/* 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 */ #ifndef _SEARCH_H_ #define _SEARCH_H_ #include #include #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; #ifndef CONFIG_SPL_BUILD int (*callback)(const char *name, const char *value, enum env_op op, int flags); #endif 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); /** * hdelete_r() - Search and delete entry in internal hash table * * @key: Name of entry to delete * @htab: Hash table * @flag: Flags to use (H_...) * Return: 0 on success, -ENOENT if not found, -EPERM if the hash table callback * rejected changing the variable, -EINVAL if the hash table refused to * delete the variable */ 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) #define H_DEFAULT (1 << 10) /* indicate that an import is default env */ #define H_EXTERNAL (1 << 11) /* indicate that an import is external env */ #endif /* _SEARCH_H_ */