rusefi
/
lua
mirror of https://github.com/rusefi/lua.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

'index2value' more robust 

'index2value' accepts pseudo-indices also when called from a Lua
function, through a hook.
This commit is contained in:
Roberto Ierusalimschy 2021-05-24 16:48:43 -03:00
parent 1e6918d553
commit fc6c74f100
1 changed files with 13 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
lapi.c
View File

@ -53,6 +53,10 @@ const char lua_ident[] =
#define isupvalue(i) ((i) < LUA_REGISTRYINDEX) #define isupvalue(i) ((i) < LUA_REGISTRYINDEX)
/*
** Convert an acceptable index to a pointer to its respective value.
** Non-valid indices return the special nil value 'G(L)->nilvalue'.
*/
static TValue *index2value (lua_State *L, int idx) { static TValue *index2value (lua_State *L, int idx) {
CallInfo *ci = L->ci; CallInfo *ci = L->ci;
if (idx > 0) { if (idx > 0) {
@ -70,22 +74,26 @@ static TValue *index2value (lua_State *L, int idx) {
else { /* upvalues */ else { /* upvalues */
idx = LUA_REGISTRYINDEX - idx; idx = LUA_REGISTRYINDEX - idx;
api_check(L, idx <= MAXUPVAL + 1, "upvalue index too large"); api_check(L, idx <= MAXUPVAL + 1, "upvalue index too large");
if (ttislcf(s2v(ci->func))) /* light C function? */ if (ttisCclosure(s2v(ci->func))) { /* C closure? */
return &G(L)->nilvalue; /* it has no upvalues */
else {
CClosure *func = clCvalue(s2v(ci->func)); CClosure *func = clCvalue(s2v(ci->func));
return (idx <= func->nupvalues) ? &func->upvalue[idx-1] return (idx <= func->nupvalues) ? &func->upvalue[idx-1]
: &G(L)->nilvalue; : &G(L)->nilvalue;
} }
else { /* light C function or Lua function (through a hook)?) */
api_check(L, ttislcf(s2v(ci->func)), "caller not a C function");
return &G(L)->nilvalue; /* no upvalues */
}
} }
} }
/*
** Convert a valid actual index (not a pseudo-index) to its address.
*/
static StkId index2stack (lua_State *L, int idx) { static StkId index2stack (lua_State *L, int idx) {
CallInfo *ci = L->ci; CallInfo *ci = L->ci;
if (idx > 0) { if (idx > 0) {
StkId o = ci->func + idx; StkId o = ci->func + idx;
api_check(L, o < L->top, "unacceptable index"); api_check(L, o < L->top, "invalid index");
return o; return o;
} }
else { /* non-positive index */ else { /* non-positive index */