From a1b67576352bb55769b8be805caf1baad59f7752 Mon Sep 17 00:00:00 2001
From: servostar <sven.vogel123@web.de>
Date: Sun, 23 Jun 2024 15:14:42 +0200
Subject: [PATCH] added: support for basic escape sequences

---
 src/lex/lexer.l |  5 ++++-
 src/lex/util.c  | 38 ++++++++++++++++++++++++++++++++++++++
 src/lex/util.h  |  2 ++
 3 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/src/lex/lexer.l b/src/lex/lexer.l
index 0491c3b..bfde8ff 100644
--- a/src/lex/lexer.l
+++ b/src/lex/lexer.l
@@ -98,7 +98,10 @@
     yytext = yytext +1;
     yytext[yyleng - 2] = 0;
     
-    DEBUG("\"%s\" tokenized with \'ValStr\'", yytext); yylval.string = mem_strdup(MemoryNamespaceLex, yytext); return(ValStr);};
+    DEBUG("\"%s\" tokenized with \'ValStr\'", yytext);
+    yylval.string = collapse_escape_sequences(yytext);
+    return(ValStr);
+};
 \"\"\"[^\"]*\"\"\" {
     yytext = yytext +3;
     yytext[yyleng - 6] = 0;
diff --git a/src/lex/util.c b/src/lex/util.c
index 83966da..ab412ec 100644
--- a/src/lex/util.c
+++ b/src/lex/util.c
@@ -84,3 +84,41 @@ int getNextLine(void) {
 
   return 0;
 }
+
+struct ConstEscSeq {
+    char* esc;
+    char* rep;
+};
+
+static struct ConstEscSeq sequences[] = {
+    {
+        "\\n",
+        "\n"
+    },
+    {
+        "\\\\",
+        "\\"
+    },
+    {
+        "\\t",
+        "\t"
+    },
+    {
+        "\\r",
+        "\r"
+    }
+};
+
+char* collapse_escape_sequences(char* string) {
+    GString* unesc = g_string_new(string);
+
+    for (int i = 0; i < 4; i++) {
+        g_string_replace(unesc, sequences[i].esc, sequences[i].rep, 0);
+    }
+
+    char* str = mem_strdup(MemoryNamespaceLex, unesc->str);
+
+    g_string_free(unesc, TRUE);
+
+    return str;
+}
diff --git a/src/lex/util.h b/src/lex/util.h
index 6939526..e973a29 100644
--- a/src/lex/util.h
+++ b/src/lex/util.h
@@ -36,4 +36,6 @@ int nextChar(char *dst);
  */
 int getNextLine(void);
 
+char* collapse_escape_sequences(char* string);
+
 #endif // LEX_UTIL_H_