1 files changed, 110 insertions, 0 deletions
diff --git a/libs/nixio/src/select.c b/libs/nixio/src/select.c
new file mode 100644
index 0000000000..e88075ce41
--- /dev/null
+++ b/libs/nixio/src/select.c
@@ -0,0 +1,110 @@
+/*
+ * nixio - Linux I/O library for lua
+ *
+ *   Copyright (C) 2009 Steven Barth <steven@midlink.org>
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+#include <lua.h>
+#include <lualib.h>
+#include <lauxlib.h>
+#include <sys/select.h>
+#include "nixio.h"
+
+static int nixio_select(lua_State *L) {
+	int nfds = 0, tmpfd = -1, i = 0, j = 0, o = 0, k, tlen;
+	fd_set rfds, wfds, xfds;
+	fd_set *fdsets[3] = {&rfds, &wfds, &xfds};
+	FD_ZERO(fdsets[0]);
+	FD_ZERO(fdsets[1]);
+	FD_ZERO(fdsets[2]);
+
+	struct timeval timeout;
+	timeout.tv_sec = luaL_optinteger(L, 4, 0);
+	timeout.tv_usec = luaL_optinteger(L, 5, 0);
+
+	/* create fdsets */
+	for (i=0; i<3; i++) {
+		o = i + 1;
+		if (lua_isnoneornil(L, o)) {
+			fdsets[i] = NULL;
+			continue;
+		}
+
+		luaL_checktype(L, o, LUA_TTABLE);
+		tlen = lua_objlen(L, o);
+		luaL_argcheck(L, tlen <= FD_SETSIZE, o, "too many fds");
+
+		for (j=1; j<=tlen; j++) {
+			lua_rawgeti(L, o, j);
+			tmpfd = nixio__checkfd(L, -1);
+			FD_SET(tmpfd, fdsets[i]);
+			if (tmpfd >= nfds) {
+				nfds = tmpfd + 1;
+			}
+			lua_pop(L, 1);
+		}
+	}
+
+	int stat = select(nfds, fdsets[0], fdsets[1], fdsets[2], &timeout);
+
+	if (stat < 0) {
+		return nixio__perror(L);
+	} else if (stat == 0) {
+		lua_pushinteger(L, stat);
+		for (i=1; i<=3; i++) {
+			if (lua_isnoneornil(L, i)) {
+				lua_pushnil(L);
+			} else {
+				lua_newtable(L);
+			}
+		}
+	} else {
+		lua_pushinteger(L, stat);
+
+		/* create return tables */
+		for (i=0; i<3; i++) {
+			o = i + 1;
+			if (lua_isnoneornil(L, o)) {
+				lua_pushnil(L);
+				continue;
+			}
+
+			lua_newtable(L);
+			tlen = lua_objlen(L, o);
+			k = 1;
+
+			for (j=1; j<=tlen; j++) {
+				lua_rawgeti(L, o, j);
+				tmpfd = nixio__tofd(L, -1);
+				if (FD_ISSET(tmpfd, fdsets[i])) {
+					lua_rawseti(L, -2, k++);
+				} else {
+					lua_pop(L, 1);
+				}
+			}
+		}
+	}
+	return 4;
+}
+
+/* module table */
+static const luaL_reg R[] = {
+	{"select",	nixio_select},
+	{NULL,			NULL}
+};
+
+void nixio_open_select(lua_State *L) {
+	luaL_register(L, NULL, R);
+}