'luaV_concat' can "concat" one single value

Several of its callers needed that case and had to do the check
themselves.
This commit is contained in:
Roberto Ierusalimschy 2020-07-03 11:54:58 -03:00
parent e96385aded
commit ae809e9fd1
3 changed files with 9 additions and 14 deletions

8
lapi.c
View File

@ -1239,14 +1239,12 @@ LUA_API void lua_toclose (lua_State *L, int idx) {
LUA_API void lua_concat (lua_State *L, int n) {
lua_lock(L);
api_checknelems(L, n);
if (n >= 2) {
if (n > 0)
luaV_concat(L, n);
}
else if (n == 0) { /* push empty string */
setsvalue2s(L, L->top, luaS_newlstr(L, "", 0));
else { /* nothing to concatenate */
setsvalue2s(L, L->top, luaS_newlstr(L, "", 0)); /* push empty string */
api_incr_top(L);
}
/* else n == 1; nothing to do */
luaC_checkGC(L);
lua_unlock(L);
}

View File

@ -402,10 +402,8 @@ static void pushstr (BuffFS *buff, const char *str, size_t l) {
setsvalue2s(L, L->top, luaS_newlstr(L, str, l));
L->top++; /* may use one extra slot */
buff->pushed++;
if (buff->pushed > 1) {
luaV_concat(L, buff->pushed); /* join partial results into one */
buff->pushed = 1;
}
luaV_concat(L, buff->pushed); /* join partial results into one */
buff->pushed = 1;
}

9
lvm.c
View File

@ -634,7 +634,8 @@ static void copy2buff (StkId top, int n, char *buff) {
** from 'L->top - total' up to 'L->top - 1'.
*/
void luaV_concat (lua_State *L, int total) {
lua_assert(total >= 2);
if (total == 1)
return; /* "all" values already concatenated */
do {
StkId top = L->top;
int n = 2; /* number of elements handled in this pass (at least 2) */
@ -840,10 +841,8 @@ void luaV_finishOp (lua_State *L) {
int a = GETARG_A(inst); /* first element to concatenate */
int total = cast_int(top - 1 - (base + a)); /* yet to concatenate */
setobjs2s(L, top - 2, top); /* put TM result in proper position */
if (total > 1) { /* are there elements to concat? */
L->top = top - 1; /* top is one after last element (at top-2) */
luaV_concat(L, total); /* concat them (may yield again) */
}
L->top = top - 1; /* top is one after last element (at top-2) */
luaV_concat(L, total); /* concat them (may yield again) */
break;
}
default: {