discover/grub2: Allow EOF as a statement terminator

[petitboot] / discover / grub2 / parser.y

diff --git a/discover/grub2/parser.y b/discover/grub2/parser.y
index e13cd72a8f72e6358e7dfa7ab7387000b384efc4..292ce0725b6af6bdffecc8ddad80c9e11f660460 100644 (file)
--- a/discover/grub2/parser.y
+++ b/discover/grub2/parser.y
@@ -2,6 +2,7 @@
 %pure-parser
 %lex-param { yyscan_t scanner }
 %parse-param { struct grub2_parser *parser }
+%error-verbose
 
 %{
 #include <talloc/talloc.h>
@@ -10,7 +11,10 @@
 #include "parser.h"
 #include "lexer.h"
 
+static void print_token(FILE *fp, int type, YYSTYPE value);
+
 #define YYLEX_PARAM parser->scanner
+#define YYPRINT(f, t, v) print_token(f, t, v)
 
 static void yyerror(struct grub2_parser *, char const *s);
 %}
@@ -38,6 +42,7 @@ static void yyerror(struct grub2_parser *, char const *s);
 %token TOKEN_IN                "in"
 %token TOKEN_MENUENTRY         "menuentry"
 %token TOKEN_SELECT            "select"
+%token TOKEN_SUBMENU           "submenu"
 %token TOKEN_THEN              "then"
 %token TOKEN_TIME              "time"
 %token TOKEN_UTIL              "until"
@@ -45,6 +50,9 @@ static void yyerror(struct grub2_parser *, char const *s);
 
 %type <statement>      statement
 %type <statements>     statements
+%type <statement>      conditional
+%type <statement>      elif
+%type <statements>     elifs
 %type <argv>           words
 %type <word>           word
 
@@ -52,53 +60,75 @@ static void yyerror(struct grub2_parser *, char const *s);
 %token TOKEN_EOL
 %token TOKEN_DELIM
 %token <word> TOKEN_WORD
+%token TOKEN_EOF 0
 
 %start script
 %debug
 
 %%
 
-script: statements {
+script:        statements {
                parser->script->statements = $1;
        }
 
-statements: statement {
+eol:   TOKEN_EOL | TOKEN_EOF;
+
+statements: /* empty */ {
                $$ = create_statements(parser);
-               statement_append($$, $1);
        }
-       | statements statement {
+       | statements statement eol {
                statement_append($1, $2);
                $$ = $1;
        }
+       | statements TOKEN_EOL {
+               $$ = $1;
+       }
 
-statement: TOKEN_EOL {
-               $$ = NULL;
+conditional: statement TOKEN_EOL "then" TOKEN_EOL statements {
+               $$ = create_statement_conditional(parser, $1, $5);
        }
-       | words TOKEN_EOL {
+
+elif: "elif" TOKEN_DELIM conditional {
+               $$ = $3;
+      }
+
+elifs: /* empty */ {
+               $$ = create_statements(parser);
+       }
+       | elifs elif {
+               statement_append($1, $2);
+               $$ = $1;
+       }
+
+statement:
+       words {
                   $$ = create_statement_simple(parser, $1);
        }
        | '{' statements '}' {
                $$ = create_statement_block(parser, $2);
        }
-       | "if" TOKEN_DELIM statement
-               "then" TOKEN_EOL
-               statements
-               "fi" TOKEN_EOL {
-               $$ = create_statement_if(parser, $3, $6, NULL);
+       | "if" TOKEN_DELIM conditional elifs "fi" {
+               $$ = create_statement_if(parser, $3, $4, NULL);
        }
-       | "if" TOKEN_DELIM statement
-               "then" TOKEN_EOL
-               statements
+       | "if" TOKEN_DELIM conditional
+               elifs
                "else" TOKEN_EOL
                statements
-               "fi" TOKEN_EOL {
-               $$ = create_statement_if(parser, $3, $6, $9);
+               "fi" {
+               $$ = create_statement_if(parser, $3, $4, $7);
+       }
+       | "function" TOKEN_DELIM word TOKEN_DELIM '{' statements '}' {
+               $$ = create_statement_function(parser, $3, $6);
        }
        | "menuentry" TOKEN_DELIM words TOKEN_DELIM
-               '{' statements '}'
-               TOKEN_EOL {
+               '{' statements '}' {
                $$ = create_statement_menuentry(parser, $3, $6);
        }
+       | "submenu" TOKEN_DELIM words TOKEN_DELIM
+               '{' statements '}' {
+               /* we just flatten everything */
+               $$ = create_statement_block(parser, $6);
+       }
 
 words: word {
                $$ = create_argv(parser);
@@ -123,6 +153,13 @@ void yyerror(struct grub2_parser *parser, char const *s)
                        s, yyget_text(parser->scanner));
 }
 
+static void print_token(FILE *fp, int type, YYSTYPE value)
+{
+       if (type != TOKEN_WORD)
+               return;
+       fprintf(fp, "%s", value.word->text);
+}
+
 struct grub2_statements *create_statements(struct grub2_parser *parser)
 {
        struct grub2_statements *stmts = talloc(parser,
@@ -154,18 +191,33 @@ struct grub2_statement *create_statement_menuentry(struct grub2_parser *parser,
        return &stmt->st;
 }
 
-struct grub2_statement *create_statement_if(struct grub2_parser *parser,
+struct grub2_statement *create_statement_conditional(
+               struct grub2_parser *parser,
                struct grub2_statement *condition,
-               struct grub2_statements *true_case,
-               struct grub2_statements *false_case)
+               struct grub2_statements *statements)
+{
+       struct grub2_statement_conditional *stmt =
+               talloc(parser, struct grub2_statement_conditional);
+       stmt->st.type = STMT_TYPE_CONDITIONAL;
+       stmt->condition = condition;
+       stmt->statements = statements;
+       return &stmt->st;
+}
+
+struct grub2_statement *create_statement_if(struct grub2_parser *parser,
+               struct grub2_statement *conditional,
+               struct grub2_statements *elifs,
+               struct grub2_statements *else_case)
 {
        struct grub2_statement_if *stmt =
                talloc(parser, struct grub2_statement_if);
+
+       list_add(&elifs->list, &conditional->list);
+
        stmt->st.type = STMT_TYPE_IF;
        stmt->st.exec = statement_if_execute;
-       stmt->condition = condition;
-       stmt->true_case = true_case;
-       stmt->false_case = false_case;
+       stmt->conditionals = elifs;
+       stmt->else_case = else_case;
        return &stmt->st;
 }
 
@@ -180,6 +232,17 @@ struct grub2_statement *create_statement_block(struct grub2_parser *parser,
        return &stmt->st;
 }
 
+struct grub2_statement *create_statement_function(struct grub2_parser *parser,
+               struct grub2_word *name, struct grub2_statements *body)
+{
+       struct grub2_statement_function *stmt =
+               talloc(parser, struct grub2_statement_function);
+       stmt->st.exec = statement_function_execute;
+       stmt->name = name;
+       stmt->body = body;
+       return &stmt->st;
+}
+
 void statement_append(struct grub2_statements *stmts,
                struct grub2_statement *stmt)
 {
@@ -244,13 +307,15 @@ struct grub2_parser *grub2_parser_create(struct discover_context *ctx)
 void grub2_parser_parse(struct grub2_parser *parser, char *buf, int len)
 {
        YY_BUFFER_STATE bufstate;
+       int rc;
 
        bufstate = yy_scan_bytes(buf, len - 1, parser->scanner);
 
-       yyparse(parser);
+       rc = yyparse(parser);
 
        yy_delete_buffer(bufstate, parser->scanner);
 
-       script_execute(parser->script);
+       if (!rc)
+               script_execute(parser->script);
 }