lauxlib.c
上传用户:yisoukefu
上传日期:2020-08-09
资源大小:39506k
文件大小:17k
- /*
- ** $Id: lauxlib.c,v 1.158 2006/01/16 12:42:21 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_REF 0 /* 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);
- lua_getfield(L, LUA_REGISTRYINDEX, tname); /* get correct metatable */
- if (p == NULL || !lua_getmetatable(L, ud) || !lua_rawequal(L, -1, -2))
- luaL_typerror(L, ud, tname);
- lua_pop(L, 2); /* remove both metatables */
- return p;
- }
- 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", size);
- 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, LUAL_BUFFERSIZE, 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] && lf.f != stdin) { /* binary file? */
- fclose(lf.f);
- lf.f = fopen(filename, "rb"); /* 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 (lf.f != stdin) 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;
- }