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-rw-r--r--ltable.c128
1 files changed, 71 insertions, 57 deletions
diff --git a/ltable.c b/ltable.c
index 1895029c..ba1ccbe8 100644
--- a/ltable.c
+++ b/ltable.c
@@ -1,5 +1,5 @@
1/* 1/*
2** $Id: ltable.c,v 1.61 2000/12/22 16:57:46 roberto Exp roberto $ 2** $Id: ltable.c,v 1.62 2000/12/28 12:55:41 roberto Exp roberto $
3** Lua tables (hash) 3** Lua tables (hash)
4** See Copyright Notice in lua.h 4** See Copyright Notice in lua.h
5*/ 5*/
@@ -23,7 +23,6 @@
23#include "lmem.h" 23#include "lmem.h"
24#include "lobject.h" 24#include "lobject.h"
25#include "lstate.h" 25#include "lstate.h"
26#include "lstring.h"
27#include "ltable.h" 26#include "ltable.h"
28 27
29 28
@@ -31,6 +30,9 @@
31#define TagDefault LUA_TTABLE 30#define TagDefault LUA_TTABLE
32 31
33 32
33#define hashnum(t,n) (&t->node[(luint32)(lint32)(n)&(t->size-1)])
34#define hashstr(t,str) (&t->node[(str)->u.s.hash&(t->size-1)])
35
34 36
35/* 37/*
36** returns the `main' position of an element in a table (that is, the index 38** returns the `main' position of an element in a table (that is, the index
@@ -40,11 +42,9 @@ Node *luaH_mainposition (const Hash *t, const TObject *key) {
40 luint32 h; 42 luint32 h;
41 switch (ttype(key)) { 43 switch (ttype(key)) {
42 case LUA_TNUMBER: 44 case LUA_TNUMBER:
43 h = (luint32)(lint32)nvalue(key); 45 return hashnum(t, nvalue(key));
44 break;
45 case LUA_TSTRING: 46 case LUA_TSTRING:
46 h = tsvalue(key)->u.s.hash; 47 return hashstr(t, tsvalue(key));
47 break;
48 case LUA_TUSERDATA: 48 case LUA_TUSERDATA:
49 h = IntPoint(tsvalue(key)); 49 h = IntPoint(tsvalue(key));
50 break; 50 break;
@@ -57,31 +57,26 @@ Node *luaH_mainposition (const Hash *t, const TObject *key) {
57 default: 57 default:
58 return NULL; /* invalid key */ 58 return NULL; /* invalid key */
59 } 59 }
60 LUA_ASSERT(h%(unsigned int)t->size == (h&((unsigned int)t->size-1)),
61 "a&(x-1) == a%x, for x power of 2");
62 return &t->node[h&(t->size-1)]; 60 return &t->node[h&(t->size-1)];
63} 61}
64 62
65 63
66static const TObject *luaH_getany (lua_State *L, const Hash *t, 64static const TObject *luaH_getany (const Hash *t, const TObject *key) {
67 const TObject *key) {
68 Node *n = luaH_mainposition(t, key); 65 Node *n = luaH_mainposition(t, key);
69 if (!n) 66 while (n) {
70 lua_error(L, "table index is nil");
71 else do {
72 if (luaO_equalObj(key, &n->key)) 67 if (luaO_equalObj(key, &n->key))
73 return &n->val; 68 return &n->val;
74 n = n->next; 69 n = n->next;
75 } while (n); 70 }
76 return &luaO_nilobject; /* key not found */ 71 return &luaO_nilobject; /* key not found */
77} 72}
78 73
79 74
80/* specialized version for numbers */ 75/* specialized version for numbers */
81const TObject *luaH_getnum (const Hash *t, lua_Number key) { 76const TObject *luaH_getnum (const Hash *t, lua_Number key) {
82 Node *n = &t->node[(luint32)(lint32)key&(t->size-1)]; 77 Node *n = hashnum(t, key);
83 do { 78 do {
84 if (ttype(&n->key) == LUA_TNUMBER && nvalue(&n->key) == key) 79 if (nvalue(&n->key) == key && ttype(&n->key) == LUA_TNUMBER)
85 return &n->val; 80 return &n->val;
86 n = n->next; 81 n = n->next;
87 } while (n); 82 } while (n);
@@ -91,9 +86,9 @@ const TObject *luaH_getnum (const Hash *t, lua_Number key) {
91 86
92/* specialized version for strings */ 87/* specialized version for strings */
93const TObject *luaH_getstr (const Hash *t, TString *key) { 88const TObject *luaH_getstr (const Hash *t, TString *key) {
94 Node *n = &t->node[key->u.s.hash&(t->size-1)]; 89 Node *n = hashstr(t, key);
95 do { 90 do {
96 if (ttype(&n->key) == LUA_TSTRING && tsvalue(&n->key) == key) 91 if (tsvalue(&n->key) == key && ttype(&n->key) == LUA_TSTRING)
97 return &n->val; 92 return &n->val;
98 n = n->next; 93 n = n->next;
99 } while (n); 94 } while (n);
@@ -101,11 +96,11 @@ const TObject *luaH_getstr (const Hash *t, TString *key) {
101} 96}
102 97
103 98
104const TObject *luaH_get (lua_State *L, const Hash *t, const TObject *key) { 99const TObject *luaH_get (const Hash *t, const TObject *key) {
105 switch (ttype(key)) { 100 switch (ttype(key)) {
106 case LUA_TNUMBER: return luaH_getnum(t, nvalue(key)); 101 case LUA_TNUMBER: return luaH_getnum(t, nvalue(key));
107 case LUA_TSTRING: return luaH_getstr(t, tsvalue(key)); 102 case LUA_TSTRING: return luaH_getstr(t, tsvalue(key));
108 default: return luaH_getany(L, t, key); 103 default: return luaH_getany(t, key);
109 } 104 }
110} 105}
111 106
@@ -115,7 +110,7 @@ Node *luaH_next (lua_State *L, const Hash *t, const TObject *key) {
115 if (ttype(key) == LUA_TNIL) 110 if (ttype(key) == LUA_TNIL)
116 i = 0; /* first iteration */ 111 i = 0; /* first iteration */
117 else { 112 else {
118 const TObject *v = luaH_get(L, t, key); 113 const TObject *v = luaH_get(t, key);
119 if (v == &luaO_nilobject) 114 if (v == &luaO_nilobject)
120 lua_error(L, "invalid key for `next'"); 115 lua_error(L, "invalid key for `next'");
121 i = (int)(((const char *)v - 116 i = (int)(((const char *)v -
@@ -224,30 +219,17 @@ static void rehash (lua_State *L, Hash *t) {
224 219
225 220
226/* 221/*
227** inserts a key into a hash table; first, check whether key is 222** inserts a new key into a hash table; first, check whether key's main
228** already present; if not, check whether key's main position is free; 223** position is free; if not, check whether colliding node is in its main
229** if not, check whether colliding node is in its main position or not; 224** position or not; if it is not, move colliding node to an empty place and
230** if it is not, move colliding node to an empty place and put new key 225** put new key in its main position; otherwise (colliding node is in its main
231** in its main position; otherwise (colliding node is in its main position), 226** position), new key goes to an empty position.
232** new key goes to an empty position.
233*/ 227*/
234TObject *luaH_set (lua_State *L, Hash *t, const TObject *key) { 228static TObject *newkey (lua_State *L, Hash *t, Node *mp, const TObject *key) {
235 Node *mp = luaH_mainposition(t, key);
236 Node *n = mp;
237 if (!mp)
238 lua_error(L, "table index is nil");
239 do { /* check whether `key' is somewhere in the chain */
240 if (luaO_equalObj(key, &n->key))
241 return &n->val; /* that's all */
242 else n = n->next;
243 } while (n);
244 /* `key' not found; must insert it */
245 if (ttype(&mp->key) != LUA_TNIL) { /* main position is not free? */ 229 if (ttype(&mp->key) != LUA_TNIL) { /* main position is not free? */
246 Node *othern; /* main position of colliding node */ 230 Node *othern = luaH_mainposition(t, &mp->key); /* `mp' of colliding node */
247 n = t->firstfree; /* get a free place */ 231 Node *n = t->firstfree; /* get a free place */
248 /* is colliding node out of its main position? (can only happens if 232 if (othern != mp) { /* is colliding node out of its main position? */
249 its position is after "firstfree") */
250 if (mp > n && (othern=luaH_mainposition(t, &mp->key)) != mp) {
251 /* yes; move colliding node into free position */ 233 /* yes; move colliding node into free position */
252 while (othern->next != mp) othern = othern->next; /* find previous */ 234 while (othern->next != mp) othern = othern->next; /* find previous */
253 othern->next = n; /* redo the chain with `n' in place of `mp' */ 235 othern->next = n; /* redo the chain with `n' in place of `mp' */
@@ -273,25 +255,57 @@ TObject *luaH_set (lua_State *L, Hash *t, const TObject *key) {
273} 255}
274 256
275 257
276TObject *luaH_setint (lua_State *L, Hash *t, int key) { 258static TObject *luaH_setany (lua_State *L, Hash *t, const TObject *key) {
277 TObject index; 259 Node *mp = luaH_mainposition(t, key);
278 ttype(&index) = LUA_TNUMBER; 260 Node *n = mp;
279 nvalue(&index) = key; 261 if (!mp)
280 return luaH_set(L, t, &index); 262 lua_error(L, "table index is nil");
263 do { /* check whether `key' is somewhere in the chain */
264 if (luaO_equalObj(key, &n->key))
265 return &n->val; /* that's all */
266 else n = n->next;
267 } while (n);
268 return newkey(L, t, mp, key); /* `key' not found; must insert it */
269}
270
271
272TObject *luaH_setnum (lua_State *L, Hash *t, lua_Number key) {
273 TObject kobj;
274 Node *mp = hashnum(t, key);
275 Node *n = mp;
276 do { /* check whether `key' is somewhere in the chain */
277 if (nvalue(&n->key) == key && ttype(&n->key) == LUA_TNUMBER)
278 return &n->val; /* that's all */
279 else n = n->next;
280 } while (n);
281 /* `key' not found; must insert it */
282 ttype(&kobj) = LUA_TNUMBER;
283 nvalue(&kobj) = key;
284 return newkey(L, t, mp, &kobj);
281} 285}
282 286
283 287
284void luaH_setstrnum (lua_State *L, Hash *t, TString *key, lua_Number val) { 288TObject *luaH_setstr (lua_State *L, Hash *t, TString *key) {
285 TObject *value, index; 289 TObject kobj;
286 ttype(&index) = LUA_TSTRING; 290 Node *mp = hashstr(t, key);
287 tsvalue(&index) = key; 291 Node *n = mp;
288 value = luaH_set(L, t, &index); 292 do { /* check whether `key' is somewhere in the chain */
289 ttype(value) = LUA_TNUMBER; 293 if (tsvalue(&n->key) == key && ttype(&n->key) == LUA_TSTRING)
290 nvalue(value) = val; 294 return &n->val; /* that's all */
295 else n = n->next;
296 } while (n);
297 /* `key' not found; must insert it */
298 ttype(&kobj) = LUA_TSTRING;
299 tsvalue(&kobj) = key;
300 return newkey(L, t, mp, &kobj);
291} 301}
292 302
293 303
294const TObject *luaH_getglobal (lua_State *L, const char *name) { 304TObject *luaH_set (lua_State *L, Hash *t, const TObject *key) {
295 return luaH_getstr(L->gt, luaS_new(L, name)); 305 switch (ttype(key)) {
306 case LUA_TNUMBER: return luaH_setnum(L, t, nvalue(key));
307 case LUA_TSTRING: return luaH_setstr(L, t, tsvalue(key));
308 default: return luaH_setany(L, t, key);
309 }
296} 310}
297 311