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-rw-r--r--src/liolib.c129
1 files changed, 82 insertions, 47 deletions
diff --git a/src/liolib.c b/src/liolib.c
index 64fa43b4..c453cb95 100644
--- a/src/liolib.c
+++ b/src/liolib.c
@@ -1,5 +1,5 @@
/*
-** $Id: liolib.c,v 2.85 2009/12/17 16:20:01 roberto Exp $
+** $Id: liolib.c,v 2.88 2010/03/26 20:58:11 roberto Exp $
** Standard I/O (and system) library
** See Copyright Notice in lua.h
*/
@@ -103,13 +103,12 @@ static FILE *tofile (lua_State *L) {
}
-
/*
** 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) {
+static FILE **newprefile (lua_State *L) {
FILE **pf = (FILE **)lua_newuserdata(L, sizeof(FILE *));
*pf = NULL; /* file handle is currently `closed' */
luaL_getmetatable(L, LUA_FILEHANDLE);
@@ -118,6 +117,14 @@ static FILE **newfile (lua_State *L) {
}
+static FILE **newfile (lua_State *L) {
+ FILE **pf = newprefile(L);
+ lua_pushvalue(L, lua_upvalueindex(1)); /* set upvalue... */
+ lua_setenv(L, -2); /* ... as environment for new file */
+ return pf;
+}
+
+
/*
** function to (not) close the standard files stdin, stdout, and stderr
*/
@@ -156,7 +163,7 @@ static int io_fclose (lua_State *L) {
static int aux_close (lua_State *L) {
- lua_getfenv(L, 1);
+ lua_getenv(L, 1);
lua_getfield(L, -1, "__close");
return (lua_tocfunction(L, -1))(L);
}
@@ -164,7 +171,7 @@ static int aux_close (lua_State *L) {
static int io_close (lua_State *L) {
if (lua_isnone(L, 1))
- lua_rawgeti(L, LUA_ENVIRONINDEX, IO_OUTPUT);
+ lua_rawgeti(L, lua_upvalueindex(1), IO_OUTPUT);
tofile(L); /* make sure argument is a file */
return aux_close(L);
}
@@ -229,7 +236,7 @@ static int io_tmpfile (lua_State *L) {
static FILE *getiofile (lua_State *L, int findex) {
FILE *f;
- lua_rawgeti(L, LUA_ENVIRONINDEX, findex);
+ lua_rawgeti(L, lua_upvalueindex(1), findex);
f = *(FILE **)lua_touserdata(L, -1);
if (f == NULL)
luaL_error(L, "standard %s file is closed", fnames[findex - 1]);
@@ -250,10 +257,10 @@ static int g_iofile (lua_State *L, int f, const char *mode) {
tofile(L); /* check that it's a valid file handle */
lua_pushvalue(L, 1);
}
- lua_rawseti(L, LUA_ENVIRONINDEX, f);
+ lua_rawseti(L, lua_upvalueindex(1), f);
}
/* return current value */
- lua_rawgeti(L, LUA_ENVIRONINDEX, f);
+ lua_rawgeti(L, lua_upvalueindex(1), f);
return 1;
}
@@ -271,35 +278,46 @@ 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_rawgeti(L, lua_upvalueindex(1), 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;
+ lua_replace(L, 1); /* put file at index 1 */
+ toclose = 1; /* close it after iteration */
}
+ aux_lines(L, toclose);
+ return 1;
}
@@ -316,7 +334,10 @@ 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 */
+ }
}
@@ -328,7 +349,7 @@ 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 (;;) {
@@ -342,7 +363,7 @@ static int read_line (lua_State *L, FILE *f) {
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' */
}
@@ -375,7 +396,7 @@ 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 */
@@ -394,7 +415,10 @@ 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 */
@@ -428,15 +452,22 @@ static int f_read (lua_State *L) {
static int io_readline (lua_State *L) {
FILE *f = *(FILE **)lua_touserdata(L, lua_upvalueindex(1));
- int success;
+ int i;
+ int n = lua_tointeger(L, lua_upvalueindex(2));
if (f == NULL) /* file is already closed? */
luaL_error(L, "file is already closed");
- success = read_line(L, f);
- if (ferror(f))
- return luaL_error(L, "%s", strerror(errno));
- if (success) return 1;
- else { /* EOF */
- if (lua_toboolean(L, lua_upvalueindex(2))) { /* generator created file? */
+ 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, 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 (!lua_isnil(L, -1)) /* is there error information? */
+ return luaL_error(L, "%s", lua_tostring(L, -1)); /* error */
+ /* else EOF */
+ 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 */
@@ -552,23 +583,27 @@ 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_register(L, NULL, flib); /* 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;
+ *newprefile(L) = f;
if (k > 0) {
- lua_pushvalue(L, -1);
- lua_rawseti(L, LUA_ENVIRONINDEX, k);
+ lua_pushvalue(L, -1); /* copy new file */
+ lua_rawseti(L, 1, k); /* add it to common upvalue */
}
- lua_pushvalue(L, -2); /* copy environment */
- lua_setfenv(L, -2); /* set it */
- lua_setfield(L, -3, fname);
+ lua_pushvalue(L, 3); /* get environment for default files */
+ lua_setenv(L, -2); /* set it as environment for file */
+ lua_setfield(L, 2, fname); /* add file to module */
}
-static void newfenv (lua_State *L, lua_CFunction cls) {
+/*
+** pushes a new table with {__close = cls}
+*/
+static void newenv (lua_State *L, lua_CFunction cls) {
lua_createtable(L, 0, 1);
lua_pushcfunction(L, cls);
lua_setfield(L, -2, "__close");
@@ -576,21 +611,21 @@ static void newfenv (lua_State *L, lua_CFunction cls) {
LUAMOD_API int luaopen_io (lua_State *L) {
+ lua_settop(L, 0);
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);
+ newenv(L, io_fclose); /* upvalue for all io functions at index 1 */
+ lua_pushvalue(L, -1); /* copy to be consumed by 'openlib' */
+ luaL_openlib(L, LUA_IOLIBNAME, iolib, 1); /* new module at index 2 */
/* create (and set) default files */
- newfenv(L, io_noclose); /* close function for default files */
+ newenv(L, io_noclose); /* environment for default files at index 3 */
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_getfield(L, 2, "popen");
+ newenv(L, io_pclose); /* create environment for 'popen' streams */
+ lua_setupvalue(L, -2, 1); /* set it as upvalue for 'popen' */
lua_pop(L, 1); /* pop 'popen' */
return 1;
}
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