1 /*********************************************************************** 2 * * 3 * This software is part of the ast package * 4 * Copyright (c) 1985-2007 AT&T Knowledge Ventures * 5 * and is licensed under the * 6 * Common Public License, Version 1.0 * 7 * by AT&T Knowledge Ventures * 8 * * 9 * A copy of the License is available at * 10 * http://www.opensource.org/licenses/cpl1.0.txt * 11 * (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) * 12 * * 13 * Information and Software Systems Research * 14 * AT&T Research * 15 * Florham Park NJ * 16 * * 17 * Glenn Fowler <gsf@research.att.com> * 18 * David Korn <dgk@research.att.com> * 19 * Phong Vo <kpv@research.att.com> * 20 * * 21 ***********************************************************************/ 22 /* 23 * hsearch() for systems that have <search.h> but no hsearch() 24 * why would such a system provide the interface but not the 25 * implementation? that's what happens when one slimes their 26 * way through standards compliance 27 * 28 * NOTE: please excuse the crude feature test 29 */ 30 31 #if !_UWIN 32 33 void _STUB_hsearch(){} 34 35 #else 36 37 #if _PACKAGE_ast 38 #include <ast.h> 39 #endif 40 41 #define hcreate ______hcreate 42 #define hdestroy ______hdestroy 43 #define hsearch ______hsearch 44 45 #include <search.h> 46 47 #undef hcreate 48 #undef hdestroy 49 #undef hsearch 50 51 #include "dthdr.h" 52 53 #if defined(__EXPORT__) 54 #define extern __EXPORT__ 55 #endif 56 57 /* POSIX hsearch library based on libdt 58 ** Written by Kiem-Phong Vo (AT&T Research, 07/19/95) 59 */ 60 61 /* type of objects in hash table */ 62 typedef struct _hash_s 63 { Dtlink_t link; 64 ENTRY item; 65 } Hash_t; 66 67 /* object delete function */ 68 #if __STD_C 69 static void hashfree(Dt_t* dt, Void_t* obj, Dtdisc_t* disc) 70 #else 71 static void hashfree(dt, obj, disc) 72 Dt_t* dt; 73 Void_t* obj; 74 Dtdisc_t* disc; 75 #endif 76 { 77 free(((Hash_t*)obj)->item.key); 78 free(obj); 79 } 80 81 static Dt_t* Hashtab; /* object dictionary */ 82 static Dtdisc_t Hashdisc = /* discipline */ 83 { sizeof(Dtlink_t), -1, 84 0, 85 NIL(Dtmake_f), hashfree, 86 NIL(Dtcompar_f), /* always use strcmp */ 87 NIL(Dthash_f), 88 NIL(Dtmemory_f), 89 NIL(Dtevent_f) 90 }; 91 92 extern 93 #if __STD_C 94 int hcreate(size_t nel) 95 #else 96 int hcreate(nel) 97 size_t nel; 98 #endif 99 { 100 if(Hashtab) /* already opened */ 101 return 0; 102 103 if(!(Hashtab = dtopen(&Hashdisc,Dtset)) ) 104 return 0; 105 106 return 1; 107 } 108 109 extern void hdestroy() 110 { if(Hashtab) 111 dtclose(Hashtab); 112 Hashtab = NIL(Dt_t*); 113 } 114 115 extern 116 #if __STD_C 117 ENTRY* hsearch(ENTRY item, ACTION action) 118 #else 119 ENTRY* hsearch(item, action) 120 ENTRY item; 121 ACTION action; 122 #endif 123 { 124 reg Hash_t* o; 125 126 if(!Hashtab) 127 return NIL(ENTRY*); 128 129 if(!(o = (Hash_t*)dtmatch(Hashtab,item.key)) && action == ENTER && 130 (o = (Hash_t*)malloc(sizeof(Hash_t)) ) ) 131 { o->item = item; 132 o = (Hash_t*)dtinsert(Hashtab,o); 133 } 134 135 return o ? &(o->item) : NIL(ENTRY*); 136 } 137 138 #endif 139