/* Low-level child interface to ptrace.
- Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998,
- 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007
- Free Software Foundation, Inc.
+ Copyright (C) 1988-2014 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., 51 Franklin Street, Fifth Floor,
- Boston, MA 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "command.h"
#include "inferior.h"
#include "inflow.h"
+#include "terminal.h"
#include "gdbcore.h"
#include "regcache.h"
-#include "gdb_stdint.h"
#include "gdb_assert.h"
-#include "gdb_string.h"
+#include <string.h>
#include "gdb_ptrace.h"
#include "gdb_wait.h"
#include <signal.h>
+#include "inf-ptrace.h"
#include "inf-child.h"
+#include "gdbthread.h"
-/* HACK: Save the ptrace ops returned by inf_ptrace_target. */
-static struct target_ops *ptrace_ops_hack;
\f
#ifdef PT_GET_PROCESS_STATE
static int
-inf_ptrace_follow_fork (struct target_ops *ops, int follow_child)
+inf_ptrace_follow_fork (struct target_ops *ops, int follow_child,
+ int detach_fork)
{
pid_t pid, fpid;
ptrace_state_t pe;
- /* FIXME: kettenis/20050720: This stuff should really be passed as
- an argument by our caller. */
- {
- ptid_t ptid;
- struct target_waitstatus status;
-
- get_last_target_status (&ptid, &status);
- gdb_assert (status.kind == TARGET_WAITKIND_FORKED);
-
- pid = ptid_get_pid (ptid);
- }
+ pid = ptid_get_pid (inferior_ptid);
if (ptrace (PT_GET_PROCESS_STATE, pid,
(PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1)
if (follow_child)
{
- inferior_ptid = pid_to_ptid (fpid);
- detach_breakpoints (pid);
+ struct inferior *parent_inf, *child_inf;
+ struct thread_info *tp;
+
+ parent_inf = find_inferior_pid (pid);
+
+ /* Add the child. */
+ child_inf = add_inferior (fpid);
+ child_inf->attach_flag = parent_inf->attach_flag;
+ copy_terminal_info (child_inf, parent_inf);
+ child_inf->pspace = parent_inf->pspace;
+ child_inf->aspace = parent_inf->aspace;
- /* Reset breakpoints in the child as appropriate. */
- follow_inferior_reset_breakpoints ();
+ /* Before detaching from the parent, remove all breakpoints from
+ it. */
+ remove_breakpoints ();
if (ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, 0) == -1)
perror_with_name (("ptrace"));
+
+ /* Switch inferior_ptid out of the parent's way. */
+ inferior_ptid = pid_to_ptid (fpid);
+
+ /* Delete the parent. */
+ detach_inferior (pid);
+
+ add_thread_silent (inferior_ptid);
}
else
{
- inferior_ptid = pid_to_ptid (pid);
- detach_breakpoints (fpid);
+ /* Breakpoints have already been detached from the child by
+ infrun.c. */
if (ptrace (PT_DETACH, fpid, (PTRACE_TYPE_ARG3)1, 0) == -1)
perror_with_name (("ptrace"));
ptrace (PT_TRACE_ME, 0, (PTRACE_TYPE_ARG3)0, 0);
}
-/* Start tracing PID. */
+/* 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 void
-inf_ptrace_him (int pid)
+inf_ptrace_create_inferior (struct target_ops *ops,
+ char *exec_file, char *allargs, char **env,
+ int from_tty)
{
- push_target (ptrace_ops_hack);
+ int pid;
+
+ /* Do not change either targets above or the same target if already present.
+ The reason is the target stack is shared across multiple inferiors. */
+ int ops_already_pushed = target_is_pushed (ops);
+ struct cleanup *back_to = make_cleanup (null_cleanup, NULL);
- /* 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. */
+ if (! ops_already_pushed)
+ {
+ /* Clear possible core file with its process_stratum. */
+ push_target (ops);
+ make_cleanup_unpush_target (ops);
+ }
- target_acknowledge_created_inferior (pid);
+ pid = fork_inferior (exec_file, allargs, env, inf_ptrace_me, NULL,
+ NULL, NULL, NULL);
+
+ discard_cleanups (back_to);
- /* 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
target_post_startup_inferior (pid_to_ptid (pid));
}
-/* 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 void
-inf_ptrace_create_inferior (char *exec_file, char *allargs, char **env,
- int from_tty)
-{
- fork_inferior (exec_file, allargs, env, inf_ptrace_me, inf_ptrace_him,
- NULL, NULL);
-}
-
#ifdef PT_GET_PROCESS_STATE
static void
/* Clean up a rotting corpse of an inferior after it died. */
static void
-inf_ptrace_mourn_inferior (void)
+inf_ptrace_mourn_inferior (struct target_ops *ops)
{
int status;
only report its exit status to its original parent. */
waitpid (ptid_get_pid (inferior_ptid), &status, 0);
- unpush_target (ptrace_ops_hack);
generic_mourn_inferior ();
+
+ if (!have_inferiors ())
+ unpush_target (ops);
}
/* 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;
pid_t pid;
- char *dummy;
+ struct inferior *inf;
- if (!args)
- error_no_arg (_("process-id to attach"));
+ /* Do not change either targets above or the same target if already present.
+ The reason is the target stack is shared across multiple inferiors. */
+ int ops_already_pushed = target_is_pushed (ops);
+ struct cleanup *back_to = make_cleanup (null_cleanup, NULL);
- 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."), args);
+ pid = parse_pid_to_attach (args);
if (pid == getpid ()) /* Trying to masturbate? */
error (_("I refuse to debug myself!"));
+ if (! ops_already_pushed)
+ {
+ /* target_pid_to_str already uses the target. Also clear possible core
+ file with its process_stratum. */
+ push_target (ops);
+ make_cleanup_unpush_target (ops);
+ }
+
if (from_tty)
{
exec_file = get_exec_file (0);
ptrace (PT_ATTACH, pid, (PTRACE_TYPE_ARG3)0, 0);
if (errno != 0)
perror_with_name (("ptrace"));
- attach_flag = 1;
#else
error (_("This system does not support attaching to a process"));
#endif
+ inf = current_inferior ();
+ inferior_appeared (inf, pid);
+ inf->attach_flag = 1;
inferior_ptid = pid_to_ptid (pid);
- push_target (ptrace_ops_hack);
+
+ /* 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);
+
+ discard_cleanups (back_to);
}
#ifdef PT_GET_PROCESS_STATE
-void
+static void
inf_ptrace_post_attach (int pid)
{
ptrace_event_t pe;
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, const char *args, int from_tty)
{
pid_t pid = ptid_get_pid (inferior_ptid);
int sig = 0;
ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, sig);
if (errno != 0)
perror_with_name (("ptrace"));
- attach_flag = 0;
#else
error (_("This system does not support detaching from a process"));
#endif
inferior_ptid = null_ptid;
- unpush_target (ptrace_ops_hack);
+ detach_inferior (pid);
+
+ if (!have_inferiors ())
+ unpush_target (ops);
}
/* Kill the inferior. */
static void
-inf_ptrace_kill (void)
+inf_ptrace_kill (struct target_ops *ops)
{
pid_t pid = ptid_get_pid (inferior_ptid);
int status;
/* Stop the inferior. */
static void
-inf_ptrace_stop (void)
+inf_ptrace_stop (ptid_t ptid)
{
/* 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);
+ kill (-inferior_process_group (), SIGINT);
}
/* Resume execution of thread PTID, or all threads if PTID is -1. If
that signal. */
static void
-inf_ptrace_resume (ptid_t ptid, int step, enum target_signal signal)
+inf_ptrace_resume (struct target_ops *ops,
+ ptid_t ptid, int step, enum gdb_signal signal)
{
pid_t pid = ptid_get_pid (ptid);
- int request = PT_CONTINUE;
+ int request;
if (pid == -1)
/* Resume all threads. Traditionally ptrace() only supports
single-threaded processes, so simply resume the inferior. */
pid = ptid_get_pid (inferior_ptid);
+ if (catch_syscall_enabled () > 0)
+ request = PT_SYSCALL;
+ else
+ request = PT_CONTINUE;
+
if (step)
{
/* If this system does not support PT_STEP, a higher level
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));
+ ptrace (request, pid, (PTRACE_TYPE_ARG3)1, gdb_signal_to_host (signal));
if (errno != 0)
perror_with_name (("ptrace"));
}
the status in *OURSTATUS. */
static ptid_t
-inf_ptrace_wait (ptid_t ptid, struct target_waitstatus *ourstatus)
+inf_ptrace_wait (struct target_ops *ops,
+ ptid_t ptid, struct target_waitstatus *ourstatus, int options)
{
pid_t pid;
int status, save_errno;
do
{
set_sigint_trap ();
- set_sigio_trap ();
do
{
}
while (pid == -1 && errno == EINTR);
- clear_sigio_trap ();
clear_sigint_trap ();
if (pid == -1)
/* Claim it exited with unknown signal. */
ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
- ourstatus->value.sig = TARGET_SIGNAL_UNKNOWN;
- return minus_one_ptid;
+ ourstatus->value.sig = GDB_SIGNAL_UNKNOWN;
+ return inferior_ptid;
}
/* Ignore terminated detached child processes. */
{
case PTRACE_FORK:
ourstatus->kind = TARGET_WAITKIND_FORKED;
- ourstatus->value.related_pid = pe.pe_other_pid;
+ 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);
gdb_assert (pe.pe_other_pid == pid);
if (fpid == ptid_get_pid (inferior_ptid))
{
- ourstatus->value.related_pid = pe.pe_other_pid;
+ ourstatus->value.related_pid = pid_to_ptid (pe.pe_other_pid);
return pid_to_ptid (fpid);
}
inf_ptrace_xfer_partial (struct target_ops *ops, enum target_object object,
const char *annex, gdb_byte *readbuf,
const gdb_byte *writebuf,
- ULONGEST offset, LONGEST len)
+ ULONGEST offset, ULONGEST len)
{
pid_t pid = ptid_get_pid (inferior_ptid);
return -1;
case TARGET_OBJECT_AUXV:
+#if defined (PT_IO) && defined (PIOD_READ_AUXV)
+ /* OpenBSD 4.5 has a new PIOD_READ_AUXV operation for the PT_IO
+ request that allows us to read the auxilliary vector. Other
+ BSD's may follow if they feel the need to support PIE. */
+ {
+ struct ptrace_io_desc piod;
+
+ if (writebuf)
+ return -1;
+ piod.piod_op = PIOD_READ_AUXV;
+ piod.piod_addr = 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;
+ }
+#endif
return -1;
case TARGET_OBJECT_WCOOKIE:
/* Return non-zero if the thread specified by PTID is alive. */
static int
-inf_ptrace_thread_alive (ptid_t ptid)
+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);
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"),
- attach_flag ? "attached" : "child",
+ inf->attach_flag ? "attached" : "child",
target_pid_to_str (inferior_ptid));
}
+static char *
+inf_ptrace_pid_to_str (struct target_ops *ops, ptid_t ptid)
+{
+ return normal_pid_to_str (ptid);
+}
+
+#if defined (PT_IO) && defined (PIOD_READ_AUXV)
+
+/* Read one auxv entry from *READPTR, not reading locations >= ENDPTR.
+ Return 0 if *READPTR is already at the end of the buffer.
+ Return -1 if there is insufficient buffer for a whole entry.
+ Return 1 if an entry was read into *TYPEP and *VALP. */
+
+static int
+inf_ptrace_auxv_parse (struct target_ops *ops, gdb_byte **readptr,
+ gdb_byte *endptr, CORE_ADDR *typep, CORE_ADDR *valp)
+{
+ struct type *int_type = builtin_type (target_gdbarch ())->builtin_int;
+ struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr;
+ const int sizeof_auxv_type = TYPE_LENGTH (int_type);
+ const int sizeof_auxv_val = TYPE_LENGTH (ptr_type);
+ enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ());
+ gdb_byte *ptr = *readptr;
+
+ if (endptr == ptr)
+ return 0;
+
+ if (endptr - ptr < 2 * sizeof_auxv_val)
+ return -1;
+
+ *typep = extract_unsigned_integer (ptr, sizeof_auxv_type, byte_order);
+ ptr += sizeof_auxv_val; /* Alignment. */
+ *valp = extract_unsigned_integer (ptr, sizeof_auxv_val, byte_order);
+ ptr += sizeof_auxv_val;
+
+ *readptr = ptr;
+ return 1;
+}
+
+#endif
+
/* Create a prototype ptrace target. The client can override it with
local methods. */
#endif
t->to_mourn_inferior = inf_ptrace_mourn_inferior;
t->to_thread_alive = inf_ptrace_thread_alive;
- t->to_pid_to_str = normal_pid_to_str;
+ t->to_pid_to_str = inf_ptrace_pid_to_str;
t->to_stop = inf_ptrace_stop;
t->to_xfer_partial = inf_ptrace_xfer_partial;
+#if defined (PT_IO) && defined (PIOD_READ_AUXV)
+ t->to_auxv_parse = inf_ptrace_auxv_parse;
+#endif
- ptrace_ops_hack = t;
return t;
}
\f
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 (current_gdbarch, regnum, 0);
+ addr = inf_ptrace_register_u_offset (gdbarch, regnum, 0);
if (addr == (CORE_ADDR)-1
- || gdbarch_cannot_fetch_register (current_gdbarch, regnum))
+ || gdbarch_cannot_fetch_register (gdbarch, regnum))
{
regcache_raw_supply (regcache, regnum, NULL);
return;
if (pid == 0)
pid = ptid_get_pid (inferior_ptid);
- size = register_size (current_gdbarch, regnum);
+ size = register_size (gdbarch, regnum);
gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0);
buf = alloca (size);
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."),
- REGISTER_NAME (regnum), regnum, safe_strerror (errno));
+ gdbarch_register_name (gdbarch, regnum),
+ regnum, safe_strerror (errno));
addr += sizeof (PTRACE_TYPE_RET);
}
for all registers. */
static void
-inf_ptrace_fetch_registers (struct regcache *regcache, int regnum)
+inf_ptrace_fetch_registers (struct target_ops *ops,
+ struct regcache *regcache, int regnum)
{
if (regnum == -1)
- for (regnum = 0; regnum < NUM_REGS; regnum++)
+ 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);
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 (current_gdbarch, regnum, 1);
+ addr = inf_ptrace_register_u_offset (gdbarch, regnum, 1);
if (addr == (CORE_ADDR)-1
- || gdbarch_cannot_store_register (current_gdbarch, regnum))
+ || gdbarch_cannot_store_register (gdbarch, regnum))
return;
/* Cater for systems like GNU/Linux, that implement threads as
if (pid == 0)
pid = ptid_get_pid (inferior_ptid);
- size = register_size (current_gdbarch, regnum);
+ size = register_size (gdbarch, regnum);
gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0);
buf = alloca (size);
ptrace (PT_WRITE_U, pid, (PTRACE_TYPE_ARG3)(uintptr_t)addr, buf[i]);
if (errno != 0)
error (_("Couldn't write register %s (#%d): %s."),
- REGISTER_NAME (regnum), regnum, safe_strerror (errno));
+ 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. */
-void
-inf_ptrace_store_registers (struct regcache *regcache, int regnum)
+static void
+inf_ptrace_store_registers (struct target_ops *ops,
+ struct regcache *regcache, int regnum)
{
if (regnum == -1)
- for (regnum = 0; regnum < NUM_REGS; regnum++)
+ 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);