From dan@dan.emsphone.com  Mon Mar 13 15:40:13 2000
Return-Path: <dan@dan.emsphone.com>
Received: from dan.emsphone.com (dan.emsphone.com [199.67.51.101])
	by hub.freebsd.org (Postfix) with ESMTP id 30E3B37B6B8
	for <FreeBSD-gnats-submit@freebsd.org>; Mon, 13 Mar 2000 15:40:11 -0800 (PST)
	(envelope-from dan@dan.emsphone.com)
Received: (from dan@localhost)
	by dan.emsphone.com (8.9.3/8.9.3) id RAA46549;
	Mon, 13 Mar 2000 17:40:04 -0600 (CST)
	(envelope-from dan)
Message-Id: <200003132340.RAA46549@dan.emsphone.com>
Date: Mon, 13 Mar 2000 17:40:04 -0600 (CST)
From: dnelson@emsphone.com
Sender: dan@dan.emsphone.com
To: FreeBSD-gnats-submit@freebsd.org
Subject: sendfile() has no pthreads wrapper
X-Send-Pr-Version: 3.2

>Number:         17366
>Category:       bin
>Synopsis:       sendfile() has no pthreads wrapper
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    jasone
>State:          closed
>Quarter:        
>Keywords:       
>Date-Required:  
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Mar 13 15:50:01 PST 2000
>Closed-Date:    Tue May 16 14:08:42 PDT 2000
>Last-Modified:  Tue May 16 14:10:23 PDT 2000
>Originator:     Dan Nelson
>Release:        FreeBSD 4.0-CURRENT i386
>Organization:
Executive Marketing Service, Inc.
>Environment:

FreeBSD dan.emsphone.com 4.0-CURRENT FreeBSD 4.0-CURRENT #49: Thu Feb 10 09:22:17 CST 2000     dan@dan.emsphone.com:/usr/src/sys/compile/DANSMP  i386

	

>Description:

There is no pthreads wrapper for the sendfile() call.  This causes a
problem if someone tries to call sendfile() on a blocking socket. 
Pthreads always set sockets to non-blocking, and sendfile() will return
EAGAIN on non-blocking sockets instead of blocking and sending the
file.

Even though sendfile() doesn't make much sense with out current
user-threads implementation, POLA suggests that a threaded sendfile()
should behave the same as a non-threaded sendfile() from the point of
view of the application.

>How-To-Repeat:

call sendfile() on a blocking socket in a threaded application.

>Fix:

write a sendfile() wrapper that does the right thing.


>Release-Note:
>Audit-Trail:
Responsible-Changed-From-To: freebsd-bugs->jasone 
Responsible-Changed-By: jasone 
Responsible-Changed-When: Mon Mar 13 21:34:52 PST 2000 
Responsible-Changed-Why:  
Over to maintainer. 

From: Jason Evans <jasone@canonware.com>
To: dnelson@emsphone.com
Cc: FreeBSD-gnats-submit@freebsd.org
Subject: Re: bin/17366: sendfile() has no pthreads wrapper
Date: Fri, 24 Mar 2000 16:43:08 -0800

 --YZ5djTAD1cGYuMQK
 Content-Type: text/plain; charset=us-ascii
 
 Here's a completely untested patch (well, it compiles).  I'm going to be
 out of town for the next four weeks, so unless someone can verify today
 that this at least sort of works, it is going to be a long while before I
 can commit it.
 
 Jason
 
 --YZ5djTAD1cGYuMQK
 Content-Type: text/plain; charset=us-ascii
 Content-Disposition: attachment; filename="sendfile.diff"
 
 Index: Makefile
 ===================================================================
 RCS file: /home/ncvs/src/lib/libc_r/Makefile,v
 retrieving revision 1.24
 diff -u -r1.24 Makefile
 --- Makefile	2000/01/27 23:06:56	1.24
 +++ Makefile	2000/03/25 00:39:35
 @@ -31,7 +31,7 @@
  	flock.o fpathconf.o fstat.o fstatfs.o fsync.o getdirentries.o \
  	getlogin.o getpeername.o getsockname.o getsockopt.o ioctl.o listen.o \
  	msync.o nanosleep.o nfssvc.o open.o poll.o read.o readv.o recvfrom.o \
 -	recvmsg.o sched_yield.o select.o sendmsg.o sendto.o \
 +	recvmsg.o sched_yield.o select.o sendfile.o sendmsg.o sendto.o \
  	setsockopt.o shutdown.o sigaction.o sigaltstack.o \
  	signanosleep.o sigpending.o sigprocmask.o sigreturn.o sigsetmask.o \
  	sigsuspend.o socket.o \
 Index: uthread/Makefile.inc
 ===================================================================
 RCS file: /home/ncvs/src/lib/libc_r/uthread/Makefile.inc,v
 retrieving revision 1.23
 diff -u -r1.23 Makefile.inc
 --- uthread/Makefile.inc	2000/01/27 23:06:57	1.23
 +++ uthread/Makefile.inc	2000/03/25 00:39:36
 @@ -92,6 +92,7 @@
  	uthread_select.c \
  	uthread_self.c \
  	uthread_sem.c \
 +	uthread_sendfile.c \
  	uthread_sendmsg.c \
  	uthread_sendto.c \
  	uthread_seterrno.c \
 --- /dev/null	Fri Mar 24 16:10:23 2000
 +++ uthread/uthread_sendfile.c	Fri Mar 24 16:37:43 2000
 @@ -0,0 +1,149 @@
 +/*
 + * Copyright (C) 2000 Jason Evans <jasone@canonware.com>.
 + * All rights reserved.
 + * 
 + * Redistribution and use in source and binary forms, with or without
 + * modification, are permitted provided that the following conditions
 + * are met:
 + * 1. Redistributions of source code must retain the above copyright
 + *    notice(s), this list of conditions and the following disclaimer as
 + *    the first lines of this file unmodified other than the possible
 + *    addition of one or more copyright notices.
 + * 2. Redistributions in binary form must reproduce the above copyright
 + *    notice(s), this list of conditions and the following disclaimer in
 + *    the documentation and/or other materials provided with the
 + *    distribution.
 + * 
 + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
 + * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 + * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
 + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 + * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 + * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 + * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 + *
 + * $FreeBSD$
 + */
 +
 +#include <sys/fcntl.h>
 +#include <sys/types.h>
 +#include <sys/socket.h>
 +#include <sys/uio.h>
 +#include <errno.h>
 +#ifdef _THREAD_SAFE
 +#include <pthread.h>
 +#include "pthread_private.h"
 +
 +int
 +sendfile(int fd, int s, off_t offset, size_t nbytes, struct sf_hdtr *hdtr,
 +    off_t *sbytes, int flags)
 +{
 +	int	ret, type, blocking;
 +	ssize_t wvret, num = 0;
 +	off_t	n, nwritten = 0;
 +
 +	/* Write the headers if any. */
 +	if ((hdtr != NULL) && (hdtr->headers != NULL)) {
 +		if (wvret = writev(s, hdtr->headers, hdtr->hdr_cnt) == -1) {
 +			ret = -1;
 +			goto ERROR;
 +		} else
 +			nwritten += wvret;
 +	}
 +	
 +	/* Lock the descriptors. */
 +	if ((ret = _FD_LOCK(fd, FD_READ, NULL)) != 0) {
 +		goto ERROR;
 +	}
 +	if ((ret = _FD_LOCK(s, FD_WRITE, NULL)) != 0) {
 +		goto ERROR_1;
 +	}
 +	
 +	/* Check the descriptor access modes. */
 +	type = _thread_fd_table[fd]->flags & O_ACCMODE;
 +	if (type != O_RDONLY && type != O_RDWR) {
 +		/* File is not open for read. */
 +		errno = EBADF;
 +		goto ERROR_2;
 +	}
 +	type = _thread_fd_table[s]->flags & O_ACCMODE;
 +	if (type != O_WRONLY && type != O_RDWR) {
 +		/* File is not open for write. */
 +		errno = EBADF;
 +		goto ERROR_2;
 +	}
 +
 +	/* Check if file operations are to block */
 +	blocking = ((_thread_fd_table[s]->flags & O_NONBLOCK) == 0);
 +	
 +	/*
 +	 * Loop while no error occurs and until the expected number of bytes are
 +	 * written.
 +	 */
 +	for (;;) {
 +		/* Perform a non-blocking sendfile syscall. */
 +		ret = _thread_sys_sendfile(fd, s, offset + num, nbytes - num,
 +		    NULL, &n, flags);
 +
 +		if (ret == 0) {
 +			/* Writing completed. */
 +			num += n;
 +			break;
 +		} else if ((blocking) && (ret == -1) && (errno == EAGAIN)) {
 +			/*
 +			 * Some bytes were written but there are still more to
 +			 * write.
 +			 */
 +			
 +			/* Update the count of bytes written. */
 +			num += n;
 +
 +			_thread_run->data.fd.fd = fd;
 +			_thread_kern_set_timeout(NULL);
 +
 +			/* Reset the interrupted operation flag: */
 +			_thread_run->interrupted = 0;
 +
 +			_thread_kern_sched_state(PS_FDW_WAIT, __FILE__,
 +			    __LINE__);
 +
 +			if (_thread_run->interrupted) {
 +				/* Interrupted by a signal.  Return an error. */
 +				ret = -1;
 +				break;
 +			}
 +		} else {
 +			/* Error. */
 +			break;
 +		}
 +	}
 +
 +  ERROR_2:
 +	_FD_UNLOCK(s, FD_WRITE);
 +  ERROR_1:
 +	_FD_UNLOCK(fd, FD_READ);
 +  ERROR:
 +	if (ret == 0) {
 +		/* Write the trailers, if any. */
 +		if ((hdtr != NULL) && (hdtr->trailers != NULL)) {
 +			if (wvret = writev(s, hdtr->trailers, hdtr->trl_cnt)
 +			    == -1)
 +				ret = -1;
 +			else
 +				nwritten += wvret;
 +		}
 +	}
 +	if (sbytes != NULL) {
 +		/*
 +		 * Number of bytes written in headers/trailers, plus in the main
 +		 * sendfile() loop.
 +		 */
 +		*sbytes = nwritten + num;
 +	}
 +	return ret;
 +}
 +#endif
 
 --YZ5djTAD1cGYuMQK--
 
State-Changed-From-To: open->closed 
State-Changed-By: jasone 
State-Changed-When: Tue May 16 14:08:42 PDT 2000 
State-Changed-Why:  
A fix was checked in to -current almost three weeks ago, with no feedback. 
>Unformatted:
 Dan Nelson
