[proxmark3-svn] / liblua / liolib.c

/*
** $Id: liolib.c,v 2.111 2013/03/21 13:57:27 roberto Exp $
** Standard I/O (and system) library
** See Copyright Notice in lua.h
*/


/*
** POSIX idiosyncrasy!
** This definition must come before the inclusion of 'stdio.h'; it
** should not affect non-POSIX systems
*/
#if !defined(_FILE_OFFSET_BITS)
#define _FILE_OFFSET_BITS 64
#endif


#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define liolib_c
#define LUA_LIB

#include "lua.h"

#include "lauxlib.h"
#include "lualib.h"


#if !defined(lua_checkmode)

/*
** Check whether 'mode' matches '[rwa]%+?b?'.
** Change this macro to accept other modes for 'fopen' besides
** the standard ones.
*/
#define lua_checkmode(mode) \
	(*mode != '\0' && strchr("rwa", *(mode++)) != NULL &&	\
	(*mode != '+' || ++mode) &&  /* skip if char is '+' */	\
	(*mode != 'b' || ++mode) &&  /* skip if char is 'b' */	\
	(*mode == '\0'))

#endif

/*
** {======================================================
** lua_popen spawns a new process connected to the current
** one through the file streams.
** =======================================================
*/

#if !defined(lua_popen)	/* { */

#if defined(LUA_USE_POPEN)	/* { */

#define lua_popen(L,c,m)	((void)L, fflush(NULL), popen(c,m))
#define lua_pclose(L,file)	((void)L, pclose(file))

#elif defined(LUA_WIN)		/* }{ */

#define lua_popen(L,c,m)		((void)L, _popen(c,m))
#define lua_pclose(L,file)		((void)L, _pclose(file))


#else				/* }{ */

#define lua_popen(L,c,m)		((void)((void)c, m),  \
		luaL_error(L, LUA_QL("popen") " not supported"), (FILE*)0)
#define lua_pclose(L,file)		((void)((void)L, file), -1)


#endif				/* } */

#endif			/* } */

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


/*
** {======================================================
** lua_fseek/lua_ftell: configuration for longer offsets
** =======================================================
*/

#if !defined(lua_fseek)	/* { */

#if defined(LUA_USE_POSIX)

#define l_fseek(f,o,w)		fseeko(f,o,w)
#define l_ftell(f)		ftello(f)
#define l_seeknum		off_t

#elif defined(LUA_WIN) && !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

#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 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
** file is not left opened.
*/
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;
}


static int aux_close (lua_State *L) {
  LStream *p = tolstream(L);
  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 " LUA_QS " (%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, lua_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, lua_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 = lua_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 + strlen(IO_PREFIX));
  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);


static void aux_lines (lua_State *L, int toclose) {
  int i;
  int n = lua_gettop(L) - 1;  /* number of arguments to read */
  /* ensure that arguments will fit here and into 'io_readline' stack */
  luaL_argcheck(L, n <= LUA_MINSTACK - 3, LUA_MINSTACK - 3, "too many options");
  lua_pushvalue(L, 1);  /* file handle */
  lua_pushinteger(L, n);  /* number of arguments to read */
  lua_pushboolean(L, toclose);  /* close/not close file when finished */
  for (i = 1; i <= n; i++) lua_pushvalue(L, i + 1);  /* copy arguments */
  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
** =======================================================
*/


static int read_number (lua_State *L, FILE *f) {
  lua_Number d;
  if (fscanf(f, LUA_NUMBER_SCAN, &d) == 1) {
    lua_pushnumber(L, d);
    return 1;
  }
  else {
   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);
  lua_pushlstring(L, NULL, 0);
  return (c != EOF);
}


static int read_line (lua_State *L, FILE *f, int chop) {
  luaL_Buffer b;
  luaL_buffinit(L, &b);
  for (;;) {
    size_t l;
    char *p = luaL_prepbuffer(&b);
    if (fgets(p, LUAL_BUFFERSIZE, f) == NULL) {  /* eof? */
      luaL_pushresult(&b);  /* close buffer */
      return (lua_rawlen(L, -1) > 0);  /* check whether read something */
    }
    l = strlen(p);
    if (l == 0 || p[l-1] != '\n')
      luaL_addsize(&b, l);
    else {
      luaL_addsize(&b, l - chop);  /* chop 'eol' if needed */
      luaL_pushresult(&b);  /* close buffer */
      return 1;  /* read at least an `eol' */
    }
  }
}


#define MAX_SIZE_T	(~(size_t)0)

static void read_all (lua_State *L, FILE *f) {
  size_t rlen = LUAL_BUFFERSIZE;  /* how much to read in each cycle */
  luaL_Buffer b;
  luaL_buffinit(L, &b);
  for (;;) {
    char *p = luaL_prepbuffsize(&b, rlen);
    size_t nr = fread(p, sizeof(char), rlen, f);
    luaL_addsize(&b, nr);
    if (nr < rlen) break;  /* eof? */
    else if (rlen <= (MAX_SIZE_T / 4))  /* avoid buffers too large */
      rlen *= 2;  /* double buffer size at each iteration */
  }
  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)lua_tointeger(L, n);
        success = (l == 0) ? test_eof(L, f) : read_chars(L, f, l);
      }
      else {
        const char *p = lua_tostring(L, n);
        luaL_argcheck(L, p && p[0] == '*', n, "invalid option");
        switch (p[1]) {
          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);
  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_isnil(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 */
      status = status &&
          fprintf(f, LUA_NUMBER_FMT, lua_tonumber(L, arg)) > 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_Number p3 = luaL_optnumber(L, 3, 0);
  l_seeknum offset = (l_seeknum)p3;
  luaL_argcheck(L, (lua_Number)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_pushnumber(L, (lua_Number)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], 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;
}
Commit	Line	Data
ba8b5c17	1	/*
	2	** $Id: liolib.c,v 2.111 2013/03/21 13:57:27 roberto Exp $
	3	** Standard I/O (and system) library
	4	** See Copyright Notice in lua.h
	5	*/
	6
	7
	8	/*
	9	** POSIX idiosyncrasy!
	10	** This definition must come before the inclusion of 'stdio.h'; it
	11	** should not affect non-POSIX systems
	12	*/
	13	#if !defined(_FILE_OFFSET_BITS)
	14	#define _FILE_OFFSET_BITS 64
	15	#endif
	16
	17
	18	#include <errno.h>
	19	#include <stdio.h>
	20	#include <stdlib.h>
	21	#include <string.h>
	22
	23	#define liolib_c
	24	#define LUA_LIB
	25
	26	#include "lua.h"
	27
	28	#include "lauxlib.h"
	29	#include "lualib.h"
	30
	31
	32	#if !defined(lua_checkmode)
	33
	34	/*
	35	** Check whether 'mode' matches '[rwa]%+?b?'.
	36	** Change this macro to accept other modes for 'fopen' besides
	37	** the standard ones.
	38	*/
	39	#define lua_checkmode(mode) \
	40	(mode != '\0' && strchr("rwa", (mode++)) != NULL && \
	41	(mode != '+' \|\| ++mode) && / skip if char is '+' */ \
	42	(mode != 'b' \|\| ++mode) && / skip if char is 'b' */ \
	43	(*mode == '\0'))
	44
	45	#endif
	46
	47	/*
	48	** {======================================================
	49	** lua_popen spawns a new process connected to the current
	50	** one through the file streams.
	51	** =======================================================
	52	*/
	53
	54	#if !defined(lua_popen) /* { */
	55
	56	#if defined(LUA_USE_POPEN) /* { */
	57
	58	#define lua_popen(L,c,m) ((void)L, fflush(NULL), popen(c,m))
	59	#define lua_pclose(L,file) ((void)L, pclose(file))
	60
	61	#elif defined(LUA_WIN) /* }{ */
	62
	63	#define lua_popen(L,c,m) ((void)L, _popen(c,m))
	64	#define lua_pclose(L,file) ((void)L, _pclose(file))
65
66
67	#else /* }{ */
68
69	#define lua_popen(L,c,m) ((void)((void)c, m), \
70	luaL_error(L, LUA_QL("popen") " not supported"), (FILE*)0)
71	#define lua_pclose(L,file) ((void)((void)L, file), -1)
72
73
74	#endif /* } */
75
76	#endif /* } */
77
78	/* }====================================================== */
79
80
81	/*
82	** {======================================================
83	** lua_fseek/lua_ftell: configuration for longer offsets
84	** =======================================================
85	*/
86
87	#if !defined(lua_fseek) /* { */
88
89	#if defined(LUA_USE_POSIX)
90
91	#define l_fseek(f,o,w) fseeko(f,o,w)
92	#define l_ftell(f) ftello(f)
93	#define l_seeknum off_t
94
95	#elif defined(LUA_WIN) && !defined(_CRTIMP_TYPEINFO) \
96	&& defined(_MSC_VER) && (_MSC_VER >= 1400)
97	/* Windows (but not DDK) and Visual C++ 2005 or higher */
98
99	#define l_fseek(f,o,w) _fseeki64(f,o,w)
100	#define l_ftell(f) _ftelli64(f)
101	#define l_seeknum __int64
102
103	#else
104
105	#define l_fseek(f,o,w) fseek(f,o,w)
106	#define l_ftell(f) ftell(f)
107	#define l_seeknum long
108
109	#endif
110
111	#endif /* } */
112
113	/* }====================================================== */
114
115
116	#define IO_PREFIX "_IO_"
117	#define IO_INPUT (IO_PREFIX "input")
118	#define IO_OUTPUT (IO_PREFIX "output")
119
120
121	typedef luaL_Stream LStream;
122
123
124	#define tolstream(L) ((LStream *)luaL_checkudata(L, 1, LUA_FILEHANDLE))
125
126	#define isclosed(p) ((p)->closef == NULL)
127
128
129	static int io_type (lua_State *L) {
130	LStream *p;
131	luaL_checkany(L, 1);
132	p = (LStream *)luaL_testudata(L, 1, LUA_FILEHANDLE);
133	if (p == NULL)
134	lua_pushnil(L); /* not a file */
135	else if (isclosed(p))
136	lua_pushliteral(L, "closed file");
137	else
138	lua_pushliteral(L, "file");
139	return 1;
140	}
141
142
143	static int f_tostring (lua_State *L) {
144	LStream *p = tolstream(L);
145	if (isclosed(p))
146	lua_pushliteral(L, "file (closed)");
147	else
148	lua_pushfstring(L, "file (%p)", p->f);
149	return 1;
150	}
151
152
153	static FILE tofile (lua_State L) {
154	LStream *p = tolstream(L);
155	if (isclosed(p))
156	luaL_error(L, "attempt to use a closed file");
157	lua_assert(p->f);
158	return p->f;
159	}
160
161
162	/*
163	** When creating file handles, always creates a `closed' file handle
164	** before opening the actual file; so, if there is a memory error, the
165	** file is not left opened.
166	*/
167	static LStream newprefile (lua_State L) {
168	LStream p = (LStream )lua_newuserdata(L, sizeof(LStream));
169	p->closef = NULL; /* mark file handle as 'closed' */
170	luaL_setmetatable(L, LUA_FILEHANDLE);
171	return p;
172	}
173
174
175	static int aux_close (lua_State *L) {
176	LStream *p = tolstream(L);
177	lua_CFunction cf = p->closef;
178	p->closef = NULL; /* mark stream as closed */
179	return (cf)(L); / close it */
180	}
181
182
183	static int io_close (lua_State *L) {
184	if (lua_isnone(L, 1)) /* no argument? */
185	lua_getfield(L, LUA_REGISTRYINDEX, IO_OUTPUT); /* use standard output */
186	tofile(L); /* make sure argument is an open stream */
187	return aux_close(L);
188	}
189
190
191	static int f_gc (lua_State *L) {
192	LStream *p = tolstream(L);
193	if (!isclosed(p) && p->f != NULL)
194	aux_close(L); /* ignore closed and incompletely open files */
195	return 0;
196	}
197
198
199	/*
200	** function to close regular files
201	*/
202	static int io_fclose (lua_State *L) {
203	LStream *p = tolstream(L);
204	int res = fclose(p->f);
205	return luaL_fileresult(L, (res == 0), NULL);
206	}
207
208
209	static LStream newfile (lua_State L) {
210	LStream *p = newprefile(L);
211	p->f = NULL;
212	p->closef = &io_fclose;
213	return p;
214	}
215
216
217	static void opencheck (lua_State L, const char fname, const char *mode) {
218	LStream *p = newfile(L);
219	p->f = fopen(fname, mode);
220	if (p->f == NULL)
221	luaL_error(L, "cannot open file " LUA_QS " (%s)", fname, strerror(errno));
222	}
223
224
225	static int io_open (lua_State *L) {
226	const char *filename = luaL_checkstring(L, 1);
227	const char *mode = luaL_optstring(L, 2, "r");
228	LStream *p = newfile(L);
229	const char md = mode; / to traverse/check mode */
230	luaL_argcheck(L, lua_checkmode(md), 2, "invalid mode");
231	p->f = fopen(filename, mode);
232	return (p->f == NULL) ? luaL_fileresult(L, 0, filename) : 1;
233	}
234
235
236	/*
237	** function to close 'popen' files
238	*/
239	static int io_pclose (lua_State *L) {
240	LStream *p = tolstream(L);
241	return luaL_execresult(L, lua_pclose(L, p->f));
242	}
243
244
245	static int io_popen (lua_State *L) {
246	const char *filename = luaL_checkstring(L, 1);
247	const char *mode = luaL_optstring(L, 2, "r");
248	LStream *p = newprefile(L);
249	p->f = lua_popen(L, filename, mode);
250	p->closef = &io_pclose;
251	return (p->f == NULL) ? luaL_fileresult(L, 0, filename) : 1;
252	}
253
254
255	static int io_tmpfile (lua_State *L) {
256	LStream *p = newfile(L);
257	p->f = tmpfile();
258	return (p->f == NULL) ? luaL_fileresult(L, 0, NULL) : 1;
259	}
260
261
262	static FILE getiofile (lua_State L, const char *findex) {
263	LStream *p;
264	lua_getfield(L, LUA_REGISTRYINDEX, findex);
265	p = (LStream *)lua_touserdata(L, -1);
266	if (isclosed(p))
267	luaL_error(L, "standard %s file is closed", findex + strlen(IO_PREFIX));
268	return p->f;
269	}
270
271
272	static int g_iofile (lua_State L, const char f, const char *mode) {
273	if (!lua_isnoneornil(L, 1)) {
274	const char *filename = lua_tostring(L, 1);
275	if (filename)
276	opencheck(L, filename, mode);
277	else {
278	tofile(L); /* check that it's a valid file handle */
279	lua_pushvalue(L, 1);
280	}
281	lua_setfield(L, LUA_REGISTRYINDEX, f);
282	}
283	/* return current value */
284	lua_getfield(L, LUA_REGISTRYINDEX, f);
285	return 1;
286	}
287
288
289	static int io_input (lua_State *L) {
290	return g_iofile(L, IO_INPUT, "r");
291	}
292
293
294	static int io_output (lua_State *L) {
295	return g_iofile(L, IO_OUTPUT, "w");
296	}
297
298
299	static int io_readline (lua_State *L);
300
301
302	static void aux_lines (lua_State *L, int toclose) {
303	int i;
304	int n = lua_gettop(L) - 1; /* number of arguments to read */
305	/* ensure that arguments will fit here and into 'io_readline' stack */
306	luaL_argcheck(L, n <= LUA_MINSTACK - 3, LUA_MINSTACK - 3, "too many options");
307	lua_pushvalue(L, 1); /* file handle */
308	lua_pushinteger(L, n); /* number of arguments to read */
309	lua_pushboolean(L, toclose); /* close/not close file when finished */
310	for (i = 1; i <= n; i++) lua_pushvalue(L, i + 1); /* copy arguments */
311	lua_pushcclosure(L, io_readline, 3 + n);
312	}
313
314
315	static int f_lines (lua_State *L) {
316	tofile(L); /* check that it's a valid file handle */
317	aux_lines(L, 0);
318	return 1;
319	}
320
321
322	static int io_lines (lua_State *L) {
323	int toclose;
324	if (lua_isnone(L, 1)) lua_pushnil(L); /* at least one argument */
325	if (lua_isnil(L, 1)) { /* no file name? */
326	lua_getfield(L, LUA_REGISTRYINDEX, IO_INPUT); /* get default input */
327	lua_replace(L, 1); /* put it at index 1 */
328	tofile(L); /* check that it's a valid file handle */
329	toclose = 0; /* do not close it after iteration */
330	}
331	else { /* open a new file */
332	const char *filename = luaL_checkstring(L, 1);
333	opencheck(L, filename, "r");
334	lua_replace(L, 1); /* put file at index 1 */
335	toclose = 1; /* close it after iteration */
336	}
337	aux_lines(L, toclose);
338	return 1;
339	}
340
341
342	/*
343	** {======================================================
344	** READ
345	** =======================================================
346	*/
347
348
349	static int read_number (lua_State L, FILE f) {
350	lua_Number d;
351	if (fscanf(f, LUA_NUMBER_SCAN, &d) == 1) {
352	lua_pushnumber(L, d);
353	return 1;
354	}
355	else {
356	lua_pushnil(L); /* "result" to be removed */
357	return 0; /* read fails */
358	}
359	}
360
361
362	static int test_eof (lua_State L, FILE f) {
363	int c = getc(f);
364	ungetc(c, f);
365	lua_pushlstring(L, NULL, 0);
366	return (c != EOF);
367	}
368
369
370	static int read_line (lua_State L, FILE f, int chop) {
371	luaL_Buffer b;
372	luaL_buffinit(L, &b);
373	for (;;) {
374	size_t l;
375	char *p = luaL_prepbuffer(&b);
376	if (fgets(p, LUAL_BUFFERSIZE, f) == NULL) { /* eof? */
377	luaL_pushresult(&b); /* close buffer */
378	return (lua_rawlen(L, -1) > 0); /* check whether read something */
379	}
380	l = strlen(p);
381	if (l == 0 \|\| p[l-1] != '\n')
382	luaL_addsize(&b, l);
383	else {
384	luaL_addsize(&b, l - chop); /* chop 'eol' if needed */
385	luaL_pushresult(&b); /* close buffer */
386	return 1; /* read at least an `eol' */
387	}
388	}
389	}
390
391
392	#define MAX_SIZE_T (~(size_t)0)
393
394	static void read_all (lua_State L, FILE f) {
395	size_t rlen = LUAL_BUFFERSIZE; /* how much to read in each cycle */
396	luaL_Buffer b;
397	luaL_buffinit(L, &b);
398	for (;;) {
399	char *p = luaL_prepbuffsize(&b, rlen);
400	size_t nr = fread(p, sizeof(char), rlen, f);
401	luaL_addsize(&b, nr);
402	if (nr < rlen) break; /* eof? */
403	else if (rlen <= (MAX_SIZE_T / 4)) /* avoid buffers too large */
404	rlen = 2; / double buffer size at each iteration */
405	}
406	luaL_pushresult(&b); /* close buffer */
407	}
408
409
410	static int read_chars (lua_State L, FILE f, size_t n) {
411	size_t nr; /* number of chars actually read */
412	char *p;
413	luaL_Buffer b;
414	luaL_buffinit(L, &b);
415	p = luaL_prepbuffsize(&b, n); /* prepare buffer to read whole block */
416	nr = fread(p, sizeof(char), n, f); /* try to read 'n' chars */
417	luaL_addsize(&b, nr);
418	luaL_pushresult(&b); /* close buffer */
419	return (nr > 0); /* true iff read something */
420	}
421
422
423	static int g_read (lua_State L, FILE f, int first) {
424	int nargs = lua_gettop(L) - 1;
425	int success;
426	int n;
427	clearerr(f);
428	if (nargs == 0) { /* no arguments? */
429	success = read_line(L, f, 1);
430	n = first+1; /* to return 1 result */
431	}
432	else { /* ensure stack space for all results and for auxlib's buffer */
433	luaL_checkstack(L, nargs+LUA_MINSTACK, "too many arguments");
434	success = 1;
435	for (n = first; nargs-- && success; n++) {
436	if (lua_type(L, n) == LUA_TNUMBER) {
437	size_t l = (size_t)lua_tointeger(L, n);
438	success = (l == 0) ? test_eof(L, f) : read_chars(L, f, l);
439	}
440	else {
441	const char *p = lua_tostring(L, n);
442	luaL_argcheck(L, p && p[0] == '*', n, "invalid option");
443	switch (p[1]) {
444	case 'n': /* number */
445	success = read_number(L, f);
446	break;
447	case 'l': /* line */
448	success = read_line(L, f, 1);
449	break;
450	case 'L': /* line with end-of-line */
451	success = read_line(L, f, 0);
452	break;
453	case 'a': /* file */
454	read_all(L, f); /* read entire file */
455	success = 1; /* always success */
456	break;
457	default:
458	return luaL_argerror(L, n, "invalid format");
459	}
460	}
461	}
462	}
463	if (ferror(f))
464	return luaL_fileresult(L, 0, NULL);
465	if (!success) {
466	lua_pop(L, 1); /* remove last result */
467	lua_pushnil(L); /* push nil instead */
468	}
469	return n - first;
470	}
471
472
473	static int io_read (lua_State *L) {
474	return g_read(L, getiofile(L, IO_INPUT), 1);
475	}
476
477
478	static int f_read (lua_State *L) {
479	return g_read(L, tofile(L), 2);
480	}
481
482
483	static int io_readline (lua_State *L) {
484	LStream p = (LStream )lua_touserdata(L, lua_upvalueindex(1));
485	int i;
486	int n = (int)lua_tointeger(L, lua_upvalueindex(2));
487	if (isclosed(p)) /* file is already closed? */
488	return luaL_error(L, "file is already closed");
489	lua_settop(L , 1);
490	for (i = 1; i <= n; i++) /* push arguments to 'g_read' */
491	lua_pushvalue(L, lua_upvalueindex(3 + i));
492	n = g_read(L, p->f, 2); /* 'n' is number of results */
493	lua_assert(n > 0); /* should return at least a nil */
494	if (!lua_isnil(L, -n)) /* read at least one value? */
495	return n; /* return them */
496	else { /* first result is nil: EOF or error */
497	if (n > 1) { /* is there error information? */
498	/* 2nd result is error message */
499	return luaL_error(L, "%s", lua_tostring(L, -n + 1));
500	}
501	if (lua_toboolean(L, lua_upvalueindex(3))) { /* generator created file? */
502	lua_settop(L, 0);
503	lua_pushvalue(L, lua_upvalueindex(1));
504	aux_close(L); /* close it */
505	}
506	return 0;
507	}
508	}
509
510	/* }====================================================== */
511
512
513	static int g_write (lua_State L, FILE f, int arg) {
514	int nargs = lua_gettop(L) - arg;
515	int status = 1;
516	for (; nargs--; arg++) {
517	if (lua_type(L, arg) == LUA_TNUMBER) {
518	/* optimization: could be done exactly as for strings */
519	status = status &&
520	fprintf(f, LUA_NUMBER_FMT, lua_tonumber(L, arg)) > 0;
521	}
522	else {
523	size_t l;
524	const char *s = luaL_checklstring(L, arg, &l);
525	status = status && (fwrite(s, sizeof(char), l, f) == l);
526	}
527	}
528	if (status) return 1; /* file handle already on stack top */
529	else return luaL_fileresult(L, status, NULL);
530	}
531
532
533	static int io_write (lua_State *L) {
534	return g_write(L, getiofile(L, IO_OUTPUT), 1);
535	}
536
537
538	static int f_write (lua_State *L) {
539	FILE *f = tofile(L);
540	lua_pushvalue(L, 1); /* push file at the stack top (to be returned) */
541	return g_write(L, f, 2);
542	}
543
544
545	static int f_seek (lua_State *L) {
546	static const int mode[] = {SEEK_SET, SEEK_CUR, SEEK_END};
547	static const char *const modenames[] = {"set", "cur", "end", NULL};
548	FILE *f = tofile(L);
549	int op = luaL_checkoption(L, 2, "cur", modenames);
550	lua_Number p3 = luaL_optnumber(L, 3, 0);
551	l_seeknum offset = (l_seeknum)p3;
552	luaL_argcheck(L, (lua_Number)offset == p3, 3,
553	"not an integer in proper range");
554	op = l_fseek(f, offset, mode[op]);
555	if (op)
556	return luaL_fileresult(L, 0, NULL); /* error */
557	else {
558	lua_pushnumber(L, (lua_Number)l_ftell(f));
559	return 1;
560	}
561	}
562
563
564	static int f_setvbuf (lua_State *L) {
565	static const int mode[] = {_IONBF, _IOFBF, _IOLBF};
566	static const char *const modenames[] = {"no", "full", "line", NULL};
567	FILE *f = tofile(L);
568	int op = luaL_checkoption(L, 2, NULL, modenames);
569	lua_Integer sz = luaL_optinteger(L, 3, LUAL_BUFFERSIZE);
570	int res = setvbuf(f, NULL, mode[op], sz);
571	return luaL_fileresult(L, res == 0, NULL);
572	}
573
574
575
576	static int io_flush (lua_State *L) {
577	return luaL_fileresult(L, fflush(getiofile(L, IO_OUTPUT)) == 0, NULL);
578	}
579
580
581	static int f_flush (lua_State *L) {
582	return luaL_fileresult(L, fflush(tofile(L)) == 0, NULL);
583	}
584
585
586	/*
587	** functions for 'io' library
588	*/
589	static const luaL_Reg iolib[] = {
590	{"close", io_close},
591	{"flush", io_flush},
592	{"input", io_input},
593	{"lines", io_lines},
594	{"open", io_open},
595	{"output", io_output},
596	{"popen", io_popen},
597	{"read", io_read},
598	{"tmpfile", io_tmpfile},
599	{"type", io_type},
600	{"write", io_write},
601	{NULL, NULL}
602	};
603
604
605	/*
606	** methods for file handles
607	*/
608	static const luaL_Reg flib[] = {
609	{"close", io_close},
610	{"flush", f_flush},
611	{"lines", f_lines},
612	{"read", f_read},
613	{"seek", f_seek},
614	{"setvbuf", f_setvbuf},
615	{"write", f_write},
616	{"__gc", f_gc},
617	{"__tostring", f_tostring},
618	{NULL, NULL}
619	};
620
621
622	static void createmeta (lua_State *L) {
623	luaL_newmetatable(L, LUA_FILEHANDLE); /* create metatable for file handles */
624	lua_pushvalue(L, -1); /* push metatable */
625	lua_setfield(L, -2, "__index"); /* metatable.__index = metatable */
626	luaL_setfuncs(L, flib, 0); /* add file methods to new metatable */
627	lua_pop(L, 1); /* pop new metatable */
628	}
629
630
631	/*
632	** function to (not) close the standard files stdin, stdout, and stderr
633	*/
634	static int io_noclose (lua_State *L) {
635	LStream *p = tolstream(L);
636	p->closef = &io_noclose; /* keep file opened */
637	lua_pushnil(L);
638	lua_pushliteral(L, "cannot close standard file");
639	return 2;
640	}
641
642
643	static void createstdfile (lua_State L, FILE f, const char *k,
644	const char *fname) {
645	LStream *p = newprefile(L);
646	p->f = f;
647	p->closef = &io_noclose;
648	if (k != NULL) {
649	lua_pushvalue(L, -1);
650	lua_setfield(L, LUA_REGISTRYINDEX, k); /* add file to registry */
651	}
652	lua_setfield(L, -2, fname); /* add file to module */
653	}
654
655
656	LUAMOD_API int luaopen_io (lua_State *L) {
657	luaL_newlib(L, iolib); /* new module */
658	createmeta(L);
659	/* create (and set) default files */
660	createstdfile(L, stdin, IO_INPUT, "stdin");
661	createstdfile(L, stdout, IO_OUTPUT, "stdout");
662	createstdfile(L, stderr, NULL, "stderr");
663	return 1;
664	}
665