1 /***********************************************************
2
3 Copyright 1987, 1998 The Open Group
4
5 Permission to use, copy, modify, distribute, and sell this software and its
6 documentation for any purpose is hereby granted without fee, provided that
7 the above copyright notice appear in all copies and that both that
8 copyright notice and this permission notice appear in supporting
9 documentation.
10
11 The above copyright notice and this permission notice shall be included in
12 all copies or substantial portions of the Software.
13
14 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
17 OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
18 AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
19 CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
20
21 Except as contained in this notice, the name of The Open Group shall not be
22 used in advertising or otherwise to promote the sale, use or other dealings
23 in this Software without prior written authorization from The Open Group.
24
25 Copyright 1987 by Digital Equipment Corporation, Maynard, Massachusetts.
26
27 All Rights Reserved
28
29 Permission to use, copy, modify, and distribute this software and its
30 documentation for any purpose and without fee is hereby granted,
31 provided that the above copyright notice appear in all copies and that
32 both that copyright notice and this permission notice appear in
33 supporting documentation, and that the name of Digital not be
34 used in advertising or publicity pertaining to distribution of the
35 software without specific, written prior permission.
36
37 DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
38 ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
39 DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
40 ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
41 WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
42 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
43 SOFTWARE.
44
45 ******************************************************************/
46
47 #ifdef HAVE_DIX_CONFIG_H
48 #include <dix-config.h>
49 #endif
50
51 #include <X11/X.h>
52 #include <X11/Xatom.h>
53 #include <stdio.h>
54 #include <string.h>
55 #include "misc.h"
56 #include "resource.h"
57 #include "dix.h"
58
59 #define InitialTableSize 256
60
61 typedef struct _Node {
62 struct _Node *left, *right;
63 Atom a;
64 unsigned int fingerPrint;
65 const char *string;
66 } NodeRec, *NodePtr;
67
68 static Atom lastAtom = None;
69 static NodePtr atomRoot = NULL;
70 static unsigned long tableLength;
71 static NodePtr *nodeTable;
72
73 Atom
MakeAtom(const char * string,unsigned len,Bool makeit)74 MakeAtom(const char *string, unsigned len, Bool makeit)
75 {
76 NodePtr *np;
77 unsigned i;
78 int comp;
79 unsigned int fp = 0;
80
81 np = &atomRoot;
82 for (i = 0; i < (len + 1) / 2; i++) {
83 fp = fp * 27 + string[i];
84 fp = fp * 27 + string[len - 1 - i];
85 }
86 while (*np != NULL) {
87 if (fp < (*np)->fingerPrint)
88 np = &((*np)->left);
89 else if (fp > (*np)->fingerPrint)
90 np = &((*np)->right);
91 else { /* now start testing the strings */
92 comp = strncmp(string, (*np)->string, (int) len);
93 if ((comp < 0) || ((comp == 0) && (len < strlen((*np)->string))))
94 np = &((*np)->left);
95 else if (comp > 0)
96 np = &((*np)->right);
97 else
98 return (*np)->a;
99 }
100 }
101 if (makeit) {
102 NodePtr nd;
103
104 nd = malloc(sizeof(NodeRec));
105 if (!nd)
106 return BAD_RESOURCE;
107 if (lastAtom < XA_LAST_PREDEFINED) {
108 nd->string = string;
109 }
110 else {
111 nd->string = strndup(string, len);
112 if (!nd->string) {
113 free(nd);
114 return BAD_RESOURCE;
115 }
116 }
117 if ((lastAtom + 1) >= tableLength) {
118 NodePtr *table;
119
120 table = reallocarray(nodeTable, tableLength, 2 * sizeof(NodePtr));
121 if (!table) {
122 if (nd->string != string) {
123 /* nd->string has been strdup'ed */
124 free((char *) nd->string);
125 }
126 free(nd);
127 return BAD_RESOURCE;
128 }
129 tableLength <<= 1;
130 nodeTable = table;
131 }
132 *np = nd;
133 nd->left = nd->right = NULL;
134 nd->fingerPrint = fp;
135 nd->a = ++lastAtom;
136 nodeTable[lastAtom] = nd;
137 return nd->a;
138 }
139 else
140 return None;
141 }
142
143 Bool
ValidAtom(Atom atom)144 ValidAtom(Atom atom)
145 {
146 return (atom != None) && (atom <= lastAtom);
147 }
148
149 const char *
NameForAtom(Atom atom)150 NameForAtom(Atom atom)
151 {
152 NodePtr node;
153
154 if (atom > lastAtom)
155 return 0;
156 if ((node = nodeTable[atom]) == NULL)
157 return 0;
158 return node->string;
159 }
160
161 void
AtomError(void)162 AtomError(void)
163 {
164 FatalError("initializing atoms");
165 }
166
167 static void
FreeAtom(NodePtr patom)168 FreeAtom(NodePtr patom)
169 {
170 if (patom->left)
171 FreeAtom(patom->left);
172 if (patom->right)
173 FreeAtom(patom->right);
174 if (patom->a > XA_LAST_PREDEFINED) {
175 /*
176 * All strings above XA_LAST_PREDEFINED are strdup'ed, so it's safe to
177 * cast here
178 */
179 free((char *) patom->string);
180 }
181 free(patom);
182 }
183
184 void
FreeAllAtoms(void)185 FreeAllAtoms(void)
186 {
187 if (atomRoot == NULL)
188 return;
189 FreeAtom(atomRoot);
190 atomRoot = NULL;
191 free(nodeTable);
192 nodeTable = NULL;
193 lastAtom = None;
194 }
195
196 void
InitAtoms(void)197 InitAtoms(void)
198 {
199 FreeAllAtoms();
200 tableLength = InitialTableSize;
201 nodeTable = xallocarray(InitialTableSize, sizeof(NodePtr));
202 if (!nodeTable)
203 AtomError();
204 nodeTable[None] = NULL;
205 MakePredeclaredAtoms();
206 if (lastAtom != XA_LAST_PREDEFINED)
207 AtomError();
208 }
209