123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770771772773774775776777778779780781782783784785786787788789790791792793794795796797798799800801802803804805806807808809810811812813814815816817818819820821822823824825826827828829830831832833834835836837838839840841842843844845846847848849850851852853854855856857858859860861862863864865866867868869870871872873874875876877878879880881882883884885886887888889890891892893894895896897898899900901902903904905906907908909910911912913914915916917918919920921922923924925926927928929930931932933934935936937938939940941942943944945946947948949950951952953954955956957958959960961962963964965966967968969970971972973974975976977978979980981982983984985986987988989990991992993994995996997998999100010011002100310041005100610071008100910101011101210131014101510161017101810191020102110221023102410251026102710281029103010311032103310341035103610371038103910401041104210431044104510461047104810491050105110521053105410551056105710581059106010611062106310641065106610671068106910701071107210731074107510761077107810791080108110821083 |
- /*
- ** $Id: lauxlib.c $
- ** Auxiliary functions for building Lua libraries
- ** See Copyright Notice in lua.h
- */
- #define lauxlib_c
- #define LUA_LIB
- #include "lprefix.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.
- */
- #include "lua.h"
- #include "lauxlib.h"
- #if !defined(MAX_SIZET)
- /* maximum value for size_t */
- #define MAX_SIZET ((size_t)(~(size_t)0))
- #endif
- /*
- ** {======================================================
- ** Traceback
- ** =======================================================
- */
- #define LEVELS1 10 /* size of the first part of the stack */
- #define LEVELS2 11 /* size of the second part of the stack */
- /*
- ** Search for 'objidx' in table at index -1. ('objidx' must be an
- ** absolute index.) Return 1 + string at top if it found a good name.
- */
- static int findfield (lua_State *L, int objidx, int level) {
- if (level == 0 || !lua_istable(L, -1))
- return 0; /* not found */
- lua_pushnil(L); /* start 'next' loop */
- while (lua_next(L, -2)) { /* for each pair in table */
- if (lua_type(L, -2) == LUA_TSTRING) { /* ignore non-string keys */
- if (lua_rawequal(L, objidx, -1)) { /* found object? */
- lua_pop(L, 1); /* remove value (but keep name) */
- return 1;
- }
- else if (findfield(L, objidx, level - 1)) { /* try recursively */
- /* stack: lib_name, lib_table, field_name (top) */
- lua_pushliteral(L, "."); /* place '.' between the two names */
- lua_replace(L, -3); /* (in the slot occupied by table) */
- lua_concat(L, 3); /* lib_name.field_name */
- return 1;
- }
- }
- lua_pop(L, 1); /* remove value */
- }
- return 0; /* not found */
- }
- /*
- ** Search for a name for a function in all loaded modules
- */
- static int pushglobalfuncname (lua_State *L, lua_Debug *ar) {
- int top = lua_gettop(L);
- lua_getinfo(L, "f", ar); /* push function */
- lua_getfield(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE);
- if (findfield(L, top + 1, 2)) {
- const char *name = lua_tostring(L, -1);
- if (strncmp(name, LUA_GNAME ".", 3) == 0) { /* name start with '_G.'? */
- lua_pushstring(L, name + 3); /* push name without prefix */
- lua_remove(L, -2); /* remove original name */
- }
- lua_copy(L, -1, top + 1); /* copy name to proper place */
- lua_settop(L, top + 1); /* remove table "loaded" and name copy */
- return 1;
- }
- else {
- lua_settop(L, top); /* remove function and global table */
- return 0;
- }
- }
- static void pushfuncname (lua_State *L, lua_Debug *ar) {
- if (pushglobalfuncname(L, ar)) { /* try first a global name */
- lua_pushfstring(L, "function '%s'", lua_tostring(L, -1));
- lua_remove(L, -2); /* remove name */
- }
- else if (*ar->namewhat != '\0') /* is there a name from code? */
- lua_pushfstring(L, "%s '%s'", ar->namewhat, ar->name); /* use it */
- else if (*ar->what == 'm') /* main? */
- lua_pushliteral(L, "main chunk");
- else if (*ar->what != 'C') /* for Lua functions, use <file:line> */
- lua_pushfstring(L, "function <%s:%d>", ar->short_src, ar->linedefined);
- else /* nothing left... */
- lua_pushliteral(L, "?");
- }
- static int lastlevel (lua_State *L) {
- lua_Debug ar;
- int li = 1, le = 1;
- /* find an upper bound */
- while (lua_getstack(L, le, &ar)) { li = le; le *= 2; }
- /* do a binary search */
- while (li < le) {
- int m = (li + le)/2;
- if (lua_getstack(L, m, &ar)) li = m + 1;
- else le = m;
- }
- return le - 1;
- }
- LUALIB_API void luaL_traceback (lua_State *L, lua_State *L1,
- const char *msg, int level) {
- luaL_Buffer b;
- lua_Debug ar;
- int last = lastlevel(L1);
- int limit2show = (last - level > LEVELS1 + LEVELS2) ? LEVELS1 : -1;
- luaL_buffinit(L, &b);
- if (msg) {
- luaL_addstring(&b, msg);
- luaL_addchar(&b, '\n');
- }
- luaL_addstring(&b, "stack traceback:");
- while (lua_getstack(L1, level++, &ar)) {
- if (limit2show-- == 0) { /* too many levels? */
- int n = last - level - LEVELS2 + 1; /* number of levels to skip */
- lua_pushfstring(L, "\n\t...\t(skipping %d levels)", n);
- luaL_addvalue(&b); /* add warning about skip */
- level += n; /* and skip to last levels */
- }
- else {
- lua_getinfo(L1, "Slnt", &ar);
- if (ar.currentline <= 0)
- lua_pushfstring(L, "\n\t%s: in ", ar.short_src);
- else
- lua_pushfstring(L, "\n\t%s:%d: in ", ar.short_src, ar.currentline);
- luaL_addvalue(&b);
- pushfuncname(L, &ar);
- luaL_addvalue(&b);
- if (ar.istailcall)
- luaL_addstring(&b, "\n\t(...tail calls...)");
- }
- }
- luaL_pushresult(&b);
- }
- /* }====================================================== */
- /*
- ** {======================================================
- ** Error-report functions
- ** =======================================================
- */
- LUALIB_API int luaL_argerror (lua_State *L, int arg, const char *extramsg) {
- lua_Debug ar;
- if (!lua_getstack(L, 0, &ar)) /* no stack frame? */
- return luaL_error(L, "bad argument #%d (%s)", arg, extramsg);
- lua_getinfo(L, "n", &ar);
- if (strcmp(ar.namewhat, "method") == 0) {
- arg--; /* do not count 'self' */
- if (arg == 0) /* error is in the self argument itself? */
- return luaL_error(L, "calling '%s' on bad self (%s)",
- ar.name, extramsg);
- }
- if (ar.name == NULL)
- ar.name = (pushglobalfuncname(L, &ar)) ? lua_tostring(L, -1) : "?";
- return luaL_error(L, "bad argument #%d to '%s' (%s)",
- arg, ar.name, extramsg);
- }
- int luaL_typeerror (lua_State *L, int arg, const char *tname) {
- const char *msg;
- const char *typearg; /* name for the type of the actual argument */
- if (luaL_getmetafield(L, arg, "__name") == LUA_TSTRING)
- typearg = lua_tostring(L, -1); /* use the given type name */
- else if (lua_type(L, arg) == LUA_TLIGHTUSERDATA)
- typearg = "light userdata"; /* special name for messages */
- else
- typearg = luaL_typename(L, arg); /* standard name */
- msg = lua_pushfstring(L, "%s expected, got %s", tname, typearg);
- return luaL_argerror(L, arg, msg);
- }
- static void tag_error (lua_State *L, int arg, int tag) {
- luaL_typeerror(L, arg, lua_typename(L, tag));
- }
- /*
- ** The use of 'lua_pushfstring' ensures this function does not
- ** need reserved stack space when called.
- */
- 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_pushfstring(L, ""); /* else, no information available... */
- }
- /*
- ** Again, the use of 'lua_pushvfstring' ensures this function does
- ** not need reserved stack space when called. (At worst, it generates
- ** an error with "stack overflow" instead of the given message.)
- */
- 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_fileresult (lua_State *L, int stat, const char *fname) {
- int en = errno; /* calls to Lua API may change this value */
- if (stat) {
- lua_pushboolean(L, 1);
- return 1;
- }
- else {
- luaL_pushfail(L);
- if (fname)
- lua_pushfstring(L, "%s: %s", fname, strerror(en));
- else
- lua_pushstring(L, strerror(en));
- lua_pushinteger(L, en);
- return 3;
- }
- }
- #if !defined(l_inspectstat) /* { */
- #if defined(LUA_USE_POSIX)
- #include <sys/wait.h>
- /*
- ** use appropriate macros to interpret 'pclose' return status
- */
- #define l_inspectstat(stat,what) \
- if (WIFEXITED(stat)) { stat = WEXITSTATUS(stat); } \
- else if (WIFSIGNALED(stat)) { stat = WTERMSIG(stat); what = "signal"; }
- #else
- #define l_inspectstat(stat,what) /* no op */
- #endif
- #endif /* } */
- LUALIB_API int luaL_execresult (lua_State *L, int stat) {
- if (stat != 0 && errno != 0) /* error with an 'errno'? */
- return luaL_fileresult(L, 0, NULL);
- else {
- const char *what = "exit"; /* type of termination */
- l_inspectstat(stat, what); /* interpret result */
- if (*what == 'e' && stat == 0) /* successful termination? */
- lua_pushboolean(L, 1);
- else
- luaL_pushfail(L);
- lua_pushstring(L, what);
- lua_pushinteger(L, stat);
- return 3; /* return true/fail,what,code */
- }
- }
- /* }====================================================== */
- /*
- ** {======================================================
- ** Userdata's metatable manipulation
- ** =======================================================
- */
- LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) {
- if (luaL_getmetatable(L, tname) != LUA_TNIL) /* name already in use? */
- return 0; /* leave previous value on top, but return 0 */
- lua_pop(L, 1);
- lua_createtable(L, 0, 2); /* create metatable */
- lua_pushstring(L, tname);
- lua_setfield(L, -2, "__name"); /* metatable.__name = tname */
- lua_pushvalue(L, -1);
- lua_setfield(L, LUA_REGISTRYINDEX, tname); /* registry.name = metatable */
- return 1;
- }
- LUALIB_API void luaL_setmetatable (lua_State *L, const char *tname) {
- luaL_getmetatable(L, tname);
- lua_setmetatable(L, -2);
- }
- LUALIB_API void *luaL_testudata (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? */
- luaL_getmetatable(L, tname); /* get correct metatable */
- if (!lua_rawequal(L, -1, -2)) /* not the same? */
- p = NULL; /* value is a userdata with wrong metatable */
- lua_pop(L, 2); /* remove both metatables */
- return p;
- }
- }
- return NULL; /* value is not a userdata with a metatable */
- }
- LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) {
- void *p = luaL_testudata(L, ud, tname);
- luaL_argexpected(L, p != NULL, ud, tname);
- return p;
- }
- /* }====================================================== */
- /*
- ** {======================================================
- ** Argument check functions
- ** =======================================================
- */
- LUALIB_API int luaL_checkoption (lua_State *L, int arg, const char *def,
- const char *const lst[]) {
- const char *name = (def) ? luaL_optstring(L, arg, def) :
- luaL_checkstring(L, arg);
- int i;
- for (i=0; lst[i]; i++)
- if (strcmp(lst[i], name) == 0)
- return i;
- return luaL_argerror(L, arg,
- lua_pushfstring(L, "invalid option '%s'", name));
- }
- /*
- ** Ensures the stack has at least 'space' extra slots, raising an error
- ** if it cannot fulfill the request. (The error handling needs a few
- ** extra slots to format the error message. In case of an error without
- ** this extra space, Lua will generate the same 'stack overflow' error,
- ** but without 'msg'.)
- */
- LUALIB_API void luaL_checkstack (lua_State *L, int space, const char *msg) {
- if (!lua_checkstack(L, space)) {
- if (msg)
- luaL_error(L, "stack overflow (%s)", msg);
- else
- luaL_error(L, "stack overflow");
- }
- }
- LUALIB_API void luaL_checktype (lua_State *L, int arg, int t) {
- if (lua_type(L, arg) != t)
- tag_error(L, arg, t);
- }
- LUALIB_API void luaL_checkany (lua_State *L, int arg) {
- if (lua_type(L, arg) == LUA_TNONE)
- luaL_argerror(L, arg, "value expected");
- }
- LUALIB_API const char *luaL_checklstring (lua_State *L, int arg, size_t *len) {
- const char *s = lua_tolstring(L, arg, len);
- if (!s) tag_error(L, arg, LUA_TSTRING);
- return s;
- }
- LUALIB_API const char *luaL_optlstring (lua_State *L, int arg,
- const char *def, size_t *len) {
- if (lua_isnoneornil(L, arg)) {
- if (len)
- *len = (def ? strlen(def) : 0);
- return def;
- }
- else return luaL_checklstring(L, arg, len);
- }
- LUALIB_API lua_Number luaL_checknumber (lua_State *L, int arg) {
- int isnum;
- lua_Number d = lua_tonumberx(L, arg, &isnum);
- if (!isnum)
- tag_error(L, arg, LUA_TNUMBER);
- return d;
- }
- LUALIB_API lua_Number luaL_optnumber (lua_State *L, int arg, lua_Number def) {
- return luaL_opt(L, luaL_checknumber, arg, def);
- }
- static void interror (lua_State *L, int arg) {
- if (lua_isnumber(L, arg))
- luaL_argerror(L, arg, "number has no integer representation");
- else
- tag_error(L, arg, LUA_TNUMBER);
- }
- LUALIB_API lua_Integer luaL_checkinteger (lua_State *L, int arg) {
- int isnum;
- lua_Integer d = lua_tointegerx(L, arg, &isnum);
- if (!isnum) {
- interror(L, arg);
- }
- return d;
- }
- LUALIB_API lua_Integer luaL_optinteger (lua_State *L, int arg,
- lua_Integer def) {
- return luaL_opt(L, luaL_checkinteger, arg, def);
- }
- /* }====================================================== */
- /*
- ** {======================================================
- ** Generic Buffer manipulation
- ** =======================================================
- */
- /* userdata to box arbitrary data */
- typedef struct UBox {
- void *box;
- size_t bsize;
- } UBox;
- static void *resizebox (lua_State *L, int idx, size_t newsize) {
- void *ud;
- lua_Alloc allocf = lua_getallocf(L, &ud);
- UBox *box = (UBox *)lua_touserdata(L, idx);
- void *temp = allocf(ud, box->box, box->bsize, newsize);
- if (temp == NULL && newsize > 0) { /* allocation error? */
- lua_pushliteral(L, "not enough memory");
- lua_error(L); /* raise a memory error */
- }
- box->box = temp;
- box->bsize = newsize;
- return temp;
- }
- static int boxgc (lua_State *L) {
- resizebox(L, 1, 0);
- return 0;
- }
- static const luaL_Reg boxmt[] = { /* box metamethods */
- {"__gc", boxgc},
- {"__close", boxgc},
- {NULL, NULL}
- };
- static void newbox (lua_State *L) {
- UBox *box = (UBox *)lua_newuserdatauv(L, sizeof(UBox), 0);
- box->box = NULL;
- box->bsize = 0;
- if (luaL_newmetatable(L, "_UBOX*")) /* creating metatable? */
- luaL_setfuncs(L, boxmt, 0); /* set its metamethods */
- lua_setmetatable(L, -2);
- }
- /*
- ** check whether buffer is using a userdata on the stack as a temporary
- ** buffer
- */
- #define buffonstack(B) ((B)->b != (B)->init.b)
- /*
- ** Compute new size for buffer 'B', enough to accommodate extra 'sz'
- ** bytes.
- */
- static size_t newbuffsize (luaL_Buffer *B, size_t sz) {
- size_t newsize = B->size * 2; /* double buffer size */
- if (MAX_SIZET - sz < B->n) /* overflow in (B->n + sz)? */
- return luaL_error(B->L, "buffer too large");
- if (newsize < B->n + sz) /* double is not big enough? */
- newsize = B->n + sz;
- return newsize;
- }
- /*
- ** Returns a pointer to a free area with at least 'sz' bytes in buffer
- ** 'B'. 'boxidx' is the relative position in the stack where the
- ** buffer's box is or should be.
- */
- static char *prepbuffsize (luaL_Buffer *B, size_t sz, int boxidx) {
- if (B->size - B->n >= sz) /* enough space? */
- return B->b + B->n;
- else {
- lua_State *L = B->L;
- char *newbuff;
- size_t newsize = newbuffsize(B, sz);
- /* create larger buffer */
- if (buffonstack(B)) /* buffer already has a box? */
- newbuff = (char *)resizebox(L, boxidx, newsize); /* resize it */
- else { /* no box yet */
- lua_pushnil(L); /* reserve slot for final result */
- newbox(L); /* create a new box */
- /* move box (and slot) to its intended position */
- lua_rotate(L, boxidx - 1, 2);
- lua_toclose(L, boxidx);
- newbuff = (char *)resizebox(L, boxidx, newsize);
- memcpy(newbuff, B->b, B->n * sizeof(char)); /* copy original content */
- }
- B->b = newbuff;
- B->size = newsize;
- return newbuff + B->n;
- }
- }
- /*
- ** returns a pointer to a free area with at least 'sz' bytes
- */
- LUALIB_API char *luaL_prepbuffsize (luaL_Buffer *B, size_t sz) {
- return prepbuffsize(B, sz, -1);
- }
- LUALIB_API void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l) {
- if (l > 0) { /* avoid 'memcpy' when 's' can be NULL */
- char *b = prepbuffsize(B, l, -1);
- memcpy(b, s, l * sizeof(char));
- luaL_addsize(B, l);
- }
- }
- 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) {
- lua_State *L = B->L;
- lua_pushlstring(L, B->b, B->n);
- if (buffonstack(B)) {
- lua_copy(L, -1, -3); /* move string to reserved slot */
- lua_pop(L, 2); /* pop string and box (closing the box) */
- }
- }
- LUALIB_API void luaL_pushresultsize (luaL_Buffer *B, size_t sz) {
- luaL_addsize(B, sz);
- luaL_pushresult(B);
- }
- /*
- ** 'luaL_addvalue' is the only function in the Buffer system where the
- ** box (if existent) is not on the top of the stack. So, instead of
- ** calling 'luaL_addlstring', it replicates the code using -2 as the
- ** last argument to 'prepbuffsize', signaling that the box is (or will
- ** be) bellow the string being added to the buffer. (Box creation can
- ** trigger an emergency GC, so we should not remove the string from the
- ** stack before we have the space guaranteed.)
- */
- LUALIB_API void luaL_addvalue (luaL_Buffer *B) {
- lua_State *L = B->L;
- size_t len;
- const char *s = lua_tolstring(L, -1, &len);
- char *b = prepbuffsize(B, len, -2);
- memcpy(b, s, len * sizeof(char));
- luaL_addsize(B, len);
- lua_pop(L, 1); /* pop string */
- }
- LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) {
- B->L = L;
- B->b = B->init.b;
- B->n = 0;
- B->size = LUAL_BUFFERSIZE;
- }
- LUALIB_API char *luaL_buffinitsize (lua_State *L, luaL_Buffer *B, size_t sz) {
- luaL_buffinit(L, B);
- return prepbuffsize(B, sz, -1);
- }
- /* }====================================================== */
- /*
- ** {======================================================
- ** Reference system
- ** =======================================================
- */
- /* index of free-list header */
- #define freelist 0
- LUALIB_API int luaL_ref (lua_State *L, int t) {
- int ref;
- if (lua_isnil(L, -1)) {
- lua_pop(L, 1); /* remove from stack */
- return LUA_REFNIL; /* 'nil' has a unique fixed reference */
- }
- t = lua_absindex(L, t);
- lua_rawgeti(L, t, freelist); /* get first free element */
- ref = (int)lua_tointeger(L, -1); /* ref = t[freelist] */
- 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); /* (t[freelist] = t[ref]) */
- }
- else /* no free elements */
- ref = (int)lua_rawlen(L, t) + 1; /* get a 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 = lua_absindex(L, t);
- lua_rawgeti(L, t, freelist);
- lua_rawseti(L, t, ref); /* t[ref] = t[freelist] */
- lua_pushinteger(L, ref);
- lua_rawseti(L, t, freelist); /* t[freelist] = ref */
- }
- }
- /* }====================================================== */
- /*
- ** {======================================================
- ** Load functions
- ** =======================================================
- */
- typedef struct LoadF {
- int n; /* number of pre-read characters */
- FILE *f; /* file being read */
- char buff[BUFSIZ]; /* area for reading file */
- } LoadF;
- static const char *getF (lua_State *L, void *ud, size_t *size) {
- LoadF *lf = (LoadF *)ud;
- (void)L; /* not used */
- if (lf->n > 0) { /* are there pre-read characters to be read? */
- *size = lf->n; /* return them (chars already in buffer) */
- lf->n = 0; /* no more pre-read characters */
- }
- else { /* read a block from file */
- /* 'fread' can return > 0 *and* set the EOF flag. If next call to
- 'getF' called 'fread', it might still wait for user input.
- The next check avoids this problem. */
- if (feof(lf->f)) return NULL;
- *size = fread(lf->buff, 1, sizeof(lf->buff), lf->f); /* read block */
- }
- return lf->buff;
- }
- 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;
- }
- static int skipBOM (LoadF *lf) {
- const char *p = "\xEF\xBB\xBF"; /* UTF-8 BOM mark */
- int c;
- lf->n = 0;
- do {
- c = getc(lf->f);
- if (c == EOF || c != *(const unsigned char *)p++) return c;
- lf->buff[lf->n++] = c; /* to be read by the parser */
- } while (*p != '\0');
- lf->n = 0; /* prefix matched; discard it */
- return getc(lf->f); /* return next character */
- }
- /*
- ** reads the first character of file 'f' and skips an optional BOM mark
- ** in its beginning plus its first line if it starts with '#'. Returns
- ** true if it skipped the first line. In any case, '*cp' has the
- ** first "valid" character of the file (after the optional BOM and
- ** a first-line comment).
- */
- static int skipcomment (LoadF *lf, int *cp) {
- int c = *cp = skipBOM(lf);
- if (c == '#') { /* first line is a comment (Unix exec. file)? */
- do { /* skip first line */
- c = getc(lf->f);
- } while (c != EOF && c != '\n');
- *cp = getc(lf->f); /* skip end-of-line, if present */
- return 1; /* there was a comment */
- }
- else return 0; /* no comment */
- }
- LUALIB_API int luaL_loadfilex (lua_State *L, const char *filename,
- const char *mode) {
- LoadF lf;
- int status, readstatus;
- int c;
- int fnameindex = lua_gettop(L) + 1; /* index of filename on the stack */
- 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);
- }
- if (skipcomment(&lf, &c)) /* read initial portion */
- lf.buff[lf.n++] = '\n'; /* add line to correct line numbers */
- 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);
- skipcomment(&lf, &c); /* re-read initial portion */
- }
- if (c != EOF)
- lf.buff[lf.n++] = c; /* 'c' is the first character of the stream */
- status = lua_load(L, getF, &lf, lua_tostring(L, -1), mode);
- 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; /* not used */
- if (ls->size == 0) return NULL;
- *size = ls->size;
- ls->size = 0;
- return ls->s;
- }
- LUALIB_API int luaL_loadbufferx (lua_State *L, const char *buff, size_t size,
- const char *name, const char *mode) {
- LoadS ls;
- ls.s = buff;
- ls.size = size;
- return lua_load(L, getS, &ls, name, mode);
- }
- LUALIB_API int luaL_loadstring (lua_State *L, const char *s) {
- return luaL_loadbuffer(L, s, strlen(s), s);
- }
- /* }====================================================== */
- LUALIB_API int luaL_getmetafield (lua_State *L, int obj, const char *event) {
- if (!lua_getmetatable(L, obj)) /* no metatable? */
- return LUA_TNIL;
- else {
- int tt;
- lua_pushstring(L, event);
- tt = lua_rawget(L, -2);
- if (tt == LUA_TNIL) /* is metafield nil? */
- lua_pop(L, 2); /* remove metatable and metafield */
- else
- lua_remove(L, -2); /* remove only metatable */
- return tt; /* return metafield type */
- }
- }
- LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *event) {
- obj = lua_absindex(L, obj);
- if (luaL_getmetafield(L, obj, event) == LUA_TNIL) /* no metafield? */
- return 0;
- lua_pushvalue(L, obj);
- lua_call(L, 1, 1);
- return 1;
- }
- LUALIB_API lua_Integer luaL_len (lua_State *L, int idx) {
- lua_Integer l;
- int isnum;
- lua_len(L, idx);
- l = lua_tointegerx(L, -1, &isnum);
- if (!isnum)
- luaL_error(L, "object length is not an integer");
- lua_pop(L, 1); /* remove object */
- return l;
- }
- LUALIB_API const char *luaL_tolstring (lua_State *L, int idx, size_t *len) {
- if (luaL_callmeta(L, idx, "__tostring")) { /* metafield? */
- if (!lua_isstring(L, -1))
- luaL_error(L, "'__tostring' must return a string");
- }
- else {
- switch (lua_type(L, idx)) {
- case LUA_TNUMBER: {
- if (lua_isinteger(L, idx))
- lua_pushfstring(L, "%I", (LUAI_UACINT)lua_tointeger(L, idx));
- else
- lua_pushfstring(L, "%f", (LUAI_UACNUMBER)lua_tonumber(L, idx));
- break;
- }
- case LUA_TSTRING:
- lua_pushvalue(L, idx);
- break;
- case LUA_TBOOLEAN:
- lua_pushstring(L, (lua_toboolean(L, idx) ? "true" : "false"));
- break;
- case LUA_TNIL:
- lua_pushliteral(L, "nil");
- break;
- default: {
- int tt = luaL_getmetafield(L, idx, "__name"); /* try name */
- const char *kind = (tt == LUA_TSTRING) ? lua_tostring(L, -1) :
- luaL_typename(L, idx);
- lua_pushfstring(L, "%s: %p", kind, lua_topointer(L, idx));
- if (tt != LUA_TNIL)
- lua_remove(L, -2); /* remove '__name' */
- break;
- }
- }
- }
- return lua_tolstring(L, -1, len);
- }
- /*
- ** set functions from list 'l' into table at top - 'nup'; each
- ** function gets the 'nup' elements at the top as upvalues.
- ** Returns with only the table at the stack.
- */
- LUALIB_API void luaL_setfuncs (lua_State *L, const luaL_Reg *l, int nup) {
- luaL_checkstack(L, nup, "too many upvalues");
- for (; l->name != NULL; l++) { /* fill the table with given functions */
- if (l->func == NULL) /* place holder? */
- lua_pushboolean(L, 0);
- else {
- int i;
- for (i = 0; i < nup; i++) /* copy upvalues to the top */
- lua_pushvalue(L, -nup);
- lua_pushcclosure(L, l->func, nup); /* closure with those upvalues */
- }
- lua_setfield(L, -(nup + 2), l->name);
- }
- lua_pop(L, nup); /* remove upvalues */
- }
- /*
- ** ensure that stack[idx][fname] has a table and push that table
- ** into the stack
- */
- LUALIB_API int luaL_getsubtable (lua_State *L, int idx, const char *fname) {
- if (lua_getfield(L, idx, fname) == LUA_TTABLE)
- return 1; /* table already there */
- else {
- lua_pop(L, 1); /* remove previous result */
- idx = lua_absindex(L, idx);
- lua_newtable(L);
- lua_pushvalue(L, -1); /* copy to be left at top */
- lua_setfield(L, idx, fname); /* assign new table to field */
- return 0; /* false, because did not find table there */
- }
- }
- /*
- ** Stripped-down 'require': After checking "loaded" table, calls 'openf'
- ** to open a module, registers the result in 'package.loaded' table and,
- ** if 'glb' is true, also registers the result in the global table.
- ** Leaves resulting module on the top.
- */
- LUALIB_API void luaL_requiref (lua_State *L, const char *modname,
- lua_CFunction openf, int glb) {
- luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE);
- lua_getfield(L, -1, modname); /* LOADED[modname] */
- if (!lua_toboolean(L, -1)) { /* package not already loaded? */
- lua_pop(L, 1); /* remove field */
- lua_pushcfunction(L, openf);
- lua_pushstring(L, modname); /* argument to open function */
- lua_call(L, 1, 1); /* call 'openf' to open module */
- lua_pushvalue(L, -1); /* make copy of module (call result) */
- lua_setfield(L, -3, modname); /* LOADED[modname] = module */
- }
- lua_remove(L, -2); /* remove LOADED table */
- if (glb) {
- lua_pushvalue(L, -1); /* copy of module */
- lua_setglobal(L, modname); /* _G[modname] = module */
- }
- }
- LUALIB_API void luaL_addgsub (luaL_Buffer *b, const char *s,
- const char *p, const char *r) {
- const char *wild;
- size_t l = strlen(p);
- 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 */
- }
- LUALIB_API const char *luaL_gsub (lua_State *L, const char *s,
- const char *p, const char *r) {
- luaL_Buffer b;
- luaL_buffinit(L, &b);
- luaL_addgsub(&b, s, p, r);
- luaL_pushresult(&b);
- return lua_tostring(L, -1);
- }
- static void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize) {
- (void)ud; (void)osize; /* not used */
- if (nsize == 0) {
- free(ptr);
- return NULL;
- }
- else
- return realloc(ptr, nsize);
- }
- static int panic (lua_State *L) {
- const char *msg = lua_tostring(L, -1);
- if (msg == NULL) msg = "error object is not a string";
- lua_writestringerror("PANIC: unprotected error in call to Lua API (%s)\n",
- msg);
- return 0; /* return to Lua to abort */
- }
- /*
- ** Warning functions:
- ** warnfoff: warning system is off
- ** warnfon: ready to start a new message
- ** warnfcont: previous message is to be continued
- */
- static void warnfoff (void *ud, const char *message, int tocont);
- static void warnfon (void *ud, const char *message, int tocont);
- static void warnfcont (void *ud, const char *message, int tocont);
- /*
- ** Check whether message is a control message. If so, execute the
- ** control or ignore it if unknown.
- */
- static int checkcontrol (lua_State *L, const char *message, int tocont) {
- if (tocont || *(message++) != '@') /* not a control message? */
- return 0;
- else {
- if (strcmp(message, "off") == 0)
- lua_setwarnf(L, warnfoff, L); /* turn warnings off */
- else if (strcmp(message, "on") == 0)
- lua_setwarnf(L, warnfon, L); /* turn warnings on */
- return 1; /* it was a control message */
- }
- }
- static void warnfoff (void *ud, const char *message, int tocont) {
- checkcontrol((lua_State *)ud, message, tocont);
- }
- /*
- ** Writes the message and handle 'tocont', finishing the message
- ** if needed and setting the next warn function.
- */
- static void warnfcont (void *ud, const char *message, int tocont) {
- lua_State *L = (lua_State *)ud;
- lua_writestringerror("%s", message); /* write message */
- if (tocont) /* not the last part? */
- lua_setwarnf(L, warnfcont, L); /* to be continued */
- else { /* last part */
- lua_writestringerror("%s", "\n"); /* finish message with end-of-line */
- lua_setwarnf(L, warnfon, L); /* next call is a new message */
- }
- }
- static void warnfon (void *ud, const char *message, int tocont) {
- if (checkcontrol((lua_State *)ud, message, tocont)) /* control message? */
- return; /* nothing else to be done */
- lua_writestringerror("%s", "Lua warning: "); /* start a new warning */
- warnfcont(ud, message, tocont); /* finish processing */
- }
- LUALIB_API lua_State *luaL_newstate (void) {
- lua_State *L = lua_newstate(l_alloc, NULL);
- if (L) {
- lua_atpanic(L, &panic);
- lua_setwarnf(L, warnfoff, L); /* default is warnings off */
- }
- return L;
- }
- LUALIB_API void luaL_checkversion_ (lua_State *L, lua_Number ver, size_t sz) {
- lua_Number v = lua_version(L);
- if (sz != LUAL_NUMSIZES) /* check numeric types */
- luaL_error(L, "core and library have incompatible numeric types");
- else if (v != ver)
- luaL_error(L, "version mismatch: app. needs %f, Lua core provides %f",
- (LUAI_UACNUMBER)ver, (LUAI_UACNUMBER)v);
- }
|