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Diffstat (limited to 'gdbserver/target.c')
| -rw-r--r-- | gdbserver/target.c | 395 |
1 files changed, 395 insertions, 0 deletions
diff --git a/gdbserver/target.c b/gdbserver/target.c new file mode 100644 index 0000000..a4593cf --- /dev/null +++ b/gdbserver/target.c @@ -0,0 +1,395 @@ +/* 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 <http://www.gnu.org/licenses/>. */ + +#include "server.h" +#include "tracepoint.h" +#include "gdbsupport/byte-vector.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; + + if (the_target->prepare_to_access_memory != NULL) + { + int res; + + res = the_target->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 (); + + if (the_target->done_accessing_memory != NULL) + the_target->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->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->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->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->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 != 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), "<all threads>"); + else if (ptid == null_ptid) + xsnprintf (buf, sizeof (buf), "<null thread>"); + 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->kill) (proc); +} + +/* Target can do hardware single step. */ + +int +target_can_do_hardware_single_step (void) +{ + return 1; +} + +/* 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. */ +} |