rlm@1: /*
rlm@1: ** $Id: liolib.c,v 2.73.1.3 2008/01/18 17:47:43 roberto Exp $
rlm@1: ** Standard I/O (and system) library
rlm@1: ** See Copyright Notice in lua.h
rlm@1: */
rlm@1: 
rlm@1: 
rlm@1: #include <errno.h>
rlm@1: #include <stdio.h>
rlm@1: #include <stdlib.h>
rlm@1: #include <string.h>
rlm@1: 
rlm@1: #define liolib_c
rlm@1: #define LUA_LIB
rlm@1: 
rlm@1: #include "lua.h"
rlm@1: 
rlm@1: #include "lauxlib.h"
rlm@1: #include "lualib.h"
rlm@1: 
rlm@1: 
rlm@1: 
rlm@1: #define IO_INPUT	1
rlm@1: #define IO_OUTPUT	2
rlm@1: 
rlm@1: 
rlm@1: static const char *const fnames[] = {"input", "output"};
rlm@1: 
rlm@1: 
rlm@1: static int pushresult (lua_State *L, int i, const char *filename) {
rlm@1:   int en = errno;  /* calls to Lua API may change this value */
rlm@1:   if (i) {
rlm@1:     lua_pushboolean(L, 1);
rlm@1:     return 1;
rlm@1:   }
rlm@1:   else {
rlm@1:     lua_pushnil(L);
rlm@1:     if (filename)
rlm@1:       lua_pushfstring(L, "%s: %s", filename, strerror(en));
rlm@1:     else
rlm@1:       lua_pushfstring(L, "%s", strerror(en));
rlm@1:     lua_pushinteger(L, en);
rlm@1:     return 3;
rlm@1:   }
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static void fileerror (lua_State *L, int arg, const char *filename) {
rlm@1:   lua_pushfstring(L, "%s: %s", filename, strerror(errno));
rlm@1:   luaL_argerror(L, arg, lua_tostring(L, -1));
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: #define tofilep(L)	((FILE **)luaL_checkudata(L, 1, LUA_FILEHANDLE))
rlm@1: 
rlm@1: 
rlm@1: static int io_type (lua_State *L) {
rlm@1:   void *ud;
rlm@1:   luaL_checkany(L, 1);
rlm@1:   ud = lua_touserdata(L, 1);
rlm@1:   lua_getfield(L, LUA_REGISTRYINDEX, LUA_FILEHANDLE);
rlm@1:   if (ud == NULL || !lua_getmetatable(L, 1) || !lua_rawequal(L, -2, -1))
rlm@1:     lua_pushnil(L);  /* not a file */
rlm@1:   else if (*((FILE **)ud) == NULL)
rlm@1:     lua_pushliteral(L, "closed file");
rlm@1:   else
rlm@1:     lua_pushliteral(L, "file");
rlm@1:   return 1;
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static FILE *tofile (lua_State *L) {
rlm@1:   FILE **f = tofilep(L);
rlm@1:   if (*f == NULL)
rlm@1:     luaL_error(L, "attempt to use a closed file");
rlm@1:   return *f;
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: 
rlm@1: /*
rlm@1: ** When creating file handles, always creates a `closed' file handle
rlm@1: ** before opening the actual file; so, if there is a memory error, the
rlm@1: ** file is not left opened.
rlm@1: */
rlm@1: static FILE **newfile (lua_State *L) {
rlm@1:   FILE **pf = (FILE **)lua_newuserdata(L, sizeof(FILE *));
rlm@1:   *pf = NULL;  /* file handle is currently `closed' */
rlm@1:   luaL_getmetatable(L, LUA_FILEHANDLE);
rlm@1:   lua_setmetatable(L, -2);
rlm@1:   return pf;
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: /*
rlm@1: ** function to (not) close the standard files stdin, stdout, and stderr
rlm@1: */
rlm@1: static int io_noclose (lua_State *L) {
rlm@1:   lua_pushnil(L);
rlm@1:   lua_pushliteral(L, "cannot close standard file");
rlm@1:   return 2;
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: /*
rlm@1: ** function to close 'popen' files
rlm@1: */
rlm@1: static int io_pclose (lua_State *L) {
rlm@1:   FILE **p = tofilep(L);
rlm@1:   int ok = lua_pclose(L, *p);
rlm@1:   *p = NULL;
rlm@1:   return pushresult(L, ok, NULL);
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: /*
rlm@1: ** function to close regular files
rlm@1: */
rlm@1: static int io_fclose (lua_State *L) {
rlm@1:   FILE **p = tofilep(L);
rlm@1:   int ok = (fclose(*p) == 0);
rlm@1:   *p = NULL;
rlm@1:   return pushresult(L, ok, NULL);
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int aux_close (lua_State *L) {
rlm@1:   lua_getfenv(L, 1);
rlm@1:   lua_getfield(L, -1, "__close");
rlm@1:   return (lua_tocfunction(L, -1))(L);
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int io_close (lua_State *L) {
rlm@1:   if (lua_isnone(L, 1))
rlm@1:     lua_rawgeti(L, LUA_ENVIRONINDEX, IO_OUTPUT);
rlm@1:   tofile(L);  /* make sure argument is a file */
rlm@1:   return aux_close(L);
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int io_gc (lua_State *L) {
rlm@1:   FILE *f = *tofilep(L);
rlm@1:   /* ignore closed files */
rlm@1:   if (f != NULL)
rlm@1:     aux_close(L);
rlm@1:   return 0;
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int io_tostring (lua_State *L) {
rlm@1:   FILE *f = *tofilep(L);
rlm@1:   if (f == NULL)
rlm@1:     lua_pushliteral(L, "file (closed)");
rlm@1:   else
rlm@1:     lua_pushfstring(L, "file (%p)", f);
rlm@1:   return 1;
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int io_open (lua_State *L) {
rlm@1:   const char *filename = luaL_checkstring(L, 1);
rlm@1:   const char *mode = luaL_optstring(L, 2, "r");
rlm@1:   FILE **pf = newfile(L);
rlm@1:   *pf = fopen(filename, mode);
rlm@1:   return (*pf == NULL) ? pushresult(L, 0, filename) : 1;
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: /*
rlm@1: ** this function has a separated environment, which defines the
rlm@1: ** correct __close for 'popen' files
rlm@1: */
rlm@1: static int io_popen (lua_State *L) {
rlm@1:   const char *filename = luaL_checkstring(L, 1);
rlm@1:   const char *mode = luaL_optstring(L, 2, "r");
rlm@1:   FILE **pf = newfile(L);
rlm@1:   *pf = lua_popen(L, filename, mode);
rlm@1:   return (*pf == NULL) ? pushresult(L, 0, filename) : 1;
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int io_tmpfile (lua_State *L) {
rlm@1:   FILE **pf = newfile(L);
rlm@1:   *pf = tmpfile();
rlm@1:   return (*pf == NULL) ? pushresult(L, 0, NULL) : 1;
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static FILE *getiofile (lua_State *L, int findex) {
rlm@1:   FILE *f;
rlm@1:   lua_rawgeti(L, LUA_ENVIRONINDEX, findex);
rlm@1:   f = *(FILE **)lua_touserdata(L, -1);
rlm@1:   if (f == NULL)
rlm@1:     luaL_error(L, "standard %s file is closed", fnames[findex - 1]);
rlm@1:   return f;
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int g_iofile (lua_State *L, int f, const char *mode) {
rlm@1:   if (!lua_isnoneornil(L, 1)) {
rlm@1:     const char *filename = lua_tostring(L, 1);
rlm@1:     if (filename) {
rlm@1:       FILE **pf = newfile(L);
rlm@1:       *pf = fopen(filename, mode);
rlm@1:       if (*pf == NULL)
rlm@1:         fileerror(L, 1, filename);
rlm@1:     }
rlm@1:     else {
rlm@1:       tofile(L);  /* check that it's a valid file handle */
rlm@1:       lua_pushvalue(L, 1);
rlm@1:     }
rlm@1:     lua_rawseti(L, LUA_ENVIRONINDEX, f);
rlm@1:   }
rlm@1:   /* return current value */
rlm@1:   lua_rawgeti(L, LUA_ENVIRONINDEX, f);
rlm@1:   return 1;
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int io_input (lua_State *L) {
rlm@1:   return g_iofile(L, IO_INPUT, "r");
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int io_output (lua_State *L) {
rlm@1:   return g_iofile(L, IO_OUTPUT, "w");
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int io_readline (lua_State *L);
rlm@1: 
rlm@1: 
rlm@1: static void aux_lines (lua_State *L, int idx, int toclose) {
rlm@1:   lua_pushvalue(L, idx);
rlm@1:   lua_pushboolean(L, toclose);  /* close/not close file when finished */
rlm@1:   lua_pushcclosure(L, io_readline, 2);
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int f_lines (lua_State *L) {
rlm@1:   tofile(L);  /* check that it's a valid file handle */
rlm@1:   aux_lines(L, 1, 0);
rlm@1:   return 1;
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int io_lines (lua_State *L) {
rlm@1:   if (lua_isnoneornil(L, 1)) {  /* no arguments? */
rlm@1:     /* will iterate over default input */
rlm@1:     lua_rawgeti(L, LUA_ENVIRONINDEX, IO_INPUT);
rlm@1:     return f_lines(L);
rlm@1:   }
rlm@1:   else {
rlm@1:     const char *filename = luaL_checkstring(L, 1);
rlm@1:     FILE **pf = newfile(L);
rlm@1:     *pf = fopen(filename, "r");
rlm@1:     if (*pf == NULL)
rlm@1:       fileerror(L, 1, filename);
rlm@1:     aux_lines(L, lua_gettop(L), 1);
rlm@1:     return 1;
rlm@1:   }
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: /*
rlm@1: ** {======================================================
rlm@1: ** READ
rlm@1: ** =======================================================
rlm@1: */
rlm@1: 
rlm@1: 
rlm@1: static int read_number (lua_State *L, FILE *f) {
rlm@1:   lua_Number d;
rlm@1:   if (fscanf(f, LUA_NUMBER_SCAN, &d) == 1) {
rlm@1:     lua_pushnumber(L, d);
rlm@1:     return 1;
rlm@1:   }
rlm@1:   else return 0;  /* read fails */
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int test_eof (lua_State *L, FILE *f) {
rlm@1:   int c = getc(f);
rlm@1:   ungetc(c, f);
rlm@1:   lua_pushlstring(L, NULL, 0);
rlm@1:   return (c != EOF);
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int read_line (lua_State *L, FILE *f) {
rlm@1:   luaL_Buffer b;
rlm@1:   luaL_buffinit(L, &b);
rlm@1:   for (;;) {
rlm@1:     size_t l;
rlm@1:     char *p = luaL_prepbuffer(&b);
rlm@1:     if (fgets(p, LUAL_BUFFERSIZE, f) == NULL) {  /* eof? */
rlm@1:       luaL_pushresult(&b);  /* close buffer */
rlm@1:       return (lua_objlen(L, -1) > 0);  /* check whether read something */
rlm@1:     }
rlm@1:     l = strlen(p);
rlm@1:     if (l == 0 || p[l-1] != '\n')
rlm@1:       luaL_addsize(&b, l);
rlm@1:     else {
rlm@1:       luaL_addsize(&b, l - 1);  /* do not include `eol' */
rlm@1:       luaL_pushresult(&b);  /* close buffer */
rlm@1:       return 1;  /* read at least an `eol' */
rlm@1:     }
rlm@1:   }
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int read_chars (lua_State *L, FILE *f, size_t n) {
rlm@1:   size_t rlen;  /* how much to read */
rlm@1:   size_t nr;  /* number of chars actually read */
rlm@1:   luaL_Buffer b;
rlm@1:   luaL_buffinit(L, &b);
rlm@1:   rlen = LUAL_BUFFERSIZE;  /* try to read that much each time */
rlm@1:   do {
rlm@1:     char *p = luaL_prepbuffer(&b);
rlm@1:     if (rlen > n) rlen = n;  /* cannot read more than asked */
rlm@1:     nr = fread(p, sizeof(char), rlen, f);
rlm@1:     luaL_addsize(&b, nr);
rlm@1:     n -= nr;  /* still have to read `n' chars */
rlm@1:   } while (n > 0 && nr == rlen);  /* until end of count or eof */
rlm@1:   luaL_pushresult(&b);  /* close buffer */
rlm@1:   return (n == 0 || lua_objlen(L, -1) > 0);
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int g_read (lua_State *L, FILE *f, int first) {
rlm@1:   int nargs = lua_gettop(L) - 1;
rlm@1:   int success;
rlm@1:   int n;
rlm@1:   clearerr(f);
rlm@1:   if (nargs == 0) {  /* no arguments? */
rlm@1:     success = read_line(L, f);
rlm@1:     n = first+1;  /* to return 1 result */
rlm@1:   }
rlm@1:   else {  /* ensure stack space for all results and for auxlib's buffer */
rlm@1:     luaL_checkstack(L, nargs+LUA_MINSTACK, "too many arguments");
rlm@1:     success = 1;
rlm@1:     for (n = first; nargs-- && success; n++) {
rlm@1:       if (lua_type(L, n) == LUA_TNUMBER) {
rlm@1:         size_t l = (size_t)lua_tointeger(L, n);
rlm@1:         success = (l == 0) ? test_eof(L, f) : read_chars(L, f, l);
rlm@1:       }
rlm@1:       else {
rlm@1:         const char *p = lua_tostring(L, n);
rlm@1:         luaL_argcheck(L, p && p[0] == '*', n, "invalid option");
rlm@1:         switch (p[1]) {
rlm@1:           case 'n':  /* number */
rlm@1:             success = read_number(L, f);
rlm@1:             break;
rlm@1:           case 'l':  /* line */
rlm@1:             success = read_line(L, f);
rlm@1:             break;
rlm@1:           case 'a':  /* file */
rlm@1:             read_chars(L, f, ~((size_t)0));  /* read MAX_SIZE_T chars */
rlm@1:             success = 1; /* always success */
rlm@1:             break;
rlm@1:           default:
rlm@1:             return luaL_argerror(L, n, "invalid format");
rlm@1:         }
rlm@1:       }
rlm@1:     }
rlm@1:   }
rlm@1:   if (ferror(f))
rlm@1:     return pushresult(L, 0, NULL);
rlm@1:   if (!success) {
rlm@1:     lua_pop(L, 1);  /* remove last result */
rlm@1:     lua_pushnil(L);  /* push nil instead */
rlm@1:   }
rlm@1:   return n - first;
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int io_read (lua_State *L) {
rlm@1:   return g_read(L, getiofile(L, IO_INPUT), 1);
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int f_read (lua_State *L) {
rlm@1:   return g_read(L, tofile(L), 2);
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int io_readline (lua_State *L) {
rlm@1:   FILE *f = *(FILE **)lua_touserdata(L, lua_upvalueindex(1));
rlm@1:   int sucess;
rlm@1:   if (f == NULL)  /* file is already closed? */
rlm@1:     luaL_error(L, "file is already closed");
rlm@1:   sucess = read_line(L, f);
rlm@1:   if (ferror(f))
rlm@1:     return luaL_error(L, "%s", strerror(errno));
rlm@1:   if (sucess) return 1;
rlm@1:   else {  /* EOF */
rlm@1:     if (lua_toboolean(L, lua_upvalueindex(2))) {  /* generator created file? */
rlm@1:       lua_settop(L, 0);
rlm@1:       lua_pushvalue(L, lua_upvalueindex(1));
rlm@1:       aux_close(L);  /* close it */
rlm@1:     }
rlm@1:     return 0;
rlm@1:   }
rlm@1: }
rlm@1: 
rlm@1: /* }====================================================== */
rlm@1: 
rlm@1: 
rlm@1: static int g_write (lua_State *L, FILE *f, int arg) {
rlm@1:   int nargs = lua_gettop(L) - 1;
rlm@1:   int status = 1;
rlm@1:   for (; nargs--; arg++) {
rlm@1:     if (lua_type(L, arg) == LUA_TNUMBER) {
rlm@1:       /* optimization: could be done exactly as for strings */
rlm@1:       status = status &&
rlm@1:           fprintf(f, LUA_NUMBER_FMT, lua_tonumber(L, arg)) > 0;
rlm@1:     }
rlm@1:     else {
rlm@1:       size_t l;
rlm@1:       const char *s = luaL_checklstring(L, arg, &l);
rlm@1:       status = status && (fwrite(s, sizeof(char), l, f) == l);
rlm@1:     }
rlm@1:   }
rlm@1:   return pushresult(L, status, NULL);
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int io_write (lua_State *L) {
rlm@1:   return g_write(L, getiofile(L, IO_OUTPUT), 1);
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int f_write (lua_State *L) {
rlm@1:   return g_write(L, tofile(L), 2);
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int f_seek (lua_State *L) {
rlm@1:   static const int mode[] = {SEEK_SET, SEEK_CUR, SEEK_END};
rlm@1:   static const char *const modenames[] = {"set", "cur", "end", NULL};
rlm@1:   FILE *f = tofile(L);
rlm@1:   int op = luaL_checkoption(L, 2, "cur", modenames);
rlm@1:   long offset = luaL_optlong(L, 3, 0);
rlm@1:   op = fseek(f, offset, mode[op]);
rlm@1:   if (op)
rlm@1:     return pushresult(L, 0, NULL);  /* error */
rlm@1:   else {
rlm@1:     lua_pushinteger(L, ftell(f));
rlm@1:     return 1;
rlm@1:   }
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int f_setvbuf (lua_State *L) {
rlm@1:   static const int mode[] = {_IONBF, _IOFBF, _IOLBF};
rlm@1:   static const char *const modenames[] = {"no", "full", "line", NULL};
rlm@1:   FILE *f = tofile(L);
rlm@1:   int op = luaL_checkoption(L, 2, NULL, modenames);
rlm@1:   lua_Integer sz = luaL_optinteger(L, 3, LUAL_BUFFERSIZE);
rlm@1:   int res = setvbuf(f, NULL, mode[op], sz);
rlm@1:   return pushresult(L, res == 0, NULL);
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: 
rlm@1: static int io_flush (lua_State *L) {
rlm@1:   return pushresult(L, fflush(getiofile(L, IO_OUTPUT)) == 0, NULL);
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static int f_flush (lua_State *L) {
rlm@1:   return pushresult(L, fflush(tofile(L)) == 0, NULL);
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static const luaL_Reg iolib[] = {
rlm@1:   {"close", io_close},
rlm@1:   {"flush", io_flush},
rlm@1:   {"input", io_input},
rlm@1:   {"lines", io_lines},
rlm@1:   {"open", io_open},
rlm@1:   {"output", io_output},
rlm@1:   {"popen", io_popen},
rlm@1:   {"read", io_read},
rlm@1:   {"tmpfile", io_tmpfile},
rlm@1:   {"type", io_type},
rlm@1:   {"write", io_write},
rlm@1:   {NULL, NULL}
rlm@1: };
rlm@1: 
rlm@1: 
rlm@1: static const luaL_Reg flib[] = {
rlm@1:   {"close", io_close},
rlm@1:   {"flush", f_flush},
rlm@1:   {"lines", f_lines},
rlm@1:   {"read", f_read},
rlm@1:   {"seek", f_seek},
rlm@1:   {"setvbuf", f_setvbuf},
rlm@1:   {"write", f_write},
rlm@1:   {"__gc", io_gc},
rlm@1:   {"__tostring", io_tostring},
rlm@1:   {NULL, NULL}
rlm@1: };
rlm@1: 
rlm@1: 
rlm@1: static void createmeta (lua_State *L) {
rlm@1:   luaL_newmetatable(L, LUA_FILEHANDLE);  /* create metatable for file handles */
rlm@1:   lua_pushvalue(L, -1);  /* push metatable */
rlm@1:   lua_setfield(L, -2, "__index");  /* metatable.__index = metatable */
rlm@1:   luaL_register(L, NULL, flib);  /* file methods */
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static void createstdfile (lua_State *L, FILE *f, int k, const char *fname) {
rlm@1:   *newfile(L) = f;
rlm@1:   if (k > 0) {
rlm@1:     lua_pushvalue(L, -1);
rlm@1:     lua_rawseti(L, LUA_ENVIRONINDEX, k);
rlm@1:   }
rlm@1:   lua_pushvalue(L, -2);  /* copy environment */
rlm@1:   lua_setfenv(L, -2);  /* set it */
rlm@1:   lua_setfield(L, -3, fname);
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: static void newfenv (lua_State *L, lua_CFunction cls) {
rlm@1:   lua_createtable(L, 0, 1);
rlm@1:   lua_pushcfunction(L, cls);
rlm@1:   lua_setfield(L, -2, "__close");
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: LUALIB_API int luaopen_io (lua_State *L) {
rlm@1:   createmeta(L);
rlm@1:   /* create (private) environment (with fields IO_INPUT, IO_OUTPUT, __close) */
rlm@1:   newfenv(L, io_fclose);
rlm@1:   lua_replace(L, LUA_ENVIRONINDEX);
rlm@1:   /* open library */
rlm@1:   luaL_register(L, LUA_IOLIBNAME, iolib);
rlm@1:   /* create (and set) default files */
rlm@1:   newfenv(L, io_noclose);  /* close function for default files */
rlm@1:   createstdfile(L, stdin, IO_INPUT, "stdin");
rlm@1:   createstdfile(L, stdout, IO_OUTPUT, "stdout");
rlm@1:   createstdfile(L, stderr, 0, "stderr");
rlm@1:   lua_pop(L, 1);  /* pop environment for default files */
rlm@1:   lua_getfield(L, -1, "popen");
rlm@1:   newfenv(L, io_pclose);  /* create environment for 'popen' */
rlm@1:   lua_setfenv(L, -2);  /* set fenv for 'popen' */
rlm@1:   lua_pop(L, 1);  /* pop 'popen' */
rlm@1:   return 1;
rlm@1: }
rlm@1: