mirror of https://github.com/termux/termux-app
146 lines
5.7 KiB
Java
146 lines
5.7 KiB
Java
/*
|
|
* Copyright (c) 2007, 2011, Oracle and/or its affiliates. All rights reserved.
|
|
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
|
|
*
|
|
* This code is free software; you can redistribute it and/or modify it
|
|
* under the terms of the GNU General Public License version 2 only, as
|
|
* published by the Free Software Foundation. Oracle designates this
|
|
* particular file as subject to the "Classpath" exception as provided
|
|
* by Oracle in the LICENSE file that accompanied this code.
|
|
*
|
|
* This code is distributed in the hope that it will be useful, but WITHOUT
|
|
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
|
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
|
* version 2 for more details (a copy is included in the LICENSE file that
|
|
* accompanied this code).
|
|
*
|
|
* You should have received a copy of the GNU General Public License version
|
|
* 2 along with this work; if not, write to the Free Software Foundation,
|
|
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
|
|
*
|
|
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
|
|
* or visit www.oracle.com if you need additional information or have any
|
|
* questions.
|
|
*/
|
|
|
|
package com.termux.shared.file.filesystem;
|
|
|
|
import static com.termux.shared.file.filesystem.FilePermission.*;
|
|
|
|
import java.util.*;
|
|
|
|
/**
|
|
* This class consists exclusively of static methods that operate on sets of
|
|
* {@link FilePermission} objects.
|
|
*
|
|
* https://cs.android.com/android/platform/superproject/+/android-11.0.0_r3:libcore/ojluni/src/main/java/java/nio/file/attribute/PosixFilePermissions.java
|
|
*
|
|
* @since 1.7
|
|
*/
|
|
|
|
public final class FilePermissions {
|
|
private FilePermissions() { }
|
|
|
|
// Write string representation of permission bits to {@code sb}.
|
|
private static void writeBits(StringBuilder sb, boolean r, boolean w, boolean x) {
|
|
if (r) {
|
|
sb.append('r');
|
|
} else {
|
|
sb.append('-');
|
|
}
|
|
if (w) {
|
|
sb.append('w');
|
|
} else {
|
|
sb.append('-');
|
|
}
|
|
if (x) {
|
|
sb.append('x');
|
|
} else {
|
|
sb.append('-');
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Returns the {@code String} representation of a set of permissions. It
|
|
* is guaranteed that the returned {@code String} can be parsed by the
|
|
* {@link #fromString} method.
|
|
*
|
|
* <p> If the set contains {@code null} or elements that are not of type
|
|
* {@code FilePermission} then these elements are ignored.
|
|
*
|
|
* @param perms
|
|
* the set of permissions
|
|
*
|
|
* @return the string representation of the permission set
|
|
*/
|
|
public static String toString(Set<FilePermission> perms) {
|
|
StringBuilder sb = new StringBuilder(9);
|
|
writeBits(sb, perms.contains(OWNER_READ), perms.contains(OWNER_WRITE),
|
|
perms.contains(OWNER_EXECUTE));
|
|
writeBits(sb, perms.contains(GROUP_READ), perms.contains(GROUP_WRITE),
|
|
perms.contains(GROUP_EXECUTE));
|
|
writeBits(sb, perms.contains(OTHERS_READ), perms.contains(OTHERS_WRITE),
|
|
perms.contains(OTHERS_EXECUTE));
|
|
return sb.toString();
|
|
}
|
|
|
|
private static boolean isSet(char c, char setValue) {
|
|
if (c == setValue)
|
|
return true;
|
|
if (c == '-')
|
|
return false;
|
|
throw new IllegalArgumentException("Invalid mode");
|
|
}
|
|
private static boolean isR(char c) { return isSet(c, 'r'); }
|
|
private static boolean isW(char c) { return isSet(c, 'w'); }
|
|
private static boolean isX(char c) { return isSet(c, 'x'); }
|
|
|
|
/**
|
|
* Returns the set of permissions corresponding to a given {@code String}
|
|
* representation.
|
|
*
|
|
* <p> The {@code perms} parameter is a {@code String} representing the
|
|
* permissions. It has 9 characters that are interpreted as three sets of
|
|
* three. The first set refers to the owner's permissions; the next to the
|
|
* group permissions and the last to others. Within each set, the first
|
|
* character is {@code 'r'} to indicate permission to read, the second
|
|
* character is {@code 'w'} to indicate permission to write, and the third
|
|
* character is {@code 'x'} for execute permission. Where a permission is
|
|
* not set then the corresponding character is set to {@code '-'}.
|
|
*
|
|
* <p> <b>Usage Example:</b>
|
|
* Suppose we require the set of permissions that indicate the owner has read,
|
|
* write, and execute permissions, the group has read and execute permissions
|
|
* and others have none.
|
|
* <pre>
|
|
* Set<FilePermission> perms = FilePermissions.fromString("rwxr-x---");
|
|
* </pre>
|
|
*
|
|
* @param perms
|
|
* string representing a set of permissions
|
|
*
|
|
* @return the resulting set of permissions
|
|
*
|
|
* @throws IllegalArgumentException
|
|
* if the string cannot be converted to a set of permissions
|
|
*
|
|
* @see #toString(Set)
|
|
*/
|
|
public static Set<FilePermission> fromString(String perms) {
|
|
if (perms.length() != 9)
|
|
throw new IllegalArgumentException("Invalid mode");
|
|
Set<FilePermission> result = EnumSet.noneOf(FilePermission.class);
|
|
if (isR(perms.charAt(0))) result.add(OWNER_READ);
|
|
if (isW(perms.charAt(1))) result.add(OWNER_WRITE);
|
|
if (isX(perms.charAt(2))) result.add(OWNER_EXECUTE);
|
|
if (isR(perms.charAt(3))) result.add(GROUP_READ);
|
|
if (isW(perms.charAt(4))) result.add(GROUP_WRITE);
|
|
if (isX(perms.charAt(5))) result.add(GROUP_EXECUTE);
|
|
if (isR(perms.charAt(6))) result.add(OTHERS_READ);
|
|
if (isW(perms.charAt(7))) result.add(OTHERS_WRITE);
|
|
if (isX(perms.charAt(8))) result.add(OTHERS_EXECUTE);
|
|
return result;
|
|
}
|
|
|
|
}
|