22 */
23
24 /* @test
25 * @bug 4763384
26 * @summary Ensure that piped input always works with exec'd processes
27 */
28
29 import java.io.*;
30
31
32 /**
33 * This class demonstrates a regression in java1.4.1 in the handling of the
34 * Process OutputStream (exec'd process stdin). The subprocess completes 100%
35 * of the time in 1.4, but about only about 50% of the time under 1.4.1. Issue
36 * exists for client JVM, Linux Redhat 6.2 not sure about other variants of
37 * Linux or other OSes, or server JVM.
38 */
39
40 public class ExecWithInput {
41
42 private static final String CAT = "/bin/cat";
43 private static final int N = 200;
44
45 static int go(int i) throws Exception {
46 /*
47 * Execute /bin/cat supplying two lines of input. cat should
48 * read the input lines and copy them to stdout. On completion,
49 * p.waitFor should return and the exit status is printed and this
50 * program exits. Under 1.4.1, cat sometimes gets stuck on a pipe
51 * read and never terminates.
52 */
53 //Process p = Runtime.getRuntime().exec(new String[] { CAT } );
54 Process p = Runtime.getRuntime().exec(CAT);
55
56 String input = i + ": line 1\n" + i + ": line 2\n";
57 StringBufferInputStream in = new StringBufferInputStream(input);
58 // create threads to handle I/O streams
59 IO ioIn = new IO("stdin", in, p.getOutputStream());
60 IO ioOut = new IO("stdout", p.getInputStream(), System.out);
61 IO ioErr = new IO("stderr", p.getErrorStream(), System.err);
62
63 // wait for process to exit
64 return p.waitFor();
65 }
66
67 public static void main(String[] args) throws Exception {
68 if (!System.getProperty("os.name").equals("Linux"))
69 return;
70 if (File.separatorChar == '\\') {
71 // no /bin/cat on windows
72 return;
73 }
74 for (int i = 0; i < N; i++)
75 go(i);
76 }
77
78 /**
79 * Handle IO. Thread is started in constructor.
80 */
81 static class IO extends Thread {
82
83 private InputStream in;
84 private OutputStream out;
85
86 IO(String name, InputStream in, OutputStream out)
87 {
88 this.in = in;
89 this.out = out;
90 setName(name);
91 start();
92 }
93
94 public void run() {
95 try {
96 int c;
97 byte[] buf = new byte[8192];
98 int n;
99 while ((n = in.read(buf)) != -1) {
100 out.write(buf, 0, n);
101 out.flush();
102 }
103 /*
104 while ((c = in.read()) != -1) {
105 out.write(c);
106 if (c == '\n')
107 out.flush();
108 }
109 out.flush();
110 */
111 } catch (IOException e) {
112 e.printStackTrace();
113 } finally {
114 if (!System.out.equals(out) && !System.err.equals(out)) {
115 // Note: in order to get an exec'd java process to
116 // see EOF on input, it is necessary to close stdin
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22 */
23
24 /* @test
25 * @bug 4763384
26 * @summary Ensure that piped input always works with exec'd processes
27 */
28
29 import java.io.*;
30
31
32 /**
33 * This class demonstrates a regression in java1.4.1 in the handling of the
34 * Process OutputStream (exec'd process stdin). The subprocess completes 100%
35 * of the time in 1.4, but about only about 50% of the time under 1.4.1. Issue
36 * exists for client JVM, Linux Redhat 6.2 not sure about other variants of
37 * Linux or other OSes, or server JVM.
38 */
39
40 public class ExecWithInput {
41
42 private static final int N = 200;
43
44 static int go(int i) throws Exception {
45 /*
46 * Execute /bin/cat supplying two lines of input. cat should
47 * read the input lines and copy them to stdout. On completion,
48 * p.waitFor should return and the exit status is printed and this
49 * program exits. Under 1.4.1, cat sometimes gets stuck on a pipe
50 * read and never terminates.
51 */
52 Process p = Runtime.getRuntime().exec(UnixCommands.cat());
53
54 String input = i + ": line 1\n" + i + ": line 2\n";
55 StringBufferInputStream in = new StringBufferInputStream(input);
56 // create threads to handle I/O streams
57 IO ioIn = new IO("stdin", in, p.getOutputStream());
58 IO ioOut = new IO("stdout", p.getInputStream(), System.out);
59 IO ioErr = new IO("stderr", p.getErrorStream(), System.err);
60
61 // wait for process to exit
62 return p.waitFor();
63 }
64
65 public static void main(String[] args) throws Exception {
66 if (! UnixCommands.isLinux) {
67 System.out.println("For Linux only");
68 return;
69 }
70 UnixCommands.ensureCommandsAvailable("cat");
71
72 for (int i = 0; i < N; i++)
73 go(i);
74 }
75
76 /**
77 * Handle IO. Thread is started in constructor.
78 */
79 static class IO extends Thread {
80
81 private InputStream in;
82 private OutputStream out;
83
84 IO(String name, InputStream in, OutputStream out)
85 {
86 this.in = in;
87 this.out = out;
88 setName(name);
89 start();
90 }
91
92 public void run() {
93 try {
94 byte[] buf = new byte[8192];
95 int n;
96 while ((n = in.read(buf)) != -1) {
97 out.write(buf, 0, n);
98 out.flush();
99 }
100 /*
101 while ((c = in.read()) != -1) {
102 out.write(c);
103 if (c == '\n')
104 out.flush();
105 }
106 out.flush();
107 */
108 } catch (IOException e) {
109 e.printStackTrace();
110 } finally {
111 if (!System.out.equals(out) && !System.err.equals(out)) {
112 // Note: in order to get an exec'd java process to
113 // see EOF on input, it is necessary to close stdin
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