/*
 * Copyright (C) 2008, 2019 Google Inc. and others
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Distribution License v. 1.0 which is available at
 * https://www.eclipse.org/org/documents/edl-v10.php.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

package org.eclipse.jgit.util;

import static java.nio.charset.StandardCharsets.UTF_8;

import java.util.Arrays;

import org.eclipse.jgit.lib.Constants;

Utility functions related to quoted string handling.
/** * Utility functions related to quoted string handling. */
public abstract class QuotedString {
Quoting style that obeys the rules Git applies to file names
/** Quoting style that obeys the rules Git applies to file names */
public static final GitPathStyle GIT_PATH = new GitPathStyle(true);
Quoting style that obeys the rules Git applies to file names when core.quotePath = false.
Since:5.6
/** * Quoting style that obeys the rules Git applies to file names when * {@code core.quotePath = false}. * * @since 5.6 */
public static final QuotedString GIT_PATH_MINIMAL = new GitPathStyle(false);
Quoting style used by the Bourne shell.

Quotes are unconditionally inserted during quote(String). This protects shell meta-characters like $ or ~ from being recognized as special.

/** * Quoting style used by the Bourne shell. * <p> * Quotes are unconditionally inserted during {@link #quote(String)}. This * protects shell meta-characters like <code>$</code> or <code>~</code> from * being recognized as special. */
public static final BourneStyle BOURNE = new BourneStyle();
Bourne style, but permits ~user at the start of the string.
/** Bourne style, but permits <code>~user</code> at the start of the string. */
public static final BourneUserPathStyle BOURNE_USER_PATH = new BourneUserPathStyle();
Quote an input string by the quoting rules.

If the input string does not require any quoting, the same String reference is returned to the caller.

Otherwise a quoted string is returned, including the opening and closing quotation marks at the start and end of the string. If the style does not permit raw Unicode characters then the string will first be encoded in UTF-8, with unprintable sequences possibly escaped by the rules.

Params:
  • in – any non-null Unicode string.
Returns:a quoted string. See above for details.
/** * Quote an input string by the quoting rules. * <p> * If the input string does not require any quoting, the same String * reference is returned to the caller. * <p> * Otherwise a quoted string is returned, including the opening and closing * quotation marks at the start and end of the string. If the style does not * permit raw Unicode characters then the string will first be encoded in * UTF-8, with unprintable sequences possibly escaped by the rules. * * @param in * any non-null Unicode string. * @return a quoted string. See above for details. */
public abstract String quote(String in);
Clean a previously quoted input, decoding the result via UTF-8.

This method must match quote such that:

a.equals(dequote(quote(a)));
is true for any a.
Params:
  • in – a Unicode string to remove quoting from.
See Also:
Returns:the cleaned string.
/** * Clean a previously quoted input, decoding the result via UTF-8. * <p> * This method must match quote such that: * * <pre> * a.equals(dequote(quote(a))); * </pre> * * is true for any <code>a</code>. * * @param in * a Unicode string to remove quoting from. * @return the cleaned string. * @see #dequote(byte[], int, int) */
public String dequote(String in) { final byte[] b = Constants.encode(in); return dequote(b, 0, b.length); }
Decode a previously quoted input, scanning a UTF-8 encoded buffer.

This method must match quote such that:

a.equals(dequote(Constants.encode(quote(a))));
is true for any a.

This method removes any opening/closing quotation marks added by quote(String).

Params:
  • in – the input buffer to parse.
  • offset – first position within in to scan.
  • end – one position past in in to scan.
Returns:the cleaned string.
/** * Decode a previously quoted input, scanning a UTF-8 encoded buffer. * <p> * This method must match quote such that: * * <pre> * a.equals(dequote(Constants.encode(quote(a)))); * </pre> * * is true for any <code>a</code>. * <p> * This method removes any opening/closing quotation marks added by * {@link #quote(String)}. * * @param in * the input buffer to parse. * @param offset * first position within <code>in</code> to scan. * @param end * one position past in <code>in</code> to scan. * @return the cleaned string. */
public abstract String dequote(byte[] in, int offset, int end);
Quoting style used by the Bourne shell.

Quotes are unconditionally inserted during quote(String). This protects shell meta-characters like $ or ~ from being recognized as special.

/** * Quoting style used by the Bourne shell. * <p> * Quotes are unconditionally inserted during {@link #quote(String)}. This * protects shell meta-characters like <code>$</code> or <code>~</code> from * being recognized as special. */
public static class BourneStyle extends QuotedString { @Override public String quote(String in) { final StringBuilder r = new StringBuilder(); r.append('\''); int start = 0, i = 0; for (; i < in.length(); i++) { switch (in.charAt(i)) { case '\'': case '!': r.append(in, start, i); r.append('\''); r.append('\\'); r.append(in.charAt(i)); r.append('\''); start = i + 1; break; } } r.append(in, start, i); r.append('\''); return r.toString(); } @Override public String dequote(byte[] in, int ip, int ie) { boolean inquote = false; final byte[] r = new byte[ie - ip]; int rPtr = 0; while (ip < ie) { final byte b = in[ip++]; switch (b) { case '\'': inquote = !inquote; continue; case '\\': if (inquote || ip == ie) r[rPtr++] = b; // literal within a quote else r[rPtr++] = in[ip++]; continue; default: r[rPtr++] = b; continue; } } return RawParseUtils.decode(UTF_8, r, 0, rPtr); } }
Bourne style, but permits ~user at the start of the string.
/** Bourne style, but permits <code>~user</code> at the start of the string. */
public static class BourneUserPathStyle extends BourneStyle { @Override public String quote(String in) { if (in.matches("^~[A-Za-z0-9_-]+$")) { //$NON-NLS-1$ // If the string is just "~user" we can assume they // mean "~user/". // return in + "/"; //$NON-NLS-1$ } if (in.matches("^~[A-Za-z0-9_-]*/.*$")) { //$NON-NLS-1$ // If the string is of "~/path" or "~user/path" // we must not escape ~/ or ~user/ from the shell. // final int i = in.indexOf('/') + 1; if (i == in.length()) return in; return in.substring(0, i) + super.quote(in.substring(i)); } return super.quote(in); } }
Quoting style that obeys the rules Git applies to file names
/** Quoting style that obeys the rules Git applies to file names */
public static final class GitPathStyle extends QuotedString { private static final byte[] quote; static { quote = new byte[128]; Arrays.fill(quote, (byte) -1); for (int i = '0'; i <= '9'; i++) quote[i] = 0; for (int i = 'a'; i <= 'z'; i++) quote[i] = 0; for (int i = 'A'; i <= 'Z'; i++) quote[i] = 0; quote[' '] = 0; quote['$'] = 0; quote['%'] = 0; quote['&'] = 0; quote['*'] = 0; quote['+'] = 0; quote[','] = 0; quote['-'] = 0; quote['.'] = 0; quote['/'] = 0; quote[':'] = 0; quote[';'] = 0; quote['='] = 0; quote['?'] = 0; quote['@'] = 0; quote['_'] = 0; quote['^'] = 0; quote['|'] = 0; quote['~'] = 0; quote['\u0007'] = 'a'; quote['\b'] = 'b'; quote['\f'] = 'f'; quote['\n'] = 'n'; quote['\r'] = 'r'; quote['\t'] = 't'; quote['\u000B'] = 'v'; quote['\\'] = '\\'; quote['"'] = '"'; } private final boolean quoteHigh; @Override public String quote(String instr) { if (instr.isEmpty()) { return "\"\""; //$NON-NLS-1$ } boolean reuse = true; final byte[] in = Constants.encode(instr); final byte[] out = new byte[4 * in.length + 2]; int o = 0; out[o++] = '"'; for (byte element : in) { final int c = element & 0xff; if (c < quote.length) { final byte style = quote[c]; if (style == 0) { out[o++] = (byte) c; continue; } if (style > 0) { reuse = false; out[o++] = '\\'; out[o++] = style; continue; } } else if (!quoteHigh) { out[o++] = (byte) c; continue; } reuse = false; out[o++] = '\\'; out[o++] = (byte) (((c >> 6) & 03) + '0'); out[o++] = (byte) (((c >> 3) & 07) + '0'); out[o++] = (byte) (((c >> 0) & 07) + '0'); } if (reuse) { return instr; } out[o++] = '"'; return new String(out, 0, o, UTF_8); } @Override public String dequote(byte[] in, int inPtr, int inEnd) { if (2 <= inEnd - inPtr && in[inPtr] == '"' && in[inEnd - 1] == '"') return dq(in, inPtr + 1, inEnd - 1); return RawParseUtils.decode(UTF_8, in, inPtr, inEnd); } private static String dq(byte[] in, int inPtr, int inEnd) { final byte[] r = new byte[inEnd - inPtr]; int rPtr = 0; while (inPtr < inEnd) { final byte b = in[inPtr++]; if (b != '\\') { r[rPtr++] = b; continue; } if (inPtr == inEnd) { // Lone trailing backslash. Treat it as a literal. // r[rPtr++] = '\\'; break; } switch (in[inPtr++]) { case 'a': r[rPtr++] = 0x07 /* \a = BEL */; continue; case 'b': r[rPtr++] = '\b'; continue; case 'f': r[rPtr++] = '\f'; continue; case 'n': r[rPtr++] = '\n'; continue; case 'r': r[rPtr++] = '\r'; continue; case 't': r[rPtr++] = '\t'; continue; case 'v': r[rPtr++] = 0x0B/* \v = VT */; continue; case '\\': case '"': r[rPtr++] = in[inPtr - 1]; continue; case '0': case '1': case '2': case '3': { int cp = in[inPtr - 1] - '0'; for (int n = 1; n < 3 && inPtr < inEnd; n++) { final byte c = in[inPtr]; if ('0' <= c && c <= '7') { cp <<= 3; cp |= c - '0'; inPtr++; } else { break; } } r[rPtr++] = (byte) cp; continue; } default: // Any other code is taken literally. // r[rPtr++] = '\\'; r[rPtr++] = in[inPtr - 1]; continue; } } return RawParseUtils.decode(UTF_8, r, 0, rPtr); } private GitPathStyle(boolean doQuote) { quoteHigh = doQuote; } } }