static int tinsert (lv_State *L) {
lv_clearFirstTableValue(L);
int e = aux_getn(L, 1) + 1; /* first empty element */
int pos; /* where to insert new element */
switch (lv_gettop(L)) {
case 2: { /* called with only 2 arguments */
pos = e; /* insert new element at the end */
break;
}
case 3: {
int i;
pos = lvL_checkint(L, 2); /* 2nd argument is the position */
if (pos > e) e = pos; /* `grow' array if necessary */
for (i = e; i > pos; i--) { /* move up elements */
lv_rawgeti(L, 1, i-1);
lv_rawseti(L, 1, i); /* t[i] = t[i-1] */
}
break;
}
default: {
return lvL_error(L, "wrong number of arguments to " LV_QL("insert"));
}
}
lvL_setn(L, 1, e); /* new size */
lv_rawseti(L, 1, pos); /* t[pos] = v */
return 0;
}
static void addfield (lv_State *L, lvL_Buffer *b, int i) {
lv_rawgeti(L, 1, i);
if (!lv_isstring(L, -1))
lvL_error(L, "invalid value (%s) at index %d in table for "
LV_QL("concat"), lvL_typename(L, -1), i);
lvL_addvalue(b);
}
static int db_setfenv (lv_State *L) {
lvL_checktype(L, 2, LV_TTABLE);
lv_settop(L, 2);
if (lv_setfenv(L, 1) == 0)
lvL_error(L, LV_QL("setfenv")
" cannot change environment of given object");
return 1;
}
static int setn (lv_State *L) {
lv_clearFirstTableValue(L);
lvL_checktype(L, 1, LV_TTABLE);
#ifndef lvL_setn
lvL_setn(L, 1, lvL_checkint(L, 2));
#else
lvL_error(L, LV_QL("setn") " is obsolete");
#endif
lv_pushvalue(L, 1);
return 1;
}
static int getfield (lv_State *L, const char *key, int d) {
int res;
lv_getfield(L, -1, key);
if (lv_isnumber(L, -1))
res = (int)lv_tointeger(L, -1);
else {
if (d < 0)
return lvL_error(L, "field " LV_QS " missing in date table", key);
res = d;
}
lv_pop(L, 1);
return res;
}
static void auxsort (lv_State *L, int l, int u) {
while (l < u) { /* for tail recursion */
int i, j;
/* sort elements a[l], a[(l+u)/2] and a[u] */
lv_rawgeti(L, 1, l);
lv_rawgeti(L, 1, u);
if (sort_comp(L, -1, -2)) /* a[u] < a[l]? */
set2(L, l, u); /* swap a[l] - a[u] */
else
lv_pop(L, 2);
if (u-l == 1) break; /* only 2 elements */
i = (l+u)/2;
lv_rawgeti(L, 1, i);
lv_rawgeti(L, 1, l);
if (sort_comp(L, -2, -1)) /* a[i]<a[l]? */
set2(L, i, l);
else {
lv_pop(L, 1); /* remove a[l] */
lv_rawgeti(L, 1, u);
if (sort_comp(L, -1, -2)) /* a[u]<a[i]? */
set2(L, i, u);
else
lv_pop(L, 2);
}
if (u-l == 2) break; /* only 3 elements */
lv_rawgeti(L, 1, i); /* Pivot */
lv_pushvalue(L, -1);
lv_rawgeti(L, 1, u-1);
set2(L, i, u-1);
/* a[l] <= P == a[u-1] <= a[u], only need to sort from l+1 to u-2 */
i = l;
j = u-1;
for (;;) { /* invariant: a[l..i] <= P <= a[j..u] */
/* repeat ++i until a[i] >= P */
while (lv_rawgeti(L, 1, ++i), sort_comp(L, -1, -2)) {
if (i>u) lvL_error(L, "invalid order function for sorting");
lv_pop(L, 1); /* remove a[i] */
}
/* repeat --j until a[j] <= P */
while (lv_rawgeti(L, 1, --j), sort_comp(L, -3, -1)) {
if (j<l) lvL_error(L, "invalid order function for sorting");
lv_pop(L, 1); /* remove a[j] */
}
if (j<i) {
lv_pop(L, 3); /* pop pivot, a[i], a[j] */
break;
}
set2(L, i, j);
}
lv_rawgeti(L, 1, u-1);
lv_rawgeti(L, 1, i);
set2(L, u-1, i); /* swap pivot (a[u-1]) with a[i] */
/* a[l..i-1] <= a[i] == P <= a[i+1..u] */
/* adjust so that smaller half is in [j..i] and larger one in [l..u] */
if (i-l < u-i) {
j=l;
i=i-1;
l=i+2;
}
else {
j=i+1;
i=u;
u=j-2;
}
auxsort(L, j, i); /* call recursively the smaller one */
} /* repeat the routine for the larger one */
}
