luasocket/src/except.c
2013-05-29 16:56:56 +08:00

102 lines
2.7 KiB
C

/*=========================================================================*\
* Simple exception support
* LuaSocket toolkit
\*=========================================================================*/
#include <stdio.h>
#include "lua.h"
#include "lauxlib.h"
#include "except.h"
/*=========================================================================*\
* Internal function prototypes.
\*=========================================================================*/
static int global_protect(lua_State *L);
static int global_newtry(lua_State *L);
static int protected_(lua_State *L);
static int finalize(lua_State *L);
static int do_nothing(lua_State *L);
/* except functions */
static luaL_Reg func[] = {
{"newtry", global_newtry},
{"protect", global_protect},
{NULL, NULL}
};
/*-------------------------------------------------------------------------*\
* Try factory
\*-------------------------------------------------------------------------*/
static void wrap(lua_State *L) {
lua_newtable(L);
lua_pushnumber(L, 1);
lua_pushvalue(L, -3);
lua_settable(L, -3);
lua_insert(L, -2);
lua_pop(L, 1);
}
static int finalize(lua_State *L) {
if (!lua_toboolean(L, 1)) {
lua_pushvalue(L, lua_upvalueindex(1));
lua_pcall(L, 0, 0, 0);
lua_settop(L, 2);
wrap(L);
lua_error(L);
return 0;
} else return lua_gettop(L);
}
static int do_nothing(lua_State *L) {
(void) L;
return 0;
}
static int global_newtry(lua_State *L) {
lua_settop(L, 1);
if (lua_isnil(L, 1)) lua_pushcfunction(L, do_nothing);
lua_pushcclosure(L, finalize, 1);
return 1;
}
/*-------------------------------------------------------------------------*\
* Protect factory
\*-------------------------------------------------------------------------*/
static int unwrap(lua_State *L) {
if (lua_istable(L, -1)) {
lua_pushnumber(L, 1);
lua_gettable(L, -2);
lua_pushnil(L);
lua_insert(L, -2);
return 1;
} else return 0;
}
static int protected_(lua_State *L) {
lua_pushvalue(L, lua_upvalueindex(1));
lua_insert(L, 1);
if (lua_pcall(L, lua_gettop(L) - 1, LUA_MULTRET, 0) != 0) {
if (unwrap(L)) return 2;
else lua_error(L);
return 0;
} else return lua_gettop(L);
}
static int global_protect(lua_State *L) {
lua_pushcclosure(L, protected_, 1);
return 1;
}
/*-------------------------------------------------------------------------*\
* Init module
\*-------------------------------------------------------------------------*/
int except_open(lua_State *L) {
#if LUA_VERSION_NUM > 501 && !defined(LUA_COMPAT_MODULE)
luaL_setfuncs(L, func, 0);
#else
luaL_openlib(L, NULL, func, 0);
#endif
return 0;
}