/* ** $Id: liolib.c,v 2.150 2016/09/01 16:14:56 roberto Exp roberto $ ** Standard I/O (and system) library ** See Copyright Notice in lua.h */ #define liolib_c #define LUA_LIB #include "lprefix.h" #include #include #include #include #include #include #include "lua.h" #include "lauxlib.h" #include "lualib.h" /* ** Change this macro to accept other modes for 'fopen' besides ** the standard ones. */ #if !defined(l_checkmode) /* accepted extensions to 'mode' in 'fopen' */ #if !defined(L_MODEEXT) #define L_MODEEXT "b" #endif /* Check whether 'mode' matches '[rwa]%+?[L_MODEEXT]*' */ static int l_checkmode (const char *mode) { return (*mode != '\0' && strchr("rwa", *(mode++)) != NULL && (*mode != '+' || (++mode, 1)) && /* skip if char is '+' */ (strspn(mode, L_MODEEXT) == strlen(mode))); /* check extensions */ } #endif /* ** {====================================================== ** l_popen spawns a new process connected to the current ** one through the file streams. ** ======================================================= */ #if !defined(l_popen) /* { */ #if defined(LUA_USE_POSIX) /* { */ #define l_popen(L,c,m) (fflush(NULL), popen(c,m)) #define l_pclose(L,file) (pclose(file)) #elif defined(LUA_USE_WINDOWS) /* }{ */ #define l_popen(L,c,m) (_popen(c,m)) #define l_pclose(L,file) (_pclose(file)) #else /* }{ */ /* ISO C definitions */ #define l_popen(L,c,m) \ ((void)((void)c, m), \ luaL_error(L, "'popen' not supported"), \ (FILE*)0) #define l_pclose(L,file) ((void)L, (void)file, -1) #endif /* } */ #endif /* } */ /* }====================================================== */ #if !defined(l_getc) /* { */ #if defined(LUA_USE_POSIX) #define l_getc(f) getc_unlocked(f) #define l_lockfile(f) flockfile(f) #define l_unlockfile(f) funlockfile(f) #else #define l_getc(f) getc(f) #define l_lockfile(f) ((void)0) #define l_unlockfile(f) ((void)0) #endif #endif /* } */ /* ** {====================================================== ** l_fseek: configuration for longer offsets ** ======================================================= */ #if !defined(l_fseek) /* { */ #if defined(LUA_USE_POSIX) /* { */ #include #define l_fseek(f,o,w) fseeko(f,o,w) #define l_ftell(f) ftello(f) #define l_seeknum off_t #elif defined(LUA_USE_WINDOWS) && !defined(_CRTIMP_TYPEINFO) \ && defined(_MSC_VER) && (_MSC_VER >= 1400) /* }{ */ /* Windows (but not DDK) and Visual C++ 2005 or higher */ #define l_fseek(f,o,w) _fseeki64(f,o,w) #define l_ftell(f) _ftelli64(f) #define l_seeknum __int64 #else /* }{ */ /* ISO C definitions */ #define l_fseek(f,o,w) fseek(f,o,w) #define l_ftell(f) ftell(f) #define l_seeknum long #endif /* } */ #endif /* } */ /* }====================================================== */ #define IO_PREFIX "_IO_" #define IOPREF_LEN (sizeof(IO_PREFIX)/sizeof(char) - 1) #define IO_INPUT (IO_PREFIX "input") #define IO_OUTPUT (IO_PREFIX "output") typedef luaL_Stream LStream; #define tolstream(L) ((LStream *)luaL_checkudata(L, 1, LUA_FILEHANDLE)) #define isclosed(p) ((p)->closef == NULL) static int io_type (lua_State *L) { LStream *p; luaL_checkany(L, 1); p = (LStream *)luaL_testudata(L, 1, LUA_FILEHANDLE); if (p == NULL) lua_pushnil(L); /* not a file */ else if (isclosed(p)) lua_pushliteral(L, "closed file"); else lua_pushliteral(L, "file"); return 1; } static int f_tostring (lua_State *L) { LStream *p = tolstream(L); if (isclosed(p)) lua_pushliteral(L, "file (closed)"); else lua_pushfstring(L, "file (%p)", p->f); return 1; } static FILE *tofile (lua_State *L) { LStream *p = tolstream(L); if (isclosed(p)) luaL_error(L, "attempt to use a closed file"); lua_assert(p->f); return p->f; } /* ** When creating file handles, always creates a 'closed' file handle ** before opening the actual file; so, if there is a memory error, the ** handle is in a consistent state. */ static LStream *newprefile (lua_State *L) { LStream *p = (LStream *)lua_newuserdata(L, sizeof(LStream)); p->closef = NULL; /* mark file handle as 'closed' */ luaL_setmetatable(L, LUA_FILEHANDLE); return p; } /* ** Calls the 'close' function from a file handle. The 'volatile' avoids ** a bug in some versions of the Clang compiler (e.g., clang 3.0 for ** 32 bits). */ static int aux_close (lua_State *L) { LStream *p = tolstream(L); volatile lua_CFunction cf = p->closef; p->closef = NULL; /* mark stream as closed */ return (*cf)(L); /* close it */ } static int io_close (lua_State *L) { if (lua_isnone(L, 1)) /* no argument? */ lua_getfield(L, LUA_REGISTRYINDEX, IO_OUTPUT); /* use standard output */ tofile(L); /* make sure argument is an open stream */ return aux_close(L); } static int f_gc (lua_State *L) { LStream *p = tolstream(L); if (!isclosed(p) && p->f != NULL) aux_close(L); /* ignore closed and incompletely open files */ return 0; } /* ** function to close regular files */ static int io_fclose (lua_State *L) { LStream *p = tolstream(L); int res = fclose(p->f); return luaL_fileresult(L, (res == 0), NULL); } static LStream *newfile (lua_State *L) { LStream *p = newprefile(L); p->f = NULL; p->closef = &io_fclose; return p; } static void opencheck (lua_State *L, const char *fname, const char *mode) { LStream *p = newfile(L); p->f = fopen(fname, mode); if (p->f == NULL) luaL_error(L, "cannot open file '%s' (%s)", fname, strerror(errno)); } static int io_open (lua_State *L) { const char *filename = luaL_checkstring(L, 1); const char *mode = luaL_optstring(L, 2, "r"); LStream *p = newfile(L); const char *md = mode; /* to traverse/check mode */ luaL_argcheck(L, l_checkmode(md), 2, "invalid mode"); p->f = fopen(filename, mode); return (p->f == NULL) ? luaL_fileresult(L, 0, filename) : 1; } /* ** function to close 'popen' files */ static int io_pclose (lua_State *L) { LStream *p = tolstream(L); return luaL_execresult(L, l_pclose(L, p->f)); } static int io_popen (lua_State *L) { const char *filename = luaL_checkstring(L, 1); const char *mode = luaL_optstring(L, 2, "r"); LStream *p = newprefile(L); p->f = l_popen(L, filename, mode); p->closef = &io_pclose; return (p->f == NULL) ? luaL_fileresult(L, 0, filename) : 1; } static int io_tmpfile (lua_State *L) { LStream *p = newfile(L); p->f = tmpfile(); return (p->f == NULL) ? luaL_fileresult(L, 0, NULL) : 1; } static FILE *getiofile (lua_State *L, const char *findex) { LStream *p; lua_getfield(L, LUA_REGISTRYINDEX, findex); p = (LStream *)lua_touserdata(L, -1); if (isclosed(p)) luaL_error(L, "standard %s file is closed", findex + IOPREF_LEN); return p->f; } static int g_iofile (lua_State *L, const char *f, const char *mode) { if (!lua_isnoneornil(L, 1)) { const char *filename = lua_tostring(L, 1); if (filename) opencheck(L, filename, mode); else { tofile(L); /* check that it's a valid file handle */ lua_pushvalue(L, 1); } lua_setfield(L, LUA_REGISTRYINDEX, f); } /* return current value */ lua_getfield(L, LUA_REGISTRYINDEX, f); return 1; } static int io_input (lua_State *L) { return g_iofile(L, IO_INPUT, "r"); } static int io_output (lua_State *L) { return g_iofile(L, IO_OUTPUT, "w"); } static int io_readline (lua_State *L); /* ** maximum number of arguments to 'f:lines'/'io.lines' (it + 3 must fit ** in the limit for upvalues of a closure) */ #define MAXARGLINE 250 static void aux_lines (lua_State *L, int toclose) { int n = lua_gettop(L) - 1; /* number of arguments to read */ luaL_argcheck(L, n <= MAXARGLINE, MAXARGLINE + 2, "too many arguments"); lua_pushinteger(L, n); /* number of arguments to read */ lua_pushboolean(L, toclose); /* close/not close file when finished */ lua_rotate(L, 2, 2); /* move 'n' and 'toclose' to their positions */ lua_pushcclosure(L, io_readline, 3 + n); } static int f_lines (lua_State *L) { tofile(L); /* check that it's a valid file handle */ aux_lines(L, 0); return 1; } static int io_lines (lua_State *L) { int toclose; if (lua_isnone(L, 1)) lua_pushnil(L); /* at least one argument */ if (lua_isnil(L, 1)) { /* no file name? */ lua_getfield(L, LUA_REGISTRYINDEX, IO_INPUT); /* get default input */ lua_replace(L, 1); /* put it at index 1 */ tofile(L); /* check that it's a valid file handle */ toclose = 0; /* do not close it after iteration */ } else { /* open a new file */ const char *filename = luaL_checkstring(L, 1); opencheck(L, filename, "r"); lua_replace(L, 1); /* put file at index 1 */ toclose = 1; /* close it after iteration */ } aux_lines(L, toclose); return 1; } /* ** {====================================================== ** READ ** ======================================================= */ /* maximum length of a numeral */ #if !defined (L_MAXLENNUM) #define L_MAXLENNUM 200 #endif /* auxiliary structure used by 'read_number' */ typedef struct { FILE *f; /* file being read */ int c; /* current character (look ahead) */ int n; /* number of elements in buffer 'buff' */ char buff[L_MAXLENNUM + 1]; /* +1 for ending '\0' */ } RN; /* ** Add current char to buffer (if not out of space) and read next one */ static int nextc (RN *rn) { if (rn->n >= L_MAXLENNUM) { /* buffer overflow? */ rn->buff[0] = '\0'; /* invalidate result */ return 0; /* fail */ } else { rn->buff[rn->n++] = rn->c; /* save current char */ rn->c = l_getc(rn->f); /* read next one */ return 1; } } /* ** Accept current char if it is in 'set' (of size 2) */ static int test2 (RN *rn, const char *set) { if (rn->c == set[0] || rn->c == set[1]) return nextc(rn); else return 0; } /* ** Read a sequence of (hex)digits */ static int readdigits (RN *rn, int hex) { int count = 0; while ((hex ? isxdigit(rn->c) : isdigit(rn->c)) && nextc(rn)) count++; return count; } /* ** Read a number: first reads a valid prefix of a numeral into a buffer. ** Then it calls 'lua_stringtonumber' to check whether the format is ** correct and to convert it to a Lua number */ static int read_number (lua_State *L, FILE *f) { RN rn; int count = 0; int hex = 0; char decp[2]; rn.f = f; rn.n = 0; decp[0] = lua_getlocaledecpoint(); /* get decimal point from locale */ decp[1] = '.'; /* always accept a dot */ l_lockfile(rn.f); do { rn.c = l_getc(rn.f); } while (isspace(rn.c)); /* skip spaces */ test2(&rn, "-+"); /* optional signal */ if (test2(&rn, "00")) { if (test2(&rn, "xX")) hex = 1; /* numeral is hexadecimal */ else count = 1; /* count initial '0' as a valid digit */ } count += readdigits(&rn, hex); /* integral part */ if (test2(&rn, decp)) /* decimal point? */ count += readdigits(&rn, hex); /* fractional part */ if (count > 0 && test2(&rn, (hex ? "pP" : "eE"))) { /* exponent mark? */ test2(&rn, "-+"); /* exponent signal */ readdigits(&rn, 0); /* exponent digits */ } ungetc(rn.c, rn.f); /* unread look-ahead char */ l_unlockfile(rn.f); rn.buff[rn.n] = '\0'; /* finish string */ if (lua_stringtonumber(L, rn.buff)) /* is this a valid number? */ return 1; /* ok */ else { /* invalid format */ lua_pushnil(L); /* "result" to be removed */ return 0; /* read fails */ } } static int test_eof (lua_State *L, FILE *f) { int c = getc(f); ungetc(c, f); /* no-op when c == EOF */ lua_pushliteral(L, ""); return (c != EOF); } static int read_line (lua_State *L, FILE *f, int chop) { luaL_Buffer b; int c = '\0'; luaL_buffinit(L, &b); while (c != EOF && c != '\n') { /* repeat until end of line */ char *buff = luaL_prepbuffer(&b); /* preallocate buffer */ int i = 0; l_lockfile(f); /* no memory errors can happen inside the lock */ while (i < LUAL_BUFFERSIZE && (c = l_getc(f)) != EOF && c != '\n') buff[i++] = c; l_unlockfile(f); luaL_addsize(&b, i); } if (!chop && c == '\n') /* want a newline and have one? */ luaL_addchar(&b, c); /* add ending newline to result */ luaL_pushresult(&b); /* close buffer */ /* return ok if read something (either a newline or something else) */ return (c == '\n' || lua_rawlen(L, -1) > 0); } static void read_all (lua_State *L, FILE *f) { size_t nr; luaL_Buffer b; luaL_buffinit(L, &b); do { /* read file in chunks of LUAL_BUFFERSIZE bytes */ char *p = luaL_prepbuffer(&b); nr = fread(p, sizeof(char), LUAL_BUFFERSIZE, f); luaL_addsize(&b, nr); } while (nr == LUAL_BUFFERSIZE); luaL_pushresult(&b); /* close buffer */ } static int read_chars (lua_State *L, FILE *f, size_t n) { size_t nr; /* number of chars actually read */ char *p; luaL_Buffer b; luaL_buffinit(L, &b); p = luaL_prepbuffsize(&b, n); /* prepare buffer to read whole block */ nr = fread(p, sizeof(char), n, f); /* try to read 'n' chars */ luaL_addsize(&b, nr); luaL_pushresult(&b); /* close buffer */ return (nr > 0); /* true iff read something */ } static int g_read (lua_State *L, FILE *f, int first) { int nargs = lua_gettop(L) - 1; int success; int n; clearerr(f); if (nargs == 0) { /* no arguments? */ success = read_line(L, f, 1); n = first+1; /* to return 1 result */ } else { /* ensure stack space for all results and for auxlib's buffer */ luaL_checkstack(L, nargs+LUA_MINSTACK, "too many arguments"); success = 1; for (n = first; nargs-- && success; n++) { if (lua_type(L, n) == LUA_TNUMBER) { size_t l = (size_t)luaL_checkinteger(L, n); success = (l == 0) ? test_eof(L, f) : read_chars(L, f, l); } else { const char *p = luaL_checkstring(L, n); if (*p == '*') p++; /* skip optional '*' (for compatibility) */ switch (*p) { case 'n': /* number */ success = read_number(L, f); break; case 'l': /* line */ success = read_line(L, f, 1); break; case 'L': /* line with end-of-line */ success = read_line(L, f, 0); break; case 'a': /* file */ read_all(L, f); /* read entire file */ success = 1; /* always success */ break; default: return luaL_argerror(L, n, "invalid format"); } } } } if (ferror(f)) return luaL_fileresult(L, 0, NULL); if (!success) { lua_pop(L, 1); /* remove last result */ lua_pushnil(L); /* push nil instead */ } return n - first; } static int io_read (lua_State *L) { return g_read(L, getiofile(L, IO_INPUT), 1); } static int f_read (lua_State *L) { return g_read(L, tofile(L), 2); } static int io_readline (lua_State *L) { LStream *p = (LStream *)lua_touserdata(L, lua_upvalueindex(1)); int i; int n = (int)lua_tointeger(L, lua_upvalueindex(2)); if (isclosed(p)) /* file is already closed? */ return luaL_error(L, "file is already closed"); lua_settop(L , 1); luaL_checkstack(L, n, "too many arguments"); for (i = 1; i <= n; i++) /* push arguments to 'g_read' */ lua_pushvalue(L, lua_upvalueindex(3 + i)); n = g_read(L, p->f, 2); /* 'n' is number of results */ lua_assert(n > 0); /* should return at least a nil */ if (lua_toboolean(L, -n)) /* read at least one value? */ return n; /* return them */ else { /* first result is nil: EOF or error */ if (n > 1) { /* is there error information? */ /* 2nd result is error message */ return luaL_error(L, "%s", lua_tostring(L, -n + 1)); } if (lua_toboolean(L, lua_upvalueindex(3))) { /* generator created file? */ lua_settop(L, 0); lua_pushvalue(L, lua_upvalueindex(1)); aux_close(L); /* close it */ } return 0; } } /* }====================================================== */ static int g_write (lua_State *L, FILE *f, int arg) { int nargs = lua_gettop(L) - arg; int status = 1; for (; nargs--; arg++) { if (lua_type(L, arg) == LUA_TNUMBER) { /* optimization: could be done exactly as for strings */ int len = lua_isinteger(L, arg) ? fprintf(f, LUA_INTEGER_FMT, (LUAI_UACINT)lua_tointeger(L, arg)) : fprintf(f, LUA_NUMBER_FMT, (LUAI_UACNUMBER)lua_tonumber(L, arg)); status = status && (len > 0); } else { size_t l; const char *s = luaL_checklstring(L, arg, &l); status = status && (fwrite(s, sizeof(char), l, f) == l); } } if (status) return 1; /* file handle already on stack top */ else return luaL_fileresult(L, status, NULL); } static int io_write (lua_State *L) { return g_write(L, getiofile(L, IO_OUTPUT), 1); } static int f_write (lua_State *L) { FILE *f = tofile(L); lua_pushvalue(L, 1); /* push file at the stack top (to be returned) */ return g_write(L, f, 2); } static int f_seek (lua_State *L) { static const int mode[] = {SEEK_SET, SEEK_CUR, SEEK_END}; static const char *const modenames[] = {"set", "cur", "end", NULL}; FILE *f = tofile(L); int op = luaL_checkoption(L, 2, "cur", modenames); lua_Integer p3 = luaL_optinteger(L, 3, 0); l_seeknum offset = (l_seeknum)p3; luaL_argcheck(L, (lua_Integer)offset == p3, 3, "not an integer in proper range"); op = l_fseek(f, offset, mode[op]); if (op) return luaL_fileresult(L, 0, NULL); /* error */ else { lua_pushinteger(L, (lua_Integer)l_ftell(f)); return 1; } } static int f_setvbuf (lua_State *L) { static const int mode[] = {_IONBF, _IOFBF, _IOLBF}; static const char *const modenames[] = {"no", "full", "line", NULL}; FILE *f = tofile(L); int op = luaL_checkoption(L, 2, NULL, modenames); lua_Integer sz = luaL_optinteger(L, 3, LUAL_BUFFERSIZE); int res = setvbuf(f, NULL, mode[op], (size_t)sz); return luaL_fileresult(L, res == 0, NULL); } static int io_flush (lua_State *L) { return luaL_fileresult(L, fflush(getiofile(L, IO_OUTPUT)) == 0, NULL); } static int f_flush (lua_State *L) { return luaL_fileresult(L, fflush(tofile(L)) == 0, NULL); } /* ** functions for 'io' library */ static const luaL_Reg iolib[] = { {"close", io_close}, {"flush", io_flush}, {"input", io_input}, {"lines", io_lines}, {"open", io_open}, {"output", io_output}, {"popen", io_popen}, {"read", io_read}, {"tmpfile", io_tmpfile}, {"type", io_type}, {"write", io_write}, {NULL, NULL} }; /* ** methods for file handles */ static const luaL_Reg flib[] = { {"close", io_close}, {"flush", f_flush}, {"lines", f_lines}, {"read", f_read}, {"seek", f_seek}, {"setvbuf", f_setvbuf}, {"write", f_write}, {"__gc", f_gc}, {"__tostring", f_tostring}, {NULL, NULL} }; static void createmeta (lua_State *L) { luaL_newmetatable(L, LUA_FILEHANDLE); /* create metatable for file handles */ lua_pushvalue(L, -1); /* push metatable */ lua_setfield(L, -2, "__index"); /* metatable.__index = metatable */ luaL_setfuncs(L, flib, 0); /* add file methods to new metatable */ lua_pop(L, 1); /* pop new metatable */ } /* ** function to (not) close the standard files stdin, stdout, and stderr */ static int io_noclose (lua_State *L) { LStream *p = tolstream(L); p->closef = &io_noclose; /* keep file opened */ lua_pushnil(L); lua_pushliteral(L, "cannot close standard file"); return 2; } static void createstdfile (lua_State *L, FILE *f, const char *k, const char *fname) { LStream *p = newprefile(L); p->f = f; p->closef = &io_noclose; if (k != NULL) { lua_pushvalue(L, -1); lua_setfield(L, LUA_REGISTRYINDEX, k); /* add file to registry */ } lua_setfield(L, -2, fname); /* add file to module */ } LUAMOD_API int luaopen_io (lua_State *L) { luaL_newlib(L, iolib); /* new module */ createmeta(L); /* create (and set) default files */ createstdfile(L, stdin, IO_INPUT, "stdin"); createstdfile(L, stdout, IO_OUTPUT, "stdout"); createstdfile(L, stderr, NULL, "stderr"); return 1; }