* io.c (io_reopen): avoid dup2() equal handles not to close itself and

  to get rid of a msvcrt bug.  [ruby-dev:20919]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_6@4177 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

2 files changed, 31 insertions, 22 deletions

diff --git a/ChangeLog b/ChangeLog
index 770e3bd9ed..fa63339d79 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sun Jul 27 03:10:31 2003  Nobuyoshi Nakada  <nobu.nokada@softhome.net>
+
+	* io.c (io_reopen): avoid dup2() equal handles not to close itself and
+	  to get rid of a msvcrt bug.  [ruby-dev:20919]
+
 Thu Jul 17 13:42:53 2003  WATANABE Hirofumi  <eban@ruby-lang.org>
 
 	* lib/ftools.rb (File::makedirs): do not handle "//" as a directory.
diff --git a/io.c b/io.c
index 6fad35c73c..8d6796795c 100644
--- a/io.c
+++ b/io.c
@@ -1845,7 +1845,7 @@ io_reopen(io, nfile)
 {
     OpenFile *fptr, *orig;
     char *mode;
-    int fd;
+    int fd, fd2;
     long pos;
 
     nfile = rb_io_get_io(nfile);
@@ -1878,34 +1878,38 @@ io_reopen(io, nfile)
 
     mode = rb_io_mode_string(fptr);
     fd = fileno(fptr->f);
-    if (fd < 3) {
-	clearerr(fptr->f);
-	/* need to keep stdio objects */
-	if (dup2(fileno(orig->f), fd) < 0)
-	    rb_sys_fail(orig->path);
-    }
-    else {
-	fclose(fptr->f);
-	if (dup2(fileno(orig->f), fd) < 0)
-	    rb_sys_fail(orig->path);
-	fptr->f = rb_fdopen(fd, mode);
-    }
-    if ((orig->mode & FMODE_READABLE) && pos >= 0) {
-	io_seek(fptr, pos, SEEK_SET);
-	io_seek(orig, pos, SEEK_SET);
+    fd2 = fileno(orig->f);
+    if (fd != fd2) {
+	if (fd < 3) {
+	    clearerr(fptr->f);
+	    /* need to keep stdio objects */
+	    if (dup2(fd2, fd) < 0)
+		rb_sys_fail(orig->path);
+	}
+	else {
+	    fclose(fptr->f);
+	    if (dup2(fd2, fd) < 0)
+		rb_sys_fail(orig->path);
+	    fptr->f = rb_fdopen(fd, mode);
+	}
+	if ((orig->mode & FMODE_READABLE) && pos >= 0) {
+	    io_seek(fptr, pos, SEEK_SET);
+	    io_seek(orig, pos, SEEK_SET);
+	}
     }
 
     if (fptr->f2) {
 	fd = fileno(fptr->f2);
-	fclose(fptr->f2);
-	if (orig->f2) {
-	    if (dup2(fileno(orig->f2), fd) < 0)
+	if (!orig->f2) {
+	    fclose(fptr->f2);
+	    fptr->f2 = 0;
+	}
+	else if (fd != (fd2 = fileno(orig->f2))) {
+	    fclose(fptr->f2);
+	    if (dup2(fd2, fd) < 0)
 		rb_sys_fail(orig->path);
 	    fptr->f2 = rb_fdopen(fd, "w");
 	}
-	else {
-	    fptr->f2 = 0;
-	}
     }
 
     if (fptr->mode & FMODE_BINMODE) {