--- /dev/null
+
+#define _GNU_SOURCE
+
+#include <assert.h>
+#include <string.h>
+
+#include <log/log.h>
+#include <talloc/talloc.h>
+#include <param_list/param_list.h>
+
+const char **common_known_params(void)
+{
+ static const char *common[] = {
+ "auto-boot?",
+ "petitboot,network",
+ "petitboot,timeout",
+ "petitboot,bootdevs",
+ "petitboot,language",
+ "petitboot,debug?",
+ "petitboot,write?",
+ "petitboot,snapshots?",
+ "petitboot,console",
+ "petitboot,http_proxy",
+ "petitboot,https_proxy",
+ NULL,
+ };
+
+ return common;
+}
+
+void param_list_init(struct param_list *pl, const char *known_params[])
+{
+ assert(known_params);
+ list_init(&pl->params);
+ pl->known_params = known_params;
+}
+
+bool param_list_is_known_n(const struct param_list *pl, const char *name,
+ unsigned int name_len)
+{
+ const char **known;
+
+ assert(pl->known_params);
+
+ param_list_for_each_known_param(pl, known) {
+ if (name_len == strlen(*known) && !strncmp(name, *known, name_len)) {
+ return true;
+ }
+ }
+
+ return false;
+}
+
+bool param_list_is_known(const struct param_list *pl, const char *name)
+{
+ const char **known;
+
+ assert(pl->known_params);
+
+ param_list_for_each_known_param(pl, known) {
+ if (!strcmp(name, *known)) {
+ return true;
+ }
+ }
+
+ return false;
+}
+
+struct param *param_list_get_param(struct param_list *pl, const char *name)
+{
+ struct param *param;
+
+ param_list_for_each(pl, param) {
+ if (!strcmp(param->name, name))
+ return param;
+ }
+ return NULL;
+}
+
+void param_list_set(struct param_list *pl, const char *name, const char *value,
+ bool modified_on_create)
+{
+ struct param *param;
+
+ param_list_for_each(pl, param) {
+ if (strcmp(param->name, name))
+ continue;
+
+ if (!strcmp(param->value, value))
+ return;
+
+ /* Update existing list entry. */
+ talloc_free(param->value);
+ param->value = talloc_strdup(param, value);
+ param->modified = true;
+ pb_debug_fn("Updated: %s:%s\n", name, value);
+ return;
+ }
+
+ /* Add new entry to list. */
+ param = talloc(pl, struct param);
+ param->modified = modified_on_create;
+ param->name = talloc_strdup(pl, name);
+ param->value = talloc_strdup(pl, value);
+ list_add(&pl->params, ¶m->list);
+ pb_debug_fn("Created: %s:%s\n", name, value);
+}
+
+void param_list_set_non_empty(struct param_list *pl, const char *name, const char *value,
+ bool modified_on_create)
+{
+ if (!param_list_get_value(pl, name) && !strlen(value)) {
+ return;
+ }
+
+ param_list_set(pl, name, value, modified_on_create);
+}
+
--- /dev/null
+#ifndef PARAM_LIST_H
+#define PARAM_LIST_H
+
+#include <stddef.h>
+
+#include <list/list.h>
+
+struct param {
+ char *name;
+ char *value;
+ bool modified;
+ struct list_item list;
+};
+
+struct param_list {
+ struct list params;
+ const char **known_params;
+};
+
+#define param_list_for_each(_pl_ptr, _pos) \
+ list_for_each_entry(&(_pl_ptr)->params, _pos, list)
+
+#define param_list_for_each_known_param(_pl_ptr, _pos) \
+ for (_pos = (_pl_ptr)->known_params; *_pos; _pos++)
+
+const char **common_known_params(void);
+
+void param_list_init(struct param_list *pl, const char *known_params[]);
+bool param_list_is_known(const struct param_list *pl, const char *name);
+bool param_list_is_known_n(const struct param_list *pl, const char *name,
+ unsigned int name_len);
+struct param *param_list_get_param(struct param_list *pl, const char *name);
+static inline const char *param_list_get_value(const struct param_list *pl,
+ const char *name)
+{
+ const struct param *param =
+ param_list_get_param((struct param_list *)pl, name);
+ return param ? param->value : NULL;
+}
+void param_list_set(struct param_list *pl, const char *name, const char *value,
+ bool modified_on_create);
+
+/* param_list_set_non_empty - Won't create a new parameter that would be empty. */
+void param_list_set_non_empty(struct param_list *pl, const char *name,
+ const char *value, bool modified_on_create);
+
+#endif /* PARAM_LIST_H */
+