diff options
Diffstat (limited to '3rdparty/lua/src/lstring.c')
-rw-r--r-- | 3rdparty/lua/src/lstring.c | 135 |
1 files changed, 80 insertions, 55 deletions
diff --git a/3rdparty/lua/src/lstring.c b/3rdparty/lua/src/lstring.c index 9351766fd63..13dcaf4259b 100644 --- a/3rdparty/lua/src/lstring.c +++ b/3rdparty/lua/src/lstring.c @@ -1,5 +1,5 @@ /* -** $Id: lstring.c,v 2.56 2015/11/23 11:32:51 roberto Exp $ +** $Id: lstring.c $ ** String table (keeps all strings handled by Lua) ** See Copyright Notice in lua.h */ @@ -22,16 +22,10 @@ #include "lstring.h" -#define MEMERRMSG "not enough memory" - - /* -** Lua will use at most ~(2^LUAI_HASHLIMIT) bytes from a string to -** compute its hash +** Maximum size for string table. */ -#if !defined(LUAI_HASHLIMIT) -#define LUAI_HASHLIMIT 5 -#endif +#define MAXSTRTB cast_int(luaM_limitN(MAX_INT, TString*)) /* @@ -39,7 +33,7 @@ */ int luaS_eqlngstr (TString *a, TString *b) { size_t len = a->u.lnglen; - lua_assert(a->tt == LUA_TLNGSTR && b->tt == LUA_TLNGSTR); + lua_assert(a->tt == LUA_VLNGSTR && b->tt == LUA_VLNGSTR); return (a == b) || /* same instance or... */ ((len == b->u.lnglen) && /* equal length and ... */ (memcmp(getstr(a), getstr(b), len) == 0)); /* equal contents */ @@ -47,52 +41,65 @@ int luaS_eqlngstr (TString *a, TString *b) { unsigned int luaS_hash (const char *str, size_t l, unsigned int seed) { - unsigned int h = seed ^ cast(unsigned int, l); - size_t step = (l >> LUAI_HASHLIMIT) + 1; - for (; l >= step; l -= step) + unsigned int h = seed ^ cast_uint(l); + for (; l > 0; l--) h ^= ((h<<5) + (h>>2) + cast_byte(str[l - 1])); return h; } unsigned int luaS_hashlongstr (TString *ts) { - lua_assert(ts->tt == LUA_TLNGSTR); + lua_assert(ts->tt == LUA_VLNGSTR); if (ts->extra == 0) { /* no hash? */ - ts->hash = luaS_hash(getstr(ts), ts->u.lnglen, ts->hash); + size_t len = ts->u.lnglen; + ts->hash = luaS_hash(getstr(ts), len, ts->hash); ts->extra = 1; /* now it has its hash */ } return ts->hash; } -/* -** resizes the string table -*/ -void luaS_resize (lua_State *L, int newsize) { +static void tablerehash (TString **vect, int osize, int nsize) { int i; - stringtable *tb = &G(L)->strt; - if (newsize > tb->size) { /* grow table if needed */ - luaM_reallocvector(L, tb->hash, tb->size, newsize, TString *); - for (i = tb->size; i < newsize; i++) - tb->hash[i] = NULL; - } - for (i = 0; i < tb->size; i++) { /* rehash */ - TString *p = tb->hash[i]; - tb->hash[i] = NULL; - while (p) { /* for each node in the list */ + for (i = osize; i < nsize; i++) /* clear new elements */ + vect[i] = NULL; + for (i = 0; i < osize; i++) { /* rehash old part of the array */ + TString *p = vect[i]; + vect[i] = NULL; + while (p) { /* for each string in the list */ TString *hnext = p->u.hnext; /* save next */ - unsigned int h = lmod(p->hash, newsize); /* new position */ - p->u.hnext = tb->hash[h]; /* chain it */ - tb->hash[h] = p; + unsigned int h = lmod(p->hash, nsize); /* new position */ + p->u.hnext = vect[h]; /* chain it into array */ + vect[h] = p; p = hnext; } } - if (newsize < tb->size) { /* shrink table if needed */ - /* vanishing slice should be empty */ - lua_assert(tb->hash[newsize] == NULL && tb->hash[tb->size - 1] == NULL); - luaM_reallocvector(L, tb->hash, tb->size, newsize, TString *); +} + + +/* +** Resize the string table. If allocation fails, keep the current size. +** (This can degrade performance, but any non-zero size should work +** correctly.) +*/ +void luaS_resize (lua_State *L, int nsize) { + stringtable *tb = &G(L)->strt; + int osize = tb->size; + TString **newvect; + if (nsize < osize) /* shrinking table? */ + tablerehash(tb->hash, osize, nsize); /* depopulate shrinking part */ + newvect = luaM_reallocvector(L, tb->hash, osize, nsize, TString*); + if (l_unlikely(newvect == NULL)) { /* reallocation failed? */ + if (nsize < osize) /* was it shrinking table? */ + tablerehash(tb->hash, nsize, osize); /* restore to original size */ + /* leave table as it was */ + } + else { /* allocation succeeded */ + tb->hash = newvect; + tb->size = nsize; + if (nsize > osize) + tablerehash(newvect, osize, nsize); /* rehash for new size */ } - tb->size = newsize; } @@ -104,8 +111,8 @@ void luaS_clearcache (global_State *g) { int i, j; for (i = 0; i < STRCACHE_N; i++) for (j = 0; j < STRCACHE_M; j++) { - if (iswhite(g->strcache[i][j])) /* will entry be collected? */ - g->strcache[i][j] = g->memerrmsg; /* replace it with something fixed */ + if (iswhite(g->strcache[i][j])) /* will entry be collected? */ + g->strcache[i][j] = g->memerrmsg; /* replace it with something fixed */ } } @@ -116,7 +123,10 @@ void luaS_clearcache (global_State *g) { void luaS_init (lua_State *L) { global_State *g = G(L); int i, j; - luaS_resize(L, MINSTRTABSIZE); /* initial size of string table */ + stringtable *tb = &G(L)->strt; + tb->hash = luaM_newvector(L, MINSTRTABSIZE, TString*); + tablerehash(tb->hash, 0, MINSTRTABSIZE); /* clear array */ + tb->size = MINSTRTABSIZE; /* pre-create memory-error message */ g->memerrmsg = luaS_newliteral(L, MEMERRMSG); luaC_fix(L, obj2gco(g->memerrmsg)); /* it should never be collected */ @@ -145,7 +155,7 @@ static TString *createstrobj (lua_State *L, size_t l, int tag, unsigned int h) { TString *luaS_createlngstrobj (lua_State *L, size_t l) { - TString *ts = createstrobj(L, l, LUA_TLNGSTR, G(L)->seed); + TString *ts = createstrobj(L, l, LUA_VLNGSTR, G(L)->seed); ts->u.lnglen = l; return ts; } @@ -161,34 +171,46 @@ void luaS_remove (lua_State *L, TString *ts) { } +static void growstrtab (lua_State *L, stringtable *tb) { + if (l_unlikely(tb->nuse == MAX_INT)) { /* too many strings? */ + luaC_fullgc(L, 1); /* try to free some... */ + if (tb->nuse == MAX_INT) /* still too many? */ + luaM_error(L); /* cannot even create a message... */ + } + if (tb->size <= MAXSTRTB / 2) /* can grow string table? */ + luaS_resize(L, tb->size * 2); +} + + /* -** checks whether short string exists and reuses it or creates a new one +** Checks whether short string exists and reuses it or creates a new one. */ static TString *internshrstr (lua_State *L, const char *str, size_t l) { TString *ts; global_State *g = G(L); + stringtable *tb = &g->strt; unsigned int h = luaS_hash(str, l, g->seed); - TString **list = &g->strt.hash[lmod(h, g->strt.size)]; + TString **list = &tb->hash[lmod(h, tb->size)]; lua_assert(str != NULL); /* otherwise 'memcmp'/'memcpy' are undefined */ for (ts = *list; ts != NULL; ts = ts->u.hnext) { - if (l == ts->shrlen && - (memcmp(str, getstr(ts), l * sizeof(char)) == 0)) { + if (l == ts->shrlen && (memcmp(str, getstr(ts), l * sizeof(char)) == 0)) { /* found! */ if (isdead(g, ts)) /* dead (but not collected yet)? */ changewhite(ts); /* resurrect it */ return ts; } } - if (g->strt.nuse >= g->strt.size && g->strt.size <= MAX_INT/2) { - luaS_resize(L, g->strt.size * 2); - list = &g->strt.hash[lmod(h, g->strt.size)]; /* recompute with new size */ + /* else must create a new string */ + if (tb->nuse >= tb->size) { /* need to grow string table? */ + growstrtab(L, tb); + list = &tb->hash[lmod(h, tb->size)]; /* rehash with new size */ } - ts = createstrobj(L, l, LUA_TSHRSTR, h); + ts = createstrobj(L, l, LUA_VSHRSTR, h); memcpy(getstr(ts), str, l * sizeof(char)); ts->shrlen = cast_byte(l); ts->u.hnext = *list; *list = ts; - g->strt.nuse++; + tb->nuse++; return ts; } @@ -201,7 +223,7 @@ TString *luaS_newlstr (lua_State *L, const char *str, size_t l) { return internshrstr(L, str, l); else { TString *ts; - if (l >= (MAX_SIZE - sizeof(TString))/sizeof(char)) + if (l_unlikely(l >= (MAX_SIZE - sizeof(TString))/sizeof(char))) luaM_toobig(L); ts = luaS_createlngstrobj(L, l); memcpy(getstr(ts), str, l * sizeof(char)); @@ -233,16 +255,19 @@ TString *luaS_new (lua_State *L, const char *str) { } -Udata *luaS_newudata (lua_State *L, size_t s) { +Udata *luaS_newudata (lua_State *L, size_t s, int nuvalue) { Udata *u; + int i; GCObject *o; - if (s > MAX_SIZE - sizeof(Udata)) + if (l_unlikely(s > MAX_SIZE - udatamemoffset(nuvalue))) luaM_toobig(L); - o = luaC_newobj(L, LUA_TUSERDATA, sizeludata(s)); + o = luaC_newobj(L, LUA_VUSERDATA, sizeudata(nuvalue, s)); u = gco2u(o); u->len = s; + u->nuvalue = nuvalue; u->metatable = NULL; - setuservalue(L, u, luaO_nilobject); + for (i = 0; i < nuvalue; i++) + setnilvalue(&u->uv[i].uv); return u; } |