freebsd-nq/contrib/tcl/generic/tclVar.c
1997-11-27 19:49:05 +00:00

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/*
* 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 Mark Diekhans and Karl Lehenbauer.
*
* Copyright (c) 1987-1994 The Regents of the University of California.
* Copyright (c) 1994-1997 Sun Microsystems, Inc.
*
* See the file "license.terms" for information on usage and redistribution
* of this file, and for a DISCLAIMER OF ALL WARRANTIES.
*
* SCCS: @(#) tclVar.c 1.130 97/10/29 18:26:16
*/
#include "tclInt.h"
#include "tclPort.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 *danglingUpvar = "upvar refers to element in deleted array";
static char *badNamespace = "parent namespace doesn't exist";
static char *missingName = "missing variable name";
/*
* Forward references to procedures defined later in this file:
*/
static char * CallTraces _ANSI_ARGS_((Interp *iPtr, Var *arrayPtr,
Var *varPtr, char *part1, char *part2,
int flags));
static void CleanupVar _ANSI_ARGS_((Var *varPtr,
Var *arrayPtr));
static void DeleteSearches _ANSI_ARGS_((Var *arrayVarPtr));
static void DeleteArray _ANSI_ARGS_((Interp *iPtr,
char *arrayName, Var *varPtr, int flags));
static int MakeUpvar _ANSI_ARGS_((
Interp *iPtr, CallFrame *framePtr,
char *otherP1, char *otherP2, int otherFlags,
char *myName, int myFlags));
static Var * NewVar _ANSI_ARGS_((void));
static ArraySearch * ParseSearchId _ANSI_ARGS_((Tcl_Interp *interp,
Var *varPtr, char *varName, char *string));
static void VarErrMsg _ANSI_ARGS_((Tcl_Interp *interp,
char *part1, char *part2, char *operation,
char *reason));
/*
*----------------------------------------------------------------------
*
* TclLookupVar --
*
* This procedure is used by virtually all of the variable code to
* locate a variable given its name(s).
*
* Results:
* The return value is a pointer to the variable structure indicated by
* part1 and part2, or NULL if the variable couldn't be found. If the
* variable is found, *arrayPtrPtr is filled in with the address of the
* variable structure for the array that contains the variable (or NULL
* if the variable is a scalar). If the variable can't be found and
* either createPart1 or createPart2 are 1, a new as-yet-undefined
* (VAR_UNDEFINED) variable structure is created, entered into a hash
* table, and returned.
*
* If the variable isn't found and creation wasn't specified, or some
* other error occurs, NULL is returned and an error message is left in
* interp->result if TCL_LEAVE_ERR_MSG is set in flags. (The result
* isn't put in interp->objResultPtr because this procedure is used
* by so many string-based routines.)
*
* Note: it's possible for the variable returned to be VAR_UNDEFINED
* even if createPart1 or createPart2 are 1 (these only cause the hash
* table entry or array to be created). For example, the variable might
* be a global that has been unset but is still referenced by a
* procedure, or a variable that has been unset but it only being kept
* in existence (if VAR_UNDEFINED) by a trace.
*
* Side effects:
* New hashtable entries may be created if createPart1 or createPart2
* are 1.
*
*----------------------------------------------------------------------
*/
Var *
TclLookupVar(interp, part1, part2, flags, msg, createPart1, createPart2,
arrayPtrPtr)
Tcl_Interp *interp; /* Interpreter to use for lookup. */
char *part1; /* If part2 isn't NULL, this is the name of
* an array. Otherwise, if the
* TCL_PARSE_PART1 flag bit is set this
* is a full variable name that could
* include a parenthesized array elemnt. If
* TCL_PARSE_PART1 isn't present, then
* this is the name of a scalar variable. */
char *part2; /* Name of element within array, or NULL. */
int flags; /* Only TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY,
* TCL_LEAVE_ERR_MSG, and
* TCL_PARSE_PART1 bits matter. */
char *msg; /* Verb to use in error messages, e.g.
* "read" or "set". Only needed if
* TCL_LEAVE_ERR_MSG is set in flags. */
int createPart1; /* If 1, create hash table entry for part 1
* of name, if it doesn't already exist. If
* 0, return error if it doesn't exist. */
int createPart2; /* If 1, create hash table entry for part 2
* of name, if it doesn't already exist. If
* 0, return error if it doesn't exist. */
Var **arrayPtrPtr; /* If the name refers to an element of an
* array, *arrayPtrPtr gets filled in with
* address of array variable. Otherwise
* this is set to NULL. */
{
Interp *iPtr = (Interp *) interp;
CallFrame *varFramePtr = iPtr->varFramePtr;
/* Points to the procedure call frame whose
* variables are currently in use. Same as
* the current procedure's frame, if any,
* unless an "uplevel" is executing. */
Tcl_HashTable *tablePtr; /* Points to the hashtable, if any, in which
* to look up the variable. */
Tcl_Var var; /* Used to search for global names. */
Var *varPtr; /* Points to the Var structure returned for
* the variable. */
char *elName; /* Name of array element or NULL; may be
* same as part2, or may be openParen+1. */
char *openParen, *closeParen;
/* If this procedure parses a name into
* array and index, these point to the
* parens around the index. Otherwise they
* are NULL. These are needed to restore
* the parens after parsing the name. */
Namespace *varNsPtr, *dummy1Ptr, *dummy2Ptr;
Tcl_HashEntry *hPtr;
register char *p;
int new, i, result;
varPtr = NULL;
*arrayPtrPtr = NULL;
openParen = closeParen = NULL;
varNsPtr = NULL; /* set non-NULL if a nonlocal variable */
/*
* If the name hasn't been parsed into array name and index yet,
* do it now.
*/
elName = part2;
if (flags & TCL_PARSE_PART1) {
for (p = part1; ; p++) {
if (*p == 0) {
elName = NULL;
break;
}
if (*p == '(') {
openParen = p;
do {
p++;
} while (*p != '\0');
p--;
if (*p == ')') {
closeParen = p;
*openParen = 0;
elName = openParen+1;
} else {
openParen = NULL;
elName = NULL;
}
break;
}
}
}
/*
* Look up part1. Look it up as either a namespace variable or as a
* local variable in a procedure call frame (varFramePtr).
* Interpret part1 as a namespace variable if:
* 1) so requested by a TCL_GLOBAL_ONLY or TCL_NAMESPACE_ONLY flag,
* 2) there is no active frame (we're at the global :: scope),
* 3) the active frame was pushed to define the namespace context
* for a "namespace eval" or "namespace inscope" command,
* 4) the name has namespace qualifiers ("::"s).
* Otherwise, if part1 is a local variable, search first in the
* frame's array of compiler-allocated local variables, then in its
* hashtable for runtime-created local variables.
*
* If createPart1 and the variable isn't found, create the variable and,
* if necessary, create varFramePtr's local var hashtable.
*/
if (((flags & (TCL_GLOBAL_ONLY | TCL_NAMESPACE_ONLY)) != 0)
|| (varFramePtr == NULL)
|| !varFramePtr->isProcCallFrame
|| (strstr(part1, "::") != NULL)) {
char *tail;
var = Tcl_FindNamespaceVar(interp, part1, (Tcl_Namespace *) NULL,
flags);
if (var != (Tcl_Var) NULL) {
varPtr = (Var *) var;
}
if (varPtr == NULL) {
if (flags & TCL_LEAVE_ERR_MSG) {
Tcl_ResetResult(interp);
}
if (createPart1) { /* var wasn't found so create it */
result = TclGetNamespaceForQualName(interp, part1,
(Namespace *) NULL, flags, &varNsPtr, &dummy1Ptr,
&dummy2Ptr, &tail);
if (result != TCL_OK) {
if (flags & TCL_LEAVE_ERR_MSG) {
/*
* Move the interpreter's object result to the
* string result, then reset the object result.
* FAILS IF OBJECT RESULT'S STRING REP HAS NULLS.
*/
Tcl_SetResult(interp,
TclGetStringFromObj(Tcl_GetObjResult(interp),
(int *) NULL),
TCL_VOLATILE);
}
goto done;
}
if (varNsPtr == NULL) {
if (flags & TCL_LEAVE_ERR_MSG) {
VarErrMsg(interp, part1, part2, msg, badNamespace);
}
goto done;
}
if (tail == NULL) {
if (flags & TCL_LEAVE_ERR_MSG) {
VarErrMsg(interp, part1, part2, msg, missingName);
}
goto done;
}
hPtr = Tcl_CreateHashEntry(&varNsPtr->varTable, tail, &new);
varPtr = NewVar();
Tcl_SetHashValue(hPtr, varPtr);
varPtr->hPtr = hPtr;
varPtr->nsPtr = varNsPtr;
} else { /* var wasn't found and not to create it */
if (flags & TCL_LEAVE_ERR_MSG) {
VarErrMsg(interp, part1, part2, msg, noSuchVar);
}
goto done;
}
}
} else { /* local var: look in frame varFramePtr */
Proc *procPtr = varFramePtr->procPtr;
int localCt = procPtr->numCompiledLocals;
CompiledLocal *localPtr = procPtr->firstLocalPtr;
Var *localVarPtr = varFramePtr->compiledLocals;
int part1Len = strlen(part1);
for (i = 0; i < localCt; i++) {
if (!localPtr->isTemp) {
char *localName = localVarPtr->name;
if ((part1[0] == localName[0])
&& (part1Len == localPtr->nameLength)
&& (strcmp(part1, localName) == 0)) {
varPtr = localVarPtr;
break;
}
}
localVarPtr++;
localPtr = localPtr->nextPtr;
}
if (varPtr == NULL) { /* look in the frame's var hash table */
tablePtr = varFramePtr->varTablePtr;
if (createPart1) {
if (tablePtr == NULL) {
tablePtr = (Tcl_HashTable *)
ckalloc(sizeof(Tcl_HashTable));
Tcl_InitHashTable(tablePtr, TCL_STRING_KEYS);
varFramePtr->varTablePtr = tablePtr;
}
hPtr = Tcl_CreateHashEntry(tablePtr, part1, &new);
if (new) {
varPtr = NewVar();
Tcl_SetHashValue(hPtr, varPtr);
varPtr->hPtr = hPtr;
varPtr->nsPtr = NULL; /* a local variable */
} else {
varPtr = (Var *) Tcl_GetHashValue(hPtr);
}
} else {
hPtr = NULL;
if (tablePtr != NULL) {
hPtr = Tcl_FindHashEntry(tablePtr, part1);
}
if (hPtr == NULL) {
if (flags & TCL_LEAVE_ERR_MSG) {
VarErrMsg(interp, part1, part2, msg, noSuchVar);
}
goto done;
}
varPtr = (Var *) Tcl_GetHashValue(hPtr);
}
}
}
if (openParen != NULL) {
*openParen = '(';
openParen = NULL;
}
/*
* If varPtr is a link variable, we have a reference to some variable
* that was created through an "upvar" or "global" command. Traverse
* through any links until we find the referenced variable.
*/
while (TclIsVarLink(varPtr)) {
varPtr = varPtr->value.linkPtr;
}
/*
* If we're not dealing with an array element, return varPtr.
*/
if (elName == NULL) {
goto done;
}
/*
* We're dealing with an array element. Make sure the variable is an
* array and look up the element (create the element if desired).
*/
if (TclIsVarUndefined(varPtr) && !TclIsVarArrayElement(varPtr)) {
if (!createPart1) {
if (flags & TCL_LEAVE_ERR_MSG) {
VarErrMsg(interp, part1, part2, msg, noSuchVar);
}
varPtr = NULL;
goto done;
}
TclSetVarArray(varPtr);
TclClearVarUndefined(varPtr);
varPtr->value.tablePtr =
(Tcl_HashTable *) ckalloc(sizeof(Tcl_HashTable));
Tcl_InitHashTable(varPtr->value.tablePtr, TCL_STRING_KEYS);
} else if (!TclIsVarArray(varPtr)) {
if (flags & TCL_LEAVE_ERR_MSG) {
VarErrMsg(interp, part1, part2, msg, needArray);
}
varPtr = NULL;
goto done;
}
*arrayPtrPtr = varPtr;
if (closeParen != NULL) {
*closeParen = 0;
}
if (createPart2) {
hPtr = Tcl_CreateHashEntry(varPtr->value.tablePtr, elName, &new);
if (closeParen != NULL) {
*closeParen = ')';
}
if (new) {
if (varPtr->searchPtr != NULL) {
DeleteSearches(varPtr);
}
varPtr = NewVar();
Tcl_SetHashValue(hPtr, varPtr);
varPtr->hPtr = hPtr;
varPtr->nsPtr = varNsPtr;
TclSetVarArrayElement(varPtr);
}
} else {
hPtr = Tcl_FindHashEntry(varPtr->value.tablePtr, elName);
if (closeParen != NULL) {
*closeParen = ')';
}
if (hPtr == NULL) {
if (flags & TCL_LEAVE_ERR_MSG) {
VarErrMsg(interp, part1, part2, msg, noSuchElement);
}
varPtr = NULL;
goto done;
}
}
varPtr = (Var *) Tcl_GetHashValue(hPtr);
done:
if (openParen != NULL) {
*openParen = '(';
}
return varPtr;
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetVar --
*
* Return the value of a Tcl variable as a string.
*
* Results:
* The return value points to the current value of varName as a string.
* 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 change to the
* variable; 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,
* TCL_NAMESPACE_ONLY or TCL_LEAVE_ERR_MSG
* bits. */
{
return Tcl_GetVar2(interp, varName, (char *) NULL,
(flags | TCL_PARSE_PART1));
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetVar2 --
*
* Return the value of a Tcl variable as a string, 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 part1 and part2 as a string. 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 change to the variable; if you depend on the value
* lasting longer than that, then make yourself a private copy.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
char *
Tcl_GetVar2(interp, part1, part2, flags)
Tcl_Interp *interp; /* Command interpreter in which variable is
* to be looked up. */
char *part1; /* Name of an array (if part2 is non-NULL)
* or the name of a variable. */
char *part2; /* If non-NULL, gives the name of an element
* in the array part1. */
int flags; /* OR-ed combination of TCL_GLOBAL_ONLY,
* TCL_NAMESPACE_ONLY, TCL_LEAVE_ERR_MSG,
* and TCL_PARSE_PART1 bits. */
{
register Tcl_Obj *part1Ptr;
register Tcl_Obj *part2Ptr = NULL;
Tcl_Obj *objPtr;
int length;
length = strlen(part1);
TclNewObj(part1Ptr);
TclInitStringRep(part1Ptr, part1, length);
Tcl_IncrRefCount(part1Ptr);
if (part2 != NULL) {
length = strlen(part2);
TclNewObj(part2Ptr);
TclInitStringRep(part2Ptr, part2, length);
Tcl_IncrRefCount(part2Ptr);
}
objPtr = Tcl_ObjGetVar2(interp, part1Ptr, part2Ptr, flags);
TclDecrRefCount(part1Ptr); /* done with the part1 name object */
if (part2Ptr != NULL) {
TclDecrRefCount(part2Ptr); /* and the part2 name object */
}
if (objPtr == NULL) {
/*
* Move the interpreter's object result to the string result,
* then reset the object result.
* FAILS IF OBJECT RESULT'S STRING REPRESENTATION CONTAINS NULLS.
*/
Tcl_SetResult(interp,
TclGetStringFromObj(Tcl_GetObjResult(interp), (int *) NULL),
TCL_VOLATILE);
return NULL;
}
/*
* THIS FAILS IF Tcl_ObjGetVar2's RESULT'S STRING REP HAS A NULL BYTE.
*/
return TclGetStringFromObj(objPtr, (int *) NULL);
}
/*
*----------------------------------------------------------------------
*
* Tcl_ObjGetVar2 --
*
* Return the value of a Tcl variable as a Tcl object, given a
* two-part name consisting of array name and element within array.
*
* Results:
* The return value points to the current object value of the variable
* given by part1Ptr and part2Ptr. 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 the interpreter's result if the
* TCL_LEAVE_ERR_MSG flag is set.
*
* Side effects:
* The ref count for the returned object is _not_ incremented to
* reflect the returned reference; if you want to keep a reference to
* the object you must increment its ref count yourself.
*
*----------------------------------------------------------------------
*/
Tcl_Obj *
Tcl_ObjGetVar2(interp, part1Ptr, part2Ptr, flags)
Tcl_Interp *interp; /* Command interpreter in which variable is
* to be looked up. */
register Tcl_Obj *part1Ptr; /* Points to an object holding the name of
* an array (if part2 is non-NULL) or the
* name of a variable. */
register Tcl_Obj *part2Ptr; /* If non-null, points to an object holding
* the name of an element in the array
* part1Ptr. */
int flags; /* OR-ed combination of TCL_GLOBAL_ONLY,
* TCL_LEAVE_ERR_MSG, and
* TCL_PARSE_PART1 bits. */
{
Interp *iPtr = (Interp *) interp;
register Var *varPtr;
Var *arrayPtr;
char *part1, *msg;
char *part2 = NULL;
/*
* THIS FAILS IF A NAME OBJECT'S STRING REP HAS A NULL BYTE.
*/
part1 = TclGetStringFromObj(part1Ptr, (int *) NULL);
if (part2Ptr != NULL) {
part2 = TclGetStringFromObj(part2Ptr, (int *) NULL);
}
varPtr = TclLookupVar(interp, part1, part2, flags, "read",
/*createPart1*/ 0, /*createPart2*/ 1, &arrayPtr);
if (varPtr == NULL) {
return NULL;
}
/*
* Invoke any traces that have been set for the variable.
*/
if ((varPtr->tracePtr != NULL)
|| ((arrayPtr != NULL) && (arrayPtr->tracePtr != NULL))) {
msg = CallTraces(iPtr, arrayPtr, varPtr, part1, part2,
(flags & (TCL_NAMESPACE_ONLY|TCL_GLOBAL_ONLY|TCL_PARSE_PART1)) | TCL_TRACE_READS);
if (msg != NULL) {
if (flags & TCL_LEAVE_ERR_MSG) {
VarErrMsg(interp, part1, part2, "read", msg);
}
goto errorReturn;
}
}
/*
* Return the element if it's an existing scalar variable.
*/
if (TclIsVarScalar(varPtr) && !TclIsVarUndefined(varPtr)) {
return varPtr->value.objPtr;
}
if (flags & TCL_LEAVE_ERR_MSG) {
if (TclIsVarUndefined(varPtr) && (arrayPtr != NULL)
&& !TclIsVarUndefined(arrayPtr)) {
msg = noSuchElement;
} else if (TclIsVarArray(varPtr)) {
msg = isArray;
} else {
msg = noSuchVar;
}
VarErrMsg(interp, part1, part2, "read", msg);
}
/*
* An error. If the variable doesn't exist anymore and no-one's using
* it, then free up the relevant structures and hash table entries.
*/
errorReturn:
if (TclIsVarUndefined(varPtr)) {
CleanupVar(varPtr, arrayPtr);
}
return NULL;
}
/*
*----------------------------------------------------------------------
*
* TclGetIndexedScalar --
*
* Return the Tcl object value of a local scalar variable in the active
* procedure, given its index in the procedure's array of compiler
* allocated local variables.
*
* Results:
* The return value points to the current object value of the variable
* given by localIndex. If the specified variable doesn't exist, or
* there is a clash in array usage, or an error occurs while executing
* variable traces, then NULL is returned and a message will be left in
* the interpreter's result if leaveErrorMsg is 1.
*
* Side effects:
* The ref count for the returned object is _not_ incremented to
* reflect the returned reference; if you want to keep a reference to
* the object you must increment its ref count yourself.
*
*----------------------------------------------------------------------
*/
Tcl_Obj *
TclGetIndexedScalar(interp, localIndex, leaveErrorMsg)
Tcl_Interp *interp; /* Command interpreter in which variable is
* to be looked up. */
int localIndex; /* Index of variable in procedure's array
* of local variables. */
int leaveErrorMsg; /* 1 if to leave an error message in
* interpreter's result on an error.
* Otherwise no error message is left. */
{
Interp *iPtr = (Interp *) interp;
CallFrame *varFramePtr = iPtr->varFramePtr;
/* Points to the procedure call frame whose
* variables are currently in use. Same as
* the current procedure's frame, if any,
* unless an "uplevel" is executing. */
Var *compiledLocals = varFramePtr->compiledLocals;
Var *varPtr; /* Points to the variable's in-frame Var
* structure. */
char *varName; /* Name of the local variable. */
char *msg;
#ifdef TCL_COMPILE_DEBUG
Proc *procPtr = varFramePtr->procPtr;
int localCt = procPtr->numCompiledLocals;
if (compiledLocals == NULL) {
fprintf(stderr, "\nTclGetIndexedScalar: can't get local %i in frame 0x%x, no compiled locals\n",
localIndex, (unsigned int) varFramePtr);
panic("TclGetIndexedScalar: no compiled locals in frame 0x%x",
(unsigned int) varFramePtr);
}
if ((localIndex < 0) || (localIndex >= localCt)) {
fprintf(stderr, "\nTclGetIndexedScalar: can't get local %i in frame 0x%x with %i locals\n",
localIndex, (unsigned int) varFramePtr, localCt);
panic("TclGetIndexedScalar: bad local index %i in frame 0x%x",
localIndex, (unsigned int) varFramePtr);
}
#endif /* TCL_COMPILE_DEBUG */
varPtr = &(compiledLocals[localIndex]);
varName = varPtr->name;
/*
* If varPtr is a link variable, we have a reference to some variable
* that was created through an "upvar" or "global" command, or we have a
* reference to a variable in an enclosing namespace. Traverse through
* any links until we find the referenced variable.
*/
while (TclIsVarLink(varPtr)) {
varPtr = varPtr->value.linkPtr;
}
/*
* Invoke any traces that have been set for the variable.
*/
if (varPtr->tracePtr != NULL) {
msg = CallTraces(iPtr, /*arrayPtr*/ NULL, varPtr, varName, NULL,
TCL_TRACE_READS);
if (msg != NULL) {
if (leaveErrorMsg) {
VarErrMsg(interp, varName, NULL, "read", msg);
}
return NULL;
}
}
/*
* Make sure we're dealing with a scalar variable and not an array, and
* that the variable exists (isn't undefined).
*/
if (!TclIsVarScalar(varPtr) || TclIsVarUndefined(varPtr)) {
if (leaveErrorMsg) {
if (TclIsVarArray(varPtr)) {
msg = isArray;
} else {
msg = noSuchVar;
}
VarErrMsg(interp, varName, NULL, "read", msg);
}
return NULL;
}
return varPtr->value.objPtr;
}
/*
*----------------------------------------------------------------------
*
* TclGetElementOfIndexedArray --
*
* Return the Tcl object value for an element in a local array
* variable. The element is named by the object elemPtr while the
* array is specified by its index in the active procedure's array
* of compiler allocated local variables.
*
* Results:
* The return value points to the current object value of the
* element. If the specified array or element doesn't exist, or there
* is a clash in array usage, or an error occurs while executing
* variable traces, then NULL is returned and a message will be left in
* the interpreter's result if leaveErrorMsg is 1.
*
* Side effects:
* The ref count for the returned object is _not_ incremented to
* reflect the returned reference; if you want to keep a reference to
* the object you must increment its ref count yourself.
*
*----------------------------------------------------------------------
*/
Tcl_Obj *
TclGetElementOfIndexedArray(interp, localIndex, elemPtr, leaveErrorMsg)
Tcl_Interp *interp; /* Command interpreter in which variable is
* to be looked up. */
int localIndex; /* Index of array variable in procedure's
* array of local variables. */
Tcl_Obj *elemPtr; /* Points to an object holding the name of
* an element to get in the array. */
int leaveErrorMsg; /* 1 if to leave an error message in
* the interpreter's result on an error.
* Otherwise no error message is left. */
{
Interp *iPtr = (Interp *) interp;
CallFrame *varFramePtr = iPtr->varFramePtr;
/* Points to the procedure call frame whose
* variables are currently in use. Same as
* the current procedure's frame, if any,
* unless an "uplevel" is executing. */
Var *compiledLocals = varFramePtr->compiledLocals;
Var *arrayPtr; /* Points to the array's in-frame Var
* structure. */
char *arrayName; /* Name of the local array. */
Tcl_HashEntry *hPtr;
Var *varPtr = NULL; /* Points to the element's Var structure
* that we return. Initialized to avoid
* compiler warning. */
char *elem, *msg;
int new;
#ifdef TCL_COMPILE_DEBUG
Proc *procPtr = varFramePtr->procPtr;
int localCt = procPtr->numCompiledLocals;
if (compiledLocals == NULL) {
fprintf(stderr, "\nTclGetElementOfIndexedArray: can't get element of local %i in frame 0x%x, no compiled locals\n",
localIndex, (unsigned int) varFramePtr);
panic("TclGetIndexedScalar: no compiled locals in frame 0x%x",
(unsigned int) varFramePtr);
}
if ((localIndex < 0) || (localIndex >= localCt)) {
fprintf(stderr, "\nTclGetIndexedScalar: can't get element of local %i in frame 0x%x with %i locals\n",
localIndex, (unsigned int) varFramePtr, localCt);
panic("TclGetElementOfIndexedArray: bad local index %i in frame 0x%x",
localIndex, (unsigned int) varFramePtr);
}
#endif /* TCL_COMPILE_DEBUG */
/*
* THIS FAILS IF THE ELEMENT NAME OBJECT'S STRING REP HAS A NULL BYTE.
*/
elem = Tcl_GetStringFromObj(elemPtr, (int *) NULL);
arrayPtr = &(compiledLocals[localIndex]);
arrayName = arrayPtr->name;
/*
* If arrayPtr is a link variable, we have a reference to some variable
* that was created through an "upvar" or "global" command, or we have a
* reference to a variable in an enclosing namespace. Traverse through
* any links until we find the referenced variable.
*/
while (TclIsVarLink(arrayPtr)) {
arrayPtr = arrayPtr->value.linkPtr;
}
/*
* Make sure we're dealing with an array and that the array variable
* exists (isn't undefined).
*/
if (!TclIsVarArray(arrayPtr) || TclIsVarUndefined(arrayPtr)) {
if (leaveErrorMsg) {
VarErrMsg(interp, arrayName, elem, "read", noSuchVar);
}
goto errorReturn;
}
/*
* Look up the element. Note that we must create the element (but leave
* it marked undefined) if it does not already exist. This allows a
* trace to create new array elements "on the fly" that did not exist
* before. A trace is always passed a variable for the array element. If
* the trace does not define the variable, it will be deleted below (at
* errorReturn) and an error returned.
*/
hPtr = Tcl_CreateHashEntry(arrayPtr->value.tablePtr, elem, &new);
if (new) {
if (arrayPtr->searchPtr != NULL) {
DeleteSearches(arrayPtr);
}
varPtr = NewVar();
Tcl_SetHashValue(hPtr, varPtr);
varPtr->hPtr = hPtr;
varPtr->nsPtr = varFramePtr->nsPtr;
TclSetVarArrayElement(varPtr);
} else {
varPtr = (Var *) Tcl_GetHashValue(hPtr);
}
/*
* Invoke any traces that have been set for the element variable.
*/
if ((varPtr->tracePtr != NULL)
|| ((arrayPtr != NULL) && (arrayPtr->tracePtr != NULL))) {
msg = CallTraces(iPtr, arrayPtr, varPtr, arrayName, elem,
TCL_TRACE_READS);
if (msg != NULL) {
if (leaveErrorMsg) {
VarErrMsg(interp, arrayName, elem, "read", msg);
}
goto errorReturn;
}
}
/*
* Return the element if it's an existing scalar variable.
*/
if (TclIsVarScalar(varPtr) && !TclIsVarUndefined(varPtr)) {
return varPtr->value.objPtr;
}
if (leaveErrorMsg) {
if (TclIsVarArray(varPtr)) {
msg = isArray;
} else {
msg = noSuchVar;
}
VarErrMsg(interp, arrayName, elem, "read", msg);
}
/*
* An error. If the variable doesn't exist anymore and no-one's using
* it, then free up the relevant structures and hash table entries.
*/
errorReturn:
if ((varPtr != NULL) && TclIsVarUndefined(varPtr)) {
CleanupVar(varPtr, NULL); /* the array is not in a hashtable */
}
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_GetVar2(interp, argv[1], (char *) NULL,
TCL_LEAVE_ERR_MSG|TCL_PARSE_PART1);
if (value == NULL) {
return TCL_ERROR;
}
Tcl_SetResult(interp, value, TCL_VOLATILE);
return TCL_OK;
} else if (argc == 3) {
char *result;
result = Tcl_SetVar2(interp, argv[1], (char *) NULL, argv[2],
TCL_LEAVE_ERR_MSG|TCL_PARSE_PART1);
if (result == NULL) {
return TCL_ERROR;
}
Tcl_SetResult(interp, result, TCL_VOLATILE);
return TCL_OK;
} else {
Tcl_AppendResult(interp, "wrong # args: should be \"",
argv[0], " varName ?newValue?\"", (char *) NULL);
return TCL_ERROR;
}
}
/*
*----------------------------------------------------------------------
*
* Tcl_SetVar --
*
* Change the value of a variable.
*
* Results:
* Returns a pointer to the malloc'ed string which is the character
* representation of the variable's new value. The caller must 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. Note that the
* returned string may not be the same as newValue; this is because
* variable traces may modify the variable's value.
*
* 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_NAMESPACE_ONLY, TCL_APPEND_VALUE,
* TCL_LIST_ELEMENT, TCL_LEAVE_ERR_MSG. */
{
return Tcl_SetVar2(interp, varName, (char *) NULL, newValue,
(flags | TCL_PARSE_PART1));
}
/*
*----------------------------------------------------------------------
*
* 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 which is the character
* representation of the variable's new value. The caller must 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. Note that the returned
* string may not be the same as newValue; this is because variable
* traces may modify the variable's value.
*
* 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, part1, part2, newValue, flags)
Tcl_Interp *interp; /* Command interpreter in which variable is
* to be looked up. */
char *part1; /* If part2 is NULL, this is name of scalar
* variable. Otherwise it is the name of
* an array. */
char *part2; /* Name of an element within an 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_NAMESPACE_ONLY, TCL_APPEND_VALUE,
* TCL_LIST_ELEMENT, TCL_LEAVE_ERR_MSG, or
* TCL_PARSE_PART1. */
{
register Tcl_Obj *valuePtr;
register Tcl_Obj *part1Ptr;
register Tcl_Obj *part2Ptr = NULL;
Tcl_Obj *varValuePtr;
int length;
/*
* Create an object holding the variable's new value and use
* Tcl_ObjSetVar2 to actually set the variable.
*/
length = newValue ? strlen(newValue) : 0;
TclNewObj(valuePtr);
TclInitStringRep(valuePtr, newValue, length);
Tcl_IncrRefCount(valuePtr);
length = strlen(part1) ;
TclNewObj(part1Ptr);
TclInitStringRep(part1Ptr, part1, length);
Tcl_IncrRefCount(part1Ptr);
if (part2 != NULL) {
length = strlen(part2);
TclNewObj(part2Ptr);
TclInitStringRep(part2Ptr, part2, length);
Tcl_IncrRefCount(part2Ptr);
}
varValuePtr = Tcl_ObjSetVar2(interp, part1Ptr, part2Ptr, valuePtr,
flags);
TclDecrRefCount(part1Ptr); /* done with the part1 name object */
if (part2Ptr != NULL) {
TclDecrRefCount(part2Ptr); /* and the part2 name object */
}
Tcl_DecrRefCount(valuePtr); /* done with the object */
if (varValuePtr == NULL) {
/*
* Move the interpreter's object result to the string result,
* then reset the object result.
* FAILS IF OBJECT RESULT'S STRING REPRESENTATION CONTAINS NULLS.
*/
Tcl_SetResult(interp,
TclGetStringFromObj(Tcl_GetObjResult(interp), (int *) NULL),
TCL_VOLATILE);
return NULL;
}
/*
* THIS FAILS IF Tcl_ObjSetVar2's RESULT'S STRING REP HAS A NULL BYTE.
*/
return TclGetStringFromObj(varValuePtr, (int *) NULL);
}
/*
*----------------------------------------------------------------------
*
* Tcl_ObjSetVar2 --
*
* 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
* to a new Tcl object value. If the named scalar or array or element
* doesn't exist then create one.
*
* Results:
* Returns a pointer to the Tcl_Obj holding the new value of the
* variable. 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 the interpreter's result. Note that the returned object
* may not be the same one referenced by newValuePtr; this is because
* variable traces may modify the variable's value.
*
* Side effects:
* The value of the given variable is set. If either the array or the
* entry didn't exist then a new variable is created.
*
* The reference count is decremented for any old value of the variable
* and incremented for its new value. If the new value for the variable
* is not the same one referenced by newValuePtr (perhaps as a result
* of a variable trace), then newValuePtr's ref count is left unchanged
* by Tcl_ObjSetVar2. newValuePtr's ref count is also left unchanged if
* we are appending it as a string value: that is, if "flags" includes
* TCL_APPEND_VALUE but not TCL_LIST_ELEMENT.
*
* The reference count for the returned object is _not_ incremented: if
* you want to keep a reference to the object you must increment its
* ref count yourself.
*
*----------------------------------------------------------------------
*/
Tcl_Obj *
Tcl_ObjSetVar2(interp, part1Ptr, part2Ptr, newValuePtr, flags)
Tcl_Interp *interp; /* Command interpreter in which variable is
* to be found. */
register Tcl_Obj *part1Ptr; /* Points to an object holding the name of
* an array (if part2 is non-NULL) or the
* name of a variable. */
register Tcl_Obj *part2Ptr; /* If non-null, points to an object holding
* the name of an element in the array
* part1Ptr. */
Tcl_Obj *newValuePtr; /* New value for variable. */
int flags; /* Various flags that tell how to set value:
* any of TCL_GLOBAL_ONLY,
* TCL_NAMESPACE_ONLY, TCL_APPEND_VALUE,
* TCL_LIST_ELEMENT, TCL_LEAVE_ERR_MSG, or
* TCL_PARSE_PART1. */
{
Interp *iPtr = (Interp *) interp;
register Var *varPtr;
Var *arrayPtr;
Tcl_Obj *oldValuePtr;
Tcl_Obj *resultPtr = NULL;
char *part1, *bytes;
char *part2 = NULL;
int length, result;
/*
* THIS FAILS IF A NAME OBJECT'S STRING REP HAS A NULL BYTE.
*/
part1 = TclGetStringFromObj(part1Ptr, (int *) NULL);
if (part2Ptr != NULL) {
part2 = TclGetStringFromObj(part2Ptr, (int *) NULL);
}
varPtr = TclLookupVar(interp, part1, part2, flags, "set",
/*createPart1*/ 1, /*createPart2*/ 1, &arrayPtr);
if (varPtr == NULL) {
return NULL;
}
/*
* If the variable is in a hashtable and its hPtr field is NULL, then we
* have an upvar to an array element where the array was deleted,
* leaving the element dangling at the end of the upvar. Generate an
* error (allowing the variable to be reset would screw up our storage
* allocation and is meaningless anyway).
*/
if ((varPtr->flags & VAR_IN_HASHTABLE) && (varPtr->hPtr == NULL)) {
if (flags & TCL_LEAVE_ERR_MSG) {
VarErrMsg(interp, part1, part2, "set", danglingUpvar);
}
return NULL;
}
/*
* It's an error to try to set an array variable itself.
*/
if (TclIsVarArray(varPtr) && !TclIsVarUndefined(varPtr)) {
if (flags & TCL_LEAVE_ERR_MSG) {
VarErrMsg(interp, part1, part2, "set", isArray);
}
return NULL;
}
/*
* At this point, if we were appending, we used to call read traces: we
* treated append as a read-modify-write. However, it seemed unlikely to
* us that a real program would be interested in such reads being done
* during a set operation.
*/
/*
* Set the variable's new value. If appending, append the new value to
* the variable, either as a list element or as a string. Also, if
* appending, then if the variable's old value is unshared we can modify
* it directly, otherwise we must create a new copy to modify: this is
* "copy on write".
*/
oldValuePtr = varPtr->value.objPtr;
if (flags & TCL_APPEND_VALUE) {
if (TclIsVarUndefined(varPtr) && (oldValuePtr != NULL)) {
Tcl_DecrRefCount(oldValuePtr); /* discard old value */
varPtr->value.objPtr = NULL;
oldValuePtr = NULL;
}
if (flags & TCL_LIST_ELEMENT) { /* append list element */
if (oldValuePtr == NULL) {
TclNewObj(oldValuePtr);
varPtr->value.objPtr = oldValuePtr;
Tcl_IncrRefCount(oldValuePtr); /* since var is reference */
} else if (Tcl_IsShared(oldValuePtr)) {
varPtr->value.objPtr = Tcl_DuplicateObj(oldValuePtr);
Tcl_DecrRefCount(oldValuePtr);
oldValuePtr = varPtr->value.objPtr;
Tcl_IncrRefCount(oldValuePtr); /* since var is reference */
}
result = Tcl_ListObjAppendElement(interp, oldValuePtr,
newValuePtr);
if (result != TCL_OK) {
return NULL;
}
} else { /* append string */
/*
* We append newValuePtr's bytes but don't change its ref count.
*/
bytes = Tcl_GetStringFromObj(newValuePtr, &length);
if (oldValuePtr == NULL) {
varPtr->value.objPtr = Tcl_NewStringObj(bytes, length);
Tcl_IncrRefCount(varPtr->value.objPtr);
} else {
if (Tcl_IsShared(oldValuePtr)) { /* append to copy */
varPtr->value.objPtr = Tcl_DuplicateObj(oldValuePtr);
TclDecrRefCount(oldValuePtr);
oldValuePtr = varPtr->value.objPtr;
Tcl_IncrRefCount(oldValuePtr); /* since var is ref */
}
Tcl_AppendToObj(oldValuePtr, bytes, length);
}
}
} else {
if (flags & TCL_LIST_ELEMENT) { /* set var to list element */
int neededBytes, listFlags;
/*
* We set the variable to the result of converting newValuePtr's
* string rep to a list element. We do not change newValuePtr's
* ref count.
*/
if (oldValuePtr != NULL) {
Tcl_DecrRefCount(oldValuePtr); /* discard old value */
}
bytes = Tcl_GetStringFromObj(newValuePtr, &length);
neededBytes = Tcl_ScanElement(bytes, &listFlags);
oldValuePtr = Tcl_NewObj();
oldValuePtr->bytes = (char *)
ckalloc((unsigned) (neededBytes + 1));
oldValuePtr->length = Tcl_ConvertElement(bytes,
oldValuePtr->bytes, listFlags);
varPtr->value.objPtr = oldValuePtr;
Tcl_IncrRefCount(varPtr->value.objPtr);
} else if (newValuePtr != oldValuePtr) {
varPtr->value.objPtr = newValuePtr;
Tcl_IncrRefCount(newValuePtr); /* var is another ref */
if (oldValuePtr != NULL) {
TclDecrRefCount(oldValuePtr); /* discard old value */
}
}
}
TclSetVarScalar(varPtr);
TclClearVarUndefined(varPtr);
if (arrayPtr != NULL) {
TclClearVarUndefined(arrayPtr);
}
/*
* Invoke any write traces for the variable.
*/
if ((varPtr->tracePtr != NULL)
|| ((arrayPtr != NULL) && (arrayPtr->tracePtr != NULL))) {
char *msg = CallTraces(iPtr, arrayPtr, varPtr, part1, part2,
(flags & (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY|TCL_PARSE_PART1)) | TCL_TRACE_WRITES);
if (msg != NULL) {
if (flags & TCL_LEAVE_ERR_MSG) {
VarErrMsg(interp, part1, part2, "set", msg);
}
goto cleanup;
}
}
/*
* Return the variable's value unless the variable was changed in some
* gross way by a trace (e.g. it was unset and then recreated as an
* array).
*/
if (TclIsVarScalar(varPtr) && !TclIsVarUndefined(varPtr)) {
return varPtr->value.objPtr;
}
/*
* A trace changed the value in some gross way. Return an empty string
* object.
*/
resultPtr = iPtr->emptyObjPtr;
/*
* If the variable doesn't exist anymore and no-one's using it, then
* free up the relevant structures and hash table entries.
*/
cleanup:
if (TclIsVarUndefined(varPtr)) {
CleanupVar(varPtr, arrayPtr);
}
return resultPtr;
}
/*
*----------------------------------------------------------------------
*
* TclSetIndexedScalar --
*
* Change the Tcl object value of a local scalar variable in the active
* procedure, given its compile-time allocated index in the procedure's
* array of local variables.
*
* Results:
* Returns a pointer to the Tcl_Obj holding the new value of the
* variable given by localIndex. If the specified variable doesn't
* exist, or there is a clash in array usage, or an error occurs while
* executing variable traces, then NULL is returned and a message will
* be left in the interpreter's result if leaveErrorMsg is 1. Note
* that the returned object may not be the same one referenced by
* newValuePtr; this is because variable traces may modify the
* variable's value.
*
* Side effects:
* The value of the given variable is set. The reference count is
* decremented for any old value of the variable and incremented for
* its new value. If as a result of a variable trace the new value for
* the variable is not the same one referenced by newValuePtr, then
* newValuePtr's ref count is left unchanged. The ref count for the
* returned object is _not_ incremented to reflect the returned
* reference; if you want to keep a reference to the object you must
* increment its ref count yourself. This procedure does not create
* new variables, but only sets those recognized at compile time.
*
*----------------------------------------------------------------------
*/
Tcl_Obj *
TclSetIndexedScalar(interp, localIndex, newValuePtr, leaveErrorMsg)
Tcl_Interp *interp; /* Command interpreter in which variable is
* to be found. */
int localIndex; /* Index of variable in procedure's array
* of local variables. */
Tcl_Obj *newValuePtr; /* New value for variable. */
int leaveErrorMsg; /* 1 if to leave an error message in
* the interpreter's result on an error.
* Otherwise no error message is left. */
{
Interp *iPtr = (Interp *) interp;
CallFrame *varFramePtr = iPtr->varFramePtr;
/* Points to the procedure call frame whose
* variables are currently in use. Same as
* the current procedure's frame, if any,
* unless an "uplevel" is executing. */
Var *compiledLocals = varFramePtr->compiledLocals;
register Var *varPtr; /* Points to the variable's in-frame Var
* structure. */
char *varName; /* Name of the local variable. */
Tcl_Obj *oldValuePtr;
Tcl_Obj *resultPtr = NULL;
#ifdef TCL_COMPILE_DEBUG
Proc *procPtr = varFramePtr->procPtr;
int localCt = procPtr->numCompiledLocals;
if (compiledLocals == NULL) {
fprintf(stderr, "\nTclSetIndexedScalar: can't set local %i in frame 0x%x, no compiled locals\n",
localIndex, (unsigned int) varFramePtr);
panic("TclSetIndexedScalar: no compiled locals in frame 0x%x",
(unsigned int) varFramePtr);
}
if ((localIndex < 0) || (localIndex >= localCt)) {
fprintf(stderr, "\nTclSetIndexedScalar: can't set local %i in frame 0x%x with %i locals\n",
localIndex, (unsigned int) varFramePtr, localCt);
panic("TclSetIndexedScalar: bad local index %i in frame 0x%x",
localIndex, (unsigned int) varFramePtr);
}
#endif /* TCL_COMPILE_DEBUG */
varPtr = &(compiledLocals[localIndex]);
varName = varPtr->name;
/*
* If varPtr is a link variable, we have a reference to some variable
* that was created through an "upvar" or "global" command, or we have a
* reference to a variable in an enclosing namespace. Traverse through
* any links until we find the referenced variable.
*/
while (TclIsVarLink(varPtr)) {
varPtr = varPtr->value.linkPtr;
}
/*
* If the variable is in a hashtable and its hPtr field is NULL, then we
* have an upvar to an array element where the array was deleted,
* leaving the element dangling at the end of the upvar. Generate an
* error (allowing the variable to be reset would screw up our storage
* allocation and is meaningless anyway).
*/
if ((varPtr->flags & VAR_IN_HASHTABLE) && (varPtr->hPtr == NULL)) {
if (leaveErrorMsg) {
VarErrMsg(interp, varName, NULL, "set", danglingUpvar);
}
return NULL;
}
/*
* It's an error to try to set an array variable itself.
*/
if (TclIsVarArray(varPtr) && !TclIsVarUndefined(varPtr)) {
if (leaveErrorMsg) {
VarErrMsg(interp, varName, NULL, "set", isArray);
}
return NULL;
}
/*
* Set the variable's new value and discard its old value. We don't
* append with this "set" procedure so the old value isn't needed.
*/
oldValuePtr = varPtr->value.objPtr;
if (newValuePtr != oldValuePtr) { /* set new value */
varPtr->value.objPtr = newValuePtr;
Tcl_IncrRefCount(newValuePtr); /* var is another ref to obj */
if (oldValuePtr != NULL) {
TclDecrRefCount(oldValuePtr); /* discard old value */
}
}
TclSetVarScalar(varPtr);
TclClearVarUndefined(varPtr);
/*
* Invoke any write traces for the variable.
*/
if (varPtr->tracePtr != NULL) {
char *msg = CallTraces(iPtr, /*arrayPtr*/ NULL, varPtr,
varName, (char *) NULL, TCL_TRACE_WRITES);
if (msg != NULL) {
if (leaveErrorMsg) {
VarErrMsg(interp, varName, NULL, "set", msg);
}
goto cleanup;
}
}
/*
* Return the variable's value unless the variable was changed in some
* gross way by a trace (e.g. it was unset and then recreated as an
* array). If it was changed is a gross way, just return an empty string
* object.
*/
if (TclIsVarScalar(varPtr) && !TclIsVarUndefined(varPtr)) {
return varPtr->value.objPtr;
}
resultPtr = Tcl_NewObj();
/*
* If the variable doesn't exist anymore and no-one's using it, then
* free up the relevant structures and hash table entries.
*/
cleanup:
if (TclIsVarUndefined(varPtr)) {
CleanupVar(varPtr, NULL);
}
return resultPtr;
}
/*
*----------------------------------------------------------------------
*
* TclSetElementOfIndexedArray --
*
* Change the Tcl object value of an element in a local array
* variable. The element is named by the object elemPtr while the array
* is specified by its index in the active procedure's array of
* compiler allocated local variables.
*
* Results:
* Returns a pointer to the Tcl_Obj holding the new value of the
* element. If the specified array or element doesn't exist, or there
* is a clash in array usage, or an error occurs while executing
* variable traces, then NULL is returned and a message will be left in
* the interpreter's result if leaveErrorMsg is 1. Note that the
* returned object may not be the same one referenced by newValuePtr;
* this is because variable traces may modify the variable's value.
*
* Side effects:
* The value of the given array element is set. The reference count is
* decremented for any old value of the element and incremented for its
* new value. If as a result of a variable trace the new value for the
* element is not the same one referenced by newValuePtr, then
* newValuePtr's ref count is left unchanged. The ref count for the
* returned object is _not_ incremented to reflect the returned
* reference; if you want to keep a reference to the object you must
* increment its ref count yourself. This procedure will not create new
* array variables, but only sets elements of those arrays recognized
* at compile time. However, if the entry doesn't exist then a new
* variable is created.
*
*----------------------------------------------------------------------
*/
Tcl_Obj *
TclSetElementOfIndexedArray(interp, localIndex, elemPtr, newValuePtr,
leaveErrorMsg)
Tcl_Interp *interp; /* Command interpreter in which the array is
* to be found. */
int localIndex; /* Index of array variable in procedure's
* array of local variables. */
Tcl_Obj *elemPtr; /* Points to an object holding the name of
* an element to set in the array. */
Tcl_Obj *newValuePtr; /* New value for variable. */
int leaveErrorMsg; /* 1 if to leave an error message in
* the interpreter's result on an error.
* Otherwise no error message is left. */
{
Interp *iPtr = (Interp *) interp;
CallFrame *varFramePtr = iPtr->varFramePtr;
/* Points to the procedure call frame whose
* variables are currently in use. Same as
* the current procedure's frame, if any,
* unless an "uplevel" is executing. */
Var *compiledLocals = varFramePtr->compiledLocals;
Var *arrayPtr; /* Points to the array's in-frame Var
* structure. */
char *arrayName; /* Name of the local array. */
char *elem;
Tcl_HashEntry *hPtr;
Var *varPtr = NULL; /* Points to the element's Var structure
* that we return. */
Tcl_Obj *resultPtr = NULL;
Tcl_Obj *oldValuePtr;
int new;
#ifdef TCL_COMPILE_DEBUG
Proc *procPtr = varFramePtr->procPtr;
int localCt = procPtr->numCompiledLocals;
if (compiledLocals == NULL) {
fprintf(stderr, "\nTclSetElementOfIndexedArray: can't set element of local %i in frame 0x%x, no compiled locals\n",
localIndex, (unsigned int) varFramePtr);
panic("TclSetIndexedScalar: no compiled locals in frame 0x%x",
(unsigned int) varFramePtr);
}
if ((localIndex < 0) || (localIndex >= localCt)) {
fprintf(stderr, "\nTclSetIndexedScalar: can't set elememt of local %i in frame 0x%x with %i locals\n",
localIndex, (unsigned int) varFramePtr, localCt);
panic("TclSetElementOfIndexedArray: bad local index %i in frame 0x%x",
localIndex, (unsigned int) varFramePtr);
}
#endif /* TCL_COMPILE_DEBUG */
/*
* THIS FAILS IF THE ELEMENT NAME OBJECT'S STRING REP HAS A NULL BYTE.
*/
elem = Tcl_GetStringFromObj(elemPtr, (int *) NULL);
arrayPtr = &(compiledLocals[localIndex]);
arrayName = arrayPtr->name;
/*
* If arrayPtr is a link variable, we have a reference to some variable
* that was created through an "upvar" or "global" command, or we have a
* reference to a variable in an enclosing namespace. Traverse through
* any links until we find the referenced variable.
*/
while (TclIsVarLink(arrayPtr)) {
arrayPtr = arrayPtr->value.linkPtr;
}
/*
* Make sure we're dealing with an array.
*/
if (TclIsVarUndefined(arrayPtr) && !TclIsVarArrayElement(arrayPtr)) {
TclSetVarArray(arrayPtr);
arrayPtr->value.tablePtr =
(Tcl_HashTable *) ckalloc(sizeof(Tcl_HashTable));
Tcl_InitHashTable(arrayPtr->value.tablePtr, TCL_STRING_KEYS);
TclClearVarUndefined(arrayPtr);
} else if (!TclIsVarArray(arrayPtr)) {
if (leaveErrorMsg) {
VarErrMsg(interp, arrayName, elem, "set", needArray);
}
goto errorReturn;
}
/*
* Look up the element.
*/
hPtr = Tcl_CreateHashEntry(arrayPtr->value.tablePtr, elem, &new);
if (new) {
if (arrayPtr->searchPtr != NULL) {
DeleteSearches(arrayPtr);
}
varPtr = NewVar();
Tcl_SetHashValue(hPtr, varPtr);
varPtr->hPtr = hPtr;
varPtr->nsPtr = varFramePtr->nsPtr;
TclSetVarArrayElement(varPtr);
}
varPtr = (Var *) Tcl_GetHashValue(hPtr);
/*
* It's an error to try to set an array variable itself.
*/
if (TclIsVarArray(varPtr)) {
if (leaveErrorMsg) {
VarErrMsg(interp, arrayName, elem, "set", isArray);
}
goto errorReturn;
}
/*
* Set the variable's new value and discard the old one. We don't
* append with this "set" procedure so the old value isn't needed.
*/
oldValuePtr = varPtr->value.objPtr;
if (newValuePtr != oldValuePtr) { /* set new value */
varPtr->value.objPtr = newValuePtr;
Tcl_IncrRefCount(newValuePtr); /* var is another ref to obj */
if (oldValuePtr != NULL) {
TclDecrRefCount(oldValuePtr); /* discard old value */
}
}
TclSetVarScalar(varPtr);
TclClearVarUndefined(varPtr);
/*
* Invoke any write traces for the element variable.
*/
if ((varPtr->tracePtr != NULL)
|| ((arrayPtr != NULL) && (arrayPtr->tracePtr != NULL))) {
char *msg = CallTraces(iPtr, arrayPtr, varPtr, arrayName, elem,
TCL_TRACE_WRITES);
if (msg != NULL) {
if (leaveErrorMsg) {
VarErrMsg(interp, arrayName, elem, "set", msg);
}
goto errorReturn;
}
}
/*
* Return the element's value unless it was changed in some gross way by
* a trace (e.g. it was unset and then recreated as an array). If it was
* changed is a gross way, just return an empty string object.
*/
if (TclIsVarScalar(varPtr) && !TclIsVarUndefined(varPtr)) {
return varPtr->value.objPtr;
}
resultPtr = Tcl_NewObj();
/*
* An error. If the variable doesn't exist anymore and no-one's using
* it, then free up the relevant structures and hash table entries.
*/
errorReturn:
if (varPtr != NULL) {
if (TclIsVarUndefined(varPtr)) {
CleanupVar(varPtr, NULL); /* note: array isn't in hashtable */
}
}
return resultPtr;
}
/*
*----------------------------------------------------------------------
*
* TclIncrVar2 --
*
* Given a two-part variable name, which may refer either to a scalar
* variable or an element of an array, increment the Tcl object value
* of the variable by a specified amount.
*
* Results:
* Returns a pointer to the Tcl_Obj holding the new value of the
* variable. If the specified variable doesn't exist, or there is a
* clash in array usage, or an error occurs while executing variable
* traces, then NULL is returned and a message will be left in
* the interpreter's result.
*
* Side effects:
* The value of the given variable is incremented by the specified
* amount. If either the array or the entry didn't exist then a new
* variable is created. The ref count for the returned object is _not_
* incremented to reflect the returned reference; if you want to keep a
* reference to the object you must increment its ref count yourself.
*
*----------------------------------------------------------------------
*/
Tcl_Obj *
TclIncrVar2(interp, part1Ptr, part2Ptr, incrAmount, part1NotParsed)
Tcl_Interp *interp; /* Command interpreter in which variable is
* to be found. */
Tcl_Obj *part1Ptr; /* Points to an object holding the name of
* an array (if part2 is non-NULL) or the
* name of a variable. */
Tcl_Obj *part2Ptr; /* If non-null, points to an object holding
* the name of an element in the array
* part1Ptr. */
long incrAmount; /* Amount to be added to variable. */
int part1NotParsed; /* 1 if part1 hasn't yet been parsed into
* an array name and index (if any). */
{
register Tcl_Obj *varValuePtr;
Tcl_Obj *resultPtr;
int createdNewObj; /* Set 1 if var's value object is shared
* so we must increment a copy (i.e. copy
* on write). */
long i;
int flags, result;
flags = TCL_LEAVE_ERR_MSG;
if (part1NotParsed) {
flags |= TCL_PARSE_PART1;
}
varValuePtr = Tcl_ObjGetVar2(interp, part1Ptr, part2Ptr, flags);
if (varValuePtr == NULL) {
Tcl_AddObjErrorInfo(interp,
"\n (reading value of variable to increment)", -1);
return NULL;
}
/*
* Increment the variable's value. If the object is unshared we can
* modify it directly, otherwise we must create a new copy to modify:
* this is "copy on write". Then free the variable's old string
* representation, if any, since it will no longer be valid.
*/
createdNewObj = 0;
if (Tcl_IsShared(varValuePtr)) {
varValuePtr = Tcl_DuplicateObj(varValuePtr);
createdNewObj = 1;
}
result = Tcl_GetLongFromObj(interp, varValuePtr, &i);
if (result != TCL_OK) {
if (createdNewObj) {
Tcl_DecrRefCount(varValuePtr); /* free unneeded copy */
}
return NULL;
}
Tcl_SetLongObj(varValuePtr, (i + incrAmount));
/*
* Store the variable's new value and run any write traces.
*/
resultPtr = Tcl_ObjSetVar2(interp, part1Ptr, part2Ptr, varValuePtr,
flags);
if (resultPtr == NULL) {
return NULL;
}
return resultPtr;
}
/*
*----------------------------------------------------------------------
*
* TclIncrIndexedScalar --
*
* Increments the Tcl object value of a local scalar variable in the
* active procedure, given its compile-time allocated index in the
* procedure's array of local variables.
*
* Results:
* Returns a pointer to the Tcl_Obj holding the new value of the
* variable given by localIndex. If the specified variable doesn't
* exist, or there is a clash in array usage, or an error occurs while
* executing variable traces, then NULL is returned and a message will
* be left in the interpreter's result.
*
* Side effects:
* The value of the given variable is incremented by the specified
* amount. The ref count for the returned object is _not_ incremented
* to reflect the returned reference; if you want to keep a reference
* to the object you must increment its ref count yourself.
*
*----------------------------------------------------------------------
*/
Tcl_Obj *
TclIncrIndexedScalar(interp, localIndex, incrAmount)
Tcl_Interp *interp; /* Command interpreter in which variable is
* to be found. */
int localIndex; /* Index of variable in procedure's array
* of local variables. */
long incrAmount; /* Amount to be added to variable. */
{
register Tcl_Obj *varValuePtr;
Tcl_Obj *resultPtr;
int createdNewObj; /* Set 1 if var's value object is shared
* so we must increment a copy (i.e. copy
* on write). */
long i;
int result;
varValuePtr = TclGetIndexedScalar(interp, localIndex,
/*leaveErrorMsg*/ 1);
if (varValuePtr == NULL) {
Tcl_AddObjErrorInfo(interp,
"\n (reading value of variable to increment)", -1);
return NULL;
}
/*
* Reach into the object's representation to extract and increment the
* variable's value. If the object is unshared we can modify it
* directly, otherwise we must create a new copy to modify: this is
* "copy on write". Then free the variable's old string representation,
* if any, since it will no longer be valid.
*/
createdNewObj = 0;
if (Tcl_IsShared(varValuePtr)) {
createdNewObj = 1;
varValuePtr = Tcl_DuplicateObj(varValuePtr);
}
result = Tcl_GetLongFromObj(interp, varValuePtr, &i);
if (result != TCL_OK) {
if (createdNewObj) {
Tcl_DecrRefCount(varValuePtr); /* free unneeded copy */
}
return NULL;
}
Tcl_SetLongObj(varValuePtr, (i + incrAmount));
/*
* Store the variable's new value and run any write traces.
*/
resultPtr = TclSetIndexedScalar(interp, localIndex, varValuePtr,
/*leaveErrorMsg*/ 1);
if (resultPtr == NULL) {
return NULL;
}
return resultPtr;
}
/*
*----------------------------------------------------------------------
*
* TclIncrElementOfIndexedArray --
*
* Increments the Tcl object value of an element in a local array
* variable. The element is named by the object elemPtr while the array
* is specified by its index in the active procedure's array of
* compiler allocated local variables.
*
* Results:
* Returns a pointer to the Tcl_Obj holding the new value of the
* element. If the specified array or element doesn't exist, or there
* is a clash in array usage, or an error occurs while executing
* variable traces, then NULL is returned and a message will be left in
* the interpreter's result.
*
* Side effects:
* The value of the given array element is incremented by the specified
* amount. The ref count for the returned object is _not_ incremented
* to reflect the returned reference; if you want to keep a reference
* to the object you must increment its ref count yourself. If the
* entry doesn't exist then a new variable is created.
*
*----------------------------------------------------------------------
*/
Tcl_Obj *
TclIncrElementOfIndexedArray(interp, localIndex, elemPtr, incrAmount)
Tcl_Interp *interp; /* Command interpreter in which the array is
* to be found. */
int localIndex; /* Index of array variable in procedure's
* array of local variables. */
Tcl_Obj *elemPtr; /* Points to an object holding the name of
* an element to increment in the array. */
long incrAmount; /* Amount to be added to variable. */
{
register Tcl_Obj *varValuePtr;
Tcl_Obj *resultPtr;
int createdNewObj; /* Set 1 if var's value object is shared
* so we must increment a copy (i.e. copy
* on write). */
long i;
int result;
varValuePtr = TclGetElementOfIndexedArray(interp, localIndex, elemPtr,
/*leaveErrorMsg*/ 1);
if (varValuePtr == NULL) {
Tcl_AddObjErrorInfo(interp,
"\n (reading value of variable to increment)", -1);
return NULL;
}
/*
* Reach into the object's representation to extract and increment the
* variable's value. If the object is unshared we can modify it
* directly, otherwise we must create a new copy to modify: this is
* "copy on write". Then free the variable's old string representation,
* if any, since it will no longer be valid.
*/
createdNewObj = 0;
if (Tcl_IsShared(varValuePtr)) {
createdNewObj = 1;
varValuePtr = Tcl_DuplicateObj(varValuePtr);
}
result = Tcl_GetLongFromObj(interp, varValuePtr, &i);
if (result != TCL_OK) {
if (createdNewObj) {
Tcl_DecrRefCount(varValuePtr); /* free unneeded copy */
}
return NULL;
}
Tcl_SetLongObj(varValuePtr, (i + incrAmount));
/*
* Store the variable's new value and run any write traces.
*/
resultPtr = TclSetElementOfIndexedArray(interp, localIndex, elemPtr,
varValuePtr,
/*leaveErrorMsg*/ 1);
if (resultPtr == NULL) {
return NULL;
}
return resultPtr;
}
/*
*----------------------------------------------------------------------
*
* Tcl_UnsetVar --
*
* Delete a variable, so that it may not be accessed anymore.
*
* Results:
* Returns TCL_OK if the variable was successfully deleted, TCL_ERROR
* 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, TCL_NAMESPACE_ONLY or
* TCL_LEAVE_ERR_MSG. */
{
return Tcl_UnsetVar2(interp, varName, (char *) NULL,
(flags | TCL_PARSE_PART1));
}
/*
*----------------------------------------------------------------------
*
* Tcl_UnsetVar2 --
*
* Delete a variable, given a 2-part name.
*
* Results:
* Returns TCL_OK if the variable was successfully deleted, TCL_ERROR
* 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 part1 and part2 indicate a local or global variable in interp,
* it is deleted. If part1 is an array name and part2 is NULL, then
* the whole array is deleted.
*
*----------------------------------------------------------------------
*/
int
Tcl_UnsetVar2(interp, part1, part2, flags)
Tcl_Interp *interp; /* Command interpreter in which varName is
* to be looked up. */
char *part1; /* Name of variable or array. */
char *part2; /* Name of element within array or NULL. */
int flags; /* OR-ed combination of any of
* TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY,
* TCL_LEAVE_ERR_MSG, or
* TCL_PARSE_PART1. */
{
Var dummyVar;
Var *varPtr, *dummyVarPtr;
Interp *iPtr = (Interp *) interp;
Var *arrayPtr;
ActiveVarTrace *activePtr;
Tcl_Obj *objPtr;
int result;
varPtr = TclLookupVar(interp, part1, part2, flags, "unset",
/*createPart1*/ 0, /*createPart2*/ 0, &arrayPtr);
if (varPtr == NULL) {
return TCL_ERROR;
}
result = (TclIsVarUndefined(varPtr)? TCL_ERROR : TCL_OK);
if ((arrayPtr != NULL) && (arrayPtr->searchPtr != NULL)) {
DeleteSearches(arrayPtr);
}
/*
* 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, do things
* in three steps:
* 1. Copy the contents of the variable to a dummy variable
* structure, and mark the original Var structure as undefined.
* 2. Invoke traces and clean up the variable, using the dummy copy.
* 3. If at the end of this the original variable is still
* undefined and has no outstanding references, then delete
* it (but it could have gotten recreated by a trace).
*/
dummyVar = *varPtr;
TclSetVarUndefined(varPtr);
TclSetVarScalar(varPtr);
varPtr->value.objPtr = NULL; /* dummyVar points to any value object */
varPtr->tracePtr = NULL;
varPtr->searchPtr = NULL;
/*
* Call trace procedures for the variable being deleted. Then delete
* its traces. Be sure to abort any other traces for the variable
* that are still pending. Special tricks:
* 1. We need to increment varPtr's refCount around this: CallTraces
* will use dummyVar so it won't increment varPtr's refCount itself.
* 2. Turn off the VAR_TRACE_ACTIVE flag in dummyVar: we want to
* call unset traces even if other traces are pending.
*/
if ((dummyVar.tracePtr != NULL)
|| ((arrayPtr != NULL) && (arrayPtr->tracePtr != NULL))) {
varPtr->refCount++;
dummyVar.flags &= ~VAR_TRACE_ACTIVE;
(void) CallTraces(iPtr, arrayPtr, &dummyVar, part1, part2,
(flags & (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY|TCL_PARSE_PART1)) | TCL_TRACE_UNSETS);
while (dummyVar.tracePtr != NULL) {
VarTrace *tracePtr = dummyVar.tracePtr;
dummyVar.tracePtr = tracePtr->nextPtr;
ckfree((char *) tracePtr);
}
for (activePtr = iPtr->activeTracePtr; activePtr != NULL;
activePtr = activePtr->nextPtr) {
if (activePtr->varPtr == varPtr) {
activePtr->nextTracePtr = NULL;
}
}
varPtr->refCount--;
}
/*
* 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 it is a scalar, "discard" its object
* (decrement the ref count of its object, if any).
*/
dummyVarPtr = &dummyVar;
if (TclIsVarArray(dummyVarPtr) && !TclIsVarUndefined(dummyVarPtr)) {
DeleteArray(iPtr, part1, dummyVarPtr,
(flags & (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY)) | TCL_TRACE_UNSETS);
}
if (TclIsVarScalar(dummyVarPtr)
&& (dummyVarPtr->value.objPtr != NULL)) {
objPtr = dummyVarPtr->value.objPtr;
TclDecrRefCount(objPtr);
dummyVarPtr->value.objPtr = NULL;
}
/*
* If the variable was a namespace variable, decrement its reference
* count. We are in the process of destroying its namespace so that
* namespace will no longer "refer" to the variable.
*/
if (varPtr->flags & VAR_NAMESPACE_VAR) {
varPtr->flags &= ~VAR_NAMESPACE_VAR;
varPtr->refCount--;
}
/*
* It's an error to unset an undefined variable.
*/
if (result != TCL_OK) {
if (flags & TCL_LEAVE_ERR_MSG) {
VarErrMsg(interp, part1, part2, "unset",
((arrayPtr == NULL) ? noSuchVar : noSuchElement));
}
}
/*
* Finally, if the variable is truly not in use then free up its Var
* structure and remove it from its hash table, if any. The ref count of
* its value object, if any, was decremented above.
*/
CleanupVar(varPtr, arrayPtr);
return result;
}
/*
*----------------------------------------------------------------------
*
* 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, TCL_GLOBAL_ONLY, and
* TCL_NAMESPACE_ONLY. */
Tcl_VarTraceProc *proc; /* Procedure to call when specified ops are
* invoked upon varName. */
ClientData clientData; /* Arbitrary argument to pass to proc. */
{
return Tcl_TraceVar2(interp, varName, (char *) NULL,
(flags | TCL_PARSE_PART1), 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 part1 and part2, 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, part1, part2, flags, proc, clientData)
Tcl_Interp *interp; /* Interpreter in which variable is
* to be traced. */
char *part1; /* Name of scalar variable or array. */
char *part2; /* 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, TCL_GLOBAL_ONLY,
* TCL_NAMESPACE_ONLY and
* TCL_PARSE_PART1. */
Tcl_VarTraceProc *proc; /* Procedure to call when specified ops are
* invoked upon varName. */
ClientData clientData; /* Arbitrary argument to pass to proc. */
{
Var *varPtr, *arrayPtr;
register VarTrace *tracePtr;
varPtr = TclLookupVar(interp, part1, part2, (flags | TCL_LEAVE_ERR_MSG),
"trace", /*createPart1*/ 1, /*createPart2*/ 1, &arrayPtr);
if (varPtr == NULL) {
return TCL_ERROR;
}
/*
* 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 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, TCL_GLOBAL_ONLY
* and TCL_NAMESPACE_ONLY. */
Tcl_VarTraceProc *proc; /* Procedure assocated with trace. */
ClientData clientData; /* Arbitrary argument to pass to proc. */
{
Tcl_UntraceVar2(interp, varName, (char *) NULL,
(flags | TCL_PARSE_PART1), 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 part1
* and part2 with the given flags, proc, and clientData, then
* that trace is removed.
*
*----------------------------------------------------------------------
*/
void
Tcl_UntraceVar2(interp, part1, part2, flags, proc, clientData)
Tcl_Interp *interp; /* Interpreter containing variable. */
char *part1; /* Name of variable or array. */
char *part2; /* 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, TCL_GLOBAL_ONLY,
* TCL_NAMESPACE_ONLY and
* TCL_PARSE_PART1. */
Tcl_VarTraceProc *proc; /* Procedure assocated with trace. */
ClientData clientData; /* Arbitrary argument to pass to proc. */
{
register VarTrace *tracePtr;
VarTrace *prevPtr;
Var *varPtr, *arrayPtr;
Interp *iPtr = (Interp *) interp;
ActiveVarTrace *activePtr;
varPtr = TclLookupVar(interp, part1, part2,
flags & (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY|TCL_PARSE_PART1),
/*msg*/ (char *) NULL,
/*createPart1*/ 0, /*createPart2*/ 0, &arrayPtr);
if (varPtr == NULL) {
return;
}
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);
/*
* If this is the last trace on the variable, and the variable is
* unset and unused, then free up the variable.
*/
if (TclIsVarUndefined(varPtr)) {
CleanupVar(varPtr, (Var *) NULL);
}
}
/*
*----------------------------------------------------------------------
*
* 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, TCL_GLOBAL_ONLY, or
* TCL_NAMESPACE_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. */
{
return Tcl_VarTraceInfo2(interp, varName, (char *) NULL,
(flags | TCL_PARSE_PART1), 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, part1, part2, flags, proc, prevClientData)
Tcl_Interp *interp; /* Interpreter containing variable. */
char *part1; /* Name of variable or array. */
char *part2; /* Name of element within array; NULL means
* trace applies to scalar variable or array
* as-a-whole. */
int flags; /* OR-ed combination of TCL_GLOBAL_ONLY,
* TCL_NAMESPACE_ONLY, and
* TCL_PARSE_PART1. */
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, *arrayPtr;
varPtr = TclLookupVar(interp, part1, part2,
flags & (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY|TCL_PARSE_PART1),
/*msg*/ (char *) NULL,
/*createPart1*/ 0, /*createPart2*/ 0, &arrayPtr);
if (varPtr == NULL) {
return NULL;
}
/*
* 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_UnsetObjCmd --
*
* This object-based procedure is invoked to process the "unset" Tcl
* command. See the user documentation for details on what it does.
*
* Results:
* A standard Tcl object result value.
*
* Side effects:
* See the user documentation.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
int
Tcl_UnsetObjCmd(dummy, interp, objc, objv)
ClientData dummy; /* Not used. */
Tcl_Interp *interp; /* Current interpreter. */
int objc; /* Number of arguments. */
Tcl_Obj *CONST objv[]; /* Argument objects. */
{
register int i;
register char *name;
if (objc < 2) {
Tcl_WrongNumArgs(interp, 1, objv, "varName ?varName ...?");
return TCL_ERROR;
}
for (i = 1; i < objc; i++) {
/*
* THIS FAILS IF A NAME OBJECT'S STRING REP HAS A NULL BYTE.
*/
name = Tcl_GetStringFromObj(objv[i], (int *) NULL);
if (Tcl_UnsetVar2(interp, name, (char *) NULL,
(TCL_LEAVE_ERR_MSG | TCL_PARSE_PART1)) != TCL_OK) {
return TCL_ERROR;
}
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_AppendObjCmd --
*
* This object-based procedure is invoked to process the "append"
* Tcl command. See the user documentation for details on what it does.
*
* Results:
* A standard Tcl object result value.
*
* Side effects:
* A variable's value may be changed.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
int
Tcl_AppendObjCmd(dummy, interp, objc, objv)
ClientData dummy; /* Not used. */
Tcl_Interp *interp; /* Current interpreter. */
int objc; /* Number of arguments. */
Tcl_Obj *CONST objv[]; /* Argument objects. */
{
register Tcl_Obj *varValuePtr = NULL;
/* Initialized to avoid compiler
* warning. */
int i;
if (objc < 2) {
Tcl_WrongNumArgs(interp, 1, objv, "varName ?value value ...?");
return TCL_ERROR;
}
if (objc == 2) {
varValuePtr = Tcl_ObjGetVar2(interp, objv[1], (Tcl_Obj *) NULL,
(TCL_LEAVE_ERR_MSG | TCL_PARSE_PART1));
if (varValuePtr == NULL) {
return TCL_ERROR;
}
} else {
for (i = 2; i < objc; i++) {
varValuePtr = Tcl_ObjSetVar2(interp, objv[1], (Tcl_Obj *) NULL,
objv[i],
(TCL_APPEND_VALUE | TCL_LEAVE_ERR_MSG | TCL_PARSE_PART1));
if (varValuePtr == NULL) {
return TCL_ERROR;
}
}
}
Tcl_SetObjResult(interp, varValuePtr);
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_LappendObjCmd --
*
* This object-based procedure is invoked to process the "lappend"
* Tcl command. See the user documentation for details on what it does.
*
* Results:
* A standard Tcl object result value.
*
* Side effects:
* A variable's value may be changed.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
int
Tcl_LappendObjCmd(dummy, interp, objc, objv)
ClientData dummy; /* Not used. */
Tcl_Interp *interp; /* Current interpreter. */
int objc; /* Number of arguments. */
Tcl_Obj *CONST objv[]; /* Argument objects. */
{
Tcl_Obj *varValuePtr, *newValuePtr;
register List *listRepPtr;
register Tcl_Obj **elemPtrs;
int numElems, numRequired, createdNewObj, createVar, i, j;
if (objc < 2) {
Tcl_WrongNumArgs(interp, 1, objv, "varName ?value value ...?");
return TCL_ERROR;
}
if (objc == 2) {
newValuePtr = Tcl_ObjGetVar2(interp, objv[1], (Tcl_Obj *) NULL,
(TCL_LEAVE_ERR_MSG | TCL_PARSE_PART1));
if (newValuePtr == NULL) {
/*
* The variable doesn't exist yet. Just create it with an empty
* initial value.
*/
Tcl_Obj *nullObjPtr = Tcl_NewObj();
newValuePtr = Tcl_ObjSetVar2(interp, objv[1], NULL,
nullObjPtr, (TCL_LEAVE_ERR_MSG | TCL_PARSE_PART1));
if (newValuePtr == NULL) {
Tcl_DecrRefCount(nullObjPtr); /* free unneeded object */
return TCL_ERROR;
}
}
} else {
/*
* We have arguments to append. We used to call Tcl_ObjSetVar2 to
* append each argument one at a time to ensure that traces were run
* for each append step. We now append the arguments all at once
* because it's faster. Note that a read trace and a write trace for
* the variable will now each only be called once. Also, if the
* variable's old value is unshared we modify it directly, otherwise
* we create a new copy to modify: this is "copy on write".
*/
createdNewObj = 0;
createVar = 1;
varValuePtr = Tcl_ObjGetVar2(interp, objv[1], (Tcl_Obj *) NULL,
TCL_PARSE_PART1);
if (varValuePtr == NULL) {
/*
* We couldn't read the old value: either the var doesn't yet
* exist or it's an array element. If it's new, we will try to
* create it with Tcl_ObjSetVar2 below.
*/
char *name, *p;
int nameBytes, i;
name = TclGetStringFromObj(objv[1], &nameBytes);
for (i = 0, p = name; i < nameBytes; i++, p++) {
if (*p == '(') {
p = (name + nameBytes-1);
if (*p == ')') { /* last char is ')' => array ref */
createVar = 0;
}
break;
}
}
varValuePtr = Tcl_NewObj();
createdNewObj = 1;
} else if (Tcl_IsShared(varValuePtr)) {
varValuePtr = Tcl_DuplicateObj(varValuePtr);
createdNewObj = 1;
}
/*
* Convert the variable's old value to a list object if necessary.
*/
if (varValuePtr->typePtr != &tclListType) {
int result = tclListType.setFromAnyProc(interp, varValuePtr);
if (result != TCL_OK) {
if (createdNewObj) {
Tcl_DecrRefCount(varValuePtr); /* free unneeded obj. */
}
return result;
}
}
listRepPtr = (List *) varValuePtr->internalRep.otherValuePtr;
elemPtrs = listRepPtr->elements;
numElems = listRepPtr->elemCount;
/*
* If there is no room in the current array of element pointers,
* allocate a new, larger array and copy the pointers to it.
*/
numRequired = numElems + (objc-2);
if (numRequired > listRepPtr->maxElemCount) {
int newMax = (2 * numRequired);
Tcl_Obj **newElemPtrs = (Tcl_Obj **)
ckalloc((unsigned) (newMax * sizeof(Tcl_Obj *)));
memcpy((VOID *) newElemPtrs, (VOID *) elemPtrs,
(size_t) (numElems * sizeof(Tcl_Obj *)));
listRepPtr->maxElemCount = newMax;
listRepPtr->elements = newElemPtrs;
ckfree((char *) elemPtrs);
elemPtrs = newElemPtrs;
}
/*
* Insert the new elements at the end of the list.
*/
for (i = 2, j = numElems; i < objc; i++, j++) {
elemPtrs[j] = objv[i];
Tcl_IncrRefCount(objv[i]);
}
listRepPtr->elemCount = numRequired;
/*
* Invalidate and free any old string representation since it no
* longer reflects the list's internal representation.
*/
Tcl_InvalidateStringRep(varValuePtr);
/*
* Now store the list object back into the variable. If there is an
* error setting the new value, decrement its ref count if it
* was new and we didn't create the variable.
*/
newValuePtr = Tcl_ObjSetVar2(interp, objv[1], (Tcl_Obj *) NULL,
varValuePtr, (TCL_LEAVE_ERR_MSG | TCL_PARSE_PART1));
if (newValuePtr == NULL) {
if (createdNewObj && !createVar) {
Tcl_DecrRefCount(varValuePtr); /* free unneeded obj */
}
return TCL_ERROR;
}
}
/*
* Set the interpreter's object result to refer to the variable's value
* object.
*/
Tcl_SetObjResult(interp, newValuePtr);
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ArrayObjCmd --
*
* This object-based procedure is invoked to process the "array" Tcl
* command. See the user documentation for details on what it does.
*
* Results:
* A standard Tcl result object.
*
* Side effects:
* See the user documentation.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
int
Tcl_ArrayObjCmd(dummy, interp, objc, objv)
ClientData dummy; /* Not used. */
Tcl_Interp *interp; /* Current interpreter. */
int objc; /* Number of arguments. */
Tcl_Obj *CONST objv[]; /* Argument objects. */
{
static char *arrayOptions[] = {"anymore", "donesearch", "exists",
"get", "names", "nextelement", "set", "size", "startsearch",
(char *) NULL};
Var *varPtr, *arrayPtr;
Tcl_HashEntry *hPtr;
Tcl_Obj *resultPtr = Tcl_GetObjResult(interp);
int notArray;
char *varName;
int index, result;
if (objc < 3) {
Tcl_WrongNumArgs(interp, 1, objv, "option arrayName ?arg ...?");
return TCL_ERROR;
}
if (Tcl_GetIndexFromObj(interp, objv[1], arrayOptions, "option", 0, &index)
!= TCL_OK) {
return TCL_ERROR;
}
/*
* Locate the array variable (and it better be an array).
* THIS FAILS IF A NAME OBJECT'S STRING REP HAS A NULL BYTE.
*/
varName = TclGetStringFromObj(objv[2], (int *) NULL);
varPtr = TclLookupVar(interp, varName, (char *) NULL, /*flags*/ 0,
/*msg*/ 0, /*createPart1*/ 0, /*createPart2*/ 0, &arrayPtr);
notArray = 0;
if ((varPtr == NULL) || !TclIsVarArray(varPtr)
|| TclIsVarUndefined(varPtr)) {
notArray = 1;
}
switch (index) {
case 0: { /* anymore */
ArraySearch *searchPtr;
char *searchId;
if (objc != 4) {
Tcl_WrongNumArgs(interp, 2, objv,
"arrayName searchId");
return TCL_ERROR;
}
if (notArray) {
goto error;
}
searchId = Tcl_GetStringFromObj(objv[3], (int *) NULL);
searchPtr = ParseSearchId(interp, varPtr, varName, searchId);
if (searchPtr == NULL) {
return TCL_ERROR;
}
while (1) {
Var *varPtr2;
if (searchPtr->nextEntry != NULL) {
varPtr2 = (Var *) Tcl_GetHashValue(searchPtr->nextEntry);
if (!TclIsVarUndefined(varPtr2)) {
break;
}
}
searchPtr->nextEntry = Tcl_NextHashEntry(&searchPtr->search);
if (searchPtr->nextEntry == NULL) {
Tcl_SetIntObj(resultPtr, 0);
return TCL_OK;
}
}
Tcl_SetIntObj(resultPtr, 1);
break;
}
case 1: { /* donesearch */
ArraySearch *searchPtr, *prevPtr;
char *searchId;
if (objc != 4) {
Tcl_WrongNumArgs(interp, 2, objv,
"arrayName searchId");
return TCL_ERROR;
}
if (notArray) {
goto error;
}
searchId = Tcl_GetStringFromObj(objv[3], (int *) NULL);
searchPtr = ParseSearchId(interp, varPtr, varName, searchId);
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);
break;
}
case 2: { /* exists */
if (objc != 3) {
Tcl_WrongNumArgs(interp, 2, objv, "arrayName");
return TCL_ERROR;
}
Tcl_SetIntObj(resultPtr, !notArray);
break;
}
case 3: { /*get*/
Tcl_HashSearch search;
Var *varPtr2;
char *pattern = NULL;
char *name;
Tcl_Obj *namePtr, *valuePtr;
if ((objc != 3) && (objc != 4)) {
Tcl_WrongNumArgs(interp, 2, objv, "arrayName ?pattern?");
return TCL_ERROR;
}
if (notArray) {
return TCL_OK;
}
if (objc == 4) {
pattern = Tcl_GetStringFromObj(objv[3], (int *) NULL);
}
for (hPtr = Tcl_FirstHashEntry(varPtr->value.tablePtr, &search);
hPtr != NULL; hPtr = Tcl_NextHashEntry(&search)) {
varPtr2 = (Var *) Tcl_GetHashValue(hPtr);
if (TclIsVarUndefined(varPtr2)) {
continue;
}
name = Tcl_GetHashKey(varPtr->value.tablePtr, hPtr);
if ((objc == 4) && !Tcl_StringMatch(name, pattern)) {
continue; /* element name doesn't match pattern */
}
namePtr = Tcl_NewStringObj(name, -1);
result = Tcl_ListObjAppendElement(interp, resultPtr,
namePtr);
if (result != TCL_OK) {
Tcl_DecrRefCount(namePtr); /* free unneeded name obj */
return result;
}
valuePtr = Tcl_ObjGetVar2(interp, objv[2], namePtr,
TCL_LEAVE_ERR_MSG);
if (valuePtr == NULL) {
Tcl_DecrRefCount(namePtr); /* free unneeded name obj */
return result;
}
result = Tcl_ListObjAppendElement(interp, resultPtr,
valuePtr);
if (result != TCL_OK) {
Tcl_DecrRefCount(namePtr); /* free unneeded name obj */
return result;
}
}
break;
}
case 4: { /* names */
Tcl_HashSearch search;
Var *varPtr2;
char *pattern = NULL;
char *name;
Tcl_Obj *namePtr;
if ((objc != 3) && (objc != 4)) {
Tcl_WrongNumArgs(interp, 2, objv, "arrayName ?pattern?");
return TCL_ERROR;
}
if (notArray) {
return TCL_OK;
}
if (objc == 4) {
pattern = Tcl_GetStringFromObj(objv[3], (int *) NULL);
}
for (hPtr = Tcl_FirstHashEntry(varPtr->value.tablePtr, &search);
hPtr != NULL; hPtr = Tcl_NextHashEntry(&search)) {
varPtr2 = (Var *) Tcl_GetHashValue(hPtr);
if (TclIsVarUndefined(varPtr2)) {
continue;
}
name = Tcl_GetHashKey(varPtr->value.tablePtr, hPtr);
if ((objc == 4) && !Tcl_StringMatch(name, pattern)) {
continue; /* element name doesn't match pattern */
}
namePtr = Tcl_NewStringObj(name, -1);
result = Tcl_ListObjAppendElement(interp, resultPtr, namePtr);
if (result != TCL_OK) {
Tcl_DecrRefCount(namePtr); /* free unneeded name object */
return result;
}
}
break;
}
case 5: { /*nextelement*/
ArraySearch *searchPtr;
char *searchId;
Tcl_HashEntry *hPtr;
if (objc != 4) {
Tcl_WrongNumArgs(interp, 2, objv,
"arrayName searchId");
return TCL_ERROR;
}
if (notArray) {
goto error;
}
searchId = Tcl_GetStringFromObj(objv[3], (int *) NULL);
searchPtr = ParseSearchId(interp, varPtr, varName, searchId);
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 (!TclIsVarUndefined(varPtr2)) {
break;
}
}
Tcl_SetStringObj(resultPtr,
Tcl_GetHashKey(varPtr->value.tablePtr, hPtr), -1);
break;
}
case 6: { /*set*/
Tcl_Obj **elemPtrs;
int listLen, i, result;
if (objc != 4) {
Tcl_WrongNumArgs(interp, 2, objv, "arrayName list");
return TCL_ERROR;
}
result = Tcl_ListObjGetElements(interp, objv[3], &listLen,
&elemPtrs);
if (result != TCL_OK) {
return result;
}
if (listLen & 1) {
Tcl_ResetResult(interp);
Tcl_AppendToObj(Tcl_GetObjResult(interp),
"list must have an even number of elements", -1);
return TCL_ERROR;
}
if (listLen > 0) {
for (i = 0; i < listLen; i += 2) {
if (Tcl_ObjSetVar2(interp, objv[2], elemPtrs[i],
elemPtrs[i+1], TCL_LEAVE_ERR_MSG) == NULL) {
result = TCL_ERROR;
break;
}
}
} else if (varPtr == NULL) {
/*
* The list is empty and the array variable doesn't
* exist yet: create the variable with an empty array
* as the value.
*/
Tcl_Obj *namePtr, *valuePtr;
namePtr = Tcl_NewStringObj("tempElem", -1);
valuePtr = Tcl_NewObj();
if (Tcl_ObjSetVar2(interp, objv[2], namePtr, valuePtr,
/* flags*/ 0) == NULL) {
Tcl_DecrRefCount(namePtr);
Tcl_DecrRefCount(valuePtr);
return TCL_ERROR;
}
result = Tcl_UnsetVar2(interp, varName, "tempElem",
TCL_LEAVE_ERR_MSG);
if (result != TCL_OK) {
Tcl_DecrRefCount(namePtr);
Tcl_DecrRefCount(valuePtr);
return result;
}
}
return result;
}
case 7: { /*size*/
Tcl_HashSearch search;
Var *varPtr2;
int size;
if (objc != 3) {
Tcl_WrongNumArgs(interp, 2, objv, "arrayName");
return TCL_ERROR;
}
size = 0;
if (!notArray) {
for (hPtr = Tcl_FirstHashEntry(varPtr->value.tablePtr,
&search);
hPtr != NULL; hPtr = Tcl_NextHashEntry(&search)) {
varPtr2 = (Var *) Tcl_GetHashValue(hPtr);
if (TclIsVarUndefined(varPtr2)) {
continue;
}
size++;
}
}
Tcl_SetIntObj(resultPtr, size);
break;
}
case 8: { /*startsearch*/
ArraySearch *searchPtr;
if (objc != 3) {
Tcl_WrongNumArgs(interp, 2, objv, "arrayName");
return TCL_ERROR;
}
if (notArray) {
goto error;
}
searchPtr = (ArraySearch *) ckalloc(sizeof(ArraySearch));
if (varPtr->searchPtr == NULL) {
searchPtr->id = 1;
Tcl_AppendStringsToObj(resultPtr, "s-1-", varName,
(char *) NULL);
} else {
char string[20];
searchPtr->id = varPtr->searchPtr->id + 1;
TclFormatInt(string, searchPtr->id);
Tcl_AppendStringsToObj(resultPtr, "s-", string, "-", varName,
(char *) NULL);
}
searchPtr->varPtr = varPtr;
searchPtr->nextEntry = Tcl_FirstHashEntry(varPtr->value.tablePtr,
&searchPtr->search);
searchPtr->nextPtr = varPtr->searchPtr;
varPtr->searchPtr = searchPtr;
break;
}
}
return TCL_OK;
error:
Tcl_AppendStringsToObj(resultPtr, "\"", varName, "\" isn't an array",
(char *) NULL);
return TCL_ERROR;
}
/*
*----------------------------------------------------------------------
*
* MakeUpvar --
*
* This procedure does all of the work of the "global" and "upvar"
* commands.
*
* Results:
* A standard Tcl completion code. If an error occurs then an
* error message is left in iPtr->result.
*
* Side effects:
* The variable given by myName is linked to the variable in framePtr
* given by otherP1 and otherP2, so that references to myName are
* redirected to the other variable like a symbolic link.
*
*----------------------------------------------------------------------
*/
static int
MakeUpvar(iPtr, framePtr, otherP1, otherP2, otherFlags, myName, myFlags)
Interp *iPtr; /* Interpreter containing variables. Used
* for error messages, too. */
CallFrame *framePtr; /* Call frame containing "other" variable.
* NULL means use global :: context. */
char *otherP1, *otherP2; /* Two-part name of variable in framePtr. */
int otherFlags; /* 0, TCL_GLOBAL_ONLY or TCL_NAMESPACE_ONLY:
* indicates scope of "other" variable. */
char *myName; /* Name of variable which will refer to
* otherP1/otherP2. Must be a scalar. */
int myFlags; /* 0, TCL_GLOBAL_ONLY or TCL_NAMESPACE_ONLY:
* indicates scope of myName. */
{
Tcl_HashEntry *hPtr;
Var *otherPtr, *varPtr, *arrayPtr;
CallFrame *varFramePtr;
CallFrame *savedFramePtr = NULL; /* Init. to avoid compiler warning. */
Tcl_HashTable *tablePtr;
Namespace *nsPtr, *altNsPtr, *dummyNsPtr;
char *tail;
int new, result;
/*
* Find "other" in "framePtr". If not looking up other in just the
* current namespace, temporarily replace the current var frame
* pointer in the interpreter in order to use TclLookupVar.
*/
if (!(otherFlags & TCL_NAMESPACE_ONLY)) {
savedFramePtr = iPtr->varFramePtr;
iPtr->varFramePtr = framePtr;
}
otherPtr = TclLookupVar((Tcl_Interp *) iPtr, otherP1, otherP2,
(otherFlags | TCL_LEAVE_ERR_MSG), "access",
/*createPart1*/ 1, /*createPart2*/ 1, &arrayPtr);
if (!(otherFlags & TCL_NAMESPACE_ONLY)) {
iPtr->varFramePtr = savedFramePtr;
}
if (otherPtr == NULL) {
return TCL_ERROR;
}
/*
* Now create a hashtable entry for "myName". Create it as either a
* namespace variable or as a local variable in a procedure call
* frame. Interpret myName as a namespace variable if:
* 1) so requested by a TCL_GLOBAL_ONLY or TCL_NAMESPACE_ONLY flag,
* 2) there is no active frame (we're at the global :: scope),
* 3) the active frame was pushed to define the namespace context
* for a "namespace eval" or "namespace inscope" command,
* 4) the name has namespace qualifiers ("::"s).
* If creating myName in the active procedure, look first in the
* frame's array of compiler-allocated local variables, then in its
* hashtable for runtime-created local variables. Create that
* procedure's local variable hashtable if necessary.
*/
varFramePtr = iPtr->varFramePtr;
if ((myFlags & (TCL_GLOBAL_ONLY | TCL_NAMESPACE_ONLY))
|| (varFramePtr == NULL)
|| !varFramePtr->isProcCallFrame
|| (strstr(myName, "::") != NULL)) {
result = TclGetNamespaceForQualName((Tcl_Interp *) iPtr, myName,
(Namespace *) NULL, (myFlags | TCL_LEAVE_ERR_MSG),
&nsPtr, &altNsPtr, &dummyNsPtr, &tail);
if (result != TCL_OK) {
return result;
}
if (nsPtr == NULL) {
nsPtr = altNsPtr;
}
if (nsPtr == NULL) {
Tcl_AppendResult((Tcl_Interp *) iPtr, "bad variable name \"",
myName, "\": unknown namespace", (char *) NULL);
return TCL_ERROR;
}
/*
* Check that we are not trying to create a namespace var linked to
* a local variable in a procedure. If we allowed this, the local
* variable in the shorter-lived procedure frame could go away
* leaving the namespace var's reference invalid.
*/
if (otherPtr->nsPtr == NULL) {
Tcl_AppendResult((Tcl_Interp *) iPtr, "bad variable name \"",
myName, "\": upvar won't create namespace variable that refers to procedure variable",
(char *) NULL);
return TCL_ERROR;
}
hPtr = Tcl_CreateHashEntry(&nsPtr->varTable, tail, &new);
if (new) {
varPtr = NewVar();
Tcl_SetHashValue(hPtr, varPtr);
varPtr->hPtr = hPtr;
varPtr->nsPtr = nsPtr;
} else {
varPtr = (Var *) Tcl_GetHashValue(hPtr);
}
} else { /* look in the call frame */
Proc *procPtr = varFramePtr->procPtr;
int localCt = procPtr->numCompiledLocals;
CompiledLocal *localPtr = procPtr->firstLocalPtr;
Var *localVarPtr = varFramePtr->compiledLocals;
int nameLen = strlen(myName);
int i;
varPtr = NULL;
for (i = 0; i < localCt; i++) {
if (!localPtr->isTemp) {
char *localName = localVarPtr->name;
if ((myName[0] == localName[0])
&& (nameLen == localPtr->nameLength)
&& (strcmp(myName, localName) == 0)) {
varPtr = localVarPtr;
new = 0;
break;
}
}
localVarPtr++;
localPtr = localPtr->nextPtr;
}
if (varPtr == NULL) { /* look in frame's local var hashtable */
tablePtr = varFramePtr->varTablePtr;
if (tablePtr == NULL) {
tablePtr = (Tcl_HashTable *) ckalloc(sizeof(Tcl_HashTable));
Tcl_InitHashTable(tablePtr, TCL_STRING_KEYS);
varFramePtr->varTablePtr = tablePtr;
}
hPtr = Tcl_CreateHashEntry(tablePtr, myName, &new);
if (new) {
varPtr = NewVar();
Tcl_SetHashValue(hPtr, varPtr);
varPtr->hPtr = hPtr;
varPtr->nsPtr = varFramePtr->nsPtr;
} else {
varPtr = (Var *) Tcl_GetHashValue(hPtr);
}
}
}
if (!new) {
/*
* The variable already exists. Make sure this variable "varPtr"
* isn't the same as "otherPtr" (avoid circular links). Also, if
* it's not an upvar then it's an error. If it is an upvar, then
* just disconnect it from the thing it currently refers to.
*/
if (varPtr == otherPtr) {
Tcl_SetResult((Tcl_Interp *) iPtr,
"can't upvar from variable to itself", TCL_STATIC);
return TCL_ERROR;
}
if (TclIsVarLink(varPtr)) {
Var *linkPtr = varPtr->value.linkPtr;
if (linkPtr == otherPtr) {
return TCL_OK;
}
linkPtr->refCount--;
if (TclIsVarUndefined(linkPtr)) {
CleanupVar(linkPtr, (Var *) NULL);
}
} else if (!TclIsVarUndefined(varPtr)) {
Tcl_AppendResult((Tcl_Interp *) iPtr, "variable \"", myName,
"\" already exists", (char *) NULL);
return TCL_ERROR;
} else if (varPtr->tracePtr != NULL) {
Tcl_AppendResult((Tcl_Interp *) iPtr, "variable \"", myName,
"\" has traces: can't use for upvar", (char *) NULL);
return TCL_ERROR;
}
}
TclSetVarLink(varPtr);
TclClearVarUndefined(varPtr);
varPtr->value.linkPtr = otherPtr;
otherPtr->refCount++;
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_UpVar --
*
* This procedure links one variable to another, just like
* the "upvar" command.
*
* Results:
* A standard Tcl completion code. If an error occurs then
* an error message is left in interp->result.
*
* Side effects:
* The variable in frameName whose name is given by varName becomes
* accessible under the name localName, so that references to
* localName are redirected to the other variable like a symbolic
* link.
*
*----------------------------------------------------------------------
*/
int
Tcl_UpVar(interp, frameName, varName, localName, flags)
Tcl_Interp *interp; /* Command interpreter in which varName is
* to be looked up. */
char *frameName; /* Name of the frame containing the source
* variable, such as "1" or "#0". */
char *varName; /* Name of a variable in interp to link to.
* May be either a scalar name or an
* element in an array. */
char *localName; /* Name of link variable. */
int flags; /* 0, TCL_GLOBAL_ONLY or TCL_NAMESPACE_ONLY:
* indicates scope of localName. */
{
int result;
CallFrame *framePtr;
register char *p;
result = TclGetFrame(interp, frameName, &framePtr);
if (result == -1) {
return TCL_ERROR;
}
/*
* Figure out whether varName is an array reference, then call
* MakeUpvar to do all the real work.
*/
for (p = varName; *p != '\0'; p++) {
if (*p == '(') {
char *openParen = p;
do {
p++;
} while (*p != '\0');
p--;
if (*p != ')') {
goto scalar;
}
*openParen = '\0';
*p = '\0';
result = MakeUpvar((Interp *) interp, framePtr, varName,
openParen+1, 0, localName, flags);
*openParen = '(';
*p = ')';
return result;
}
}
scalar:
return MakeUpvar((Interp *) interp, framePtr, varName, (char *) NULL,
0, localName, flags);
}
/*
*----------------------------------------------------------------------
*
* Tcl_UpVar2 --
*
* This procedure links one variable to another, just like
* the "upvar" command.
*
* Results:
* A standard Tcl completion code. If an error occurs then
* an error message is left in interp->result.
*
* Side effects:
* The variable in frameName whose name is given by part1 and
* part2 becomes accessible under the name localName, so that
* references to localName are redirected to the other variable
* like a symbolic link.
*
*----------------------------------------------------------------------
*/
int
Tcl_UpVar2(interp, frameName, part1, part2, localName, flags)
Tcl_Interp *interp; /* Interpreter containing variables. Used
* for error messages too. */
char *frameName; /* Name of the frame containing the source
* variable, such as "1" or "#0". */
char *part1, *part2; /* Two parts of source variable name to
* link to. */
char *localName; /* Name of link variable. */
int flags; /* 0, TCL_GLOBAL_ONLY or TCL_NAMESPACE_ONLY:
* indicates scope of localName. */
{
int result;
CallFrame *framePtr;
result = TclGetFrame(interp, frameName, &framePtr);
if (result == -1) {
return TCL_ERROR;
}
return MakeUpvar((Interp *) interp, framePtr, part1, part2, 0,
localName, flags);
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetVariableFullName --
*
* Given a Tcl_Var token returned by Tcl_FindNamespaceVar, this
* procedure appends to an object the namespace variable's full
* name, qualified by a sequence of parent namespace names.
*
* Results:
* None.
*
* Side effects:
* The variable's fully-qualified name is appended to the string
* representation of objPtr.
*
*----------------------------------------------------------------------
*/
void
Tcl_GetVariableFullName(interp, variable, objPtr)
Tcl_Interp *interp; /* Interpreter containing the variable. */
Tcl_Var variable; /* Token for the variable returned by a
* previous call to Tcl_FindNamespaceVar. */
Tcl_Obj *objPtr; /* Points to the object onto which the
* variable's full name is appended. */
{
Interp *iPtr = (Interp *) interp;
register Var *varPtr = (Var *) variable;
char *name;
/*
* Add the full name of the containing namespace (if any), followed by
* the "::" separator, then the variable name.
*/
if (varPtr != NULL) {
if (!TclIsVarArrayElement(varPtr)) {
if (varPtr->nsPtr != NULL) {
Tcl_AppendToObj(objPtr, varPtr->nsPtr->fullName, -1);
if (varPtr->nsPtr != iPtr->globalNsPtr) {
Tcl_AppendToObj(objPtr, "::", 2);
}
}
if (varPtr->name != NULL) {
Tcl_AppendToObj(objPtr, varPtr->name, -1);
} else if (varPtr->hPtr != NULL) {
name = Tcl_GetHashKey(varPtr->hPtr->tablePtr, varPtr->hPtr);
Tcl_AppendToObj(objPtr, name, -1);
}
}
}
}
/*
*----------------------------------------------------------------------
*
* Tcl_GlobalObjCmd --
*
* This object-based procedure is invoked to process the "global" Tcl
* command. See the user documentation for details on what it does.
*
* Results:
* A standard Tcl object result value.
*
* Side effects:
* See the user documentation.
*
*----------------------------------------------------------------------
*/
int
Tcl_GlobalObjCmd(dummy, interp, objc, objv)
ClientData dummy; /* Not used. */
Tcl_Interp *interp; /* Current interpreter. */
int objc; /* Number of arguments. */
Tcl_Obj *CONST objv[]; /* Argument objects. */
{
Interp *iPtr = (Interp *) interp;
register Tcl_Obj *objPtr;
char *varName;
register char *tail;
int result, i;
if (objc < 2) {
Tcl_WrongNumArgs(interp, 1, objv, "varName ?varName ...?");
return TCL_ERROR;
}
/*
* If we are not executing inside a Tcl procedure, just return.
*/
if ((iPtr->varFramePtr == NULL)
|| !iPtr->varFramePtr->isProcCallFrame) {
return TCL_OK;
}
for (i = 1; i < objc; i++) {
/*
* Make a local variable linked to its counterpart in the global ::
* namespace.
*/
objPtr = objv[i];
varName = Tcl_GetStringFromObj(objPtr, (int *) NULL);
/*
* The variable name might have a scope qualifier, but the name for
* the local "link" variable must be the simple name at the tail.
*/
for (tail = varName; *tail != '\0'; tail++) {
/* empty body */
}
while ((tail > varName) && ((*tail != ':') || (*(tail-1) != ':'))) {
tail--;
}
if (*tail == ':') {
tail++;
}
/*
* Link to the variable "varName" in the global :: namespace.
*/
result = MakeUpvar(iPtr, (CallFrame *) NULL,
varName, (char *) NULL, /*otherFlags*/ TCL_GLOBAL_ONLY,
/*myName*/ tail, /*myFlags*/ 0);
if (result != TCL_OK) {
return result;
}
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_VariableObjCmd --
*
* Invoked to implement the "variable" command that creates one or more
* global variables. Handles the following syntax:
*
* variable ?name value...? name ?value?
*
* One or more variables can be created. The variables are initialized
* with the specified values. The value for the last variable is
* optional.
*
* If the variable does not exist, it is created and given the optional
* value. If it already exists, it is simply set to the optional
* value. Normally, "name" is an unqualified name, so it is created in
* the current namespace. If it includes namespace qualifiers, it can
* be created in another namespace.
*
* If the variable command is executed inside a Tcl procedure, it
* creates a local variable linked to the newly-created namespace
* variable.
*
* Results:
* Returns TCL_OK if the variable is found or created. Returns
* TCL_ERROR if anything goes wrong.
*
* Side effects:
* If anything goes wrong, this procedure returns an error message
* as the result in the interpreter's result object.
*
*----------------------------------------------------------------------
*/
int
Tcl_VariableObjCmd(dummy, interp, objc, objv)
ClientData dummy; /* Not used. */
Tcl_Interp *interp; /* Current interpreter. */
int objc; /* Number of arguments. */
Tcl_Obj *CONST objv[]; /* Argument objects. */
{
Interp *iPtr = (Interp *) interp;
char *varName, *tail;
Var *varPtr, *arrayPtr;
Tcl_Obj *varValuePtr;
int i, result;
for (i = 1; i < objc; i = i+2) {
/*
* Look up each variable in the current namespace context, creating
* it if necessary.
*/
varName = Tcl_GetStringFromObj(objv[i], (int *) NULL);
varPtr = TclLookupVar(interp, varName, (char *) NULL,
(TCL_NAMESPACE_ONLY | TCL_LEAVE_ERR_MSG), "define",
/*createPart1*/ 1, /*createPart2*/ 0, &arrayPtr);
if (varPtr == NULL) {
return TCL_ERROR;
}
/*
* Mark the variable as a namespace variable and increment its
* reference count so that it will persist until its namespace is
* destroyed or until the variable is unset.
*/
if (!(varPtr->flags & VAR_NAMESPACE_VAR)) {
varPtr->flags |= VAR_NAMESPACE_VAR;
varPtr->refCount++;
}
/*
* If a value was specified, set the variable to that value.
* Otherwise, if the variable is new, leave it undefined.
* (If the variable already exists and no value was specified,
* leave its value unchanged; just create the local link if
* we're in a Tcl procedure).
*/
if (i+1 < objc) { /* a value was specified */
varValuePtr = Tcl_ObjSetVar2(interp, objv[i], (Tcl_Obj *) NULL,
objv[i+1], (TCL_NAMESPACE_ONLY | TCL_LEAVE_ERR_MSG));
if (varValuePtr == NULL) {
return TCL_ERROR;
}
}
/*
* If we are executing inside a Tcl procedure, create a local
* variable linked to the new namespace variable "varName".
*/
if ((iPtr->varFramePtr != NULL)
&& iPtr->varFramePtr->isProcCallFrame) {
/*
* varName might have a scope qualifier, but the name for the
* local "link" variable must be the simple name at the tail.
*/
for (tail = varName; *tail != '\0'; tail++) {
/* empty body */
}
while ((tail > varName)
&& ((*tail != ':') || (*(tail-1) != ':'))) {
tail--;
}
if (*tail == ':') {
tail++;
}
/*
* Create a local link "tail" to the variable "varName" in the
* current namespace.
*/
result = MakeUpvar(iPtr, (CallFrame *) NULL,
/*otherP1*/ varName, /*otherP2*/ (char *) NULL,
/*otherFlags*/ TCL_NAMESPACE_ONLY,
/*myName*/ tail, /*myFlags*/ 0);
if (result != TCL_OK) {
return result;
}
}
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_UpvarObjCmd --
*
* This object-based procedure is invoked to process the "upvar"
* Tcl command. See the user documentation for details on what it does.
*
* Results:
* A standard Tcl object result value.
*
* Side effects:
* See the user documentation.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
int
Tcl_UpvarObjCmd(dummy, interp, objc, objv)
ClientData dummy; /* Not used. */
Tcl_Interp *interp; /* Current interpreter. */
int objc; /* Number of arguments. */
Tcl_Obj *CONST objv[]; /* Argument objects. */
{
register Interp *iPtr = (Interp *) interp;
CallFrame *framePtr;
char *frameSpec, *otherVarName, *myVarName;
register char *p;
int result;
if (objc < 3) {
upvarSyntax:
Tcl_WrongNumArgs(interp, 1, objv,
"?level? otherVar localVar ?otherVar localVar ...?");
return TCL_ERROR;
}
/*
* Find the call frame containing each of the "other variables" to be
* linked to. FAILS IF objv[1]'s STRING REP CONTAINS NULLS.
*/
frameSpec = Tcl_GetStringFromObj(objv[1], (int *) NULL);
result = TclGetFrame(interp, frameSpec, &framePtr);
if (result == -1) {
return TCL_ERROR;
}
objc -= result+1;
if ((objc & 1) != 0) {
goto upvarSyntax;
}
objv += result+1;
/*
* Iterate over each (other variable, local variable) pair.
* Divide the other variable name into two parts, then call
* MakeUpvar to do all the work of linking it to the local variable.
*/
for ( ; objc > 0; objc -= 2, objv += 2) {
myVarName = Tcl_GetStringFromObj(objv[1], (int *) NULL);
otherVarName = Tcl_GetStringFromObj(objv[0], (int *) NULL);
for (p = otherVarName; *p != 0; p++) {
if (*p == '(') {
char *openParen = p;
do {
p++;
} while (*p != '\0');
p--;
if (*p != ')') {
goto scalar;
}
*openParen = '\0';
*p = '\0';
result = MakeUpvar(iPtr, framePtr,
otherVarName, openParen+1, /*otherFlags*/ 0,
myVarName, /*flags*/ 0);
*openParen = '(';
*p = ')';
goto checkResult;
}
}
scalar:
result = MakeUpvar(iPtr, framePtr, otherVarName, (char *) NULL, 0,
myVarName, /*flags*/ 0);
checkResult:
if (result != TCL_OK) {
return TCL_ERROR;
}
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* 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-NULL 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, varPtr, part1, part2, 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. */
Var *varPtr; /* Variable whose traces are to be
* invoked. */
char *part1, *part2; /* Variable's two-part name. */
int flags; /* Flags passed to trace procedures:
* indicates what's happening to variable,
* plus other stuff like TCL_GLOBAL_ONLY,
* TCL_NAMESPACE_ONLY, and
* TCL_INTERP_DESTROYED. May also contain
* TCL_PARSE_PART1, which should not be
* passed through to callbacks. */
{
register VarTrace *tracePtr;
ActiveVarTrace active;
char *result, *openParen, *p;
Tcl_DString nameCopy;
int copiedName;
/*
* If there are already similar trace procedures active for the
* variable, don't call them again.
*/
if (varPtr->flags & VAR_TRACE_ACTIVE) {
return NULL;
}
varPtr->flags |= VAR_TRACE_ACTIVE;
varPtr->refCount++;
/*
* If the variable name hasn't been parsed into array name and
* element, do it here. If there really is an array element,
* make a copy of the original name so that NULLs can be
* inserted into it to separate the names (can't modify the name
* string in place, because the string might get used by the
* callbacks we invoke).
*/
copiedName = 0;
if (flags & TCL_PARSE_PART1) {
for (p = part1; ; p++) {
if (*p == 0) {
break;
}
if (*p == '(') {
openParen = p;
do {
p++;
} while (*p != '\0');
p--;
if (*p == ')') {
Tcl_DStringInit(&nameCopy);
Tcl_DStringAppend(&nameCopy, part1, (p-part1));
part2 = Tcl_DStringValue(&nameCopy)
+ (openParen + 1 - part1);
part2[-1] = 0;
part1 = Tcl_DStringValue(&nameCopy);
copiedName = 1;
}
break;
}
}
}
flags &= ~TCL_PARSE_PART1;
/*
* Invoke traces on the array containing the variable, if relevant.
*/
result = NULL;
active.nextPtr = iPtr->activeTracePtr;
iPtr->activeTracePtr = &active;
if (arrayPtr != NULL) {
arrayPtr->refCount++;
active.varPtr = arrayPtr;
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, part1, part2, 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;
}
active.varPtr = varPtr;
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, part1, part2, 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.
*/
done:
if (arrayPtr != NULL) {
arrayPtr->refCount--;
}
if (copiedName) {
Tcl_DStringFree(&nameCopy);
}
varPtr->flags &= ~VAR_TRACE_ACTIVE;
varPtr->refCount--;
iPtr->activeTracePtr = active.nextPtr;
return result;
}
/*
*----------------------------------------------------------------------
*
* NewVar --
*
* Create a new heap-allocated variable that will eventually be
* entered into a hashtable.
*
* Results:
* The return value is a pointer to the new variable structure. It is
* marked as a scalar variable (and not a link or array variable). Its
* value initially is NULL. The variable is not part of any hash table
* yet. Since it will be in a hashtable and not in a call frame, its
* name field is set NULL. It is initially marked as undefined.
*
* Side effects:
* Storage gets allocated.
*
*----------------------------------------------------------------------
*/
static Var *
NewVar()
{
register Var *varPtr;
varPtr = (Var *) ckalloc(sizeof(Var));
varPtr->value.objPtr = NULL;
varPtr->name = NULL;
varPtr->nsPtr = NULL;
varPtr->hPtr = NULL;
varPtr->refCount = 0;
varPtr->tracePtr = NULL;
varPtr->searchPtr = NULL;
varPtr->flags = (VAR_SCALAR | VAR_UNDEFINED | VAR_IN_HASHTABLE);
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);
}
}
/*
*----------------------------------------------------------------------
*
* 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
* variables 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_Interp *interp = (Tcl_Interp *) iPtr;
Tcl_HashSearch search;
Tcl_HashEntry *hPtr;
register Var *varPtr;
Var *linkPtr;
int flags;
ActiveVarTrace *activePtr;
Tcl_Obj *objPtr;
Namespace *currNsPtr = (Namespace *) Tcl_GetCurrentNamespace(interp);
/*
* Determine what flags to pass to the trace callback procedures.
*/
flags = TCL_TRACE_UNSETS;
if (tablePtr == &iPtr->globalNsPtr->varTable) {
flags |= (TCL_INTERP_DESTROYED | TCL_GLOBAL_ONLY);
} else if (tablePtr == &currNsPtr->varTable) {
flags |= TCL_NAMESPACE_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, decrement
* the reference count on the variable referred to, and free
* the referenced variable if it's no longer needed. Don't delete
* the hash entry for the other variable if it's in the same table
* as us: this will happen automatically later on.
*/
if (TclIsVarLink(varPtr)) {
linkPtr = varPtr->value.linkPtr;
linkPtr->refCount--;
if ((linkPtr->refCount == 0) && TclIsVarUndefined(linkPtr)
&& (linkPtr->tracePtr == NULL)
&& (linkPtr->flags & VAR_IN_HASHTABLE)) {
if (linkPtr->hPtr == NULL) {
ckfree((char *) linkPtr);
} else if (linkPtr->hPtr->tablePtr != tablePtr) {
Tcl_DeleteHashEntry(linkPtr->hPtr);
ckfree((char *) linkPtr);
}
}
}
/*
* 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). Note that we give CallTraces the variable's
* fully-qualified name so that any called trace procedures can
* refer to these variables being deleted.
*/
if (varPtr->tracePtr != NULL) {
objPtr = Tcl_NewObj();
Tcl_IncrRefCount(objPtr); /* until done with traces */
Tcl_GetVariableFullName(interp, (Tcl_Var) varPtr, objPtr);
(void) CallTraces(iPtr, (Var *) NULL, varPtr,
Tcl_GetStringFromObj(objPtr, (int *) NULL),
(char *) NULL, flags);
Tcl_DecrRefCount(objPtr); /* free no longer needed obj */
while (varPtr->tracePtr != NULL) {
VarTrace *tracePtr = varPtr->tracePtr;
varPtr->tracePtr = tracePtr->nextPtr;
ckfree((char *) tracePtr);
}
for (activePtr = iPtr->activeTracePtr; activePtr != NULL;
activePtr = activePtr->nextPtr) {
if (activePtr->varPtr == varPtr) {
activePtr->nextTracePtr = NULL;
}
}
}
if (TclIsVarArray(varPtr)) {
DeleteArray(iPtr, Tcl_GetHashKey(tablePtr, hPtr), varPtr,
flags);
}
if (TclIsVarScalar(varPtr) && (varPtr->value.objPtr != NULL)) {
objPtr = varPtr->value.objPtr;
TclDecrRefCount(objPtr);
varPtr->value.objPtr = NULL;
}
varPtr->hPtr = NULL;
varPtr->tracePtr = NULL;
TclSetVarUndefined(varPtr);
TclSetVarScalar(varPtr);
/*
* If the variable was a namespace variable, decrement its
* reference count. We are in the process of destroying its
* namespace so that namespace will no longer "refer" to the
* variable.
*/
if (varPtr->flags & VAR_NAMESPACE_VAR) {
varPtr->flags &= ~VAR_NAMESPACE_VAR;
varPtr->refCount--;
}
/*
* Recycle the variable's memory space if there aren't any upvar's
* pointing to it. If there are upvars to this variable, then the
* variable will get freed when the last upvar goes away.
*/
if (varPtr->refCount == 0) {
ckfree((char *) varPtr); /* this Var must be VAR_IN_HASHTABLE */
}
}
Tcl_DeleteHashTable(tablePtr);
}
/*
*----------------------------------------------------------------------
*
* TclDeleteCompiledLocalVars --
*
* This procedure is called to recycle storage space associated with
* the compiler-allocated array of local variables in a procedure call
* frame. This procedure resembles TclDeleteVars above except that each
* variable is stored in a call frame and not a hash table. 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
TclDeleteCompiledLocalVars(iPtr, framePtr)
Interp *iPtr; /* Interpreter to which variables belong. */
CallFrame *framePtr; /* Procedure call frame containing
* compiler-assigned local variables to
* delete. */
{
register Var *varPtr;
int flags; /* Flags passed to trace procedures. */
Var *linkPtr;
ActiveVarTrace *activePtr;
int numLocals, i;
flags = TCL_TRACE_UNSETS;
numLocals = framePtr->numCompiledLocals;
varPtr = framePtr->compiledLocals;
for (i = 0; i < numLocals; i++) {
/*
* For global/upvar variables referenced in procedures, decrement
* the reference count on the variable referred to, and free
* the referenced variable if it's no longer needed. Don't delete
* the hash entry for the other variable if it's in the same table
* as us: this will happen automatically later on.
*/
if (TclIsVarLink(varPtr)) {
linkPtr = varPtr->value.linkPtr;
linkPtr->refCount--;
if ((linkPtr->refCount == 0) && TclIsVarUndefined(linkPtr)
&& (linkPtr->tracePtr == NULL)
&& (linkPtr->flags & VAR_IN_HASHTABLE)) {
if (linkPtr->hPtr == NULL) {
ckfree((char *) linkPtr);
} else {
Tcl_DeleteHashEntry(linkPtr->hPtr);
ckfree((char *) linkPtr);
}
}
}
/*
* Invoke traces on the variable that is being deleted. Then delete
* the variable's trace records.
*/
if (varPtr->tracePtr != NULL) {
(void) CallTraces(iPtr, (Var *) NULL, varPtr,
varPtr->name, (char *) NULL, flags);
while (varPtr->tracePtr != NULL) {
VarTrace *tracePtr = varPtr->tracePtr;
varPtr->tracePtr = tracePtr->nextPtr;
ckfree((char *) tracePtr);
}
for (activePtr = iPtr->activeTracePtr; activePtr != NULL;
activePtr = activePtr->nextPtr) {
if (activePtr->varPtr == varPtr) {
activePtr->nextTracePtr = NULL;
}
}
}
/*
* Now if the variable is an array, delete its element hash table.
* Otherwise, if it's a scalar variable, decrement the ref count
* of its value.
*/
if (TclIsVarArray(varPtr) && (varPtr->value.tablePtr != NULL)) {
DeleteArray(iPtr, varPtr->name, varPtr, flags);
}
if (TclIsVarScalar(varPtr) && (varPtr->value.objPtr != NULL)) {
TclDecrRefCount(varPtr->value.objPtr);
varPtr->value.objPtr = NULL;
}
varPtr->hPtr = NULL;
varPtr->tracePtr = NULL;
TclSetVarUndefined(varPtr);
TclSetVarScalar(varPtr);
varPtr++;
}
}
/*
*----------------------------------------------------------------------
*
* 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 array's hash table). Deletion trace procedures for
* array elements are invoked, then deleted. Any pending traces for
* array elements are also deleted.
*
*----------------------------------------------------------------------
*/
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,
* TCL_NAMESPACE_ONLY, or
* TCL_GLOBAL_ONLY. */
{
Tcl_HashSearch search;
register Tcl_HashEntry *hPtr;
register Var *elPtr;
ActiveVarTrace *activePtr;
Tcl_Obj *objPtr;
DeleteSearches(varPtr);
for (hPtr = Tcl_FirstHashEntry(varPtr->value.tablePtr, &search);
hPtr != NULL; hPtr = Tcl_NextHashEntry(&search)) {
elPtr = (Var *) Tcl_GetHashValue(hPtr);
if (TclIsVarScalar(elPtr) && (elPtr->value.objPtr != NULL)) {
objPtr = elPtr->value.objPtr;
TclDecrRefCount(objPtr);
elPtr->value.objPtr = NULL;
}
elPtr->hPtr = NULL;
if (elPtr->tracePtr != NULL) {
elPtr->flags &= ~VAR_TRACE_ACTIVE;
(void) CallTraces(iPtr, (Var *) NULL, elPtr, arrayName,
Tcl_GetHashKey(varPtr->value.tablePtr, hPtr), flags);
while (elPtr->tracePtr != NULL) {
VarTrace *tracePtr = elPtr->tracePtr;
elPtr->tracePtr = tracePtr->nextPtr;
ckfree((char *) tracePtr);
}
for (activePtr = iPtr->activeTracePtr; activePtr != NULL;
activePtr = activePtr->nextPtr) {
if (activePtr->varPtr == elPtr) {
activePtr->nextTracePtr = NULL;
}
}
}
TclSetVarUndefined(elPtr);
TclSetVarScalar(elPtr);
if (elPtr->refCount == 0) {
ckfree((char *) elPtr); /* element Vars are VAR_IN_HASHTABLE */
}
}
Tcl_DeleteHashTable(varPtr->value.tablePtr);
ckfree((char *) varPtr->value.tablePtr);
}
/*
*----------------------------------------------------------------------
*
* CleanupVar --
*
* This procedure is called when it looks like it may be OK to free up
* a variable's storage. If the variable is in a hashtable, its Var
* structure and hash table entry will be freed along with those of its
* containing array, if any. This procedure is called, for example,
* when a trace on a variable deletes a variable.
*
* Results:
* None.
*
* Side effects:
* If the variable (or its containing array) really is dead and in a
* hashtable, then its Var structure, and possibly its hash table
* entry, is freed up.
*
*----------------------------------------------------------------------
*/
static void
CleanupVar(varPtr, arrayPtr)
Var *varPtr; /* Pointer to variable that may be a
* candidate for being expunged. */
Var *arrayPtr; /* Array that contains the variable, or
* NULL if this variable isn't an array
* element. */
{
if (TclIsVarUndefined(varPtr) && (varPtr->refCount == 0)
&& (varPtr->tracePtr == NULL)
&& (varPtr->flags & VAR_IN_HASHTABLE)) {
if (varPtr->hPtr != NULL) {
Tcl_DeleteHashEntry(varPtr->hPtr);
}
ckfree((char *) varPtr);
}
if (arrayPtr != NULL) {
if (TclIsVarUndefined(arrayPtr) && (arrayPtr->refCount == 0)
&& (arrayPtr->tracePtr == NULL)
&& (arrayPtr->flags & VAR_IN_HASHTABLE)) {
if (arrayPtr->hPtr != NULL) {
Tcl_DeleteHashEntry(arrayPtr->hPtr);
}
ckfree((char *) arrayPtr);
}
}
}
/*
*----------------------------------------------------------------------
*
* 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 part1 and part2 and describing why the
* variable operation failed.
*
*----------------------------------------------------------------------
*/
static void
VarErrMsg(interp, part1, part2, operation, reason)
Tcl_Interp *interp; /* Interpreter in which to record message. */
char *part1, *part2; /* 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, " \"", part1,
(char *) NULL);
if (part2 != NULL) {
Tcl_AppendResult(interp, "(", part2, ")", (char *) NULL);
}
Tcl_AppendResult(interp, "\": ", reason, (char *) NULL);
}