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Diffstat (limited to 'tcl8.6/generic/tclListObj.c')
| -rw-r--r-- | tcl8.6/generic/tclListObj.c | 2040 |
1 files changed, 2040 insertions, 0 deletions
diff --git a/tcl8.6/generic/tclListObj.c b/tcl8.6/generic/tclListObj.c new file mode 100644 index 0000000..14b8a14 --- /dev/null +++ b/tcl8.6/generic/tclListObj.c @@ -0,0 +1,2040 @@ +/* + * 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 internal rep with space for objc elements. objc + * must be > 0. If objv!=NULL, initializes with the first objc values + * in that array. If objv==NULL, initalize list internal rep to have + * 0 elements, with space to add objc more. Flag value "p" indicates + * how to behave on failure. + * + * Results: + * A new List struct with refCount 0 is returned. If some failure + * prevents this then if p=0, NULL is returned and otherwise the + * routine panics. + * + * Side effects: + * The ref counts of the elements in objv are incremented since the + * resulting list now refers to them. + * + *---------------------------------------------------------------------- + */ + +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 -- + * + * Creates a list internal rep with space for objc elements. objc + * must be > 0. If objv!=NULL, initializes with the first objc values + * in that array. If objv==NULL, initalize list internal rep to have + * 0 elements, with space to add objc more. + * + * Results: + * A new List struct with refCount 0 is returned. If some failure + * prevents this then NULL is returned, and an error message is left + * in the interp result, unless interp is NULL. + * + * Side effects: + * The ref counts of the elements in objv are incremented since the + * resulting list now refers to them. + * + *---------------------------------------------------------------------- + */ + +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 -- + * + * This function is normally called when not debugging: i.e., when + * TCL_MEM_DEBUG is not defined. It creates a new list object from an + * (objc,objv) array: that is, each of the objc elements of the array + * referenced by objv is inserted as an element into a new Tcl object. + * + * When TCL_MEM_DEBUG is defined, this function just returns the result + * of calling the debugging version Tcl_DbNewListObj. + * + * Results: + * A new list object is returned that is initialized from the object + * pointers in objv. If objc is less than or equal to zero, an empty + * object is returned. The new object's string representation is left + * NULL. The resulting new list object has ref count 0. + * + * Side effects: + * The ref counts of the elements in objv are incremented since the + * resulting list now refers to them. + * + *---------------------------------------------------------------------- + */ + +#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 -- + * + * This function is normally called when debugging: i.e., when + * TCL_MEM_DEBUG is defined. It creates new list objects. It is the same + * as the Tcl_NewListObj function above except that it calls + * Tcl_DbCkalloc directly with the file name and line number from its + * caller. This simplifies debugging since then 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, this function just returns the + * result of calling Tcl_NewListObj. + * + * Results: + * A new list object is returned that is initialized from the object + * pointers in objv. If objc is less than or equal to zero, an empty + * object is returned. The new object's string representation is left + * NULL. The new list object has ref count 0. + * + * Side effects: + * The ref counts of the elements in objv are incremented since the + * resulting list now refers to them. + * + *---------------------------------------------------------------------- + */ + +#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 -- + * + * Modify an object to be a list containing each of the objc elements of + * the object array referenced by objv. + * + * Results: + * None. + * + * Side effects: + * The object is made a list object and is initialized from the object + * pointers in objv. If objc is less than or equal to zero, an empty + * object is returned. The new object's string representation is left + * NULL. The ref counts of the elements in objv are incremented since the + * list now refers to them. The object's old string and internal + * representations are freed and its type is set NULL. + * + *---------------------------------------------------------------------- + */ + +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 -- + * + * Makes a "pure list" 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. + * + * Results: + * Normally returns a pointer to a new Tcl_Obj, that contains the same + * list value as *listPtr does. The returned Tcl_Obj has a refCount of + * zero. If *listPtr does not hold a list, NULL is returned, and if + * interp is non-NULL, an error message is recorded there. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +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 -- + * + * This function returns an (objc,objv) array of the elements in a list + * object. + * + * Results: + * The return value is normally TCL_OK; in this case *objcPtr is set to + * the count of list elements and *objvPtr is set to a pointer to an + * array of (*objcPtr) pointers to each list element. If listPtr does not + * refer to a list object and the object can not be converted to one, + * TCL_ERROR is returned and an error message will be left in the + * interpreter's result if interp is not NULL. + * + * The objects referenced by the returned array should be treated as + * readonly and their ref counts are _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. + * + * Side effects: + * The possible conversion of the object referenced by listPtr + * to a list object. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_ListObjGetElements( + Tcl_Interp *interp, /* Used to report errors if not NULL. */ + register 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. */ +{ + register 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 -- + * + * This function appends the elements in the list value referenced by + * elemListPtr to the list value referenced by listPtr. + * + * Results: + * The return value is normally TCL_OK. If listPtr or elemListPtr do not + * refer to list values, TCL_ERROR is returned and an error message is + * left in the interpreter's result if interp is not NULL. + * + * Side effects: + * The reference counts of the elements in elemListPtr are incremented + * since the list now refers to them. listPtr and elemListPtr are + * converted, if necessary, to list objects. Also, appending the new + * elements may cause listObj's array of element pointers to grow. + * listPtr's old string representation, if any, is invalidated. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_ListObjAppendList( + Tcl_Interp *interp, /* Used to report errors if not NULL. */ + register 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 -- + * + * This function is a special purpose version of Tcl_ListObjAppendList: + * it appends a single object referenced by objPtr to the list object + * referenced by listPtr. If listPtr is not already a list object, an + * attempt will be made to convert it to one. + * + * Results: + * The return value is normally TCL_OK; in this case objPtr is added to + * the end of listPtr's list. If listPtr does not refer to a list object + * and the object can not be converted to one, TCL_ERROR is returned and + * an error message will be left in the interpreter's result if interp is + * not NULL. + * + * Side effects: + * The ref count of objPtr is incremented since the list now refers to + * it. listPtr will be converted, if necessary, to a list object. Also, + * appending the new element may cause listObj's array of element + * pointers to grow. listPtr's old string representation, if any, 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. */ +{ + register 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, (size_t) 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 -- + * + * This function returns a pointer to the index'th object from the list + * referenced by listPtr. The first element has index 0. If index is + * negative or greater than or equal to the number of elements in the + * list, a NULL is returned. If listPtr is not a list object, an attempt + * will be made to convert it to a list. + * + * Results: + * The return value is normally TCL_OK; in this case objPtrPtr is set to + * the Tcl_Obj pointer for the index'th list element or NULL if index is + * out of range. This object should be treated as readonly and its ref + * count is _not_ incremented; the caller must do that if it holds on to + * the reference. If listPtr does not refer to a list and can't be + * converted to one, TCL_ERROR is returned and an error message is left + * in the interpreter's result if interp is not NULL. + * + * Side effects: + * listPtr will be converted, if necessary, to a list object. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_ListObjIndex( + Tcl_Interp *interp, /* Used to report errors if not NULL. */ + register Tcl_Obj *listPtr, /* List object to index into. */ + register int index, /* Index of element to return. */ + Tcl_Obj **objPtrPtr) /* The resulting Tcl_Obj* is stored here. */ +{ + register 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 -- + * + * This function returns the number of elements in a list object. If the + * object is not already a list object, an attempt will be made to + * convert it to one. + * + * Results: + * The return value is normally TCL_OK; in this case *intPtr will be set + * to the integer count of list elements. If listPtr does not refer to a + * list object and the object can not be converted to one, TCL_ERROR is + * returned and an error message will be left in the interpreter's result + * if interp is not NULL. + * + * Side effects: + * The possible conversion of the argument object to a list object. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_ListObjLength( + Tcl_Interp *interp, /* Used to report errors if not NULL. */ + register Tcl_Obj *listPtr, /* List object whose #elements to return. */ + register int *intPtr) /* The resulting int is stored here. */ +{ + register 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 -- + * + * This function replaces zero or more elements of the list referenced by + * listPtr with the objects from an (objc,objv) array. The objc elements + * of the array referenced by objv replace the count elements in listPtr + * starting at first. + * + * If the argument first is zero or negative, it refers to the first + * element. If first is greater than or equal to the number of elements + * in the list, then no elements are deleted; the new elements are + * appended to the list. Count gives the number of elements to replace. + * If count is zero or negative then no elements are deleted; the new + * elements are simply inserted before first. + * + * The argument objv refers to an array of objc pointers to the new + * elements to be added to listPtr in place of those that were deleted. + * If objv is NULL, no new elements are added. If listPtr is not a list + * object, an attempt will be made to convert it to one. + * + * Results: + * The return value is normally TCL_OK. If listPtr does not refer to a + * list object and can not be converted to one, TCL_ERROR is returned and + * an error message will be left in the interpreter's result if interp is + * not NULL. + * + * Side effects: + * The ref counts of the objc elements in objv are incremented since the + * resulting list now refers to them. Similarly, the ref counts for + * replaced objects are decremented. listPtr is converted, if necessary, + * to a list object. listPtr's old string representation, if any, is + * freed. + * + *---------------------------------------------------------------------- + */ + +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; + register 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 (numElems < first+count || first+count < 0) { + /* + * The 'first+count < 0' condition here guards agains integer + * overflow in determining 'first+count'. + */ + + count = numElems - first; + } + + if (objc > LIST_MAX - (numElems - count)) { + 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, (size_t) 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, (size_t) 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 -- + * + * This procedure handles the 'lindex' command when objc==3. + * + * Results: + * Returns a pointer to the object extracted, or NULL if an error + * occurred. The returned object already includes one reference count for + * the pointer returned. + * + * Side effects: + * None. + * + * Notes: + * This procedure is implemented entirely as a wrapper around + * TclLindexFlat. All it does is reconfigure the argument format into the + * form required by TclLindexFlat, while taking care to manage shimmering + * in such a way that we tend to keep the most useful intreps and/or + * avoid the most expensive conversions. + * + *---------------------------------------------------------------------- + */ + +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); + } + + if (indexListCopy->typePtr == &tclListType) { + List *listRepPtr = ListRepPtr(indexListCopy); + + listPtr = TclLindexFlat(interp, listPtr, listRepPtr->elemCount, + &listRepPtr->elements); + } else { + int indexCount = -1; /* Size of the array of list indices. */ + Tcl_Obj **indices = NULL; + /* Array of list indices. */ + + Tcl_ListObjGetElements(NULL, indexListCopy, &indexCount, &indices); + listPtr = TclLindexFlat(interp, listPtr, indexCount, indices); + } + Tcl_DecrRefCount(indexListCopy); + return listPtr; +} + +/* + *---------------------------------------------------------------------- + * + * TclLindexFlat -- + * + * This procedure is the core of the 'lindex' command, with all index + * arguments presented as a flat list. + * + * Results: + * Returns a pointer to the object extracted, or NULL if an error + * occurred. The returned object already includes one reference count for + * the pointer returned. + * + * Side effects: + * None. + * + * Notes: + * The reference count of the returned object includes one reference + * corresponding to the pointer returned. 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; + } + } + listPtr = Tcl_NewObj(); + } else { + /* + * Extract the pointer to the appropriate element. + */ + + listPtr = elemPtrs[index]; + } + Tcl_IncrRefCount(listPtr); + } + Tcl_DecrRefCount(sublistCopy); + } + + return listPtr; +} + +/* + *---------------------------------------------------------------------- + * + * TclLsetList -- + * + * Core of the 'lset' command when objc == 4. Objv[2] may be either a + * scalar index or a list of indices. + * + * Results: + * Returns the new value of the list variable, or NULL if there was an + * error. The returned object includes one reference count for the + * pointer returned. + * + * Side effects: + * None. + * + * Notes: + * This procedure is implemented entirely as a wrapper around + * TclLsetFlat. All it does is reconfigure the argument format into the + * form required by TclLsetFlat, while taking care to manage shimmering + * in such a way that we tend to keep the most useful intreps and/or + * avoid the most expensive conversions. + * + *---------------------------------------------------------------------- + */ + +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. + * + * Results: + * Returns the new value of the list variable, or NULL if an error + * occurred. The returned object includes one reference count for the + * pointer returned. + * + * Side effects: + * On entry, the reference count of the variable value does not reflect + * any references held on the stack. The first action of this function is + * to determine whether the object is shared, and to duplicate it if it + * is. The reference count of the duplicate is incremented. At this + * point, the reference count will be 1 for either case, so that the + * object will appear to be unshared. + * + * If an error occurs, and the object has been duplicated, the reference + * count on the duplicate is decremented so that it is now 0: this + * dismisses any memory that was allocated by this function. + * + * If no error occurs, the reference count of the original object is + * incremented if the object has not been duplicated, and nothing is done + * to a reference count of the duplicate. Now the reference count of an + * unduplicated object is 2 (the returned pointer, plus the one stored in + * the variable). The reference count of a duplicate object is 1, + * reflecting that the returned pointer is the only active reference. The + * caller is expected to store the returned value back in the variable + * and decrement its reference count. (INST_STORE_* does exactly this.) + * + * Surgery is performed on the unshared list value to produce the result. + * TclLsetFlat maintains a linked list of Tcl_Obj's 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) { + subListPtr = Tcl_NewObj(); + } 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 + * + * Results: + * The return value is normally TCL_OK. If listPtr does not refer to a + * list object and cannot be converted to one, TCL_ERROR is returned and + * an error message will be left in the interpreter result if interp is + * not NULL. Similarly, if index designates an element outside the range + * [0..listLength-1], where listLength is the count of elements in the + * list object designated by listPtr, TCL_ERROR is returned and an error + * message is left in the interpreter result. + * + * Side effects: + * Tcl_Panic if listPtr designates a shared object. Otherwise, attempts + * to convert it to a list with a non-shared internal rep. Decrements the + * ref count of the object at the specified index within the list, + * replaces with the object designated by valuePtr, and increments the + * ref count of the replacement object. + * + * It is the caller's responsibility to invalidate the string + * representation of the object. + * + *---------------------------------------------------------------------- + */ + +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 a list object's internal + * representation. + * + * Results: + * None. + * + * Side effects: + * Frees listPtr's List* internal representation and sets listPtr's + * internalRep.twoPtrValue.ptr1 to NULL. Decrements the ref counts of all + * element objects, which may free them. + * + *---------------------------------------------------------------------- + */ + +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. + * + * Results: + * None. + * + * Side effects: + * The reference count 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 -- + * + * Attempt to generate a list internal form for the Tcl object "objPtr". + * + * Results: + * The return value is TCL_OK or TCL_ERROR. If an error occurs during + * conversion, an error message is left in the interpreter's result + * unless "interp" is NULL. + * + * Side effects: + * If no error occurs, a list is stored as "objPtr"s internal + * representation. + * + *---------------------------------------------------------------------- + */ + +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. Note: This + * function does not invalidate an existing old string rep so storage + * will be lost if this has not already been done. + * + * Results: + * None. + * + * Side effects: + * The object's string is set to a valid string that results from the + * list-to-string conversion. This string will be empty if the list has + * no elements. The list internal representation should not be NULL and + * we assume it is not NULL. + * + *---------------------------------------------------------------------- + */ + +static void +UpdateStringOfList( + Tcl_Obj *listPtr) /* List object with string rep to update. */ +{ +# define LOCAL_SIZE 20 + int 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 * sizeof(int)); + } + 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. + */ + + 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++ = ' '; + } + listPtr->bytes[listPtr->length] = '\0'; + + if (flagPtr != localFlags) { + ckfree(flagPtr); + } +} + +/* + * Local Variables: + * mode: c + * c-basic-offset: 4 + * fill-column: 78 + * End: + */ |