/* Target operations for the remote server for GDB.
Copyright (C) 2002-2020 Free Software Foundation, Inc.
Contributed by MontaVista Software.
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 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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, see . */
#include "server.h"
#include "tracepoint.h"
#include "gdbsupport/byte-vector.h"
#include "hostio.h"
process_stratum_target *the_target;
int
set_desired_thread ()
{
client_state &cs = get_client_state ();
thread_info *found = find_thread_ptid (cs.general_thread);
current_thread = found;
return (current_thread != NULL);
}
/* The thread that was current before prepare_to_access_memory was
called. done_accessing_memory uses this to restore the previous
selected thread. */
static ptid_t prev_general_thread;
/* See target.h. */
int
prepare_to_access_memory (void)
{
client_state &cs = get_client_state ();
/* The first thread found. */
struct thread_info *first = NULL;
/* The first stopped thread found. */
struct thread_info *stopped = NULL;
/* The current general thread, if found. */
struct thread_info *current = NULL;
/* Save the general thread value, since prepare_to_access_memory could change
it. */
prev_general_thread = cs.general_thread;
int res = the_target->pt->prepare_to_access_memory ();
if (res != 0)
return res;
for_each_thread (prev_general_thread.pid (), [&] (thread_info *thread)
{
if (mythread_alive (thread->id))
{
if (stopped == NULL && the_target->thread_stopped != NULL
&& thread_stopped (thread))
stopped = thread;
if (first == NULL)
first = thread;
if (current == NULL && prev_general_thread == thread->id)
current = thread;
}
});
/* The thread we end up choosing. */
struct thread_info *thread;
/* Prefer a stopped thread. If none is found, try the current
thread. Otherwise, take the first thread in the process. If
none is found, undo the effects of
target->prepare_to_access_memory() and return error. */
if (stopped != NULL)
thread = stopped;
else if (current != NULL)
thread = current;
else if (first != NULL)
thread = first;
else
{
done_accessing_memory ();
return 1;
}
current_thread = thread;
cs.general_thread = ptid_of (thread);
return 0;
}
/* See target.h. */
void
done_accessing_memory (void)
{
client_state &cs = get_client_state ();
the_target->pt->done_accessing_memory ();
/* Restore the previous selected thread. */
cs.general_thread = prev_general_thread;
switch_to_thread (the_target, cs.general_thread);
}
int
read_inferior_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len)
{
int res;
res = the_target->pt->read_memory (memaddr, myaddr, len);
check_mem_read (memaddr, myaddr, len);
return res;
}
/* See target/target.h. */
int
target_read_memory (CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len)
{
return read_inferior_memory (memaddr, myaddr, len);
}
/* See target/target.h. */
int
target_read_uint32 (CORE_ADDR memaddr, uint32_t *result)
{
return read_inferior_memory (memaddr, (gdb_byte *) result, sizeof (*result));
}
/* See target/target.h. */
int
target_write_memory (CORE_ADDR memaddr, const unsigned char *myaddr,
ssize_t len)
{
/* Make a copy of the data because check_mem_write may need to
update it. */
gdb::byte_vector buffer (myaddr, myaddr + len);
check_mem_write (memaddr, buffer.data (), myaddr, len);
return the_target->pt->write_memory (memaddr, buffer.data (), len);
}
ptid_t
mywait (ptid_t ptid, struct target_waitstatus *ourstatus, int options,
int connected_wait)
{
ptid_t ret;
if (connected_wait)
server_waiting = 1;
ret = target_wait (ptid, ourstatus, options);
/* We don't expose _LOADED events to gdbserver core. See the
`dlls_changed' global. */
if (ourstatus->kind == TARGET_WAITKIND_LOADED)
ourstatus->kind = TARGET_WAITKIND_STOPPED;
/* If GDB is connected through TCP/serial, then GDBserver will most
probably be running on its own terminal/console, so it's nice to
print there why is GDBserver exiting. If however, GDB is
connected through stdio, then there's no need to spam the GDB
console with this -- the user will already see the exit through
regular GDB output, in that same terminal. */
if (!remote_connection_is_stdio ())
{
if (ourstatus->kind == TARGET_WAITKIND_EXITED)
fprintf (stderr,
"\nChild exited with status %d\n", ourstatus->value.integer);
else if (ourstatus->kind == TARGET_WAITKIND_SIGNALLED)
fprintf (stderr, "\nChild terminated with signal = 0x%x (%s)\n",
gdb_signal_to_host (ourstatus->value.sig),
gdb_signal_to_name (ourstatus->value.sig));
}
if (connected_wait)
server_waiting = 0;
return ret;
}
/* See target/target.h. */
void
target_stop_and_wait (ptid_t ptid)
{
struct target_waitstatus status;
bool was_non_stop = non_stop;
struct thread_resume resume_info;
resume_info.thread = ptid;
resume_info.kind = resume_stop;
resume_info.sig = GDB_SIGNAL_0;
the_target->pt->resume (&resume_info, 1);
non_stop = true;
mywait (ptid, &status, 0, 0);
non_stop = was_non_stop;
}
/* See target/target.h. */
ptid_t
target_wait (ptid_t ptid, struct target_waitstatus *status, int options)
{
return the_target->pt->wait (ptid, status, options);
}
/* See target/target.h. */
void
target_mourn_inferior (ptid_t ptid)
{
the_target->pt->mourn (find_process_pid (ptid.pid ()));
}
/* See target/target.h. */
void
target_continue_no_signal (ptid_t ptid)
{
struct thread_resume resume_info;
resume_info.thread = ptid;
resume_info.kind = resume_continue;
resume_info.sig = GDB_SIGNAL_0;
the_target->pt->resume (&resume_info, 1);
}
/* See target/target.h. */
void
target_continue (ptid_t ptid, enum gdb_signal signal)
{
struct thread_resume resume_info;
resume_info.thread = ptid;
resume_info.kind = resume_continue;
resume_info.sig = gdb_signal_to_host (signal);
the_target->pt->resume (&resume_info, 1);
}
/* See target/target.h. */
int
target_supports_multi_process (void)
{
return (the_target->supports_multi_process != NULL ?
(*the_target->supports_multi_process) () : 0);
}
int
start_non_stop (int nonstop)
{
if (the_target->start_non_stop == NULL)
{
if (nonstop)
return -1;
else
return 0;
}
return (*the_target->start_non_stop) (nonstop);
}
void
set_target_ops (process_stratum_target *target)
{
the_target = XNEW (process_stratum_target);
memcpy (the_target, target, sizeof (*the_target));
}
/* Convert pid to printable format. */
const char *
target_pid_to_str (ptid_t ptid)
{
static char buf[80];
if (ptid == minus_one_ptid)
xsnprintf (buf, sizeof (buf), "");
else if (ptid == null_ptid)
xsnprintf (buf, sizeof (buf), "");
else if (ptid.tid () != 0)
xsnprintf (buf, sizeof (buf), "Thread %d.0x%lx",
ptid.pid (), ptid.tid ());
else if (ptid.lwp () != 0)
xsnprintf (buf, sizeof (buf), "LWP %d.%ld",
ptid.pid (), ptid.lwp ());
else
xsnprintf (buf, sizeof (buf), "Process %d",
ptid.pid ());
return buf;
}
int
kill_inferior (process_info *proc)
{
gdb_agent_about_to_close (proc->pid);
return the_target->pt->kill (proc);
}
/* Default implementation for breakpoint_kind_for_pc.
The default behavior for targets that don't implement breakpoint_kind_for_pc
is to use the size of a breakpoint as the kind. */
int
default_breakpoint_kind_from_pc (CORE_ADDR *pcptr)
{
int size = 0;
gdb_assert (the_target->sw_breakpoint_from_kind != NULL);
(*the_target->sw_breakpoint_from_kind) (0, &size);
return size;
}
/* Define it. */
target_terminal_state target_terminal::m_terminal_state
= target_terminal_state::is_ours;
/* See target/target.h. */
void
target_terminal::init ()
{
/* Placeholder needed because of fork_inferior. Not necessary on
GDBserver. */
}
/* See target/target.h. */
void
target_terminal::inferior ()
{
/* Placeholder needed because of fork_inferior. Not necessary on
GDBserver. */
}
/* See target/target.h. */
void
target_terminal::ours ()
{
/* Placeholder needed because of fork_inferior. Not necessary on
GDBserver. */
}
/* See target/target.h. */
void
target_terminal::ours_for_output (void)
{
/* Placeholder. */
}
/* See target/target.h. */
void
target_terminal::info (const char *arg, int from_tty)
{
/* Placeholder. */
}
/* Default implementations of target ops.
See target.h for definitions. */
void
process_target::post_create_inferior ()
{
/* Nop. */
}
int
process_target::prepare_to_access_memory ()
{
return 0;
}
void
process_target::done_accessing_memory ()
{
/* Nop. */
}
void
process_target::look_up_symbols ()
{
/* Nop. */
}
bool
process_target::supports_read_auxv ()
{
return false;
}
int
process_target::read_auxv (CORE_ADDR offset, unsigned char *myaddr,
unsigned int len)
{
gdb_assert_not_reached ("target op read_auxv not supported");
}
bool
process_target::supports_z_point_type (char z_type)
{
return false;
}
int
process_target::insert_point (enum raw_bkpt_type type, CORE_ADDR addr,
int size, raw_breakpoint *bp)
{
return 1;
}
int
process_target::remove_point (enum raw_bkpt_type type, CORE_ADDR addr,
int size, raw_breakpoint *bp)
{
return 1;
}
bool
process_target::stopped_by_sw_breakpoint ()
{
return false;
}
bool
process_target::supports_stopped_by_sw_breakpoint ()
{
return false;
}
bool
process_target::stopped_by_hw_breakpoint ()
{
return false;
}
bool
process_target::supports_stopped_by_hw_breakpoint ()
{
return false;
}
bool
process_target::supports_hardware_single_step ()
{
return false;
}
bool
process_target::stopped_by_watchpoint ()
{
return false;
}
CORE_ADDR
process_target::stopped_data_address ()
{
return 0;
}
bool
process_target::supports_read_offsets ()
{
return false;
}
int
process_target::read_offsets (CORE_ADDR *text, CORE_ADDR *data)
{
gdb_assert_not_reached ("target op read_offsets not supported");
}
bool
process_target::supports_get_tls_address ()
{
return false;
}
int
process_target::get_tls_address (thread_info *thread, CORE_ADDR offset,
CORE_ADDR load_module, CORE_ADDR *address)
{
gdb_assert_not_reached ("target op get_tls_address not supported");
}
void
process_target::hostio_last_error (char *buf)
{
hostio_last_error_from_errno (buf);
}
bool
process_target::supports_qxfer_osdata ()
{
return false;
}
int
process_target::qxfer_osdata (const char *annex, unsigned char *readbuf,
unsigned const char *writebuf,
CORE_ADDR offset, int len)
{
gdb_assert_not_reached ("target op qxfer_osdata not supported");
}