/* 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, 2008, 2009
- Free Software Foundation, Inc.
+ Copyright (C) 1988-2015 Free Software Foundation, Inc.
This file is part of GDB.
#include "command.h"
#include "inferior.h"
#include "inflow.h"
+#include "terminal.h"
#include "gdbcore.h"
#include "regcache.h"
-
-#include "gdb_assert.h"
-#include "gdb_string.h"
#include "gdb_ptrace.h"
#include "gdb_wait.h"
#include <signal.h>
#ifdef PT_GET_PROCESS_STATE
+/* Target hook for follow_fork. On entry and at return inferior_ptid is
+ the ptid of the followed inferior. */
+
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;
- struct thread_info *last_tp = NULL;
-
- /* 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);
- last_tp = find_thread_pid (ptid);
- }
-
- if (ptrace (PT_GET_PROCESS_STATE, pid,
- (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1)
- perror_with_name (("ptrace"));
-
- gdb_assert (pe.pe_report_event == PTRACE_FORK);
- fpid = pe.pe_other_pid;
-
- if (follow_child)
- {
- /* 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;
- int attach_flag = find_inferior_pid (pid)->attach_flag;
- struct inferior *inf;
- struct thread_info *tp;
-
- /* Otherwise, deleting the parent would get rid of this
- breakpoint. */
- last_tp->step_resume_breakpoint = NULL;
-
- /* 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 the child. */
- inf = add_inferior (fpid);
- inf->attach_flag = attach_flag;
- tp = add_thread_silent (inferior_ptid);
-
- 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;
-
- /* Reset breakpoints in the child as appropriate. */
- follow_inferior_reset_breakpoints ();
- }
- else
+ if (!follow_child)
{
- inferior_ptid = pid_to_ptid (pid);
+ struct thread_info *tp = inferior_thread ();
+ pid_t child_pid = ptid_get_pid (tp->pending_follow.value.related_pid);
/* Breakpoints have already been detached from the child by
infrun.c. */
- if (ptrace (PT_DETACH, fpid, (PTRACE_TYPE_ARG3)1, 0) == -1)
+ if (ptrace (PT_DETACH, child_pid, (PTRACE_TYPE_ARG3)1, 0) == -1)
perror_with_name (("ptrace"));
- detach_inferior (pid);
}
return 0;
}
+static int
+inf_ptrace_insert_fork_catchpoint (struct target_ops *self, int pid)
+{
+ return 0;
+}
+
+static int
+inf_ptrace_remove_fork_catchpoint (struct target_ops *self, int pid)
+{
+ return 0;
+}
+
#endif /* PT_GET_PROCESS_STATE */
\f
{
int pid;
- pid = fork_inferior (exec_file, allargs, env, inf_ptrace_me, NULL,
- NULL, NULL);
+ /* 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);
- push_target (ops);
+ if (! ops_already_pushed)
+ {
+ /* Clear possible core file with its process_stratum. */
+ push_target (ops);
+ make_cleanup_unpush_target (ops);
+ }
- /* 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. */
+ pid = fork_inferior (exec_file, allargs, env, inf_ptrace_me, NULL,
+ NULL, NULL, NULL);
- target_acknowledge_created_inferior (pid);
+ 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
#ifdef PT_GET_PROCESS_STATE
static void
-inf_ptrace_post_startup_inferior (ptid_t pid)
+inf_ptrace_post_startup_inferior (struct target_ops *self, ptid_t pid)
{
ptrace_event_t pe;
only report its exit status to its original parent. */
waitpid (ptid_get_pid (inferior_ptid), &status, 0);
- unpush_target (ops);
- generic_mourn_inferior ();
+ inf_child_mourn_inferior (ops);
}
/* Attach to the process specified by ARGS. If FROM_TTY is non-zero,
be chatty about it. */
static void
-inf_ptrace_attach (struct target_ops *ops, char *args, int from_tty)
+inf_ptrace_attach (struct target_ops *ops, const 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);
error (_("This system does not support attaching to a process"));
#endif
- inferior_ptid = pid_to_ptid (pid);
-
- inf = add_inferior (pid);
+ inf = current_inferior ();
+ inferior_appeared (inf, pid);
inf->attach_flag = 1;
+ inferior_ptid = pid_to_ptid (pid);
/* 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);
+ discard_cleanups (back_to);
}
#ifdef PT_GET_PROCESS_STATE
-void
-inf_ptrace_post_attach (int pid)
+static void
+inf_ptrace_post_attach (struct target_ops *self, int pid)
{
ptrace_event_t pe;
specified by ARGS. If FROM_TTY is non-zero, be chatty about it. */
static void
-inf_ptrace_detach (struct target_ops *ops, 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;
inferior_ptid = null_ptid;
detach_inferior (pid);
- if (!have_inferiors ())
- unpush_target (ops);
+ inf_child_maybe_unpush_target (ops);
}
/* Kill the inferior. */
/* Stop the inferior. */
static void
-inf_ptrace_stop (ptid_t ptid)
+inf_ptrace_stop (struct target_ops *self, 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
kill (-inferior_process_group (), SIGINT);
}
+/* Return which PID to pass to ptrace in order to observe/control the
+ tracee identified by PTID. */
+
+static pid_t
+get_ptrace_pid (ptid_t ptid)
+{
+ pid_t pid;
+
+ /* If we have an LWPID to work with, use it. Otherwise, we're
+ dealing with a non-threaded program/target. */
+ pid = ptid_get_lwp (ptid);
+ if (pid == 0)
+ pid = ptid_get_pid (ptid);
+ return pid;
+}
+
/* 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_resume (struct target_ops *ops,
- ptid_t ptid, int step, enum target_signal signal)
+ ptid_t ptid, int step, enum gdb_signal signal)
{
- pid_t pid = ptid_get_pid (ptid);
- int request = PT_CONTINUE;
+ pid_t pid;
+ int request;
- if (pid == -1)
+ if (ptid_equal (minus_one_ptid, ptid))
/* Resume all threads. Traditionally ptrace() only supports
single-threaded processes, so simply resume the inferior. */
pid = ptid_get_pid (inferior_ptid);
+ else
+ pid = get_ptrace_pid (ptid);
+
+ if (catch_syscall_enabled () > 0)
+ request = PT_SYSCALL;
+ else
+ request = PT_CONTINUE;
if (step)
{
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"));
}
static ptid_t
inf_ptrace_wait (struct target_ops *ops,
- ptid_t ptid, struct target_waitstatus *ourstatus)
+ ptid_t ptid, struct target_waitstatus *ourstatus, int options)
{
pid_t pid;
int status, save_errno;
/* Claim it exited with unknown signal. */
ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
- ourstatus->value.sig = TARGET_SIGNAL_UNKNOWN;
+ ourstatus->value.sig = GDB_SIGNAL_UNKNOWN;
return inferior_ptid;
}
return pid_to_ptid (pid);
}
-/* 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. */
+/* Implement the to_xfer_partial target_ops method. */
-static LONGEST
+static enum target_xfer_status
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, ULONGEST *xfered_len)
{
pid_t pid = ptid_get_pid (inferior_ptid);
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;
+ {
+ /* Return the actual number of bytes read or written. */
+ *xfered_len = piod.piod_len;
+ return (piod.piod_len == 0) ? TARGET_XFER_EOF : TARGET_XFER_OK;
+ }
/* 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;
+ return TARGET_XFER_EOF;
}
#endif
{
gdb_byte byte[sizeof (PTRACE_TYPE_RET)];
} buffer;
ULONGEST rounded_offset;
- LONGEST partial_len;
+ ULONGEST partial_len;
/* Round the start offset down to the next long word
boundary. */
(PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset,
buffer.word);
if (errno)
- return 0;
+ return TARGET_XFER_EOF;
}
}
(PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset,
0);
if (errno)
- return 0;
+ return TARGET_XFER_EOF;
/* Copy appropriate bytes out of the buffer. */
memcpy (readbuf, buffer.byte + (offset - rounded_offset),
partial_len);
}
- return partial_len;
+ *xfered_len = partial_len;
+ return TARGET_XFER_OK;
}
case TARGET_OBJECT_UNWIND_TABLE:
- return -1;
+ return TARGET_XFER_E_IO;
case TARGET_OBJECT_AUXV:
- return -1;
+#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 TARGET_XFER_E_IO;
+ 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. */
+ *xfered_len = piod.piod_len;
+ return (piod.piod_len == 0) ? TARGET_XFER_EOF : TARGET_XFER_OK;
+ }
+ }
+#endif
+ return TARGET_XFER_E_IO;
case TARGET_OBJECT_WCOOKIE:
- return -1;
+ return TARGET_XFER_E_IO;
default:
- return -1;
+ return TARGET_XFER_E_IO;
}
}
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. */
t->to_create_inferior = inf_ptrace_create_inferior;
#ifdef PT_GET_PROCESS_STATE
t->to_follow_fork = inf_ptrace_follow_fork;
+ t->to_insert_fork_catchpoint = inf_ptrace_insert_fork_catchpoint;
+ t->to_remove_fork_catchpoint = inf_ptrace_remove_fork_catchpoint;
t->to_post_startup_inferior = inf_ptrace_post_startup_inferior;
t->to_post_attach = inf_ptrace_post_attach;
#endif
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
return t;
}
projects / binutils.git / blobdiff