Mercurial > lxmppd-hg-xmllex / changeset
changeset
util.lsignal: Add lsignal library for catching POSIX signals
Sun, 12 Apr 2009 02:53:50 +0100
- author
- Matthew Wild <mwild1@gmail.com>
- date
- Sun, 12 Apr 2009 02:53:50 +0100
- changeset 988
- 8cb9a0d59e78
- parent 987
- d55ec60331e7
- child 989
- ec239c044f31
util.lsignal: Add lsignal library for catching POSIX signals
| util-src/lsignal.c | file | annotate | diff | comparison | revisions |
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/util-src/lsignal.c Sun Apr 12 02:53:50 2009 +0100 @@ -0,0 +1,387 @@ +/* + * lsignal.h -- Signal Handler Library for Lua + * + * Version: 1.000 + * + * Copyright (C) 2007 Patrick J. Donnelly (batrick@unm.edu) + * + * This software is distributed under the same license as Lua 5.0: + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. +*/ + +#include <signal.h> + +#include "lua.h" +#include "lauxlib.h" + +#ifndef lsig + +#define lsig + +struct lua_signal +{ + char *name; /* name of the signal */ + int sig; /* the signal */ +}; + +#endif + +#define LUA_SIGNAL "lua_signal" + +static const struct lua_signal lua_signals[] = { + /* ANSI C signals */ +#ifdef SIGABRT + {"SIGABRT", SIGABRT}, +#endif +#ifdef SIGFPE + {"SIGFPE", SIGFPE}, +#endif +#ifdef SIGILL + {"SIGILL", SIGILL}, +#endif +#ifdef SIGINT + {"SIGINT", SIGINT}, +#endif +#ifdef SIGSEGV + {"SIGSEGV", SIGSEGV}, +#endif +#ifdef SIGTERM + {"SIGTERM", SIGTERM}, +#endif + /* posix signals */ +#ifdef SIGHUP + {"SIGHUP", SIGHUP}, +#endif +#ifdef SIGQUIT + {"SIGQUIT", SIGQUIT}, +#endif +#ifdef SIGTRAP + {"SIGTRAP", SIGTRAP}, +#endif +#ifdef SIGKILL + {"SIGKILL", SIGKILL}, +#endif +#ifdef SIGUSR1 + {"SIGUSR1", SIGUSR1}, +#endif +#ifdef SIGUSR2 + {"SIGUSR2", SIGUSR2}, +#endif +#ifdef SIGPIPE + {"SIGPIPE", SIGPIPE}, +#endif +#ifdef SIGALRM + {"SIGALRM", SIGALRM}, +#endif +#ifdef SIGCHLD + {"SIGCHLD", SIGCHLD}, +#endif +#ifdef SIGCONT + {"SIGCONT", SIGCONT}, +#endif +#ifdef SIGSTOP + {"SIGSTOP", SIGSTOP}, +#endif +#ifdef SIGTTIN + {"SIGTTIN", SIGTTIN}, +#endif +#ifdef SIGTTOU + {"SIGTTOU", SIGTTOU}, +#endif + /* some BSD signals */ +#ifdef SIGIOT + {"SIGIOT", SIGIOT}, +#endif +#ifdef SIGBUS + {"SIGBUS", SIGBUS}, +#endif +#ifdef SIGCLD + {"SIGCLD", SIGCLD}, +#endif +#ifdef SIGURG + {"SIGURG", SIGURG}, +#endif +#ifdef SIGXCPU + {"SIGXCPU", SIGXCPU}, +#endif +#ifdef SIGXFSZ + {"SIGXFSZ", SIGXFSZ}, +#endif +#ifdef SIGVTALRM + {"SIGVTALRM", SIGVTALRM}, +#endif +#ifdef SIGPROF + {"SIGPROF", SIGPROF}, +#endif +#ifdef SIGWINCH + {"SIGWINCH", SIGWINCH}, +#endif +#ifdef SIGPOLL + {"SIGPOLL", SIGPOLL}, +#endif +#ifdef SIGIO + {"SIGIO", SIGIO}, +#endif + /* add odd signals */ +#ifdef SIGSTKFLT + {"SIGSTKFLT", SIGSTKFLT}, /* stack fault */ +#endif +#ifdef SIGSYS + {"SIGSYS", SIGSYS}, +#endif + {NULL, 0} +}; + +static int Nsig = 0; +static lua_State *Lsig = NULL; +static lua_Hook Hsig = NULL; +static int Hmask = 0; +static int Hcount = 0; + +static void sighook(lua_State *L, lua_Debug *ar) +{ + lua_pushstring(L, LUA_SIGNAL); + lua_gettable(L, LUA_REGISTRYINDEX); + lua_pushnumber(L, Nsig); + lua_gettable(L, -2); + + lua_call(L, 0, 0); + + /* set the old hook */ + lua_sethook(L, Hsig, Hmask, Hcount); +} + +static void handle(int sig) +{ + Hsig = lua_gethook(Lsig); + Hmask = lua_gethookmask(Lsig); + Hcount = lua_gethookcount(Lsig); + Nsig = sig; + + lua_sethook(Lsig, sighook, LUA_MASKCALL | LUA_MASKRET | LUA_MASKCOUNT, 1); + /* + switch (sig) + { + case SIGABRT: ; + case SIGFPE: ; + case SIGILL: ; + case SIGINT: ; + case SIGSEGV: ; + case SIGTERM: ; + } */ +} + +/* + * l_signal == signal(signal [, func [, chook]]) + * + * signal = signal number or string + * func = Lua function to call + * chook = catch within C functions + * if caught, Lua function _must_ + * exit, as the stack is most likely + * in an unstable state. +*/ + +static int l_signal(lua_State *L) +{ + int args = lua_gettop(L); + int t, sig; /* type, signal */ + + /* get type of signal */ + luaL_checkany(L, 1); + t = lua_type(L, 1); + if (t == LUA_TNUMBER) + sig = (int) lua_tonumber(L, 1); + else if (t == LUA_TSTRING) + { + lua_pushstring(L, LUA_SIGNAL); + lua_gettable(L, LUA_REGISTRYINDEX); + lua_pushvalue(L, 1); + lua_gettable(L, -2); + if (!lua_isnumber(L, -1)) + luaL_error(L, "invalid signal string"); + sig = (int) lua_tonumber(L, -1); + lua_pop(L, 1); /* get rid of number we pushed */ + } else + luaL_checknumber(L, 1); /* will always error, with good error msg */ + + /* set handler */ + if (args == 1 || lua_isnil(L, 2)) /* clear handler */ + { + lua_pushstring(L, LUA_SIGNAL); + lua_gettable(L, LUA_REGISTRYINDEX); + lua_pushnumber(L, sig); + lua_gettable(L, -2); /* return old handler */ + lua_pushnumber(L, sig); + lua_pushnil(L); + lua_settable(L, -4); + lua_remove(L, -2); /* remove LUA_SIGNAL table */ + signal(sig, SIG_DFL); + } else + { + luaL_checktype(L, 2, LUA_TFUNCTION); + + lua_pushstring(L, LUA_SIGNAL); + lua_gettable(L, LUA_REGISTRYINDEX); + + lua_pushnumber(L, sig); + lua_pushvalue(L, 2); + lua_settable(L, -3); + + /* Set the state for the handler */ + Lsig = L; + + if (lua_toboolean(L, 3)) /* c hook? */ + { + if (signal(sig, handle) == SIG_ERR) + lua_pushboolean(L, 0); + else + lua_pushboolean(L, 1); + } else /* lua_hook */ + { + if (signal(sig, handle) == SIG_ERR) + lua_pushboolean(L, 0); + else + lua_pushboolean(L, 1); + } + } + return 1; +} + +/* + * l_raise == raise(signal) + * + * signal = signal number or string +*/ + +static int l_raise(lua_State *L) +{ + /* int args = lua_gettop(L); */ + int t = 0; /* type */ + lua_Number ret; + + luaL_checkany(L, 1); + + t = lua_type(L, 1); + if (t == LUA_TNUMBER) + { + ret = (lua_Number) raise((int) lua_tonumber(L, 1)); + lua_pushnumber(L, ret); + } else if (t == LUA_TSTRING) + { + lua_pushstring(L, LUA_SIGNAL); + lua_gettable(L, LUA_REGISTRYINDEX); + lua_pushvalue(L, 1); + lua_gettable(L, -2); + if (!lua_isnumber(L, -1)) + luaL_error(L, "invalid signal string"); + ret = (lua_Number) raise((int) lua_tonumber(L, -1)); + lua_pop(L, 1); /* get rid of number we pushed */ + lua_pushnumber(L, ret); + } else + luaL_checknumber(L, 1); /* will always error, with good error msg */ + + return 1; +} + +#ifdef _POSIX_SOURCE + +/* define some posix only functions */ + +/* + * l_kill == kill(pid, signal) + * + * pid = process id + * signal = signal number or string +*/ + +static int l_kill(lua_State *L) +{ + int t; /* type */ + lua_Number ret; /* return value */ + + luaL_checknumber(L, 1); /* must be int for pid */ + luaL_checkany(L, 2); /* check for a second arg */ + + t = lua_type(L, 2); + if (t == LUA_TNUMBER) + { + ret = (lua_Number) kill((int) lua_tonumber(L, 1), + (int) lua_tonumber(L, 2)); + lua_pushnumber(L, ret); + } else if (t == LUA_TSTRING) + { + lua_pushstring(L, LUA_SIGNAL); + lua_gettable(L, LUA_REGISTRYINDEX); + lua_pushvalue(L, 2); + lua_gettable(L, -2); + if (!lua_isnumber(L, -1)) + luaL_error(L, "invalid signal string"); + ret = (lua_Number) kill((int) lua_tonumber(L, 1), + (int) lua_tonumber(L, -1)); + lua_pop(L, 1); /* get rid of number we pushed */ + lua_pushnumber(L, ret); + } else + luaL_checknumber(L, 2); /* will always error, with good error msg */ + return 1; +} + +#endif + +static const struct luaL_Reg lsignal_lib[] = { + {"signal", l_signal}, + {"raise", l_raise}, +#ifdef _POSIX_SOURCE + {"kill", l_kill}, +#endif + {NULL, NULL} +}; + +int luaopen_util_signal(lua_State *L) +{ + int i = 0; + + /* add the library */ + luaL_register(L, "signal", lsignal_lib); + + /* push lua_signals table into the registry */ + /* put the signals inside the library table too, + * they are only a reference */ + lua_pushstring(L, LUA_SIGNAL); + lua_createtable(L, 0, 0); + + while (lua_signals[i].name != NULL) + { + /* registry table */ + lua_pushstring(L, lua_signals[i].name); + lua_pushnumber(L, lua_signals[i].sig); + lua_settable(L, -3); + /* signal table */ + lua_pushstring(L, lua_signals[i].name); + lua_pushnumber(L, lua_signals[i].sig); + lua_settable(L, -5); + i++; + } + + /* add newtable to the registry */ + lua_settable(L, LUA_REGISTRYINDEX); + + return 1; +}
