Added pread and pwrite. These functions are defined by the X/Open

Threads Extension.  (Note: We use the same syscall numbers as NetBSD.)

Submitted by:	John Plevyak <jplevyak@inktomi.com>

8 files changed, 159 insertions, 8 deletions

diff --git a/sys/kern/init_sysent.c b/sys/kern/init_sysent.c
index c31ed46..c258380 100644
--- a/sys/kern/init_sysent.c
+++ b/sys/kern/init_sysent.c
@@ -192,8 +192,8 @@ struct sysent sysent[] = {
 	{ 6, (sy_call_t *)msgsys },			/* 170 = msgsys */
 	{ 4, (sy_call_t *)shmsys },			/* 171 = shmsys */
 	{ 0, (sy_call_t *)nosys },			/* 172 = nosys */
-	{ 0, (sy_call_t *)nosys },			/* 173 = nosys */
-	{ 0, (sy_call_t *)nosys },			/* 174 = nosys */
+	{ 5, (sy_call_t *)pread },			/* 173 = pread */
+	{ 5, (sy_call_t *)pwrite },			/* 174 = pwrite */
 	{ 0, (sy_call_t *)nosys },			/* 175 = nosys */
 	{ 1, (sy_call_t *)ntp_adjtime },		/* 176 = ntp_adjtime */
 	{ 0, (sy_call_t *)nosys },			/* 177 = sfork */
diff --git a/sys/kern/sys_generic.c b/sys/kern/sys_generic.c
index b607f71..e19fed8 100644
--- a/sys/kern/sys_generic.c
+++ b/sys/kern/sys_generic.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)sys_generic.c	8.5 (Berkeley) 1/21/94
- * $Id: sys_generic.c,v 1.44 1999/01/27 21:49:57 dillon Exp $
+ * $Id: sys_generic.c,v 1.45 1999/01/29 08:10:35 bde Exp $
  */
 
 #include "opt_ktrace.h"
@@ -132,6 +132,70 @@ read(p, uap)
 }
 
 /*
+ * pread system call.
+ */
+#ifndef _SYS_SYSPROTO_H_
+struct pread_args {
+	int	fd;
+	void	*buf;
+	size_t	nbyte;
+        off_t   offset;
+};
+#endif
+/* ARGSUSED */
+int
+pread(p, uap)
+	struct proc *p;
+	register struct pread_args *uap;
+{
+	register struct file *fp;
+	register struct filedesc *fdp = p->p_fd;
+	struct uio auio;
+	struct iovec aiov;
+	long cnt, error = 0;
+#ifdef KTRACE
+	struct iovec ktriov;
+#endif
+
+	if (((u_int)uap->fd) >= fdp->fd_nfiles ||
+	    (fp = fdp->fd_ofiles[uap->fd]) == NULL ||
+	    (fp->f_flag & FREAD) == 0)
+		return (EBADF);
+	if (fp->f_type != DTYPE_VNODE)
+		return (ESPIPE);
+	aiov.iov_base = (caddr_t)uap->buf;
+	aiov.iov_len = uap->nbyte;
+	auio.uio_iov = &aiov;
+	auio.uio_iovcnt = 1;
+	auio.uio_offset = uap->offset;
+	if (uap->nbyte > INT_MAX)
+		return (EINVAL);
+	auio.uio_resid = uap->nbyte;
+	auio.uio_rw = UIO_READ;
+	auio.uio_segflg = UIO_USERSPACE;
+	auio.uio_procp = p;
+#ifdef KTRACE
+	/*
+	 * if tracing, save a copy of iovec
+	 */
+	if (KTRPOINT(p, KTR_GENIO))
+		ktriov = aiov;
+#endif
+	cnt = uap->nbyte;
+	if ((error = (*fp->f_ops->fo_read)(fp, &auio, fp->f_cred)))
+		if (auio.uio_resid != cnt && (error == ERESTART ||
+		    error == EINTR || error == EWOULDBLOCK))
+			error = 0;
+	cnt -= auio.uio_resid;
+#ifdef KTRACE
+	if (KTRPOINT(p, KTR_GENIO) && error == 0)
+		ktrgenio(p->p_tracep, uap->fd, UIO_READ, &ktriov, cnt, error);
+#endif
+	p->p_retval[0] = cnt;
+	return (error);
+}
+
+/*
  * Scatter read system call.
  */
 #ifndef _SYS_SYSPROTO_H_
@@ -285,6 +349,73 @@ write(p, uap)
 }
 
 /*
+ * pwrite system call
+ */
+#ifndef _SYS_SYSPROTO_H_
+struct pwrite_args {
+	int	fd;
+	const void *buf;
+	size_t	nbyte;
+        off_t   offset;
+};
+#endif
+int
+pwrite(p, uap)
+	struct proc *p;
+	register struct pwrite_args *uap;
+{
+	register struct file *fp;
+	register struct filedesc *fdp = p->p_fd;
+	struct uio auio;
+	struct iovec aiov;
+	long cnt, error = 0;
+#ifdef KTRACE
+	struct iovec ktriov;
+#endif
+
+	if (((u_int)uap->fd) >= fdp->fd_nfiles ||
+	    (fp = fdp->fd_ofiles[uap->fd]) == NULL ||
+	    (fp->f_flag & FWRITE) == 0)
+		return (EBADF);
+	if (fp->f_type != DTYPE_VNODE)
+		return (ESPIPE);
+	aiov.iov_base = (caddr_t)uap->buf;
+	aiov.iov_len = uap->nbyte;
+	auio.uio_iov = &aiov;
+	auio.uio_iovcnt = 1;
+	auio.uio_offset = uap->offset;
+	if (uap->nbyte > INT_MAX)
+		return (EINVAL);
+	auio.uio_resid = uap->nbyte;
+	auio.uio_rw = UIO_WRITE;
+	auio.uio_segflg = UIO_USERSPACE;
+	auio.uio_procp = p;
+#ifdef KTRACE
+	/*
+	 * if tracing, save a copy of iovec
+	 */
+	if (KTRPOINT(p, KTR_GENIO))
+		ktriov = aiov;
+#endif
+	cnt = uap->nbyte;
+	if ((error = (*fp->f_ops->fo_write)(fp, &auio, fp->f_cred))) {
+		if (auio.uio_resid != cnt && (error == ERESTART ||
+		    error == EINTR || error == EWOULDBLOCK))
+			error = 0;
+		if (error == EPIPE)
+			psignal(p, SIGPIPE);
+	}
+	cnt -= auio.uio_resid;
+#ifdef KTRACE
+	if (KTRPOINT(p, KTR_GENIO) && error == 0)
+		ktrgenio(p->p_tracep, uap->fd, UIO_WRITE,
+		    &ktriov, cnt, error);
+#endif
+	p->p_retval[0] = cnt;
+	return (error);
+}
+
+/*
  * Gather write system call
  */
 #ifndef _SYS_SYSPROTO_H_
diff --git a/sys/kern/syscalls.c b/sys/kern/syscalls.c
index 22e9e8e..d0d12f3 100644
--- a/sys/kern/syscalls.c
+++ b/sys/kern/syscalls.c
@@ -179,8 +179,8 @@ char *syscallnames[] = {
 	"msgsys",			/* 170 = msgsys */
 	"shmsys",			/* 171 = shmsys */
 	"#172",			/* 172 = nosys */
-	"#173",			/* 173 = nosys */
-	"#174",			/* 174 = nosys */
+	"pread",			/* 173 = pread */
+	"pwrite",			/* 174 = pwrite */
 	"#175",			/* 175 = nosys */
 	"ntp_adjtime",			/* 176 = ntp_adjtime */
 	"#177",			/* 177 = sfork */
diff --git a/sys/kern/syscalls.master b/sys/kern/syscalls.master
index 6772363..30b39c4 100644
--- a/sys/kern/syscalls.master
+++ b/sys/kern/syscalls.master
@@ -1,4 +1,4 @@
-	$Id: syscalls.master,v 1.54 1998/11/05 14:28:24 dg Exp $
+	$Id: syscalls.master,v 1.55 1998/11/11 12:45:14 peter Exp $
 ;	from: @(#)syscalls.master	8.2 (Berkeley) 1/13/94
 ;
 ; System call name/number master file.
@@ -266,8 +266,8 @@
 171	STD	BSD	{ int shmsys(int which, int a2, int a3, int a4); }
 ; XXX should be		{ int shmsys(int which, ...); }
 172	UNIMPL	NOHIDE	nosys
-173	UNIMPL	NOHIDE	nosys
-174	UNIMPL	NOHIDE	nosys
+173	STD	POSIX	{ ssize_t pread(int fd, void *buf, size_t nbyte, off_t offset); }
+174	STD	POSIX	{ ssize_t pwrite(int fd, const void *buf, size_t nbyte, off_t offset); }
 175	UNIMPL	NOHIDE	nosys
 176	STD	BSD	{ int ntp_adjtime(struct timex *tp); }
 177	UNIMPL	NOHIDE	sfork (BSD/OS 2.x)
diff --git a/sys/sys/syscall-hide.h b/sys/sys/syscall-hide.h
index 814bfec..11b5b2c 100644
--- a/sys/sys/syscall-hide.h
+++ b/sys/sys/syscall-hide.h
@@ -158,6 +158,8 @@ HIDE_BSD(rtprio)
 HIDE_BSD(semsys)
 HIDE_BSD(msgsys)
 HIDE_BSD(shmsys)
+HIDE_POSIX(pread)
+HIDE_POSIX(pwrite)
 HIDE_BSD(ntp_adjtime)
 HIDE_POSIX(setgid)
 HIDE_BSD(setegid)
diff --git a/sys/sys/syscall.h b/sys/sys/syscall.h
index 464ea91..b4fcab9 100644
--- a/sys/sys/syscall.h
+++ b/sys/sys/syscall.h
@@ -166,6 +166,8 @@
 #define	SYS_semsys	169
 #define	SYS_msgsys	170
 #define	SYS_shmsys	171
+#define	SYS_pread	173
+#define	SYS_pwrite	174
 #define	SYS_ntp_adjtime	176
 #define	SYS_setgid	181
 #define	SYS_setegid	182
diff --git a/sys/sys/syscall.mk b/sys/sys/syscall.mk
index 581290a..9e7e23c 100644
--- a/sys/sys/syscall.mk
+++ b/sys/sys/syscall.mk
@@ -123,6 +123,8 @@ MIASM =  \
 	semsys.o \
 	msgsys.o \
 	shmsys.o \
+	pread.o \
+	pwrite.o \
 	ntp_adjtime.o \
 	setgid.o \
 	setegid.o \
diff --git a/sys/sys/sysproto.h b/sys/sys/sysproto.h
index 71f9492..7a7d1bc 100644
--- a/sys/sys/sysproto.h
+++ b/sys/sys/sysproto.h
@@ -542,6 +542,18 @@ struct	shmsys_args {
 	int	a3;	char a3_[PAD_(int)];
 	int	a4;	char a4_[PAD_(int)];
 };
+struct	pread_args {
+	int	fd;	char fd_[PAD_(int)];
+	void *	buf;	char buf_[PAD_(void *)];
+	size_t	nbyte;	char nbyte_[PAD_(size_t)];
+	off_t	offset;	char offset_[PAD_(off_t)];
+};
+struct	pwrite_args {
+	int	fd;	char fd_[PAD_(int)];
+	const void *	buf;	char buf_[PAD_(const void *)];
+	size_t	nbyte;	char nbyte_[PAD_(size_t)];
+	off_t	offset;	char offset_[PAD_(off_t)];
+};
 struct	ntp_adjtime_args {
 	struct timex *	tp;	char tp_[PAD_(struct timex *)];
 };
@@ -1014,6 +1026,8 @@ int	rtprio __P((struct proc *, struct rtprio_args *));
 int	semsys __P((struct proc *, struct semsys_args *));
 int	msgsys __P((struct proc *, struct msgsys_args *));
 int	shmsys __P((struct proc *, struct shmsys_args *));
+int	pread __P((struct proc *, struct pread_args *));
+int	pwrite __P((struct proc *, struct pwrite_args *));
 int	ntp_adjtime __P((struct proc *, struct ntp_adjtime_args *));
 int	setgid __P((struct proc *, struct setgid_args *));
 int	setegid __P((struct proc *, struct setegid_args *));