/// <summary> TclLookupVar -> lookupVar
///
/// This procedure is used by virtually all of the variable
/// code to locate a variable given its name(s).
///
/// </summary>
/// <param name="part1">if part2 isn't NULL, this is the name of an array.
/// Otherwise, this is a full variable name that could include
/// a parenthesized array elemnt or a scalar.
/// </param>
/// <param name="part2">Name of an element within array, or null.
/// </param>
/// <param name="flags">Only the TCL.VarFlag.GLOBAL_ONLY bit matters.
/// </param>
/// <param name="msg">Verb to use in error messages, e.g. "read" or "set".
/// </param>
/// <param name="create">OR'ed combination of CRT_PART1 and CRT_PART2.
/// Tells which entries to create if they don't already exist.
/// </param>
/// <param name="throwException">true if an exception should be throw if the
/// variable cannot be found.
/// </param>
/// <returns> a two element array. a[0] is the variable indicated by
/// part1 and part2, or null if the variable couldn't be
/// found and throwException is false.
/// <p>
/// If the variable is found, a[1] is 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 true, a new as-yet-undefined (VAR_UNDEFINED)
/// variable instance is created, entered into a hash
/// table, and returned.
/// Note: it's possible that var.value of the returned variable
/// may be null (variable undefined), even if createPart1 or createPart2
/// are true (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 by a trace.
/// </returns>
/// <exception cref=""> TclException if the variable cannot be found and
/// throwException is true.
///
/// </exception>
internal static Var[] lookupVar( Interp interp, string part1, string part2, TCL.VarFlag flags, string msg, bool createPart1, bool createPart2 )
{
CallFrame varFrame = interp.varFrame;
// Reference 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.
Hashtable table; // to the hashtable, if any, in which
// to look up the variable.
Var var; // Used to search for global names.
string elName; // Name of array element or null.
int openParen;
// If this procedure parses a name into
// array and index, these point to the
// parens around the index. Otherwise they
// are -1. These are needed to restore
// the parens after parsing the name.
NamespaceCmd.Namespace varNs, cxtNs;
int p;
int i, result;
var = null;
openParen = -1;
varNs = null; // set non-null if a nonlocal variable
// Parse part1 into array name and index.
// Always check if part1 is an array element name and allow it only if
// part2 is not given.
// (if one does not care about creating array elements that can't be used
// from tcl, and prefer slightly better performance, one can put
// the following in an if (part2 == null) { ... } block and remove
// the part2's test and error reporting or move that code in array set)
elName = part2;
int len = part1.Length;
for ( p = 0; p < len; p++ )
{
if ( part1[p] == '(' )
{
openParen = p;
p = len - 1;
if ( part1[p] == ')' )
{
if ( (System.Object)part2 != null )
{
if ( ( flags & TCL.VarFlag.LEAVE_ERR_MSG ) != 0 )
{
throw new TclVarException( interp, part1, part2, msg, needArray );
}
return null;
}
elName = part1.Substring( openParen + 1, ( len - 1 ) - ( openParen + 1 ) );
part2 = elName; // same as elName, only used in error reporting
part1 = part1.Substring( 0, ( openParen ) - ( 0 ) );
}
break;
}
}
// If this namespace has a variable resolver, then give it first
// crack at the variable resolution. It may return a Var
// value, it may signal to continue onward, or it may signal
// an error.
if ( ( ( flags & TCL.VarFlag.GLOBAL_ONLY ) != 0 ) || ( interp.varFrame == null ) )
{
cxtNs = interp.globalNs;
}
else
{
cxtNs = interp.varFrame.ns;
}
if ( cxtNs.resolver != null || interp.resolvers != null )
{
try
{
if ( cxtNs.resolver != null )
{
var = cxtNs.resolver.resolveVar( interp, part1, cxtNs, flags );
}
else
{
var = null;
}
if ( var == null && interp.resolvers != null )
{
IEnumerator enum_Renamed = interp.resolvers.GetEnumerator();
foreach ( Interp.ResolverScheme res in interp.resolvers )
{
var = res.resolver.resolveVar( interp, part1, cxtNs, flags );
if ( var != null )
break;
}
}
}
catch ( TclException e )
{
var = null;
}
}
// Look up part1. Look it up as either a namespace variable or as a
// local variable in a procedure call frame (varFrame).
// Interpret part1 as a namespace variable if:
// 1) so requested by a TCL.VarFlag.GLOBAL_ONLY or TCL.VarFlag.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 varFrame's local var hashtable.
if ( ( ( flags & ( TCL.VarFlag.GLOBAL_ONLY | TCL.VarFlag.NAMESPACE_ONLY ) ) != 0 ) || ( varFrame == null ) || !varFrame.isProcCallFrame || ( part1.IndexOf( "::" ) != -1 ) )
{
string tail;
// Don't pass TCL.VarFlag.LEAVE_ERR_MSG, we may yet create the variable,
// or otherwise generate our own error!
var = NamespaceCmd.findNamespaceVar( interp, part1, null, flags & ~TCL.VarFlag.LEAVE_ERR_MSG );
if ( var == null )
{
if ( createPart1 )
{
// var wasn't found so create it
// Java does not support passing an address so we pass
// an array of size 1 and then assign arr[0] to the value
NamespaceCmd.Namespace[] varNsArr = new NamespaceCmd.Namespace[1];
NamespaceCmd.Namespace[] dummyArr = new NamespaceCmd.Namespace[1];
string[] tailArr = new string[1];
NamespaceCmd.getNamespaceForQualName( interp, part1, null, flags, varNsArr, dummyArr, dummyArr, tailArr );
// Get the values out of the arrays!
varNs = varNsArr[0];
tail = tailArr[0];
if ( varNs == null )
{
if ( ( flags & TCL.VarFlag.LEAVE_ERR_MSG ) != 0 )
{
throw new TclVarException( interp, part1, part2, msg, badNamespace );
}
return null;
}
if ( (System.Object)tail == null )
{
if ( ( flags & TCL.VarFlag.LEAVE_ERR_MSG ) != 0 )
{
throw new TclVarException( interp, part1, part2, msg, missingName );
}
return null;
}
var = new Var();
varNs.varTable.Add( tail, var );
// There is no hPtr member in Jacl, The hPtr combines the table
// and the key used in a table lookup.
var.hashKey = tail;
var.table = varNs.varTable;
var.ns = varNs;
}
else
{
// var wasn't found and not to create it
if ( ( flags & TCL.VarFlag.LEAVE_ERR_MSG ) != 0 )
{
throw new TclVarException( interp, part1, part2, msg, noSuchVar );
}
return null;
}
}
}
else
{
// local var: look in frame varFrame
// removed code block that searches for local compiled vars
if ( var == null )
{
// look in the frame's var hash table
table = varFrame.varTable;
if ( createPart1 )
{
if ( table == null )
{
table = new Hashtable();
varFrame.varTable = table;
}
var = (Var)table[part1];
if ( var == null )
{
// we are adding a new entry
var = new Var();
SupportClass.PutElement( table, part1, var );
// There is no hPtr member in Jacl, The hPtr combines
// the table and the key used in a table lookup.
var.hashKey = part1;
var.table = table;
var.ns = null; // a local variable
}
}
else
{
if ( table != null )
{
var = (Var)table[part1];
}
if ( var == null )
{
if ( ( flags & TCL.VarFlag.LEAVE_ERR_MSG ) != 0 )
{
throw new TclVarException( interp, part1, part2, msg, noSuchVar );
}
return null;
}
}
}
}
// If var 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 ( var.isVarLink() )
{
var = (Var)var.value;
}
// If we're not dealing with an array element, return var.
if ( (System.Object)elName == null )
{
var ret = new Var[2];
ret[0] = var;
ret[1] = null;
return ret;
}
// 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 ( var.isVarUndefined() && !var.isVarArrayElement() )
{
if ( !createPart1 )
{
if ( ( flags & TCL.VarFlag.LEAVE_ERR_MSG ) != 0 )
{
throw new TclVarException( interp, part1, part2, msg, noSuchVar );
}
return null;
}
// Make sure we are not resurrecting a namespace variable from a
// deleted namespace!
if ( ( ( var.flags & VarFlags.IN_HASHTABLE ) != 0 ) && ( var.table == null ) )
{
if ( ( flags & TCL.VarFlag.LEAVE_ERR_MSG ) != 0 )
{
throw new TclVarException( interp, part1, part2, msg, danglingVar );
}
return null;
}
var.setVarArray();
var.clearVarUndefined();
var.value = new Hashtable();
}
else if ( !var.isVarArray() )
{
if ( ( flags & TCL.VarFlag.LEAVE_ERR_MSG ) != 0 )
{
throw new TclVarException( interp, part1, part2, msg, needArray );
}
return null;
}
Var arrayVar = var;
Hashtable arrayTable = (Hashtable)var.value;
if ( createPart2 )
{
Var searchvar = (Var)arrayTable[elName];
if ( searchvar == null )
{
// new entry
if ( var.sidVec != null )
{
deleteSearches( var );
}
var = new Var();
SupportClass.PutElement( arrayTable, elName, var );
// There is no hPtr member in Jacl, The hPtr combines the table
// and the key used in a table lookup.
var.hashKey = elName;
var.table = arrayTable;
var.ns = varNs;
var.setVarArrayElement();
}
else
{
var = searchvar;
}
}
else
{
var = (Var)arrayTable[elName];
if ( var == null )
{
if ( ( flags & TCL.VarFlag.LEAVE_ERR_MSG ) != 0 )
{
throw new TclVarException( interp, part1, part2, msg, noSuchElement );
}
return null;
}
}
var ret2 = new Var[2];
ret2[0] = var; // The Var in the array
ret2[1] = arrayVar; // The array (Hashtable) Var
return ret2;
}
/// <summary> DeleteArray -> 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.
///
/// </summary>
/// <param name="interp">Interpreter containing array.
/// </param>
/// <param name="arrayName">name of array (used for trace callbacks).
/// </param>
/// <param name="var">the array variable to delete.
/// </param>
/// <param name="flags">Flags to pass to CallTraces.
/// </param>
static protected internal void deleteArray( Interp interp, string arrayName, Var var, TCL.VarFlag flags )
{
IEnumerator search;
Var el;
TclObject obj;
deleteSearches( var );
Hashtable table = (Hashtable)var.value;
Var dummyVar;
for ( search = table.Values.GetEnumerator(); search.MoveNext(); )
{
el = (Var)search.Current;
if ( el.isVarScalar() && ( el.value != null ) )
{
obj = (TclObject)el.value;
obj.release();
el.value = null;
}
string tmpkey = (string)el.hashKey;
// There is no hPtr member in Jacl, The hPtr combines the table
// and the key used in a table lookup.
el.hashKey = null;
el.table = null;
if ( el.traces != null )
{
el.flags &= ~VarFlags.TRACE_ACTIVE;
// FIXME : Old Jacl impl passed a dummy var to callTraces, should we?
callTraces( interp, null, el, arrayName, tmpkey, flags );
el.traces = null;
// Active trace stuff is not part of Jacl
}
el.setVarUndefined();
el.setVarScalar();
if ( el.refCount == 0 )
{
// We are no longer using the element
// element Vars are IN_HASHTABLE
}
}
( (Hashtable)var.value ).Clear();
var.value = null;
}
/// <summary> CleanupVar -> cleanupVar
///
/// This procedure is called when it looks like it may be OK
/// to free up the variable's record and hash table entry, and
/// those of its containing parent. It's called, for example,
/// when a trace on a variable deletes the variable.
///
/// </summary>
/// <param name="var">variable that may be a candidate for being expunged.
/// </param>
/// <param name="array">Array that contains the variable, or NULL if this
/// variable isn't an array element.
/// </param>
static protected internal void cleanupVar( Var var, Var array )
{
if ( var.isVarUndefined() && ( var.refCount == 0 ) && ( var.traces == null ) && ( ( var.flags & VarFlags.IN_HASHTABLE ) != 0 ) )
{
if ( var.table != null )
{
SupportClass.HashtableRemove( var.table, var.hashKey );
var.table = null;
var.hashKey = null;
}
}
if ( array != null )
{
if ( array.isVarUndefined() && ( array.refCount == 0 ) && ( array.traces == null ) && ( ( array.flags & VarFlags.IN_HASHTABLE ) != 0 ) )
{
if ( array.table != null )
{
SupportClass.HashtableRemove( array.table, array.hashKey );
array.table = null;
array.hashKey = null;
}
}
}
}
/// <summary> DeleteSearches -> deleteSearches
///
/// This procedure is called to free up all of the searches
/// associated with an array variable.
///
/// </summary>
/// <param name="interp">Interpreter containing array.
/// </param>
/// <param name="arrayVar">the array variable to delete searches from.
/// </param>
static protected internal void deleteSearches( Var arrayVar )
// Variable whose searches are to be deleted.
{
arrayVar.sidVec = null;
}
/// <summary> CallTraces -> 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).
///
/// </summary>
/// <param name="interp">Interpreter containing variable.
/// </param>
/// <param name="array">array variable that contains the variable, or null
/// if the variable isn't an element of an array.
/// </param>
/// <param name="var">Variable whose traces are to be invoked.
/// </param>
/// <param name="part1">the first part of a variable name.
/// </param>
/// <param name="part2">the second part of a variable name.
/// </param>
/// <param name="flags">Flags to pass to trace procedures: indicates
/// what's happening to variable, plus other stuff like
/// TCL.VarFlag.GLOBAL_ONLY, TCL.VarFlag.NAMESPACE_ONLY, and TCL.VarFlag.INTERP_DESTROYED.
/// </param>
/// <returns> 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 string describing the error.
/// </returns>
static protected internal string callTraces( Interp interp, Var array, Var var, string part1, string part2, TCL.VarFlag flags )
{
TclObject oldResult;
int i;
// If there are already similar trace procedures active for the
// variable, don't call them again.
if ( ( var.flags & VarFlags.TRACE_ACTIVE ) != 0 )
{
return null;
}
var.flags |= VarFlags.TRACE_ACTIVE;
var.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).
// FIXME : come up with parsing code to use for all situations!
if ( (System.Object)part2 == null )
{
int len = part1.Length;
if ( len > 0 )
{
if ( part1[len - 1] == ')' )
{
for ( i = 0; i < len - 1; i++ )
{
if ( part1[i] == '(' )
{
break;
}
}
if ( i < len - 1 )
{
if ( i < len - 2 )
{
part2 = part1.Substring( i + 1, ( len - 1 ) - ( i + 1 ) );
part1 = part1.Substring( 0, ( i ) - ( 0 ) );
}
}
}
}
}
oldResult = interp.getResult();
oldResult.preserve();
interp.resetResult();
try
{
// Invoke traces on the array containing the variable, if relevant.
if ( array != null )
{
array.refCount++;
}
if ( ( array != null ) && ( array.traces != null ) )
{
for ( i = 0; ( array.traces != null ) && ( i < array.traces.Count ); i++ )
{
TraceRecord rec = (TraceRecord)array.traces[i];
if ( ( rec.flags & flags ) != 0 )
{
try
{
rec.trace.traceProc( interp, part1, part2, flags );
}
catch ( TclException e )
{
if ( ( flags & TCL.VarFlag.TRACE_UNSETS ) == 0 )
{
return interp.getResult().ToString();
}
}
}
}
}
// Invoke traces on the variable itself.
if ( ( flags & TCL.VarFlag.TRACE_UNSETS ) != 0 )
{
flags |= TCL.VarFlag.TRACE_DESTROYED;
}
for ( i = 0; ( var.traces != null ) && ( i < var.traces.Count ); i++ )
{
TraceRecord rec = (TraceRecord)var.traces[i];
if ( ( rec.flags & flags ) != 0 )
{
try
{
rec.trace.traceProc( interp, part1, part2, flags );
}
catch ( TclException e )
{
if ( ( flags & TCL.VarFlag.TRACE_UNSETS ) == 0 )
{
return interp.getResult().ToString();
}
}
}
}
return null;
}
finally
{
if ( array != null )
{
array.refCount--;
}
var.flags &= ~VarFlags.TRACE_ACTIVE;
var.refCount--;
interp.setResult( oldResult );
oldResult.release();
}
}
/*
*----------------------------------------------------------------------
*
* TCL.Tcl_GetVariableFullName -> getVariableFullName
*
* Given a Var token returned by NamespaceCmd.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 returned.
*
*----------------------------------------------------------------------
*/
internal static string getVariableFullName( Interp interp, Var var )
{
StringBuilder buff = new StringBuilder();
// Add the full name of the containing namespace (if any), followed by
// the "::" separator, then the variable name.
if ( var != null )
{
if ( !var.isVarArrayElement() )
{
if ( var.ns != null )
{
buff.Append( var.ns.fullName );
if ( var.ns != interp.globalNs )
{
buff.Append( "::" );
}
}
// Jacl's Var class does not include the "name" member
// We use the "hashKey" member which is equivalent
if ( (System.Object)var.hashKey != null )
{
buff.Append( var.hashKey );
}
}
}
return buff.ToString();
}
/// <summary> MakeUpvar -> makeUpvar
///
/// Create a reference of a variable in otherFrame in the current
/// CallFrame, given a two-part name consisting of array name and
/// element within array.
///
/// </summary>
/// <param name="interp">Interp containing the variables
/// </param>
/// <param name="frame">CallFrame containing "other" variable.
/// null means use global context.
/// </param>
/// <param name="otherP1">the 1st part name of the variable in the "other" frame.
/// </param>
/// <param name="otherP2">the 2nd part name of the variable in the "other" frame.
/// </param>
/// <param name="otherFlags">the flags for scaope of "other" variable
/// </param>
/// <param name="myName">Name of scalar variable which will refer to otherP1/otherP2.
/// </param>
/// <param name="myFlags">only the TCL.VarFlag.GLOBAL_ONLY bit matters,
/// indicating the scope of myName.
/// </param>
/// <exception cref=""> TclException if the upvar cannot be created.
/// </exception>
protected internal static void makeUpvar( Interp interp, CallFrame frame, string otherP1, string otherP2, TCL.VarFlag otherFlags, string myName, TCL.VarFlag myFlags )
{
Var other, var, array;
Var[] result;
CallFrame varFrame;
CallFrame savedFrame = null;
Hashtable table;
NamespaceCmd.Namespace ns, altNs;
string tail;
bool newvar = false;
// Find "other" in "frame". 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.VarFlag.NAMESPACE_ONLY ) == 0 )
{
savedFrame = interp.varFrame;
interp.varFrame = frame;
}
result = lookupVar( interp, otherP1, otherP2, ( otherFlags | TCL.VarFlag.LEAVE_ERR_MSG ), "access", true, true );
if ( ( otherFlags & TCL.VarFlag.NAMESPACE_ONLY ) == 0 )
{
interp.varFrame = savedFrame;
}
other = result[0];
array = result[1];
if ( other == null )
{
// FIXME : leave error message thing again
throw new TclRuntimeError( "unexpected null reference" );
}
// 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.VarFlag.GLOBAL_ONLY or TCL.VarFlag.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 in its
// hashtable for runtime-created local variables. Create that
// procedure's local variable hashtable if necessary.
varFrame = interp.varFrame;
if ( ( ( myFlags & ( TCL.VarFlag.GLOBAL_ONLY | TCL.VarFlag.NAMESPACE_ONLY ) ) != 0 ) || ( varFrame == null ) || !varFrame.isProcCallFrame || ( myName.IndexOf( "::" ) != -1 ) )
{
// Java does not support passing an address so we pass
// an array of size 1 and then assign arr[0] to the value
NamespaceCmd.Namespace[] nsArr = new NamespaceCmd.Namespace[1];
NamespaceCmd.Namespace[] altNsArr = new NamespaceCmd.Namespace[1];
NamespaceCmd.Namespace[] dummyNsArr = new NamespaceCmd.Namespace[1];
string[] tailArr = new string[1];
NamespaceCmd.getNamespaceForQualName( interp, myName, null, myFlags, nsArr, altNsArr, dummyNsArr, tailArr );
// Get the values out of the arrays!
ns = nsArr[0];
altNs = altNsArr[0];
tail = tailArr[0];
if ( ns == null )
{
ns = altNs;
}
if ( ns == null )
{
throw new TclException( interp, "bad variable name \"" + myName + "\": unknown namespace" );
}
// 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 ( ( ( (System.Object)otherP2 != null ) ? array.ns : other.ns ) == null )
{
throw new TclException( interp, "bad variable name \"" + myName + "\": upvar won't create namespace variable that refers to procedure variable" );
}
// AKT var = (Var) ns.varTable.get(tail);
var = (Var)ns.varTable[tail];
if ( var == null )
{
// we are adding a new entry
newvar = true;
var = new Var();
// ATK ns.varTable.put(tail, var);
ns.varTable.Add( tail, var );
// There is no hPtr member in Jacl, The hPtr combines the table
// and the key used in a table lookup.
var.hashKey = tail;
var.table = ns.varTable;
var.ns = ns;
}
}
else
{
// Skip Compiled Local stuff
var = null;
if ( var == null )
{
// look in frame's local var hashtable
table = varFrame.varTable;
if ( table == null )
{
table = new Hashtable();
varFrame.varTable = table;
}
var = (Var)table[myName];
if ( var == null )
{
// we are adding a new entry
newvar = true;
var = new Var();
SupportClass.PutElement( table, myName, var );
// There is no hPtr member in Jacl, The hPtr combines the table
// and the key used in a table lookup.
var.hashKey = myName;
var.table = table;
var.ns = varFrame.ns;
}
}
}
if ( !newvar )
{
// The variable already exists. Make sure this variable "var"
// isn't the same as "other" (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 ( var == other )
{
throw new TclException( interp, "can't upvar from variable to itself" );
}
if ( var.isVarLink() )
{
Var link = (Var)var.value;
if ( link == other )
{
return;
}
link.refCount--;
if ( link.isVarUndefined() )
{
cleanupVar( link, null );
}
}
else if ( !var.isVarUndefined() )
{
throw new TclException( interp, "variable \"" + myName + "\" already exists" );
}
else if ( var.traces != null )
{
throw new TclException( interp, "variable \"" + myName + "\" has traces: can't use for upvar" );
}
}
var.setVarLink();
var.clearVarUndefined();
var.value = other;
other.refCount++;
return;
}
/// <summary> TCL.Tcl_UnsetVar2 -> unsetVar
///
/// Unset a variable, given a two-part name consisting of array
/// name and element within array.
///
/// </summary>
/// <param name="part1">1st part of the variable name.
/// </param>
/// <param name="part2">2nd part of the variable name.
/// </param>
/// <param name="flags">misc flags that control the actions of this method.
///
/// 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.
///
/// </param>
internal static void unsetVar( Interp interp, string part1, string part2, TCL.VarFlag flags )
{
Var dummyVar;
Var var;
Var array;
//ActiveVarTrace active;
TclObject obj;
TCL.CompletionCode result;
// FIXME : what about the null return vs exception thing here?
Var[] lookup_result = lookupVar( interp, part1, part2, flags, "unset", false, false );
if ( lookup_result == null )
{
if ( ( flags & TCL.VarFlag.LEAVE_ERR_MSG ) != 0 )
throw new TclRuntimeError( "unexpected null reference" );
else
return;
}
var = lookup_result[0];
array = lookup_result[1];
result = ( var.isVarUndefined() ? TCL.CompletionCode.ERROR : TCL.CompletionCode.OK );
if ( ( array != null ) && ( array.sidVec != null ) )
{
deleteSearches( array );
}
// 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 = new Var();
//FIXME: Var class really should implement clone to make a bit copy.
dummyVar.value = var.value;
dummyVar.traces = var.traces;
dummyVar.flags = var.flags;
dummyVar.hashKey = var.hashKey;
dummyVar.table = var.table;
dummyVar.refCount = var.refCount;
dummyVar.ns = var.ns;
var.setVarUndefined();
var.setVarScalar();
var.value = null; // dummyVar points to any value object
var.traces = null;
var.sidVec = 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 var's refCount around this: CallTraces
// will use dummyVar so it won't increment var's refCount itself.
// 2. Turn off the TRACE_ACTIVE flag in dummyVar: we want to
// call unset traces even if other traces are pending.
if ( ( dummyVar.traces != null ) || ( ( array != null ) && ( array.traces != null ) ) )
{
var.refCount++;
dummyVar.flags &= ~VarFlags.TRACE_ACTIVE;
callTraces( interp, array, dummyVar, part1, part2, ( flags & ( TCL.VarFlag.GLOBAL_ONLY | TCL.VarFlag.NAMESPACE_ONLY ) ) | TCL.VarFlag.TRACE_UNSETS );
dummyVar.traces = null;
// Active trace stuff is not part of Jacl's interp
var.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).
if ( dummyVar.isVarArray() && !dummyVar.isVarUndefined() )
{
deleteArray( interp, part1, dummyVar, ( flags & ( TCL.VarFlag.GLOBAL_ONLY | TCL.VarFlag.NAMESPACE_ONLY ) ) | TCL.VarFlag.TRACE_UNSETS );
}
if ( dummyVar.isVarScalar() && ( dummyVar.value != null ) )
{
obj = (TclObject)dummyVar.value;
obj.release();
dummyVar.value = null;
}
// If the variable was a namespace variable, decrement its reference count.
if ( ( var.flags & VarFlags.NAMESPACE_VAR ) != 0 )
{
var.flags &= ~VarFlags.NAMESPACE_VAR;
var.refCount--;
}
// 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( var, array );
// It's an error to unset an undefined variable.
if ( result != TCL.CompletionCode.OK )
{
if ( ( flags & TCL.VarFlag.LEAVE_ERR_MSG ) != 0 )
{
throw new TclVarException( interp, part1, part2, "unset", ( ( array == null ) ? noSuchVar : noSuchElement ) );
}
}
}
