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#include <sys/types.h>
#include <string.h>
#include <talloc/talloc.h>
#include "grub2.h"
#define to_stmt_simple(stmt) \
container_of(stmt, struct grub2_statement_simple, st)
#define to_stmt_if(stmt) \
container_of(stmt, struct grub2_statement_if, st)
struct env_entry {
const char *name;
const char *value;
struct list_item list;
};
static const char *env_lookup(struct grub2_script *script,
const char *name)
{
struct env_entry *entry;
list_for_each_entry(&script->environment, entry, list)
if (!strcmp(entry->name, name))
return entry->value;
return NULL;
}
static bool expand_var(struct grub2_script *script, struct grub2_word *word)
{
const char *val;
val = env_lookup(script, word->var.name);
if (!val)
val = "";
word->type = GRUB2_WORD_TEXT;
word->text = talloc_strdup(script, val);
return true;
}
/* iterate through the words in an argv, looking for GRUB2_WORD_VAR expansions.
*
* Once that's done, we may (if split == true) have to split the word to create
* new argv items
*/
static void process_expansions(struct grub2_script *script,
struct grub2_argv *argv)
{
struct grub2_word *top_word, *word;
list_for_each_entry(&argv->words, top_word, argv_list) {
/* expand vars and squash the list of words into the top struct.
* todo: splitting
*/
for (word = top_word; word; word = word->next) {
if (word->type == GRUB2_WORD_VAR)
expand_var(script, word);
if (word == top_word)
continue;
top_word->text = talloc_asprintf_append(top_word->text,
"%s", word->text);
}
top_word->next = NULL;
}
}
int statements_execute(struct grub2_script *script,
struct grub2_statements *stmts)
{
struct grub2_statement *stmt;
int rc = 0;
list_for_each_entry(&stmts->list, stmt, list) {
if (stmt->exec)
rc = stmt->exec(script, stmt);
}
return rc;
}
int statement_simple_execute(struct grub2_script *script,
struct grub2_statement *statement)
{
struct grub2_statement_simple *st = to_stmt_simple(statement);
if (!st->argv)
return 0;
process_expansions(script, st->argv);
return 0;
}
int statement_if_execute(struct grub2_script *script,
struct grub2_statement *statement)
{
struct grub2_statement_if *st = to_stmt_if(statement);
struct grub2_statements *case_stmts;
int rc;
rc = st->condition->exec(script, st->condition);
if (rc == 0)
case_stmts = st->true_case;
else
case_stmts = st->false_case;
if (case_stmts)
statements_execute(script, case_stmts);
else
rc = 0;
return rc;
}
static void init_env(struct grub2_script *script)
{
struct env_entry *env;
list_init(&script->environment);
env = talloc(script, struct env_entry);
env->name = talloc_strdup(env, "prefix");
env->value = talloc_strdup(env, "/");
list_add(&script->environment, &env->list);
}
void script_execute(struct grub2_script *script)
{
statements_execute(script, script->statements);
}
struct grub2_script *create_script(void *ctx)
{
struct grub2_script *script;
script = talloc(ctx, struct grub2_script);
init_env(script);
return script;
}
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