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-rw-r--r--libc/stdio/freopen.c66
1 files changed, 66 insertions, 0 deletions
diff --git a/libc/stdio/freopen.c b/libc/stdio/freopen.c
new file mode 100644
index 000000000..0eccaac1f
--- /dev/null
+++ b/libc/stdio/freopen.c
@@ -0,0 +1,66 @@
+/* Copyright (C) 2004 Manuel Novoa III <mjn3@codepoet.org>
+ *
+ * GNU Library General Public License (LGPL) version 2 or later.
+ *
+ * Dedicated to Toni. See uClibc/DEDICATION.mjn3 for details.
+ */
+
+#include "_stdio.h"
+
+#ifdef __DO_LARGEFILE
+# ifndef __UCLIBC_HAS_LFS__
+# error large file support is not enabled!
+# endif
+
+# define freopen freopen64
+# define FILEDES_ARG (-2)
+#else
+# define FILEDES_ARG (-1)
+#endif
+
+FILE *freopen(const char * __restrict filename, const char * __restrict mode,
+ register FILE * __restrict stream)
+{
+ /*
+ * ANSI/ISO allow (implementation-defined) change of mode for an
+ * existing file if filename is NULL. It doesn't look like Linux
+ * supports this, so we don't here.
+ *
+ * NOTE: Whether or not the stream is free'd on failure is unclear
+ * w.r.t. ANSI/ISO. This implementation chooses to NOT free
+ * the stream and associated buffer if they were dynamically
+ * allocated.
+ * NOTE: Previous versions of uClibc did free dynamic storage.
+ *
+ * TODO: Apparently linux allows setting append mode. Implement?
+ */
+ unsigned short dynmode;
+ register FILE *fp;
+ __STDIO_AUTO_THREADLOCK_VAR;
+
+ __STDIO_AUTO_THREADLOCK(stream);
+
+ __STDIO_STREAM_VALIDATE(stream);
+
+ /* First, flush and close, but don't deallocate, the stream. */
+ /* This also removes the stream for the open file list. */
+ dynmode = (stream->__modeflags & (__FLAG_FREEBUF|__FLAG_FREEFILE));
+
+ stream->__modeflags &= ~(__FLAG_FREEBUF|__FLAG_FREEFILE);
+
+ /* Only call fclose on the stream if it is not already closed. */
+ if ((stream->__modeflags & (__FLAG_READONLY|__FLAG_WRITEONLY))
+ != (__FLAG_READONLY|__FLAG_WRITEONLY)
+ ) {
+ fclose(stream); /* Failures are ignored. */
+ }
+
+ fp = _stdio_fopen(((intptr_t) filename), mode, stream, FILEDES_ARG);
+
+ /* Reset the allocation flags. */
+ stream->__modeflags |= dynmode;
+
+ __STDIO_AUTO_THREADUNLOCK(stream);
+
+ return fp;
+}