1 /*
2 * Copyright (c) 2014, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 /*
25 * @test
26 * @bug 6762191
27 * @summary Setting stack size to 16K causes segmentation fault
28 * @modules java.compiler
29 * @compile TooSmallStackSize.java
30 * @run main TooSmallStackSize
31 */
32
33 /*
34 * The primary purpose of this test is to make sure we can run with a 16k stack
35 * size without crashing. Also this test will determine the minimum allowed
36 * stack size for the platform (as provided by the JVM error message when a very
37 * small stack is used), and then verify that the JVM can be launched with that stack
38 * size without a crash or any error messages.
39 *
40 * Note: The '-Xss<size>' and '-XX:ThreadStackSize=<k-bytes>' options
41 * both control Java thread stack size. This repo's version of the test
42 * exercises the '-Xss' option. The hotspot repo's version of the test
43 * exercises the '-XX:ThreadStackSize' VM option.
44 */
45
46 public class TooSmallStackSize extends TestHelper {
47 /* for debugging. Normally false. */
48 static final boolean verbose = false;
49
50 static void printTestOutput(TestResult tr) {
51 System.out.println("*** exitValue = " + tr.exitValue);
52 for (String x : tr.testOutput) {
53 System.out.println(x);
54 }
55 }
56
57 /*
58 * Returns the minimum stack size this platform will allowed based on the
59 * contents of the error message the JVM outputs when too small of a
60 * -Xss size was used.
61 *
62 * The TestResult argument must contain the result of having already run
63 * the JVM with too small of a stack size.
64 */
65 static String getMinStackAllowed(TestResult tr) {
66 /*
67 * The JVM output will contain in one of the lines:
68 * "The Java thread stack size specified is too small. Specify at least 100k"
69 * Although the actual size will vary. We need to extract this size
70 * string from the output and return it.
71 */
72 String matchStr = "Specify at least ";
73 for (String x : tr.testOutput) {
74 int match_idx = x.indexOf(matchStr);
75 if (match_idx >= 0) {
76 int size_start_idx = match_idx + matchStr.length();
77 int k_start_idx = x.indexOf("k", size_start_idx);
78 return x.substring(size_start_idx, k_start_idx + 1); // include the "k"
79 }
80 }
81
82 System.out.println("Expect='" + matchStr + "'");
83 System.out.println("Actual:");
84 printTestOutput(tr);
85 System.out.println("FAILED: Could not get the stack size from the output");
86 throw new RuntimeException("test fails");
87 }
88
89 /*
90 * Run the JVM with the specified stack size.
91 *
92 * Returns the minimum allowed stack size gleaned from the error message,
93 * if there is an error message. Otherwise returns the stack size passed in.
94 */
95 static String checkStack(String stackSize) {
96 String min_stack_allowed;
97
98 if (verbose)
99 System.out.println("*** Testing " + stackSize);
100 TestResult tr = doExec(javaCmd, "-Xss" + stackSize, "-version");
101 if (verbose)
102 printTestOutput(tr);
103
104 if (tr.isOK()) {
105 System.out.println("PASSED: got no error message with stack size of " + stackSize);
106 min_stack_allowed = stackSize;
107 } else {
108 String matchStr = "The Java thread stack size specified is too small";
109 if (tr.contains(matchStr)) {
110 System.out.println("PASSED: got expected error message with stack size of " + stackSize);
111 min_stack_allowed = getMinStackAllowed(tr);
112 } else {
113 // Likely a crash
114 System.out.println("Expect='" + matchStr + "'");
115 System.out.println("Actual:");
116 printTestOutput(tr);
117 System.out.println("FAILED: Did not get expected error message with stack size of " + stackSize);
118 throw new RuntimeException("test fails");
119 }
120 }
121
122 return min_stack_allowed;
123 }
124
125 /*
126 * Run the JVM with the minimum allowed stack size. This should always succeed.
127 */
128 static void checkMinStackAllowed(String stackSize) {
129 if (verbose)
130 System.out.println("*** Testing " + stackSize);
131 TestResult tr = doExec(javaCmd, "-Xss" + stackSize, "-version");
132 if (verbose)
133 printTestOutput(tr);
134
135 if (tr.isOK()) {
136 System.out.println("PASSED: VM launched with minimum allowed stack size of " + stackSize);
137 } else {
138 // Likely a crash
139 System.out.println("Test output:");
140 printTestOutput(tr);
141 System.out.println("FAILED: VM failed to launch with minimum allowed stack size of " + stackSize);
142 throw new RuntimeException("test fails");
143 }
144 }
145
146 public static void main(String... args) {
147 /*
148 * The result of a 16k stack size should be a quick exit with a complaint
149 * that the stack size is too small. However, for some win32 builds, the
150 * stack is always at least 64k, and this also sometimes is the minimum
151 * allowed size, so we won't see an error in this case.
152 *
153 * This test case will also produce a crash on some platforms if the fix
154 * for 6762191 is not yet in place.
155 */
156 checkStack("16k");
157
158 /*
159 * Try with a 32k stack size, which is the size that the launcher will
160 * set to if you try setting to anything smaller. This should produce the same
161 * result as setting to 16k if the fix for 6762191 is in place.
162 */
163 String min_stack_allowed = checkStack("32k");
164
165 /*
166 * Try again with a the minimum stack size that was given in the error message
167 */
168 checkMinStackAllowed(min_stack_allowed);
169 }
170 }