Hi,
Attached patch adds while and until commands support to GRUB script.
It is also available in people/bvk/while-loop-support branch. This
doesn't have any unit tests yet -- i am still thinking of how to break
out of the loop, after few iterations. Also, i am not sure how to
handle Ctrl-C to break out of the loop, if at all we want to support
it :-(
thanks,
--
bvk.chaitanya
=== modified file 'ChangeLog.scripting'
--- ChangeLog.scripting 2009-12-26 04:07:41 +0000
+++ ChangeLog.scripting 2009-12-26 05:05:37 +0000
@@ -1,3 +1,17 @@
+2009-12-26 BVK Chaitanya <bvk.gro...@gmail.com>
+
+ * include/grub/script_sh.h: New function prototypes for
+ grub_script_create_cmdwhile and grub_script_execute_cmdwhile.
+ * script/parser.y ("whilecmd"): New grammar rule for while
+ command.
+ ("untilcmd"): New grammar rule for until command.
+ * script/script.c (grub_script_create_cmdwhile): Creates a
+ while/until command object.
+ * script/execute.c (grub_script_execute_cmdwhile): Executes a
+ while/until command object.
+ * util/grub-script-check.c (grub_script_execute_cmdwhile): Dummy
+ stub for syntax checking while/until statements.
+
2009-12-25 BVK Chaitanya <bvk.gro...@gmail.com>
* include/grub/script_sh.h (grub_script_arg_type_t): New types
=== modified file 'include/grub/script_sh.h'
--- include/grub/script_sh.h 2009-12-26 04:07:41 +0000
+++ include/grub/script_sh.h 2009-12-26 04:51:55 +0000
@@ -121,6 +121,21 @@
struct grub_script_cmd *list;
};
+/* A while/until command. */
+struct grub_script_cmdwhile
+{
+ struct grub_script_cmd cmd;
+
+ /* The command list used as condition. */
+ struct grub_script_cmd *cond;
+
+ /* The command list executed in each loop. */
+ struct grub_script_cmd *list;
+
+ /* The flag to indicate this as "until" loop. */
+ int until;
+};
+
/* A menu entry generate statement. */
struct grub_script_cmd_menuentry
{
@@ -236,6 +251,12 @@
struct grub_script_cmd *list);
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_cmd *
grub_script_create_cmdmenu (struct grub_parser_param *state,
struct grub_script_arglist *arglist,
char *sourcecode,
@@ -284,6 +305,7 @@
grub_err_t grub_script_execute_cmdblock (struct grub_script_cmd *cmd);
grub_err_t grub_script_execute_cmdif (struct grub_script_cmd *cmd);
grub_err_t grub_script_execute_cmdfor (struct grub_script_cmd *cmd);
+grub_err_t grub_script_execute_cmdwhile (struct grub_script_cmd *cmd);
grub_err_t grub_script_execute_menuentry (struct grub_script_cmd *cmd);
/* Execute any GRUB pre-parsed command or script. */
=== modified file 'script/execute.c'
--- script/execute.c 2009-12-26 04:07:41 +0000
+++ script/execute.c 2009-12-26 04:45:21 +0000
@@ -296,6 +296,26 @@
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) || (!cmdwhile->until && 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)
=== modified file 'script/parser.y'
--- script/parser.y 2009-12-26 03:51:24 +0000
+++ script/parser.y 2009-12-26 04:26:28 +0000
@@ -76,8 +76,9 @@
%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 ifcmd forcmd whilecmd untilcmd
+%type <cmd> command commands1 menuentry statement
%pure-parser
%error-verbose
@@ -179,9 +180,11 @@
;
/* 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. */
@@ -261,3 +264,25 @@
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);
+ }
+;
=== modified file 'script/script.c'
--- script/script.c 2009-12-26 03:51:24 +0000
+++ script/script.c 2009-12-26 04:31:30 +0000
@@ -230,6 +230,28 @@
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.
=== modified file 'util/grub-script-check.c'
--- util/grub-script-check.c 2009-12-26 03:51:24 +0000
+++ util/grub-script-check.c 2009-12-26 04:54:43 +0000
@@ -84,6 +84,12 @@
}
grub_err_t
+grub_script_execute_cmdwhile (struct grub_script_cmd *cmd __attribute__
((unused)))
+{
+ return 0;
+}
+
+grub_err_t
grub_script_execute_menuentry (struct grub_script_cmd *cmd)
{
struct grub_script_cmd_menuentry *menu;
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