l_noret luaD_throw (lua_State *L, int errcode) {
if (L->errorJmp) { /* thread has an error handler? */
L->errorJmp->status = errcode; /* set status */
LUAI_THROW(L, L->errorJmp); /* jump to it */
}
else { /* thread has no error handler */
L->status = cast_byte(errcode); /* mark it as dead */
if (G(L)->mainthread->errorJmp) { /* main thread has a handler? */
setobjs2s(L, G(L)->mainthread->top++, L->top - 1); /* copy error obj. */
luaD_throw(G(L)->mainthread, errcode); /* re-throw in main thread */
}
else { /* no handler at all; abort */
if (G(L)->panic) { /* panic function? */
lua_unlock(L);
G(L)->panic(L); /* call it (last chance to jump out) */
}
abort();
}
}
}
/*
** generic allocation routine.
*/
void *luaM_realloc_ (lua_State *L, void *block, size_t osize, size_t nsize) {
void *newblock;
global_State *g = G(L);
size_t realosize = (block) ? osize : 0;
lua_assert((realosize == 0) == (block == NULL));
#if defined(HARDMEMTESTS)
if (nsize > realosize && g->gcrunning)
luaC_fullgc(L, 1); /* force a GC whenever possible */
#endif
newblock = (*g->frealloc)(g->ud, block, osize, nsize);
if (newblock == NULL && nsize > 0) {
api_check(L, nsize > realosize,
"realloc cannot fail when shrinking a block");
if (g->gcrunning) {
luaC_fullgc(L, 1); /* try to free some memory... */
newblock = (*g->frealloc)(g->ud, block, osize, nsize); /* try again */
}
if (newblock == NULL)
luaD_throw(L, LUA_ERRMEM);
}
lua_assert((nsize == 0) == (newblock == NULL));
g->GCdebt = (g->GCdebt + nsize) - realosize;
#if defined(TRACEMEM)
{ /* auxiliary patch to monitor garbage collection.
** To plot, gnuplot with following command:
** plot TRACEMEM using 1:2 with lines, TRACEMEM using 1:3 with lines
*/
static unsigned long total = 0; /* our "time" */
static FILE *f = NULL; /* output file */
total++; /* "time" always grows */
if ((total % 200) == 0) {
if (f == NULL) f = fopen(TRACEMEM, "w");
fprintf(f, "%lu %u %d %d\n", total,
gettotalbytes(g), g->GCdebt, g->gcstate * 10000);
}
}
#endif
return newblock;
}
/**
* 调用此函数前，参数都经过检查, 保证了分配的内存块不会过大;
*
* 创建对象的函数 luaM_newobject 也调用此函数(lmem.h):
* #define luaM_newobject(L,tag,s) luaM_realloc_(L, NULL, tag, (s))
*
* nsize 为 0 表示释放内存
* #define luaM_freearray(L, b, n) luaM_realloc_(L, (b), (n)*sizeof(*(b)), 0)
*
* 内部调用 g->frealloc 来重新分配内存
*/
void *luaM_realloc_ (lua_State *L, void *block, size_t osize, size_t nsize) {
void *newblock;
global_State *g = G(L);
size_t realosize = (block) ? osize : 0;
lua_assert((realosize == 0) == (block == NULL));
#if defined(HARDMEMTESTS)
if (nsize > realosize && g->gcrunning)
luaC_fullgc(L, 1); /* force a GC whenever possible */
#endif
newblock = (*g->frealloc)(g->ud, block, osize, nsize);
if (newblock == NULL && nsize > 0) {
api_check( nsize > realosize,
"realloc cannot fail when shrinking a block");
luaC_fullgc(L, 1); /* try to free some memory... */
newblock = (*g->frealloc)(g->ud, block, osize, nsize); /* try again */
if (newblock == NULL)
luaD_throw(L, LUA_ERRMEM);
}
lua_assert((nsize == 0) == (newblock == NULL));
g->GCdebt = (g->GCdebt + nsize) - realosize;
return newblock;
}
static void traceexec (lua_State *L) {
CallInfo *ci = L->ci;
lu_byte mask = L->hookmask;
if ((mask & LUA_MASKCOUNT) && L->hookcount == 0) {
resethookcount(L);
luaD_hook(L, LUA_HOOKCOUNT, -1);
}
if (mask & LUA_MASKLINE) {
Proto *p = ci_func(ci)->p;
int npc = pcRel(ci->u.l.savedpc, p);
int newline = getfuncline(p, npc);
if (npc == 0 || /* call linehook when enter a new function, */
ci->u.l.savedpc <= L->oldpc || /* when jump back (loop), or when */
newline != getfuncline(p, pcRel(L->oldpc, p))) /* enter a new line */
luaD_hook(L, LUA_HOOKLINE, newline);
}
L->oldpc = ci->u.l.savedpc;
if (L->status == LUA_YIELD) { /* did hook yield? */
ci->u.l.savedpc--; /* undo increment (resume will increment it again) */
luaD_throw(L, LUA_YIELD);
}
}
l_noret luaD_throw (lua_State *L, int errcode) {
if (L->errorJmp) { /* thread has an error handler? */
L->errorJmp->status = errcode; /* set status */
LUAI_THROW(L, L->errorJmp); /* jump to it */
}
else { /* thread has no error handler */
global_State *g = G(L);
L->status = cast_byte(errcode); /* mark it as dead */
if (g->mainthread->errorJmp) { /* main thread has a handler? */
setobjs2s(L, g->mainthread->top++, L->top - 1); /* copy error obj. */
luaD_throw(g->mainthread, errcode); /* re-throw in main thread */
}
else { /* no handler at all; abort */
if (g->panic) { /* panic function? */
seterrorobj(L, errcode, L->top); /* assume EXTRA_STACK */
if (L->ci->top < L->top)
L->ci->top = L->top; /* pushing msg. can break this invariant */
lua_unlock(L);
g->panic(L); /* call panic function (last chance to jump out) */
}
abort();
}
}
}
static l_noret lexerror (LexState *ls, const char *msg, int token) {
msg = luaG_addinfo(ls->L, msg, ls->source, ls->linenumber);
if (token)
luaO_pushfstring(ls->L, "%s near %s", msg, txtToken(ls, token));
luaD_throw(ls->L, LUA_ERRSYNTAX);
}
static void error(LoadState* S, const char* why)
{
luaO_pushfstring(S->L,"%s: %s in precompiled chunk",S->name,why);
luaD_throw(S->L,LUA_ERRSYNTAX);
}
/*
** open parts that may cause memory-allocation errors
*/
static void f_luaopen (lua_State *L, void *ud) {
int i;
global_State globalState;
lua_State luaState;
global_State *g;
#ifdef _DEBUG
luaState.allocName = "Lua_global_State";
#endif _DEBUG
luaState.l_G = &globalState;
globalState.reallocFunc = luaHelper_Realloc;
globalState.freeFunc = luaHelper_Free;
globalState.memData = luaHelper_memData;
globalState.nblocks = sizeof(lua_State) + sizeof(global_State); // Bogus.
/* create a new global state */
g = luaM_new(&luaState, global_State);
UNUSED(ud);
if (g == NULL) luaD_throw(L, LUA_ERRMEM);
L->l_G = g;
g->mainthread = L;
g->GCthreshold = 0; /* mark it as unfinished state */
g->strt.size = 0;
g->strt.nuse = 0;
g->strt.hash = NULL;
setnilvalue2n(defaultmeta(L));
setnilvalue2n(registry(L));
luaZ_initbuffer(L, &g->buff);
g->panic = default_panic;
#if !LUA_REFCOUNT
g->rootgc = NULL;
g->rootudata = NULL;
g->tmudata = NULL;
#else LUA_REFCOUNT
g->rootgc_head.next = (GCObject*)&g->rootgc_tail;
g->rootgc_head.prev = NULL;
g->rootgc_tail.next = NULL;
g->rootgc_tail.prev = (GCObject*)&g->rootgc_head;
g->rootgc_head.tt = LUA_TNIL;
g->rootgc_head.marked = 0;
g->rootgc_head.ref = 0;
g->rootgc_tail.tt = LUA_TNIL;
g->rootgc_tail.marked = 0;
g->rootgc_tail.ref = 0;
g->rootudata_head.next = (GCObject*)&g->rootudata_tail;
g->rootudata_head.prev = NULL;
g->rootudata_tail.next = NULL;
g->rootudata_tail.prev = (GCObject*)&g->rootudata_head;
g->rootudata_head.tt = LUA_TNIL;
g->rootudata_head.marked = 0;
g->rootudata_head.ref = 0;
g->rootudata_tail.tt = LUA_TNIL;
g->rootudata_tail.marked = 0;
g->rootudata_tail.ref = 0;
g->tmudata_head.next = (GCObject*)&g->tmudata_tail;
g->tmudata_head.prev = NULL;
g->tmudata_tail.next = NULL;
g->tmudata_tail.prev = (GCObject*)&g->tmudata_head;
g->tmudata_head.tt = LUA_TNIL;
g->tmudata_head.marked = 0;
g->tmudata_head.ref = 0;
g->tmudata_tail.tt = LUA_TNIL;
g->tmudata_tail.marked = 0;
g->tmudata_tail.ref = 0;
#endif LUA_REFCOUNT
setnilvalue2n(gkey(g->dummynode));
setnilvalue2n(gval(g->dummynode));
g->dummynode->next = NULL;
g->nblocks = sizeof(lua_State) + sizeof(global_State);
g->reallocFunc = luaHelper_Realloc;
g->freeFunc = luaHelper_Free;
g->memData = luaHelper_memData;
g->fatalErrorFunc = defaultFatalErrorFunc;
#ifdef LUA_MTSUPPORT
g->lockData = NULL;
g->lockFunc = NULL;
g->unlockFunc = NULL;
#endif LUA_MTSUPPORT
g->userGCFunction = NULL;
g->globalUserData = NULL;
stack_init(L, L); /* init stack */
for (i = 0; i < LUA_NTYPES; i++)
{
defaultmetatypes(L, i)->value.gc = NULL;
}
/* create default meta table with a dummy table, and then close the loop */
defaultmeta(L)->tt = LUA_TNUMBER;
defaultmeta(L)->value.gc = NULL;
sethvalue2n(defaultmeta(L), luaH_new(L, 0, 0));
__AddRefDirect(hvalue(defaultmeta(L)));
hvalue(defaultmeta(L))->metatable = hvalue(defaultmeta(L));
__AddRefDirect(hvalue(defaultmeta(L))->metatable);
/* build meta tables */
for (i = 0; i < LUA_NTYPES; i++)
{
luaM_setname(L, "Lua_defaultMetaTypes");
sethvalue2n(defaultmetatypes(L, i), luaH_new(L, 0, 0));
hvalue(defaultmetatypes(L, i))->metatable = hvalue(defaultmeta(L));
}
luaM_setname(L, "Lua_Globals");
sethvalue(gt(L), luaH_new(L, 0, 4)); /* table of globals */
__AddRefDirect(hvalue(gt(L)));
luaM_setname(L, "Lua_Registry");
sethvalue(registry(L), luaH_new(L, 4, 4)); /* registry */
__AddRef(registry(L));
g->minimumstrings = lua_minimumnumstrings;
luaS_resize(L, MINSTRTABSIZE); /* initial size of string table */
luaT_init(L);
luaX_init(L);
luaS_fix(luaS_newliteral(L, MEMERRMSG));
g->GCthreshold = 4*G(L)->nblocks;
luaZ_openspace(L, &g->buff, lua_minimumauxspace);
}
static l_noret error(DumpState* D, const char* why)
{
luaO_pushfstring(D->L,"unable to write precompiled chunk: %s",why);
luaD_throw(D->L,LUA_ERRSYNTAX);
}