factor code that discards data from abuf strucure into a single

abuf_rdiscard() routine. Similarly add abuf_wcommit() routine for
writing. The purpose is to stop manupulating FIFO pointers in
various places outiside abuf.c, its too error prone.
No behaviour change.

ok jakemsr

1 files changed, 22 insertions, 7 deletions

diff --git a/usr.bin/aucat/abuf.c b/usr.bin/aucat/abuf.c
index e79af1199f9..a3143d9ac18 100644
--- a/usr.bin/aucat/abuf.c
+++ b/usr.bin/aucat/abuf.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: abuf.c,v 1.2 2008/05/25 21:16:37 ratchov Exp $	*/
+/*	$OpenBSD: abuf.c,v 1.3 2008/08/14 09:39:16 ratchov Exp $	*/
 /*
  * Copyright (c) 2008 Alexandre Ratchov <alex@caoua.org>
  *
@@ -26,12 +26,6 @@
  *
  * TODO:
  *
- *	(easy) create abuf_wcommitblk(), abuf_rdiscardblk() instead of tweeking
- *	the fifo pointers by hand. But first, find shorter function names...
- *
- *	(easy) dont initialize aproc-specific stuff in abuf_new(), let the
- *	aproc xxx_new() routines do it
- *
  *	(hard) make abuf_fill() a boolean depending on whether
  *	eof is reached. So the caller can do:
  *
@@ -107,6 +101,27 @@ abuf_rgetblk(struct abuf *buf, unsigned *rsize, unsigned ofs)
 }
 
 /*
+ * Discard the block at the start postion
+ */
+void
+abuf_rdiscard(struct abuf *buf, unsigned count)
+{
+	buf->used -= count;
+	buf->start += count;
+	if (buf->start >= buf->len)
+		buf->start -= buf->len;
+}
+
+/*
+ * Commit the data written at the end postion
+ */
+void
+abuf_wcommit(struct abuf *buf, unsigned count)
+{
+	buf->used += count;
+}
+
+/*
  * Get a pointer to the writable block at offset ofs.
  */
 unsigned char *