1 files changed, 50 insertions, 0 deletions
diff --git a/src/stdio/fflush.c b/src/stdio/fflush.c
new file mode 100644
index 00000000..cf3f5b0e
--- /dev/null
+++ b/src/stdio/fflush.c
@@ -0,0 +1,50 @@
+#include "stdio_impl.h"
+
+static int __fflush_unlocked(FILE *f)
+{
+	/* If writing, flush output. */
+	if (f->wpos > f->buf && __oflow(f)) return -1;
+
+	/* If reading, sync position, per POSIX */
+	if (f->rpos < f->rend) f->seek(f, f->rpos-f->rend, SEEK_CUR);
+	f->rpos = f->rend;
+
+	/* Hook for special behavior on flush */
+	if (f->flush) f->flush(f);
+
+	return (f->flags & F_ERR) ? EOF : 0;
+}
+
+/* stdout.c will override this if linked */
+static FILE *const __dummy = 0;
+weak_alias(__dummy, __stdout_to_flush);
+
+int fflush(FILE *f)
+{
+	int r;
+	FILE *next;
+
+	if (f) {
+		FLOCK(f);
+		r = __fflush_unlocked(f);
+		FUNLOCK(f);
+		return r;
+	}
+
+	r = __stdout_to_flush ? fflush(__stdout_to_flush) : 0;
+
+	OFLLOCK();
+	for (f=ofl_head; f; f=next) {
+		FLOCK(f);
+		OFLUNLOCK();
+		r |= __fflush_unlocked(f);
+		OFLLOCK();
+		next = f->next;
+		FUNLOCK(f);
+	}
+	OFLUNLOCK();
+	
+	return r;
+}
+
+weak_alias(__fflush_unlocked, fflush_unlocked);