1 files changed, 114 insertions, 0 deletions
diff --git a/include/search.h b/include/search.h
new file mode 100644
index 0000000..0469a85
--- /dev/null
+++ b/include/search.h
@@ -0,0 +1,114 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+/*
+ * Declarations for System V style searching functions.
+ * Copyright (C) 1995-1999, 2000 Free Software Foundation, Inc.
+ * This file is part of the GNU C Library.
+ */
+
+/*
+ * Based on code from uClibc-0.9.30.3
+ * Extensions for use within U-Boot
+ * Copyright (C) 2010-2013 Wolfgang Denk <wd@denx.de>
+ */
+
+#ifndef _SEARCH_H_
+#define _SEARCH_H_
+
+#include <env.h>
+#include <stddef.h>
+
+#define set_errno(val) do { errno = val; } while (0)
+
+/* enum env_action: action which shall be performed in the call to hsearch */
+enum env_action {
+	ENV_FIND,
+	ENV_ENTER,
+};
+
+/** struct env_entry - An entry in the environment hashtable */
+struct env_entry {
+	const char *key;
+	char *data;
+	int (*callback)(const char *name, const char *value, enum env_op op,
+		int flags);
+	int flags;
+};
+
+/*
+ * Family of hash table handling functions.  The functions also
+ * have reentrant counterparts ending with _r.  The non-reentrant
+ * functions all work on a single internal hash table.
+ */
+
+/* Data type for reentrant functions.  */
+struct hsearch_data {
+	struct env_entry_node *table;
+	unsigned int size;
+	unsigned int filled;
+/*
+ * Callback function which will check whether the given change for variable
+ * "item" to "newval" may be applied or not, and possibly apply such change.
+ * When (flag & H_FORCE) is set, it shall not print out any error message and
+ * shall force overwriting of write-once variables.
+ * Must return 0 for approval, 1 for denial.
+ */
+	int (*change_ok)(const struct env_entry *item, const char *newval,
+			 enum env_op, int flag);
+};
+
+/* Create a new hash table which will contain at most "nel" elements.  */
+int hcreate_r(size_t nel, struct hsearch_data *htab);
+
+/* Destroy current internal hash table.  */
+void hdestroy_r(struct hsearch_data *htab);
+
+/*
+ * Search for entry matching item.key in internal hash table.  If
+ * action is `ENV_FIND' return found entry or signal error by returning
+ * NULL.  If action is `ENV_ENTER' replace existing data (if any) with
+ * item.data.
+ * */
+int hsearch_r(struct env_entry item, enum env_action action,
+	      struct env_entry **retval, struct hsearch_data *htab, int flag);
+
+/*
+ * Search for an entry matching "match".  Otherwise, Same semantics
+ * as hsearch_r().
+ */
+int hmatch_r(const char *match, int last_idx, struct env_entry **retval,
+	     struct hsearch_data *htab);
+
+/* Search and delete entry matching "key" in internal hash table. */
+int hdelete_r(const char *key, struct hsearch_data *htab, int flag);
+
+ssize_t hexport_r(struct hsearch_data *htab, const char sep, int flag,
+		  char **resp, size_t size, int argc, char * const argv[]);
+
+/*
+ * nvars: length of vars array
+ * vars: array of strings (variable names) to import (nvars == 0 means all)
+ */
+int himport_r(struct hsearch_data *htab, const char *env, size_t size,
+	      const char sep, int flag, int crlf_is_lf, int nvars,
+	      char * const vars[]);
+
+/* Walk the whole table calling the callback on each element */
+int hwalk_r(struct hsearch_data *htab,
+	    int (*callback)(struct env_entry *entry));
+
+/* Flags for himport_r(), hexport_r(), hdelete_r(), and hsearch_r() */
+#define H_NOCLEAR	(1 << 0) /* do not clear hash table before importing */
+#define H_FORCE		(1 << 1) /* overwrite read-only/write-once variables */
+#define H_INTERACTIVE	(1 << 2) /* indicate that an import is user directed */
+#define H_HIDE_DOT	(1 << 3) /* don't print env vars that begin with '.' */
+#define H_MATCH_KEY	(1 << 4) /* search/grep key  = variable names	     */
+#define H_MATCH_DATA	(1 << 5) /* search/grep data = variable values	     */
+#define H_MATCH_BOTH	(H_MATCH_KEY | H_MATCH_DATA) /* search/grep both     */
+#define H_MATCH_IDENT	(1 << 6) /* search for indentical strings	     */
+#define H_MATCH_SUBSTR	(1 << 7) /* search for substring matches	     */
+#define H_MATCH_REGEX	(1 << 8) /* search for regular expression matches    */
+#define H_MATCH_METHOD	(H_MATCH_IDENT | H_MATCH_SUBSTR | H_MATCH_REGEX)
+#define H_PROGRAMMATIC	(1 << 9) /* indicate that an import is from env_set() */
+#define H_ORIGIN_FLAGS	(H_INTERACTIVE | H_PROGRAMMATIC)
+
+#endif /* _SEARCH_H_ */