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Diffstat (limited to 'dix/atom.c')
| -rw-r--r-- | dix/atom.c | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/dix/atom.c b/dix/atom.c new file mode 100644 index 000000000..d5c53d2e2 --- /dev/null +++ b/dix/atom.c @@ -0,0 +1,211 @@ +/*********************************************************** + +Copyright 1987, 1998 The Open Group + +Permission to use, copy, modify, distribute, and sell this software and its +documentation for any purpose is hereby granted without fee, provided that +the above copyright notice appear in all copies and that both that +copyright notice and this permission notice appear in supporting +documentation. + +The above copyright notice and this permission notice shall be included in +all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN +AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN +CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + +Except as contained in this notice, the name of The Open Group shall not be +used in advertising or otherwise to promote the sale, use or other dealings +in this Software without prior written authorization from The Open Group. + + +Copyright 1987 by Digital Equipment Corporation, Maynard, Massachusetts. + + All Rights Reserved + +Permission to use, copy, modify, and distribute this software and its +documentation for any purpose and without fee is hereby granted, +provided that the above copyright notice appear in all copies and that +both that copyright notice and this permission notice appear in +supporting documentation, and that the name of Digital not be +used in advertising or publicity pertaining to distribution of the +software without specific, written prior permission. + +DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING +ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL +DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR +ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, +WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, +ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS +SOFTWARE. + +******************************************************************/ + +/* $Xorg: atom.c,v 1.4 2001/02/09 02:04:39 xorgcvs Exp $ */ + +#include "X.h" +#include "Xatom.h" +#include "misc.h" +#include "resource.h" + +#define InitialTableSize 100 + +typedef struct _Node { + struct _Node *left, *right; + Atom a; + unsigned int fingerPrint; + char *string; +} NodeRec, *NodePtr; + +static Atom lastAtom = None; +static NodePtr atomRoot = (NodePtr)NULL; +static unsigned long tableLength; +static NodePtr *nodeTable; + +Atom +MakeAtom(string, len, makeit) + char *string; + unsigned len; + Bool makeit; +{ + register NodePtr * np; + unsigned i; + int comp; + register unsigned int fp = 0; + + np = &atomRoot; + for (i = 0; i < (len+1)/2; i++) + { + fp = fp * 27 + string[i]; + fp = fp * 27 + string[len - 1 - i]; + } + while (*np != (NodePtr) NULL) + { + if (fp < (*np)->fingerPrint) + np = &((*np)->left); + else if (fp > (*np)->fingerPrint) + np = &((*np)->right); + else + { /* now start testing the strings */ + comp = strncmp(string, (*np)->string, (int)len); + if ((comp < 0) || ((comp == 0) && (len < strlen((*np)->string)))) + np = &((*np)->left); + else if (comp > 0) + np = &((*np)->right); + else + return(*np)->a; + } + } + if (makeit) + { + register NodePtr nd; + + nd = (NodePtr) xalloc(sizeof(NodeRec)); + if (!nd) + return BAD_RESOURCE; + if (lastAtom < XA_LAST_PREDEFINED) + { + nd->string = string; + } + else + { + nd->string = (char *) xalloc(len + 1); + if (!nd->string) { + xfree(nd); + return BAD_RESOURCE; + } + strncpy(nd->string, string, (int)len); + nd->string[len] = 0; + } + if ((lastAtom + 1) >= tableLength) { + NodePtr *table; + + table = (NodePtr *) xrealloc(nodeTable, + tableLength * (2 * sizeof(NodePtr))); + if (!table) { + if (nd->string != string) + xfree(nd->string); + xfree(nd); + return BAD_RESOURCE; + } + tableLength <<= 1; + nodeTable = table; + } + *np = nd; + nd->left = nd->right = (NodePtr) NULL; + nd->fingerPrint = fp; + nd->a = (++lastAtom); + *(nodeTable+lastAtom) = nd; + return nd->a; + } + else + return None; +} + +Bool +ValidAtom(atom) + Atom atom; +{ + return (atom != None) && (atom <= lastAtom); +} + +char * +NameForAtom(atom) + Atom atom; +{ + NodePtr node; + if (atom > lastAtom) return 0; + if ((node = nodeTable[atom]) == (NodePtr)NULL) return 0; + return node->string; +} + +void +AtomError() +{ + FatalError("initializing atoms"); +} + +void +FreeAtom(patom) + NodePtr patom; +{ + if(patom->left) + FreeAtom(patom->left); + if(patom->right) + FreeAtom(patom->right); + if (patom->a > XA_LAST_PREDEFINED) + xfree(patom->string); + xfree(patom); +} + +void +FreeAllAtoms() +{ + if(atomRoot == (NodePtr)NULL) + return; + FreeAtom(atomRoot); + atomRoot = (NodePtr)NULL; + xfree(nodeTable); + nodeTable = (NodePtr *)NULL; + lastAtom = None; +} + +void +InitAtoms() +{ + FreeAllAtoms(); + tableLength = InitialTableSize; + nodeTable = (NodePtr *)xalloc(InitialTableSize*sizeof(NodePtr)); + if (!nodeTable) + AtomError(); + nodeTable[None] = (NodePtr)NULL; + MakePredeclaredAtoms(); + if (lastAtom != XA_LAST_PREDEFINED) + AtomError (); +} + + |