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Diffstat (limited to 'src/lauxlib.c')
| -rw-r--r-- | src/lauxlib.c | 1048 |
1 files changed, 1048 insertions, 0 deletions
diff --git a/src/lauxlib.c b/src/lauxlib.c new file mode 100644 index 0000000..ac68bd3 --- /dev/null +++ b/src/lauxlib.c @@ -0,0 +1,1048 @@ +/* +** $Id: lauxlib.c,v 1.289.1.1 2017/04/19 17:20:42 roberto Exp $ +** 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" + + +/* +** {====================================================== +** 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. +** return 1 + string at top if find 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 */ + lua_remove(L, -2); /* remove table (but keep name) */ + lua_pushliteral(L, "."); + lua_insert(L, -2); /* place '.' between the two names */ + lua_concat(L, 3); + 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, "_G.", 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); /* move name to proper place */ + lua_pop(L, 2); /* remove pushed values */ + 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) { + lua_Debug ar; + int top = lua_gettop(L); + int last = lastlevel(L1); + int n1 = (last - level > LEVELS1 + LEVELS2) ? LEVELS1 : -1; + if (msg) + lua_pushfstring(L, "%s\n", msg); + luaL_checkstack(L, 10, NULL); + lua_pushliteral(L, "stack traceback:"); + while (lua_getstack(L1, level++, &ar)) { + if (n1-- == 0) { /* too many levels? */ + lua_pushliteral(L, "\n\t..."); /* add a '...' */ + level = last - LEVELS2 + 1; /* and skip to last ones */ + } + else { + lua_getinfo(L1, "Slnt", &ar); + lua_pushfstring(L, "\n\t%s:", ar.short_src); + if (ar.currentline > 0) + lua_pushfstring(L, "%d:", ar.currentline); + lua_pushliteral(L, " in "); + pushfuncname(L, &ar); + if (ar.istailcall) + lua_pushliteral(L, "\n\t(...tail calls...)"); + lua_concat(L, lua_gettop(L) - top); + } + } + lua_concat(L, lua_gettop(L) - top); +} + +/* }====================================================== */ + + +/* +** {====================================================== +** 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); +} + + +static int 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) { + 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 { + lua_pushnil(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) { + const char *what = "exit"; /* type of termination */ + if (stat == -1) /* error? */ + return luaL_fileresult(L, 0, NULL); + else { + l_inspectstat(stat, what); /* interpret result */ + if (*what == 'e' && stat == 0) /* successful termination? */ + lua_pushboolean(L, 1); + else + lua_pushnil(L); + lua_pushstring(L, what); + lua_pushinteger(L, stat); + return 3; /* return true/nil,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); + if (p == NULL) typeerror(L, 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? */ + resizebox(L, idx, 0); /* free buffer */ + luaL_error(L, "not enough memory for buffer allocation"); + } + box->box = temp; + box->bsize = newsize; + return temp; +} + + +static int boxgc (lua_State *L) { + resizebox(L, 1, 0); + return 0; +} + + +static void *newbox (lua_State *L, size_t newsize) { + UBox *box = (UBox *)lua_newuserdata(L, sizeof(UBox)); + box->box = NULL; + box->bsize = 0; + if (luaL_newmetatable(L, "LUABOX")) { /* creating metatable? */ + lua_pushcfunction(L, boxgc); + lua_setfield(L, -2, "__gc"); /* metatable.__gc = boxgc */ + } + lua_setmetatable(L, -2); + return resizebox(L, -1, newsize); +} + + +/* +** check whether buffer is using a userdata on the stack as a temporary +** buffer +*/ +#define buffonstack(B) ((B)->b != (B)->initb) + + +/* +** returns a pointer to a free area with at least 'sz' bytes +*/ +LUALIB_API char *luaL_prepbuffsize (luaL_Buffer *B, size_t sz) { + lua_State *L = B->L; + if (B->size - B->n < sz) { /* not enough space? */ + char *newbuff; + size_t newsize = B->size * 2; /* double buffer size */ + if (newsize - B->n < sz) /* not big enough? */ + newsize = B->n + sz; + if (newsize < B->n || newsize - B->n < sz) + luaL_error(L, "buffer too large"); + /* create larger buffer */ + if (buffonstack(B)) + newbuff = (char *)resizebox(L, -1, newsize); + else { /* no buffer yet */ + newbuff = (char *)newbox(L, newsize); + memcpy(newbuff, B->b, B->n * sizeof(char)); /* copy original content */ + } + B->b = newbuff; + B->size = newsize; + } + return &B->b[B->n]; +} + + +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 = luaL_prepbuffsize(B, l); + 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)) { + resizebox(L, -2, 0); /* delete old buffer */ + lua_remove(L, -2); /* remove its header from the stack */ + } +} + + +LUALIB_API void luaL_pushresultsize (luaL_Buffer *B, size_t sz) { + luaL_addsize(B, sz); + luaL_pushresult(B); +} + + +LUALIB_API void luaL_addvalue (luaL_Buffer *B) { + lua_State *L = B->L; + size_t l; + const char *s = lua_tolstring(L, -1, &l); + if (buffonstack(B)) + lua_insert(L, -2); /* put value below buffer */ + luaL_addlstring(B, s, l); + lua_remove(L, (buffonstack(B)) ? -2 : -1); /* remove value */ +} + + +LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) { + B->L = L; + B->b = B->initb; + 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 luaL_prepbuffsize(B, sz); +} + +/* }====================================================== */ + + +/* +** {====================================================== +** 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); +} + + +/* +** {====================================================== +** Compatibility with 5.1 module functions +** ======================================================= +*/ +#if defined(LUA_COMPAT_MODULE) + +static const char *luaL_findtable (lua_State *L, int idx, + const char *fname, int szhint) { + const char *e; + if (idx) lua_pushvalue(L, idx); + do { + e = strchr(fname, '.'); + if (e == NULL) e = fname + strlen(fname); + lua_pushlstring(L, fname, e - fname); + if (lua_rawget(L, -2) == LUA_TNIL) { /* 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; +} + + +/* +** Count number of elements in a luaL_Reg list. +*/ +static int libsize (const luaL_Reg *l) { + int size = 0; + for (; l && l->name; l++) size++; + return size; +} + + +/* +** Find or create a module table with a given name. The function +** first looks at the LOADED table and, if that fails, try a +** global variable with that name. In any case, leaves on the stack +** the module table. +*/ +LUALIB_API void luaL_pushmodule (lua_State *L, const char *modname, + int sizehint) { + luaL_findtable(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE, 1); + if (lua_getfield(L, -1, modname) != LUA_TTABLE) { /* no LOADED[modname]? */ + lua_pop(L, 1); /* remove previous result */ + /* try global variable (and create one if it does not exist) */ + lua_pushglobaltable(L); + if (luaL_findtable(L, 0, modname, sizehint) != NULL) + luaL_error(L, "name conflict for module '%s'", modname); + lua_pushvalue(L, -1); + lua_setfield(L, -3, modname); /* LOADED[modname] = new table */ + } + lua_remove(L, -2); /* remove LOADED table */ +} + + +LUALIB_API void luaL_openlib (lua_State *L, const char *libname, + const luaL_Reg *l, int nup) { + luaL_checkversion(L); + if (libname) { + luaL_pushmodule(L, libname, libsize(l)); /* get/create library table */ + lua_insert(L, -(nup + 1)); /* move library table to below upvalues */ + } + if (l) + luaL_setfuncs(L, l, nup); + else + lua_pop(L, nup); /* remove upvalues */ +} + +#endif +/* }====================================================== */ + +/* +** 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 */ + 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 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); +} + + +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 { /* cannot fail when shrinking a block */ + void *newptr = realloc(ptr, nsize); + if (newptr == NULL && ptr != NULL && nsize <= osize) + return ptr; /* keep the original block */ + else /* no fail or not shrinking */ + return newptr; /* use the new block */ + } +} + + +static int panic (lua_State *L) { + lua_writestringerror("PANIC: unprotected error in call to Lua API (%s)\n", + lua_tostring(L, -1)); + return 0; /* return to Lua to abort */ +} + + +LUALIB_API lua_State *luaL_newstate (void) { + lua_State *L = lua_newstate(l_alloc, NULL); + if (L) lua_atpanic(L, &panic); + return L; +} + + +LUALIB_API void luaL_checkversion_ (lua_State *L, lua_Number ver, size_t sz) { + const lua_Number *v = lua_version(L); + if (sz != LUAL_NUMSIZES) /* check numeric types */ + luaL_error(L, "core and library have incompatible numeric types"); + if (v != lua_version(NULL)) + luaL_error(L, "multiple Lua VMs detected"); + else if (*v != ver) + luaL_error(L, "version mismatch: app. needs %f, Lua core provides %f", + (LUAI_UACNUMBER)ver, (LUAI_UACNUMBER)*v); +} + |