change stdio_ext __freading/__fwriting semantics slightly

the old behavior was to only consider a stream to be "reading" or
"writing" if it had buffered, unread/unwritten data. this reportedly
differs from the traditional behavior of these functions, which is
essentially to return true as much as possible without creating the
possibility that both __freading and __fwriting could return true.

gnulib expects __fwriting to return true as soon as a file is opened
write-only, and possibly expects other cases that depend on the
traditional behavior. and since these functions exist mostly for
gnulib (does anything else use them??), they should match the expected
behavior to avoid even more ugly hacks and workarounds...

diff --git a/src/stdio/ext.c b/src/stdio/ext.c
index 6b8ce91c5eb2a9fca45a8a9771ccea99452b5152..1fd9549019330f5944a83c4ac7a70c2bce93daab 100644 (file)
--- a/src/stdio/ext.c
+++ b/src/stdio/ext.c
@@ -14,12 +14,12 @@ int __fsetlocking(FILE *f, int type)
 
 int __fwriting(FILE *f)
 {
-       return f->wend && f->wpos > f->wbase;
+       return (f->flags & F_NORD) || f->wend;
 }
 
 int __freading(FILE *f)
 {
-       return f->rend > f->rpos;
+       return (f->flags & F_NOWR) || f->rend;
 }
 
 int __freadable(FILE *f)