mod_posix: Move POSIX signal handling into util.startup to avoid race
When libunbound is initialized, it spawns a thread to work in.
In case a module initializes libunbound, e.g. by triggering a s2s
connection, Prosody would not handle signals, instead immediately quit
on e.g. the reload (SIGHUP) signal. Likely because the libunbound thread
would not have inherited the signal mask from the main Prosody thread.
Thanks Menel, riau and franck-x for reporting and help narrowing down
#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);
}