From: Ben Gras <ben@minix3.org>
Date: Wed, 5 Mar 2014 14:12:54 +0000 (+0100)
Subject: vfs: call pipe_check before reviving select()
X-Git-Tag: v3.3.0~404
X-Git-Url: http://zhaoyanbai.com/repos/%22http:/www.isc.org/icons/doxygen.png?a=commitdiff_plain;h=013226c417480e0645e83b8ca4ef7cfe64614446;p=minix.git

vfs: call pipe_check before reviving select()

	. select callback on close() on a pipe
	  would falsely revive a read-select on
	  the pipe
	. the extra pipe_check catches it
	. fixes the new import of the netbsd
	  make in -j N mode (make jobs that communicate
	  with pipes)
---

diff --git a/servers/vfs/pipe.c b/servers/vfs/pipe.c
index ce0909727..f9e2c6ad6 100644
--- a/servers/vfs/pipe.c
+++ b/servers/vfs/pipe.c
@@ -392,7 +392,16 @@ int count;			/* max number of processes to release */
 		if (f->filp_count < 1 || !(f->filp_pipe_select_ops & selop) ||
 		    f->filp_vno != vp)
 			continue;
+
+		/* Do a pipe_check to see if we really want to callback this
+		 * select; a close() doesn't always warrant it.
+		 */
+		if(pipe_check(f, op == VFS_READ ? READING : WRITING,
+			f->filp_flags & ~O_NONBLOCK, 1, 1) == SUSPEND) {
+			continue;
+		}
 		select_callback(f, selop);
+
 		f->filp_pipe_select_ops &= ~selop;
 	}
   }