1 /* SPDX-License-Identifier: LGPL-2.1+ */ 2 /* 3 * Declarations for System V style searching functions. 4 * Copyright (C) 1995-1999, 2000 Free Software Foundation, Inc. 5 * This file is part of the GNU C Library. 6 */ 7 8 /* 9 * Based on code from uClibc-0.9.30.3 10 * Extensions for use within U-Boot 11 * Copyright (C) 2010-2013 Wolfgang Denk <wd (at) denx.de> 12 */ 13 14 #ifndef _SEARCH_H_ 15 #define _SEARCH_H_ 16 17 #include <stddef.h> 18 19 #define __set_errno(val) do { errno = val; } while (0) 20 21 enum env_op { 22 env_op_create, 23 env_op_delete, 24 env_op_overwrite, 25 }; 26 27 /* Action which shall be performed in the call to hsearch. */ 28 typedef enum { 29 FIND, 30 ENTER 31 } ACTION; 32 33 typedef struct entry { 34 const char *key; 35 char *data; 36 int (*callback)(const char *name, const char *value, enum env_op op, 37 int flags); 38 int flags; 39 } ENTRY; 40 41 /* Opaque type for internal use. */ 42 struct _ENTRY; 43 44 /* 45 * Family of hash table handling functions. The functions also 46 * have reentrant counterparts ending with _r. The non-reentrant 47 * functions all work on a single internal hash table. 48 */ 49 50 /* Data type for reentrant functions. */ 51 struct hsearch_data { 52 struct _ENTRY *table; 53 unsigned int size; 54 unsigned int filled; 55 /* 56 * Callback function which will check whether the given change for variable 57 * "__item" to "newval" may be applied or not, and possibly apply such change. 58 * When (flag & H_FORCE) is set, it shall not print out any error message and 59 * shall force overwriting of write-once variables. 60 * Must return 0 for approval, 1 for denial. 61 */ 62 int (*change_ok)(const ENTRY *__item, const char *newval, enum env_op, 63 int flag); 64 }; 65 66 /* Create a new hash table which will contain at most "__nel" elements. */ 67 extern int hcreate_r(size_t __nel, struct hsearch_data *__htab); 68 69 /* Destroy current internal hash table. */ 70 extern void hdestroy_r(struct hsearch_data *__htab); 71 72 /* 73 * Search for entry matching __item.key in internal hash table. If 74 * ACTION is `FIND' return found entry or signal error by returning 75 * NULL. If ACTION is `ENTER' replace existing data (if any) with 76 * __item.data. 77 * */ 78 extern int hsearch_r(ENTRY __item, ACTION __action, ENTRY ** __retval, 79 struct hsearch_data *__htab, int __flag); 80 81 /* 82 * Search for an entry matching "__match". Otherwise, Same semantics 83 * as hsearch_r(). 84 */ 85 extern int hmatch_r(const char *__match, int __last_idx, ENTRY ** __retval, 86 struct hsearch_data *__htab); 87 88 /* Search and delete entry matching "__key" in internal hash table. */ 89 extern int hdelete_r(const char *__key, struct hsearch_data *__htab, 90 int __flag); 91 92 extern ssize_t hexport_r(struct hsearch_data *__htab, 93 const char __sep, int __flag, char **__resp, size_t __size, 94 int argc, char * const argv[]); 95 96 /* 97 * nvars: length of vars array 98 * vars: array of strings (variable names) to import (nvars == 0 means all) 99 */ 100 extern int himport_r(struct hsearch_data *__htab, 101 const char *__env, size_t __size, const char __sep, 102 int __flag, int __crlf_is_lf, int nvars, 103 char * const vars[]); 104 105 /* Walk the whole table calling the callback on each element */ 106 extern int hwalk_r(struct hsearch_data *__htab, int (*callback)(ENTRY *)); 107 108 /* Flags for himport_r(), hexport_r(), hdelete_r(), and hsearch_r() */ 109 #define H_NOCLEAR (1 << 0) /* do not clear hash table before importing */ 110 #define H_FORCE (1 << 1) /* overwrite read-only/write-once variables */ 111 #define H_INTERACTIVE (1 << 2) /* indicate that an import is user directed */ 112 #define H_HIDE_DOT (1 << 3) /* don't print env vars that begin with '.' */ 113 #define H_MATCH_KEY (1 << 4) /* search/grep key = variable names */ 114 #define H_MATCH_DATA (1 << 5) /* search/grep data = variable values */ 115 #define H_MATCH_BOTH (H_MATCH_KEY | H_MATCH_DATA) /* search/grep both */ 116 #define H_MATCH_IDENT (1 << 6) /* search for indentical strings */ 117 #define H_MATCH_SUBSTR (1 << 7) /* search for substring matches */ 118 #define H_MATCH_REGEX (1 << 8) /* search for regular expression matches */ 119 #define H_MATCH_METHOD (H_MATCH_IDENT | H_MATCH_SUBSTR | H_MATCH_REGEX) 120 #define H_PROGRAMMATIC (1 << 9) /* indicate that an import is from env_set() */ 121 #define H_ORIGIN_FLAGS (H_INTERACTIVE | H_PROGRAMMATIC) 122 123 #endif /* _SEARCH_H_ */ 124
