NetBSD/sys/miscfs/procfs/procfs_ctl.c

240 lines
6.0 KiB
C

/*
* Copyright (c) 1993 The Regents of the University of California.
* Copyright (c) 1993 Jan-Simon Pendry
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Jan-Simon Pendry.
*
* 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, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
*
* From:
* Id: procfs_ctl.c,v 4.1 1993/12/17 10:47:45 jsp Rel
*
* $Id: procfs_ctl.c,v 1.7 1994/01/20 21:23:05 ws Exp $
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/vnode.h>
#include <sys/ptrace.h>
#include <sys/ioctl.h>
#include <sys/tty.h>
#include <sys/resource.h>
#include <sys/resourcevar.h>
#include <miscfs/procfs/procfs.h>
/*
* True iff process (p) is in trace wait state
*/
#define TRACE_WAIT_P(p) \
((p)->p_stat == SSTOP && \
((p)->p_flag & STRC))
#define PROCFS_CTL_ATTACH 1
#define PROCFS_CTL_DETACH 2
#define PROCFS_CTL_STEP 3
#define PROCFS_CTL_RUN 4
#define PROCFS_CTL_WAIT 5
static procfs_namemap_t ctlnames[] = {
/* special /proc commands */
{ "attach", PROCFS_CTL_ATTACH },
{ "detach", PROCFS_CTL_DETACH },
{ "step", PROCFS_CTL_STEP },
{ "run", PROCFS_CTL_RUN },
{ 0 },
};
extern procfs_namemap_t procfs_signames[];
static int
procfs_control(curp, p, op)
struct proc *curp;
struct proc *p;
int op;
{
int error;
/*
* Target process must be stopped and
* be set up for tracing (SFSTRC flag set).
* Of course ATTACH is allowed any time.
* Allow DETACH to take place at any time for sanity.
*/
switch (op) {
case PROCFS_CTL_ATTACH:
case PROCFS_CTL_DETACH:
break;
default:
if (!TRACE_WAIT_P(p))
return (EBUSY);
}
/*
* do single-step fixup if needed
*/
FIX_SSTEP(p);
switch (op) {
case PROCFS_CTL_ATTACH:
/*
* Attach - attaches the target process for debugging
* by the calling process.
*/
/* check whether already being traced */
if (p->p_flag & STRC)
return (EBUSY);
/* can't trace yourself! */
/* DO WE REALLY NEED THIS RESTRICTION??? */
if (curp && p->p_pid == curp->p_pid)
return (EINVAL);
/*
* Go ahead and set the trace flag.
* Save the old parent (it's reset in
* _DETACH, and also in kern_exit.c:wait4()
* Reparent the process so that the tracing
* proc gets to see all the action.
* Stop the target.
*/
p->p_flag |= STRC|SFSTRC;
psignal(p, SIGSTOP);
break;
/*
* Detach. Cleans up the target process, reparent it if possible
* and set it running once more.
*/
case PROCFS_CTL_DETACH:
/* if not being traced, then this is a painless no-op */
if ((p->p_flag & SFSTRC) == 0)
return (0);
if (error = process_sstep(p, 0))
return error;
/* not being traced any more */
p->p_flag &= ~(STRC|SFSTRC);
setrun(p);
return 0;
/*
* Step. Let the target process execute a single instruction.
*/
case PROCFS_CTL_STEP:
/* Fall through */
/*
* Run. Let the target process continue running until a breakpoint
* or some other trap.
*/
case PROCFS_CTL_RUN:
if (error = process_sstep(p, op == PROCFS_CTL_STEP))
return error;
setrun(p);
break;
default:
panic("procfs_control");
}
/*
* Wait for the target process to stop.
*/
while ((p->p_stat != SSTOP) &&
(p->p_flag & SFSTRC)) {
if (error = tsleep((caddr_t) p,
PWAIT|PCATCH, "procfs", 0))
return error;
}
if (!TRACE_WAIT_P(p))
return EBUSY;
return 0;
}
pfs_doctl(curp, p, pfs, uio)
struct proc *curp;
struct pfsnode *pfs;
struct uio *uio;
struct proc *p;
{
int len = uio->uio_resid;
int xlen;
int error;
char msg[PROCFS_CTLLEN+1];
procfs_namemap_t *nm;
/*
* If we are debugging, you might read the stop signal.
*/
if (uio->uio_rw == UIO_READ && TRACE_WAIT_P(p)) {
if (p->p_xstat) {
if (error = pfs_readnote(p->p_xstat, uio))
return error;
p->p_xstat = 0;
}
return 0;
}
if (uio->uio_rw != UIO_WRITE)
return (EOPNOTSUPP);
xlen = PROCFS_CTLLEN;
error = procfs_getuserstr(uio, msg, &xlen);
if (error)
return (error);
/*
* Map debug control. Unknown commands return EOPNOTSUPP.
*/
error = EOPNOTSUPP;
nm = procfs_findname(ctlnames, msg, xlen);
if (nm) {
error = procfs_control(curp, p, nm->nm_val);
} else if (TRACE_WAIT_P(p)) {
/*
* If we are debugging, it might be a signal.
*/
nm = procfs_findname(procfs_signames, msg, xlen);
if (nm) {
p->p_xstat = nm->nm_val;
error = 0;
}
}
return (error);
}