binutils-gdb/gdbserver/target.cc
Tankut Baris Aktemur 8263b346fa gdbserver: do not report btrace support if target does not announce it
Gdbserver unconditionally reports support for btrace packets.  Do not
report the support, if the underlying target does not say it supports
it.  Otherwise GDB would query the server with btrace-related packets
unnecessarily.
2022-11-09 17:46:21 +01:00

833 lines
16 KiB
C++

/* Target operations for the remote server for GDB.
Copyright (C) 2002-2022 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 <http://www.gnu.org/licenses/>. */
#include "server.h"
#include "tracepoint.h"
#include "gdbsupport/byte-vector.h"
#include "hostio.h"
#include <fcntl.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
process_stratum_target *the_target;
/* See target.h. */
bool
set_desired_thread ()
{
client_state &cs = get_client_state ();
thread_info *found = find_thread_ptid (cs.general_thread);
if (found == nullptr)
{
process_info *proc = find_process_pid (cs.general_thread.pid ());
if (proc == nullptr)
{
threads_debug_printf
("did not find thread nor process for general_thread %s",
cs.general_thread.to_string ().c_str ());
}
else
{
threads_debug_printf
("did not find thread for general_thread %s, but found process",
cs.general_thread.to_string ().c_str ());
}
switch_to_process (proc);
}
else
switch_to_thread (found);
return (current_thread != NULL);
}
/* See target.h. */
bool
set_desired_process ()
{
client_state &cs = get_client_state ();
process_info *proc = find_process_pid (cs.general_thread.pid ());
if (proc == nullptr)
{
threads_debug_printf
("did not find process for general_thread %s",
cs.general_thread.to_string ().c_str ());
}
switch_to_process (proc);
return proc != nullptr;
}
int
read_inferior_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len)
{
/* At the time of writing, GDB only sends write packets with LEN==0,
not read packets (see comment in target_write_memory), but it
doesn't hurt to prevent problems if it ever does, or we're
connected to some client other than GDB that does. */
if (len == 0)
return 0;
int res = the_target->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)
{
/* GDB may send X packets with LEN==0, for probing packet support.
If we let such a request go through, then buffer.data() below may
return NULL, which may confuse target implementations. Handle it
here to avoid lower levels having to care about this case. */
if (len == 0)
return 0;
/* 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->write_memory (memaddr, buffer.data (), len);
}
ptid_t
mywait (ptid_t ptid, struct target_waitstatus *ourstatus,
target_wait_flags 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->set_stopped (GDB_SIGNAL_0);
/* 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->exit_status ());
else if (ourstatus->kind () == TARGET_WAITKIND_SIGNALLED)
fprintf (stderr, "\nChild terminated with signal = 0x%x (%s)\n",
gdb_signal_to_host (ourstatus->sig ()),
gdb_signal_to_name (ourstatus->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->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,
target_wait_flags options)
{
return the_target->wait (ptid, status, options);
}
/* See target/target.h. */
void
target_mourn_inferior (ptid_t ptid)
{
the_target->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->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->resume (&resume_info, 1);
}
/* See target/target.h. */
int
target_supports_multi_process (void)
{
return the_target->supports_multi_process ();
}
void
set_target_ops (process_stratum_target *target)
{
the_target = target;
}
/* Convert pid to printable format. */
std::string
target_pid_to_str (ptid_t ptid)
{
if (ptid == minus_one_ptid)
return string_printf("<all threads>");
else if (ptid == null_ptid)
return string_printf("<null thread>");
else if (ptid.tid () != 0)
return string_printf("Thread %d.0x%s",
ptid.pid (),
phex_nz (ptid.tid (), sizeof (ULONGEST)));
else if (ptid.lwp () != 0)
return string_printf("LWP %d.%ld",
ptid.pid (), ptid.lwp ());
else
return string_printf("Process %d",
ptid.pid ());
}
int
kill_inferior (process_info *proc)
{
gdb_agent_about_to_close (proc->pid);
return the_target->kill (proc);
}
/* 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_stratum_target::post_create_inferior ()
{
/* Nop. */
}
void
process_stratum_target::look_up_symbols ()
{
/* Nop. */
}
bool
process_stratum_target::supports_read_auxv ()
{
return false;
}
int
process_stratum_target::read_auxv (CORE_ADDR offset, unsigned char *myaddr,
unsigned int len)
{
gdb_assert_not_reached ("target op read_auxv not supported");
}
bool
process_stratum_target::supports_z_point_type (char z_type)
{
return false;
}
int
process_stratum_target::insert_point (enum raw_bkpt_type type,
CORE_ADDR addr,
int size, raw_breakpoint *bp)
{
return 1;
}
int
process_stratum_target::remove_point (enum raw_bkpt_type type,
CORE_ADDR addr,
int size, raw_breakpoint *bp)
{
return 1;
}
bool
process_stratum_target::stopped_by_sw_breakpoint ()
{
return false;
}
bool
process_stratum_target::supports_stopped_by_sw_breakpoint ()
{
return false;
}
bool
process_stratum_target::stopped_by_hw_breakpoint ()
{
return false;
}
bool
process_stratum_target::supports_stopped_by_hw_breakpoint ()
{
return false;
}
bool
process_stratum_target::supports_hardware_single_step ()
{
return false;
}
bool
process_stratum_target::stopped_by_watchpoint ()
{
return false;
}
CORE_ADDR
process_stratum_target::stopped_data_address ()
{
return 0;
}
bool
process_stratum_target::supports_read_offsets ()
{
return false;
}
bool
process_stratum_target::supports_memory_tagging ()
{
return false;
}
bool
process_stratum_target::fetch_memtags (CORE_ADDR address, size_t len,
gdb::byte_vector &tags, int type)
{
gdb_assert_not_reached ("target op fetch_memtags not supported");
}
bool
process_stratum_target::store_memtags (CORE_ADDR address, size_t len,
const gdb::byte_vector &tags, int type)
{
gdb_assert_not_reached ("target op store_memtags not supported");
}
int
process_stratum_target::read_offsets (CORE_ADDR *text, CORE_ADDR *data)
{
gdb_assert_not_reached ("target op read_offsets not supported");
}
bool
process_stratum_target::supports_get_tls_address ()
{
return false;
}
int
process_stratum_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");
}
bool
process_stratum_target::supports_qxfer_osdata ()
{
return false;
}
int
process_stratum_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");
}
bool
process_stratum_target::supports_qxfer_siginfo ()
{
return false;
}
int
process_stratum_target::qxfer_siginfo (const char *annex,
unsigned char *readbuf,
unsigned const char *writebuf,
CORE_ADDR offset, int len)
{
gdb_assert_not_reached ("target op qxfer_siginfo not supported");
}
bool
process_stratum_target::supports_non_stop ()
{
return false;
}
bool
process_stratum_target::async (bool enable)
{
return false;
}
int
process_stratum_target::start_non_stop (bool enable)
{
if (enable)
return -1;
else
return 0;
}
bool
process_stratum_target::supports_multi_process ()
{
return false;
}
bool
process_stratum_target::supports_fork_events ()
{
return false;
}
bool
process_stratum_target::supports_vfork_events ()
{
return false;
}
bool
process_stratum_target::supports_exec_events ()
{
return false;
}
void
process_stratum_target::handle_new_gdb_connection ()
{
/* Nop. */
}
int
process_stratum_target::handle_monitor_command (char *mon)
{
return 0;
}
int
process_stratum_target::core_of_thread (ptid_t ptid)
{
return -1;
}
bool
process_stratum_target::supports_read_loadmap ()
{
return false;
}
int
process_stratum_target::read_loadmap (const char *annex,
CORE_ADDR offset,
unsigned char *myaddr,
unsigned int len)
{
gdb_assert_not_reached ("target op read_loadmap not supported");
}
void
process_stratum_target::process_qsupported
(gdb::array_view<const char * const> features)
{
/* Nop. */
}
bool
process_stratum_target::supports_tracepoints ()
{
return false;
}
CORE_ADDR
process_stratum_target::read_pc (regcache *regcache)
{
gdb_assert_not_reached ("process_target::read_pc: Unable to find PC");
}
void
process_stratum_target::write_pc (regcache *regcache, CORE_ADDR pc)
{
gdb_assert_not_reached ("process_target::write_pc: Unable to update PC");
}
bool
process_stratum_target::supports_thread_stopped ()
{
return false;
}
bool
process_stratum_target::thread_stopped (thread_info *thread)
{
gdb_assert_not_reached ("target op thread_stopped not supported");
}
bool
process_stratum_target::supports_get_tib_address ()
{
return false;
}
int
process_stratum_target::get_tib_address (ptid_t ptid, CORE_ADDR *address)
{
gdb_assert_not_reached ("target op get_tib_address not supported");
}
void
process_stratum_target::pause_all (bool freeze)
{
/* Nop. */
}
void
process_stratum_target::unpause_all (bool unfreeze)
{
/* Nop. */
}
void
process_stratum_target::stabilize_threads ()
{
/* Nop. */
}
bool
process_stratum_target::supports_fast_tracepoints ()
{
return false;
}
int
process_stratum_target::install_fast_tracepoint_jump_pad
(CORE_ADDR tpoint, CORE_ADDR tpaddr, CORE_ADDR collector,
CORE_ADDR lockaddr, ULONGEST orig_size, CORE_ADDR *jump_entry,
CORE_ADDR *trampoline, ULONGEST *trampoline_size,
unsigned char *jjump_pad_insn, ULONGEST *jjump_pad_insn_size,
CORE_ADDR *adjusted_insn_addr, CORE_ADDR *adjusted_insn_addr_end,
char *err)
{
gdb_assert_not_reached ("target op install_fast_tracepoint_jump_pad "
"not supported");
}
int
process_stratum_target::get_min_fast_tracepoint_insn_len ()
{
return 0;
}
struct emit_ops *
process_stratum_target::emit_ops ()
{
return nullptr;
}
bool
process_stratum_target::supports_disable_randomization ()
{
return false;
}
bool
process_stratum_target::supports_qxfer_libraries_svr4 ()
{
return false;
}
int
process_stratum_target::qxfer_libraries_svr4 (const char *annex,
unsigned char *readbuf,
unsigned const char *writebuf,
CORE_ADDR offset, int len)
{
gdb_assert_not_reached ("target op qxfer_libraries_svr4 not supported");
}
bool
process_stratum_target::supports_agent ()
{
return false;
}
bool
process_stratum_target::supports_btrace ()
{
return false;
}
btrace_target_info *
process_stratum_target::enable_btrace (thread_info *tp,
const btrace_config *conf)
{
error (_("Target does not support branch tracing."));
}
int
process_stratum_target::disable_btrace (btrace_target_info *tinfo)
{
error (_("Target does not support branch tracing."));
}
int
process_stratum_target::read_btrace (btrace_target_info *tinfo,
buffer *buffer,
enum btrace_read_type type)
{
error (_("Target does not support branch tracing."));
}
int
process_stratum_target::read_btrace_conf (const btrace_target_info *tinfo,
buffer *buffer)
{
error (_("Target does not support branch tracing."));
}
bool
process_stratum_target::supports_range_stepping ()
{
return false;
}
bool
process_stratum_target::supports_pid_to_exec_file ()
{
return false;
}
const char *
process_stratum_target::pid_to_exec_file (int pid)
{
gdb_assert_not_reached ("target op pid_to_exec_file not supported");
}
bool
process_stratum_target::supports_multifs ()
{
return false;
}
int
process_stratum_target::multifs_open (int pid, const char *filename,
int flags, mode_t mode)
{
return open (filename, flags, mode);
}
int
process_stratum_target::multifs_unlink (int pid, const char *filename)
{
return unlink (filename);
}
ssize_t
process_stratum_target::multifs_readlink (int pid, const char *filename,
char *buf, size_t bufsiz)
{
return readlink (filename, buf, bufsiz);
}
int
process_stratum_target::breakpoint_kind_from_pc (CORE_ADDR *pcptr)
{
/* The default behavior is to use the size of a breakpoint as the
kind. */
int size = 0;
sw_breakpoint_from_kind (0, &size);
return size;
}
int
process_stratum_target::breakpoint_kind_from_current_state (CORE_ADDR *pcptr)
{
return breakpoint_kind_from_pc (pcptr);
}
const char *
process_stratum_target::thread_name (ptid_t thread)
{
return nullptr;
}
bool
process_stratum_target::thread_handle (ptid_t ptid, gdb_byte **handle,
int *handle_len)
{
return false;
}
thread_info *
process_stratum_target::thread_pending_parent (thread_info *thread)
{
return nullptr;
}
thread_info *
process_stratum_target::thread_pending_child (thread_info *thread)
{
return nullptr;
}
bool
process_stratum_target::supports_software_single_step ()
{
return false;
}
bool
process_stratum_target::supports_catch_syscall ()
{
return false;
}
int
process_stratum_target::get_ipa_tdesc_idx ()
{
return 0;
}