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-rw-r--r--lua/liolib.c496
1 files changed, 300 insertions, 196 deletions
diff --git a/lua/liolib.c b/lua/liolib.c
index e79ed1c..4814aa2 100644
--- a/lua/liolib.c
+++ b/lua/liolib.c
@@ -1,10 +1,20 @@
/*
-** $Id: liolib.c,v 2.73.1.3 2008/01/18 17:47:43 roberto Exp $
+** $Id: liolib.c,v 2.108 2011/11/25 12:50:03 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>
@@ -20,48 +30,95 @@
-#define IO_INPUT 1
-#define IO_OUTPUT 2
+/*
+** {======================================================
+** lua_popen spawns a new process connected to the current
+** one through the file streams.
+** =======================================================
+*/
+
+#if !defined(lua_popen) /* { */
+#if defined(LUA_USE_POPEN) /* { */
-static const char *const fnames[] = {"input", "output"};
+#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) /* }{ */
-static int pushresult (lua_State *L, int i, const char *filename) {
- int en = errno; /* calls to Lua API may change this value */
- if (i) {
- lua_pushboolean(L, 1);
- return 1;
- }
- else {
- lua_pushnil(L);
- if (filename)
- lua_pushfstring(L, "%s: %s", filename, strerror(en));
- else
- lua_pushfstring(L, "%s", strerror(en));
- lua_pushinteger(L, en);
- return 3;
- }
-}
+#define lua_popen(L,c,m) ((void)L, _popen(c,m))
+#define lua_pclose(L,file) ((void)L, _pclose(file))
-static void fileerror (lua_State *L, int arg, const char *filename) {
- lua_pushfstring(L, "%s: %s", filename, strerror(errno));
- luaL_argerror(L, arg, lua_tostring(L, -1));
-}
+#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
-#define tofilep(L) ((FILE **)luaL_checkudata(L, 1, LUA_FILEHANDLE))
+#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) {
- void *ud;
+ LStream *p;
luaL_checkany(L, 1);
- ud = lua_touserdata(L, 1);
- lua_getfield(L, LUA_REGISTRYINDEX, LUA_FILEHANDLE);
- if (ud == NULL || !lua_getmetatable(L, 1) || !lua_rawequal(L, -2, -1))
+ p = (LStream *)luaL_testudata(L, 1, LUA_FILEHANDLE);
+ if (p == NULL)
lua_pushnil(L); /* not a file */
- else if (*((FILE **)ud) == NULL)
+ else if (isclosed(p))
lua_pushliteral(L, "closed file");
else
lua_pushliteral(L, "file");
@@ -69,47 +126,59 @@ static int io_type (lua_State *L) {
}
+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) {
- FILE **f = tofilep(L);
- if (*f == NULL)
+ LStream *p = tolstream(L);
+ if (isclosed(p))
luaL_error(L, "attempt to use a closed file");
- return *f;
+ 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 FILE **newfile (lua_State *L) {
- FILE **pf = (FILE **)lua_newuserdata(L, sizeof(FILE *));
- *pf = NULL; /* file handle is currently `closed' */
- luaL_getmetatable(L, LUA_FILEHANDLE);
- lua_setmetatable(L, -2);
- return pf;
+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;
}
-/*
-** function to (not) close the standard files stdin, stdout, and stderr
-*/
-static int io_noclose (lua_State *L) {
- lua_pushnil(L);
- lua_pushliteral(L, "cannot close standard file");
- return 2;
+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 */
}
-/*
-** function to close 'popen' files
-*/
-static int io_pclose (lua_State *L) {
- FILE **p = tofilep(L);
- int ok = lua_pclose(L, *p);
- *p = NULL;
- return pushresult(L, ok, NULL);
+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;
}
@@ -117,103 +186,94 @@ static int io_pclose (lua_State *L) {
** function to close regular files
*/
static int io_fclose (lua_State *L) {
- FILE **p = tofilep(L);
- int ok = (fclose(*p) == 0);
- *p = NULL;
- return pushresult(L, ok, NULL);
-}
-
-
-static int aux_close (lua_State *L) {
- lua_getfenv(L, 1);
- lua_getfield(L, -1, "__close");
- return (lua_tocfunction(L, -1))(L);
-}
-
-
-static int io_close (lua_State *L) {
- if (lua_isnone(L, 1))
- lua_rawgeti(L, LUA_ENVIRONINDEX, IO_OUTPUT);
- tofile(L); /* make sure argument is a file */
- return aux_close(L);
+ LStream *p = tolstream(L);
+ int res = fclose(p->f);
+ return luaL_fileresult(L, (res == 0), NULL);
}
-static int io_gc (lua_State *L) {
- FILE *f = *tofilep(L);
- /* ignore closed files */
- if (f != NULL)
- aux_close(L);
- return 0;
+static LStream *newfile (lua_State *L) {
+ LStream *p = newprefile(L);
+ p->f = NULL;
+ p->closef = &io_fclose;
+ return p;
}
-static int io_tostring (lua_State *L) {
- FILE *f = *tofilep(L);
- if (f == NULL)
- lua_pushliteral(L, "file (closed)");
- else
- lua_pushfstring(L, "file (%p)", f);
- return 1;
+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");
- FILE **pf = newfile(L);
- *pf = fopen(filename, mode);
- return (*pf == NULL) ? pushresult(L, 0, filename) : 1;
+ LStream *p = newfile(L);
+ int i = 0;
+ /* check whether 'mode' matches '[rwa]%+?b?' */
+ if (!(mode[i] != '\0' && strchr("rwa", mode[i++]) != NULL &&
+ (mode[i] != '+' || ++i) && /* skip if char is '+' */
+ (mode[i] != 'b' || ++i) && /* skip if char is 'b' */
+ (mode[i] == '\0')))
+ return luaL_error(L, "invalid mode " LUA_QS
+ " (should match " LUA_QL("[rwa]%%+?b?") ")", mode);
+ p->f = fopen(filename, mode);
+ return (p->f == NULL) ? luaL_fileresult(L, 0, filename) : 1;
}
/*
-** this function has a separated environment, which defines the
-** correct __close for 'popen' files
+** 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");
- FILE **pf = newfile(L);
- *pf = lua_popen(L, filename, mode);
- return (*pf == NULL) ? pushresult(L, 0, filename) : 1;
+ 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) {
- FILE **pf = newfile(L);
- *pf = tmpfile();
- return (*pf == NULL) ? pushresult(L, 0, NULL) : 1;
+ LStream *p = newfile(L);
+ p->f = tmpfile();
+ return (p->f == NULL) ? luaL_fileresult(L, 0, NULL) : 1;
}
-static FILE *getiofile (lua_State *L, int findex) {
- FILE *f;
- lua_rawgeti(L, LUA_ENVIRONINDEX, findex);
- f = *(FILE **)lua_touserdata(L, -1);
- if (f == NULL)
- luaL_error(L, "standard %s file is closed", fnames[findex - 1]);
- return f;
+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, int f, const char *mode) {
+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) {
- FILE **pf = newfile(L);
- *pf = fopen(filename, mode);
- if (*pf == NULL)
- fileerror(L, 1, filename);
- }
+ if (filename)
+ opencheck(L, filename, mode);
else {
tofile(L); /* check that it's a valid file handle */
lua_pushvalue(L, 1);
}
- lua_rawseti(L, LUA_ENVIRONINDEX, f);
+ lua_setfield(L, LUA_REGISTRYINDEX, f);
}
/* return current value */
- lua_rawgeti(L, LUA_ENVIRONINDEX, f);
+ lua_getfield(L, LUA_REGISTRYINDEX, f);
return 1;
}
@@ -231,35 +291,43 @@ static int io_output (lua_State *L) {
static int io_readline (lua_State *L);
-static void aux_lines (lua_State *L, int idx, int toclose) {
- lua_pushvalue(L, idx);
+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 */
- lua_pushcclosure(L, io_readline, 2);
+ 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, 1, 0);
+ aux_lines(L, 0);
return 1;
}
static int io_lines (lua_State *L) {
- if (lua_isnoneornil(L, 1)) { /* no arguments? */
- /* will iterate over default input */
- lua_rawgeti(L, LUA_ENVIRONINDEX, IO_INPUT);
- return f_lines(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 {
+ else { /* open a new file */
const char *filename = luaL_checkstring(L, 1);
- FILE **pf = newfile(L);
- *pf = fopen(filename, "r");
- if (*pf == NULL)
- fileerror(L, 1, filename);
- aux_lines(L, lua_gettop(L), 1);
- return 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;
}
@@ -276,7 +344,10 @@ static int read_number (lua_State *L, FILE *f) {
lua_pushnumber(L, d);
return 1;
}
- else return 0; /* read fails */
+ else {
+ lua_pushnil(L); /* "result" to be removed */
+ return 0; /* read fails */
+ }
}
@@ -288,7 +359,7 @@ static int test_eof (lua_State *L, FILE *f) {
}
-static int read_line (lua_State *L, FILE *f) {
+static int read_line (lua_State *L, FILE *f, int chop) {
luaL_Buffer b;
luaL_buffinit(L, &b);
for (;;) {
@@ -296,13 +367,13 @@ static int read_line (lua_State *L, FILE *f) {
char *p = luaL_prepbuffer(&b);
if (fgets(p, LUAL_BUFFERSIZE, f) == NULL) { /* eof? */
luaL_pushresult(&b); /* close buffer */
- return (lua_objlen(L, -1) > 0); /* check whether read something */
+ 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 - 1); /* do not include `eol' */
+ luaL_addsize(&b, l - chop); /* chop 'eol' if needed */
luaL_pushresult(&b); /* close buffer */
return 1; /* read at least an `eol' */
}
@@ -310,21 +381,34 @@ static int read_line (lua_State *L, FILE *f) {
}
+#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 rlen; /* how much to read */
size_t nr; /* number of chars actually read */
+ char *p;
luaL_Buffer b;
luaL_buffinit(L, &b);
- rlen = LUAL_BUFFERSIZE; /* try to read that much each time */
- do {
- char *p = luaL_prepbuffer(&b);
- if (rlen > n) rlen = n; /* cannot read more than asked */
- nr = fread(p, sizeof(char), rlen, f);
- luaL_addsize(&b, nr);
- n -= nr; /* still have to read `n' chars */
- } while (n > 0 && nr == rlen); /* until end of count or eof */
+ 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 (n == 0 || lua_objlen(L, -1) > 0);
+ return (nr > 0); /* true iff read something */
}
@@ -334,7 +418,7 @@ static int g_read (lua_State *L, FILE *f, int first) {
int n;
clearerr(f);
if (nargs == 0) { /* no arguments? */
- success = read_line(L, f);
+ 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 */
@@ -353,10 +437,13 @@ static int g_read (lua_State *L, FILE *f, int first) {
success = read_number(L, f);
break;
case 'l': /* line */
- success = read_line(L, f);
+ 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_chars(L, f, ~((size_t)0)); /* read MAX_SIZE_T chars */
+ read_all(L, f); /* read entire file */
success = 1; /* always success */
break;
default:
@@ -366,7 +453,7 @@ static int g_read (lua_State *L, FILE *f, int first) {
}
}
if (ferror(f))
- return pushresult(L, 0, NULL);
+ return luaL_fileresult(L, 0, NULL);
if (!success) {
lua_pop(L, 1); /* remove last result */
lua_pushnil(L); /* push nil instead */
@@ -386,16 +473,24 @@ static int f_read (lua_State *L) {
static int io_readline (lua_State *L) {
- FILE *f = *(FILE **)lua_touserdata(L, lua_upvalueindex(1));
- int sucess;
- if (f == NULL) /* file is already closed? */
- luaL_error(L, "file is already closed");
- sucess = read_line(L, f);
- if (ferror(f))
- return luaL_error(L, "%s", strerror(errno));
- if (sucess) return 1;
- else { /* EOF */
- if (lua_toboolean(L, lua_upvalueindex(2))) { /* generator created file? */
+ 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 */
@@ -408,7 +503,7 @@ static int io_readline (lua_State *L) {
static int g_write (lua_State *L, FILE *f, int arg) {
- int nargs = lua_gettop(L) - 1;
+ int nargs = lua_gettop(L) - arg;
int status = 1;
for (; nargs--; arg++) {
if (lua_type(L, arg) == LUA_TNUMBER) {
@@ -422,7 +517,8 @@ static int g_write (lua_State *L, FILE *f, int arg) {
status = status && (fwrite(s, sizeof(char), l, f) == l);
}
}
- return pushresult(L, status, NULL);
+ if (status) return 1; /* file handle already on stack top */
+ else return luaL_fileresult(L, status, NULL);
}
@@ -432,7 +528,9 @@ static int io_write (lua_State *L) {
static int f_write (lua_State *L) {
- return g_write(L, tofile(L), 2);
+ FILE *f = tofile(L);
+ lua_pushvalue(L, 1); /* push file at the stack top (to be returned) */
+ return g_write(L, f, 2);
}
@@ -441,12 +539,15 @@ static int f_seek (lua_State *L) {
static const char *const modenames[] = {"set", "cur", "end", NULL};
FILE *f = tofile(L);
int op = luaL_checkoption(L, 2, "cur", modenames);
- long offset = luaL_optlong(L, 3, 0);
- op = fseek(f, offset, mode[op]);
+ 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 pushresult(L, 0, NULL); /* error */
+ return luaL_fileresult(L, 0, NULL); /* error */
else {
- lua_pushinteger(L, ftell(f));
+ lua_pushnumber(L, (lua_Number)l_ftell(f));
return 1;
}
}
@@ -459,21 +560,24 @@ static int f_setvbuf (lua_State *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 pushresult(L, res == 0, NULL);
+ return luaL_fileresult(L, res == 0, NULL);
}
static int io_flush (lua_State *L) {
- return pushresult(L, fflush(getiofile(L, IO_OUTPUT)) == 0, NULL);
+ return luaL_fileresult(L, fflush(getiofile(L, IO_OUTPUT)) == 0, NULL);
}
static int f_flush (lua_State *L) {
- return pushresult(L, fflush(tofile(L)) == 0, NULL);
+ return luaL_fileresult(L, fflush(tofile(L)) == 0, NULL);
}
+/*
+** functions for 'io' library
+*/
static const luaL_Reg iolib[] = {
{"close", io_close},
{"flush", io_flush},
@@ -490,6 +594,9 @@ static const luaL_Reg iolib[] = {
};
+/*
+** methods for file handles
+*/
static const luaL_Reg flib[] = {
{"close", io_close},
{"flush", f_flush},
@@ -498,8 +605,8 @@ static const luaL_Reg flib[] = {
{"seek", f_seek},
{"setvbuf", f_setvbuf},
{"write", f_write},
- {"__gc", io_gc},
- {"__tostring", io_tostring},
+ {"__gc", f_gc},
+ {"__tostring", f_tostring},
{NULL, NULL}
};
@@ -508,46 +615,43 @@ 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_register(L, NULL, flib); /* file methods */
+ luaL_setfuncs(L, flib, 0); /* add file methods to new metatable */
+ lua_pop(L, 1); /* pop new metatable */
}
-static void createstdfile (lua_State *L, FILE *f, int k, const char *fname) {
- *newfile(L) = f;
- if (k > 0) {
- lua_pushvalue(L, -1);
- lua_rawseti(L, LUA_ENVIRONINDEX, k);
- }
- lua_pushvalue(L, -2); /* copy environment */
- lua_setfenv(L, -2); /* set it */
- lua_setfield(L, -3, fname);
+/*
+** 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 newfenv (lua_State *L, lua_CFunction cls) {
- lua_createtable(L, 0, 1);
- lua_pushcfunction(L, cls);
- lua_setfield(L, -2, "__close");
+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 */
}
-LUALIB_API int luaopen_io (lua_State *L) {
+LUAMOD_API int luaopen_io (lua_State *L) {
+ luaL_newlib(L, iolib); /* new module */
createmeta(L);
- /* create (private) environment (with fields IO_INPUT, IO_OUTPUT, __close) */
- newfenv(L, io_fclose);
- lua_replace(L, LUA_ENVIRONINDEX);
- /* open library */
- luaL_register(L, LUA_IOLIBNAME, iolib);
/* create (and set) default files */
- newfenv(L, io_noclose); /* close function for default files */
createstdfile(L, stdin, IO_INPUT, "stdin");
createstdfile(L, stdout, IO_OUTPUT, "stdout");
- createstdfile(L, stderr, 0, "stderr");
- lua_pop(L, 1); /* pop environment for default files */
- lua_getfield(L, -1, "popen");
- newfenv(L, io_pclose); /* create environment for 'popen' */
- lua_setfenv(L, -2); /* set fenv for 'popen' */
- lua_pop(L, 1); /* pop 'popen' */
+ createstdfile(L, stderr, NULL, "stderr");
return 1;
}