Make the scanner and the parser reentrant and reduce non-namespaced symbols

3 files changed, 52 insertions, 19 deletions

diff --git a/src/lexer.l b/src/lexer.l
index ed0fc34..1c7d940 100644
--- a/src/lexer.l
+++ b/src/lexer.l
@@ -1,4 +1,6 @@
-%option noyywrap
+%option noyywrap reentrant bison-bridge
+%option outfile="lex.yy.c"
+%option prefix="ccmmc_parser_"
 %{
 #ifdef HAVE_CONFIG_H
 # include "config.h"
@@ -14,6 +16,8 @@
 #include <string.h>
 
 int line_number = 1;
+
+#define YYSTYPE CCMMC_PARSER_STYPE
 %}
 
 letter          [A-Za-z]
@@ -65,8 +69,8 @@ ERROR           .
                     size_t i;
                     char *reserved[] = {"return", "typedef", "if", "else",
                         "int", "float", "for", "void", "while"};
-                    enum yytokentype reserved_token[] = {RETURN, TYPEDEF,
-                        IF, ELSE, INT, FLOAT, FOR, VOID, WHILE};
+                    enum ccmmc_parser_tokentype reserved_token[] = {RETURN,
+                        TYPEDEF, IF, ELSE, INT, FLOAT, FOR, VOID, WHILE};
                     static_assert(
                         SIZEOF_ARRAY(reserved) == SIZEOF_ARRAY(reserved_token),
                         "Reserved words array and reserved tokens array "
@@ -83,8 +87,8 @@ ERROR           .
                         else
                             ptr->counter++;
                     }
-                    yylval.lexeme = strdup(yytext);
-                    ERR_FATAL_CHECK(yylval.lexeme, strdup);
+                    yylval->lexeme = strdup(yytext);
+                    ERR_FATAL_CHECK(yylval->lexeme, strdup);
                     return ID;
                 }
 {CONST_INT}     {
@@ -93,7 +97,7 @@ ERROR           .
                     ERR_FATAL_CHECK(p, malloc);
                     p->const_type = INTEGERC;
                     p->const_u.intval = atoi(yytext);
-                    yylval.const1 = p;
+                    yylval->const1 = p;
                     return CONST;
                 }
 {CONST_FLOAT}   {
@@ -102,7 +106,7 @@ ERROR           .
                     ERR_FATAL_CHECK(p, malloc);
                     p->const_type = FLOATC;
                     p->const_u.fval = atof(yytext);
-                    yylval.const1 = p;
+                    yylval->const1 = p;
                     return CONST;
                 }
 {CONST_STRING}  {
@@ -112,7 +116,7 @@ ERROR           .
                     p->const_type = STRINGC;
                     p->const_u.sc = strdup(yytext);
                     ERR_FATAL_CHECK(p->const_u.sc, strdup);
-                    yylval.const1 = p;
+                    yylval->const1 = p;
                     return CONST;
                 }
 {COMMENT}       {
diff --git a/src/main.c b/src/main.c
index 2370f5a..cc52b13 100644
--- a/src/main.c
+++ b/src/main.c
@@ -2,6 +2,8 @@
 # include "config.h"
 #endif
 
+typedef void* yyscan_t;
+
 #include "ast.h"
 #include "common.h"
 #include "libparser_a-parser.h"
@@ -16,6 +18,10 @@
 extern FILE *yyin;
 extern AST_NODE *prog;
 
+extern int ccmmc_parser_lex_init(yyscan_t *scanner);
+extern int ccmmc_parser_lex_destroy(yyscan_t *scanner);
+extern int ccmmc_parser_set_in(FILE *source_handle, yyscan_t scanner);
+
 const char *ccmmc_main_name;
 
 int main (int argc, char **argv)
@@ -30,14 +36,29 @@ int main (int argc, char **argv)
         exit(1);
     }
 
-    const char *filename = argv[1];
-    yyin = fopen(filename, "r");
-    if (yyin == NULL) {
-        fprintf(stderr, "%s: %s: %s\n", name, filename, ERR_MSG);
+    const char *source_name = argv[1];
+    FILE *source_handle = fopen(source_name, "r");
+    if (source_handle == NULL) {
+        fprintf(stderr, "%s: %s: %s\n", name, source_name, ERR_MSG);
         exit(1);
     }
 
-    yyparse();
+    yyscan_t scanner;
+    ccmmc_parser_lex_init(&scanner);
+    ccmmc_parser_set_in(source_handle, scanner);
+    switch (ccmmc_parser_parse(scanner)) {
+        case 1:
+            fprintf(stderr, "%s: failed because of invalid input\n", name);
+            exit(1);
+        case 2:
+            fprintf(stderr, "%s: failed because of memory exhaustion\n", name);
+            exit(1);
+        default:
+            ; // silence warnings
+    }
+    ccmmc_parser_lex_destroy(scanner);
+
+    fclose(source_handle);
     printGV(prog, NULL);
     return 0;
 }
diff --git a/src/parser.y b/src/parser.y
index a837259..d90aaa7 100644
--- a/src/parser.y
+++ b/src/parser.y
@@ -1,20 +1,22 @@
+%define api.prefix {ccmmc_parser_}
+%define api.pure full
+%lex-param {yyscan_t scanner}
+%parse-param {yyscan_t scanner}
 %{
 #ifdef HAVE_CONFIG_H
 # include "config.h"
 #endif
 
+typedef void* yyscan_t;
+
 #include "ast.h"
 
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
-extern int yylex(void);
-static void yyerror(const char *mesg);
-
 AST_NODE *prog;
 
-extern char *yytext;
 extern int line_number;
 extern int g_anyErrorOccur;
 %}
@@ -25,6 +27,12 @@ extern int g_anyErrorOccur;
     AST_NODE  *node;
 };
 
+%{
+extern char *ccmmc_parser_get_text(yyscan_t scanner);
+extern int ccmmc_parser_lex(CCMMC_PARSER_STYPE *yylval, yyscan_t scanner);
+static void ccmmc_parser_error(yyscan_t scanner, const char *mesg);
+%}
+
 %token <lexeme>ID
 %token <const1>CONST
 %token VOID
@@ -686,10 +694,10 @@ dim_list    : dim_list DL_LBRACK expr DL_RBRACK
 
 %%
 
-static void yyerror(const char *mesg)
+static void ccmmc_parser_error(yyscan_t scanner, const char *mesg)
 {
     fprintf(stderr, "Error found in Line \t%d\tnext token: \t%s\n",
-        line_number, yytext);
+        line_number, ccmmc_parser_get_text(scanner));
     exit(1);
 }