commit af4721f7a37834e5b5469f342caed0629932a4aa
parent 018e50ad7f24aa8f8f4afe50d513964624c4ca35
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Tue, 9 Apr 2002 17:18:44 -0300
library with table manipulation functions
Diffstat:
| A | ltablib.c | | | 308 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
1 file changed, 308 insertions(+), 0 deletions(-)
diff --git a/ltablib.c b/ltablib.c
@@ -0,0 +1,308 @@
+/*
+** $Id: $
+** Library for Table Manipulation
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stddef.h>
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "luadebug.h"
+#include "lualib.h"
+
+
+
+
+static int luaB_foreachi (lua_State *L) {
+ int n, i;
+ luaL_check_type(L, 1, LUA_TTABLE);
+ luaL_check_type(L, 2, LUA_TFUNCTION);
+ n = lua_getn(L, 1);
+ for (i=1; i<=n; i++) {
+ lua_pushvalue(L, 2); /* function */
+ lua_pushnumber(L, i); /* 1st argument */
+ lua_rawgeti(L, 1, i); /* 2nd argument */
+ lua_rawcall(L, 2, 1);
+ if (!lua_isnil(L, -1))
+ return 1;
+ lua_pop(L, 1); /* remove nil result */
+ }
+ return 0;
+}
+
+
+static int luaB_foreach (lua_State *L) {
+ luaL_check_type(L, 1, LUA_TTABLE);
+ luaL_check_type(L, 2, LUA_TFUNCTION);
+ lua_pushnil(L); /* first key */
+ for (;;) {
+ if (lua_next(L, 1) == 0)
+ return 0;
+ lua_pushvalue(L, 2); /* function */
+ lua_pushvalue(L, -3); /* key */
+ lua_pushvalue(L, -3); /* value */
+ lua_rawcall(L, 2, 1);
+ if (!lua_isnil(L, -1))
+ return 1;
+ lua_pop(L, 2); /* remove value and result */
+ }
+}
+
+
+static void aux_setn (lua_State *L, int t, int n) {
+ lua_pushliteral(L, "n");
+ lua_pushnumber(L, n);
+ lua_rawset(L, t);
+}
+
+
+static int luaB_getn (lua_State *L) {
+ luaL_check_type(L, 1, LUA_TTABLE);
+ lua_pushnumber(L, lua_getn(L, 1));
+ return 1;
+}
+
+
+static int luaB_tinsert (lua_State *L) {
+ int v = lua_gettop(L); /* number of arguments */
+ int n, pos;
+ luaL_check_type(L, 1, LUA_TTABLE);
+ n = lua_getn(L, 1);
+ if (v == 2) /* called with only 2 arguments */
+ pos = n+1;
+ else {
+ v = 3; /* function may be called with more than 3 args */
+ pos = luaL_check_int(L, 2); /* 2nd argument is the position */
+ }
+ if (pos > n+1) n = pos-1;
+ aux_setn(L, 1, n+1); /* t.n = n+1 */
+ for (; n>=pos; n--) {
+ lua_rawgeti(L, 1, n);
+ lua_rawseti(L, 1, n+1); /* t[n+1] = t[n] */
+ }
+ lua_pushvalue(L, v);
+ lua_rawseti(L, 1, pos); /* t[pos] = v */
+ return 0;
+}
+
+
+static int luaB_tremove (lua_State *L) {
+ int pos, n;
+ luaL_check_type(L, 1, LUA_TTABLE);
+ n = lua_getn(L, 1);
+ pos = luaL_opt_int(L, 2, n);
+ if (n <= 0) return 0; /* table is `empty' */
+ aux_setn(L, 1, n-1); /* t.n = n-1 */
+ lua_rawgeti(L, 1, pos); /* result = t[pos] */
+ for ( ;pos<n; pos++) {
+ lua_rawgeti(L, 1, pos+1);
+ lua_rawseti(L, 1, pos); /* a[pos] = a[pos+1] */
+ }
+ lua_pushnil(L);
+ lua_rawseti(L, 1, n); /* t[n] = nil */
+ 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) {
+ /* WARNING: the caller (auxsort) must ensure stack space */
+ if (!lua_isnoneornil(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_rawcall(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) lua_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) lua_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 luaB_sort (lua_State *L) {
+ int n;
+ luaL_check_type(L, 1, LUA_TTABLE);
+ n = lua_getn(L, 1);
+ if (!lua_isnone(L, 2)) /* is there a 2nd argument? */
+ luaL_check_type(L, 2, LUA_TFUNCTION);
+ lua_settop(L, 2); /* make sure there is two arguments */
+ auxsort(L, 1, n);
+ return 0;
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Coroutine library
+** =======================================================
+*/
+
+
+static int luaB_resume (lua_State *L) {
+ lua_State *co = (lua_State *)lua_getfrombox(L, lua_upvalueindex(1));
+ lua_settop(L, 0);
+ if (lua_resume(L, co) != 0)
+ lua_error(L, "error running co-routine");
+ return lua_gettop(L);
+}
+
+
+
+static int gc_coroutine (lua_State *L) {
+ lua_State *co = (lua_State *)lua_getfrombox(L, 1);
+ lua_closethread(L, co);
+ return 0;
+}
+
+
+static int luaB_coroutine (lua_State *L) {
+ lua_State *NL;
+ int ref;
+ int i;
+ int n = lua_gettop(L);
+ luaL_arg_check(L, lua_isfunction(L, 1) && !lua_iscfunction(L, 1), 1,
+ "Lua function expected");
+ NL = lua_newthread(L);
+ if (NL == NULL) lua_error(L, "unable to create new thread");
+ /* move function and arguments from L to NL */
+ for (i=0; i<n; i++) {
+ ref = lua_ref(L, 1);
+ lua_getref(NL, ref);
+ lua_insert(NL, 1);
+ lua_unref(L, ref);
+ }
+ lua_cobegin(NL, n-1);
+ lua_newpointerbox(L, NL);
+ lua_pushliteral(L, "Coroutine");
+ lua_rawget(L, LUA_REGISTRYINDEX);
+ lua_setmetatable(L, -2);
+ lua_pushcclosure(L, luaB_resume, 1);
+ return 1;
+}
+
+
+static int luaB_yield (lua_State *L) {
+ return lua_yield(L, lua_gettop(L));
+}
+
+static const luaL_reg co_funcs[] = {
+ {"create", luaB_coroutine},
+ {"yield", luaB_yield},
+ {NULL, NULL}
+};
+
+
+static void co_open (lua_State *L) {
+ luaL_opennamedlib(L, "co", co_funcs, 0);
+ /* create metatable for coroutines */
+ lua_pushliteral(L, "Coroutine");
+ lua_newtable(L);
+ lua_pushliteral(L, "__gc");
+ lua_pushcfunction(L, gc_coroutine);
+ lua_rawset(L, -3);
+ lua_rawset(L, LUA_REGISTRYINDEX);
+}
+
+/* }====================================================== */
+
+
+static const luaL_reg tab_funcs[] = {
+ {"foreach", luaB_foreach},
+ {"foreachi", luaB_foreachi},
+ {"getn", luaB_getn},
+ {"sort", luaB_sort},
+ {"insert", luaB_tinsert},
+ {"remove", luaB_tremove},
+ {NULL, NULL}
+};
+
+
+LUALIB_API int lua_tablibopen (lua_State *L) {
+ luaL_opennamedlib(L, "tab", tab_funcs, 0);
+ co_open(L);
+ return 0;
+}
+
