* io.c (io_reopen, rb_io_reopen): prohibit to change access mode for

special IO ports.  [ruby-dev:25225]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@7649 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,8 @@
+Fri Dec 24 02:52:52 2004  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* io.c (io_reopen, rb_io_reopen): prohibit to change access mode for
+	  special IO ports.  [ruby-dev:25225]
+
 Fri Dec 24 02:22:53 2004  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* ext/syck/rubyext.c (syck_loader_transfer): check type conversion.

io.c

@@ -1920,6 +1920,10 @@ rb_io_isatty(io)
     return Qtrue;
 }
 
+#define FMODE_PREP (1<<16)
+#define IS_PREP_STDIO(f) ((f)->mode & FMODE_PREP)
+#define PREP_STDIO_NAME(f) ((f)->path)
+
 static void
 fptr_finalize(fptr, noraise)
     OpenFile *fptr;
@@ -1928,9 +1932,7 @@ fptr_finalize(fptr, noraise)
     if (fptr->wbuf_len) {
         io_fflush(fptr);
     }
-    if (fptr->stdio_file == stdin ||
+    if (IS_PREP_STDIO(fptr) ||
-        fptr->stdio_file == stdout ||
-        fptr->stdio_file == stderr ||
         fptr->fd <= 2) {
 	return;
     }
@@ -3280,6 +3282,16 @@ io_reopen(io, nfile)
     GetOpenFile(nfile, orig);
 
     if (fptr == orig) return io;
+#if !defined __CYGWIN__
+    if (IS_PREP_STDIO(fptr)) {
+	if ((fptr->mode & FMODE_READWRITE) != (orig->mode & FMODE_READWRITE)) {
+	    rb_raise(rb_eArgError,
+		     "%s cannot change access mode from \"%s\" to \"%s\"",
+		     PREP_STDIO_NAME(fptr), rb_io_flags_mode(fptr->mode),
+		     rb_io_flags_mode(orig->mode));
+	}
+    }
+#endif
     if (orig->mode & FMODE_READABLE) {
 	pos = io_tell(orig);
     }
@@ -3303,9 +3315,7 @@ io_reopen(io, nfile)
     fd2 = orig->fd;
     if (fd != fd2) {
 #if !defined __CYGWIN__
-	if (fptr->stdio_file == stdin ||
+	if (IS_PREP_STDIO(fptr)) {
-            fptr->stdio_file == stdout ||
-            fptr->stdio_file == stderr) {
 	    /* need to keep stdio objects */
 	    if (dup2(fd2, fd) < 0)
 		rb_sys_fail(orig->path);
@@ -3386,7 +3396,15 @@ rb_io_reopen(argc, argv, file)
     }
 
     if (!NIL_P(nmode)) {
-	fptr->mode = rb_io_mode_flags(StringValuePtr(nmode));
+	int flags = rb_io_mode_flags(StringValuePtr(nmode));
+	if (IS_PREP_STDIO(fptr) &&
+	    (fptr->mode & FMODE_READWRITE) != (flags & FMODE_READWRITE)) {
+	    rb_raise(rb_eArgError,
+		     "%s cannot change access mode from \"%s\" to \"%s\"",
+		     PREP_STDIO_NAME(fptr), rb_io_flags_mode(fptr->mode),
+		     rb_io_flags_mode(flags));
+	}
+	fptr->mode = flags;
     }
 
     if (fptr->path) {
@@ -3866,10 +3884,11 @@ deferr_setter(val, id, variable)
 }
 
 static VALUE
-prep_stdio(f, mode, klass)
+prep_stdio(f, mode, klass, path)
     FILE *f;
     int mode;
     VALUE klass;
+    const char *path;
 {
     OpenFile *fp;
     VALUE io = io_alloc(klass);
@@ -3883,29 +3902,18 @@ prep_stdio(f, mode, klass)
     }
 #endif
     fp->stdio_file = f;
-    fp->mode = mode;
+    fp->mode = mode | FMODE_PREP;
     if (fp->mode & FMODE_WRITABLE) {
         if (fp->fd == 2) { /* stderr must be unbuffered */
             fp->mode |= FMODE_SYNC;
         }
         io_check_tty(fp);
     }
+    fp->path = strdup(path);
 
     return io;
 }
 
-static void
-prep_path(io, path)
-    VALUE io;
-    char *path;
-{
-    OpenFile *fptr;
-
-    GetOpenFile(io, fptr);
-    if (fptr->path) rb_bug("illegal prep_path() call");
-    fptr->path = strdup(path);
-}
-
 FILE *rb_io_stdio_file(OpenFile *fptr)
 {
     if (!fptr->stdio_file) {
@@ -4219,12 +4227,10 @@ next_argv()
 			fchown(fileno(fw), st.st_uid, st.st_gid);
 		    }
 #endif
-		    rb_stdout = prep_stdio(fw, FMODE_WRITABLE, rb_cFile);
+		    rb_stdout = prep_stdio(fw, FMODE_WRITABLE, rb_cFile, fn);
-		    prep_path(rb_stdout, fn);
 		    if (stdout_binmode) rb_io_binmode(rb_stdout);
 		}
-		current_file = prep_stdio(fr, FMODE_READABLE, rb_cFile);
+		current_file = prep_stdio(fr, FMODE_READABLE, rb_cFile, fn);
-		prep_path(current_file, fn);
 	    }
 	    if (binmode) rb_io_binmode(current_file);
 	}
@@ -5558,11 +5564,11 @@ Init_IO()
     rb_define_method(rb_cIO, "pid", rb_io_pid, 0);
     rb_define_method(rb_cIO, "inspect",  rb_io_inspect, 0);
 
-    rb_stdin = prep_stdio(stdin, FMODE_READABLE, rb_cIO);
+    rb_stdin = prep_stdio(stdin, FMODE_READABLE, rb_cIO, "<STDIN>");
     rb_define_variable("$stdin", &rb_stdin);
-    rb_stdout = prep_stdio(stdout, FMODE_WRITABLE, rb_cIO);
+    rb_stdout = prep_stdio(stdout, FMODE_WRITABLE, rb_cIO, "<STDOUT>");
     rb_define_hooked_variable("$stdout", &rb_stdout, 0, stdout_setter);
-    rb_stderr = prep_stdio(stderr, FMODE_WRITABLE, rb_cIO);
+    rb_stderr = prep_stdio(stderr, FMODE_WRITABLE, rb_cIO, "<STDERR>");
     rb_define_hooked_variable("$stderr", &rb_stderr, 0, stdout_setter);
     rb_define_hooked_variable("$>", &rb_stdout, 0, stdout_setter);
     orig_stdout = rb_stdout;