Fix: A potential null_pointer_deference bug
[binutils-gdb.git] / gdbserver / inferiors.cc
blobcbf4677908804b189e33aa1f0d8711395869d069
1 /* Inferior process information for the remote server for GDB.
2 Copyright (C) 2002-2023 Free Software Foundation, Inc.
4 Contributed by MontaVista Software.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 #include "server.h"
22 #include "gdbsupport/common-inferior.h"
23 #include "gdbthread.h"
24 #include "dll.h"
26 std::list<process_info *> all_processes;
27 std::list<thread_info *> all_threads;
29 /* The current process. */
30 static process_info *current_process_;
32 /* The current thread. This is either a thread of CURRENT_PROCESS, or
33 NULL. */
34 struct thread_info *current_thread;
36 /* The current working directory used to start the inferior.
38 Empty if not specified. */
39 static std::string current_inferior_cwd;
41 struct thread_info *
42 add_thread (ptid_t thread_id, void *target_data)
44 thread_info *new_thread = new thread_info (thread_id, target_data);
46 all_threads.push_back (new_thread);
48 if (current_thread == NULL)
49 switch_to_thread (new_thread);
51 return new_thread;
54 /* See gdbthread.h. */
56 struct thread_info *
57 get_first_thread (void)
59 if (!all_threads.empty ())
60 return all_threads.front ();
61 else
62 return NULL;
65 struct thread_info *
66 find_thread_ptid (ptid_t ptid)
68 return find_thread ([&] (thread_info *thread) {
69 return thread->id == ptid;
70 });
73 /* Find a thread associated with the given PROCESS, or NULL if no
74 such thread exists. */
76 static struct thread_info *
77 find_thread_process (const struct process_info *const process)
79 return find_any_thread_of_pid (process->pid);
82 /* See gdbthread.h. */
84 struct thread_info *
85 find_any_thread_of_pid (int pid)
87 return find_thread (pid, [] (thread_info *thread) {
88 return true;
89 });
92 static void
93 free_one_thread (thread_info *thread)
95 delete thread;
98 void
99 remove_thread (struct thread_info *thread)
101 if (thread->btrace != NULL)
102 target_disable_btrace (thread->btrace);
104 discard_queued_stop_replies (ptid_of (thread));
105 all_threads.remove (thread);
106 if (current_thread == thread)
107 switch_to_thread (nullptr);
108 free_one_thread (thread);
111 void *
112 thread_target_data (struct thread_info *thread)
114 return thread->target_data;
117 struct regcache *
118 thread_regcache_data (struct thread_info *thread)
120 return thread->regcache_data;
123 void
124 set_thread_regcache_data (struct thread_info *thread, struct regcache *data)
126 thread->regcache_data = data;
129 void
130 clear_inferiors (void)
132 for_each_thread (free_one_thread);
133 all_threads.clear ();
135 clear_dlls ();
137 switch_to_thread (nullptr);
138 current_process_ = nullptr;
141 struct process_info *
142 add_process (int pid, int attached)
144 process_info *process = new process_info (pid, attached);
146 all_processes.push_back (process);
148 return process;
151 /* Remove a process from the common process list and free the memory
152 allocated for it.
153 The caller is responsible for freeing private data first. */
155 void
156 remove_process (struct process_info *process)
158 clear_symbol_cache (&process->symbol_cache);
159 free_all_breakpoints (process);
160 gdb_assert (find_thread_process (process) == NULL);
161 all_processes.remove (process);
162 if (current_process () == process)
163 switch_to_process (nullptr);
164 delete process;
167 process_info *
168 find_process_pid (int pid)
170 return find_process ([&] (process_info *process) {
171 return process->pid == pid;
175 /* Get the first process in the process list, or NULL if the list is empty. */
177 process_info *
178 get_first_process (void)
180 if (!all_processes.empty ())
181 return all_processes.front ();
182 else
183 return NULL;
186 /* Return non-zero if there are any inferiors that we have created
187 (as opposed to attached-to). */
190 have_started_inferiors_p (void)
192 return find_process ([] (process_info *process) {
193 return !process->attached;
194 }) != NULL;
197 /* Return non-zero if there are any inferiors that we have attached to. */
200 have_attached_inferiors_p (void)
202 return find_process ([] (process_info *process) {
203 return process->attached;
204 }) != NULL;
207 struct process_info *
208 get_thread_process (const struct thread_info *thread)
210 return find_process_pid (thread->id.pid ());
213 struct process_info *
214 current_process (void)
216 return current_process_;
219 /* See gdbsupport/common-gdbthread.h. */
221 void
222 switch_to_thread (process_stratum_target *ops, ptid_t ptid)
224 gdb_assert (ptid != minus_one_ptid);
225 switch_to_thread (find_thread_ptid (ptid));
228 /* See gdbthread.h. */
230 void
231 switch_to_thread (thread_info *thread)
233 if (thread != nullptr)
234 current_process_ = get_thread_process (thread);
235 else
236 current_process_ = nullptr;
237 current_thread = thread;
240 /* See inferiors.h. */
242 void
243 switch_to_process (process_info *proc)
245 current_process_ = proc;
246 current_thread = nullptr;
249 /* See gdbsupport/common-inferior.h. */
251 const std::string &
252 get_inferior_cwd ()
254 return current_inferior_cwd;
257 /* See inferiors.h. */
259 void
260 set_inferior_cwd (std::string cwd)
262 current_inferior_cwd = std::move (cwd);
265 scoped_restore_current_thread::scoped_restore_current_thread ()
267 m_process = current_process_;
268 m_thread = current_thread;
271 scoped_restore_current_thread::~scoped_restore_current_thread ()
273 if (m_dont_restore)
274 return;
276 if (m_thread != nullptr)
277 switch_to_thread (m_thread);
278 else
279 switch_to_process (m_process);