#include <sys/types.h>
-#include <regex.h>
#include <string.h>
+#include <stdlib.h>
+#include <log/log.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_for(stmt) \
+ container_of(stmt, struct grub2_statement_for, st)
+#define to_stmt_conditional(stmt) \
+ container_of(stmt, struct grub2_statement_conditional, st)
struct env_entry {
+ char *name;
+ char *value;
+ struct list_item list;
+};
+
+struct grub2_symtab_entry {
const char *name;
- const char *value;
+ grub2_function fn;
+ void *data;
struct list_item list;
};
-static const char *env_lookup(struct grub2_script *script,
- const char *name, int name_len)
+static const char *default_prefix = "/boot/grub";
+
+static struct grub2_symtab_entry *script_lookup_function(
+ struct grub2_script *script, const char *name)
{
- struct env_entry *entry;
+ struct grub2_symtab_entry *entry;
+
+ list_for_each_entry(&script->symtab, entry, list) {
+ if (!strcmp(entry->name, name))
+ return entry;
+ }
+
+ return NULL;
+}
- printf("%s: %.*s\n", __func__, name_len, name);
+const char *script_env_get(struct grub2_script *script, const char *name)
+{
+ struct env_entry *entry;
list_for_each_entry(&script->environment, entry, list)
- if (!strncmp(entry->name, name, name_len)
- && entry->name[name_len] == '\0')
+ if (!strcmp(entry->name, name))
return entry->value;
return NULL;
}
-static bool expand_word(struct grub2_script *script, struct grub2_word *word)
+void script_env_set(struct grub2_script *script,
+ const char *name, const char *value)
{
- const char *val, *src;
- char *dest = NULL;
- regmatch_t match;
- int n, i;
+ struct env_entry *e, *entry = NULL;
- src = word->text;
+ list_for_each_entry(&script->environment, e, list) {
+ if (!strcmp(e->name, name)) {
+ entry = e;
+ break;
+ }
+ }
- n = regexec(&script->var_re, src, 1, &match, 0);
- printf("%s %s: %d\n", __func__, word->text, n);
- if (n != 0)
- return false;
+ if (!entry) {
+ entry = talloc(script, struct env_entry);
+ entry->name = talloc_strdup(entry, name);
+ list_add(&script->environment, &entry->list);
+ } else {
+ talloc_free(entry->value);
+ }
+
+ entry->value = talloc_strdup(entry, value);
+}
- i = 0;
- if (src[match.rm_so + 1] == '{')
- i++;
+static char *expand_var(struct grub2_script *script, struct grub2_word *word)
+{
+ const char *val;
- val = env_lookup(script, src + match.rm_so + 1 + i,
- match.rm_eo - match.rm_so - 1 - (i * 2));
+ val = script_env_get(script, word->name);
if (!val)
val = "";
- printf("repl: %s\n", val);
+ return talloc_strdup(script, val);
+}
+
+static bool is_delim(char c)
+{
+ return c == ' ' || c == '\t';
+}
+
+static bool option_is_default(struct grub2_script *script,
+ struct discover_boot_option *opt, const char *id)
+{
+ 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;
- dest = talloc_strndup(script, src, match.rm_so);
- dest = talloc_asprintf_append(dest, "%s%s", val, src + match.rm_eo);
+ /* if we don't have an explicit id for this option, fall back to
+ * the name */
+ if (!id)
+ id = opt->option->name;
- word->text = dest;
- return true;
+ return !strcmp(id, var);
}
-/* iterate through the words in an argv, looking for expansions. If a
- * word is marked with expand == true, then we process any variable
- * substitutions.
- *
- * Once that's done, we may (if split == true) have to split the word to create
- * new argv items
+static void append_text_to_current_arg(struct grub2_argv *argv,
+ const char *text, int len)
+{
+ char *cur = argv->argv[argv->argc - 1];
+
+ if (cur) {
+ int curlen = strlen(cur);
+ cur = talloc_realloc(argv->argv, cur, char, len + curlen + 1);
+ memcpy(cur + curlen, text, len);
+ cur[len + curlen] = '\0';
+
+ } else {
+ cur = talloc_strndup(argv->argv, text, len);
+ }
+
+ argv->argv[argv->argc-1] = cur;
+}
+
+/* Add a word to the argv array. Depending on the word type, and presence of
+ * delimiter characters, we may add multiple items to the array.
+ */
+static void append_word_to_argv(struct grub2_script *script,
+ struct grub2_argv *argv, struct grub2_word *word)
+{
+ const char *text, *pos;
+ int i, len;
+
+ /* If it's a variable, perform substitution */
+ if (word->type == GRUB2_WORD_VAR)
+ text = expand_var(script, word);
+ else
+ text = word->text;
+
+ len = strlen(text);
+
+ /* If we have no text, we leave the current word as-is. The caller
+ * has allocated an empty string for the case where this is the
+ * first text token */
+ if (!len)
+ return;
+
+ /* If we're not splitting, we just add the entire block to the
+ * current argv item */
+ if (!word->split) {
+ append_text_to_current_arg(argv, text, len);
+ return;
+ }
+
+ /* Scan for delimiters. If we find a word-end boundary, add the word
+ * to the argv array, and start a new argv item */
+ pos = !is_delim(text[0]) ? text : NULL;
+ for (i = 0; i < len; i++) {
+
+ /* first delimiter after a word: add the accumulated word to
+ * argv */
+ if (pos && is_delim(text[i])) {
+ append_text_to_current_arg(argv, pos,
+ text + i - pos);
+ pos = NULL;
+
+ /* first non-delimeter after a delimiter: record the starting
+ * position, and create another argv item */
+ } else if (!pos && !is_delim(text[i])) {
+ pos = text + i;
+ argv->argc++;
+ argv->argv = talloc_realloc(argv, argv->argv, char *,
+ argv->argc);
+ argv->argv[argv->argc - 1] = NULL;
+ }
+ }
+
+ /* add remaining word characters */
+ if (pos)
+ append_text_to_current_arg(argv, pos, text + len - pos);
+}
+
+/* Transform an argv word-token list (returned from the parser) into an
+ * expanded argv array (as used by the script execution code). We do this by
+ * iterating through the words in an argv_list, looking for GRUB2_WORD_VAR
+ * expansions.
*/
static void process_expansions(struct grub2_script *script,
struct grub2_argv *argv)
{
- struct grub2_word *word;
+ struct grub2_word *top_word, *word;
+
+ argv->argc = 0;
+ argv->argv = NULL;
- list_for_each_entry(&argv->words, word, argv_list) {
- if (!word->expand)
- continue;
+ list_for_each_entry(&argv->words, top_word, argv_list) {
+ argv->argc++;
+ argv->argv = talloc_realloc(argv, argv->argv, char *,
+ argv->argc);
+ /* because we've parsed a separate word here, we know that
+ * we need at least an empty string */
+ argv->argv[argv->argc - 1] = talloc_strdup(argv->argv, "");
- expand_word(script, word);
+ for (word = top_word; word; word = word->next)
+ append_word_to_argv(script, argv, word);
}
+
+ /* we may have allocated an extra argv element but not populated it */
+ if (!argv->argv[argv->argc - 1])
+ argv->argc--;
}
-int statements_execute(struct grub2_script *script,
+static int statements_execute(struct grub2_script *script,
struct grub2_statements *stmts)
{
struct grub2_statement *stmt;
struct grub2_statement *statement)
{
struct grub2_statement_simple *st = to_stmt_simple(statement);
+ struct grub2_symtab_entry *entry;
+ char *pos;
+ int rc;
if (!st->argv)
return 0;
process_expansions(script, st->argv);
- return 0;
+ if (!st->argv->argc)
+ return 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;
+ }
+
+ entry = script_lookup_function(script, st->argv->argv[0]);
+ if (!entry) {
+ pb_log("grub2: 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;
+}
- if (rc == 0)
- case_stmts = st->true_case;
+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 = false;
+ int rc = 0;
+
+ 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);
+
+ return rc;
+}
+
+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;
+ const char *id = NULL;
+ int i;
+
+ process_expansions(script, st->argv);
+
+ opt = discover_boot_option_create(script->ctx, script->ctx->device);
+
+ /* XXX: --options=values need to be parsed properly; this is a simple
+ * implementation to get --id= working.
+ */
+ for (i = 1; i < st->argv->argc; ++i) {
+ if (strncmp("--id=", st->argv->argv[i], 5) == 0) {
+ id = st->argv->argv[i] + 5;
+ break;
+ }
+ }
+ if (st->argv->argc > 0)
+ opt->option->name = talloc_strdup(opt, st->argv->argv[0]);
else
- case_stmts = st->false_case;
+ opt->option->name = talloc_strdup(opt, "(unknown)");
+
+ opt->option->id = talloc_asprintf(opt->option, "%s#%s",
+ script->ctx->device->device->id,
+ id ? id : opt->option->name);
+
+ script->opt = opt;
- if (case_stmts)
- statements_execute(script, case_stmts);
+ statements_execute(script, st->statements);
+
+ if (!opt->boot_image)
+ return -1;
+
+ opt->option->is_default = option_is_default(script, opt, id);
+
+ list_add_tail(&script->options, &opt->list);
+ 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)
+ name = expand_var(script, st->name);
else
- rc = 0;
+ name = st->name->text;
+
+ script_register_function(script, name, function_invoke, st);
+
+ return 0;
+}
+
+int statement_for_execute(struct grub2_script *script,
+ struct grub2_statement *statement)
+{
+ struct grub2_statement_for *st = to_stmt_for(statement);
+ const char *varname;
+ int i, rc = 0;
+
+ if (st->var->type == GRUB2_WORD_VAR)
+ expand_var(script, st->var);
+ varname = st->var->text;
+
+ process_expansions(script, st->list);
+
+ for (i = 0; i < st->list->argc; ++i) {
+ script_env_set(script, varname, st->list->argv[i]);
+ rc = statements_execute(script, st->body);
+ }
return rc;
}
static void init_env(struct grub2_script *script)
{
struct env_entry *env;
+ char *prefix, *sep;
list_init(&script->environment);
+ /* use location of the parsed config file to determine the prefix */
env = talloc(script, struct env_entry);
- env->name = talloc_strdup(env, "prefix");
- env->value = talloc_strdup(env, "/");
- list_add(&script->environment, &env->list);
-}
+ prefix = NULL;
+ if (script->filename) {
+ sep = strrchr(script->filename, '/');
+ if (sep)
+ prefix = talloc_strndup(env, script->filename,
+ sep - script->filename);
+ }
+ script_env_set(script, "prefix", prefix ? : default_prefix);
+ if (prefix)
+ talloc_free(prefix);
-void script_execute(struct grub2_script *script)
-{
- statements_execute(script, script->statements);
+ /* establish feature settings */
+ script_env_set(script, "feature_menuentry_id", "y");
}
-static int script_destroy(void *p)
+void script_register_function(struct grub2_script *script,
+ const char *name, grub2_function fn,
+ void *data)
{
- struct grub2_script *script = p;
- regfree(&script->var_re);
- return 0;
+ struct grub2_symtab_entry *entry;
+
+ entry = talloc(script, struct grub2_symtab_entry);
+ entry->fn = fn;
+ entry->name = name;
+ entry->data = data;
+ list_add(&script->symtab, &entry->list);
}
-struct grub2_script *create_script(void *ctx)
+static void set_fallback_default(struct grub2_script *script)
{
- struct grub2_script *script;
- int rc;
+ struct discover_boot_option *opt, *first = NULL;
+ bool have_default = false;
- script = talloc(ctx, struct grub2_script);
+ list_for_each_entry(&script->options, opt, list) {
+ if (!first)
+ first = opt;
+ have_default = have_default || opt->option->is_default;
+ }
+
+ if (!have_default && first) {
+ const char *env = script_env_get(script, "default");
- rc = regcomp(&script->var_re,
- "\\$\\{?([[:alpha:]][_[:alnum:]]*|[0-9]|[\\?@\\*#])\\}?",
- REG_EXTENDED);
- if (rc) {
- char err[200];
- regerror(rc, &script->var_re, err, sizeof(err));
- fprintf(stderr, "RE error %d: %s\n", rc, err);
- talloc_free(script);
- return NULL;
+ pb_log("grub: no explicit default (env default=%s), "
+ "falling back to first option (%s)\n",
+ env ?: "unset", first->option->name);
+ first->option->is_default = true;
}
- talloc_set_destructor(script, script_destroy);
+}
+
+void script_execute(struct grub2_script *script)
+{
+ struct discover_boot_option *opt, *tmp;
init_env(script);
+ statements_execute(script, script->statements);
+
+ set_fallback_default(script);
+
+ list_for_each_entry_safe(&script->options, opt, tmp, list)
+ discover_context_add_boot_option(script->ctx, opt);
+
+ /* Our option list will be invalid, as we've added all options to the
+ * discover context */
+ list_init(&script->options);
+}
+
+struct grub2_script *create_script(struct grub2_parser *parser,
+ struct discover_context *ctx)
+{
+ struct grub2_script *script;
+
+ script = talloc_zero(parser, struct grub2_script);
+
+ script->ctx = ctx;
+
+ list_init(&script->symtab);
+ list_init(&script->options);
+ register_builtins(script);
return script;
}
projects / petitboot / blobdiff