1/*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation.  Oracle designates this
7 * particular file as subject to the "Classpath" exception as provided
8 * by Oracle in the LICENSE file that accompanied this code.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 */
24
25/*
26 * This file is available under and governed by the GNU General Public
27 * License version 2 only, as published by the Free Software Foundation.
28 * However, the following notice accompanied the original version of this
29 * file:
30 *
31 * ASM: a very small and fast Java bytecode manipulation framework
32 * Copyright (c) 2000-2011 INRIA, France Telecom
33 * All rights reserved.
34 *
35 * Redistribution and use in source and binary forms, with or without
36 * modification, are permitted provided that the following conditions
37 * are met:
38 * 1. Redistributions of source code must retain the above copyright
39 *    notice, this list of conditions and the following disclaimer.
40 * 2. Redistributions in binary form must reproduce the above copyright
41 *    notice, this list of conditions and the following disclaimer in the
42 *    documentation and/or other materials provided with the distribution.
43 * 3. Neither the name of the copyright holders nor the names of its
44 *    contributors may be used to endorse or promote products derived from
45 *    this software without specific prior written permission.
46 *
47 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
48 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
49 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
50 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
51 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
52 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
53 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
54 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
55 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
56 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
57 * THE POSSIBILITY OF SUCH DAMAGE.
58 */
59package jdk.internal.org.objectweb.asm;
60
61/**
62 * Information about an exception handler block.
63 *
64 * @author Eric Bruneton
65 */
66class Handler {
67
68    /**
69     * Beginning of the exception handler's scope (inclusive).
70     */
71    Label start;
72
73    /**
74     * End of the exception handler's scope (exclusive).
75     */
76    Label end;
77
78    /**
79     * Beginning of the exception handler's code.
80     */
81    Label handler;
82
83    /**
84     * Internal name of the type of exceptions handled by this handler, or
85     * <tt>null</tt> to catch any exceptions.
86     */
87    String desc;
88
89    /**
90     * Constant pool index of the internal name of the type of exceptions
91     * handled by this handler, or 0 to catch any exceptions.
92     */
93    int type;
94
95    /**
96     * Next exception handler block info.
97     */
98    Handler next;
99
100    /**
101     * Removes the range between start and end from the given exception
102     * handlers.
103     *
104     * @param h
105     *            an exception handler list.
106     * @param start
107     *            the start of the range to be removed.
108     * @param end
109     *            the end of the range to be removed. Maybe null.
110     * @return the exception handler list with the start-end range removed.
111     */
112    static Handler remove(Handler h, Label start, Label end) {
113        if (h == null) {
114            return null;
115        } else {
116            h.next = remove(h.next, start, end);
117        }
118        int hstart = h.start.position;
119        int hend = h.end.position;
120        int s = start.position;
121        int e = end == null ? Integer.MAX_VALUE : end.position;
122        // if [hstart,hend[ and [s,e[ intervals intersect...
123        if (s < hend && e > hstart) {
124            if (s <= hstart) {
125                if (e >= hend) {
126                    // [hstart,hend[ fully included in [s,e[, h removed
127                    h = h.next;
128                } else {
129                    // [hstart,hend[ minus [s,e[ = [e,hend[
130                    h.start = end;
131                }
132            } else if (e >= hend) {
133                // [hstart,hend[ minus [s,e[ = [hstart,s[
134                h.end = start;
135            } else {
136                // [hstart,hend[ minus [s,e[ = [hstart,s[ + [e,hend[
137                Handler g = new Handler();
138                g.start = end;
139                g.end = h.end;
140                g.handler = h.handler;
141                g.desc = h.desc;
142                g.type = h.type;
143                g.next = h.next;
144                h.end = start;
145                h.next = g;
146            }
147        }
148        return h;
149    }
150}
151