From 7bc4883dfb2e83588a3575a256bf466b4a46c4f2 Mon Sep 17 00:00:00 2001
From: Adam Dickmeiss <adam@indexdata.dk>
Date: Fri, 10 Oct 2025 13:26:38 +0200
Subject: [PATCH 1/2] Retain escape sequences in lexer, fixes #5

\\ is preserved in Lexer, leaving it to later stages to decide
what masking is to be used.
---
 .../java/org/z3950/zing/cql/CQLGenerator.java    |  2 +-
 src/main/java/org/z3950/zing/cql/CQLLexer.java   | 16 ++++++----------
 .../java/org/z3950/zing/cql/CQLTermNode.java     |  2 +-
 src/test/resources/regression/06/03.xcql         |  2 +-
 src/test/resources/regression/06/06.xcql         |  2 +-
 src/test/resources/regression/12/01.xcql         |  2 +-
 6 files changed, 11 insertions(+), 15 deletions(-)

diff --git a/src/main/java/org/z3950/zing/cql/CQLGenerator.java b/src/main/java/org/z3950/zing/cql/CQLGenerator.java
index 2f21563..0b291a4 100644
--- a/src/main/java/org/z3950/zing/cql/CQLGenerator.java
+++ b/src/main/java/org/z3950/zing/cql/CQLGenerator.java
@@ -204,7 +204,7 @@ private String generate_base_relation() throws MissingParameterException {
     private String generate_term() {
 	switch (rnd.nextInt(10)) {
 	case 0: return "cat";
-	case 1: return "\"cat\"";
+	case 1: return "\\\"cat\\\"";
 	case 2: return "comp.os.linux";
 	case 3: return "xml:element";
 	case 4: return "<xml.element>";
diff --git a/src/main/java/org/z3950/zing/cql/CQLLexer.java b/src/main/java/org/z3950/zing/cql/CQLLexer.java
index 4294b6f..ff5aee3 100644
--- a/src/main/java/org/z3950/zing/cql/CQLLexer.java
+++ b/src/main/java/org/z3950/zing/cql/CQLLexer.java
@@ -69,19 +69,15 @@ else if (comp.equals("<>")) {
       //remember quote char
       char mark = c;
       qi++;
-      boolean escaped = false;
       buf.setLength(0); //reset buffer
-      while (qi < ql) {
-        if (!escaped && qs.charAt(qi) == mark) //terminator
-          break;
-        if (escaped && strchr("*?^\\", qs.charAt(qi))) //no escaping for d-quote
-          buf.append("\\");
-        if (!escaped && qs.charAt(qi) == '\\') { //escape-char
-          escaped = true;
+      while (qi < ql && qs.charAt(qi) != mark) {
+        if (qs.charAt(qi) == '\\') { //escape-char
+          if (qi == ql - 1) {
+            break; //unterminated
+          }
+          buf.append(qs.charAt(qi));
           qi++;
-          continue;
         }
-        escaped = false; //reset escape
         buf.append(qs.charAt(qi));
         qi++;
       }
diff --git a/src/main/java/org/z3950/zing/cql/CQLTermNode.java b/src/main/java/org/z3950/zing/cql/CQLTermNode.java
index 02a8229..a13a271 100644
--- a/src/main/java/org/z3950/zing/cql/CQLTermNode.java
+++ b/src/main/java/org/z3950/zing/cql/CQLTermNode.java
@@ -229,7 +229,7 @@ static String maybeQuote(String str) {
 	    str.indexOf('/') != -1 ||
 	    str.indexOf('(') != -1 ||
 	    str.indexOf(')') != -1) {
-	    str = '"' + str.replace("\"", "\\\"") + '"';
+	    str = '"' + str + '"';
 	}
 
 	return str;
diff --git a/src/test/resources/regression/06/03.xcql b/src/test/resources/regression/06/03.xcql
index 9db40ae..68b2dd5 100644
--- a/src/test/resources/regression/06/03.xcql
+++ b/src/test/resources/regression/06/03.xcql
@@ -3,5 +3,5 @@
   <relation>
     <value>=</value>
   </relation>
-  <term>^cat says "fish"</term>
+  <term>^cat says \"fish\"</term>
 </searchClause>
diff --git a/src/test/resources/regression/06/06.xcql b/src/test/resources/regression/06/06.xcql
index 9d38695..2a0cd96 100644
--- a/src/test/resources/regression/06/06.xcql
+++ b/src/test/resources/regression/06/06.xcql
@@ -3,5 +3,5 @@
   <relation>
     <value>=</value>
   </relation>
-  <term>^cat*fishdog"horse?</term>
+  <term>^cat*fishdog\"horse?</term>
 </searchClause>
diff --git a/src/test/resources/regression/12/01.xcql b/src/test/resources/regression/12/01.xcql
index c9fc4b6..b826cba 100644
--- a/src/test/resources/regression/12/01.xcql
+++ b/src/test/resources/regression/12/01.xcql
@@ -3,5 +3,5 @@
   <relation>
     <value>=</value>
   </relation>
-  <term>term\*\?\^</term>
+  <term>te\rm\*\?\^</term>
 </searchClause>

From f09d98ef85f59c30902da1d0dad9659dbd7b5bde Mon Sep 17 00:00:00 2001
From: Adam Dickmeiss <adam@indexdata.dk>
Date: Tue, 21 Oct 2025 12:07:02 +0200
Subject: [PATCH 2/2] Consider the unlikely bare double quote

---
 src/main/java/org/z3950/zing/cql/CQLGenerator.java | 2 +-
 src/main/java/org/z3950/zing/cql/CQLTermNode.java  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/main/java/org/z3950/zing/cql/CQLGenerator.java b/src/main/java/org/z3950/zing/cql/CQLGenerator.java
index 0b291a4..f22a7af 100644
--- a/src/main/java/org/z3950/zing/cql/CQLGenerator.java
+++ b/src/main/java/org/z3950/zing/cql/CQLGenerator.java
@@ -204,7 +204,7 @@ private String generate_base_relation() throws MissingParameterException {
     private String generate_term() {
 	switch (rnd.nextInt(10)) {
 	case 0: return "cat";
-	case 1: return "\\\"cat\\\"";
+	case 1: return "\"cat\\\"";  // A term with both bare quotes and escaped quotes
 	case 2: return "comp.os.linux";
 	case 3: return "xml:element";
 	case 4: return "<xml.element>";
diff --git a/src/main/java/org/z3950/zing/cql/CQLTermNode.java b/src/main/java/org/z3950/zing/cql/CQLTermNode.java
index a13a271..6fa042d 100644
--- a/src/main/java/org/z3950/zing/cql/CQLTermNode.java
+++ b/src/main/java/org/z3950/zing/cql/CQLTermNode.java
@@ -229,7 +229,7 @@ static String maybeQuote(String str) {
 	    str.indexOf('/') != -1 ||
 	    str.indexOf('(') != -1 ||
 	    str.indexOf(')') != -1) {
-	    str = '"' + str + '"';
+	    str = '"' + str.replaceAll("(?<!\\\\)\"", "\\\\\"") + '"';
 	}
 
 	return str;