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Diffstat (limited to 'src/ltablib.c')
-rw-r--r--src/ltablib.c287
1 files changed, 287 insertions, 0 deletions
diff --git a/src/ltablib.c b/src/ltablib.c
new file mode 100644
index 0000000..b6d9cb4
--- /dev/null
+++ b/src/ltablib.c
@@ -0,0 +1,287 @@
+/*
+** $Id: ltablib.c,v 1.38.1.3 2008/02/14 16:46:58 roberto Exp $
+** Library for Table Manipulation
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stddef.h>
+
+#define ltablib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+#define aux_getn(L,n) (luaL_checktype(L, n, LUA_TTABLE), luaL_getn(L, n))
+
+
+static int foreachi (lua_State *L) {
+ int i;
+ int n = aux_getn(L, 1);
+ luaL_checktype(L, 2, LUA_TFUNCTION);
+ for (i=1; i <= n; i++) {
+ lua_pushvalue(L, 2); /* function */
+ lua_pushinteger(L, i); /* 1st argument */
+ lua_rawgeti(L, 1, i); /* 2nd argument */
+ lua_call(L, 2, 1);
+ if (!lua_isnil(L, -1))
+ return 1;
+ lua_pop(L, 1); /* remove nil result */
+ }
+ return 0;
+}
+
+
+static int foreach (lua_State *L) {
+ luaL_checktype(L, 1, LUA_TTABLE);
+ luaL_checktype(L, 2, LUA_TFUNCTION);
+ lua_pushnil(L); /* first key */
+ while (lua_next(L, 1)) {
+ lua_pushvalue(L, 2); /* function */
+ lua_pushvalue(L, -3); /* key */
+ lua_pushvalue(L, -3); /* value */
+ lua_call(L, 2, 1);
+ if (!lua_isnil(L, -1))
+ return 1;
+ lua_pop(L, 2); /* remove value and result */
+ }
+ return 0;
+}
+
+
+static int maxn (lua_State *L) {
+ lua_Number max = 0;
+ luaL_checktype(L, 1, LUA_TTABLE);
+ lua_pushnil(L); /* first key */
+ while (lua_next(L, 1)) {
+ lua_pop(L, 1); /* remove value */
+ if (lua_type(L, -1) == LUA_TNUMBER) {
+ lua_Number v = lua_tonumber(L, -1);
+ if (v > max) max = v;
+ }
+ }
+ lua_pushnumber(L, max);
+ return 1;
+}
+
+
+static int getn (lua_State *L) {
+ lua_pushinteger(L, aux_getn(L, 1));
+ return 1;
+}
+
+
+static int setn (lua_State *L) {
+ luaL_checktype(L, 1, LUA_TTABLE);
+#ifndef luaL_setn
+ luaL_setn(L, 1, luaL_checkint(L, 2));
+#else
+ luaL_error(L, LUA_QL("setn") " is obsolete");
+#endif
+ lua_pushvalue(L, 1);
+ return 1;
+}
+
+
+static int tinsert (lua_State *L) {
+ int e = aux_getn(L, 1) + 1; /* first empty element */
+ int pos; /* where to insert new element */
+ switch (lua_gettop(L)) {
+ case 2: { /* called with only 2 arguments */
+ pos = e; /* insert new element at the end */
+ break;
+ }
+ case 3: {
+ int i;
+ pos = luaL_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 */
+ lua_rawgeti(L, 1, i-1);
+ lua_rawseti(L, 1, i); /* t[i] = t[i-1] */
+ }
+ break;
+ }
+ default: {
+ return luaL_error(L, "wrong number of arguments to " LUA_QL("insert"));
+ }
+ }
+ luaL_setn(L, 1, e); /* new size */
+ lua_rawseti(L, 1, pos); /* t[pos] = v */
+ return 0;
+}
+
+
+static int tremove (lua_State *L) {
+ int e = aux_getn(L, 1);
+ int pos = luaL_optint(L, 2, e);
+ if (!(1 <= pos && pos <= e)) /* position is outside bounds? */
+ return 0; /* nothing to remove */
+ luaL_setn(L, 1, e - 1); /* t.n = n-1 */
+ lua_rawgeti(L, 1, pos); /* result = t[pos] */
+ for ( ;pos<e; pos++) {
+ lua_rawgeti(L, 1, pos+1);
+ lua_rawseti(L, 1, pos); /* t[pos] = t[pos+1] */
+ }
+ lua_pushnil(L);
+ lua_rawseti(L, 1, e); /* t[e] = nil */
+ return 1;
+}
+
+
+static void addfield (lua_State *L, luaL_Buffer *b, int i) {
+ lua_rawgeti(L, 1, i);
+ if (!lua_isstring(L, -1))
+ luaL_error(L, "invalid value (%s) at index %d in table for "
+ LUA_QL("concat"), luaL_typename(L, -1), i);
+ luaL_addvalue(b);
+}
+
+
+static int tconcat (lua_State *L) {
+ luaL_Buffer b;
+ size_t lsep;
+ int i, last;
+ const char *sep = luaL_optlstring(L, 2, "", &lsep);
+ luaL_checktype(L, 1, LUA_TTABLE);
+ i = luaL_optint(L, 3, 1);
+ last = luaL_opt(L, luaL_checkint, 4, luaL_getn(L, 1));
+ luaL_buffinit(L, &b);
+ for (; i < last; i++) {
+ addfield(L, &b, i);
+ luaL_addlstring(&b, sep, lsep);
+ }
+ if (i == last) /* add last value (if interval was not empty) */
+ addfield(L, &b, i);
+ luaL_pushresult(&b);
+ return 1;
+}
+
+
+
+/*
+** {======================================================
+** Quicksort
+** (based on `Algorithms in MODULA-3', Robert Sedgewick;
+** Addison-Wesley, 1993.)
+*/
+
+
+static void set2 (lua_State *L, int i, int j) {
+ lua_rawseti(L, 1, i);
+ lua_rawseti(L, 1, j);
+}
+
+static int sort_comp (lua_State *L, int a, int b) {
+ if (!lua_isnil(L, 2)) { /* function? */
+ int res;
+ lua_pushvalue(L, 2);
+ lua_pushvalue(L, a-1); /* -1 to compensate function */
+ lua_pushvalue(L, b-2); /* -2 to compensate function and `a' */
+ lua_call(L, 2, 1);
+ res = lua_toboolean(L, -1);
+ lua_pop(L, 1);
+ return res;
+ }
+ else /* a < b? */
+ return lua_lessthan(L, a, b);
+}
+
+static void auxsort (lua_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] */
+ lua_rawgeti(L, 1, l);
+ lua_rawgeti(L, 1, u);
+ if (sort_comp(L, -1, -2)) /* a[u] < a[l]? */
+ set2(L, l, u); /* swap a[l] - a[u] */
+ else
+ lua_pop(L, 2);
+ if (u-l == 1) break; /* only 2 elements */
+ i = (l+u)/2;
+ lua_rawgeti(L, 1, i);
+ lua_rawgeti(L, 1, l);
+ if (sort_comp(L, -2, -1)) /* a[i]<a[l]? */
+ set2(L, i, l);
+ else {
+ lua_pop(L, 1); /* remove a[l] */
+ lua_rawgeti(L, 1, u);
+ if (sort_comp(L, -1, -2)) /* a[u]<a[i]? */
+ set2(L, i, u);
+ else
+ lua_pop(L, 2);
+ }
+ if (u-l == 2) break; /* only 3 elements */
+ lua_rawgeti(L, 1, i); /* Pivot */
+ lua_pushvalue(L, -1);
+ lua_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 (lua_rawgeti(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 (lua_rawgeti(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, i, j);
+ }
+ lua_rawgeti(L, 1, u-1);
+ lua_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 */
+}
+
+static int 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 const luaL_Reg tab_funcs[] = {
+ {"concat", tconcat},
+ {"foreach", foreach},
+ {"foreachi", foreachi},
+ {"getn", getn},
+ {"maxn", maxn},
+ {"insert", tinsert},
+ {"remove", tremove},
+ {"setn", setn},
+ {"sort", sort},
+ {NULL, NULL}
+};
+
+
+LUALIB_API int luaopen_table (lua_State *L) {
+ luaL_register(L, LUA_TABLIBNAME, tab_funcs);
+ return 1;
+}
+