Commit | Line | Data |
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8665f9e4 | 1 | /* hash.c |
a687059c | 2 | * |
4bb101f2 | 3 | * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1999, 2000, 2001, 2002, |
8665f9e4 | 4 | * 2005 by Larry Wall and others |
a687059c | 5 | * |
352d5a3a LW |
6 | * You may distribute under the terms of either the GNU General Public |
7 | * License or the Artistic License, as specified in the README file. | |
8d063cd8 LW |
8 | */ |
9 | ||
10 | #include <stdio.h> | |
11 | #include "EXTERN.h" | |
8d063cd8 | 12 | #include "a2p.h" |
9c8d0b29 | 13 | #include "util.h" |
8d063cd8 | 14 | |
011f1a1a JH |
15 | #ifdef NETWARE |
16 | char *savestr(char *str); | |
17 | #endif | |
18 | ||
8d063cd8 | 19 | STR * |
f0f333f4 | 20 | hfetch(register HASH *tb, char *key) |
8d063cd8 LW |
21 | { |
22 | register char *s; | |
23 | register int i; | |
24 | register int hash; | |
25 | register HENT *entry; | |
26 | ||
27 | if (!tb) | |
28 | return Nullstr; | |
29 | for (s=key, i=0, hash = 0; | |
30 | /* while */ *s; | |
31 | s++, i++, hash *= 5) { | |
32 | hash += *s * coeff[i]; | |
33 | } | |
34 | entry = tb->tbl_array[hash & tb->tbl_max]; | |
35 | for (; entry; entry = entry->hent_next) { | |
36 | if (entry->hent_hash != hash) /* strings can't be equal */ | |
37 | continue; | |
38 | if (strNE(entry->hent_key,key)) /* is this it? */ | |
39 | continue; | |
40 | return entry->hent_val; | |
41 | } | |
42 | return Nullstr; | |
43 | } | |
44 | ||
45 | bool | |
f0f333f4 | 46 | hstore(register HASH *tb, char *key, STR *val) |
8d063cd8 LW |
47 | { |
48 | register char *s; | |
49 | register int i; | |
50 | register int hash; | |
51 | register HENT *entry; | |
52 | register HENT **oentry; | |
53 | ||
54 | if (!tb) | |
55 | return FALSE; | |
56 | for (s=key, i=0, hash = 0; | |
57 | /* while */ *s; | |
58 | s++, i++, hash *= 5) { | |
59 | hash += *s * coeff[i]; | |
60 | } | |
61 | ||
62 | oentry = &(tb->tbl_array[hash & tb->tbl_max]); | |
63 | i = 1; | |
64 | ||
65 | for (entry = *oentry; entry; i=0, entry = entry->hent_next) { | |
66 | if (entry->hent_hash != hash) /* strings can't be equal */ | |
67 | continue; | |
68 | if (strNE(entry->hent_key,key)) /* is this it? */ | |
69 | continue; | |
fe14fcc3 | 70 | /*NOSTRICT*/ |
8c52afec | 71 | safefree(entry->hent_val); |
8d063cd8 LW |
72 | entry->hent_val = val; |
73 | return TRUE; | |
74 | } | |
fe14fcc3 | 75 | /*NOSTRICT*/ |
8d063cd8 LW |
76 | entry = (HENT*) safemalloc(sizeof(HENT)); |
77 | ||
78 | entry->hent_key = savestr(key); | |
79 | entry->hent_val = val; | |
80 | entry->hent_hash = hash; | |
81 | entry->hent_next = *oentry; | |
82 | *oentry = entry; | |
83 | ||
84 | if (i) { /* initial entry? */ | |
85 | tb->tbl_fill++; | |
86 | if ((tb->tbl_fill * 100 / (tb->tbl_max + 1)) > FILLPCT) | |
87 | hsplit(tb); | |
88 | } | |
89 | ||
90 | return FALSE; | |
91 | } | |
92 | ||
9c8d0b29 | 93 | void |
f0f333f4 | 94 | hsplit(HASH *tb) |
8d063cd8 | 95 | { |
8665f9e4 | 96 | const int oldsize = tb->tbl_max + 1; |
8d063cd8 LW |
97 | register int newsize = oldsize * 2; |
98 | register int i; | |
99 | register HENT **a; | |
100 | register HENT **b; | |
101 | register HENT *entry; | |
102 | register HENT **oentry; | |
103 | ||
104 | a = (HENT**) saferealloc((char*)tb->tbl_array, newsize * sizeof(HENT*)); | |
948ed65c | 105 | memset(&a[oldsize], 0, oldsize * sizeof(HENT*)); /* zero second half */ |
8d063cd8 LW |
106 | tb->tbl_max = --newsize; |
107 | tb->tbl_array = a; | |
108 | ||
109 | for (i=0; i<oldsize; i++,a++) { | |
110 | if (!*a) /* non-existent */ | |
111 | continue; | |
112 | b = a+oldsize; | |
113 | for (oentry = a, entry = *a; entry; entry = *oentry) { | |
114 | if ((entry->hent_hash & newsize) != i) { | |
115 | *oentry = entry->hent_next; | |
116 | entry->hent_next = *b; | |
117 | if (!*b) | |
118 | tb->tbl_fill++; | |
119 | *b = entry; | |
120 | continue; | |
121 | } | |
122 | else | |
123 | oentry = &entry->hent_next; | |
124 | } | |
125 | if (!*a) /* everything moved */ | |
126 | tb->tbl_fill--; | |
127 | } | |
128 | } | |
129 | ||
130 | HASH * | |
f0f333f4 | 131 | hnew(void) |
8d063cd8 LW |
132 | { |
133 | register HASH *tb = (HASH*)safemalloc(sizeof(HASH)); | |
134 | ||
135 | tb->tbl_array = (HENT**) safemalloc(8 * sizeof(HENT*)); | |
136 | tb->tbl_fill = 0; | |
137 | tb->tbl_max = 7; | |
138 | hiterinit(tb); /* so each() will start off right */ | |
948ed65c | 139 | memset(tb->tbl_array, 0, 8 * sizeof(HENT*)); |
8d063cd8 LW |
140 | return tb; |
141 | } | |
142 | ||
9c8d0b29 | 143 | int |
f0f333f4 | 144 | hiterinit(register HASH *tb) |
8d063cd8 LW |
145 | { |
146 | tb->tbl_riter = -1; | |
147 | tb->tbl_eiter = Null(HENT*); | |
148 | return tb->tbl_fill; | |
149 | } |