| /* |
| ** $Id: lstring.c,v 1.64 2001/06/07 15:01:21 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->tsv.nexthash; /* save next */ |
| lu_hash h = p->tsv.hash; |
| int h1 = lmod(h, newsize); /* new position */ |
| lua_assert((int)(h%newsize) == lmod(h, newsize)); |
| p->tsv.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->tsv.nexthash = NULL; |
| ts->tsv.len = l; |
| ts->tsv.hash = h; |
| ts->tsv.marked = 0; |
| ts->tsv.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->tsv.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 != NULL; |
| ts = ts->tsv.nexthash) { |
| if (ts->tsv.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->uv.len = s; |
| u->uv.tag = 0; |
| u->uv.value = u + 1; |
| /* chain it on udata list */ |
| u->uv.next = G(L)->rootudata; |
| G(L)->rootudata = u; |
| return u; |
| } |
| |