2 * Copyright (c) 2015 Cisco Systems, Inc. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.yangtools.yang.parser.rfc7950.repo;
10 import com.google.common.annotations.VisibleForTesting;
11 import com.google.common.base.CharMatcher;
12 import java.util.Collections;
13 import java.util.List;
14 import java.util.regex.Pattern;
15 import org.antlr.v4.runtime.tree.TerminalNode;
16 import org.opendaylight.yangtools.antlrv4.code.gen.YangStatementParser.ArgumentContext;
17 import org.opendaylight.yangtools.yang.common.YangVersion;
18 import org.opendaylight.yangtools.yang.parser.spi.source.SourceException;
19 import org.opendaylight.yangtools.yang.parser.spi.source.StatementSourceReference;
21 final class ArgumentContextUtils {
22 private static final CharMatcher WHITESPACE_MATCHER = CharMatcher.whitespace();
23 private static final CharMatcher ANYQUOTE_MATCHER = CharMatcher.anyOf("'\"");
24 private static final Pattern ESCAPED_DQUOT = Pattern.compile("\\\"", Pattern.LITERAL);
25 private static final Pattern ESCAPED_BACKSLASH = Pattern.compile("\\\\", Pattern.LITERAL);
26 private static final Pattern ESCAPED_LF = Pattern.compile("\\n", Pattern.LITERAL);
27 private static final Pattern ESCAPED_TAB = Pattern.compile("\\t", Pattern.LITERAL);
29 private ArgumentContextUtils() {
30 throw new UnsupportedOperationException();
33 static String stringFromStringContext(final ArgumentContext context, final StatementSourceReference ref) {
34 return stringFromStringContext(context, YangVersion.VERSION_1, ref);
37 static String stringFromStringContext(final ArgumentContext context, final YangVersion yangVersion,
38 final StatementSourceReference ref) {
39 final StringBuilder sb = new StringBuilder();
40 List<TerminalNode> strings = context.STRING();
41 if (strings.isEmpty()) {
42 strings = Collections.singletonList(context.IDENTIFIER());
44 for (final TerminalNode stringNode : strings) {
45 final String str = stringNode.getText();
46 final char firstChar = str.charAt(0);
47 final char lastChar = str.charAt(str.length() - 1);
48 if (firstChar == '"' && lastChar == '"') {
49 final String innerStr = str.substring(1, str.length() - 1);
51 * Unescape escaped double quotes, tabs, new line and backslash
52 * in the inner string and trim the result.
54 checkDoubleQuotedString(innerStr, yangVersion, ref);
56 sb.append(ESCAPED_TAB.matcher(
58 ESCAPED_BACKSLASH.matcher(
59 ESCAPED_DQUOT.matcher(
60 trimWhitespace(innerStr, stringNode.getSymbol().getCharPositionInLine()))
65 } else if (firstChar == '\'' && lastChar == '\'') {
67 * According to RFC6020 a single quote character cannot occur in
68 * a single-quoted string, even when preceded by a backslash.
70 sb.append(str.substring(1, str.length() - 1));
72 checkUnquotedString(str, yangVersion, ref);
79 private static void checkUnquotedString(final String str, final YangVersion yangVersion,
80 final StatementSourceReference ref) {
81 if (yangVersion == YangVersion.VERSION_1_1) {
82 SourceException.throwIf(ANYQUOTE_MATCHER.matchesAnyOf(str), ref,
83 "YANG 1.1: unquoted string (%s) contains illegal characters", str);
87 private static void checkDoubleQuotedString(final String str, final YangVersion yangVersion,
88 final StatementSourceReference ref) {
89 if (yangVersion == YangVersion.VERSION_1_1) {
90 for (int i = 0; i < str.length() - 1; i++) {
91 if (str.charAt(i) == '\\') {
92 switch (str.charAt(i + 1)) {
100 throw new SourceException(ref, "YANG 1.1: illegal double quoted string (%s). In double "
101 + "quoted string the backslash must be followed by one of the following character "
102 + "[n,t,\",\\], but was '%s'.", str, str.charAt(i + 1));
110 static String trimWhitespace(final String str, final int dquot) {
111 int brk = str.indexOf('\n');
113 // No need to trim whitespace
117 // Okay, we may need to do some trimming, set up a builder and append the first segment
118 final int length = str.length();
119 final StringBuilder sb = new StringBuilder(length);
121 // Append first segment, which needs only tail-trimming
122 sb.append(str, 0, trimTrailing(str, 0, brk)).append('\n');
124 // With that out of the way, setup our iteration state. The string segment we are looking at is
125 // str.substring(start, end), which is guaranteed not to include any line breaks, i.e. end <= brk unless we are
126 // at the last segment.
128 brk = str.indexOf('\n', start);
130 // Loop over inner strings
132 final int end = brk != -1 ? brk : length;
133 trimLeadingAndAppend(sb, dquot, str, start, trimTrailing(str, start, end)).append('\n');
135 brk = str.indexOf('\n', start);
138 return trimLeadingAndAppend(sb, dquot, str, start, length).toString();
141 private static StringBuilder trimLeadingAndAppend(final StringBuilder sb, final int dquot, final String str,
142 final int start, final int end) {
146 while (pos <= dquot) {
148 // We ran out of data, nothing to append
152 final char ch = str.charAt(offset);
154 // tabs are to be treated as 8 spaces
156 } else if (WHITESPACE_MATCHER.matches(ch)) {
165 // We have expanded beyond double quotes, push equivalent spaces
166 while (pos - 1 > dquot) {
171 return sb.append(str, offset, end);
174 private static int trimTrailing(final String str, final int start, final int end) {
176 while (ret > start) {
177 final int prev = ret - 1;
178 if (!WHITESPACE_MATCHER.matches(str.charAt(prev))) {