From 7846dbdbc979f8c4980116532fa6ffdcbc94ff1a Mon Sep 17 00:00:00 2001
From: Ben Siraphob <bensiraphob@gmail.com>
Date: Mon, 24 Jul 2023 11:22:31 +0700
Subject: [PATCH] Add C grammar

---
 grammars/c.gbnf | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)
 create mode 100644 grammars/c.gbnf

diff --git a/grammars/c.gbnf b/grammars/c.gbnf
new file mode 100644
index 000000000..4a0331dd2
--- /dev/null
+++ b/grammars/c.gbnf
@@ -0,0 +1,42 @@
+root ::= (declaration)*
+
+declaration ::= dataType identifier "(" parameter? ")" "{" statement* "}"
+
+dataType  ::= "int" ws | "float" ws | "char" ws
+identifier ::= [a-zA-Z_] [a-zA-Z_0-9]*
+
+parameter ::= dataType identifier
+
+statement ::=
+    ( dataType identifier ws "=" ws expression ";" ) |
+    ( identifier ws "=" ws expression ";" ) |
+    ( identifier ws "(" argList? ")" ";" ) |
+    ( "return" ws expression ";" ) |
+    ( "while" "(" condition ")" "{" statement* "}" ) |
+    ( "for" "(" forInit ";" ws condition ";" ws forUpdate ")" "{" statement* "}" ) |
+    ( "if" "(" condition ")" "{" statement* "}" ("else" "{" statement* "}")? ) |
+    ( singleLineComment ) |
+    ( multiLineComment )
+
+forInit ::= dataType identifier ws "=" ws expression | identifier ws "=" ws expression
+forUpdate ::= identifier ws "=" ws expression
+
+condition ::= expression relationOperator expression
+relationOperator ::= ("<=" | "<" | "==" | "!=" | ">=" | ">")
+
+expression ::= term (("+" | "-") term)*
+term ::= factor(("*" | "/") factor)*
+
+factor ::= identifier | number | unaryTerm | funcCall | parenExpression
+unaryTerm ::= "-" factor
+funcCall ::= identifier "(" argList? ")"
+parenExpression ::= "(" ws expression ws ")"
+
+argList ::= expression ("," ws expression)*
+
+number ::= [0-9]+
+
+singleLineComment ::= "//" [^\n]* "\n"
+multiLineComment ::= "/*" ( [^*] | ("*" [^/]) )* "*/"
+
+ws ::= ([ \t\n]+)