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author | Roberto Ierusalimschy <roberto@inf.puc-rio.br> | 2021-05-24 16:48:43 -0300 |
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committer | Roberto Ierusalimschy <roberto@inf.puc-rio.br> | 2021-05-24 16:48:43 -0300 |
commit | fc6c74f1004b5f67d0503633ddb74174a3c8d6ad (patch) | |
tree | ea69269504ddf8272257a3544231317b9362e416 | |
parent | 1e6918d553e0d76148f7de0af63fdce326e049b8 (diff) | |
download | lua-github-fc6c74f1004b5f67d0503633ddb74174a3c8d6ad.tar.gz |
'index2value' more robust
'index2value' accepts pseudo-indices also when called from a Lua
function, through a hook.
-rw-r--r-- | lapi.c | 18 |
1 files changed, 13 insertions, 5 deletions
@@ -53,6 +53,10 @@ const char lua_ident[] = #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) { CallInfo *ci = L->ci; if (idx > 0) { @@ -70,22 +74,26 @@ static TValue *index2value (lua_State *L, int idx) { else { /* upvalues */ idx = LUA_REGISTRYINDEX - idx; api_check(L, idx <= MAXUPVAL + 1, "upvalue index too large"); - if (ttislcf(s2v(ci->func))) /* light C function? */ - return &G(L)->nilvalue; /* it has no upvalues */ - else { + if (ttisCclosure(s2v(ci->func))) { /* C closure? */ CClosure *func = clCvalue(s2v(ci->func)); return (idx <= func->nupvalues) ? &func->upvalue[idx-1] : &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) { CallInfo *ci = L->ci; if (idx > 0) { StkId o = ci->func + idx; - api_check(L, o < L->top, "unacceptable index"); + api_check(L, o < L->top, "invalid index"); return o; } else { /* non-positive index */ |