+static char *field_append(struct bls_state *state, int type, char *buffer,
+ char *start, char *end)
+{
+ char *temp = talloc_strndup(state, start, end - start + 1);
+ const char *field = temp;
+
+ if (type == GRUB2_WORD_VAR) {
+ field = script_env_get(state->script, temp);
+ if (!field)
+ return buffer;
+ }
+
+ if (!buffer)
+ buffer = talloc_strdup(state->opt, field);
+ else
+ buffer = talloc_asprintf_append(buffer, "%s", field);
+
+ return buffer;
+}
+
+static char *expand_field(struct bls_state *state, char *value)
+{
+ char *buffer = NULL;
+ char *start = value;
+ char *end = value;
+ int type = GRUB2_WORD_TEXT;
+
+ while (*value) {
+ if (*value == '$') {
+ if (start != end) {
+ buffer = field_append(state, type, buffer,
+ start, end);
+ if (!buffer)
+ return NULL;
+ }
+
+ type = GRUB2_WORD_VAR;
+ start = value + 1;
+ } else if (type == GRUB2_WORD_VAR) {
+ if (!isalnum(*value) && *value != '_') {
+ buffer = field_append(state, type, buffer,
+ start, end);
+ type = GRUB2_WORD_TEXT;
+ start = value;
+ }
+ }
+
+ end = value;
+ value++;
+ }
+
+ if (start != end) {
+ buffer = field_append(state, type, buffer,
+ start, end);
+ if (!buffer)
+ return NULL;
+ }
+
+ return buffer;
+}
+