From 3519c014e86f5ce651f196a4abb584404b24a10f Mon Sep 17 00:00:00 2001
From: overflowerror <mail@overflowerror.com>
Date: Thu, 20 May 2021 18:02:42 +0200
Subject: [PATCH] lexer and parser seem to work now

---
 src/main.c    | 13 +++++++++++++
 src/parser.y  | 26 +++++++++++++++++---------
 src/scanner.l | 32 ++++++++++++++++++--------------
 3 files changed, 48 insertions(+), 23 deletions(-)
 create mode 100644 src/main.c

diff --git a/src/main.c b/src/main.c
new file mode 100644
index 0000000..a31561d
--- /dev/null
+++ b/src/main.c
@@ -0,0 +1,13 @@
+
+#include <stdio.h>
+
+extern int yyparse();
+
+int main() {
+	return yyparse();
+}
+
+void yyerror(char* s) {
+	extern int yylineno;
+	fprintf(stderr, "%s (line %d)\n", s, yylineno);
+}
diff --git a/src/parser.y b/src/parser.y
index 2a0fd71..0ac7248 100644
--- a/src/parser.y
+++ b/src/parser.y
@@ -1,4 +1,12 @@
 
+%{
+
+int yylex();
+
+extern void yyerror(char*);
+
+%}
+
 %token SECTION TEXT COMMA END
 %token PARAMS_BEGIN PARAMS_END
 %token STATEMENT_BEGIN STATEMENT_END
@@ -11,20 +19,19 @@
 file: metaSection SECTION mainSection
 ;
 
-metaSection: PARAMS_BEGIN parameters PARAMS_END
-           | STATEMENT_BEGIN metaStatement STATEMENT_END
+metaSection: /* empty */
+           | PARAMS_BEGIN parameters PARAMS_END metaSection
+           | STATEMENT_BEGIN metaStatement STATEMENT_END metaSection
 ;
 
 parameters: /* empty */
           | parameter moreParameters
 ;
 
-parameter: /* empty */
-         | TEXT parameter
+parameter: TEXT texts
 ;         
 
 moreParameters: /* empty */
-              | COMMA /* allow trailing commas */
               | COMMA parameter moreParameters
 ;
 
@@ -40,10 +47,11 @@ mainSection: /* empty */
 blockStatement: statement
 ;
 
-statement: TEXT /* statement can't be empty */
-         | TEXT statement
+statement: TEXT texts
 ;
 
-output: TEXT /* output can't be empty */
-      | TEXT output
+output: TEXT texts
 ;
+
+texts: /* empty */
+     | TEXT texts
diff --git a/src/scanner.l b/src/scanner.l
index 4bc6adc..56121c4 100644
--- a/src/scanner.l
+++ b/src/scanner.l
@@ -11,7 +11,8 @@ statement_end		"%}"
 output_begin		"{{"
 output_end			"}}"
 
-block_end			"end"
+block_end_token	"end"
+block_end			{whitespace}*{block_end_token}{whitespace}*
 
 type_prefixes		"enum"|"struct"
 type_prefix			{type_prefixes}{whitespace}+
@@ -19,18 +20,16 @@ type_pointer		{whitespace}*"*"
 type					{type_prefix}?[a-zA-Z0-9_]+{type_pointer}?
 
 %option noyywrap
-%option nodefault
 %option nounput
 %option noinput
 %option yylineno
 
-%x PARAMS
-%x STATEMENT
-%x OUTPUT
 %x META_SECTION
 %x MAIN_SECTION
 
-%s META_SECTION
+%x PARAMS
+%x STATEMENT
+%x OUTPUT
 
 %%
 
@@ -39,24 +38,29 @@ type					{type_prefix}?[a-zA-Z0-9_]+{type_pointer}?
 	#include <stdlib.h>
 	#include <stdio.h>
 	
+	#include "y.tab.h"
+	
 	bool isMetaSection = true;
 %}
 
-<META_SECTION>{params_begin}		{ BEGIN(PARAMS); return PARAMS_BEGIN; }
-<META_SECTION>{statement_begin}	{ BEGIN(STATEMENT); return STATEMENT_BEGIN; }
-<META_SECTION>{section}				{ isMetaSection = false; BEGIN(MAIN_SECTION); }
-<META_SECTION>{output_begin}		{ fprintf(stderr, "error: output block not allowed in meta section (line %d)\n", yylineno); exit(1); }
-<META_SECTION>.						{ fprintf(stderr, "error: raw text not allowed in meta section (line %d)\n", yylineno); exit(1); }
+<INITIAL,META_SECTION>{params_begin}		{ BEGIN(PARAMS); return PARAMS_BEGIN; }
+<INITIAL,META_SECTION>{statement_begin}	{ BEGIN(STATEMENT); return STATEMENT_BEGIN; }
+<INITIAL,META_SECTION>{section}				{ isMetaSection = false; BEGIN(MAIN_SECTION); return SECTION; }
+<INITIAL,META_SECTION>{output_begin}		{ fprintf(stderr, "error: output block not allowed in meta section (line %d)\n", yylineno); exit(1); }
+<INITIAL,META_SECTION>{whitespace}+		{ /* ignore whitespaces */ }
+<INITIAL,META_SECTION>.						{ fprintf(stderr, "error: raw text not allowed in meta section (line %d)\n", yylineno); exit(1); }
 
 <PARAMS>{type}							{ return TEXT; }
 <PARAMS>{params_end}					{ BEGIN(META_SECTION); return PARAMS_END; }
 <PARAMS>","								{ return COMMA; }
 <PARAMS>{whitespace}+				{ /* ignore whitespaces */ }
-<PARAMS>$								{ return TEXT; /* catch $ as text */ }
+<PARAMS>"$"								{ return TEXT; /* catch $ as text */ }
 <PARAMS>.								{ fprintf(stderr, "error: illegal token '%s' in parameter block (line %d)\n", yytext, yylineno); exit(1); }
 
-<STATEMENT>[^%]+						{ return TEXT; }
-<STATEMENT>%							{ return TEXT; /* catch % as text */ }
+<STATEMENT>[^%e]+						{ return TEXT; }
+<STATEMENT>{block_end}				{ return END; }
+<STATEMENT>"%"							{ return TEXT; /* catch % as text */ }
+<STATEMENT>"e"							{ return TEXT; /* catch e as text */ }
 <STATEMENT>{statement_end}			{ if (isMetaSection) BEGIN(META_SECTION); else BEGIN(MAIN_SECTION); return STATEMENT_END; }
 
 <MAIN_SECTION>{params_begin}		{ fprintf(stderr, "warning: parameter block not allowed in main section (line %d); assuming to be text\n", yylineno); return TEXT; }