseSearchId(interp, varPtr, argv[2], argv[3]); if (searchPtr == NULL) { return TCL_ERROR; } if (varPtr->searchPtr == searchPtr) { varPtr->searchPtr = searchPtr->nextPtr; } else { for (prevPtr = varPtr->searchPtr; ; prevPtr = prevPtr->nextPtr) { if (prevPtr->nextPtr == searchPtr) { prevPtr->nextPtr = searchPtr->nextPtr; break; } } } ckfree((char *) searchPtr); } else if ((c == 'n') && (strncmp(argv[1], "names", length) == 0) && (length >= 2)) { Tcl_HashSearch search; Var *varPtr2; if (argc != 3) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " names arrayName\"", (char *) NULL); return TCL_ERROR; } for (hPtr = Tcl_FirstHashEntry(varPtr->value.tablePtr, &search); hPtr != NULL; hPtr = Tcl_NextHashEntry(&search)) { varPtr2 = (Var *) Tcl_GetHashValue(hPtr); if (varPtr2->flags & VAR_UNDEFINED) { continue; } Tcl_AppendElement(interp, Tcl_GetHashKey(varPtr->value.tablePtr, hPtr), 0); } } else if ((c == 'n') && (strncmp(argv[1], "nextelement", length) == 0) && (length >= 2)) { ArraySearch *searchPtr; Tcl_HashEntry *hPtr; if (argc != 4) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " nextelement arrayName searchId\"", (char *) NULL); return TCL_ERROR; } searchPtr = ParseSearchId(interp, varPtr, argv[2], argv[3]); if (searchPtr == NULL) { return TCL_ERROR; } while (1) { Var *varPtr2; hPtr = searchPtr->nextEntry; if (hPtr == NULL) { hPtr = Tcl_NextHashEntry(&searchPtr->search); if (hPtr == NULL) { return TCL_OK; } } else { searchPtr->nextEntry = NULL; } varPtr2 = (Var *) Tcl_GetHashValue(hPtr); if (!(varPtr2->flags & VAR_UNDEFINED)) { break; } } interp->result = Tcl_GetHashKey(varPtr->value.tablePtr, hPtr); } else if ((c == 's') && (strncmp(argv[1], "size", length) == 0) && (length >= 2)) { Tcl_HashSearch search; Var *varPtr2; int size; if (argc != 3) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " size arrayName\"", (char *) NULL); return TCL_ERROR; } size = 0; for (hPtr = Tcl_FirstHashEntry(varPtr->value.tablePtr, &search); hPtr != NULL; hPtr = Tcl_NextHashEntry(&search)) { varPtr2 = (Var *) Tcl_GetHashValue(hPtr); if (varPtr2->flags & VAR_UNDEFINED) { continue; } size++; } sprintf(interp->result, "%d", size); } else if ((c == 's') && (strncmp(argv[1], "startsearch", length) == 0) && (length >= 2)) { ArraySearch *searchPtr; if (argc != 3) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " startsearch arrayName\"", (char *) NULL); return TCL_ERROR; } searchPtr = (ArraySearch *) ckalloc(sizeof(ArraySearch)); if (varPtr->searchPtr == NULL) { searchPtr->id = 1; Tcl_AppendResult(interp, "s-1-", argv[2], (char *) NULL); } else { char string[20]; searchPtr->id = varPtr->searchPtr->id + 1; sprintf(string, "%d", searchPtr->id); Tcl_AppendResult(interp, "s-", string, "-", argv[2], (char *) NULL); } searchPtr->varPtr = varPtr; searchPtr->nextEntry = Tcl_FirstHashEntry(varPtr->value.tablePtr, &searchPtr->search); searchPtr->nextPtr = varPtr->searchPtr; varPtr->searchPtr = searchPtr; } else { Tcl_AppendResult(interp, "bad option \"", argv[1], "\": should be anymore, donesearch, names, nextelement, ", "size, or startsearch", (char *) NULL); return TCL_ERROR; } return TCL_OK; } /* *---------------------------------------------------------------------- * * Tcl_GlobalCmd -- * * This procedure is invoked to process the "global" Tcl command. * See the user documentation for details on what it does. * * Results: * A standard Tcl result value. * * Side effects: * See the user documentation. * *---------------------------------------------------------------------- */ /* ARGSUSED */ int Tcl_GlobalCmd(dummy, interp, argc, argv) ClientData dummy; /* Not used. */ Tcl_Interp *interp; /* Current interpreter. */ int argc; /* Number of arguments. */ char **argv; /* Argument strings. */ { Var *varPtr, *gVarPtr; register Interp *iPtr = (Interp *) interp; Tcl_HashEntry *hPtr, *hPtr2; int new; if (argc < 2) { Tcl_AppendResult((Tcl_Interp *) iPtr, "wrong # args: should be \"", argv[0], " varName ?varName ...?\"", (char *) NULL); return TCL_ERROR; } if (iPtr->varFramePtr == NULL) { return TCL_OK; } for (argc--, argv++; argc > 0; argc--, argv++) { hPtr = Tcl_CreateHashEntry(&iPtr->globalTable, *argv, &new); if (new) { gVarPtr = NewVar(0); gVarPtr->flags |= VAR_UNDEFINED; Tcl_SetHashValue(hPtr, gVarPtr); } else { gVarPtr = (Var *) Tcl_GetHashValue(hPtr); } hPtr2 = Tcl_CreateHashEntry(&iPtr->varFramePtr->varTable, *argv, &new); if (!new) { Var *varPtr; varPtr = (Var *) Tcl_GetHashValue(hPtr2); if (varPtr->flags & VAR_UPVAR) { continue; } else { Tcl_AppendResult((Tcl_Interp *) iPtr, "variable \"", *argv, "\" already exists", (char *) NULL); return TCL_ERROR; } } varPtr = NewVar(0); varPtr->flags |= VAR_UPVAR; varPtr->value.upvarPtr = hPtr; gVarPtr->upvarUses++; Tcl_SetHashValue(hPtr2, varPtr); } return TCL_OK; } /* *---------------------------------------------------------------------- * * Tcl_UpvarCmd -- * * This procedure is invoked to process the "upvar" Tcl command. * See the user documentation for details on what it does. * * Results: * A standard Tcl result value. * * Side effects: * See the user documentation. * *---------------------------------------------------------------------- */ /* ARGSUSED */ int Tcl_UpvarCmd(dummy, interp, argc, argv) ClientData dummy; /* Not used. */ Tcl_Interp *interp; /* Current interpreter. */ int argc; /* Number of arguments. */ char **argv; /* Argument strings. */ { register Interp *iPtr = (Interp *) interp; int result; CallFrame *framePtr; Var *varPtr = NULL; Tcl_HashTable *upVarTablePtr; Tcl_HashEntry *hPtr, *hPtr2; int new; Var *upVarPtr; if (argc < 3) { upvarSyntax: Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " ?level? otherVar localVar ?otherVar localVar ...?\"", (char *) NULL); return TCL_ERROR; } /* * Find the hash table containing the variable being referenced. */ result = TclGetFrame(interp, argv[1], &framePtr); if (result == -1) { return TCL_ERROR; } argc -= result+1; argv += result+1; if (framePtr == NULL) { upVarTablePtr = &iPtr->globalTable; } else { upVarTablePtr = &framePtr->varTable; } if ((argc & 1) != 0) { goto upvarSyntax; } /* * Iterate over all the pairs of (local variable, other variable) * names. For each pair, create a hash table entry in the upper * context (if the name wasn't there already), then associate it * with a new local variable. */ while (argc > 0) { hPtr = Tcl_CreateHashEntry(upVarTablePtr, argv[0], &new); if (new) { upVarPtr = NewVar(0); upVarPtr->flags |= VAR_UNDEFINED; Tcl_SetHashValue(hPtr, upVarPtr); } else { upVarPtr = (Var *) Tcl_GetHashValue(hPtr); if (upVarPtr->flags & VAR_UPVAR) { hPtr = upVarPtr->value.upvarPtr; upVarPtr = (Var *) Tcl_GetHashValue(hPtr); } } hPtr2 = Tcl_CreateHashEntry(&iPtr->varFramePtr->varTable, argv[1], &new); if (!new) { Tcl_AppendResult((Tcl_Interp *) iPtr, "variable \"", argv[1], "\" already exists", (char *) NULL); return TCL_ERROR; } varPtr = NewVar(0); varPtr->flags |= VAR_UPVAR; varPtr->value.upvarPtr = hPtr; upVarPtr->upvarUses++; Tcl_SetHashValue(hPtr2, varPtr); argc -= 2; argv += 2; } return TCL_OK; } /* *---------------------------------------------------------------------- * * TclDeleteVars -- * * This procedure is called to recycle all the storage space * associated with a table of variables. For this procedure * to work correctly, it must not be possible for any of the * variable in the table to be accessed from Tcl commands * (e.g. from trace procedures). * * Results: * None. * * Side effects: * Variables are deleted and trace procedures are invoked, if * any are declared. * *---------------------------------------------------------------------- */ void TclDeleteVars(iPtr, tablePtr) Interp *iPtr; /* Interpreter to which variables belong. */ Tcl_HashTable *tablePtr; /* Hash table containing variables to * delete. */ { Tcl_HashSearch search; Tcl_HashEntry *hPtr; register Var *varPtr; int flags, globalFlag; flags = TCL_TRACE_UNSETS; if (tablePtr == &iPtr->globalTable) { flags |= TCL_INTERP_DESTROYED | TCL_GLOBAL_ONLY; } for (hPtr = Tcl_FirstHashEntry(tablePtr, &search); hPtr != NULL; hPtr = Tcl_NextHashEntry(&search)) { varPtr = (Var *) Tcl_GetHashValue(hPtr); /* * For global/upvar variables referenced in procedures, free up the * local space and then decrement the reference count on the * variable referred to. If there are no more references to the * global/upvar and it is undefined and has no traces set, then * follow on and delete the referenced variable too. */ globalFlag = 0; if (varPtr->flags & VAR_UPVAR) { hPtr = varPtr->value.upvarPtr; ckfree((char *) varPtr); varPtr = (Var *) Tcl_GetHashValue(hPtr); varPtr->upvarUses--; if ((varPtr->upvarUses != 0) || !(varPtr->flags & VAR_UNDEFINED) || (varPtr->tracePtr != NULL)) { continue; } globalFlag = TCL_GLOBAL_ONLY; } /* * Invoke traces on the variable that is being deleted, then * free up the variable's space (no need to free the hash entry * here, unless we're dealing with a global variable: the * hash entries will be deleted automatically when the whole * table is deleted). */ if (varPtr->tracePtr != NULL) { (void) CallTraces(iPtr, (Var *) NULL, hPtr, Tcl_GetHashKey(tablePtr, hPtr), (char *) NULL, flags | globalFlag); while (varPtr->tracePtr != NULL) { VarTrace *tracePtr = varPtr->tracePtr; varPtr->tracePtr = tracePtr->nextPtr; ckfree((char *) tracePtr); } } if (varPtr->flags & VAR_ARRAY) { DeleteArray(iPtr, Tcl_GetHashKey(tablePtr, hPtr), varPtr, flags | globalFlag); } if (globalFlag) { Tcl_DeleteHashEntry(hPtr); } ckfree((char *) varPtr); } Tcl_DeleteHashTable(tablePtr); } /* *---------------------------------------------------------------------- * * CallTraces -- * * This procedure is invoked to find and invoke relevant * trace procedures associated with a particular operation on * a variable. This procedure invokes traces both on the * variable and on its containing array (where relevant). * * Results: * The return value is NULL if no trace procedures were invoked, or * if all the invoked trace procedures returned successfully. * The return value is non-zero if a trace procedure returned an * error (in this case no more trace procedures were invoked after * the error was returned). In this case the return value is a * pointer to a static string describing the error. * * Side effects: * Almost anything can happen, depending on trace; this procedure * itself doesn't have any side effects. * *---------------------------------------------------------------------- */ static char * CallTraces(iPtr, arrayPtr, hPtr, name1, name2, flags) Interp *iPtr; /* Interpreter containing variable. */ register Var *arrayPtr; /* Pointer to array variable that * contains the variable, or NULL if * the variable isn't an element of an * array. */ Tcl_HashEntry *hPtr; /* Hash table entry corresponding to * variable whose traces are to be * invoked. */ char *name1, *name2; /* Variable's two-part name. */ int flags; /* Flags to pass to trace procedures: * indicates what's happening to * variable, plus other stuff like * TCL_GLOBAL_ONLY and * TCL_INTERP_DESTROYED. */ { Var *varPtr; register VarTrace *tracePtr; ActiveVarTrace active; char *result; int savedArrayFlags = 0; /* (Initialization not needed except * to prevent compiler warning) */ /* * If there are already similar trace procedures active for the * variable, don't call them again. */ varPtr = (Var *) Tcl_GetHashValue(hPtr); if (varPtr->flags & VAR_TRACE_ACTIVE) { return NULL; } varPtr->flags |= VAR_TRACE_ACTIVE; /* * Invoke traces on the array containing the variable, if relevant. */ result = NULL; active.nextPtr = iPtr->activeTracePtr; iPtr->activeTracePtr = &active; if (arrayPtr != NULL) { savedArrayFlags = arrayPtr->flags; arrayPtr->flags |= VAR_ELEMENT_ACTIVE; for (tracePtr = arrayPtr->tracePtr; tracePtr != NULL; tracePtr = active.nextTracePtr) { active.nextTracePtr = tracePtr->nextPtr; if (!(tracePtr->flags & flags)) { continue; } result = (*tracePtr->traceProc)(tracePtr->clientData, (Tcl_Interp *) iPtr, name1, name2, flags); if (result != NULL) { if (flags & TCL_TRACE_UNSETS) { result = NULL; } else { goto done; } } } } /* * Invoke traces on the variable itself. */ if (flags & TCL_TRACE_UNSETS) { flags |= TCL_TRACE_DESTROYED; } for (tracePtr = varPtr->tracePtr; tracePtr != NULL; tracePtr = active.nextTracePtr) { active.nextTracePtr = tracePtr->nextPtr; if (!(tracePtr->flags & flags)) { continue; } result = (*tracePtr->traceProc)(tracePtr->clientData, (Tcl_Interp *) iPtr, name1, name2, flags); if (result != NULL) { if (flags & TCL_TRACE_UNSETS) { result = NULL; } else { goto done; } } } /* * Restore the variable's flags, remove the record of our active * traces, and then return. Remember that the variable could have * been re-allocated during the traces, but its hash entry won't * change. */ done: if (arrayPtr != NULL) { arrayPtr->flags = savedArrayFlags; } varPtr = (Var *) Tcl_GetHashValue(hPtr); varPtr->flags &= ~VAR_TRACE_ACTIVE; iPtr->activeTracePtr = active.nextPtr; return result; } /* *---------------------------------------------------------------------- * * NewVar -- * * Create a new variable with a given initial value. * * Results: * The return value is a pointer to the new variable structure. * The variable will not be part of any hash table yet, and its * upvarUses count is initialized to 0. Its initial value will * be empty, but "space" bytes will be available in the value * area. * * Side effects: * Storage gets allocated. * *---------------------------------------------------------------------- */ static Var * NewVar(space) int space; /* Minimum amount of space to allocate * for variable's value. */ { int extra; register Var *varPtr; extra = space - sizeof(varPtr->value); if (extra < 0) { extra = 0; space = sizeof(varPtr->value); } varPtr = (Var *) ckalloc((unsigned) (sizeof(Var) + extra)); varPtr->valueLength = 0; varPtr->valueSpace = space; varPtr->upvarUses = 0; varPtr->tracePtr = NULL; varPtr->searchPtr = NULL; varPtr->flags = 0; varPtr->value.string[0] = 0; return varPtr; } /* *---------------------------------------------------------------------- * * ParseSearchId -- * * This procedure translates from a string to a pointer to an * active array search (if there is one that matches the string). * * Results: * The return value is a pointer to the array search indicated * by string, or NULL if there isn't one. If NULL is returned, * interp->result contains an error message. * * Side effects: * None. * *---------------------------------------------------------------------- */ static ArraySearch * ParseSearchId(interp, varPtr, varName, string) Tcl_Interp *interp; /* Interpreter containing variable. */ Var *varPtr; /* Array variable search is for. */ char *varName; /* Name of array variable that search is * supposed to be for. */ char *string; /* String containing id of search. Must have * form "search-num-var" where "num" is a * decimal number and "var" is a variable * name. */ { char *end; int id; ArraySearch *searchPtr; /* * Parse the id into the three parts separated by dashes. */ if ((string[0] != 's') || (string[1] != '-')) { syntax: Tcl_AppendResult(interp, "illegal search identifier \"", string, "\"", (char *) NULL); return NULL; } id = strtoul(string+2, &end, 10); if ((end == (string+2)) || (*end != '-')) { goto syntax; } if (strcmp(end+1, varName) != 0) { Tcl_AppendResult(interp, "search identifier \"", string, "\" isn't for variable \"", varName, "\"", (char *) NULL); return NULL; } /* * Search through the list of active searches on the interpreter * to see if the desired one exists. */ for (searchPtr = varPtr->searchPtr; searchPtr != NULL; searchPtr = searchPtr->nextPtr) { if (searchPtr->id == id) { return searchPtr; } } Tcl_AppendResult(interp, "couldn't find search \"", string, "\"", (char *) NULL); return NULL; } /* *---------------------------------------------------------------------- * * DeleteSearches -- * * This procedure is called to free up all of the searches * associated with an array variable. * * Results: * None. * * Side effects: * Memory is released to the storage allocator. * *---------------------------------------------------------------------- */ static void DeleteSearches(arrayVarPtr) register Var *arrayVarPtr; /* Variable whose searches are * to be deleted. */ { ArraySearch *searchPtr; while (arrayVarPtr->searchPtr != NULL) { searchPtr = arrayVarPtr->searchPtr; arrayVarPtr->searchPtr = searchPtr->nextPtr; ckfree((char *) searchPtr); } } /* *---------------------------------------------------------------------- * * DeleteArray -- * * This procedure is called to free up everything in an array * variable. It's the caller's responsibility to make sure * that the array is no longer accessible before this procedure * is called. * * Results: * None. * * Side effects: * All storage associated with varPtr's array elements is deleted * (including the hash table). Any delete trace procedures for * array elements are invoked. * *---------------------------------------------------------------------- */ static void DeleteArray(iPtr, arrayName, varPtr, flags) Interp *iPtr; /* Interpreter containing array. */ char *arrayName; /* Name of array (used for trace * callbacks). */ Var *varPtr; /* Pointer to variable structure. */ int flags; /* Flags to pass to CallTraces: * TCL_TRACE_UNSETS and sometimes * TCL_INTERP_DESTROYED and/or * TCL_GLOBAL_ONLY. */ { Tcl_HashSearch search; register Tcl_HashEntry *hPtr; register Var *elPtr; DeleteSearches(varPtr); for (hPtr = Tcl_FirstHashEntry(varPtr->value.tablePtr, &search); hPtr != NULL; hPtr = Tcl_NextHashEntry(&search)) { elPtr = (Var *) Tcl_GetHashValue(hPtr); if (elPtr->tracePtr != NULL) { (void) CallTraces(iPtr, (Var *) NULL, hPtr, arrayName, Tcl_GetHashKey(varPtr->value.tablePtr, hPtr), flags); while (elPtr->tracePtr != NULL) { VarTrace *tracePtr = elPtr->tracePtr; elPtr->tracePtr = tracePtr->nextPtr; ckfree((char *) tracePtr); } } if (elPtr->flags & VAR_SEARCHES_POSSIBLE) { panic("DeleteArray found searches on array alement!"); } ckfree((char *) elPtr); } Tcl_DeleteHashTable(varPtr->value.tablePtr); ckfree((char *) varPtr->value.tablePtr); } /* *---------------------------------------------------------------------- * * VarErrMsg -- * * Generate a reasonable error message describing why a variable * operation failed. * * Results: * None. * * Side effects: * Interp->result is reset to hold a message identifying the * variable given by name1 and name2 and describing why the * variable operation failed. * *---------------------------------------------------------------------- */ static void VarErrMsg(interp, name1, name2, operation, reason) Tcl_Interp *interp; /* Interpreter in which to record message. */ char *name1, *name2; /* Variable's two-part name. */ char *operation; /* String describing operation that failed, * e.g. "read", "set", or "unset". */ char *reason; /* String describing why operation failed. */ { Tcl_ResetResult(interp); Tcl_AppendResult(interp, "can't ", operation, " \"", name1, (char *) NULL); if (name2 != NULL) { Tcl_AppendResult(interp, "(", name2, ")", (char *) NULL); } Tcl_AppendResult(interp, "\": ", reason, (char *) NULL); }