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-rw-r--r--src/lstring.c111
1 files changed, 111 insertions, 0 deletions
diff --git a/src/lstring.c b/src/lstring.c
new file mode 100644
index 0000000..4911315
--- /dev/null
+++ b/src/lstring.c
@@ -0,0 +1,111 @@
+/*
+** $Id: lstring.c,v 2.8.1.1 2007/12/27 13:02:25 roberto Exp $
+** String table (keeps all strings handled by Lua)
+** See Copyright Notice in lua.h
+*/
+
+
+#include <string.h>
+
+#define lstring_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+#include "lstring.h"
+
+
+
+void luaS_resize (lua_State *L, int newsize) {
+ GCObject **newhash;
+ stringtable *tb;
+ int i;
+ if (G(L)->gcstate == GCSsweepstring)
+ return; /* cannot resize during GC traverse */
+ newhash = luaM_newvector(L, newsize, GCObject *);
+ tb = &G(L)->strt;
+ 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 */
+ unsigned int h = gco2ts(p)->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,
+ unsigned int h) {
+ TString *ts;
+ stringtable *tb;
+ if (l+1 > (MAX_SIZET - sizeof(TString))/sizeof(char))
+ luaM_toobig(L);
+ ts = cast(TString *, luaM_malloc(L, (l+1)*sizeof(char)+sizeof(TString)));
+ ts->tsv.len = l;
+ ts->tsv.hash = h;
+ ts->tsv.marked = luaC_white(G(L));
+ 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] = obj2gco(ts);
+ tb->nuse++;
+ if (tb->nuse > cast(lu_int32, 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;
+ unsigned int h = cast(unsigned int, 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)+cast(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 = rawgco2ts(o);
+ if (ts->tsv.len == l && (memcmp(str, getstr(ts), l) == 0)) {
+ /* string may be dead */
+ if (isdead(G(L), o)) changewhite(o);
+ return ts;
+ }
+ }
+ return newlstr(L, str, l, h); /* not found */
+}
+
+
+Udata *luaS_newudata (lua_State *L, size_t s, Table *e) {
+ Udata *u;
+ if (s > MAX_SIZET - sizeof(Udata))
+ luaM_toobig(L);
+ u = cast(Udata *, luaM_malloc(L, s + sizeof(Udata)));
+ u->uv.marked = luaC_white(G(L)); /* is not finalized */
+ u->uv.tt = LUA_TUSERDATA;
+ u->uv.len = s;
+ u->uv.metatable = NULL;
+ u->uv.env = e;
+ /* chain it on udata list (after main thread) */
+ u->uv.next = G(L)->mainthread->next;
+ G(L)->mainthread->next = obj2gco(u);
+ return u;
+}
+