lua55c/src/liolib.c at main · 2MoonsLua/lua55c · GitHub

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** $Id: liolib.c $

** Standard I/O (and system) library

** See Copyright Notice in lua.h

#define liolib_c

#define LUA_LIB

#include "lprefix.h"

#include <ctype.h>

#include <errno.h>

#include <locale.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include "lua.h"

#include "lauxlib.h"

#include "lualib.h"

#include "llimits.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 != '+' || ((void)(++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))

#if !defined(l_checkmodep)

/* Windows accepts "[rw][bt]?" as valid modes */

#define l_checkmodep(m) ((m[0] == 'r' || m[0] == 'w') && \

(m[1] == '\0' || ((m[1] == 'b' || m[1] == 't') && m[2] == '\0')))

#endif

#else /* }{ */

/* ISO C definitions */

#define l_popen(L,c,m) \

((void)c, (void)m, \

luaL_error(L, "'popen' not supported"), \

(FILE*)0)

#define l_pclose(L,file) ((void)L, (void)file, -1)

#endif /* } */

#if !defined(l_checkmodep)

/* By default, Lua accepts only "r" or "w" as valid modes */

#define l_checkmodep(m) ((m[0] == 'r' || m[0] == 'w') && m[1] == '\0')

#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) || defined(LUA_USE_OFF_T) /* { */

#include <sys/types.h>

#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 /* } */

/* }====================================================== */

#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)

luaL_pushfail(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 (l_unlikely(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_newuserdatauv(L, sizeof(LStream), 0);

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 f_close (lua_State *L) {

tofile(L); /* make sure argument is an open stream */

return aux_close(L);

}

static int io_close (lua_State *L) {

if (lua_isnone(L, 1)) /* no argument? */

lua_getfield(L, LUA_REGISTRYINDEX, IO_OUTPUT); /* use default output */

return f_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);

errno = 0;

return luaL_fileresult(L, (fclose(p->f) == 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 (l_unlikely(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");

errno = 0;

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);

errno = 0;

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);

luaL_argcheck(L, l_checkmodep(mode), 2, "invalid mode");

errno = 0;

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);

errno = 0;

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 (l_unlikely(isclosed(p)))

luaL_error(L, "default %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

** Auxiliary function to create the iteration function for 'lines'.

** The iteration function is a closure over 'io_readline', with

** the following upvalues:

** 1) The file being read (first value in the stack)

** 2) the number of arguments to read

** 3) a boolean, true iff file has to be closed when finished ('toclose')

** *) a variable number of format arguments (rest of the stack)

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_pushvalue(L, 1); /* file */

lua_pushinteger(L, n); /* number of arguments to read */

lua_pushboolean(L, toclose); /* close/not close file when finished */

lua_rotate(L, 2, 3); /* move the three values 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;

}

** Return an iteration function for 'io.lines'. If file has to be

** closed, also returns the file itself as a second result (to be

** closed as the state at the exit of a generic for).

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); /* push iteration function */

if (toclose) {

lua_pushnil(L); /* state */

lua_pushnil(L); /* control */

lua_pushvalue(L, 1); /* file is the to-be-closed variable (4th result) */

return 4;

}

else

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 (l_unlikely(rn->n >= L_MAXLENNUM)) { /* buffer overflow? */

rn->buff[0] = '\0'; /* invalidate result */

return 0; /* fail */

}

else {

rn->buff[rn->n++] = cast_char(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 sign */

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 sign */

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 (l_likely(lua_stringtonumber(L, rn.buff)))

return 1; /* ok, it is a valid number */

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;

luaL_buffinit(L, &b);

do { /* may need to read several chunks to get whole line */

char *buff = luaL_prepbuffer(&b); /* preallocate buffer space */

unsigned 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++] = cast_char(c); /* read up to end of line or buffer limit */

l_unlockfile(f);

luaL_addsize(&b, i);

} while (c != EOF && c != '\n'); /* repeat until end of line */

if (!chop && c == '\n') /* want a newline and have one? */

luaL_addchar(&b, '\n'); /* 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 n, success;

clearerr(f);

errno = 0;

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 */

luaL_pushfail(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);

}

** Iteration function for 'lines'.

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 false: 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); /* clear stack */

lua_pushvalue(L, lua_upvalueindex(1)); /* push file at index 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;

size_t totalbytes = 0; /* total number of bytes written */

errno = 0;

for (; nargs--; arg++) { /* for each argument */

char buff[LUA_N2SBUFFSZ];

const char *s;

size_t numbytes; /* bytes written in one call to 'fwrite' */

size_t len = lua_numbertocstring(L, arg, buff); /* try as a number */

if (len > 0) { /* did conversion work (value was a number)? */

s = buff;

len--;

}

else /* must be a string */

s = luaL_checklstring(L, arg, &len);

numbytes = fwrite(s, sizeof(char), len, f);

totalbytes += numbytes;

if (numbytes < len) { /* write error? */

int n = luaL_fileresult(L, 0, NULL);

lua_pushinteger(L, cast_st2S(totalbytes));

return n + 1; /* return fail, error msg., error code, and counter */

}

return 1; /* no errors; file handle already on stack top */

}

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");

errno = 0;

op = l_fseek(f, offset, mode[op]);

if (l_unlikely(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;

errno = 0;

res = setvbuf(f, NULL, mode[op], (size_t)sz);

return luaL_fileresult(L, res == 0, NULL);

}

static int aux_flush (lua_State *L, FILE *f) {

errno = 0;

return luaL_fileresult(L, fflush(f) == 0, NULL);

}

static int f_flush (lua_State *L) {

return aux_flush(L, tofile(L));

}

static int io_flush (lua_State *L) {

return aux_flush(L, getiofile(L, IO_OUTPUT));

}

** 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 meth[] = {

{"read", f_read},

{"write", f_write},

{"lines", f_lines},

{"flush", f_flush},

{"seek", f_seek},

{"close", f_close},

{"setvbuf", f_setvbuf},

{NULL, NULL}

};

** metamethods for file handles

static const luaL_Reg metameth[] = {

{"__index", NULL}, /* placeholder */

{"__gc", f_gc},

{"__close", f_gc},

{"__tostring", f_tostring},

{NULL, NULL}

};

static void createmeta (lua_State *L) {

luaL_newmetatable(L, LUA_FILEHANDLE); /* metatable for file handles */

luaL_setfuncs(L, metameth, 0); /* add metamethods to new metatable */

luaL_newlibtable(L, meth); /* create method table */

luaL_setfuncs(L, meth, 0); /* add file methods to method table */

lua_setfield(L, -2, "__index"); /* metatable.__index = method table */

lua_pop(L, 1); /* pop 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 */

luaL_pushfail(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;

}

lua55c/src/liolib.c at main · 2MoonsLua/lua55c · GitHub

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