discover/grub2: Implement 'elif'

Rather than just having one conditional in an if statement, we use a
list of conditionals instead. This allows us to implement elif.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>

diff --git a/discover/grub2/grub2.h b/discover/grub2/grub2.h
index 7f4a8345e666ff7ac78012320610ed07fdfe9c76..c7f43de252e9623732e699005df535bf0327f583 100644 (file)
--- a/discover/grub2/grub2.h
+++ b/discover/grub2/grub2.h
@@ -68,7 +68,7 @@ struct grub2_statement_conditional {
 
 struct grub2_statement_if {
        struct grub2_statement  st;
-       struct grub2_statement  *conditional;
+       struct grub2_statements *conditionals;
        struct grub2_statements *else_case;
 };
 
@@ -114,6 +114,7 @@ struct grub2_statement *create_statement_conditional(
 
 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 *create_statement_block(struct grub2_parser *parser,

diff --git a/discover/grub2/parser.y b/discover/grub2/parser.y
index 52dac9c7b27ee28d804010f3233279988205acd9..81856dfcaa5a2002fce07a78460a6e1ddb0015d6 100644 (file)
--- a/discover/grub2/parser.y
+++ b/discover/grub2/parser.y
@@ -48,6 +48,8 @@ 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
 
@@ -80,6 +82,18 @@ conditional: statement TOKEN_EOL "then" TOKEN_EOL statements {
                $$ = create_statement_conditional(parser, $1, $5);
        }
 
+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);
@@ -87,14 +101,15 @@ statement:
        | '{' statements '}' {
                $$ = create_statement_block(parser, $2);
        }
-       | "if" TOKEN_DELIM conditional "fi" {
-               $$ = create_statement_if(parser, $3, NULL);
+       | "if" TOKEN_DELIM conditional elifs "fi" {
+               $$ = create_statement_if(parser, $3, $4, NULL);
        }
        | "if" TOKEN_DELIM conditional
+               elifs
                "else" TOKEN_EOL
                statements
                "fi" {
-               $$ = create_statement_if(parser, $3, $6);
+               $$ = create_statement_if(parser, $3, $4, $7);
        }
        | "function" TOKEN_DELIM word TOKEN_DELIM '{' statements '}' {
                $$ = create_statement_function(parser, $3, $6);
@@ -178,13 +193,17 @@ struct grub2_statement *create_statement_conditional(
 
 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->conditional = conditional;
+       stmt->conditionals = elifs;
        stmt->else_case = else_case;
        return &stmt->st;
 }

diff --git a/discover/grub2/script.c b/discover/grub2/script.c
index c0d6e1a4e4a31affa291713b0351f816ac16afed..239ae38f5e67306408e7c386abc050b03ec5d4d6 100644 (file)
--- a/discover/grub2/script.c
+++ b/discover/grub2/script.c
@@ -277,10 +277,12 @@ int statement_if_execute(struct grub2_script *script,
        bool executed;
        int rc;
 
-       conditional = st->conditional;
-
-       rc = statement_conditional_execute(script,
-                       conditional, &executed);
+       list_for_each_entry(&st->conditionals->list, conditional, list) {
+               rc = statement_conditional_execute(script,
+                               conditional, &executed);
+               if (executed)
+                       break;
+       }
 
        if (!executed && st->else_case)
                rc = statements_execute(script, st->else_case);