-/* Low level Unix child interface to ptrace, for GDB when running under Unix.
+/* Low-level child interface to ptrace.
- Copyright 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996,
- 1998, 1999, 2000, 2001, 2002, 2004 Free Software Foundation, Inc.
+ Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998,
+ 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2008, 2009
+ Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
-#include "observer.h"
-#include "gdb_ptrace.h"
-#include "inflow.h"
-#include "inferior.h"
-#include "regcache.h"
#include "command.h"
+#include "inferior.h"
+#include "inflow.h"
+#include "terminal.h"
#include "gdbcore.h"
-#include "inf-child.h"
-#include "gdbcmd.h"
-#include "gdb_string.h"
+#include "regcache.h"
-#include <sys/wait.h>
+#include "gdb_assert.h"
+#include "gdb_string.h"
+#include "gdb_ptrace.h"
+#include "gdb_wait.h"
#include <signal.h>
-/* HACK: Save the ptrace ops returned by ptrace_target. */
-static struct target_ops *ptrace_ops_hack;
+#include "inf-ptrace.h"
+#include "inf-child.h"
+#include "gdbthread.h"
-static void
-inf_ptrace_kill_inferior (void)
-{
- int status;
- int pid = PIDGET (inferior_ptid);
+\f
- if (pid == 0)
- return;
+#ifdef PT_GET_PROCESS_STATE
- /* This once used to call "kill" to kill the inferior just in case
- the inferior was still running. As others have noted in the past
- (kingdon) there shouldn't be any way to get here if the inferior
- is still running -- else there's a major problem elsewere in gdb
- and it needs to be fixed.
+static int
+inf_ptrace_follow_fork (struct target_ops *ops, int follow_child)
+{
+ pid_t pid, fpid;
+ ptrace_state_t pe;
+ struct thread_info *last_tp = NULL;
- The kill call causes problems under hpux10, so it's been removed;
- if this causes problems we'll deal with them as they arise. */
- ptrace (PT_KILL, pid, (PTRACE_TYPE_ARG3) 0, 0);
- wait (&status);
- target_mourn_inferior ();
-}
+ /* FIXME: kettenis/20050720: This stuff should really be passed as
+ an argument by our caller. */
+ {
+ ptid_t ptid;
+ struct target_waitstatus status;
-/* Resume execution of the inferior process. If STEP is nonzero,
- single-step it. If SIGNAL is nonzero, give it that signal. */
+ get_last_target_status (&ptid, &status);
+ gdb_assert (status.kind == TARGET_WAITKIND_FORKED);
-static void
-inf_ptrace_resume (ptid_t ptid, int step, enum target_signal signal)
-{
- int request = PT_CONTINUE;
- int pid = PIDGET (ptid);
+ pid = ptid_get_pid (ptid);
+ last_tp = find_thread_pid (ptid);
+ }
- if (pid == -1)
- /* Resume all threads. */
- /* I think this only gets used in the non-threaded case, where
- "resume all threads" and "resume inferior_ptid" are the
- same. */
- pid = PIDGET (inferior_ptid);
+ if (ptrace (PT_GET_PROCESS_STATE, pid,
+ (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1)
+ perror_with_name (("ptrace"));
- if (step)
+ gdb_assert (pe.pe_report_event == PTRACE_FORK);
+ fpid = pe.pe_other_pid;
+
+ if (follow_child)
{
- /* If this system does not support PT_STEP, a higher level
- function will have called single_step() to transmute the step
- request into a continue request (by setting breakpoints on
- all possible successor instructions), so we don't have to
- worry about that here. */
- request = PT_STEP;
- }
+ /* Copy user stepping state to the new inferior thread. */
+ struct breakpoint *step_resume_breakpoint = last_tp->step_resume_breakpoint;
+ CORE_ADDR step_range_start = last_tp->step_range_start;
+ CORE_ADDR step_range_end = last_tp->step_range_end;
+ struct frame_id step_frame_id = last_tp->step_frame_id;
+ struct inferior *parent_inf, *child_inf;
+ struct thread_info *tp;
- /* An address of (PTRACE_TYPE_ARG3)1 tells ptrace to continue from
- where it was. If GDB wanted it to start some other way, we have
- already written a new PC value to the child. */
- errno = 0;
- ptrace (request, pid, (PTRACE_TYPE_ARG3) 1, target_signal_to_host (signal));
- if (errno != 0)
- perror_with_name ("ptrace");
-}
+ /* Otherwise, deleting the parent would get rid of this
+ breakpoint. */
+ last_tp->step_resume_breakpoint = NULL;
-/* Set an upper limit on alloca. */
-#define GDB_MAX_ALLOCA 0x1000
+ parent_inf = find_inferior_pid (pid);
-/* NOTE! I tried using PTRACE_READDATA, etc., to read and write memory
- in the NEW_SUN_PTRACE case. It ought to be straightforward. But
- it appears that writing did not write the data that I specified. I
- cannot understand where it got the data that it actually did
- write. */
+ /* Add the child. */
+ child_inf = add_inferior (fpid);
+ child_inf->attach_flag = parent_inf->attach_flag;
+ copy_terminal_info (child_inf, parent_inf);
-/* Copy LEN bytes to or from inferior's memory starting at MEMADDR to
- debugger memory starting at MYADDR. Copy to inferior if WRITE is
- nonzero. TARGET is ignored.
+ /* Before detaching from the parent, remove all breakpoints from
+ it. */
+ remove_breakpoints ();
- Returns the length copied, which is either the LEN argument or
- zero. This xfer function does not do partial moves, since
- ptrace_ops_hack doesn't allow memory operations to cross below us in the
- target stack anyway. */
+ if (ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, 0) == -1)
+ perror_with_name (("ptrace"));
-int
-inf_ptrace_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int write,
- struct mem_attrib *attrib, struct target_ops *target)
-{
- int i;
- /* Round starting address down to longword boundary. */
- CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_TYPE_RET);
- /* Round ending address up; get number of longwords that makes. */
- int count = ((((memaddr + len) - addr) + sizeof (PTRACE_TYPE_RET) - 1)
- / sizeof (PTRACE_TYPE_RET));
- int alloc = count * sizeof (PTRACE_TYPE_RET);
- PTRACE_TYPE_RET *buffer;
- struct cleanup *old_chain = NULL;
+ /* Switch inferior_ptid out of the parent's way. */
+ inferior_ptid = pid_to_ptid (fpid);
-#ifdef PT_IO
- /* OpenBSD 3.1, NetBSD 1.6 and FreeBSD 5.0 have a new PT_IO request
- that promises to be much more efficient in reading and writing
- data in the traced process's address space. */
+ /* Delete the parent. */
+ detach_inferior (pid);
- {
- struct ptrace_io_desc piod;
+ tp = add_thread_silent (inferior_ptid);
- /* NOTE: We assume that there are no distinct address spaces for
- instruction and data. */
- piod.piod_op = write ? PIOD_WRITE_D : PIOD_READ_D;
- piod.piod_offs = (void *) memaddr;
- piod.piod_addr = myaddr;
- piod.piod_len = len;
+ tp->step_resume_breakpoint = step_resume_breakpoint;
+ tp->step_range_start = step_range_start;
+ tp->step_range_end = step_range_end;
+ tp->step_frame_id = step_frame_id;
- if (ptrace (PT_IO, PIDGET (inferior_ptid), (caddr_t) & piod, 0) == -1)
- {
- /* If the PT_IO request is somehow not supported, fallback on
- using PT_WRITE_D/PT_READ_D. Otherwise we will return zero
- to indicate failure. */
- if (errno != EINVAL)
- return 0;
- }
- else
- {
- /* Return the actual number of bytes read or written. */
- return piod.piod_len;
- }
- }
-#endif
-
- /* Allocate buffer of that many longwords. */
- if (len < GDB_MAX_ALLOCA)
- {
- buffer = (PTRACE_TYPE_RET *) alloca (alloc);
+ /* Reset breakpoints in the child as appropriate. */
+ follow_inferior_reset_breakpoints ();
}
else
{
- buffer = (PTRACE_TYPE_RET *) xmalloc (alloc);
- old_chain = make_cleanup (xfree, buffer);
- }
+ inferior_ptid = pid_to_ptid (pid);
- if (write)
- {
- /* Fill start and end extra bytes of buffer with existing memory
- data. */
- if (addr != memaddr || len < (int) sizeof (PTRACE_TYPE_RET))
- {
- /* Need part of initial word -- fetch it. */
- buffer[0] = ptrace (PT_READ_I, PIDGET (inferior_ptid),
- (PTRACE_TYPE_ARG3) addr, 0);
- }
+ /* Breakpoints have already been detached from the child by
+ infrun.c. */
- if (count > 1) /* FIXME, avoid if even boundary. */
- {
- buffer[count - 1] =
- ptrace (PT_READ_I, PIDGET (inferior_ptid),
- ((PTRACE_TYPE_ARG3)
- (addr + (count - 1) * sizeof (PTRACE_TYPE_RET))), 0);
- }
+ if (ptrace (PT_DETACH, fpid, (PTRACE_TYPE_ARG3)1, 0) == -1)
+ perror_with_name (("ptrace"));
+ detach_inferior (pid);
+ }
- /* Copy data to be written over corresponding part of buffer. */
- memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_TYPE_RET) - 1)),
- myaddr, len);
+ return 0;
+}
- /* Write the entire buffer. */
- for (i = 0; i < count; i++, addr += sizeof (PTRACE_TYPE_RET))
- {
- errno = 0;
- ptrace (PT_WRITE_D, PIDGET (inferior_ptid),
- (PTRACE_TYPE_ARG3) addr, buffer[i]);
- if (errno)
- {
- /* Using the appropriate one (I or D) is necessary for
- Gould NP1, at least. */
- errno = 0;
- ptrace (PT_WRITE_I, PIDGET (inferior_ptid),
- (PTRACE_TYPE_ARG3) addr, buffer[i]);
- }
- if (errno)
- return 0;
- }
- }
- else
- {
- /* Read all the longwords. */
- for (i = 0; i < count; i++, addr += sizeof (PTRACE_TYPE_RET))
- {
- errno = 0;
- buffer[i] = ptrace (PT_READ_I, PIDGET (inferior_ptid),
- (PTRACE_TYPE_ARG3) addr, 0);
- if (errno)
- return 0;
- QUIT;
- }
+#endif /* PT_GET_PROCESS_STATE */
+\f
- /* Copy appropriate bytes out of the buffer. */
- memcpy (myaddr,
- (char *) buffer + (memaddr & (sizeof (PTRACE_TYPE_RET) - 1)),
- len);
- }
+/* Prepare to be traced. */
- if (old_chain != NULL)
- do_cleanups (old_chain);
- return len;
+static void
+inf_ptrace_me (void)
+{
+ /* "Trace me, Dr. Memory!" */
+ ptrace (PT_TRACE_ME, 0, (PTRACE_TYPE_ARG3)0, 0);
}
-/* Wait for child to do something. Return pid of child, or -1 in case
- of error; store status through argument pointer OURSTATUS. */
+/* Start a new inferior Unix child process. EXEC_FILE is the file to
+ run, ALLARGS is a string containing the arguments to the program.
+ ENV is the environment vector to pass. If FROM_TTY is non-zero, be
+ chatty about it. */
-static ptid_t
-inf_ptrace_wait (ptid_t ptid, struct target_waitstatus *ourstatus)
+static void
+inf_ptrace_create_inferior (struct target_ops *ops,
+ char *exec_file, char *allargs, char **env,
+ int from_tty)
{
- int save_errno;
- int status;
- char *execd_pathname = NULL;
- int exit_status;
- int related_pid;
- int syscall_id;
- enum target_waitkind kind;
int pid;
- do
- {
- set_sigint_trap (); /* Causes SIGINT to be passed on to the
- attached process. */
- set_sigio_trap ();
+ pid = fork_inferior (exec_file, allargs, env, inf_ptrace_me, NULL,
+ NULL, NULL);
- pid = wait (&status);
- target_post_wait (pid_to_ptid (pid), status);
+ push_target (ops);
- save_errno = errno;
+ /* On some targets, there must be some explicit synchronization
+ between the parent and child processes after the debugger
+ forks, and before the child execs the debuggee program. This
+ call basically gives permission for the child to exec. */
- clear_sigio_trap ();
+ target_acknowledge_created_inferior (pid);
- clear_sigint_trap ();
+ /* START_INFERIOR_TRAPS_EXPECTED is defined in inferior.h, and will
+ be 1 or 2 depending on whether we're starting without or with a
+ shell. */
+ startup_inferior (START_INFERIOR_TRAPS_EXPECTED);
- if (pid == -1)
- {
- if (save_errno == EINTR)
- continue;
+ /* On some targets, there must be some explicit actions taken after
+ the inferior has been started up. */
+ target_post_startup_inferior (pid_to_ptid (pid));
+}
- fprintf_unfiltered (gdb_stderr,
- "Child process unexpectedly missing: %s.\n",
- safe_strerror (save_errno));
+#ifdef PT_GET_PROCESS_STATE
- /* Claim it exited with unknown signal. */
- ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
- ourstatus->value.sig = TARGET_SIGNAL_UNKNOWN;
- return pid_to_ptid (-1);
- }
+static void
+inf_ptrace_post_startup_inferior (ptid_t pid)
+{
+ ptrace_event_t pe;
- /* Did it exit?
- */
- if (target_has_exited (pid, status, &exit_status))
- {
- /* ??rehrauer: For now, ignore this. */
- continue;
- }
+ /* Set the initial event mask. */
+ memset (&pe, 0, sizeof pe);
+ pe.pe_set_event |= PTRACE_FORK;
+ if (ptrace (PT_SET_EVENT_MASK, ptid_get_pid (pid),
+ (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1)
+ perror_with_name (("ptrace"));
+}
- if (!target_thread_alive (pid_to_ptid (pid)))
- {
- ourstatus->kind = TARGET_WAITKIND_SPURIOUS;
- return pid_to_ptid (pid);
- }
- }
- while (pid != PIDGET (inferior_ptid)); /* Some other child died or stopped */
+#endif
- store_waitstatus (ourstatus, status);
- return pid_to_ptid (pid);
-}
+/* Clean up a rotting corpse of an inferior after it died. */
-void
-inf_ptrace_post_wait (ptid_t ptid, int wait_status)
+static void
+inf_ptrace_mourn_inferior (struct target_ops *ops)
{
- /* This version of Unix doesn't require a meaningful "post wait"
- operation.
- */
-}
-
-/* Check to see if the given thread is alive.
+ int status;
- FIXME: Is kill() ever the right way to do this? I doubt it, but
- for now we're going to try and be compatable with the old thread
- code. */
+ /* Wait just one more time to collect the inferior's exit status.
+ Do not check whether this succeeds though, since we may be
+ dealing with a process that we attached to. Such a process will
+ only report its exit status to its original parent. */
+ waitpid (ptid_get_pid (inferior_ptid), &status, 0);
-static int
-inf_ptrace_thread_alive (ptid_t ptid)
-{
- pid_t pid = PIDGET (ptid);
+ generic_mourn_inferior ();
- return (kill (pid, 0) != -1);
+ if (!have_inferiors ())
+ unpush_target (ops);
}
-/* Attach to process PID, then initialize for debugging it. */
+/* Attach to the process specified by ARGS. If FROM_TTY is non-zero,
+ be chatty about it. */
static void
-inf_ptrace_attach (char *args, int from_tty)
+inf_ptrace_attach (struct target_ops *ops, char *args, int from_tty)
{
char *exec_file;
- int pid;
+ pid_t pid;
char *dummy;
+ struct inferior *inf;
if (!args)
- error_no_arg ("process-id to attach");
+ error_no_arg (_("process-id to attach"));
dummy = args;
pid = strtol (args, &dummy, 0);
- /* Some targets don't set errno on errors, grrr! */
- if ((pid == 0) && (args == dummy))
- error ("Illegal process-id: %s\n", args);
+ /* Some targets don't set errno on errors, grrr! */
+ if (pid == 0 && args == dummy)
+ error (_("Illegal process-id: %s."), args);
- if (pid == getpid ()) /* Trying to masturbate? */
- error ("I refuse to debug myself!");
+ if (pid == getpid ()) /* Trying to masturbate? */
+ error (_("I refuse to debug myself!"));
if (from_tty)
{
- exec_file = (char *) get_exec_file (0);
+ exec_file = get_exec_file (0);
if (exec_file)
- printf_unfiltered ("Attaching to program: %s, %s\n", exec_file,
+ printf_unfiltered (_("Attaching to program: %s, %s\n"), exec_file,
target_pid_to_str (pid_to_ptid (pid)));
else
- printf_unfiltered ("Attaching to %s\n",
+ printf_unfiltered (_("Attaching to %s\n"),
target_pid_to_str (pid_to_ptid (pid)));
gdb_flush (gdb_stdout);
}
- attach (pid);
+#ifdef PT_ATTACH
+ errno = 0;
+ ptrace (PT_ATTACH, pid, (PTRACE_TYPE_ARG3)0, 0);
+ if (errno != 0)
+ perror_with_name (("ptrace"));
+#else
+ error (_("This system does not support attaching to a process"));
+#endif
inferior_ptid = pid_to_ptid (pid);
- push_target (ptrace_ops_hack);
+
+ inf = add_inferior (pid);
+ inf->attach_flag = 1;
+
+ /* Always add a main thread. If some target extends the ptrace
+ target, it should decorate the ptid later with more info. */
+ add_thread_silent (inferior_ptid);
+
+ push_target(ops);
}
-static void
+#ifdef PT_GET_PROCESS_STATE
+
+void
inf_ptrace_post_attach (int pid)
{
- /* This version of Unix doesn't require a meaningful "post attach"
- operation by a debugger. */
+ ptrace_event_t pe;
+
+ /* Set the initial event mask. */
+ memset (&pe, 0, sizeof pe);
+ pe.pe_set_event |= PTRACE_FORK;
+ if (ptrace (PT_SET_EVENT_MASK, pid,
+ (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1)
+ perror_with_name (("ptrace"));
}
-/* Take a program previously attached to and detaches it. The program
- resumes execution and will no longer stop on signals, etc. We'd
- better not have left any breakpoints in the program or it'll die
- when it hits one. For this to work, it may be necessary for the
- process to have been previously attached. It *might* work if the
- program was started via the normal ptrace (PTRACE_TRACEME). */
+#endif
+
+/* Detach from the inferior, optionally passing it the signal
+ specified by ARGS. If FROM_TTY is non-zero, be chatty about it. */
static void
-inf_ptrace_detach (char *args, int from_tty)
+inf_ptrace_detach (struct target_ops *ops, char *args, int from_tty)
{
- int siggnal = 0;
- int pid = PIDGET (inferior_ptid);
+ pid_t pid = ptid_get_pid (inferior_ptid);
+ int sig = 0;
if (from_tty)
{
char *exec_file = get_exec_file (0);
if (exec_file == 0)
exec_file = "";
- printf_unfiltered ("Detaching from program: %s, %s\n", exec_file,
+ printf_unfiltered (_("Detaching from program: %s, %s\n"), exec_file,
target_pid_to_str (pid_to_ptid (pid)));
gdb_flush (gdb_stdout);
}
if (args)
- siggnal = atoi (args);
+ sig = atoi (args);
- detach (siggnal);
+#ifdef PT_DETACH
+ /* We'd better not have left any breakpoints in the program or it'll
+ die when it hits one. Also note that this may only work if we
+ previously attached to the inferior. It *might* work if we
+ started the process ourselves. */
+ errno = 0;
+ ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, sig);
+ if (errno != 0)
+ perror_with_name (("ptrace"));
+#else
+ error (_("This system does not support detaching from a process"));
+#endif
inferior_ptid = null_ptid;
- unpush_target (ptrace_ops_hack);
-}
-
-/* Get ready to modify the registers array. On machines which store
- individual registers, this doesn't need to do anything. On
- machines which store all the registers in one fell swoop, this
- makes sure that registers contains all the registers from the
- program being debugged. */
+ detach_inferior (pid);
-static void
-inf_ptrace_prepare_to_store (void)
-{
+ if (!have_inferiors ())
+ unpush_target (ops);
}
-/* Print status information about what we're accessing. */
+/* Kill the inferior. */
static void
-inf_ptrace_files_info (struct target_ops *ignore)
+inf_ptrace_kill (struct target_ops *ops)
{
- printf_unfiltered ("\tUsing the running image of %s %s.\n",
- attach_flag ? "attached" : "child",
- target_pid_to_str (inferior_ptid));
-}
+ pid_t pid = ptid_get_pid (inferior_ptid);
+ int status;
-static void
-inf_ptrace_open (char *arg, int from_tty)
-{
- error ("Use the \"run\" command to start a Unix child process.");
-}
+ if (pid == 0)
+ return;
-/* Stub function which causes the inferior that runs it, to be ptrace-able
- by its parent process. */
+ ptrace (PT_KILL, pid, (PTRACE_TYPE_ARG3)0, 0);
+ waitpid (pid, &status, 0);
-static void
-inf_ptrace_me (void)
-{
- /* "Trace me, Dr. Memory!" */
- ptrace (0, 0, (PTRACE_TYPE_ARG3) 0, 0);
+ target_mourn_inferior ();
}
-/* Stub function which causes the GDB that runs it, to start ptrace-ing
- the child process. */
+/* Stop the inferior. */
static void
-inf_ptrace_him (int pid)
+inf_ptrace_stop (ptid_t ptid)
{
- push_target (ptrace_ops_hack);
-
- /* On some targets, there must be some explicit synchronization
- between the parent and child processes after the debugger
- forks, and before the child execs the debuggee program. This
- call basically gives permission for the child to exec.
- */
-
- target_acknowledge_created_inferior (pid);
-
- /* START_INFERIOR_TRAPS_EXPECTED is defined in inferior.h,
- * and will be 1 or 2 depending on whether we're starting
- * without or with a shell.
- */
- startup_inferior (START_INFERIOR_TRAPS_EXPECTED);
-
- /* On some targets, there must be some explicit actions taken after
- the inferior has been started up.
- */
- target_post_startup_inferior (pid_to_ptid (pid));
+ /* Send a SIGINT to the process group. This acts just like the user
+ typed a ^C on the controlling terminal. Note that using a
+ negative process number in kill() is a System V-ism. The proper
+ BSD interface is killpg(). However, all modern BSDs support the
+ System V interface too. */
+ kill (-inferior_process_group (), SIGINT);
}
-/* Start an inferior Unix child process and sets inferior_ptid to its
- pid. EXEC_FILE is the file to run. ALLARGS is a string containing
- the arguments to the program. ENV is the environment vector to
- pass. Errors reported with error(). */
+/* Resume execution of thread PTID, or all threads if PTID is -1. If
+ STEP is nonzero, single-step it. If SIGNAL is nonzero, give it
+ that signal. */
static void
-inf_ptrace_create_inferior (char *exec_file, char *allargs, char **env,
- int from_tty)
+inf_ptrace_resume (struct target_ops *ops,
+ ptid_t ptid, int step, enum target_signal signal)
{
- fork_inferior (exec_file, allargs, env, inf_ptrace_me, inf_ptrace_him,
- NULL, NULL);
- /* We are at the first instruction we care about. */
- observer_notify_inferior_created (¤t_target, from_tty);
- /* Pedal to the metal... */
- proceed ((CORE_ADDR) -1, TARGET_SIGNAL_0, 0);
-}
+ pid_t pid = ptid_get_pid (ptid);
+ int request = PT_CONTINUE;
-static void
-inf_ptrace_post_startup_inferior (ptid_t ptid)
-{
- /* This version of Unix doesn't require a meaningful "post startup inferior"
- operation by a debugger.
- */
-}
+ if (pid == -1)
+ /* Resume all threads. Traditionally ptrace() only supports
+ single-threaded processes, so simply resume the inferior. */
+ pid = ptid_get_pid (inferior_ptid);
-static void
-inf_ptrace_acknowledge_created_inferior (int pid)
-{
- /* This version of Unix doesn't require a meaningful "acknowledge created inferior"
- operation by a debugger.
- */
-}
+ if (step)
+ {
+ /* If this system does not support PT_STEP, a higher level
+ function will have called single_step() to transmute the step
+ request into a continue request (by setting breakpoints on
+ all possible successor instructions), so we don't have to
+ worry about that here. */
+ request = PT_STEP;
+ }
-static int
-inf_ptrace_insert_fork_catchpoint (int pid)
-{
- /* This version of Unix doesn't support notification of fork events. */
- return 0;
+ /* An address of (PTRACE_TYPE_ARG3)1 tells ptrace to continue from
+ where it was. If GDB wanted it to start some other way, we have
+ already written a new program counter value to the child. */
+ errno = 0;
+ ptrace (request, pid, (PTRACE_TYPE_ARG3)1, target_signal_to_host (signal));
+ if (errno != 0)
+ perror_with_name (("ptrace"));
}
-static int
-inf_ptrace_remove_fork_catchpoint (int pid)
-{
- /* This version of Unix doesn't support notification of fork events. */
- return 0;
-}
+/* Wait for the child specified by PTID to do something. Return the
+ process ID of the child, or MINUS_ONE_PTID in case of error; store
+ the status in *OURSTATUS. */
-static int
-inf_ptrace_insert_vfork_catchpoint (int pid)
+static ptid_t
+inf_ptrace_wait (struct target_ops *ops,
+ ptid_t ptid, struct target_waitstatus *ourstatus, int options)
{
- /* This version of Unix doesn't support notification of vfork events. */
- return 0;
-}
+ pid_t pid;
+ int status, save_errno;
-static int
-inf_ptrace_remove_vfork_catchpoint (int pid)
-{
- /* This version of Unix doesn't support notification of vfork events. */
- return 0;
-}
+ do
+ {
+ set_sigint_trap ();
-static int
-inf_ptrace_follow_fork (int follow_child)
-{
- /* This version of Unix doesn't support following fork or vfork events. */
- return 0;
-}
+ do
+ {
+ pid = waitpid (ptid_get_pid (ptid), &status, 0);
+ save_errno = errno;
+ }
+ while (pid == -1 && errno == EINTR);
-static int
-inf_ptrace_insert_exec_catchpoint (int pid)
-{
- /* This version of Unix doesn't support notification of exec events. */
- return 0;
-}
+ clear_sigint_trap ();
-static int
-inf_ptrace_remove_exec_catchpoint (int pid)
-{
- /* This version of Unix doesn't support notification of exec events. */
- return 0;
-}
+ if (pid == -1)
+ {
+ fprintf_unfiltered (gdb_stderr,
+ _("Child process unexpectedly missing: %s.\n"),
+ safe_strerror (save_errno));
-static int
-inf_ptrace_reported_exec_events_per_exec_call (void)
-{
- /* This version of Unix doesn't support notification of exec events.
- */
- return 1;
-}
+ /* Claim it exited with unknown signal. */
+ ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
+ ourstatus->value.sig = TARGET_SIGNAL_UNKNOWN;
+ return inferior_ptid;
+ }
-static int
-inf_ptrace_has_exited (int pid, int wait_status, int *exit_status)
-{
- if (WIFEXITED (wait_status))
- {
- *exit_status = WEXITSTATUS (wait_status);
- return 1;
+ /* Ignore terminated detached child processes. */
+ if (!WIFSTOPPED (status) && pid != ptid_get_pid (inferior_ptid))
+ pid = -1;
}
+ while (pid == -1);
- if (WIFSIGNALED (wait_status))
+#ifdef PT_GET_PROCESS_STATE
+ if (WIFSTOPPED (status))
{
- *exit_status = 0; /* ?? Don't know what else to say here. */
- return 1;
- }
+ ptrace_state_t pe;
+ pid_t fpid;
- /* ?? Do we really need to consult the event state, too? Assume the
- wait_state alone suffices.
- */
- return 0;
-}
-
-static void
-inf_ptrace_mourn_inferior (void)
-{
- unpush_target (ptrace_ops_hack);
- generic_mourn_inferior ();
-}
+ if (ptrace (PT_GET_PROCESS_STATE, pid,
+ (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1)
+ perror_with_name (("ptrace"));
-static int
-inf_ptrace_can_run (void)
-{
- return 1;
-}
-
-/* Send a SIGINT to the process group. This acts just like the user
- typed a ^C on the controlling terminal.
+ switch (pe.pe_report_event)
+ {
+ case PTRACE_FORK:
+ ourstatus->kind = TARGET_WAITKIND_FORKED;
+ ourstatus->value.related_pid = pid_to_ptid (pe.pe_other_pid);
+
+ /* Make sure the other end of the fork is stopped too. */
+ fpid = waitpid (pe.pe_other_pid, &status, 0);
+ if (fpid == -1)
+ perror_with_name (("waitpid"));
+
+ if (ptrace (PT_GET_PROCESS_STATE, fpid,
+ (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1)
+ perror_with_name (("ptrace"));
+
+ gdb_assert (pe.pe_report_event == PTRACE_FORK);
+ gdb_assert (pe.pe_other_pid == pid);
+ if (fpid == ptid_get_pid (inferior_ptid))
+ {
+ ourstatus->value.related_pid = pid_to_ptid (pe.pe_other_pid);
+ return pid_to_ptid (fpid);
+ }
- XXX - This may not be correct for all systems. Some may want to
- use killpg() instead of kill (-pgrp). */
+ return pid_to_ptid (pid);
+ }
+ }
+#endif
-static void
-inf_ptrace_stop (void)
-{
- kill (-inferior_process_group, SIGINT);
+ store_waitstatus (ourstatus, status);
+ return pid_to_ptid (pid);
}
-/* Perform a partial transfer to/from the specified object. For
- memory transfers, fall back to the old memory xfer functions. */
+/* Attempt a transfer all LEN bytes starting at OFFSET between the
+ inferior's OBJECT:ANNEX space and GDB's READBUF/WRITEBUF buffer.
+ Return the number of bytes actually transferred. */
static LONGEST
inf_ptrace_xfer_partial (struct target_ops *ops, enum target_object object,
- const char *annex, void *readbuf,
- const void *writebuf, ULONGEST offset, LONGEST len)
+ const char *annex, gdb_byte *readbuf,
+ const gdb_byte *writebuf,
+ ULONGEST offset, LONGEST len)
{
+ pid_t pid = ptid_get_pid (inferior_ptid);
+
switch (object)
{
case TARGET_OBJECT_MEMORY:
- if (readbuf)
- return inf_ptrace_xfer_memory (offset, readbuf, len, 0 /*write */ ,
- NULL, ops);
- if (writebuf)
- return inf_ptrace_xfer_memory (offset, readbuf, len, 1 /*write */ ,
- NULL, ops);
- return -1;
+#ifdef PT_IO
+ /* OpenBSD 3.1, NetBSD 1.6 and FreeBSD 5.0 have a new PT_IO
+ request that promises to be much more efficient in reading
+ and writing data in the traced process's address space. */
+ {
+ struct ptrace_io_desc piod;
+
+ /* NOTE: We assume that there are no distinct address spaces
+ for instruction and data. However, on OpenBSD 3.9 and
+ later, PIOD_WRITE_D doesn't allow changing memory that's
+ mapped read-only. Since most code segments will be
+ read-only, using PIOD_WRITE_D will prevent us from
+ inserting breakpoints, so we use PIOD_WRITE_I instead. */
+ piod.piod_op = writebuf ? PIOD_WRITE_I : PIOD_READ_D;
+ piod.piod_addr = writebuf ? (void *) writebuf : readbuf;
+ piod.piod_offs = (void *) (long) offset;
+ piod.piod_len = len;
+
+ errno = 0;
+ if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0)
+ /* Return the actual number of bytes read or written. */
+ return piod.piod_len;
+ /* If the PT_IO request is somehow not supported, fallback on
+ using PT_WRITE_D/PT_READ_D. Otherwise we will return zero
+ to indicate failure. */
+ if (errno != EINVAL)
+ return 0;
+ }
+#endif
+ {
+ union
+ {
+ PTRACE_TYPE_RET word;
+ gdb_byte byte[sizeof (PTRACE_TYPE_RET)];
+ } buffer;
+ ULONGEST rounded_offset;
+ LONGEST partial_len;
+
+ /* Round the start offset down to the next long word
+ boundary. */
+ rounded_offset = offset & -(ULONGEST) sizeof (PTRACE_TYPE_RET);
+
+ /* Since ptrace will transfer a single word starting at that
+ rounded_offset the partial_len needs to be adjusted down to
+ that (remember this function only does a single transfer).
+ Should the required length be even less, adjust it down
+ again. */
+ partial_len = (rounded_offset + sizeof (PTRACE_TYPE_RET)) - offset;
+ if (partial_len > len)
+ partial_len = len;
+
+ if (writebuf)
+ {
+ /* If OFFSET:PARTIAL_LEN is smaller than
+ ROUNDED_OFFSET:WORDSIZE then a read/modify write will
+ be needed. Read in the entire word. */
+ if (rounded_offset < offset
+ || (offset + partial_len
+ < rounded_offset + sizeof (PTRACE_TYPE_RET)))
+ /* Need part of initial word -- fetch it. */
+ buffer.word = ptrace (PT_READ_I, pid,
+ (PTRACE_TYPE_ARG3)(uintptr_t)
+ rounded_offset, 0);
+
+ /* Copy data to be written over corresponding part of
+ buffer. */
+ memcpy (buffer.byte + (offset - rounded_offset),
+ writebuf, partial_len);
+
+ errno = 0;
+ ptrace (PT_WRITE_D, pid,
+ (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset,
+ buffer.word);
+ if (errno)
+ {
+ /* Using the appropriate one (I or D) is necessary for
+ Gould NP1, at least. */
+ errno = 0;
+ ptrace (PT_WRITE_I, pid,
+ (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset,
+ buffer.word);
+ if (errno)
+ return 0;
+ }
+ }
+
+ if (readbuf)
+ {
+ errno = 0;
+ buffer.word = ptrace (PT_READ_I, pid,
+ (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset,
+ 0);
+ if (errno)
+ return 0;
+ /* Copy appropriate bytes out of the buffer. */
+ memcpy (readbuf, buffer.byte + (offset - rounded_offset),
+ partial_len);
+ }
+
+ return partial_len;
+ }
case TARGET_OBJECT_UNWIND_TABLE:
return -1;
}
}
+/* Return non-zero if the thread specified by PTID is alive. */
+
+static int
+inf_ptrace_thread_alive (struct target_ops *ops, ptid_t ptid)
+{
+ /* ??? Is kill the right way to do this? */
+ return (kill (ptid_get_pid (ptid), 0) != -1);
+}
+
+/* Print status information about what we're accessing. */
+
+static void
+inf_ptrace_files_info (struct target_ops *ignore)
+{
+ struct inferior *inf = current_inferior ();
+
+ printf_filtered (_("\tUsing the running image of %s %s.\n"),
+ inf->attach_flag ? "attached" : "child",
+ target_pid_to_str (inferior_ptid));
+}
+
static char *
-inf_ptrace_pid_to_str (ptid_t ptid)
+inf_ptrace_pid_to_str (struct target_ops *ops, ptid_t ptid)
{
return normal_pid_to_str (ptid);
}
+/* Create a prototype ptrace target. The client can override it with
+ local methods. */
+
struct target_ops *
inf_ptrace_target (void)
{
struct target_ops *t = inf_child_target ();
- t->to_open = inf_ptrace_open;
+
t->to_attach = inf_ptrace_attach;
- t->to_post_attach = inf_ptrace_post_attach;
t->to_detach = inf_ptrace_detach;
t->to_resume = inf_ptrace_resume;
t->to_wait = inf_ptrace_wait;
- t->to_post_wait = inf_ptrace_post_wait;
- t->to_prepare_to_store = inf_ptrace_prepare_to_store;
- t->to_xfer_memory = inf_ptrace_xfer_memory;
- t->to_xfer_partial = inf_ptrace_xfer_partial;
t->to_files_info = inf_ptrace_files_info;
- t->to_kill = inf_ptrace_kill_inferior;
+ t->to_kill = inf_ptrace_kill;
t->to_create_inferior = inf_ptrace_create_inferior;
- t->to_post_startup_inferior = inf_ptrace_post_startup_inferior;
- t->to_acknowledge_created_inferior =
- inf_ptrace_acknowledge_created_inferior;
- t->to_insert_fork_catchpoint = inf_ptrace_insert_fork_catchpoint;
- t->to_remove_fork_catchpoint = inf_ptrace_remove_fork_catchpoint;
- t->to_insert_vfork_catchpoint = inf_ptrace_insert_vfork_catchpoint;
- t->to_remove_vfork_catchpoint = inf_ptrace_remove_vfork_catchpoint;
+#ifdef PT_GET_PROCESS_STATE
t->to_follow_fork = inf_ptrace_follow_fork;
- t->to_insert_exec_catchpoint = inf_ptrace_insert_exec_catchpoint;
- t->to_remove_exec_catchpoint = inf_ptrace_remove_exec_catchpoint;
- t->to_reported_exec_events_per_exec_call =
- inf_ptrace_reported_exec_events_per_exec_call;
- t->to_has_exited = inf_ptrace_has_exited;
+ t->to_post_startup_inferior = inf_ptrace_post_startup_inferior;
+ t->to_post_attach = inf_ptrace_post_attach;
+#endif
t->to_mourn_inferior = inf_ptrace_mourn_inferior;
- t->to_can_run = inf_ptrace_can_run;
t->to_thread_alive = inf_ptrace_thread_alive;
t->to_pid_to_str = inf_ptrace_pid_to_str;
t->to_stop = inf_ptrace_stop;
- t->to_stratum = process_stratum;
- t->to_has_all_memory = 1;
- t->to_has_memory = 1;
- t->to_has_stack = 1;
- t->to_has_registers = 1;
- t->to_has_execution = 1;
- t->to_magic = OPS_MAGIC;
- ptrace_ops_hack = t;
+ t->to_xfer_partial = inf_ptrace_xfer_partial;
+
+ return t;
+}
+\f
+
+/* Pointer to a function that returns the offset within the user area
+ where a particular register is stored. */
+static CORE_ADDR (*inf_ptrace_register_u_offset)(struct gdbarch *, int, int);
+
+/* Fetch register REGNUM from the inferior. */
+
+static void
+inf_ptrace_fetch_register (struct regcache *regcache, int regnum)
+{
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ CORE_ADDR addr;
+ size_t size;
+ PTRACE_TYPE_RET *buf;
+ int pid, i;
+
+ /* This isn't really an address, but ptrace thinks of it as one. */
+ addr = inf_ptrace_register_u_offset (gdbarch, regnum, 0);
+ if (addr == (CORE_ADDR)-1
+ || gdbarch_cannot_fetch_register (gdbarch, regnum))
+ {
+ regcache_raw_supply (regcache, regnum, NULL);
+ return;
+ }
+
+ /* Cater for systems like GNU/Linux, that implement threads as
+ separate processes. */
+ pid = ptid_get_lwp (inferior_ptid);
+ if (pid == 0)
+ pid = ptid_get_pid (inferior_ptid);
+
+ size = register_size (gdbarch, regnum);
+ gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0);
+ buf = alloca (size);
+
+ /* Read the register contents from the inferior a chunk at a time. */
+ for (i = 0; i < size / sizeof (PTRACE_TYPE_RET); i++)
+ {
+ errno = 0;
+ buf[i] = ptrace (PT_READ_U, pid, (PTRACE_TYPE_ARG3)(uintptr_t)addr, 0);
+ if (errno != 0)
+ error (_("Couldn't read register %s (#%d): %s."),
+ gdbarch_register_name (gdbarch, regnum),
+ regnum, safe_strerror (errno));
+
+ addr += sizeof (PTRACE_TYPE_RET);
+ }
+ regcache_raw_supply (regcache, regnum, buf);
+}
+
+/* Fetch register REGNUM from the inferior. If REGNUM is -1, do this
+ for all registers. */
+
+static void
+inf_ptrace_fetch_registers (struct target_ops *ops,
+ struct regcache *regcache, int regnum)
+{
+ if (regnum == -1)
+ for (regnum = 0;
+ regnum < gdbarch_num_regs (get_regcache_arch (regcache));
+ regnum++)
+ inf_ptrace_fetch_register (regcache, regnum);
+ else
+ inf_ptrace_fetch_register (regcache, regnum);
+}
+
+/* Store register REGNUM into the inferior. */
+
+static void
+inf_ptrace_store_register (const struct regcache *regcache, int regnum)
+{
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ CORE_ADDR addr;
+ size_t size;
+ PTRACE_TYPE_RET *buf;
+ int pid, i;
+
+ /* This isn't really an address, but ptrace thinks of it as one. */
+ addr = inf_ptrace_register_u_offset (gdbarch, regnum, 1);
+ if (addr == (CORE_ADDR)-1
+ || gdbarch_cannot_store_register (gdbarch, regnum))
+ return;
+
+ /* Cater for systems like GNU/Linux, that implement threads as
+ separate processes. */
+ pid = ptid_get_lwp (inferior_ptid);
+ if (pid == 0)
+ pid = ptid_get_pid (inferior_ptid);
+
+ size = register_size (gdbarch, regnum);
+ gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0);
+ buf = alloca (size);
+
+ /* Write the register contents into the inferior a chunk at a time. */
+ regcache_raw_collect (regcache, regnum, buf);
+ for (i = 0; i < size / sizeof (PTRACE_TYPE_RET); i++)
+ {
+ errno = 0;
+ ptrace (PT_WRITE_U, pid, (PTRACE_TYPE_ARG3)(uintptr_t)addr, buf[i]);
+ if (errno != 0)
+ error (_("Couldn't write register %s (#%d): %s."),
+ gdbarch_register_name (gdbarch, regnum),
+ regnum, safe_strerror (errno));
+
+ addr += sizeof (PTRACE_TYPE_RET);
+ }
+}
+
+/* Store register REGNUM back into the inferior. If REGNUM is -1, do
+ this for all registers. */
+
+static void
+inf_ptrace_store_registers (struct target_ops *ops,
+ struct regcache *regcache, int regnum)
+{
+ if (regnum == -1)
+ for (regnum = 0;
+ regnum < gdbarch_num_regs (get_regcache_arch (regcache));
+ regnum++)
+ inf_ptrace_store_register (regcache, regnum);
+ else
+ inf_ptrace_store_register (regcache, regnum);
+}
+
+/* Create a "traditional" ptrace target. REGISTER_U_OFFSET should be
+ a function returning the offset within the user area where a
+ particular register is stored. */
+
+struct target_ops *
+inf_ptrace_trad_target (CORE_ADDR (*register_u_offset)
+ (struct gdbarch *, int, int))
+{
+ struct target_ops *t = inf_ptrace_target();
+
+ gdb_assert (register_u_offset);
+ inf_ptrace_register_u_offset = register_u_offset;
+ t->to_fetch_registers = inf_ptrace_fetch_registers;
+ t->to_store_registers = inf_ptrace_store_registers;
+
return t;
}
projects / deliverable / binutils-gdb.git / blobdiff