net.server_epoll: Add support for systemd socket activation
Allows creating listening sockets and accepting client connections
before Prosody starts.
This is unlike normal Prosody dynamic resource management, where ports
may added and removed at any time, and the ports defined by the config.
Weird things happen if these are closed (e.g. due to reload) so here we
prevent closing and ensure sockets are reused when opened again.
#include <lua.h>
#include <lauxlib.h>
static int lc_xpcall (lua_State *L) {
int ret;
int n_arg = lua_gettop(L);
/* f, msgh, p1, p2... */
luaL_argcheck(L, n_arg >= 2, 2, "value expected");
lua_pushvalue(L, 1); /* f to top */
lua_pushvalue(L, 2); /* msgh to top */
lua_replace(L, 1); /* msgh to 1 */
lua_replace(L, 2); /* f to 2 */
/* msgh, f, p1, p2... */
ret = lua_pcall(L, n_arg - 2, LUA_MULTRET, 1);
lua_pushboolean(L, ret == 0);
lua_replace(L, 1);
return lua_gettop(L);
}
int luaopen_prosody_util_compat(lua_State *L) {
lua_createtable(L, 0, 2);
{
lua_pushcfunction(L, lc_xpcall);
lua_setfield(L, -2, "xpcall");
}
return 1;
}
int luaopen_util_compat(lua_State *L) {
return luaopen_prosody_util_compat(L);
}