misc/search.h

   1 /* Declarations for System V style searching functions.
   2    Copyright (C) 1995, 1996, 1997 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Library General Public License as
   7    published by the Free Software Foundation; either version 2 of the
   8    License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 02111-1307, USA.  */
  19
  20 #ifndef _SEARCH_H
  21 #define _SEARCH_H 1
  22
  23 #include <sys/cdefs.h>
  24
  25 #define __need_size_t
  26 #define __need_NULL
  27 #include <stddef.h>
  28
  29 __BEGIN_DECLS
  30
  31 #if defined(__USE_SVID) || defined(__USE_XOPEN_EXTENDED)
  32 /* Prototype structure for a linked-list data structure.
  33    This is the type used by the `insque' and `remque' functions.  */
  34
  35 struct qelem
  36   {
  37     struct qelem *q_forw;
  38     struct qelem *q_back;
  39     char q_data[1];
  40   };
  41
  42
  43 /* Insert ELEM into a doubly-linked list, after PREV.  */
  44 extern void insque __P ((void *__elem, void *__prev));
  45
  46 /* Unlink ELEM from the doubly-linked list that it is in.  */
  47 extern void remque __P ((void *__elem));
  48 #endif
  49
  50
  51 /* For use with hsearch(3).  */
  52 #ifndef __COMPAR_FN_T
  53 #define __COMPAR_FN_T
  54 typedef int (*__compar_fn_t) __P ((__const __ptr_t, __const __ptr_t));
  55 #endif
  56
  57 /* Action which shall be performed in the call the hsearch.  */
  58 typedef enum
  59   {
  60     FIND,
  61     ENTER
  62   }
  63 ACTION;
  64
  65 typedef struct entry
  66   {
  67     char *key;
  68     char *data;
  69   }
  70 ENTRY;
  71
  72 /* Opaque type for internal use.  */
  73 struct _ENTRY;
  74
  75 /* Data type for reentrant functions.  */
  76 struct hsearch_data
  77   {
  78     struct _ENTRY *table;
  79     unsigned int size;
  80     unsigned int filled;
  81   };
  82
  83 /* Family of hash table handling functions.  The functions also have
  84    reentrant counterparts ending with _r.  */
  85 extern ENTRY *hsearch __P ((ENTRY __item, ACTION __action));
  86 extern int hcreate __P ((size_t __nel));
  87 extern void hdestroy __P ((void));
  88
  89 extern int hsearch_r __P ((ENTRY __item, ACTION __action, ENTRY **__retval,
  90                            struct hsearch_data *__htab));
  91 extern int hcreate_r __P ((size_t __nel, struct hsearch_data *htab));
  92 extern void hdestroy_r __P ((struct hsearch_data *htab));
  93
  94
  95 /* The tsearch routines are very interesting. They make many
  96    assumptions about the compiler.  It assumes that the first field
  97    in node must be the "key" field, which points to the datum.
  98    Everything depends on that.  */
  99 /* For tsearch */
 100 typedef enum
 101 {
 102   preorder,
 103   postorder,
 104   endorder,
 105   leaf
 106 }
 107 VISIT;
 108
 109 /* Search for an entry matching the given KEY in the tree pointed to
 110    by *ROOTP and insert a new element if not found.  */
 111 extern void *tsearch __P ((__const void * __key, void **__rootp,
 112                            __compar_fn_t compar));
 113 extern void *__tsearch __P ((__const void * __key, void **__rootp,
 114                              __compar_fn_t compar));
 115
 116 /* Search for an entry matching the given KEY in the tree pointed to
 117    by *ROOTP.  If no matching entry is available return NULL.  */
 118 extern void *tfind __P ((__const void * __key, void *__const * __rootp,
 119                          __compar_fn_t compar));
 120 extern void *__tfind __P ((__const void * __key, void *__const * __rootp,
 121                            __compar_fn_t compar));
 122
 123 /* Remove the element matching KEY from the tree pointed to by *ROOTP.  */
 124 extern void *tdelete __P ((__const void * __key, void ** __rootp,
 125                            __compar_fn_t compar));
 126 extern void *__tdelete __P ((__const void * __key, void ** __rootp,
 127                              __compar_fn_t compar));
 128
 129 #ifndef __ACTION_FN_T
 130 #define __ACTION_FN_T
 131 typedef void (*__action_fn_t) __P ((__const void *__nodep,
 132                                     VISIT __value,
 133                                     int __level));
 134 #endif
 135
 136 /* Walk through the whole tree and call the ACTION callback for every node
 137    or leaf.  */
 138 extern void twalk __P ((__const void * __root, __action_fn_t action));
 139
 140 extern void __twalk __P ((__const void * __root, __action_fn_t action));
 141
 142 #ifdef __USE_GNU
 143 /* Callback type for function to free a tree node.  If the keys are atomic
 144    data this function should do nothing.  */
 145 typedef void (*__free_fn_t) __P ((void *__nodep));
 146
 147 /* Destroy the whole tree, call FREEFCT for each node or leaf.  */
 148 extern void __tdestroy __P ((void *__root, __free_fn_t freefct));
 149 extern void tdestroy __P ((void *__root, __free_fn_t freefct));
 150 #endif
 151
 152
 153 /* Perform linear search for KEY by comparing by COMPAR in an array
 154    [BASE,BASE+NMEMB*SIZE).  */
 155 extern void * lfind __P ((__const void *__key, __const void *__base,
 156                           size_t *__nmemb, size_t __size,
 157                           __compar_fn_t __compar));
 158
 159 /* Perform linear search for KEY by comparing by COMPAR function in
 160    array [BASE,BASE+NMEMB*SIZE) and insert entry if not found.  */
 161 extern void * lsearch __P ((__const void *__key, void *__base, size_t *__nmemb,
 162                             size_t __size, __compar_fn_t __compar));
 163
 164 __END_DECLS
 165
 166 #endif /* search.h */