diff options
| author | Thomas Bushnell <thomas@gnu.org> | 1997-02-25 21:28:37 +0000 |
|---|---|---|
| committer | Thomas Bushnell <thomas@gnu.org> | 1997-02-25 21:28:37 +0000 |
| commit | f07a4c844da9f0ecae5bbee1ab94be56505f26f7 (patch) | |
| tree | 12b07c7e578fc1a5f53dbfde2632408491ff2a70 /device/cirbuf.h | |
Initial source
Diffstat (limited to 'device/cirbuf.h')
| -rw-r--r-- | device/cirbuf.h | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/device/cirbuf.h b/device/cirbuf.h new file mode 100644 index 0000000..a3f50ce --- /dev/null +++ b/device/cirbuf.h @@ -0,0 +1,62 @@ +/* + * Mach Operating System + * Copyright (c) 1991,1990 Carnegie Mellon University + * All Rights Reserved. + * + * Permission to use, copy, modify and distribute this software and its + * documentation is hereby granted, provided that both the copyright + * notice and this permission notice appear in all copies of the + * software, derivative works or modified versions, and any portions + * thereof, and that both notices appear in supporting documentation. + * + * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" + * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR + * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. + * + * Carnegie Mellon requests users of this software to return to + * + * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU + * School of Computer Science + * Carnegie Mellon University + * Pittsburgh PA 15213-3890 + * + * any improvements or extensions that they make and grant Carnegie Mellon + * the rights to redistribute these changes. + */ +/* + * Author: David B. Golub, Carnegie Mellon University + * Date: 7/90 + */ + +#ifndef _DEVICE_CIRBUF_H_ +#define _DEVICE_CIRBUF_H_ + +/* + * Circular buffers for TTY + */ + +struct cirbuf { + char * c_start; /* start of buffer */ + char * c_end; /* end of buffer + 1*/ + char * c_cf; /* read pointer */ + char * c_cl; /* write pointer */ + short c_cc; /* current number of characters + (compatibility) */ + short c_hog; /* max ever */ +}; + +/* + * Exported routines + */ +extern int putc(int, struct cirbuf *); +extern int getc(struct cirbuf *); +extern int q_to_b(struct cirbuf *, char *, int); +extern int b_to_q(char *, int, struct cirbuf *); +extern int nqdb(struct cirbuf *, int); +extern void ndflush(struct cirbuf *, int); +extern void cb_clear(struct cirbuf *); + +extern void cb_alloc(struct cirbuf *, int); +extern void cb_free(struct cirbuf *); + +#endif /* _DEVICE_CIRBUF_H_ */ |