From 25227d5c6c460cfd46ee872dcab0774d9984a465 Mon Sep 17 00:00:00 2001
From: Florian Stinglmayr <florian@n0la.org>
Date: Wed, 14 Feb 2018 18:31:52 +0000
Subject: [PATCH] make the parser reentrant

---
 Makefile.am      |  6 +++---
 lib/dice.c       | 27 ++++++++++++++++++++++-----
 lib/dice_lexer.l | 14 ++++++++++++--
 lib/dice_parse.y |  9 ++++++---
 4 files changed, 43 insertions(+), 13 deletions(-)

diff --git a/Makefile.am b/Makefile.am
index 8077840..08f40a4 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -2,10 +2,10 @@ AM_YFLAGS =		-d
 BUILT_SOURCES =		lib/dice_parse.h
 
 lib_LTLIBRARIES =	libdice.la
-libdice_la_SOURCES =	lib/dice.h \
-			lib/dice.c \
+libdice_la_SOURCES =	lib/dice_lexer.l \
 			lib/dice_parse.y \
-			lib/dice_lexer.l
+			lib/dice.h \
+			lib/dice.c
 
 AM_CFLAGS =		-Ilib
 
diff --git a/lib/dice.c b/lib/dice.c
index 5d98399..595931d 100644
--- a/lib/dice.c
+++ b/lib/dice.c
@@ -8,11 +8,17 @@
 #include <bsd/stdlib.h>
 #endif
 
-extern void *yy_scan_string(char const *s);
-extern void yy_delete_buffer(void *b);
+extern int yylex_init(void **state);
+extern int yylex_destroy(void *state);
+extern void yylex(void *state);
+extern void yy_switch_to_buffer(void *buffer, void *scanner);
+extern void *yy_scan_string(char const *s, void *scanner);
+extern void yy_delete_buffer(void *b, void *scanner);
 
 struct dice_
 {
+    int consumed;
+
     uint32_t amount;
     uint32_t sides;
 
@@ -77,6 +83,7 @@ dice_t dice_simple(uint32_t amount, uint32_t sides)
 
 dice_t dice_parse(char const *s)
 {
+    void *scanner = NULL;
     dice_t d = NULL;
     void *buffer = NULL;
     int ret = 0;
@@ -86,9 +93,14 @@ dice_t dice_parse(char const *s)
         return NULL;
     }
 
-    buffer = yy_scan_string(s);
-    ret = yyparse(d);
-    yy_delete_buffer(buffer);
+    yylex_init(&scanner);
+    buffer = yy_scan_string(s, scanner);
+    yy_switch_to_buffer(buffer, scanner);
+
+    ret = yyparse(scanner, d);
+
+    yy_delete_buffer(buffer, scanner);
+    yylex_destroy(scanner);
 
     if (ret) {
         dice_free(d);
@@ -176,3 +188,8 @@ bool dice_evaluate(dice_t d, dice_result_t **res, size_t *reslen)
 
     return true;
 }
+
+void dice_update_consumned(dice_t d, int offset)
+{
+    d->consumed += offset;
+}
diff --git a/lib/dice_lexer.l b/lib/dice_lexer.l
index 847ce53..1ec369b 100644
--- a/lib/dice_lexer.l
+++ b/lib/dice_lexer.l
@@ -1,9 +1,19 @@
+%option bison-bridge
+%option reentrant
+
 %{
 #include "dice.h"
 #include "dice_parse.h"
+
 %}
 
 %%
-[0-9]+ { yylval.integer = atoi(yytext); return TOK_INTEGER; }
-[d] return TOK_DICESEP;
+[0-9]+ {
+    yylval->integer = atoi(yytext);
+    return TOK_INTEGER;
+}
+
+[d] {
+    return TOK_DICESEP;
+}
 %%
diff --git a/lib/dice_parse.y b/lib/dice_parse.y
index 014a05b..dfa9438 100644
--- a/lib/dice_parse.y
+++ b/lib/dice_parse.y
@@ -1,11 +1,14 @@
-%parse-param {dice_t dice}
+%define api.pure full
+
+%parse-param {void *scanner} {dice_t dice}
+%lex-param {void *scanner}
 
 %{
 #include "dice.h"
 
-extern int yylex(void);
+extern int yylex(void *lval, void *scanner);
 
-void yyerror(dice_t dice, char const *err)
+void yyerror(void *scanner, dice_t dice, char const *err)
 {
 }