1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
|
/*
** $Id: lstring.c,v 1.63 2001/06/06 18:00:19 roberto Exp roberto $
** String table (keeps all strings handled by Lua)
** See Copyright Notice in lua.h
*/
#include <string.h>
#define LUA_PRIVATE
#include "lua.h"
#include "lmem.h"
#include "lobject.h"
#include "lstate.h"
#include "lstring.h"
void luaS_freeall (lua_State *L) {
lua_assert(G(L)->strt.nuse==0);
luaM_freearray(L, G(L)->strt.hash, G(L)->strt.size, TString *);
}
void luaS_resize (lua_State *L, int newsize) {
TString **newhash = luaM_newvector(L, newsize, TString *);
stringtable *tb = &G(L)->strt;
int i;
for (i=0; i<newsize; i++) newhash[i] = NULL;
/* rehash */
for (i=0; i<tb->size; i++) {
TString *p = tb->hash[i];
while (p) { /* for each node in the list */
TString *next = p->nexthash; /* save next */
lu_hash h = p->hash;
int h1 = lmod(h, newsize); /* new position */
lua_assert((int)(h%newsize) == lmod(h, newsize));
p->nexthash = newhash[h1]; /* chain it in new position */
newhash[h1] = p;
p = next;
}
}
luaM_freearray(L, tb->hash, tb->size, TString *);
tb->size = newsize;
tb->hash = newhash;
}
static TString *newlstr (lua_State *L, const l_char *str, size_t l, lu_hash h) {
TString *ts = (TString *)luaM_malloc(L, sizestring(l));
stringtable *tb;
ts->nexthash = NULL;
ts->len = l;
ts->hash = h;
ts->marked = 0;
ts->constindex = 0;
memcpy(getstr(ts), str, l*sizeof(l_char));
getstr(ts)[l] = l_c('\0'); /* ending 0 */
tb = &G(L)->strt;
h = lmod(h, tb->size);
ts->nexthash = tb->hash[h]; /* chain new entry */
tb->hash[h] = ts;
tb->nuse++;
if (tb->nuse > (ls_nstr)tb->size && tb->size <= MAX_INT/2)
luaS_resize(L, tb->size*2); /* too crowded */
return ts;
}
TString *luaS_newlstr (lua_State *L, const l_char *str, size_t l) {
TString *ts;
lu_hash h = l; /* seed */
size_t step = (l>>5)+1; /* if string is too long, don't hash all its chars */
size_t l1;
for (l1=l; l1>=step; l1-=step) /* compute hash */
h = h ^ ((h<<5)+(h>>2)+uchar(str[l1-1]));
for (ts = G(L)->strt.hash[lmod(h, G(L)->strt.size)]; ts; ts = ts->nexthash) {
if (ts->len == l && (memcmp(str, getstr(ts), l) == 0))
return ts;
}
return newlstr(L, str, l, h); /* not found */
}
Udata *luaS_newudata (lua_State *L, size_t s) {
Udata *u = (Udata *)luaM_malloc(L, sizeudata(s));
u->len = s;
u->tag = 0;
u->value = ((union L_UUdata *)(u) + 1);
/* chain it on udata list */
u->next = G(L)->rootudata;
G(L)->rootudata = u;
return u;
}
|
