1 files changed, 95 insertions, 0 deletions
diff --git a/private/crt32/stdio/stream.c b/private/crt32/stdio/stream.c
new file mode 100644
index 000000000..96946a3cf
--- /dev/null
+++ b/private/crt32/stdio/stream.c
@@ -0,0 +1,95 @@
+/***
+*stream.c - find a stream not in use
+*
+*	Copyright (c) 1985-1992, Microsoft Corporation. All rights reserved.
+*
+*Purpose:
+*	defines _getstream() - find a stream not in use
+*
+*Revision History:
+*	09-02-83  RN	initial version
+*	11-01-87  JCR	Multi-thread support
+*	05-24-88  PHG	Merged DLL and normal versions
+*	06-10-88  JCR	Use near pointer to reference _iob[] entries
+*	08-17-89  GJF	Removed _NEAR_, fixed copyright and indenting.
+*	02-16-90  GJF	Fixed copyright
+*	03-19-90  GJF	Made calling type _CALLTYPE1, added #include
+*			<cruntime.h> and removed #include <register.h>.
+*	10-03-90  GJF	New-style function declarator.
+*	12-31-91  GJF	Improved multi-thread lock usage [_WIN32_].
+*
+*******************************************************************************/
+
+#include <cruntime.h>
+#include <stdio.h>
+#include <file2.h>
+#include <internal.h>
+#include <os2dll.h>
+
+/***
+*FILE *_getstream() - find a stream not in use
+*
+*Purpose:
+*	find a stream not in use and make it available to caller. _lastiob is
+*	the last FILE address. intended for use inside library only
+*
+*Entry:
+*	None.  Reads _iob.
+*
+*Exit:
+*	returns a pointer to a free stream, or NULL if all are in use.	A
+*	stream becomes allocated if the caller decided to use it by setting
+*	any r, w, r/w mode.
+*
+*	Note:  Optimized the code to use a near pointer for the stream.  This
+*	is especially helpful in large model.  However, the drawback is that we
+*	need another temporary 'retval' so that when we return NULL, we return
+*	0:0, not DS:0.
+*
+*	[Multi-thread note: If a free stream is found, it is returned in a
+*	LOCKED state.  It is the caller's responsibility to unlock the stream.]
+*
+*Exceptions:
+*
+*******************************************************************************/
+
+FILE * _CALLTYPE1 _getstream (
+	void
+	)
+{
+	REG1 FILE *stream = _iob;
+	REG2 FILE *retval = NULL;
+#ifdef MTHREAD
+	int index;
+#endif
+
+	/* Get the iob[] scan lock */
+	_mlock(_IOB_SCAN_LOCK);
+
+	/* Loop through the _iob table looking for a free stream.*/
+	for (; stream <= _lastiob; stream++) {
+
+		if ( !inuse(stream) ) {
+#ifdef MTHREAD
+			index = _iob_index(stream);
+			_lock_str(index);
+
+			/* make sure the _iob entry is still free */
+			if ( inuse(stream) ) {
+				/* no longer free! release the lock and
+				   continue looping */
+				_unlock_str(index);
+				continue;
+			}
+#endif
+			stream->_flag = stream->_cnt = 0;
+			stream->_ptr = stream->_base = NULL;
+			stream->_file = -1;
+			retval = stream;
+			break;
+		}
+	}
+
+	_munlock(_IOB_SCAN_LOCK);
+	return(retval);
+}