/*** $Id: lauxlib.c,v 1.159.1.3 2008/01/21 13:20:51 roberto Exp $** Auxiliary functions for building Lua libraries** See Copyright Notice in lua.h*/#include <ctype.h>#include <errno.h>#include <stdarg.h>#include <stdio.h>#include <stdlib.h>#include <string.h>/* This file uses only the official API of Lua.** Any function declared here could be written as an application function.*/#define lauxlib_c#define LUA_LIB#include "lua.h"#include "lauxlib.h"#define FREELIST_REF0/* free list of references *//* convert a stack index to positive */#define abs_index(L, i)((i) > 0 || (i) <= LUA_REGISTRYINDEX ? (i) : \lua_gettop(L) + (i) + 1)/*** {======================================================** Error-report functions** =======================================================*/LUALIB_API int luaL_argerror (lua_State *L, int narg, const char *extramsg) { lua_Debug ar; if (!lua_getstack(L, 0, &ar)) /* no stack frame? */ return luaL_error(L, "bad argument #%d (%s)", narg, extramsg); lua_getinfo(L, "n", &ar); if (strcmp(ar.namewhat, "method") == 0) { narg--; /* do not count `self' */ if (narg == 0) /* error is in the self argument itself? */ return luaL_error(L, "calling " LUA_QS " on bad self (%s)", ar.name, extramsg); } if (ar.name == NULL) ar.name = "?"; return luaL_error(L, "bad argument #%d to " LUA_QS " (%s)", narg, ar.name, extramsg);}LUALIB_API int luaL_typerror (lua_State *L, int narg, const char *tname) { const char *msg = lua_pushfstring(L, "%s expected, got %s", tname, luaL_typename(L, narg)); return luaL_argerror(L, narg, msg);}static void tag_error (lua_State *L, int narg, int tag) { luaL_typerror(L, narg, lua_typename(L, tag));}LUALIB_API void luaL_where (lua_State *L, int level) { lua_Debug ar; if (lua_getstack(L, level, &ar)) { /* check function at level */ lua_getinfo(L, "Sl", &ar); /* get info about it */ if (ar.currentline > 0) { /* is there info? */ lua_pushfstring(L, "%s:%d: ", ar.short_src, ar.currentline); return; } } lua_pushliteral(L, ""); /* else, no information available... */}LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...) { va_list argp; va_start(argp, fmt); luaL_where(L, 1); lua_pushvfstring(L, fmt, argp); va_end(argp); lua_concat(L, 2); return lua_error(L);}/* }====================================================== */LUALIB_API int luaL_checkoption (lua_State *L, int narg, const char *def, const char *const lst[]) { const char *name = (def) ? luaL_optstring(L, narg, def) : luaL_checkstring(L, narg); int i; for (i=0; lst[i]; i++) if (strcmp(lst[i], name) == 0) return i; return luaL_argerror(L, narg, lua_pushfstring(L, "invalid option " LUA_QS, name));}LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) { lua_getfield(L, LUA_REGISTRYINDEX, tname); /* get registry.name */ if (!lua_isnil(L, -1)) /* name already in use? */ return 0; /* leave previous value on top, but return 0 */ lua_pop(L, 1); lua_newtable(L); /* create metatable */ lua_pushvalue(L, -1); lua_setfield(L, LUA_REGISTRYINDEX, tname); /* registry.name = metatable */ return 1;}LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) { void *p = lua_touserdata(L, ud); if (p != NULL) { /* value is a userdata? */ if (lua_getmetatable(L, ud)) { /* does it have a metatable? */ lua_getfield(L, LUA_REGISTRYINDEX, tname); /* get correct metatable */ if (lua_rawequal(L, -1, -2)) { /* does it have the correct mt? */ lua_pop(L, 2); /* remove both metatables */ return p; } } } luaL_typerror(L, ud, tname); /* else error */ return NULL; /* to avoid warnings */}LUALIB_API void luaL_checkstack (lua_State *L, int space, const char *mes) { if (!lua_checkstack(L, space)) luaL_error(L, "stack overflow (%s)", mes);}LUALIB_API void luaL_checktype (lua_State *L, int narg, int t) { if (lua_type(L, narg) != t) tag_error(L, narg, t);}LUALIB_API void luaL_checkany (lua_State *L, int narg) { if (lua_type(L, narg) == LUA_TNONE) luaL_argerror(L, narg, "value expected");}LUALIB_API const char *luaL_checklstring (lua_State *L, int narg, size_t *len) { const char *s = lua_tolstring(L, narg, len); if (!s) tag_error(L, narg, LUA_TSTRING); return s;}LUALIB_API const char *luaL_optlstring (lua_State *L, int narg, const char *def, size_t *len) { if (lua_isnoneornil(L, narg)) { if (len) *len = (def ? strlen(def) : 0); return def; } else return luaL_checklstring(L, narg, len);}LUALIB_API lua_Number luaL_checknumber (lua_State *L, int narg) { lua_Number d = lua_tonumber(L, narg); if (d == 0 && !lua_isnumber(L, narg)) /* avoid extra test when d is not 0 */ tag_error(L, narg, LUA_TNUMBER); return d;}LUALIB_API lua_Number luaL_optnumber (lua_State *L, int narg, lua_Number def) { return luaL_opt(L, luaL_checknumber, narg, def);}LUALIB_API lua_Integer luaL_checkinteger (lua_State *L, int narg) { lua_Integer d = lua_tointeger(L, narg); if (d == 0 && !lua_isnumber(L, narg)) /* avoid extra test when d is not 0 */ tag_error(L, narg, LUA_TNUMBER); return d;}LUALIB_API lua_Integer luaL_optinteger (lua_State *L, int narg, lua_Integer def) { return luaL_opt(L, luaL_checkinteger, narg, def);}LUALIB_API int luaL_getmetafield (lua_State *L, int obj, const char *event) { if (!lua_getmetatable(L, obj)) /* no metatable? */ return 0; lua_pushstring(L, event); lua_rawget(L, -2); if (lua_isnil(L, -1)) { lua_pop(L, 2); /* remove metatable and metafield */ return 0; } else { lua_remove(L, -2); /* remove only metatable */ return 1; }}LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *event) { obj = abs_index(L, obj); if (!luaL_getmetafield(L, obj, event)) /* no metafield? */ return 0; lua_pushvalue(L, obj); lua_call(L, 1, 1); return 1;}LUALIB_API void (luaL_register) (lua_State *L, const char *libname, const luaL_Reg *l) { luaI_openlib(L, libname, l, 0);}static int libsize (const luaL_Reg *l) { int size = 0; for (; l->name; l++) size++; return size;}LUALIB_API void luaI_openlib (lua_State *L, const char *libname, const luaL_Reg *l, int nup) { if (libname) { int size = libsize(l); /* check whether lib already exists */ luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 1); lua_getfield(L, -1, libname); /* get _LOADED[libname] */ if (!lua_istable(L, -1)) { /* not found? */ lua_pop(L, 1); /* remove previous result */ /* try global variable (and create one if it does not exist) */ if (luaL_findtable(L, LUA_GLOBALSINDEX, libname, size) != NULL) luaL_error(L, "name conflict for module " LUA_QS, libname); lua_pushvalue(L, -1); lua_setfield(L, -3, libname); /* _LOADED[libname] = new table */ } lua_remove(L, -2); /* remove _LOADED table */ lua_insert(L, -(nup+1)); /* move library table to below upvalues */ } for (; l->name; l++) { int i; for (i=0; i<nup; i++) /* copy upvalues to the top */ lua_pushvalue(L, -nup); lua_pushcclosure(L, l->func, nup); lua_setfield(L, -(nup+2), l->name); } lua_pop(L, nup); /* remove upvalues */}/*** {======================================================** getn-setn: size for arrays** =======================================================*/#if defined(LUA_COMPAT_GETN)static int checkint (lua_State *L, int topop) { int n = (lua_type(L, -1) == LUA_TNUMBER) ? lua_tointeger(L, -1) : -1; lua_pop(L, topop); return n;}static void getsizes (lua_State *L) { lua_getfield(L, LUA_REGISTRYINDEX, "LUA_SIZES"); if (lua_isnil(L, -1)) { /* no `size' table? */ lua_pop(L, 1); /* remove nil */ lua_newtable(L); /* create it */ lua_pushvalue(L, -1); /* `size' will be its own metatable */ lua_setmetatable(L, -2); lua_pushliteral(L, "kv"); lua_setfield(L, -2, "__mode"); /* metatable(N).__mode = "kv" */ lua_pushvalue(L, -1); lua_setfield(L, LUA_REGISTRYINDEX, "LUA_SIZES"); /* store in register */ }}LUALIB_API void luaL_setn (lua_State *L, int t, int n) { t = abs_index(L, t); lua_pushliteral(L, "n"); lua_rawget(L, t); if (checkint(L, 1) >= 0) { /* is there a numeric field `n'? */ lua_pushliteral(L, "n"); /* use it */ lua_pushinteger(L, n); lua_rawset(L, t); } else { /* use `sizes' */ getsizes(L); lua_pushvalue(L, t); lua_pushinteger(L, n); lua_rawset(L, -3); /* sizes[t] = n */ lua_pop(L, 1); /* remove `sizes' */ }}LUALIB_API int luaL_getn (lua_State *L, int t) { int n; t = abs_index(L, t); lua_pushliteral(L, "n"); /* try t.n */ lua_rawget(L, t); if ((n = checkint(L, 1)) >= 0) return n; getsizes(L); /* else try sizes[t] */ lua_pushvalue(L, t); lua_rawget(L, -2); if ((n = checkint(L, 2)) >= 0) return n; return (int)lua_objlen(L, t);}#endif/* }====================================================== */LUALIB_API const char *luaL_gsub (lua_State *L, const char *s, const char *p, const char *r) { const char *wild; size_t l = strlen(p); luaL_Buffer b; luaL_buffinit(L, &b); while ((wild = strstr(s, p)) != NULL) { luaL_addlstring(&b, s, wild - s); /* push prefix */ luaL_addstring(&b, r); /* push replacement in place of pattern */ s = wild + l; /* continue after `p' */ } luaL_addstring(&b, s); /* push last suffix */ luaL_pushresult(&b); return lua_tostring(L, -1);}LUALIB_API const char *luaL_findtable (lua_State *L, int idx, const char *fname, int szhint) { const char *e; lua_pushvalue(L, idx); do { e = strchr(fname, '.'); if (e == NULL) e = fname + strlen(fname); lua_pushlstring(L, fname, e - fname); lua_rawget(L, -2); if (lua_isnil(L, -1)) { /* no such field? */ lua_pop(L, 1); /* remove this nil */ lua_createtable(L, 0, (*e == '.' ? 1 : szhint)); /* new table for field */ lua_pushlstring(L, fname, e - fname); lua_pushvalue(L, -2); lua_settable(L, -4); /* set new table into field */ } else if (!lua_istable(L, -1)) { /* field has a non-table value? */ lua_pop(L, 2); /* remove table and value */ return fname; /* return problematic part of the name */ } lua_remove(L, -2); /* remove previous table */ fname = e + 1; } while (*e == '.'); return NULL;}/*** {======================================================** Generic Buffer manipulation** =======================================================*/#define bufflen(B)((B)->p - (B)->buffer)#define bufffree(B)((size_t)(LUAL_BUFFERSIZE - bufflen(B)))#define LIMIT(LUA_MINSTACK/2)static int emptybuffer (luaL_Buffer *B) { size_t l = bufflen(B); if (l == 0) return 0; /* put nothing on stack */ else { lua_pushlstring(B->L, B->buffer, l); B->p = B->buffer; B->lvl++; return 1; }}static void adjuststack (luaL_Buffer *B) { if (B->lvl > 1) { lua_State *L = B->L; int toget = 1; /* number of levels to concat */ size_t toplen = lua_strlen(L, -1); do { size_t l = lua_strlen(L, -(toget+1)); if (B->lvl - toget + 1 >= LIMIT || toplen > l) { toplen += l; toget++; } else break; } while (toget < B->lvl); lua_concat(L, toget); B->lvl = B->lvl - toget + 1; }}LUALIB_API char *luaL_prepbuffer (luaL_Buffer *B) { if (emptybuffer(B)) adjuststack(B); return B->buffer;}LUALIB_API void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l) { while (l--) luaL_addchar(B, *s++);}LUALIB_API void luaL_addstring (luaL_Buffer *B, const char *s) { luaL_addlstring(B, s, strlen(s));}LUALIB_API void luaL_pushresult (luaL_Buffer *B) { emptybuffer(B); lua_concat(B->L, B->lvl); B->lvl = 1;}LUALIB_API void luaL_addvalue (luaL_Buffer *B) { lua_State *L = B->L; size_t vl; const char *s = lua_tolstring(L, -1, &vl); if (vl <= bufffree(B)) { /* fit into buffer? */ memcpy(B->p, s, vl); /* put it there */ B->p += vl; lua_pop(L, 1); /* remove from stack */ } else { if (emptybuffer(B)) lua_insert(L, -2); /* put buffer before new value */ B->lvl++; /* add new value into B stack */ adjuststack(B); }}LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) { B->L = L; B->p = B->buffer; B->lvl = 0;}/* }====================================================== */LUALIB_API int luaL_ref (lua_State *L, int t) { int ref; t = abs_index(L, t); if (lua_isnil(L, -1)) { lua_pop(L, 1); /* remove from stack */ return LUA_REFNIL; /* `nil' has a unique fixed reference */ } lua_rawgeti(L, t, FREELIST_REF); /* get first free element */ ref = (int)lua_tointeger(L, -1); /* ref = t[FREELIST_REF] */ lua_pop(L, 1); /* remove it from stack */ if (ref != 0) { /* any free element? */ lua_rawgeti(L, t, ref); /* remove it from list */ lua_rawseti(L, t, FREELIST_REF); /* (t[FREELIST_REF] = t[ref]) */ } else { /* no free elements */ ref = (int)lua_objlen(L, t); ref++; /* create new reference */ } lua_rawseti(L, t, ref); return ref;}LUALIB_API void luaL_unref (lua_State *L, int t, int ref) { if (ref >= 0) { t = abs_index(L, t); lua_rawgeti(L, t, FREELIST_REF); lua_rawseti(L, t, ref); /* t[ref] = t[FREELIST_REF] */ lua_pushinteger(L, ref); lua_rawseti(L, t, FREELIST_REF); /* t[FREELIST_REF] = ref */ }}/*** {======================================================** Load functions** =======================================================*/typedef struct LoadF { int extraline; FILE *f; char buff[LUAL_BUFFERSIZE];} LoadF;static const char *getF (lua_State *L, void *ud, size_t *size) { LoadF *lf = (LoadF *)ud; (void)L; if (lf->extraline) { lf->extraline = 0; *size = 1; return "\n"; } if (feof(lf->f)) return NULL; *size = fread(lf->buff, 1, sizeof(lf->buff), lf->f); return (*size > 0) ? lf->buff : NULL;}static int errfile (lua_State *L, const char *what, int fnameindex) { const char *serr = strerror(errno); const char *filename = lua_tostring(L, fnameindex) + 1; lua_pushfstring(L, "cannot %s %s: %s", what, filename, serr); lua_remove(L, fnameindex); return LUA_ERRFILE;}LUALIB_API int luaL_loadfile (lua_State *L, const char *filename) { LoadF lf; int status, readstatus; int c; int fnameindex = lua_gettop(L) + 1; /* index of filename on the stack */ lf.extraline = 0; if (filename == NULL) { lua_pushliteral(L, "=stdin"); lf.f = stdin; } else { lua_pushfstring(L, "@%s", filename); lf.f = fopen(filename, "r"); if (lf.f == NULL) return errfile(L, "open", fnameindex); } c = getc(lf.f); if (c == '#') { /* Unix exec. file? */ lf.extraline = 1; while ((c = getc(lf.f)) != EOF && c != '\n') ; /* skip first line */ if (c == '\n') c = getc(lf.f); } if (c == LUA_SIGNATURE[0] && filename) { /* binary file? */ lf.f = freopen(filename, "rb", lf.f); /* reopen in binary mode */ if (lf.f == NULL) return errfile(L, "reopen", fnameindex); /* skip eventual `#!...' */ while ((c = getc(lf.f)) != EOF && c != LUA_SIGNATURE[0]) ; lf.extraline = 0; } ungetc(c, lf.f); status = lua_load(L, getF, &lf, lua_tostring(L, -1)); readstatus = ferror(lf.f); if (filename) fclose(lf.f); /* close file (even in case of errors) */ if (readstatus) { lua_settop(L, fnameindex); /* ignore results from `lua_load' */ return errfile(L, "read", fnameindex); } lua_remove(L, fnameindex); return status;}typedef struct LoadS { const char *s; size_t size;} LoadS;static const char *getS (lua_State *L, void *ud, size_t *size) { LoadS *ls = (LoadS *)ud; (void)L; if (ls->size == 0) return NULL; *size = ls->size; ls->size = 0; return ls->s;}LUALIB_API int luaL_loadbuffer (lua_State *L, const char *buff, size_t size, const char *name) { LoadS ls; ls.s = buff; ls.size = size; return lua_load(L, getS, &ls, name);}LUALIB_API int (luaL_loadstring) (lua_State *L, const char *s) { return luaL_loadbuffer(L, s, strlen(s), s);}/* }====================================================== */static void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize) { (void)ud; (void)osize; if (nsize == 0) { free(ptr); return NULL; } else return realloc(ptr, nsize);}static int panic (lua_State *L) { (void)L; /* to avoid warnings */ fprintf(stderr, "PANIC: unprotected error in call to Lua API (%s)\n", lua_tostring(L, -1)); return 0;}LUALIB_API lua_State *luaL_newstate (void) { lua_State *L = lua_newstate(l_alloc, NULL); if (L) lua_atpanic(L, &panic); return L;}
