russell@unturf.com
0a580b313d
Authors: russell@unturf.com · brackishbert@gmail.com · foxhop.net · TimeHexOn.com Patches, unit tests, benchmarks, whitepaper, and outreach briefs. Public domain — no copyright claimed. Use freely.
62 lines
2.2 KiB
Java
62 lines
2.2 KiB
Java
/*
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* Copyright (c) 2026, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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* or visit www.oracle.com if you need additional information or have any
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* questions.
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*/
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/**
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* Accessor for Native calls to get information about File Descriptors.
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* If it's a pipe and its Inode number.
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*/
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public class LinuxFDInfo {
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static {
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System.loadLibrary("LinuxFDInfo");
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}
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// Maximum file descriptor to probe for being a pipe,
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private final static int MAX_FD = 100;
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// A simple main to print the pipes in this process and their Inode value
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public static void main() {
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for (int fd = 0; fd < MAX_FD; fd++) {
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long inode = getPipeInodeNum(fd);
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if (inode != 0) {
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System.out.printf("fd: %d, inode: 0x%08x\n", fd, inode);
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}
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}
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}
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// Parse the output from main into a long array of the fd, and Inode.
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public static FdAndInode parseFdAndInode(String s) {
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String[] args = s.split(",");
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return new FdAndInode(Integer.parseUnsignedInt(args[0].split(":")[1].trim()),
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Long.parseUnsignedLong(args[1].split(":")[1].trim().substring(2), 16));
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}
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/**
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* Return the inode number for the FD, if it is a pipe.
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* @param fd file descriptor
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* @return the Inode number.
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*/
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public static native long getPipeInodeNum(int fd);
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public record FdAndInode(int fd, long inode) {}
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}
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