File

util-src/table.c @ 13130:0b650a54ff9a

doc/hgrc-email: Example config for using 'hg email' to contribute The initial setup can be tricky if you don't know what and were settings should be added. This should maybe also go into site/doc/contributing
author Kim Alvefur <zash@zash.se>
date Wed, 07 Jun 2023 16:56:53 +0200
parent 12976:a187600ec7d6
line wrap: on
line source

#include <lua.h>
#include <lauxlib.h>

#ifndef LUA_MAXINTEGER
#include <stdint.h>
#define LUA_MAXINTEGER PTRDIFF_MAX
#endif

static int Lcreate_table(lua_State *L) {
	lua_createtable(L, luaL_checkinteger(L, 1), luaL_checkinteger(L, 2));
	return 1;
}

/* COMPAT: w/ Lua pre-5.2 */
static int Lpack(lua_State *L) {
	unsigned int n_args = lua_gettop(L);
	lua_createtable(L, n_args, 1);
	lua_insert(L, 1);

	for(int arg = n_args; arg >= 1; arg--) {
		lua_rawseti(L, 1, arg);
	}

	lua_pushinteger(L, n_args);
	lua_setfield(L, -2, "n");
	return 1;
}

/* COMPAT: w/ Lua pre-5.4 */
static int Lmove (lua_State *L) {
	lua_Integer f = luaL_checkinteger(L, 2);
	lua_Integer e = luaL_checkinteger(L, 3);
	lua_Integer t = luaL_checkinteger(L, 4);

	int tt = !lua_isnoneornil(L, 5) ? 5 : 1;  /* destination table */
	luaL_checktype(L, 1, LUA_TTABLE);
	luaL_checktype(L, tt, LUA_TTABLE);

	if (e >= f) {  /* otherwise, nothing to move */
		lua_Integer n, i;
		luaL_argcheck(L, f > 0 || e < LUA_MAXINTEGER + f, 3,
		  "too many elements to move");
		n = e - f + 1;  /* number of elements to move */
		luaL_argcheck(L, t <= LUA_MAXINTEGER - n + 1, 4,
		"destination wrap around");
		if (t > e || t <= f || (tt != 1 && !lua_compare(L, 1, tt, LUA_OPEQ))) {
			for (i = 0; i < n; i++) {
				lua_rawgeti(L, 1, f + i);
				lua_rawseti(L, tt, t + i);
			}
		} else {
			for (i = n - 1; i >= 0; i--) {
				lua_rawgeti(L, 1, f + i);
				lua_rawseti(L, tt, t + i);
			}
		}
	}

	lua_pushvalue(L, tt);  /* return destination table */
	return 1;
}

int luaopen_prosody_util_table(lua_State *L) {
	luaL_checkversion(L);
	lua_createtable(L, 0, 2);
	lua_pushcfunction(L, Lcreate_table);
	lua_setfield(L, -2, "create");
	lua_pushcfunction(L, Lpack);
	lua_setfield(L, -2, "pack");
	lua_pushcfunction(L, Lmove);
	lua_setfield(L, -2, "move");
	return 1;
}

int luaopen_util_table(lua_State *L) {
	return luaopen_prosody_util_table(L);
}