hash_method.c

00001 /*-
00002  * See the file LICENSE for redistribution information.
00003  *
00004  * Copyright (c) 1999, 2000
00005  * Sleepycat Software. All rights reserved.
00006  */
00007 
00008 #include "config.h"
00009 
00010 #ifndef lint
00011 static const char revid[] = "$Id: hash__method_8c-source.html,v 1.1 2008年06月08日 10:19:33 sebdiaz Exp $";
00012 #endif /* not lint */
00013 
00014 #ifndef NO_SYSTEM_INCLUDES
00015 #include <sys/types.h>
00016 #endif
00017 
00018 #include "db_int.h"
00019 #include "db_page.h"
00020 #include "hash.h"
00021 
00022 static int __ham_set_h_ffactor __P((DB *, u_int32_t));
00023 static int __ham_set_h_hash __P((DB *, u_int32_t(*)(const void *, u_int32_t)));
00024 static int __ham_set_h_nelem __P((DB *, u_int32_t));
00025 
00026 /*
00027  * CDB___ham_db_create --
00028  * Hash specific initialization of the DB structure.
00029  *
00030  * PUBLIC: int CDB___ham_db_create __P((DB *));
00031  */
00032 int
00033 CDB___ham_db_create(dbp)
00034 DB *dbp;
00035 {
00036 HASH *hashp;
00037 int ret;
00038 
00039 if ((ret = CDB___os_malloc(dbp->dbenv,
00040 sizeof(HASH), NULL, &dbp->h_internal)) != 0)
00041 return (ret);
00042 
00043 hashp = dbp->h_internal;
00044 
00045 hashp->h_nelem = 0; /* Defaults. */
00046 hashp->h_ffactor = 0;
00047 hashp->h_hash = NULL;
00048 
00049 dbp->set_h_ffactor = __ham_set_h_ffactor;
00050 dbp->set_h_hash = __ham_set_h_hash;
00051 dbp->set_h_nelem = __ham_set_h_nelem;
00052 
00053 return (0);
00054 }
00055 
00056 /*
00057  * PUBLIC: int CDB___ham_db_close __P((DB *));
00058  */
00059 int
00060 CDB___ham_db_close(dbp)
00061 DB *dbp;
00062 {
00063 if (dbp->h_internal == NULL)
00064 return (0);
00065 CDB___os_free(dbp->h_internal, sizeof(HASH));
00066 dbp->h_internal = NULL;
00067 return (0);
00068 }
00069 
00070 /*
00071  * __ham_set_h_ffactor --
00072  * Set the fill factor.
00073  */
00074 static int
00075 __ham_set_h_ffactor(dbp, h_ffactor)
00076 DB *dbp;
00077 u_int32_t h_ffactor;
00078 {
00079 HASH *hashp;
00080 
00081 DB_ILLEGAL_AFTER_OPEN(dbp, "set_h_ffactor");
00082 DB_ILLEGAL_METHOD(dbp, DB_OK_HASH);
00083 
00084 hashp = dbp->h_internal;
00085 hashp->h_ffactor = h_ffactor;
00086 return (0);
00087 }
00088 
00089 /*
00090  * __ham_set_h_hash --
00091  * Set the hash function.
00092  */
00093 static int
00094 __ham_set_h_hash(dbp, func)
00095 DB *dbp;
00096 u_int32_t (*func) __P((const void *, u_int32_t));
00097 {
00098 HASH *hashp;
00099 
00100 DB_ILLEGAL_AFTER_OPEN(dbp, "set_h_hash");
00101 DB_ILLEGAL_METHOD(dbp, DB_OK_HASH);
00102 
00103 hashp = dbp->h_internal;
00104 hashp->h_hash = func;
00105 return (0);
00106 }
00107 
00108 /*
00109  * __ham_set_h_nelem --
00110  * Set the table size.
00111  */
00112 static int
00113 __ham_set_h_nelem(dbp, h_nelem)
00114 DB *dbp;
00115 u_int32_t h_nelem;
00116 {
00117 HASH *hashp;
00118 
00119 DB_ILLEGAL_AFTER_OPEN(dbp, "set_h_nelem");
00120 DB_ILLEGAL_METHOD(dbp, DB_OK_HASH);
00121 
00122 hashp = dbp->h_internal;
00123 hashp->h_nelem = h_nelem;
00124 return (0);
00125 }