]> git.ozlabs.org Git - petitboot/blobdiff - discover/grub2/script.c
discover/grub2: Reimplement default options
[petitboot] / discover / grub2 / script.c
index fe65e2d43b5ce260fef3a0b896a9dc89cec934a5..0cf21967450efb3fbdf22c76f901c1c312b4d9d1 100644 (file)
@@ -1,17 +1,25 @@
 
 #include <sys/types.h>
 #include <string.h>
+#include <stdlib.h>
 
+#include <types/types.h>
 #include <talloc/talloc.h>
 
 #include "grub2.h"
 
 #define to_stmt_simple(stmt) \
        container_of(stmt, struct grub2_statement_simple, st)
+#define to_stmt_block(stmt) \
+       container_of(stmt, struct grub2_statement_block, st)
 #define to_stmt_if(stmt) \
        container_of(stmt, struct grub2_statement_if, st)
 #define to_stmt_menuentry(stmt) \
        container_of(stmt, struct grub2_statement_menuentry, st)
+#define to_stmt_function(stmt) \
+       container_of(stmt, struct grub2_statement_function, st)
+#define to_stmt_conditional(stmt) \
+       container_of(stmt, struct grub2_statement_conditional, st)
 
 struct env_entry {
        const char              *name;
@@ -19,6 +27,26 @@ struct env_entry {
        struct list_item        list;
 };
 
+struct grub2_symtab_entry {
+       const char              *name;
+       grub2_function          fn;
+       void                    *data;
+       struct list_item        list;
+};
+
+static struct grub2_symtab_entry *script_lookup_function(
+               struct grub2_script *script, const char *name)
+{
+       struct grub2_symtab_entry *entry;
+
+       list_for_each_entry(&script->symtab, entry, list) {
+               if (!strcmp(entry->name, name))
+                       return entry;
+       }
+
+       return NULL;
+}
+
 const char *script_env_get(struct grub2_script *script, const char *name)
 {
        struct env_entry *entry;
@@ -69,6 +97,24 @@ static bool is_delim(char c)
        return c == ' ' || c == '\t';
 }
 
+static bool option_is_default(struct grub2_script *script,
+               struct discover_boot_option *opt)
+{
+       unsigned int default_idx;
+       const char *var;
+       char *end;
+
+       var = script_env_get(script, "default");
+       if (!var)
+               return false;
+
+       default_idx = strtoul(var, &end, 10);
+       if (end != var && *end == '\0')
+               return default_idx == script->n_options;
+
+       return !strcmp(opt->option->name, var);
+}
+
 /* For non-double-quoted variable expansions, we may need to split the
  * variable's value into multiple argv items.
  *
@@ -190,7 +236,7 @@ static void process_expansions(struct grub2_script *script,
                argv->argv[i++] = word->text;
 }
 
-int statements_execute(struct grub2_script *script,
+static int statements_execute(struct grub2_script *script,
                struct grub2_statements *stmts)
 {
        struct grub2_statement *stmt;
@@ -207,7 +253,8 @@ int statement_simple_execute(struct grub2_script *script,
                struct grub2_statement *statement)
 {
        struct grub2_statement_simple *st = to_stmt_simple(statement);
-       struct grub2_command *cmd;
+       struct grub2_symtab_entry *entry;
+       char *pos;
        int rc;
 
        if (!st->argv)
@@ -218,35 +265,67 @@ int statement_simple_execute(struct grub2_script *script,
        if (!st->argv->argc)
                return 0;
 
-       cmd = script_lookup_command(script, st->argv->argv[0]);
-       if (!cmd) {
-               fprintf(stderr, "undefined command '%s'\n", st->argv->argv[0]);
+       /* is this a var=value assignment? */
+       pos = strchr(st->argv->argv[0], '=');
+       if (pos) {
+               char *name, *value;
+               name = st->argv->argv[0];
+               name = talloc_strndup(st, name, pos - name);
+               value = pos + 1;
+               script_env_set(script, name, value);
                return 0;
        }
 
-       rc = cmd->exec(script, st->argv->argc, st->argv->argv);
+       entry = script_lookup_function(script, st->argv->argv[0]);
+       if (!entry) {
+               fprintf(stderr, "undefined function '%s'\n", st->argv->argv[0]);
+               return 1;
+       }
+
+       rc = entry->fn(script, entry->data, st->argv->argc, st->argv->argv);
 
        return rc;
 }
 
-int statement_if_execute(struct grub2_script *script,
+int statement_block_execute(struct grub2_script *script,
                struct grub2_statement *statement)
 {
-       struct grub2_statement_if *st = to_stmt_if(statement);
-       struct grub2_statements *case_stmts;
+       struct grub2_statement_block *st = to_stmt_block(statement);
+       return statements_execute(script, st->statements);
+}
+
+/* returns 0 if the statement was executed, 1 otherwise */
+static int statement_conditional_execute(struct grub2_script *script,
+               struct grub2_statement *statement, bool *executed)
+{
+       struct grub2_statement_conditional *st = to_stmt_conditional(statement);
        int rc;
 
        rc = st->condition->exec(script, st->condition);
+       *executed = (!rc);
+       if (*executed)
+               rc = statements_execute(script, st->statements);
+
+       return rc;
+}
+
+int statement_if_execute(struct grub2_script *script,
+               struct grub2_statement *statement)
+{
+       struct grub2_statement_if *st = to_stmt_if(statement);
+       struct grub2_statement *conditional;
+       bool executed;
+       int rc;
 
-       if (rc == 0)
-               case_stmts = st->true_case;
-       else
-               case_stmts = st->false_case;
+       list_for_each_entry(&st->conditionals->list, conditional, list) {
+               rc = statement_conditional_execute(script,
+                               conditional, &executed);
+               if (executed)
+                       break;
+       }
 
-       if (case_stmts)
-               statements_execute(script, case_stmts);
-       else
-               rc = 0;
+       if (!executed && st->else_case)
+               rc = statements_execute(script, st->else_case);
 
        return rc;
 }
@@ -255,10 +334,61 @@ int statement_menuentry_execute(struct grub2_script *script,
                struct grub2_statement *statement)
 {
        struct grub2_statement_menuentry *st = to_stmt_menuentry(statement);
+       struct discover_boot_option *opt;
 
        process_expansions(script, st->argv);
+
+       opt = discover_boot_option_create(script->ctx, script->ctx->device);
+       if (st->argv->argc > 0) {
+               opt->option->name = talloc_strdup(opt, st->argv->argv[0]);
+       } else {
+               opt->option->name = talloc_strdup(opt, "(unknown)");
+       }
+       opt->option->id = talloc_asprintf(opt->option, "%s#%s",
+                       script->ctx->device->device->id,
+                       opt->option->name);
+
+       script->opt = opt;
+
        statements_execute(script, st->statements);
 
+       opt->option->is_default = option_is_default(script, opt);
+
+       discover_context_add_boot_option(script->ctx, opt);
+       script->n_options++;
+       script->opt = NULL;
+
+       return 0;
+}
+
+static int function_invoke(struct grub2_script *script,
+               void *data, int argc, char **argv)
+{
+       struct grub2_statement_function *fn = data;
+       char *name;
+       int i;
+
+       /* set positional parameters */
+       for (i = 0; i < argc; i++) {
+               name = talloc_asprintf(script, "$%d", i);
+               script_env_set(script, name, argv[i]);
+       }
+
+       return statements_execute(script, fn->body);
+}
+
+int statement_function_execute(struct grub2_script *script,
+               struct grub2_statement *statement)
+{
+       struct grub2_statement_function *st = to_stmt_function(statement);
+       const char *name;
+
+       if (st->name->type == GRUB2_WORD_VAR)
+               expand_var(script, st->name);
+
+       name = st->name->text;
+       script_register_function(script, name, function_invoke, st);
+
        return 0;
 }
 
@@ -275,23 +405,17 @@ static void init_env(struct grub2_script *script)
        list_add(&script->environment, &env->list);
 }
 
-struct grub2_command *script_lookup_command(struct grub2_script *script,
-               const char *name)
+void script_register_function(struct grub2_script *script,
+               const char *name, grub2_function fn,
+               void *data)
 {
-       struct grub2_command *command;
-
-       list_for_each_entry(&script->commands, command, list) {
-               if (!strcmp(command->name, name))
-                       return command;
-       }
-
-       return NULL;
-}
+       struct grub2_symtab_entry *entry;
 
-void script_register_command(struct grub2_script *script,
-               struct grub2_command *command)
-{
-       list_add(&script->commands, &command->list);
+       entry = talloc(script, struct grub2_symtab_entry);
+       entry->fn = fn;
+       entry->name = name;
+       entry->data = data;
+       list_add(&script->symtab, &entry->list);
 }
 
 
@@ -300,14 +424,17 @@ void script_execute(struct grub2_script *script)
        statements_execute(script, script->statements);
 }
 
-struct grub2_script *create_script(void *ctx)
+struct grub2_script *create_script(struct grub2_parser *parser,
+               struct discover_context *ctx)
 {
        struct grub2_script *script;
 
-       script = talloc(ctx, struct grub2_script);
+       script = talloc_zero(parser, struct grub2_script);
 
        init_env(script);
-       list_init(&script->commands);
+       script->ctx = ctx;
+
+       list_init(&script->symtab);
        register_builtins(script);
 
        return script;