discover/grub2: Handle var tokens in lexer

[petitboot] / discover / grub2 / script.c

diff --git a/discover/grub2/script.c b/discover/grub2/script.c
index b6d3221c36effed793300a63af86d34a44475dfa..536139418d93b89457743bc35688bb03103e0fb6 100644 (file)
--- a/discover/grub2/script.c
+++ b/discover/grub2/script.c
@@ -1,6 +1,5 @@
 
 #include <sys/types.h>
-#include <regex.h>
 #include <string.h>
 
 #include <talloc/talloc.h>
@@ -19,50 +18,32 @@ struct env_entry {
 };
 
 static const char *env_lookup(struct grub2_script *script,
-               const char *name, int name_len)
+               const char *name)
 {
        struct env_entry *entry;
-       const char *str;
-
-       str = talloc_strndup(script, name, name_len);
-       printf("%s: %s\n", __func__, str);
 
        list_for_each_entry(&script->environment, entry, list)
-               if (!strncmp(entry->name, name, name_len))
+               if (!strcmp(entry->name, name))
                        return entry->value;
 
        return NULL;
 }
 
-static bool expand_word(struct grub2_script *script, struct grub2_word *word)
+static bool expand_var(struct grub2_script *script, struct grub2_word *word)
 {
-       const char *val, *src;
-       char *dest = NULL;
-       regmatch_t match;
-       int n;
-
-       src = word->text;
-
-       n = regexec(&script->var_re, src, 1, &match, 0);
-       printf("%s %s: %d\n", __func__, word->text, n);
-       if (n != 0)
-               return false;
+       const char *val;
 
-       val = env_lookup(script, src + match.rm_so,
-                                match.rm_eo - match.rm_so);
+       val = env_lookup(script, word->var.name);
        if (!val)
                val = "";
 
-       dest = talloc_strndup(script, src, match.rm_so);
-       dest = talloc_asprintf_append(dest, "%s%s", val, src + match.rm_eo);
+       word->type = GRUB2_WORD_TEXT;
+       word->text = talloc_strdup(script, val);
 
-       word->text = dest;
        return true;
 }
 
-/* iterate through the words in an argv, looking for expansions. If a
- * word is marked with expand == true, then we process any variable
- * substitutions.
+/* 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
@@ -70,13 +51,23 @@ static bool expand_word(struct grub2_script *script, struct grub2_word *word)
 static void process_expansions(struct grub2_script *script,
                struct grub2_argv *argv)
 {
-       struct grub2_word *word;
-
-       list_for_each_entry(&argv->words, word, argv_list) {
-               if (!word->expand)
-                       continue;
-
-               expand_word(script, word);
+       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;
        }
 }
 
@@ -89,7 +80,6 @@ int statements_execute(struct grub2_script *script,
        list_for_each_entry(&stmts->list, stmt, list) {
                if (stmt->exec)
                        rc = stmt->exec(script, stmt);
-               printf("%s(%p)\n", __func__, stmt);
        }
        return rc;
 }
@@ -129,40 +119,32 @@ int statement_if_execute(struct grub2_script *script,
        return rc;
 }
 
-
-void script_execute(struct grub2_script *script)
+static void init_env(struct grub2_script *script)
 {
-       statements_execute(script, script->statements);
+       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);
 }
 
-static int script_destroy(void *p)
+
+void script_execute(struct grub2_script *script)
 {
-       struct grub2_script *script = p;
-       regfree(&script->var_re);
-       return 0;
+       statements_execute(script, script->statements);
 }
 
 struct grub2_script *create_script(void *ctx)
 {
        struct grub2_script *script;
-       int rc;
 
        script = talloc(ctx, struct grub2_script);
 
-       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;
-
-       }
-       talloc_set_destructor(script, script_destroy);
-
-       list_init(&script->environment);
+       init_env(script);
 
        return script;
 }