Mercurial > vba-clojure
view src/lua/lstring.c @ 311:8fa0f36140b4
began writing out my notes on the ROM in an org file.
author | Dylan Holmes <ocsenave@gmail.com> |
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date | Sun, 01 Apr 2012 03:20:33 -0500 |
parents | 27763b933818 |
children |
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1 /*2 ** $Id: lstring.c,v 2.8.1.1 2007/12/27 13:02:25 roberto Exp $3 ** String table (keeps all strings handled by Lua)4 ** See Copyright Notice in lua.h5 */8 #include <string.h>10 #define lstring_c11 #define LUA_CORE13 #include "lua.h"15 #include "lmem.h"16 #include "lobject.h"17 #include "lstate.h"18 #include "lstring.h"22 void luaS_resize (lua_State *L, int newsize) {23 GCObject **newhash;24 stringtable *tb;25 int i;26 if (G(L)->gcstate == GCSsweepstring)27 return; /* cannot resize during GC traverse */28 newhash = luaM_newvector(L, newsize, GCObject *);29 tb = &G(L)->strt;30 for (i=0; i<newsize; i++) newhash[i] = NULL;31 /* rehash */32 for (i=0; i<tb->size; i++) {33 GCObject *p = tb->hash[i];34 while (p) { /* for each node in the list */35 GCObject *next = p->gch.next; /* save next */36 unsigned int h = gco2ts(p)->hash;37 int h1 = lmod(h, newsize); /* new position */38 lua_assert(cast_int(h%newsize) == lmod(h, newsize));39 p->gch.next = newhash[h1]; /* chain it */40 newhash[h1] = p;41 p = next;42 }43 }44 luaM_freearray(L, tb->hash, tb->size, TString *);45 tb->size = newsize;46 tb->hash = newhash;47 }50 static TString *newlstr (lua_State *L, const char *str, size_t l,51 unsigned int h) {52 TString *ts;53 stringtable *tb;54 if (l+1 > (MAX_SIZET - sizeof(TString))/sizeof(char))55 luaM_toobig(L);56 ts = cast(TString *, luaM_malloc(L, (l+1)*sizeof(char)+sizeof(TString)));57 ts->tsv.len = l;58 ts->tsv.hash = h;59 ts->tsv.marked = luaC_white(G(L));60 ts->tsv.tt = LUA_TSTRING;61 ts->tsv.reserved = 0;62 memcpy(ts+1, str, l*sizeof(char));63 ((char *)(ts+1))[l] = '\0'; /* ending 0 */64 tb = &G(L)->strt;65 h = lmod(h, tb->size);66 ts->tsv.next = tb->hash[h]; /* chain new entry */67 tb->hash[h] = obj2gco(ts);68 tb->nuse++;69 if (tb->nuse > cast(lu_int32, tb->size) && tb->size <= MAX_INT/2)70 luaS_resize(L, tb->size*2); /* too crowded */71 return ts;72 }75 TString *luaS_newlstr (lua_State *L, const char *str, size_t l) {76 GCObject *o;77 unsigned int h = cast(unsigned int, l); /* seed */78 size_t step = (l>>5)+1; /* if string is too long, don't hash all its chars */79 size_t l1;80 for (l1=l; l1>=step; l1-=step) /* compute hash */81 h = h ^ ((h<<5)+(h>>2)+cast(unsigned char, str[l1-1]));82 for (o = G(L)->strt.hash[lmod(h, G(L)->strt.size)];83 o != NULL;84 o = o->gch.next) {85 TString *ts = rawgco2ts(o);86 if (ts->tsv.len == l && (memcmp(str, getstr(ts), l) == 0)) {87 /* string may be dead */88 if (isdead(G(L), o)) changewhite(o);89 return ts;90 }91 }92 return newlstr(L, str, l, h); /* not found */93 }96 Udata *luaS_newudata (lua_State *L, size_t s, Table *e) {97 Udata *u;98 if (s > MAX_SIZET - sizeof(Udata))99 luaM_toobig(L);100 u = cast(Udata *, luaM_malloc(L, s + sizeof(Udata)));101 u->uv.marked = luaC_white(G(L)); /* is not finalized */102 u->uv.tt = LUA_TUSERDATA;103 u->uv.len = s;104 u->uv.metatable = NULL;105 u->uv.env = e;106 /* chain it on udata list (after main thread) */107 u->uv.next = G(L)->mainthread->next;108 G(L)->mainthread->next = obj2gco(u);109 return u;110 }