diff options
Diffstat (limited to 'lua/lstring.c')
-rw-r--r-- | lua/lstring.c | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/lua/lstring.c b/lua/lstring.c new file mode 100644 index 000000000..8f194ec8a --- /dev/null +++ b/lua/lstring.c @@ -0,0 +1,102 @@ +/* +** $Id: lstring.c,v 1.1 2004/03/16 21:58:30 niemeyer Exp $ +** String table (keeps all strings handled by Lua) +** See Copyright Notice in lua.h +*/ + + +#include <string.h> + +#define lstring_c + +#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) { + GCObject **newhash = luaM_newvector(L, newsize, GCObject *); + stringtable *tb = &G(L)->strt; + int i; + for (i=0; i<newsize; i++) newhash[i] = NULL; + /* rehash */ + for (i=0; i<tb->size; i++) { + GCObject *p = tb->hash[i]; + while (p) { /* for each node in the list */ + GCObject *next = p->gch.next; /* save next */ + lu_hash h = gcotots(p)->tsv.hash; + int h1 = lmod(h, newsize); /* new position */ + lua_assert(cast(int, h%newsize) == lmod(h, newsize)); + p->gch.next = newhash[h1]; /* chain it */ + 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 char *str, size_t l, lu_hash h) { + TString *ts = cast(TString *, luaM_malloc(L, sizestring(l))); + stringtable *tb; + ts->tsv.len = l; + ts->tsv.hash = h; + ts->tsv.marked = 0; + ts->tsv.tt = LUA_TSTRING; + ts->tsv.reserved = 0; + memcpy(ts+1, str, l*sizeof(char)); + ((char *)(ts+1))[l] = '\0'; /* ending 0 */ + tb = &G(L)->strt; + h = lmod(h, tb->size); + ts->tsv.next = tb->hash[h]; /* chain new entry */ + tb->hash[h] = valtogco(ts); + tb->nuse++; + if (tb->nuse > cast(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 char *str, size_t l) { + GCObject *o; + lu_hash h = (lu_hash)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)+(unsigned char)(str[l1-1])); + for (o = G(L)->strt.hash[lmod(h, G(L)->strt.size)]; + o != NULL; + o = o->gch.next) { + TString *ts = gcotots(o); + 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; + u = cast(Udata *, luaM_malloc(L, sizeudata(s))); + u->uv.marked = (1<<1); /* is not finalized */ + u->uv.tt = LUA_TUSERDATA; + u->uv.len = s; + u->uv.metatable = hvalue(defaultmeta(L)); + /* chain it on udata list */ + u->uv.next = G(L)->rootudata; + G(L)->rootudata = valtogco(u); + return u; +} + |