/*
** QuickSort algorithm (recursive function)
*/
static void auxsort (lua_State *L, IdxT lo, IdxT up,
unsigned int rnd) {
while (lo < up) { /* loop for tail recursion */
IdxT p; /* Pivot index */
IdxT n; /* to be used later */
/* sort elements 'lo', 'p', and 'up' */
lua_geti(L, 1, lo);
lua_geti(L, 1, up);
if (sort_comp(L, -1, -2)) /* a[up] < a[lo]? */
set2(L, lo, up); /* swap a[lo] - a[up] */
else
lua_pop(L, 2); /* remove both values */
if (up - lo == 1) /* only 2 elements? */
return; /* already sorted */
if (up - lo < RANLIMIT || rnd == 0) /* small interval or no randomize? */
p = (lo + up)/2; /* middle element is a good pivot */
else /* for larger intervals, it is worth a random pivot */
p = choosePivot(lo, up, rnd);
lua_geti(L, 1, p);
lua_geti(L, 1, lo);
if (sort_comp(L, -2, -1)) /* a[p] < a[lo]? */
set2(L, p, lo); /* swap a[p] - a[lo] */
else {
lua_pop(L, 1); /* remove a[lo] */
lua_geti(L, 1, up);
if (sort_comp(L, -1, -2)) /* a[up] < a[p]? */
set2(L, p, up); /* swap a[up] - a[p] */
else
lua_pop(L, 2);
}
if (up - lo == 2) /* only 3 elements? */
return; /* already sorted */
lua_geti(L, 1, p); /* get middle element (Pivot) */
lua_pushvalue(L, -1); /* push Pivot */
lua_geti(L, 1, up - 1); /* push a[up - 1] */
set2(L, p, up - 1); /* swap Pivot (a[p]) with a[up - 1] */
p = partition(L, lo, up);
/* a[lo .. p - 1] <= a[p] == P <= a[p + 1 .. up] */
if (p - lo < up - p) { /* lower interval is smaller? */
auxsort(L, lo, p - 1, rnd); /* call recursively for lower interval */
n = p - lo; /* size of smaller interval */
lo = p + 1; /* tail call for [p + 1 .. up] (upper interval) */
}
else {
auxsort(L, p + 1, up, rnd); /* call recursively for upper interval */
n = up - p; /* size of smaller interval */
up = p - 1; /* tail call for [lo .. p - 1] (lower interval) */
}
if ((up - lo) / 128 > n) /* partition too imbalanced? */
rnd = l_randomizePivot(); /* try a new randomization */
} /* tail call auxsort(L, lo, up, rnd) */
}
static int libE_sort (lua_State *L) {
int n = aux_getn(L, 1);
luaL_checkstack(L, 40, ""); /* assume array is smaller than 2^40 */
if (!lua_isnoneornil(L, 2)) /* is there a 2nd argument? */
luaL_checktype(L, 2, LUA_TFUNCTION);
lua_settop(L, 2); /* make sure there is two arguments */
auxsort(L, 1, n);
return 0;
}
static int sort (killa_State *L) {
int n = aux_getn(L, 1) + KILLA_BASE - 1;
killaL_checkstack(L, 40, ""); /* assume array is smaller than 2^40 */
if (!killa_isnoneornull(L, 2)) /* is there a 2nd argument? */
killaL_checktype(L, 2, KILLA_TFUNCTION);
killa_settop(L, 2); /* make sure there is two arguments */
auxsort(L, KILLA_BASE, n);
return 0;
}
static int sort (lua_State *L) {
TabA ta;
int n = (int)aux_getn(L, 1, &ta);
luaL_checkstack(L, 50, ""); /* assume array is smaller than 2^50 */
if (!lua_isnoneornil(L, 2)) /* is there a 2nd argument? */
luaL_checktype(L, 2, LUA_TFUNCTION);
lua_settop(L, 2); /* make sure there are two arguments */
auxsort(L, &ta, 1, n);
return 0;
}
static int luaB_sort (lua_State *L) {
int n;
luaL_checktype(L, 1, LUA_TTABLE);
n = lua_getn(L, 1);
if (!lua_isnull(L, 2)) /* is there a 2nd argument? */
luaL_checktype(L, 2, LUA_TFUNCTION);
lua_settop(L, 2); /* make sure there is two arguments */
auxsort(L, 1, n);
return 0;
}
static int sort (lv_State *L) {
lv_clearFirstTableValue(L);
int n = aux_getn(L, 1);
lvL_checkstack(L, 40, ""); /* assume array is smaller than 2^40 */
if (!lv_isnoneornil(L, 2)) /* is there a 2nd argument? */
lvL_checktype(L, 2, LV_TFUNCTION);
lv_settop(L, 2); /* make sure there is two arguments */
auxsort(L, 1, n);
return 0;
}
static int sort (lua_State *L) {
lua_Integer n = aux_getn(L, 1, TAB_RW);
if (n > 1) { /* non-trivial interval? */
luaL_argcheck(L, n < INT_MAX, 1, "array too big");
if (!lua_isnoneornil(L, 2)) /* is there a 2nd argument? */
luaL_checktype(L, 2, LUA_TFUNCTION); /* must be a function */
lua_settop(L, 2); /* make sure there are two arguments */
auxsort(L, 1, (IdxT)n, 0);
}
return 0;
}
static void luaB_sort (void) {
lua_Object t = lua_getparam(1);
Hash *a = gethash(1);
int n = (int)getnarg(a);
lua_Object func = lua_getparam(2);
luaL_arg_check(func == LUA_NOOBJECT || lua_isfunction(func), 2,
"function expected");
luaD_checkstack(4); /* for Pivot, f, a, b (sort_comp) */
auxsort(a, 1, n, func);
lua_pushobject(t);
}
LUACLLIB_API void luaC_sortlist(lua_State* L, int tabix, int funcix /*=0*/)
{
luaL_checkstack(L, 41, "");
luaL_checktype(L, tabix, LUA_TTABLE);
int t = lua_gettop(L);
int ix = tabix; if (ix < 0) ix = t + (ix + 1);
if (funcix == 0)
lua_pushnil(L);
else
lua_pushvalue(L, funcix);
int n = aux_getn(L, ix);
auxsort(L, 1, n, ix, t + 1);
lua_settop(L, t);
}
static void auxsort (Hash *a, int l, int u, lua_Object f) {
while (l < u) { /* for tail recursion */
TObject *P;
int i, j;
/* sort elements a[l], a[(l+u)/2] and a[u] */
if (sort_comp(f, luaH_getint(a, u), luaH_getint(a, l))) /* a[l]>a[u]? */
swap(a, l, u);
if (u-l == 1) break; /* only 2 elements */
i = (l+u)/2;
P = luaH_getint(a, i);
if (sort_comp(f, P, luaH_getint(a, l))) /* a[l]>a[i]? */
swap(a, l, i);
else if (sort_comp(f, luaH_getint(a, u), P)) /* a[i]>a[u]? */
swap(a, i, u);
if (u-l == 2) break; /* only 3 elements */
P = L->stack.top++;
*P = *luaH_getint(a, i); /* save pivot on stack (for GC) */
swap(a, i, u-1); /* put median element as pivot (a[u-1]) */
/* a[l] <= P == a[u-1] <= a[u], only needs to sort from l+1 to u-2 */
i = l; j = u-1;
for (;;) {
/* invariant: a[l..i] <= P <= a[j..u] */
while (sort_comp(f, luaH_getint(a, ++i), P)) /* stop when a[i] >= P */
if (i>u) lua_error("invalid order function for sorting");
while (sort_comp(f, P, luaH_getint(a, --j))) /* stop when a[j] <= P */
if (j<l) lua_error("invalid order function for sorting");
if (j<i) break;
swap(a, i, j);
}
swap(a, u-1, i); /* swap pivot (a[u-1]) with a[i] */
L->stack.top--; /* remove pivot from stack */
/* 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(a, j, i, f); /* call recursively the smaller one */
} /* repeat the routine for the larger one */
}
static void auxsort (lua_State *L, TabA *ta, int l, int u) {
while (l < u) { /* for tail recursion */
int i, j;
/* sort elements a[l], a[(l+u)/2] and a[u] */
(*ta->geti)(L, 1, l);
(*ta->geti)(L, 1, u);
if (sort_comp(L, -1, -2)) /* a[u] < a[l]? */
set2(L, ta, l, u); /* swap a[l] - a[u] */
else
lua_pop(L, 2);
if (u-l == 1) break; /* only 2 elements */
i = (l+u)/2;
(*ta->geti)(L, 1, i);
(*ta->geti)(L, 1, l);
if (sort_comp(L, -2, -1)) /* a[i]<a[l]? */
set2(L, ta, i, l);
else {
lua_pop(L, 1); /* remove a[l] */
(*ta->geti)(L, 1, u);
if (sort_comp(L, -1, -2)) /* a[u]<a[i]? */
set2(L, ta, i, u);
else
lua_pop(L, 2);
}
if (u-l == 2) break; /* only 3 elements */
(*ta->geti)(L, 1, i); /* Pivot */
lua_pushvalue(L, -1);
(*ta->geti)(L, 1, u-1);
set2(L, ta, 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 ((*ta->geti)(L, 1, ++i), sort_comp(L, -1, -2)) {
if (i>=u) luaL_error(L, "invalid order function for sorting");
lua_pop(L, 1); /* remove a[i] */
}
/* repeat --j until a[j] <= P */
while ((*ta->geti)(L, 1, --j), sort_comp(L, -3, -1)) {
if (j<=l) luaL_error(L, "invalid order function for sorting");
lua_pop(L, 1); /* remove a[j] */
}
if (j<i) {
lua_pop(L, 3); /* pop pivot, a[i], a[j] */
break;
}
set2(L, ta, i, j);
}
(*ta->geti)(L, 1, u-1);
(*ta->geti)(L, 1, i);
set2(L, ta, 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, ta, j, i); /* call recursively the smaller one */
} /* repeat the routine for the larger one */
}
