/*
* tclListObj.c --
*
* This file contains functions that implement the Tcl list object type.
*
* Copyright (c) 1995-1997 Sun Microsystems, Inc.
* Copyright (c) 1998 by Scriptics Corporation.
* Copyright (c) 2001 by Kevin B. Kenny. All rights reserved.
*
* See the file "license.terms" for information on usage and redistribution of
* this file, and for a DISCLAIMER OF ALL WARRANTIES.
*/
#include "tclInt.h"
/*
* Prototypes for functions defined later in this file:
*/
static List * AttemptNewList(Tcl_Interp *interp, int objc,
Tcl_Obj *const objv[]);
static List * NewListIntRep(int objc, Tcl_Obj *const objv[], int p);
static void DupListInternalRep(Tcl_Obj *srcPtr, Tcl_Obj *copyPtr);
static void FreeListInternalRep(Tcl_Obj *listPtr);
static int SetListFromAny(Tcl_Interp *interp, Tcl_Obj *objPtr);
static void UpdateStringOfList(Tcl_Obj *listPtr);
/*
* The structure below defines the list Tcl object type by means of functions
* that can be invoked by generic object code.
*
* The internal representation of a list object is a two-pointer
* representation. The first pointer designates a List structure that contains
* an array of pointers to the element objects, together with integers that
* represent the current element count and the allocated size of the array.
* The second pointer is normally NULL; during execution of functions in this
* file that operate on nested sublists, it is occasionally used as working
* storage to avoid an auxiliary stack.
*/
const Tcl_ObjType tclListType = {
"list", /* name */
FreeListInternalRep, /* freeIntRepProc */
DupListInternalRep, /* dupIntRepProc */
UpdateStringOfList, /* updateStringProc */
SetListFromAny /* setFromAnyProc */
};
#ifndef TCL_MIN_ELEMENT_GROWTH
#define TCL_MIN_ELEMENT_GROWTH TCL_MIN_GROWTH/sizeof(Tcl_Obj *)
#endif
/*
*----------------------------------------------------------------------
*
* NewListIntRep --
*
* Creates a 'List' structure with space for 'objc' elements. 'objc' must
* be > 0. If 'objv' is not NULL, The list is initialized with first
* 'objc' values in that array. Otherwise the list is initialized to have
* 0 elements, with space to add 'objc' more. Flag value 'p' indicates
* how to behave on failure.
*
* Value
*
* A new 'List' structure with refCount 0. If some failure
* prevents this NULL is returned if 'p' is 0 , and 'Tcl_Panic'
* is called if it is not.
*
* Effect
*
* The refCount of each value in 'objv' is incremented as it is added
* to the list.
*
*----------------------------------------------------------------------
*/
static List *
NewListIntRep(
int objc,
Tcl_Obj *const objv[],
int p)
{
List *listRepPtr;
if (objc <= 0) {
Tcl_Panic("NewListIntRep: expects postive element count");
}
/*
* First check to see if we'd overflow and try to allocate an object
* larger than our memory allocator allows. Note that this is actually a
* fairly small value when you're on a serious 64-bit machine, but that
* requires API changes to fix. See [Bug 219196] for a discussion.
*/
if ((size_t)objc > LIST_MAX) {
if (p) {
Tcl_Panic("max length of a Tcl list (%d elements) exceeded",
LIST_MAX);
}
return NULL;
}
listRepPtr = attemptckalloc(LIST_SIZE(objc));
if (listRepPtr == NULL) {
if (p) {
Tcl_Panic("list creation failed: unable to alloc %u bytes",
LIST_SIZE(objc));
}
return NULL;
}
listRepPtr->canonicalFlag = 0;
listRepPtr->refCount = 0;
listRepPtr->maxElemCount = objc;
if (objv) {
Tcl_Obj **elemPtrs;
int i;
listRepPtr->elemCount = objc;
elemPtrs = &listRepPtr->elements;
for (i = 0; i < objc; i++) {
elemPtrs[i] = objv[i];
Tcl_IncrRefCount(elemPtrs[i]);
}
} else {
listRepPtr->elemCount = 0;
}
return listRepPtr;
}
/*
*----------------------------------------------------------------------
*
* AttemptNewList --
*
* Like NewListIntRep, but additionally sets an error message on failure.
*
*----------------------------------------------------------------------
*/
static List *
AttemptNewList(
Tcl_Interp *interp,
int objc,
Tcl_Obj *const objv[])
{
List *listRepPtr = NewListIntRep(objc, objv, 0);
if (interp != NULL && listRepPtr == NULL) {
if (objc > LIST_MAX) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"max length of a Tcl list (%d elements) exceeded",
LIST_MAX));
} else {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"list creation failed: unable to alloc %u bytes",
LIST_SIZE(objc)));
}
Tcl_SetErrorCode(interp, "TCL", "MEMORY", NULL);
}
return listRepPtr;
}
/*
*----------------------------------------------------------------------
*
* Tcl_NewListObj --
*
* Creates a new list object and adds values to it. When TCL_MEM_DEBUG is
* defined, 'Tcl_DbNewListObj' is called instead.
*
* Value
*
* A new list 'Tcl_Obj' to which is appended values from 'objv', or if
* 'objc' is less than or equal to zero, a list 'Tcl_Obj' having no
* elements. The string representation of the new 'Tcl_Obj' is set to
* NULL. The refCount of the list is 0.
*
* Effect
*
* The refCount of each elements in 'objv' is incremented as it is added
* to the list.
*
*----------------------------------------------------------------------
*/
#ifdef TCL_MEM_DEBUG
#undef Tcl_NewListObj
Tcl_Obj *
Tcl_NewListObj(
int objc, /* Count of objects referenced by objv. */
Tcl_Obj *const objv[]) /* An array of pointers to Tcl objects. */
{
return Tcl_DbNewListObj(objc, objv, "unknown", 0);
}
#else /* if not TCL_MEM_DEBUG */
Tcl_Obj *
Tcl_NewListObj(
int objc, /* Count of objects referenced by objv. */
Tcl_Obj *const objv[]) /* An array of pointers to Tcl objects. */
{
List *listRepPtr;
Tcl_Obj *listPtr;
TclNewObj(listPtr);
if (objc <= 0) {
return listPtr;
}
/*
* Create the internal rep.
*/
listRepPtr = NewListIntRep(objc, objv, 1);
/*
* Now create the object.
*/
TclInvalidateStringRep(listPtr);
ListSetIntRep(listPtr, listRepPtr);
return listPtr;
}
#endif /* if TCL_MEM_DEBUG */
/*
*----------------------------------------------------------------------
*
* Tcl_DbNewListObj --
*
* Like 'Tcl_NewListObj', but it calls Tcl_DbCkalloc directly with the
* file name and line number from its caller. This simplifies debugging
* since the [memory active] command will report the correct file
* name and line number when reporting objects that haven't been freed.
*
* When TCL_MEM_DEBUG is not defined, 'Tcl_NewListObj' is called instead.
*
*----------------------------------------------------------------------
*/
#ifdef TCL_MEM_DEBUG
Tcl_Obj *
Tcl_DbNewListObj(
int objc, /* Count of objects referenced by objv. */
Tcl_Obj *const objv[], /* An array of pointers to Tcl objects. */
const char *file, /* The name of the source file calling this
* function; used for debugging. */
int line) /* Line number in the source file; used for
* debugging. */
{
Tcl_Obj *listPtr;
List *listRepPtr;
TclDbNewObj(listPtr, file, line);
if (objc <= 0) {
return listPtr;
}
/*
* Create the internal rep.
*/
listRepPtr = NewListIntRep(objc, objv, 1);
/*
* Now create the object.
*/
TclInvalidateStringRep(listPtr);
ListSetIntRep(listPtr, listRepPtr);
return listPtr;
}
#else /* if not TCL_MEM_DEBUG */
Tcl_Obj *
Tcl_DbNewListObj(
int objc, /* Count of objects referenced by objv. */
Tcl_Obj *const objv[], /* An array of pointers to Tcl objects. */
const char *file, /* The name of the source file calling this
* function; used for debugging. */
int line) /* Line number in the source file; used for
* debugging. */
{
return Tcl_NewListObj(objc, objv);
}
#endif /* TCL_MEM_DEBUG */
/*
*----------------------------------------------------------------------
*
* Tcl_SetListObj --
*
* Like 'Tcl_NewListObj', but operates on an existing 'Tcl_Obj'instead of
* creating a new one.
*
*----------------------------------------------------------------------
*/
void
Tcl_SetListObj(
Tcl_Obj *objPtr, /* Object whose internal rep to init. */
int objc, /* Count of objects referenced by objv. */
Tcl_Obj *const objv[]) /* An array of pointers to Tcl objects. */
{
List *listRepPtr;
if (Tcl_IsShared(objPtr)) {
Tcl_Panic("%s called with shared object", "Tcl_SetListObj");
}
/*
* Free any old string rep and any internal rep for the old type.
*/
TclFreeIntRep(objPtr);
TclInvalidateStringRep(objPtr);
/*
* Set the object's type to "list" and initialize the internal rep.
* However, if there are no elements to put in the list, just give the
* object an empty string rep and a NULL type.
*/
if (objc > 0) {
listRepPtr = NewListIntRep(objc, objv, 1);
ListSetIntRep(objPtr, listRepPtr);
} else {
objPtr->bytes = tclEmptyStringRep;
objPtr->length = 0;
}
}
/*
*----------------------------------------------------------------------
*
* TclListObjCopy --
*
* Creates a new 'Tcl_Obj' which is a pure copy of a list value. This
* provides for the C level a counterpart of the [lrange $list 0 end]
* command, while using internals details to be as efficient as possible.
*
* Value
*
* The address of the new 'Tcl_Obj' which shares its internal
* representation with 'listPtr', and whose refCount is 0. If 'listPtr'
* is not actually a list, the value is NULL, and an error message is left
* in 'interp' if it is not NULL.
*
* Effect
*
* 'listPtr' is converted to a list if it isn't one already.
*
*----------------------------------------------------------------------
*/
Tcl_Obj *
TclListObjCopy(
Tcl_Interp *interp, /* Used to report errors if not NULL. */
Tcl_Obj *listPtr) /* List object for which an element array is
* to be returned. */
{
Tcl_Obj *copyPtr;
if (listPtr->typePtr != &tclListType) {
if (SetListFromAny(interp, listPtr) != TCL_OK) {
return NULL;
}
}
TclNewObj(copyPtr);
TclInvalidateStringRep(copyPtr);
DupListInternalRep(listPtr, copyPtr);
return copyPtr;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ListObjGetElements --
*
* Retreive the elements in a list 'Tcl_Obj'.
*
* Value
*
* TCL_OK
*
* A count of list elements is stored, 'objcPtr', And a pointer to the
* array of elements in the list is stored in 'objvPtr'.
*
* The elements accessible via 'objvPtr' should be treated as readonly
* and the refCount for each object is _not_ incremented; the caller
* must do that if it holds on to a reference. Furthermore, the
* pointer and length returned by this function may change as soon as
* any function is called on the list object. Be careful about
* retaining the pointer in a local data structure.
*
* TCL_ERROR
*
* 'listPtr' is not a valid list. An error message is left in the
* interpreter's result if 'interp' is not NULL.
*
* Effect
*
* 'listPtr' is converted to a list object if it isn't one already.
*
*----------------------------------------------------------------------
*/
int
Tcl_ListObjGetElements(
Tcl_Interp *interp, /* Used to report errors if not NULL. */
Tcl_Obj *listPtr, /* List object for which an element array is
* to be returned. */
int *objcPtr, /* Where to store the count of objects
* referenced by objv. */
Tcl_Obj ***objvPtr) /* Where to store the pointer to an array of
* pointers to the list's objects. */
{
List *listRepPtr;
if (listPtr->typePtr != &tclListType) {
int result;
if (listPtr->bytes == tclEmptyStringRep) {
*objcPtr = 0;
*objvPtr = NULL;
return TCL_OK;
}
result = SetListFromAny(interp, listPtr);
if (result != TCL_OK) {
return result;
}
}
listRepPtr = ListRepPtr(listPtr);
*objcPtr = listRepPtr->elemCount;
*objvPtr = &listRepPtr->elements;
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ListObjAppendList --
*
* Appends the elements of elemListPtr to those of listPtr.
*
* Value
*
* TCL_OK
*
* Success.
*
* TCL_ERROR
*
* 'listPtr' or 'elemListPtr' are not valid lists. An error
* message is left in the interpreter's result if 'interp' is not NULL.
*
* Effect
*
* The reference count of each element of 'elemListPtr' as it is added to
* 'listPtr'. 'listPtr' and 'elemListPtr' are converted to 'tclListType'
* if they are not already. Appending the new elements may cause the
* array of element pointers in 'listObj' to grow. If any objects are
* appended to 'listPtr'. Any preexisting string representation of
* 'listPtr' is invalidated.
*
*----------------------------------------------------------------------
*/
int
Tcl_ListObjAppendList(
Tcl_Interp *interp, /* Used to report errors if not NULL. */
Tcl_Obj *listPtr, /* List object to append elements to. */
Tcl_Obj *elemListPtr) /* List obj with elements to append. */
{
int objc;
Tcl_Obj **objv;
if (Tcl_IsShared(listPtr)) {
Tcl_Panic("%s called with shared object", "Tcl_ListObjAppendList");
}
/*
* Pull the elements to append from elemListPtr.
*/
if (TCL_OK != TclListObjGetElements(interp, elemListPtr, &objc, &objv)) {
return TCL_ERROR;
}
/*
* Insert the new elements starting after the lists's last element.
* Delete zero existing elements.
*/
return Tcl_ListObjReplace(interp, listPtr, LIST_MAX, 0, objc, objv);
}
/*
*----------------------------------------------------------------------
*
* Tcl_ListObjAppendElement --
*
* Like 'Tcl_ListObjAppendList', but Appends a single value to a list.
*
* Value
*
* TCL_OK
*
* 'objPtr' is appended to the elements of 'listPtr'.
*
* TCL_ERROR
*
* listPtr does not refer to a list object and the object can not be
* converted to one. An error message will be left in the
* interpreter's result if interp is not NULL.
*
* Effect
*
* If 'listPtr' is not already of type 'tclListType', it is converted.
* The 'refCount' of 'objPtr' is incremented as it is added to 'listPtr'.
* Appending the new element may cause the the array of element pointers
* in 'listObj' to grow. Any preexisting string representation of
* 'listPtr' is invalidated.
*
*----------------------------------------------------------------------
*/
int
Tcl_ListObjAppendElement(
Tcl_Interp *interp, /* Used to report errors if not NULL. */
Tcl_Obj *listPtr, /* List object to append objPtr to. */
Tcl_Obj *objPtr) /* Object to append to listPtr's list. */
{
List *listRepPtr, *newPtr = NULL;
int numElems, numRequired, needGrow, isShared, attempt;
if (Tcl_IsShared(listPtr)) {
Tcl_Panic("%s called with shared object", "Tcl_ListObjAppendElement");
}
if (listPtr->typePtr != &tclListType) {
int result;
if (listPtr->bytes == tclEmptyStringRep) {
Tcl_SetListObj(listPtr, 1, &objPtr);
return TCL_OK;
}
result = SetListFromAny(interp, listPtr);
if (result != TCL_OK) {
return result;
}
}
listRepPtr = ListRepPtr(listPtr);
numElems = listRepPtr->elemCount;
numRequired = numElems + 1 ;
needGrow = (numRequired > listRepPtr->maxElemCount);
isShared = (listRepPtr->refCount > 1);
if (numRequired > LIST_MAX) {
if (interp != NULL) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"max length of a Tcl list (%d elements) exceeded",
LIST_MAX));
Tcl_SetErrorCode(interp, "TCL", "MEMORY", NULL);
}
return TCL_ERROR;
}
if (needGrow && !isShared) {
/*
* Need to grow + unshared intrep => try to realloc
*/
attempt = 2 * numRequired;
if (attempt <= LIST_MAX) {
newPtr = attemptckrealloc(listRepPtr, LIST_SIZE(attempt));
}
if (newPtr == NULL) {
attempt = numRequired + 1 + TCL_MIN_ELEMENT_GROWTH;
if (attempt > LIST_MAX) {
attempt = LIST_MAX;
}
newPtr = attemptckrealloc(listRepPtr, LIST_SIZE(attempt));
}
if (newPtr == NULL) {
attempt = numRequired;
newPtr = attemptckrealloc(listRepPtr, LIST_SIZE(attempt));
}
if (newPtr) {
listRepPtr = newPtr;
listRepPtr->maxElemCount = attempt;
needGrow = 0;
}
}
if (isShared || needGrow) {
Tcl_Obj **dst, **src = &listRepPtr->elements;
/*
* Either we have a shared intrep and we must copy to write, or we
* need to grow and realloc attempts failed. Attempt intrep copy.
*/
attempt = 2 * numRequired;
newPtr = AttemptNewList(NULL, attempt, NULL);
if (newPtr == NULL) {
attempt = numRequired + 1 + TCL_MIN_ELEMENT_GROWTH;
if (attempt > LIST_MAX) {
attempt = LIST_MAX;
}
newPtr = AttemptNewList(NULL, attempt, NULL);
}
if (newPtr == NULL) {
attempt = numRequired;
newPtr = AttemptNewList(interp, attempt, NULL);
}
if (newPtr == NULL) {
/*
* All growth attempts failed; throw the error.
*/
return TCL_ERROR;
}
dst = &newPtr->elements;
newPtr->refCount++;
newPtr->canonicalFlag = listRepPtr->canonicalFlag;
newPtr->elemCount = listRepPtr->elemCount;
if (isShared) {
/*
* The original intrep must remain undisturbed. Copy into the new
* one and bump refcounts
*/
while (numElems--) {
*dst = *src++;
Tcl_IncrRefCount(*dst++);
}
listRepPtr->refCount--;
} else {
/*
* Old intrep to be freed, re-use refCounts.
*/
memcpy(dst, src, numElems * sizeof(Tcl_Obj *));
ckfree(listRepPtr);
}
listRepPtr = newPtr;
}
listPtr->internalRep.twoPtrValue.ptr1 = listRepPtr;
/*
* Add objPtr to the end of listPtr's array of element pointers. Increment
* the ref count for the (now shared) objPtr.
*/
*(&listRepPtr->elements + listRepPtr->elemCount) = objPtr;
Tcl_IncrRefCount(objPtr);
listRepPtr->elemCount++;
/*
* Invalidate any old string representation since the list's internal
* representation has changed.
*/
TclInvalidateStringRep(listPtr);
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ListObjIndex --
*
* Retrieve a pointer to the element of 'listPtr' at 'index'. The index
* of the first element is 0.
*
* Value
*
* TCL_OK
*
* A pointer to the element at 'index' is stored in 'objPtrPtr'. If
* 'index' is out of range, NULL is stored in 'objPtrPtr'. This
* object should be treated as readonly and its 'refCount' is _not_
* incremented. The caller must do that if it holds on to the
* reference.
*
* TCL_ERROR
*
* 'listPtr' is not a valid list. An an error message is left in the
* interpreter's result if 'interp' is not NULL.
*
* Effect
*
* If 'listPtr' is not already of type 'tclListType', it is converted.
*
*----------------------------------------------------------------------
*/
int
Tcl_ListObjIndex(
Tcl_Interp *interp, /* Used to report errors if not NULL. */
Tcl_Obj *listPtr, /* List object to index into. */
int index, /* Index of element to return. */
Tcl_Obj **objPtrPtr) /* The resulting Tcl_Obj* is stored here. */
{
List *listRepPtr;
if (listPtr->typePtr != &tclListType) {
int result;
if (listPtr->bytes == tclEmptyStringRep) {
*objPtrPtr = NULL;
return TCL_OK;
}
result = SetListFromAny(interp, listPtr);
if (result != TCL_OK) {
return result;
}
}
listRepPtr = ListRepPtr(listPtr);
if ((index < 0) || (index >= listRepPtr->elemCount)) {
*objPtrPtr = NULL;
} else {
*objPtrPtr = (&listRepPtr->elements)[index];
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ListObjLength --
*
* Retrieve the number of elements in a list.
*
* Value
*
* TCL_OK
*
* A count of list elements is stored at the address provided by
* 'intPtr'. If 'listPtr' is not already of type 'tclListPtr', it is
* converted.
*
* TCL_ERROR
*
* 'listPtr' is not a valid list. An error message will be left in
* the interpreter's result if 'interp' is not NULL.
*
*----------------------------------------------------------------------
*/
int
Tcl_ListObjLength(
Tcl_Interp *interp, /* Used to report errors if not NULL. */
Tcl_Obj *listPtr, /* List object whose #elements to return. */
int *intPtr) /* The resulting int is stored here. */
{
List *listRepPtr;
if (listPtr->typePtr != &tclListType) {
int result;
if (listPtr->bytes == tclEmptyStringRep) {
*intPtr = 0;
return TCL_OK;
}
result = SetListFromAny(interp, listPtr);
if (result != TCL_OK) {
return result;
}
}
listRepPtr = ListRepPtr(listPtr);
*intPtr = listRepPtr->elemCount;
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ListObjReplace --
*
* Replace values in a list.
*
* If 'first' is zero or negative, it refers to the first element. If
* 'first' outside the range of elements in the list, no elements are
* deleted.
*
* If 'count' is zero or negative no elements are deleted, and any new
* elements are inserted at the beginning of the list.
*
* Value
*
* TCL_OK
*
* The first 'objc' values of 'objv' replaced 'count' elements in 'listPtr'
* starting at 'first'. If 'objc' 0, no new elements are added.
*
* TCL_ERROR
*
* 'listPtr' is not a valid list. An error message is left in the
* interpreter's result if 'interp' is not NULL.
*
* Effect
*
* If 'listPtr' is not of type 'tclListType', it is converted if possible.
*
* The 'refCount' of each element appended to the list is incremented.
* Similarly, the 'refCount' for each replaced element is decremented.
*
* If 'listPtr' is modified, any previous string representation is
* invalidated.
*
*----------------------------------------------------------------------
*/
int
Tcl_ListObjReplace(
Tcl_Interp *interp, /* Used for error reporting if not NULL. */
Tcl_Obj *listPtr, /* List object whose elements to replace. */
int first, /* Index of first element to replace. */
int count, /* Number of elements to replace. */
int objc, /* Number of objects to insert. */
Tcl_Obj *const objv[]) /* An array of objc pointers to Tcl objects to
* insert. */
{
List *listRepPtr;
Tcl_Obj **elemPtrs;
int needGrow, numElems, numRequired, numAfterLast, start, i, j, isShared;
if (Tcl_IsShared(listPtr)) {
Tcl_Panic("%s called with shared object", "Tcl_ListObjReplace");
}
if (listPtr->typePtr != &tclListType) {
if (listPtr->bytes == tclEmptyStringRep) {
if (!objc) {
return TCL_OK;
}
Tcl_SetListObj(listPtr, objc, NULL);
} else {
int result = SetListFromAny(interp, listPtr);
if (result != TCL_OK) {
return result;
}
}
}
/*
* Note that when count == 0 and objc == 0, this routine is logically a
* no-op, removing and adding no elements to the list. However, by flowing
* through this routine anyway, we get the important side effect that the
* resulting listPtr is a list in canoncial form. This is important.
* Resist any temptation to optimize this case.
*/
listRepPtr = ListRepPtr(listPtr);
elemPtrs = &listRepPtr->elements;
numElems = listRepPtr->elemCount;
if (first < 0) {
first = 0;
}
if (first >= numElems) {
first = numElems; /* So we'll insert after last element. */
}
if (count < 0) {
count = 0;
} else if (first > INT_MAX - count /* Handle integer overflow */
|| numElems < first+count) {
count = numElems - first;
}
if (objc > LIST_MAX - (numElems - count)) {
if (interp != NULL) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"max length of a Tcl list (%d elements) exceeded",
LIST_MAX));
}
return TCL_ERROR;
}
isShared = (listRepPtr->refCount > 1);
numRequired = numElems - count + objc; /* Known <= LIST_MAX */
needGrow = numRequired > listRepPtr->maxElemCount;
for (i = 0; i < objc; i++) {
Tcl_IncrRefCount(objv[i]);
}
if (needGrow && !isShared) {
/* Try to use realloc */
List *newPtr = NULL;
int attempt = 2 * numRequired;
if (attempt <= LIST_MAX) {
newPtr = attemptckrealloc(listRepPtr, LIST_SIZE(attempt));
}
if (newPtr == NULL) {
attempt = numRequired + 1 + TCL_MIN_ELEMENT_GROWTH;
if (attempt > LIST_MAX) {
attempt = LIST_MAX;
}
newPtr = attemptckrealloc(listRepPtr, LIST_SIZE(attempt));
}
if (newPtr == NULL) {
attempt = numRequired;
newPtr = attemptckrealloc(listRepPtr, LIST_SIZE(attempt));
}
if (newPtr) {
listRepPtr = newPtr;
listPtr->internalRep.twoPtrValue.ptr1 = listRepPtr;
elemPtrs = &listRepPtr->elements;
listRepPtr->maxElemCount = attempt;
needGrow = numRequired > listRepPtr->maxElemCount;
}
}
if (!needGrow && !isShared) {
int shift;
/*
* Can use the current List struct. First "delete" count elements
* starting at first.
*/
for (j = first; j < first + count; j++) {
Tcl_Obj *victimPtr = elemPtrs[j];
TclDecrRefCount(victimPtr);
}
/*
* Shift the elements after the last one removed to their new
* locations.
*/
start = first + count;
numAfterLast = numElems - start;
shift = objc - count; /* numNewElems - numDeleted */
if ((numAfterLast > 0) && (shift != 0)) {
Tcl_Obj **src = elemPtrs + start;
memmove(src+shift, src, numAfterLast * sizeof(Tcl_Obj*));
}
} else {
/*
* Cannot use the current List struct; it is shared, too small, or
* both. Allocate a new struct and insert elements into it.
*/
List *oldListRepPtr = listRepPtr;
Tcl_Obj **oldPtrs = elemPtrs;
int newMax;
if (needGrow){
newMax = 2 * numRequired;
} else {
newMax = listRepPtr->maxElemCount;
}
listRepPtr = AttemptNewList(NULL, newMax, NULL);
if (listRepPtr == NULL) {
unsigned int limit = LIST_MAX - numRequired;
unsigned int extra = numRequired - numElems
+ TCL_MIN_ELEMENT_GROWTH;
int growth = (int) ((extra > limit) ? limit : extra);
listRepPtr = AttemptNewList(NULL, numRequired + growth, NULL);
if (listRepPtr == NULL) {
listRepPtr = AttemptNewList(interp, numRequired, NULL);
if (listRepPtr == NULL) {
for (i = 0; i < objc; i++) {
/* See bug 3598580 */
#if TCL_MAJOR_VERSION > 8
Tcl_DecrRefCount(objv[i]);
#else
objv[i]->refCount--;
#endif
}
return TCL_ERROR;
}
}
}
listPtr->internalRep.twoPtrValue.ptr1 = listRepPtr;
listRepPtr->refCount++;
elemPtrs = &listRepPtr->elements;
if (isShared) {
/*
* The old struct will remain in place; need new refCounts for the
* new List struct references. Copy over only the surviving
* elements.
*/
for (i=0; i < first; i++) {
elemPtrs[i] = oldPtrs[i];
Tcl_IncrRefCount(elemPtrs[i]);
}
for (i = first + count, j = first + objc;
j < numRequired; i++, j++) {
elemPtrs[j] = oldPtrs[i];
Tcl_IncrRefCount(elemPtrs[j]);
}
oldListRepPtr->refCount--;
} else {
/*
* The old struct will be removed; use its inherited refCounts.
*/
if (first > 0) {
memcpy(elemPtrs, oldPtrs, first * sizeof(Tcl_Obj *));
}
/*
* "Delete" count elements starting at first.
*/
for (j = first; j < first + count; j++) {
Tcl_Obj *victimPtr = oldPtrs[j];
TclDecrRefCount(victimPtr);
}
/*
* Copy the elements after the last one removed, shifted to their
* new locations.
*/
start = first + count;
numAfterLast = numElems - start;
if (numAfterLast > 0) {
memcpy(elemPtrs + first + objc, oldPtrs + start,
(size_t) numAfterLast * sizeof(Tcl_Obj *));
}
ckfree(oldListRepPtr);
}
}
/*
* Insert the new elements into elemPtrs before "first".
*/
for (i=0,j=first ; i<objc ; i++,j++) {
elemPtrs[j] = objv[i];
}
/*
* Update the count of elements.
*/
listRepPtr->elemCount = numRequired;
/*
* Invalidate and free any old string representation since it no longer
* reflects the list's internal representation.
*/
TclInvalidateStringRep(listPtr);
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* TclLindexList --
*
* Implements the 'lindex' command when objc==3.
*
* Implemented entirely as a wrapper around 'TclLindexFlat'. Reconfigures
* the argument format into required form while taking care to manage
* shimmering so as to tend to keep the most useful intreps
* and/or avoid the most expensive conversions.
*
* Value
*
* A pointer to the specified element, with its 'refCount' incremented, or
* NULL if an error occurred.
*
* Notes
*
*----------------------------------------------------------------------
*/
Tcl_Obj *
TclLindexList(
Tcl_Interp *interp, /* Tcl interpreter. */
Tcl_Obj *listPtr, /* List being unpacked. */
Tcl_Obj *argPtr) /* Index or index list. */
{
int index; /* Index into the list. */
Tcl_Obj *indexListCopy;
/*
* Determine whether argPtr designates a list or a single index. We have
* to be careful about the order of the checks to avoid repeated
* shimmering; see TIP#22 and TIP#33 for the details.
*/
if (argPtr->typePtr != &tclListType
&& TclGetIntForIndexM(NULL , argPtr, 0, &index) == TCL_OK) {
/*
* argPtr designates a single index.
*/
return TclLindexFlat(interp, listPtr, 1, &argPtr);
}
/*
* Here we make a private copy of the index list argument to avoid any
* shimmering issues that might invalidate the indices array below while
* we are still using it. This is probably unnecessary. It does not appear
* that any damaging shimmering is possible, and no test has been devised
* to show any error when this private copy is not made. But it's cheap,
* and it offers some future-proofing insurance in case the TclLindexFlat
* implementation changes in some unexpected way, or some new form of
* trace or callback permits things to happen that the current
* implementation does not.
*/
indexListCopy = TclListObjCopy(NULL, argPtr);
if (indexListCopy == NULL) {
/*
* argPtr designates something that is neither an index nor a
* well-formed list. Report the error via TclLindexFlat.
*/
return TclLindexFlat(interp, listPtr, 1, &argPtr);
}
{
int indexCount = -1; /* Size of the array of list indices. */
Tcl_Obj **indices = NULL; /* Array of list indices. */
TclListObjGetElements(NULL, indexListCopy, &indexCount, &indices);
listPtr = TclLindexFlat(interp, listPtr, indexCount, indices);
}
Tcl_DecrRefCount(indexListCopy);
return listPtr;
}
/*
*----------------------------------------------------------------------
*
* TclLindexFlat --
*
* The core of the 'lindex' command, with all index
* arguments presented as a flat list.
*
* Value
*
* A pointer to the object extracted, with its 'refCount' incremented, or
* NULL if an error occurred. Thus, the calling code will usually do
* something like:
*
* Tcl_SetObjResult(interp, result);
* Tcl_DecrRefCount(result);
*
*
*----------------------------------------------------------------------
*/
Tcl_Obj *
TclLindexFlat(
Tcl_Interp *interp, /* Tcl interpreter. */
Tcl_Obj *listPtr, /* Tcl object representing the list. */
int indexCount, /* Count of indices. */
Tcl_Obj *const indexArray[])/* Array of pointers to Tcl objects that
* represent the indices in the list. */
{
int i;
Tcl_IncrRefCount(listPtr);
for (i=0 ; i<indexCount && listPtr ; i++) {
int index, listLen = 0;
Tcl_Obj **elemPtrs = NULL, *sublistCopy;
/*
* Here we make a private copy of the current sublist, so we avoid any
* shimmering issues that might invalidate the elemPtr array below
* while we are still using it. See test lindex-8.4.
*/
sublistCopy = TclListObjCopy(interp, listPtr);
Tcl_DecrRefCount(listPtr);
listPtr = NULL;
if (sublistCopy == NULL) {
/*
* The sublist is not a list at all => error.
*/
break;
}
TclListObjGetElements(NULL, sublistCopy, &listLen, &elemPtrs);
if (TclGetIntForIndexM(interp, indexArray[i], /*endValue*/ listLen-1,
&index) == TCL_OK) {
if (index<0 || index>=listLen) {
/*
* Index is out of range. Break out of loop with empty result.
* First check remaining indices for validity
*/
while (++i < indexCount) {
if (TclGetIntForIndexM(interp, indexArray[i], -1, &index)
!= TCL_OK) {
Tcl_DecrRefCount(sublistCopy);
return NULL;
}
}
TclNewObj(listPtr);
} else {
/*
* Extract the pointer to the appropriate element.
*/
listPtr = elemPtrs[index];
}
Tcl_IncrRefCount(listPtr);
}
Tcl_DecrRefCount(sublistCopy);
}
return listPtr;
}
/*
*----------------------------------------------------------------------
*
* TclLsetList --
*
* The core of [lset] when objc == 4. Objv[2] may be either a
* scalar index or a list of indices.
*
* Implemented entirely as a wrapper around 'TclLindexFlat', as described
* for 'TclLindexList'.
*
* Value
*
* The new list, with the 'refCount' of 'valuPtr' incremented, or NULL if
* there was an error.
*
*----------------------------------------------------------------------
*/
Tcl_Obj *
TclLsetList(
Tcl_Interp *interp, /* Tcl interpreter. */
Tcl_Obj *listPtr, /* Pointer to the list being modified. */
Tcl_Obj *indexArgPtr, /* Index or index-list arg to 'lset'. */
Tcl_Obj *valuePtr) /* Value arg to 'lset'. */
{
int indexCount = 0; /* Number of indices in the index list. */
Tcl_Obj **indices = NULL; /* Vector of indices in the index list. */
Tcl_Obj *retValuePtr; /* Pointer to the list to be returned. */
int index; /* Current index in the list - discarded. */
Tcl_Obj *indexListCopy;
/*
* Determine whether the index arg designates a list or a single index.
* We have to be careful about the order of the checks to avoid repeated
* shimmering; see TIP #22 and #23 for details.
*/
if (indexArgPtr->typePtr != &tclListType
&& TclGetIntForIndexM(NULL, indexArgPtr, 0, &index) == TCL_OK) {
/*
* indexArgPtr designates a single index.
*/
return TclLsetFlat(interp, listPtr, 1, &indexArgPtr, valuePtr);
}
indexListCopy = TclListObjCopy(NULL, indexArgPtr);
if (indexListCopy == NULL) {
/*
* indexArgPtr designates something that is neither an index nor a
* well formed list. Report the error via TclLsetFlat.
*/
return TclLsetFlat(interp, listPtr, 1, &indexArgPtr, valuePtr);
}
TclListObjGetElements(NULL, indexArgPtr, &indexCount, &indices);
/*
* Let TclLsetFlat handle the actual lset'ting.
*/
retValuePtr = TclLsetFlat(interp, listPtr, indexCount, indices, valuePtr);
Tcl_DecrRefCount(indexListCopy);
return retValuePtr;
}
/*
*----------------------------------------------------------------------
*
* TclLsetFlat --
*
* Core engine of the 'lset' command.
*
* Value
*
* The resulting list
*
* The 'refCount' of 'valuePtr' is incremented. If 'listPtr' was not
* duplicated, its 'refCount' is incremented. The reference count of
* an unduplicated object is therefore 2 (one for the returned pointer
* and one for the variable that holds it). The reference count of a
* duplicate object is 1, reflecting that result is the only active
* reference. The caller is expected to store the result in the
* variable and decrement its reference count. (INST_STORE_* does
* exactly this.)
*
* NULL
*
* An error occurred. If 'listPtr' was duplicated, the reference
* count on the duplicate is decremented so that it is 0, causing any
* memory allocated by this function to be freed.
*
*
* Effect
*
* On entry, the reference count of 'listPtr' does not reflect any
* references held on the stack. The first action of this function is to
* determine whether 'listPtr' is shared and to create a duplicate
* unshared copy if it is. The reference count of the duplicate is
* incremented. At this point, the reference count is 1 in either case so
* that the object is considered unshared.
*
* The unshared list is altered directly to produce the result.
* 'TclLsetFlat' maintains a linked list of 'Tcl_Obj' values whose string
* representations must be spoilt by threading via 'ptr2' of the
* two-pointer internal representation. On entry to 'TclLsetFlat', the
* values of 'ptr2' are immaterial; on exit, the 'ptr2' field of any
* Tcl_Obj that has been modified is set to NULL.
*
*----------------------------------------------------------------------
*/
Tcl_Obj *
TclLsetFlat(
Tcl_Interp *interp, /* Tcl interpreter. */
Tcl_Obj *listPtr, /* Pointer to the list being modified. */
int indexCount, /* Number of index args. */
Tcl_Obj *const indexArray[],
/* Index args. */
Tcl_Obj *valuePtr) /* Value arg to 'lset'. */
{
int index, result, len;
Tcl_Obj *subListPtr, *retValuePtr, *chainPtr;
/*
* If there are no indices, simply return the new value. (Without
* indices, [lset] is a synonym for [set].
*/
if (indexCount == 0) {
Tcl_IncrRefCount(valuePtr);
return valuePtr;
}
/*
* If the list is shared, make a copy we can modify (copy-on-write). We
* use Tcl_DuplicateObj() instead of TclListObjCopy() for a few reasons:
* 1) we have not yet confirmed listPtr is actually a list; 2) We make a
* verbatim copy of any existing string rep, and when we combine that with
* the delayed invalidation of string reps of modified Tcl_Obj's
* implemented below, the outcome is that any error condition that causes
* this routine to return NULL, will leave the string rep of listPtr and
* all elements to be unchanged.
*/
subListPtr = Tcl_IsShared(listPtr) ? Tcl_DuplicateObj(listPtr) : listPtr;
/*
* Anchor the linked list of Tcl_Obj's whose string reps must be
* invalidated if the operation succeeds.
*/
retValuePtr = subListPtr;
chainPtr = NULL;
result = TCL_OK;
/*
* Loop through all the index arguments, and for each one dive into the
* appropriate sublist.
*/
do {
int elemCount;
Tcl_Obj *parentList, **elemPtrs;
/*
* Check for the possible error conditions...
*/
if (TclListObjGetElements(interp, subListPtr, &elemCount, &elemPtrs)
!= TCL_OK) {
/* ...the sublist we're indexing into isn't a list at all. */
result = TCL_ERROR;
break;
}
/*
* WARNING: the macro TclGetIntForIndexM is not safe for
* post-increments, avoid '*indexArray++' here.
*/
if (TclGetIntForIndexM(interp, *indexArray, elemCount - 1, &index)
!= TCL_OK) {
/* ...the index we're trying to use isn't an index at all. */
result = TCL_ERROR;
indexArray++;
break;
}
indexArray++;
if (index < 0 || index > elemCount) {
/* ...the index points outside the sublist. */
if (interp != NULL) {
Tcl_SetObjResult(interp,
Tcl_NewStringObj("list index out of range", -1));
Tcl_SetErrorCode(interp, "TCL", "OPERATION", "LSET",
"BADINDEX", NULL);
}
result = TCL_ERROR;
break;
}
/*
* No error conditions. As long as we're not yet on the last index,
* determine the next sublist for the next pass through the loop, and
* take steps to make sure it is an unshared copy, as we intend to
* modify it.
*/
if (--indexCount) {
parentList = subListPtr;
if (index == elemCount) {
TclNewObj(subListPtr);
} else {
subListPtr = elemPtrs[index];
}
if (Tcl_IsShared(subListPtr)) {
subListPtr = Tcl_DuplicateObj(subListPtr);
}
/*
* Replace the original elemPtr[index] in parentList with a copy
* we know to be unshared. This call will also deal with the
* situation where parentList shares its intrep with other
* Tcl_Obj's. Dealing with the shared intrep case can cause
* subListPtr to become shared again, so detect that case and make
* and store another copy.
*/
if (index == elemCount) {
Tcl_ListObjAppendElement(NULL, parentList, subListPtr);
} else {
TclListObjSetElement(NULL, parentList, index, subListPtr);
}
if (Tcl_IsShared(subListPtr)) {
subListPtr = Tcl_DuplicateObj(subListPtr);
TclListObjSetElement(NULL, parentList, index, subListPtr);
}
/*
* The TclListObjSetElement() calls do not spoil the string rep of
* parentList, and that's fine for now, since all we've done so
* far is replace a list element with an unshared copy. The list
* value remains the same, so the string rep. is still valid, and
* unchanged, which is good because if this whole routine returns
* NULL, we'd like to leave no change to the value of the lset
* variable. Later on, when we set valuePtr in its proper place,
* then all containing lists will have their values changed, and
* will need their string reps spoiled. We maintain a list of all
* those Tcl_Obj's (via a little intrep surgery) so we can spoil
* them at that time.
*/
parentList->internalRep.twoPtrValue.ptr2 = chainPtr;
chainPtr = parentList;
}
} while (indexCount > 0);
/*
* Either we've detected and error condition, and exited the loop with
* result == TCL_ERROR, or we've successfully reached the last index, and
* we're ready to store valuePtr. In either case, we need to clean up our
* string spoiling list of Tcl_Obj's.
*/
while (chainPtr) {
Tcl_Obj *objPtr = chainPtr;
if (result == TCL_OK) {
/*
* We're going to store valuePtr, so spoil string reps of all
* containing lists.
*/
TclInvalidateStringRep(objPtr);
}
/*
* Clear away our intrep surgery mess.
*/
chainPtr = objPtr->internalRep.twoPtrValue.ptr2;
objPtr->internalRep.twoPtrValue.ptr2 = NULL;
}
if (result != TCL_OK) {
/*
* Error return; message is already in interp. Clean up any excess
* memory.
*/
if (retValuePtr != listPtr) {
Tcl_DecrRefCount(retValuePtr);
}
return NULL;
}
/*
* Store valuePtr in proper sublist and return. The -1 is to avoid a
* compiler warning (not a problem because we checked that we have a
* proper list - or something convertible to one - above).
*/
len = -1;
TclListObjLength(NULL, subListPtr, &len);
if (index == len) {
Tcl_ListObjAppendElement(NULL, subListPtr, valuePtr);
} else {
TclListObjSetElement(NULL, subListPtr, index, valuePtr);
}
TclInvalidateStringRep(subListPtr);
Tcl_IncrRefCount(retValuePtr);
return retValuePtr;
}
/*
*----------------------------------------------------------------------
*
* TclListObjSetElement --
*
* Set a single element of a list to a specified value.
*
* It is the caller's responsibility to invalidate the string
* representation of the 'listPtr'.
*
* Value
*
* TCL_OK
*
* Success.
*
* TCL_ERROR
*
* 'listPtr' does not refer to a list object and cannot be converted
* to one. An error message will be left in the interpreter result if
* interp is not NULL.
*
* TCL_ERROR
*
* An index designates an element outside the range [0..listLength-1],
* where 'listLength' is the count of elements in the list object
* designated by 'listPtr'. An error message is left in the
* interpreter result.
*
* Effect
*
* If 'listPtr' designates a shared object, 'Tcl_Panic' is called. If
* 'listPtr' is not already of type 'tclListType', it is converted and the
* internal representation is unshared. The 'refCount' of the element at
* 'index' is decremented and replaced in the list with the 'valuePtr',
* whose 'refCount' in turn is incremented.
*
*
*----------------------------------------------------------------------
*/
int
TclListObjSetElement(
Tcl_Interp *interp, /* Tcl interpreter; used for error reporting
* if not NULL. */
Tcl_Obj *listPtr, /* List object in which element should be
* stored. */
int index, /* Index of element to store. */
Tcl_Obj *valuePtr) /* Tcl object to store in the designated list
* element. */
{
List *listRepPtr; /* Internal representation of the list being
* modified. */
Tcl_Obj **elemPtrs; /* Pointers to elements of the list. */
int elemCount; /* Number of elements in the list. */
/*
* Ensure that the listPtr parameter designates an unshared list.
*/
if (Tcl_IsShared(listPtr)) {
Tcl_Panic("%s called with shared object", "TclListObjSetElement");
}
if (listPtr->typePtr != &tclListType) {
int result;
if (listPtr->bytes == tclEmptyStringRep) {
if (interp != NULL) {
Tcl_SetObjResult(interp,
Tcl_NewStringObj("list index out of range", -1));
Tcl_SetErrorCode(interp, "TCL", "OPERATION", "LSET",
"BADINDEX", NULL);
}
return TCL_ERROR;
}
result = SetListFromAny(interp, listPtr);
if (result != TCL_OK) {
return result;
}
}
listRepPtr = ListRepPtr(listPtr);
elemCount = listRepPtr->elemCount;
/*
* Ensure that the index is in bounds.
*/
if (index<0 || index>=elemCount) {
if (interp != NULL) {
Tcl_SetObjResult(interp,
Tcl_NewStringObj("list index out of range", -1));
Tcl_SetErrorCode(interp, "TCL", "OPERATION", "LSET", "BADINDEX",
NULL);
}
return TCL_ERROR;
}
/*
* If the internal rep is shared, replace it with an unshared copy.
*/
if (listRepPtr->refCount > 1) {
Tcl_Obj **dst, **src = &listRepPtr->elements;
List *newPtr = AttemptNewList(NULL, listRepPtr->maxElemCount, NULL);
if (newPtr == NULL) {
newPtr = AttemptNewList(interp, elemCount, NULL);
if (newPtr == NULL) {
return TCL_ERROR;
}
}
newPtr->refCount++;
newPtr->elemCount = elemCount;
newPtr->canonicalFlag = listRepPtr->canonicalFlag;
dst = &newPtr->elements;
while (elemCount--) {
*dst = *src++;
Tcl_IncrRefCount(*dst++);
}
listRepPtr->refCount--;
listPtr->internalRep.twoPtrValue.ptr1 = listRepPtr = newPtr;
}
elemPtrs = &listRepPtr->elements;
/*
* Add a reference to the new list element.
*/
Tcl_IncrRefCount(valuePtr);
/*
* Remove a reference from the old list element.
*/
Tcl_DecrRefCount(elemPtrs[index]);
/*
* Stash the new object in the list.
*/
elemPtrs[index] = valuePtr;
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* FreeListInternalRep --
*
* Deallocate the storage associated with the internal representation of a
* a list object.
*
* Effect
*
* The storage for the internal 'List' pointer of 'listPtr' is freed, the
* 'internalRep.twoPtrValue.ptr1' of 'listPtr' is set to NULL, and the 'refCount'
* of each element of the list is decremented.
*
*----------------------------------------------------------------------
*/
static void
FreeListInternalRep(
Tcl_Obj *listPtr) /* List object with internal rep to free. */
{
List *listRepPtr = ListRepPtr(listPtr);
if (listRepPtr->refCount-- <= 1) {
Tcl_Obj **elemPtrs = &listRepPtr->elements;
int i, numElems = listRepPtr->elemCount;
for (i = 0; i < numElems; i++) {
Tcl_DecrRefCount(elemPtrs[i]);
}
ckfree(listRepPtr);
}
listPtr->typePtr = NULL;
}
/*
*----------------------------------------------------------------------
*
* DupListInternalRep --
*
* Initialize the internal representation of a list 'Tcl_Obj' to share the
* internal representation of an existing list object.
*
* Effect
*
* The 'refCount' of the List internal rep is incremented.
*
*----------------------------------------------------------------------
*/
static void
DupListInternalRep(
Tcl_Obj *srcPtr, /* Object with internal rep to copy. */
Tcl_Obj *copyPtr) /* Object with internal rep to set. */
{
List *listRepPtr = ListRepPtr(srcPtr);
ListSetIntRep(copyPtr, listRepPtr);
}
/*
*----------------------------------------------------------------------
*
* SetListFromAny --
*
* Convert any object to a list.
*
* Value
*
* TCL_OK
*
* Success. The internal representation of 'objPtr' is set, and the type
* of 'objPtr' is 'tclListType'.
*
* TCL_ERROR
*
* An error occured during conversion. An error message is left in the
* interpreter's result if 'interp' is not NULL.
*
*
*----------------------------------------------------------------------
*/
static int
SetListFromAny(
Tcl_Interp *interp, /* Used for error reporting if not NULL. */
Tcl_Obj *objPtr) /* The object to convert. */
{
List *listRepPtr;
Tcl_Obj **elemPtrs;
/*
* Dictionaries are a special case; they have a string representation such
* that *all* valid dictionaries are valid lists. Hence we can convert
* more directly. Only do this when there's no existing string rep; if
* there is, it is the string rep that's authoritative (because it could
* describe duplicate keys).
*/
if (objPtr->typePtr == &tclDictType && !objPtr->bytes) {
Tcl_Obj *keyPtr, *valuePtr;
Tcl_DictSearch search;
int done, size;
/*
* Create the new list representation. Note that we do not need to do
* anything with the string representation as the transformation (and
* the reverse back to a dictionary) are both order-preserving. Also
* note that since we know we've got a valid dictionary (by
* representation) we also know that fetching the size of the
* dictionary or iterating over it will not fail.
*/
Tcl_DictObjSize(NULL, objPtr, &size);
listRepPtr = AttemptNewList(interp, size > 0 ? 2*size : 1, NULL);
if (!listRepPtr) {
return TCL_ERROR;
}
listRepPtr->elemCount = 2 * size;
/*
* Populate the list representation.
*/
elemPtrs = &listRepPtr->elements;
Tcl_DictObjFirst(NULL, objPtr, &search, &keyPtr, &valuePtr, &done);
while (!done) {
*elemPtrs++ = keyPtr;
*elemPtrs++ = valuePtr;
Tcl_IncrRefCount(keyPtr);
Tcl_IncrRefCount(valuePtr);
Tcl_DictObjNext(&search, &keyPtr, &valuePtr, &done);
}
} else {
int estCount, length;
const char *limit, *nextElem = TclGetStringFromObj(objPtr, &length);
/*
* Allocate enough space to hold a (Tcl_Obj *) for each
* (possible) list element.
*/
estCount = TclMaxListLength(nextElem, length, &limit);
estCount += (estCount == 0); /* Smallest list struct holds 1
* element. */
listRepPtr = AttemptNewList(interp, estCount, NULL);
if (listRepPtr == NULL) {
return TCL_ERROR;
}
elemPtrs = &listRepPtr->elements;
/*
* Each iteration, parse and store a list element.
*/
while (nextElem < limit) {
const char *elemStart;
int elemSize, literal;
if (TCL_OK != TclFindElement(interp, nextElem, limit - nextElem,
&elemStart, &nextElem, &elemSize, &literal)) {
while (--elemPtrs >= &listRepPtr->elements) {
Tcl_DecrRefCount(*elemPtrs);
}
ckfree((char *) listRepPtr);
return TCL_ERROR;
}
if (elemStart == limit) {
break;
}
/* TODO: replace panic with error on alloc failure? */
if (literal) {
TclNewStringObj(*elemPtrs, elemStart, elemSize);
} else {
TclNewObj(*elemPtrs);
(*elemPtrs)->bytes = ckalloc((unsigned) elemSize + 1);
(*elemPtrs)->length = TclCopyAndCollapse(elemSize, elemStart,
(*elemPtrs)->bytes);
}
Tcl_IncrRefCount(*elemPtrs++);/* Since list now holds ref to it. */
}
listRepPtr->elemCount = elemPtrs - &listRepPtr->elements;
}
/*
* Free the old internalRep before setting the new one. We do this as late
* as possible to allow the conversion code, in particular
* Tcl_GetStringFromObj, to use that old internalRep.
*/
TclFreeIntRep(objPtr);
ListSetIntRep(objPtr, listRepPtr);
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* UpdateStringOfList --
*
* Update the string representation for a list object.
*
* Any previously-exising string representation is not invalidated, so
* storage is lost if this has not been taken care of.
*
* Effect
*
* The string representation of 'listPtr' is set to the resulting string.
* This string will be empty if the list has no elements. It is assumed
* that the list internal representation is not NULL.
*
*----------------------------------------------------------------------
*/
static void
UpdateStringOfList(
Tcl_Obj *listPtr) /* List object with string rep to update. */
{
# define LOCAL_SIZE 64
char localFlags[LOCAL_SIZE], *flagPtr = NULL;
List *listRepPtr = ListRepPtr(listPtr);
int numElems = listRepPtr->elemCount;
int i, length, bytesNeeded = 0;
const char *elem;
char *dst;
Tcl_Obj **elemPtrs;
/*
* Mark the list as being canonical; although it will now have a string
* rep, it is one we derived through proper "canonical" quoting and so
* it's known to be free from nasties relating to [concat] and [eval].
*/
listRepPtr->canonicalFlag = 1;
/*
* Handle empty list case first, so rest of the routine is simpler.
*/
if (numElems == 0) {
listPtr->bytes = tclEmptyStringRep;
listPtr->length = 0;
return;
}
/*
* Pass 1: estimate space, gather flags.
*/
if (numElems <= LOCAL_SIZE) {
flagPtr = localFlags;
} else {
/*
* We know numElems <= LIST_MAX, so this is safe.
*/
flagPtr = ckalloc(numElems);
}
elemPtrs = &listRepPtr->elements;
for (i = 0; i < numElems; i++) {
flagPtr[i] = (i ? TCL_DONT_QUOTE_HASH : 0);
elem = TclGetStringFromObj(elemPtrs[i], &length);
bytesNeeded += TclScanElement(elem, length, flagPtr+i);
if (bytesNeeded < 0) {
Tcl_Panic("max size for a Tcl value (%d bytes) exceeded", INT_MAX);
}
}
if (bytesNeeded > INT_MAX - numElems + 1) {
Tcl_Panic("max size for a Tcl value (%d bytes) exceeded", INT_MAX);
}
bytesNeeded += numElems;
/*
* Pass 2: copy into string rep buffer.
*/
/*
* We used to set the string length here, relying on a presumed
* guarantee that the number of bytes TclScanElement() calls reported
* to be needed was a precise count and not an over-estimate, so long
* as the same flag values were passed to TclConvertElement().
*
* Then we saw [35a8f1c04a], where a bug in TclScanElement() caused
* that guarantee to fail. Rather than trust there are no more bugs,
* we set the length after the loop based on what was actually written,
* an not on what was predicted.
*
listPtr->length = bytesNeeded - 1;
*
*/
listPtr->bytes = ckalloc(bytesNeeded);
dst = listPtr->bytes;
for (i = 0; i < numElems; i++) {
flagPtr[i] |= (i ? TCL_DONT_QUOTE_HASH : 0);
elem = TclGetStringFromObj(elemPtrs[i], &length);
dst += TclConvertElement(elem, length, dst, flagPtr[i]);
*dst++ = ' ';
}
dst[-1] = '\0';
/* Here is the safe setting of the string length. */
listPtr->length = dst - 1 - listPtr->bytes;
if (flagPtr != localFlags) {
ckfree(flagPtr);
}
}
/*
* Local Variables:
* mode: c
* c-basic-offset: 4
* fill-column: 78
* End:
*/