/* ** $Id: loadlib.c,v 1.52.1.4 2009/09/09 13:17:16 roberto Exp $ ** Dynamic library loader for Lua ** See Copyright Notice in lua.h ** ** This module contains an implementation of loadlib for Unix systems ** that have dlfcn, an implementation for Darwin (Mac OS X), an ** implementation for Windows, and a stub for other systems. */ #include #include #define loadlib_c #define LUA_LIB #include "lua.h" #include "lauxlib.h" #include "lualib.h" /* prefix for open functions in C libraries */ #define LUA_POF "luaopen_" /* separator for open functions in C libraries */ #define LUA_OFSEP "_" #define LIBPREFIX "LOADLIB: " #define POF LUA_POF #define LIB_FAIL "open" /* error codes for ll_loadfunc */ #define ERRLIB 1 #define ERRFUNC 2 #define setprogdir(L) ((void)0) static void ll_unloadlib (void *lib); static void *ll_load (lua_State *L, const char *path); static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym); #if defined(LUA_DL_DLOPEN) /* ** {======================================================================== ** This is an implementation of loadlib based on the dlfcn interface. ** The dlfcn interface is available in Linux, SunOS, Solaris, IRIX, FreeBSD, ** NetBSD, AIX 4.2, HPUX 11, and probably most other Unix flavors, at least ** as an emulation layer on top of native functions. ** ========================================================================= */ #include static void ll_unloadlib (void *lib) { dlclose(lib); } static void *ll_load (lua_State *L, const char *path) { void *lib = dlopen(path, RTLD_NOW); if (lib == NULL) lua_pushstring(L, dlerror()); return lib; } static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) { lua_CFunction f = (lua_CFunction)dlsym(lib, sym); if (f == NULL) lua_pushstring(L, dlerror()); return f; } /* }====================================================== */ #elif defined(LUA_DL_DLL) /* ** {====================================================================== ** This is an implementation of loadlib for Windows using native functions. ** ======================================================================= */ #include #undef setprogdir static void setprogdir (lua_State *L) { char buff[MAX_PATH + 1]; char *lb; DWORD nsize = sizeof(buff)/sizeof(char); DWORD n = GetModuleFileNameA(NULL, buff, nsize); if (n == 0 || n == nsize || (lb = strrchr(buff, '\\')) == NULL) luaL_error(L, "unable to get ModuleFileName"); else { *lb = '\0'; luaL_gsub(L, lua_tostring(L, -1), LUA_EXECDIR, buff); lua_remove(L, -2); /* remove original string */ } } static void pusherror (lua_State *L) { int error = GetLastError(); char buffer[128]; if (FormatMessageA(FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_FROM_SYSTEM, NULL, error, 0, buffer, sizeof(buffer), NULL)) lua_pushstring(L, buffer); else lua_pushfstring(L, "system error %d\n", error); } static void ll_unloadlib (void *lib) { FreeLibrary((HINSTANCE)lib); } static void *ll_load (lua_State *L, const char *path) { HINSTANCE lib = LoadLibraryA(path); if (lib == NULL) pusherror(L); return lib; } static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) { lua_CFunction f = (lua_CFunction)GetProcAddress((HINSTANCE)lib, sym); if (f == NULL) pusherror(L); return f; } /* }====================================================== */ #elif defined(LUA_DL_DYLD) /* ** {====================================================================== ** Native Mac OS X / Darwin Implementation ** ======================================================================= */ #include /* Mac appends a `_' before C function names */ #undef POF #define POF "_" LUA_POF static void pusherror (lua_State *L) { const char *err_str; const char *err_file; NSLinkEditErrors err; int err_num; NSLinkEditError(&err, &err_num, &err_file, &err_str); lua_pushstring(L, err_str); } static const char *errorfromcode (NSObjectFileImageReturnCode ret) { switch (ret) { case NSObjectFileImageInappropriateFile: return "file is not a bundle"; case NSObjectFileImageArch: return "library is for wrong CPU type"; case NSObjectFileImageFormat: return "bad format"; case NSObjectFileImageAccess: return "cannot access file"; case NSObjectFileImageFailure: default: return "unable to load library"; } } static void ll_unloadlib (void *lib) { NSUnLinkModule((NSModule)lib, NSUNLINKMODULE_OPTION_RESET_LAZY_REFERENCES); } static void *ll_load (lua_State *L, const char *path) { NSObjectFileImage img; NSObjectFileImageReturnCode ret; /* this would be a rare case, but prevents crashing if it happens */ if(!_dyld_present()) { lua_pushliteral(L, "dyld not present"); return NULL; } ret = NSCreateObjectFileImageFromFile(path, &img); if (ret == NSObjectFileImageSuccess) { NSModule mod = NSLinkModule(img, path, NSLINKMODULE_OPTION_PRIVATE | NSLINKMODULE_OPTION_RETURN_ON_ERROR); NSDestroyObjectFileImage(img); if (mod == NULL) pusherror(L); return mod; } lua_pushstring(L, errorfromcode(ret)); return NULL; } static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) { NSSymbol nss = NSLookupSymbolInModule((NSModule)lib, sym); if (nss == NULL) { lua_pushfstring(L, "symbol " LUA_QS " not found", sym); return NULL; } return (lua_CFunction)NSAddressOfSymbol(nss); } /* }====================================================== */ #else /* ** {====================================================== ** Fallback for other systems ** ======================================================= */ #undef LIB_FAIL #define LIB_FAIL "absent" #define DLMSG "dynamic libraries not enabled; check your Lua installation" static void ll_unloadlib (void *lib) { (void)lib; /* to avoid warnings */ } static void *ll_load (lua_State *L, const char *path) { (void)path; /* to avoid warnings */ lua_pushliteral(L, DLMSG); return NULL; } static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) { (void)lib; (void)sym; /* to avoid warnings */ lua_pushliteral(L, DLMSG); return NULL; } /* }====================================================== */ #endif static void **ll_register (lua_State *L, const char *path) { void **plib; lua_pushfstring(L, "%s%s", LIBPREFIX, path); lua_gettable(L, LUA_REGISTRYINDEX); /* check library in registry? */ if (!lua_isnil(L, -1)) /* is there an entry? */ plib = (void **)lua_touserdata(L, -1); else { /* no entry yet; create one */ lua_pop(L, 1); plib = (void **)lua_newuserdata(L, sizeof(const void *)); *plib = NULL; luaL_getmetatable(L, "_LOADLIB"); lua_setmetatable(L, -2); lua_pushfstring(L, "%s%s", LIBPREFIX, path); lua_pushvalue(L, -2); lua_settable(L, LUA_REGISTRYINDEX); } return plib; } /* ** __gc tag method: calls library's `ll_unloadlib' function with the lib ** handle */ static int gctm (lua_State *L) { void **lib = (void **)luaL_checkudata(L, 1, "_LOADLIB"); if (*lib) ll_unloadlib(*lib); *lib = NULL; /* mark library as closed */ return 0; } static int ll_loadfunc (lua_State *L, const char *path, const char *sym) { void **reg = ll_register(L, path); if (*reg == NULL) *reg = ll_load(L, path); if (*reg == NULL) return ERRLIB; /* unable to load library */ else { lua_CFunction f = ll_sym(L, *reg, sym); if (f == NULL) return ERRFUNC; /* unable to find function */ lua_pushcfunction(L, f); return 0; /* return function */ } } static int ll_loadlib (lua_State *L) { const char *path = luaL_checkstring(L, 1); const char *init = luaL_checkstring(L, 2); int stat = ll_loadfunc(L, path, init); if (stat == 0) /* no errors? */ return 1; /* return the loaded function */ else { /* error; error message is on stack top */ lua_pushnil(L); lua_insert(L, -2); lua_pushstring(L, (stat == ERRLIB) ? LIB_FAIL : "init"); return 3; /* return nil, error message, and where */ } } /* ** {====================================================== ** 'require' function ** ======================================================= */ static int readable (const char *filename) { FILE *f = fopen(filename, "r"); /* try to open file */ if (f == NULL) return 0; /* open failed */ fclose(f); return 1; } static const char *pushnexttemplate (lua_State *L, const char *path) { const char *l; while (*path == *LUA_PATHSEP) path++; /* skip separators */ if (*path == '\0') return NULL; /* no more templates */ l = strchr(path, *LUA_PATHSEP); /* find next separator */ if (l == NULL) l = path + strlen(path); lua_pushlstring(L, path, l - path); /* template */ return l; } static const char *findfile (lua_State *L, const char *name, const char *pname) { const char *path; name = luaL_gsub(L, name, ".", LUA_DIRSEP); lua_getfield(L, LUA_ENVIRONINDEX, pname); path = lua_tostring(L, -1); if (path == NULL) luaL_error(L, LUA_QL("package.%s") " must be a string", pname); lua_pushliteral(L, ""); /* error accumulator */ while ((path = pushnexttemplate(L, path)) != NULL) { const char *filename; filename = luaL_gsub(L, lua_tostring(L, -1), LUA_PATH_MARK, name); lua_remove(L, -2); /* remove path template */ if (readable(filename)) /* does file exist and is readable? */ return filename; /* return that file name */ lua_pushfstring(L, "\n\tno file " LUA_QS, filename); lua_remove(L, -2); /* remove file name */ lua_concat(L, 2); /* add entry to possible error message */ } return NULL; /* not found */ } static void loaderror (lua_State *L, const char *filename) { luaL_error(L, "error loading module " LUA_QS " from file " LUA_QS ":\n\t%s", lua_tostring(L, 1), filename, lua_tostring(L, -1)); } static int loader_Lua (lua_State *L) { const char *filename; const char *name = luaL_checkstring(L, 1); filename = findfile(L, name, "path"); if (filename == NULL) return 1; /* library not found in this path */ if (luaL_loadfile(L, filename) != 0) loaderror(L, filename); return 1; /* library loaded successfully */ } static const char *mkfuncname (lua_State *L, const char *modname) { const char *funcname; const char *mark = strchr(modname, *LUA_IGMARK); if (mark) modname = mark + 1; funcname = luaL_gsub(L, modname, ".", LUA_OFSEP); funcname = lua_pushfstring(L, POF"%s
# getwtxt [![Build Status](https://travis-ci.com/getwtxt/getwtxt.svg?branch=master)](https://travis-ci.com/getwtxt/getwtxt)

twtxt registry written in Go! 

* Easy to set up and maintain. 
* Uses an in-memory cache to serve requests.
* Pushes to `LevelDB` at a configurable interval for data storage. 
* Run directly facing the internet or behind `Caddy` / `nginx`.

## Development Progress

`ETA` 31 May 2019


* [x] Types and Config
* [x] HTTP Routing
* [x] Registry Manipulation ([getwtxt/registry](https://github.com/getwtxt/registry))
* [x] Request Handling
* [x] Cache Management
* [x] Persistent Data Storage
* [ ] Refactor / Test / Debug
* [ ] Documentation

## Notes

* twtxt
  * [twtxt.readthedocs.io](https://twtxt.readthedocs.io)
package (lua_State *L) { int i; /* create new type _LOADLIB */ luaL_newmetatable(L, "_LOADLIB"); lua_pushcfunction(L, gctm); lua_setfield(L, -2, "__gc"); /* create `package' table */ luaL_register(L, LUA_LOADLIBNAME, pk_funcs); #if defined(LUA_COMPAT_LOADLIB) lua_getfield(L, -1, "loadlib"); lua_setfield(L, LUA_GLOBALSINDEX, "loadlib"); #endif lua_pushvalue(L, -1); lua_replace(L, LUA_ENVIRONINDEX); /* create `loaders' table */ lua_createtable(L, sizeof(loaders)/sizeof(loaders[0]) - 1, 0); /* fill it with pre-defined loaders */ for (i=0; loaders[i] != NULL; i++) { lua_pushcfunction(L, loaders[i]); lua_rawseti(L, -2, i+1); } lua_setfield(L, -2, "loaders"); /* put it in field `loaders' */ setpath(L, "path", LUA_PATH, LUA_PATH_DEFAULT); /* set field `path' */ setpath(L, "cpath", LUA_CPATH, LUA_CPATH_DEFAULT); /* set field `cpath' */ /* store config information */ lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATHSEP "\n" LUA_PATH_MARK "\n" LUA_EXECDIR "\n" LUA_IGMARK); lua_setfield(L, -2, "config"); /* set field `loaded' */ luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 2); lua_setfield(L, -2, "loaded"); /* set field `preload' */ lua_newtable(L); lua_setfield(L, -2, "preload"); lua_pushvalue(L, LUA_GLOBALSINDEX); luaL_register(L, NULL, ll_funcs); /* open lib into global table */ lua_pop(L, 1); return 1; /* return 'package' table */ }