feat: Begin of proprocessor; including files now works

compiler/src/lexer.l

@@ -16,6 +16,8 @@ in      "in"
 char    "'"([^\\]|[\\]n|[\\]t|[\\]{2})"'"
 id		[a-zA-Z_][a-zA-Z0-9_]*
 
+include "#include"
+
 %option noyywrap
 %option nodefault
 %option nounput
@@ -29,6 +31,7 @@ id		[a-zA-Z_][a-zA-Z0-9_]*
 %{
 
 #include <stdlib.h>
+#include <stdio.h>
 #include <stdbool.h>
 #include <string.h>
 
@@ -37,6 +40,11 @@ id		[a-zA-Z_][a-zA-Z0-9_]*
 
 #include "y.tab.h"
 
+extern void push_file_to_yy_stack(FILE* file) {
+    YY_BUFFER_STATE state = yy_create_buffer(file, YY_BUF_SIZE);
+    yypush_buffer_state(state);
+}
+
 char char_escape(const char* yytext) {
     if (yytext[1] == '\\') {
         if (yytext[2] == '\\')     return '\\';
@@ -66,6 +74,8 @@ strbuf_t strbuf = NULL;
 
 <INITIAL>"//"[^\n]*    { /* single line comment */ }
 
+<INITIAL>{include}  { return PRE_INCLUDE; }
+
 <INITIAL>";"		{ return SEMICOLON; }
 
 <INITIAL>\"		    { BEGIN STRING; strbuf_clear(strbuf); }
@@ -127,4 +137,11 @@ strbuf_t strbuf = NULL;
 <INITIAL>{id}		{ yylval.id = strdup(yytext); return ID; }
 <INITIAL>{whitespace}+	{ }
 
+<<EOF>>             {
+                        yypop_buffer_state();
+                        if (!YY_CURRENT_BUFFER) {
+                            yyterminate();
+                        }
+                    }
+
 <INITIAL>.		    { lex_panic("unknown token: %s\n", yytext); }

compiler/src/parser.y

@@ -12,7 +12,9 @@
 
 #include "ast.h"
 
+#define yylex preproc_lex
 int yylex(void);
+
 void yyerror(const char*);
 
 extern struct block* program;
@@ -76,6 +78,8 @@ extern struct block* program;
 %token RMAP
 %token IN
 
+%token PRE_INCLUDE
+
 %start file
 
 %%

compiler/src/preprocessor.c

@@ -0,0 +1,41 @@
+#include <stdio.h>
+
+#include "y.tab.h"
+
+#include <error.h>
+
+void push_file_to_yy_stack(FILE*);
+int yylex(void);
+
+extern char* yytext;
+extern YYSTYPE yylval;
+
+static void handle_include(void) {
+    int token = yylex();
+
+    if (token != STR) {
+        fprintf(stderr, "preprocessor: include: file name expected, got: %s\n", yytext);
+        panic("processor syntax error");
+    }
+
+    const char* filename = yylval.str;
+    FILE* file = fopen(filename, "r");
+    if (file == NULL) {
+        panic("file not found");
+    }
+
+    push_file_to_yy_stack(file);
+}
+
+extern int preproc_lex(void) {
+    int token = yylex();
+
+    switch(token) {
+        case PRE_INCLUDE:
+            handle_include();
+            token = yylex();
+            break;
+    }
+    return token;
+}
+

compiler/test/cases/025a-preproc-include.in

@@ -0,0 +1,3 @@
+#include "025a-preproc-include.include"
+
+print(" World!\n");

compiler/test/cases/025a-preproc-include.include

@@ -0,0 +1 @@
+print("Hello,");

compiler/test/cases/025a-preproc-include.out

@@ -0,0 +1,2 @@
+[-]++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++>[-]+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++>[-]++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++>[-]++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++>[-]+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++>[-]++++++++++++++++++++++++++++++++++++++++++++<<<<<.>.>.>.>.>.
+<<<<<[-]++++++++++++++++++++++++++++++++>[-]+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++>[-]+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++>[-]++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++>[-]++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++>[-]++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++>[-]+++++++++++++++++++++++++++++++++>[-]++++++++++<<<<<<<.>.>.>.>.>.>.>.