comparison src/org/tmatesoft/hg/internal/ProcessExecHelper.java @ 413:7f27122011c3

Support and respect for symbolic links and executable flag, with /bin/ls backed implementation to discover these
author Artem Tikhomirov <tikhomirov.artem@gmail.com>
date Wed, 21 Mar 2012 20:40:28 +0100
parents
children 9c9c442b5f2e
comparison
equal deleted inserted replaced
406:d56ea1a2537a 413:7f27122011c3
1 /*
2 * Copyright (c) 2012 TMate Software Ltd
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; version 2 of the License.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 * For information on how to redistribute this software under
14 * the terms of a license other than GNU General Public License
15 * contact TMate Software at support@hg4j.com
16 */
17 package org.tmatesoft.hg.internal;
18
19 import java.io.File;
20 import java.io.IOException;
21 import java.io.InputStreamReader;
22 import java.nio.CharBuffer;
23 import java.util.Arrays;
24 import java.util.LinkedList;
25 import java.util.List;
26
27 /**
28 * Utility to run shell commands. Not thread-safe.
29 * Beware of memory overcommitment issue on Linux - suprocess get allocated virtual memory of parent process size
30 * @see http://developers.sun.com/solaris/articles/subprocess/subprocess.html
31 *
32 * @author Artem Tikhomirov
33 * @author Tmate Software Ltd.
34 */
35 public class ProcessExecHelper {
36 private File dir;
37 private int exitValue;
38 private ProcessBuilder pb;
39
40 public ProcessExecHelper() {
41 }
42
43 protected List<String> prepareCommand(List<String> cmd) {
44 return cmd;
45 }
46
47 public CharSequence exec(String... command) throws IOException, InterruptedException {
48 return exec(Arrays.asList(command));
49 }
50
51 public CharSequence exec(List<String> command) throws IOException, InterruptedException {
52 List<String> cmd = prepareCommand(command);
53 if (pb == null) {
54 pb = new ProcessBuilder(cmd).directory(dir).redirectErrorStream(true);
55 } else {
56 pb.command(cmd); // dir and redirect are set
57 }
58 Process p = pb.start();
59 InputStreamReader stdOut = new InputStreamReader(p.getInputStream());
60 LinkedList<CharBuffer> l = new LinkedList<CharBuffer>();
61 int r = -1;
62 CharBuffer b = null;
63 do {
64 if (b == null || b.remaining() < b.capacity() / 3) {
65 b = CharBuffer.allocate(512);
66 l.add(b);
67 }
68 r = stdOut.read(b);
69 } while (r != -1);
70 int total = 0;
71 for (CharBuffer cb : l) {
72 total += cb.position();
73 cb.flip();
74 }
75 CharBuffer res = CharBuffer.allocate(total);
76 for (CharBuffer cb : l) {
77 res.put(cb);
78 }
79 res.flip();
80 p.waitFor();
81 exitValue = p.exitValue();
82 return res;
83 }
84
85 public int exitValue() {
86 return exitValue;
87 }
88
89 public ProcessExecHelper cwd(File wd) {
90 dir = wd;
91 if (pb != null) {
92 pb.directory(dir);
93 }
94 return this;
95 }
96 }