diff options
Diffstat (limited to 'libs/nixio/src/poll.c')
| -rw-r--r-- | libs/nixio/src/poll.c | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/libs/nixio/src/poll.c b/libs/nixio/src/poll.c new file mode 100644 index 000000000..7a397b96e --- /dev/null +++ b/libs/nixio/src/poll.c @@ -0,0 +1,181 @@ +/* + * 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 <poll.h> +#include <time.h> +#include <errno.h> +#include <stdlib.h> +#include "nixio.h" + + +/** + * nanosleep() + */ +static int nixio_nanosleep(lua_State *L) { + struct timespec req, rem; + req.tv_sec = luaL_optint(L, 1, 0); + req.tv_nsec = luaL_optint(L, 2, 0); + + int status = nanosleep(&req, &rem); + if (!status) { + lua_pushboolean(L, 1); + return 1; + } else { + if (errno == EINTR) { + lua_pushboolean(L, 0); + lua_pushinteger(L, rem.tv_sec); + lua_pushinteger(L, rem.tv_nsec); + return 3; + } else { + return nixio__perror(L); + } + } +} + +/** + * Checks whether a flag is set in the table and translates it into a bitmap + */ +static void nixio_poll_flags__w(lua_State *L, int *map, int f, const char *t) { + lua_pushstring(L, t); + lua_rawget(L, -2); + if (lua_toboolean(L, -1)) { + *map |= f; + } + lua_pop(L, 1); +} + +/** + * Checks whether a flag is set in the bitmap and sets the matching table value + */ +static void nixio_poll_flags__r(lua_State *L, int *map, int f, const char *t) { + lua_pushstring(L, t); + if (*map & f) { + lua_pushboolean(L, 1); + } else { + lua_pushnil(L); + } + lua_rawset(L, -3); +} + +/** + * Translate integer to poll flags and vice versa + */ +static int nixio_poll_flags(lua_State *L) { + int flags; + if (lua_istable(L, 1)) { + lua_settop(L, 1); + flags = 0; + nixio_poll_flags__w(L, &flags, POLLIN, "in"); + nixio_poll_flags__w(L, &flags, POLLPRI, "pri"); + nixio_poll_flags__w(L, &flags, POLLOUT, "out"); + nixio_poll_flags__w(L, &flags, POLLERR, "err"); + nixio_poll_flags__w(L, &flags, POLLHUP, "hup"); + nixio_poll_flags__w(L, &flags, POLLNVAL, "nval"); + lua_pushinteger(L, flags); + } else { + flags = luaL_checkinteger(L, 1); + lua_newtable(L); + nixio_poll_flags__r(L, &flags, POLLIN, "in"); + nixio_poll_flags__r(L, &flags, POLLPRI, "pri"); + nixio_poll_flags__r(L, &flags, POLLOUT, "out"); + nixio_poll_flags__r(L, &flags, POLLERR, "err"); + nixio_poll_flags__r(L, &flags, POLLHUP, "hup"); + nixio_poll_flags__r(L, &flags, POLLNVAL, "nval"); + } + return 1; +} + +/** + * poll({{fd = socket, events = FLAGS}, ...}, timeout) + */ +static int nixio_poll(lua_State *L) { + int len = lua_objlen(L, 1); + int i, fd; + int timeout = luaL_optint(L, 2, 0); + int status = -1; + + /* we are being abused as sleep() replacement... */ + if (lua_isnoneornil(L, 1) || len < 1) { + return nixio__pstatus(L, !poll(NULL, 0, timeout)); + } + + luaL_checktype(L, 1, LUA_TTABLE); + struct pollfd *fds = calloc(len, sizeof(struct pollfd)); + + for (i = 0; i < len; i++) { + lua_rawgeti(L, 1, i+1); + if (!lua_istable(L, -1)) { + free(fds); + return luaL_argerror(L, 1, "invalid datastructure"); + } + + lua_pushliteral(L, "fd"); + lua_rawget(L, -2); + fd = nixio__tofd(L, -1); + if (fd == -1) { + free(fds); + return luaL_argerror(L, 1, "invalid fd in datastructure"); + } + fds[i].fd = fd; + + lua_pushliteral(L, "events"); + lua_rawget(L, -3); + fds[i].events = (short)lua_tointeger(L, -1); + + lua_pop(L, 3); + } + + status = poll(fds, (nfds_t)len, timeout); + + if (status < 1) { + free(fds); + return nixio__perror(L); + } + + for (i = 0; i < len; i++) { + lua_rawgeti(L, 1, i+1); + + lua_pushliteral(L, "revents"); + lua_pushinteger(L, fds[i].revents); + lua_rawset(L, -3); + + lua_pop(L, 1); + } + + free(fds); + + lua_pushinteger(L, status); + lua_pushvalue(L, 1); + + return 2; +} + +/* module table */ +static const luaL_reg R[] = { + {"nanosleep", nixio_nanosleep}, + {"poll", nixio_poll}, + {"poll_flags", nixio_poll_flags}, + {NULL, NULL} +}; + +void nixio_open_poll(lua_State *L) { + luaL_register(L, NULL, R); +} |