| [d7d2da3] | 1 | /*
|
|---|
| 2 | * tclPreserve.c --
|
|---|
| 3 | *
|
|---|
| 4 | * This file contains a collection of procedures that are used
|
|---|
| 5 | * to make sure that widget records and other data structures
|
|---|
| 6 | * aren't reallocated when there are nested procedures that
|
|---|
| 7 | * depend on their existence.
|
|---|
| 8 | *
|
|---|
| 9 | * Copyright (c) 1991-1994 The Regents of the University of California.
|
|---|
| 10 | * Copyright (c) 1994-1995 Sun Microsystems, Inc.
|
|---|
| 11 | *
|
|---|
| 12 | * See the file "license.terms" for information on usage and redistribution
|
|---|
| 13 | * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
|
|---|
| 14 | *
|
|---|
| 15 | * RCS: @(#) $Id: tclPreserve.c,v 1.1 2008-06-04 13:58:10 demin Exp $
|
|---|
| 16 | */
|
|---|
| 17 |
|
|---|
| 18 | #include "tclInt.h"
|
|---|
| 19 |
|
|---|
| 20 | /*
|
|---|
| 21 | * The following data structure is used to keep track of all the
|
|---|
| 22 | * Tcl_Preserve calls that are still in effect. It grows as needed
|
|---|
| 23 | * to accommodate any number of calls in effect.
|
|---|
| 24 | */
|
|---|
| 25 |
|
|---|
| 26 | typedef struct {
|
|---|
| 27 | ClientData clientData; /* Address of preserved block. */
|
|---|
| 28 | int refCount; /* Number of Tcl_Preserve calls in effect
|
|---|
| 29 | * for block. */
|
|---|
| 30 | int mustFree; /* Non-zero means Tcl_EventuallyFree was
|
|---|
| 31 | * called while a Tcl_Preserve call was in
|
|---|
| 32 | * effect, so the structure must be freed
|
|---|
| 33 | * when refCount becomes zero. */
|
|---|
| 34 | Tcl_FreeProc *freeProc; /* Procedure to call to free. */
|
|---|
| 35 | } Reference;
|
|---|
| 36 |
|
|---|
| 37 | static Reference *refArray; /* First in array of references. */
|
|---|
| 38 | static int inUse = 0; /* Count of structures currently in use
|
|---|
| 39 | * in refArray. */
|
|---|
| 40 | #define INITIAL_SIZE 2
|
|---|
| 41 |
|
|---|
| 42 | /*
|
|---|
| 43 | *----------------------------------------------------------------------
|
|---|
| 44 | *
|
|---|
| 45 | * Tcl_EventuallyFree --
|
|---|
| 46 | *
|
|---|
| 47 | * Free up a block of memory, unless a call to Tcl_Preserve is in
|
|---|
| 48 | * effect for that block. In this case, defer the free until all
|
|---|
| 49 | * calls to Tcl_Preserve have been undone by matching calls to
|
|---|
| 50 | * Tcl_Release.
|
|---|
| 51 | *
|
|---|
| 52 | * Results:
|
|---|
| 53 | * None.
|
|---|
| 54 | *
|
|---|
| 55 | * Side effects:
|
|---|
| 56 | * Ptr may be released by calling free().
|
|---|
| 57 | *
|
|---|
| 58 | *----------------------------------------------------------------------
|
|---|
| 59 | */
|
|---|
| 60 |
|
|---|
| 61 | void
|
|---|
| 62 | Tcl_EventuallyFree(clientData, freeProc)
|
|---|
| 63 | ClientData clientData; /* Pointer to malloc'ed block of memory. */
|
|---|
| 64 | Tcl_FreeProc *freeProc; /* Procedure to actually do free. */
|
|---|
| 65 | {
|
|---|
| 66 | Reference *refPtr;
|
|---|
| 67 | int i;
|
|---|
| 68 |
|
|---|
| 69 | /*
|
|---|
| 70 | * See if there is a reference for this pointer. If so, set its
|
|---|
| 71 | * "mustFree" flag (the flag had better not be set already!).
|
|---|
| 72 | */
|
|---|
| 73 |
|
|---|
| 74 | for (i = 0, refPtr = refArray; i < inUse; i++, refPtr++) {
|
|---|
| 75 | if (refPtr->clientData != clientData) {
|
|---|
| 76 | continue;
|
|---|
| 77 | }
|
|---|
| 78 | if (refPtr->mustFree) {
|
|---|
| 79 | panic("Tcl_EventuallyFree called twice for 0x%x\n", clientData);
|
|---|
| 80 | }
|
|---|
| 81 | refPtr->mustFree = 1;
|
|---|
| 82 | refPtr->freeProc = freeProc;
|
|---|
| 83 | return;
|
|---|
| 84 | }
|
|---|
| 85 |
|
|---|
| 86 | /*
|
|---|
| 87 | * No reference for this block. Free it now.
|
|---|
| 88 | */
|
|---|
| 89 |
|
|---|
| 90 | if ((freeProc == TCL_DYNAMIC)
|
|---|
| 91 | || (freeProc == (Tcl_FreeProc *) free)) {
|
|---|
| 92 | ckfree((char *) clientData);
|
|---|
| 93 | } else {
|
|---|
| 94 | (*freeProc)((char *)clientData);
|
|---|
| 95 | }
|
|---|
| 96 | }
|
|---|
