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/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
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package org.apache.sshd.common.util;

import java.io.File;
import java.nio.file.FileSystem;
import java.util.ArrayList;
import java.util.List;
import java.util.Objects;
import java.util.StringTokenizer;

/**
 * 

* This is a utility class used by selectors and DirectoryScanner. The functionality more properly belongs just to * selectors, but unfortunately DirectoryScanner exposed these as protected methods. Thus we have to support any * subclasses of DirectoryScanner that may access these methods. *

*

* This is a Singleton. *

* * @author Arnout J. Kuiper [email protected] * @author Magesh Umasankar * @author Bruce Atherton * @version $Id$ * @since 1.5 */ public final class SelectorUtils { public static final String PATTERN_HANDLER_PREFIX = "["; public static final String PATTERN_HANDLER_SUFFIX = "]"; public static final String REGEX_HANDLER_PREFIX = "%regex" + PATTERN_HANDLER_PREFIX; public static final String ANT_HANDLER_PREFIX = "%ant" + PATTERN_HANDLER_PREFIX; /** * Private Constructor */ private SelectorUtils() { throw new UnsupportedOperationException("No instance allowed"); } /** *

* Tests whether or not a given path matches the start of a given pattern up to the first "**". *

* *

* This is not a general purpose test and should only be used if you can live with false positives. For example, * pattern=**\a and str=b will yield true. *

* * @param pattern The pattern to match against. Must not be {@code null}. * @param str The path to match, as a String. Must not be {@code null}. * @return whether or not a given path matches the start of a given pattern up to the first "**". */ public static boolean matchPatternStart(String pattern, String str) { return matchPatternStart(pattern, str, true); } /** *

* Tests whether or not a given path matches the start of a given pattern up to the first "**". *

* *

* This is not a general purpose test and should only be used if you can live with false positives. For example, * pattern=**\a and str=b will yield true. *

* * @param pattern The pattern to match against. Must not be {@code null}. * @param str The path to match, as a String. Must not be {@code null}. * @param isCaseSensitive Whether or not matching should be performed case sensitively. * @return whether or not a given path matches the start of a given pattern up to the first * "**". */ public static boolean matchPatternStart(String pattern, String str, boolean isCaseSensitive) { return matchPath(pattern, str, File.separator, isCaseSensitive); } public static boolean matchPatternStart( String pattern, String str, String separator, boolean isCaseSensitive) { if ((pattern.length() > (REGEX_HANDLER_PREFIX.length() + PATTERN_HANDLER_SUFFIX.length() + 1)) && pattern.startsWith(REGEX_HANDLER_PREFIX) && pattern.endsWith(PATTERN_HANDLER_SUFFIX)) { // FIXME: ICK! But we can't do partial matches for regex, so we have to reserve judgement until we have // a file to deal with, or we can definitely say this is an exclusion... return true; } else { if ((pattern.length() > (ANT_HANDLER_PREFIX.length() + PATTERN_HANDLER_SUFFIX.length() + 1)) && pattern.startsWith(ANT_HANDLER_PREFIX) && pattern.endsWith(PATTERN_HANDLER_SUFFIX)) { pattern = pattern.substring(ANT_HANDLER_PREFIX.length(), pattern.length() - PATTERN_HANDLER_SUFFIX.length()); } if (matchAntPathPatternStart(pattern, str, separator, isCaseSensitive)) { return true; } return matchAntPathPatternStart(pattern, str.replace('\\', '/'), "/", isCaseSensitive); } } public static boolean matchAntPathPatternStart( String pattern, String str, String separator, boolean isCaseSensitive) { // When str starts with a File.separator, pattern has to start with a // File.separator. // When pattern starts with a File.separator, str has to start with a // File.separator. if (str.startsWith(separator) != pattern.startsWith(separator)) { return false; } List patDirs = tokenizePath(pattern, separator); List strDirs = tokenizePath(str, separator); int patIdxStart = 0; int patIdxEnd = patDirs.size() - 1; int strIdxStart = 0; int strIdxEnd = strDirs.size() - 1; // up to first '**' while (patIdxStart <= patIdxEnd && strIdxStart <= strIdxEnd) { String patDir = patDirs.get(patIdxStart); if (patDir.equals("**")) { break; } if (!match(patDir, strDirs.get(strIdxStart), isCaseSensitive)) { return false; } patIdxStart++; strIdxStart++; } // CHECKSTYLE:OFF if (strIdxStart > strIdxEnd) { // String is exhausted return true; } else { return patIdxStart <= patIdxEnd; } // CHECKSTYLE:ON } /** * Tests whether or not a given path matches a given pattern. * * @param pattern The pattern to match against. Must not be {@code null}. * @param str The path to match, as a String. Must not be {@code null}. * @return true if the pattern matches against the string, or false otherwise. */ public static boolean matchPath(String pattern, String str) { return matchPath(pattern, str, true); } /** * Tests whether or not a given path matches a given pattern. * * @param pattern The pattern to match against. Must not be {@code null}. * @param str The path to match, as a String. Must not be {@code null}. * @param isCaseSensitive Whether or not matching should be performed case sensitively. * @return true if the pattern matches against the string, or false * otherwise. */ public static boolean matchPath( String pattern, String str, boolean isCaseSensitive) { return matchPath(pattern, str, File.separator, isCaseSensitive); } public static boolean matchPath( String pattern, String str, String separator, boolean isCaseSensitive) { if ((pattern.length() > (REGEX_HANDLER_PREFIX.length() + PATTERN_HANDLER_SUFFIX.length() + 1)) && pattern.startsWith(REGEX_HANDLER_PREFIX) && pattern.endsWith(PATTERN_HANDLER_SUFFIX)) { pattern = pattern.substring(REGEX_HANDLER_PREFIX.length(), pattern.length() - PATTERN_HANDLER_SUFFIX.length()); return str.matches(pattern); } else { if ((pattern.length() > (ANT_HANDLER_PREFIX.length() + PATTERN_HANDLER_SUFFIX.length() + 1)) && pattern.startsWith(ANT_HANDLER_PREFIX) && pattern.endsWith(PATTERN_HANDLER_SUFFIX)) { pattern = pattern.substring(ANT_HANDLER_PREFIX.length(), pattern.length() - PATTERN_HANDLER_SUFFIX.length()); } return matchAntPathPattern(pattern, str, separator, isCaseSensitive); } } public static boolean matchAntPathPattern( String pattern, String str, boolean isCaseSensitive) { return matchAntPathPattern(pattern, str, File.separator, isCaseSensitive); } public static boolean matchAntPathPattern( String pattern, String str, String separator, boolean isCaseSensitive) { // When str starts with a file separator, pattern has to start with a // file separator. // When pattern starts with a file separator, str has to start with a // file separator. if (str.startsWith(separator) != pattern.startsWith(separator)) { return false; } List patDirs = tokenizePath(pattern, separator); List strDirs = tokenizePath(str, separator); int patIdxStart = 0; int patIdxEnd = patDirs.size() - 1; int strIdxStart = 0; int strIdxEnd = strDirs.size() - 1; // up to first '**' while (patIdxStart <= patIdxEnd && strIdxStart <= strIdxEnd) { String patDir = patDirs.get(patIdxStart); if (patDir.equals("**")) { break; } String subDir = strDirs.get(strIdxStart); if (!match(patDir, subDir, isCaseSensitive)) { patDirs = null; strDirs = null; return false; } patIdxStart++; strIdxStart++; } if (strIdxStart > strIdxEnd) { // String is exhausted for (int i = patIdxStart; i <= patIdxEnd; i++) { String subPat = patDirs.get(i); if (!subPat.equals("**")) { patDirs = null; strDirs = null; return false; } } return true; } else { if (patIdxStart > patIdxEnd) { // String not exhausted, but pattern is. Failure. patDirs = null; strDirs = null; return false; } } // up to last '**' while (patIdxStart <= patIdxEnd && strIdxStart <= strIdxEnd) { String patDir = patDirs.get(patIdxEnd); if (patDir.equals("**")) { break; } String subDir = strDirs.get(strIdxEnd); if (!match(patDir, subDir, isCaseSensitive)) { patDirs = null; strDirs = null; return false; } patIdxEnd--; strIdxEnd--; } if (strIdxStart > strIdxEnd) { // String is exhausted for (int i = patIdxStart; i <= patIdxEnd; i++) { String subPat = patDirs.get(i); if (!subPat.equals("**")) { patDirs = null; strDirs = null; return false; } } return true; } while (patIdxStart != patIdxEnd && strIdxStart <= strIdxEnd) { int patIdxTmp = -1; for (int i = patIdxStart + 1; i <= patIdxEnd; i++) { String subPat = patDirs.get(i); if (subPat.equals("**")) { patIdxTmp = i; break; } } if (patIdxTmp == patIdxStart + 1) { // '**/**' situation, so skip one patIdxStart++; continue; } // Find the pattern between padIdxStart & padIdxTmp in str between // strIdxStart & strIdxEnd int patLength = patIdxTmp - patIdxStart - 1; int strLength = strIdxEnd - strIdxStart + 1; int foundIdx = -1; strLoop: for (int i = 0; i <= strLength - patLength; i++) { for (int j = 0; j < patLength; j++) { String subPat = patDirs.get(patIdxStart + j + 1); String subStr = strDirs.get(strIdxStart + i + j); if (!match(subPat, subStr, isCaseSensitive)) { continue strLoop; } } foundIdx = strIdxStart + i; break; } if (foundIdx == -1) { patDirs = null; strDirs = null; return false; } patIdxStart = patIdxTmp; strIdxStart = foundIdx + patLength; } for (int i = patIdxStart; i <= patIdxEnd; i++) { String subPat = patDirs.get(i); if (!subPat.equals("**")) { patDirs = null; strDirs = null; return false; } } return true; } /** * Tests whether or not a string matches against a pattern. The pattern may contain two special characters:
* '*' means zero or more characters
* '?' means one and only one character * * @param pattern The pattern to match against. Must not be {@code null}. * @param str The string which must be matched against the pattern. Must not be {@code null}. * @return true if the string matches against the pattern, or false otherwise. */ public static boolean match(String pattern, String str) { return match(pattern, str, true); } /** * Tests whether or not a string matches against a pattern. The pattern may contain two special characters:
* '*' means zero or more characters
* '?' means one and only one character * * @param pattern The pattern to match against. Must not be {@code null}. * @param str The string which must be matched against the pattern. Must not be {@code null}. * @param isCaseSensitive Whether or not matching should be performed case sensitively. * @return true if the string matches against the pattern, or false * otherwise. */ @SuppressWarnings("PMD.AssignmentInOperand") public static boolean match(String pattern, String str, boolean isCaseSensitive) { char[] patArr = pattern.toCharArray(); char[] strArr = str.toCharArray(); int patIdxStart = 0; int patIdxEnd = patArr.length - 1; int strIdxStart = 0; int strIdxEnd = strArr.length - 1; char ch; boolean containsStar = false; for (char aPatArr : patArr) { if (aPatArr == '*') { containsStar = true; break; } } if (!containsStar) { // No '*'s, so we make a shortcut if (patIdxEnd != strIdxEnd) { return false; // Pattern and string do not have the same size } for (int i = 0; i <= patIdxEnd; i++) { ch = patArr[i]; if ((ch != '?') && (!equals(ch, strArr[i], isCaseSensitive))) { return false; // Character mismatch } } return true; // String matches against pattern } if (patIdxEnd == 0) { return true; // Pattern contains only '*', which matches anything } // Process characters before first star // CHECKSTYLE:OFF while (((ch = patArr[patIdxStart]) != '*') && (strIdxStart <= strIdxEnd)) { if ((ch != '?') && (!equals(ch, strArr[strIdxStart], isCaseSensitive))) { return false; // Character mismatch } patIdxStart++; strIdxStart++; } // CHECKSTYLE:ON if (strIdxStart > strIdxEnd) { // All characters in the string are used. Check if only '*'s are // left in the pattern. If so, we succeeded. Otherwise failure. for (int i = patIdxStart; i <= patIdxEnd; i++) { if (patArr[i] != '*') { return false; } } return true; } // Process characters after last star // CHECKSTYLE:OFF while (((ch = patArr[patIdxEnd]) != '*') && (strIdxStart <= strIdxEnd)) { if ((ch != '?') && (!equals(ch, strArr[strIdxEnd], isCaseSensitive))) { return false; // Character mismatch } patIdxEnd--; strIdxEnd--; } // CHECKSTYLE:ON if (strIdxStart > strIdxEnd) { // All characters in the string are used. Check if only '*'s are // left in the pattern. If so, we succeeded. Otherwise failure. for (int i = patIdxStart; i <= patIdxEnd; i++) { if (patArr[i] != '*') { return false; } } return true; } // process pattern between stars. padIdxStart and patIdxEnd point always to a '*'. while ((patIdxStart != patIdxEnd) && (strIdxStart <= strIdxEnd)) { int patIdxTmp = -1; for (int i = patIdxStart + 1; i <= patIdxEnd; i++) { if (patArr[i] == '*') { patIdxTmp = i; break; } } if (patIdxTmp == patIdxStart + 1) { // Two stars next to each other, skip the first one. patIdxStart++; continue; } // Find the pattern between padIdxStart & padIdxTmp in str between // strIdxStart & strIdxEnd int patLength = patIdxTmp - patIdxStart - 1; int strLength = strIdxEnd - strIdxStart + 1; int foundIdx = -1; strLoop: for (int i = 0; i <= strLength - patLength; i++) { for (int j = 0; j < patLength; j++) { ch = patArr[patIdxStart + j + 1]; if (ch != '?' && !equals(ch, strArr[strIdxStart + i + j], isCaseSensitive)) { continue strLoop; } } foundIdx = strIdxStart + i; break; } if (foundIdx == -1) { return false; } patIdxStart = patIdxTmp; strIdxStart = foundIdx + patLength; } // All characters in the string are used. Check if only '*'s are left // in the pattern. If so, we succeeded. Otherwise failure. for (int i = patIdxStart; i <= patIdxEnd; i++) { if (patArr[i] != '*') { return false; } } return true; } /** * Tests whether two characters are equal. * * @param c1 1st character * @param c2 2nd character * @param isCaseSensitive Whether to compare case sensitive * @return {@code true} if equal characters */ public static boolean equals(char c1, char c2, boolean isCaseSensitive) { if (c1 == c2) { return true; } if (!isCaseSensitive) { // NOTE: Try both upper case and lower case as done by String.equalsIgnoreCase() if (Character.toUpperCase(c1) == Character.toUpperCase(c2) || Character.toLowerCase(c1) == Character.toLowerCase(c2)) { return true; } } return false; } /** * Breaks a path up into a Vector of path elements, tokenizing on File.separator. * * @param path Path to tokenize. Must not be {@code null}. * @return a List of path elements from the tokenized path */ public static List tokenizePath(String path) { return tokenizePath(path, File.separator); } public static List tokenizePath(String path, String separator) { List ret = new ArrayList<>(); StringTokenizer st = new StringTokenizer(path, separator); while (st.hasMoreTokens()) { ret.add(st.nextToken()); } return ret; } /** * /** Converts a path to one matching the target file system by applying the "slashification" rules, * converting it to a local path and then translating its separator to the target file system one (if different than * local one) * * @param path The input path * @param pathSeparator The separator used to build the input path * @param fs The target {@link FileSystem} - may not be {@code null} * @return The transformed path * @see #translateToLocalFileSystemPath(String, char, String) */ public static String translateToLocalFileSystemPath(String path, char pathSeparator, FileSystem fs) { return translateToLocalFileSystemPath(path, pathSeparator, Objects.requireNonNull(fs, "No target file system").getSeparator()); } /** * Converts a path to one matching the target file system by applying the "slashification" rules, * converting it to a local path and then translating its separator to the target file system one (if different than * local one) * * @param path The input path * @param pathSeparator The separator used to build the input path * @param fsSeparator The target file system separator * @return The transformed path * @see #applySlashifyRules(String, char) * @see #translateToLocalPath(String) * @see #translateToFileSystemPath(String, String, String) */ public static String translateToLocalFileSystemPath(String path, char pathSeparator, String fsSeparator) { // In case double slashes and other patterns are used String slashified = applySlashifyRules(path, pathSeparator); // In case we are running on Windows String localPath = translateToLocalPath(slashified); return translateToFileSystemPath(localPath, File.separator, fsSeparator); } /** * Applies the "slashification" rules as specified in * Single Unix * Specification version 3, section 3.266 and * section 4.11 - * Pathname resolution * * @param path The original path - ignored if {@code null}/empty or does not contain any slashes * @param sepChar The "slash" character * @return The effective path - may be same as input if no changes required */ public static String applySlashifyRules(String path, char sepChar) { if (GenericUtils.isEmpty(path)) { return path; } int curPos = path.indexOf(sepChar); if (curPos < 0) { return path; // no slashes to handle } int lastPos = 0; StringBuilder sb = null; while (curPos < path.length()) { curPos++; // skip the 1st '/' /* * As per Single Unix Specification version 3, section 3.266: * * Multiple successive slashes are considered to be the same as one slash */ int nextPos = curPos; while ((nextPos < path.length()) && (path.charAt(nextPos) == sepChar)) { nextPos++; } /* * At this stage, nextPos is the first non-slash character after a possibly 'seqLen' sequence of consecutive * slashes. */ int seqLen = nextPos - curPos; if (seqLen > 0) { if (sb == null) { sb = new StringBuilder(path.length() - seqLen); } if (lastPos < curPos) { String clrText = path.substring(lastPos, curPos); sb.append(clrText); } lastPos = nextPos; } if (nextPos >= path.length()) { break; // no more data } curPos = path.indexOf(sepChar, nextPos); if (curPos < nextPos) { break; // no more slashes } } // check if any leftovers for the modified path if (sb != null) { if (lastPos < path.length()) { String clrText = path.substring(lastPos); sb.append(clrText); } path = sb.toString(); } /* * At this point we know for sure that 'path' contains only SINGLE slashes. According to section 4.11 - Pathname * resolution * * A pathname that contains at least one non-slash character and that ends with one or more trailing slashes * shall be resolved as if a single dot character ( '.' ) were appended to the pathname. */ if ((path.length() > 1) && (path.charAt(path.length() - 1) == sepChar)) { return path + "."; } else { return path; } } /** * Converts a possibly '/' separated path to a local path. Note: takes special care of Windows drive paths - * e.g., {@code C:} by converting them to "C:\" * * @param path The original path - ignored if {@code null}/empty * @return The local path */ public static String translateToLocalPath(String path) { if (GenericUtils.isEmpty(path) || (File.separatorChar == '/')) { return path; } // This code is reached if we are running on Windows String localPath = path.replace('/', File.separatorChar); // check if '/c:' prefix if ((localPath.charAt(0) == File.separatorChar) && isWindowsDriveSpecified(localPath, 1, localPath.length() - 1)) { localPath = localPath.substring(1); } if (!isWindowsDriveSpecified(localPath)) { return localPath; // assume a relative path } /* * Here we know that we have at least a "C:" string - make sure it is followed by the local file separator. * Note: if all we have is just the drive, we will create a "C:\" path since this is the preferred Windows way * to refer to root drives in the file system */ if (localPath.length() == 2) { return localPath + File.separator; // all we have is "C:" } else if (localPath.charAt(2) != File.separatorChar) { // be nice and add the missing file separator - C:foo => C:\foo return localPath.substring(0, 2) + File.separator + localPath.substring(2); } else { return localPath; } } public static boolean isWindowsDriveSpecified(CharSequence cs) { return isWindowsDriveSpecified(cs, 0, GenericUtils.length(cs)); } public static boolean isWindowsDriveSpecified(CharSequence cs, int offset, int len) { if ((len < 2) || (cs.charAt(offset + 1) != ':')) { return false; } char drive = cs.charAt(offset); return ((drive >= 'a') && (drive <= 'z')) || ((drive >= 'A') && (drive <= 'Z')); } /** * Converts a path containing a specific separator to one using the specified file-system one * * @param path The input path - ignored if {@code null}/empty * @param pathSeparator The separator used to build the input path - may not be {@code null}/empty * @param fs The target {@link FileSystem} - may not be {@code null} * @return The path where the separator used to build it is replaced by the file-system one (if * different) * @see FileSystem#getSeparator() * @see #translateToFileSystemPath(String, String, String) */ public static String translateToFileSystemPath(String path, String pathSeparator, FileSystem fs) { return translateToFileSystemPath(path, pathSeparator, Objects.requireNonNull(fs, "No target file system").getSeparator()); } /** * Converts a path containing a specific separator to one using the specified file-system one * * @param path The input path - ignored if {@code null}/empty * @param pathSeparator The separator used to build the input path - may not be {@code null}/empty * @param fsSeparator The target file system separator - may not be {@code null}/empty * @return The path where the separator used to build it is replaced by the file-system one * (if different) * @throws IllegalArgumentException if path or file-system separator are {@code null}/empty or if the separators are * different and the path contains the target file-system separator as it would * create an ambiguity */ public static String translateToFileSystemPath(String path, String pathSeparator, String fsSeparator) { ValidateUtils.checkNotNullAndNotEmpty(pathSeparator, "Missing path separator"); ValidateUtils.checkNotNullAndNotEmpty(fsSeparator, "Missing file-system separator"); if (GenericUtils.isEmpty(path) || Objects.equals(pathSeparator, fsSeparator)) { return path; } // make sure path does not contain the target separator if (path.contains(fsSeparator)) { ValidateUtils.throwIllegalArgumentException( "File system replacement may yield ambiguous result for %s with separator=%s", path, fsSeparator); } // check most likely case if ((pathSeparator.length() == 1) && (fsSeparator.length() == 1)) { return path.replace(pathSeparator.charAt(0), fsSeparator.charAt(0)); } else { return path.replace(pathSeparator, fsSeparator); } } /** * Creates a single path by concatenating 2 parts and taking care not to create FS separator duplication in the * process * * @param p1 prefix part - ignored if {@code null}/empty * @param p2 suffix part - ignored if {@code null}/empty * @param fsSeparator The expected file-system separator * @return Concatenation result */ public static String concatPaths(String p1, String p2, char fsSeparator) { if (GenericUtils.isEmpty(p1)) { return p2; } else if (GenericUtils.isEmpty(p2)) { return p1; } else if (p1.charAt(p1.length() - 1) == fsSeparator) { if (p2.charAt(0) == fsSeparator) { return (p2.length() == 1) ? p1 : p1 + p2.substring(1); // a/b/c/ + /d/e/f } else { return p1 + p2; // a/b/c/ + d/e/f } } else if (p2.charAt(0) == fsSeparator) { return (p2.length() == 1) ? p1 : p1 + p2; // /a/b/c + /d/e/f } else { return p1 + Character.toString(fsSeparator) + p2; // /a/b/c + d/e/f } } /** * "Flattens" a string by removing all whitespace (space, tab, line-feed, carriage return, and form-feed). This uses * StringTokenizer and the default set of tokens as documented in the single argument constructor. * * @param input a String to remove all whitespace. * @return a String that has had all whitespace removed. */ public static String removeWhitespace(String input) { StringBuilder result = new StringBuilder(); if (input != null) { StringTokenizer st = new StringTokenizer(input); while (st.hasMoreTokens()) { result.append(st.nextToken()); } } return result.toString(); } }




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