merged with mainline

script/execute.c

@@ -26,13 +26,24 @@
 #include <grub/lib/arg.h>
 #include <grub/normal.h>
 
+/* Max digits for a char is 3 (0xFF is 255), similarly for an int it
+   is sizeof (int) * 3, and one extra for a possible -ve sign.  */
+#define ERRNO_DIGITS_MAX  (sizeof (int) * 3 + 1)
+
 static grub_err_t
 grub_script_execute_cmd (struct grub_script_cmd *cmd)
 {
+  int ret;
+  char errnobuf[ERRNO_DIGITS_MAX + 1];
+
   if (cmd == 0)
     return 0;
 
-  return cmd->exec (cmd);
+  ret = cmd->exec (cmd);
+
+  grub_snprintf (errnobuf, sizeof (errnobuf), "%d", ret);
+  grub_env_set ("?", errnobuf);
+  return ret;
 }
 
 #define ARG_ALLOCATION_UNIT  (32 * sizeof (char))
@@ -260,13 +271,14 @@ grub_script_execute_cmdline (struct grub_script_cmd *cmd)
 grub_err_t
 grub_script_execute_cmdblock (struct grub_script_cmd *cmd)
 {
+  int ret = 0;
   struct grub_script_cmdblock *cmdblock = (struct grub_script_cmdblock *) cmd;
 
   /* Loop over every command and execute it.  */
   for (cmd = cmdblock->cmdlist; cmd; cmd = cmd->next)
-    grub_script_execute_cmd (cmd);
+    ret = grub_script_execute_cmd (cmd);
 
-  return 0;
+  return ret;
 }
 
 /* Execute an if statement.  */
@@ -317,6 +329,26 @@ grub_script_execute_cmdfor (struct grub_script_cmd *cmd)
   return result;
 }
 
+/* Execute a "while" or "until" command.  */
+grub_err_t
+grub_script_execute_cmdwhile (struct grub_script_cmd *cmd)
+{
+  int cond;
+  int result;
+  struct grub_script_cmdwhile *cmdwhile = (struct grub_script_cmdwhile *) cmd;
+
+  result = 0;
+  do {
+    cond = grub_script_execute_cmd (cmdwhile->cond);
+    if (cmdwhile->until ? !cond : cond)
+      break;
+
+    result = grub_script_execute_cmd (cmdwhile->list);
+  } while (1); /* XXX Put a check for ^C here */
+
+  return result;
+}
+
 /* Execute the menu entry generate statement.  */
 grub_err_t
 grub_script_execute_menuentry (struct grub_script_cmd *cmd)

script/parser.y

@@ -74,8 +74,10 @@
 %token <arg> GRUB_PARSER_TOKEN_WORD      "word"
 
 %type <arglist> word argument arguments0 arguments1
-%type <cmd> script_init script grubcmd ifcmd forcmd command
-%type <cmd> commands1 menuentry statement
+
+%type <cmd> script_init script
+%type <cmd> grubcmd ifclause ifcmd forcmd whilecmd untilcmd
+%type <cmd> command commands1 menuentry statement
 
 %pure-parser
 %lex-param   { struct grub_parser_param *state };
@@ -171,9 +173,11 @@ grubcmd: word arguments0
 ;
 
 /* A single command.  */
-command: grubcmd { $$ = $1; }
-       | ifcmd   { $$ = $1; }
-       | forcmd  { $$ = $1; }
+command: grubcmd  { $$ = $1; }
+       | ifcmd    { $$ = $1; }
+       | forcmd   { $$ = $1; }
+       | whilecmd { $$ = $1; }
+       | untilcmd { $$ = $1; }
 ;
 
 /* A list of commands. */
@@ -224,18 +228,28 @@ menuentry: "menuentry"
            }
 ;
 
-if: "if" { grub_script_lexer_ref (state->lexerstate); }
+ifcmd: "if"
+	{
+	  grub_script_lexer_ref (state->lexerstate);
+	}
+	ifclause "fi"
+	{
+	  $$ = $3;
+	  grub_script_lexer_deref (state->lexerstate);
+	}
 ;
-ifcmd: if commands1 delimiters1 "then" commands1 delimiters1 "fi"
-       {
-         $$ = grub_script_create_cmdif (state, $2, $5, 0);
-         grub_script_lexer_deref (state->lexerstate);
-       }
-     | if commands1 delimiters1 "then" commands1 delimiters1 "else" commands1 delimiters1 "fi"
-       {
-         $$ = grub_script_create_cmdif (state, $2, $5, $8);
-         grub_script_lexer_deref (state->lexerstate);
-       }
+ifclause: commands1 delimiters1 "then" commands1 delimiters1
+	  {
+	    $$ = grub_script_create_cmdif (state, $1, $4, 0);
+	  }
+	| commands1 delimiters1 "then" commands1 delimiters1 "else" commands1 delimiters1
+	  {
+	    $$ = grub_script_create_cmdif (state, $1, $4, $7);
+	  }
+	| commands1 delimiters1 "then" commands1 delimiters1 "elif" ifclause
+	  {
+	    $$ = grub_script_create_cmdif (state, $1, $4, $7);
+	  }
 ;
 
 forcmd: "for" "name"
@@ -248,3 +262,25 @@ forcmd: "for" "name"
 	  grub_script_lexer_deref (state->lexerstate);
 	}
 ;
+
+whilecmd: "while"
+          {
+	    grub_script_lexer_ref (state->lexerstate);
+          }
+          commands1 delimiters1 "do" commands1 delimiters1 "done"
+	  {
+	    $$ = grub_script_create_cmdwhile (state, $3, $6, 0);
+	    grub_script_lexer_deref (state->lexerstate);
+	  }
+;
+
+untilcmd: "until"
+          {
+	    grub_script_lexer_ref (state->lexerstate);
+          }
+          commands1 delimiters1 "do" commands1 delimiters1 "done"
+	  {
+	    $$ = grub_script_create_cmdwhile (state, $3, $6, 1);
+	    grub_script_lexer_deref (state->lexerstate);
+	  }
+;

script/script.c

@@ -245,6 +245,28 @@ grub_script_create_cmdfor (struct grub_parser_param *state,
   return (struct grub_script_cmd *) cmd;
 }
 
+/* Create a "while" or "until" command.  */
+struct grub_script_cmd *
+grub_script_create_cmdwhile (struct grub_parser_param *state,
+			     struct grub_script_cmd *cond,
+			     struct grub_script_cmd *list,
+			     int is_an_until_loop)
+{
+  struct grub_script_cmdwhile *cmd;
+
+  cmd = grub_script_malloc (state, sizeof (*cmd));
+  if (! cmd)
+    return 0;
+
+  cmd->cmd.exec = grub_script_execute_cmdwhile;
+  cmd->cmd.next = 0;
+  cmd->cond = cond;
+  cmd->list = list;
+  cmd->until = is_an_until_loop;
+
+  return (struct grub_script_cmd *) cmd;
+}
+
 /* Create a command that adds a menu entry to the menu.  Title is an
    argument that is parsed to generate a string that can be used as
    the title.  The sourcecode for this entry is passed in SOURCECODE.