fix idiom for setting stdio stream orientation to wide

the old idiom, f->mode |= f->mode+1, was adapted from the idiom for
setting byte orientation, f->mode |= f->mode-1, but the adaptation was
incorrect. unless the stream was alreasdy set byte-oriented, this code
incremented f->mode each time it was executed, which would eventually
lead to overflow. it could be fixed by changing it to f->mode |= 1,
but upcoming changes will require slightly more work at the time of
wide orientation, so it makes sense to just call fwide. as an
optimization in the single-character functions, fwide is only called
if the stream is not already wide-oriented.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/stdio/fputwc.c b/src/stdio/fputwc.c
index 7b621dd2..1bf165bf 100644
--- a/src/stdio/fputwc.c
+++ b/src/stdio/fputwc.c
@@ -8,7 +8,7 @@ wint_t __fputwc_unlocked(wchar_t c, FILE *f)
 	char mbc[MB_LEN_MAX];
 	int l;
 
-	f->mode |= f->mode+1;
+	if (f->mode <= 0) fwide(f, 1);
 
 	if (isascii(c)) {
 		c = putc_unlocked(c, f);