MDEV-27142 disable text mode for Windows stdio by default

This avoids LF->CRLF conversion by the C runtime, which historically has
been rather buggy (see MDEV-9409)

Disabling text mode also fixes the  --binary-mode in command line client
to work the same on Windows, as it does elsewhere.

The user-visible effect is that some text files, e.g output of mysqldump
or mysqlbinlog will not have CRLF end-of-lines,but LF. That should be
acceptable, as even Notepad can read this Unix EOLs since 2018
(on older Windows, Wordpad can)

Leave error log in text(CRLF) mode for now, for the sake of old Windows.

1 files changed, 9 insertions, 10 deletions

diff --git a/mysys/my_init.c b/mysys/my_init.c
index 2f21bcb735f..44488e5848a 100644
--- a/mysys/my_init.c
+++ b/mysys/my_init.c
@@ -401,16 +401,15 @@ static void my_win_init(void)
 
   _tzset();
 
-  /*
-   We do not want text translation (LF->CRLF)
-   when stdout is console/terminal, it is buggy
-  */
-  if (fileno(stdout) >= 0 && isatty(fileno(stdout)))
-    (void)setmode(fileno(stdout), O_BINARY);
-
-  if (fileno(stderr) >= 0 && isatty(fileno(stderr)))
-    (void) setmode(fileno(stderr), O_BINARY);
-
+  /* Disable automatic LF->CRLF translation. */
+  FILE* stdf[]= {stdin, stdout, stderr};
+  for (int i= 0; i < array_elements(stdf); i++)
+  {
+    int fd= fileno(stdf[i]);
+    if (fd >= 0)
+      (void) _setmode(fd, O_BINARY);
+  }
+  _set_fmode(O_BINARY);
   setup_codepages();
   DBUG_VOID_RETURN;
 }