Move gdbserver to top level

This patch moves gdbserver to the top level.

This patch is as close to a pure move as possible -- gdbserver still
builds its own variant of gnulib and gdbsupport.  Changing this will
be done in a separate patch.

[v2] Note that, per Simon's review comment, this patch changes the
tree so that gdbserver is not built for or1k or score.  This makes
sense, because there is apparently not actually a gdbserver port here.

[v3] This version of the patch also splits out some configury into a
new file, gdbserver/configure.host, so that the top-level configure
script can simply rely on it in order to decide whether gdbserver
should be built.

[v4] This version adds documentation and removes some unnecessary
top-level dependencies.

[v5] Update docs to mention "make all-gdbserver" and change how
top-level configure decides whether to build gdbserver, switching to a
single, shared script.

Tested by the buildbot.

ChangeLog
2020-02-07  Tom Tromey  <tom@tromey.com>
	    Pedro Alves  <palves@redhat.com>

	* src-release.sh (GDB_SUPPORT_DIRS): Add gdbserver.
	* gdbserver: New directory, moved from gdb/gdbserver.
	* configure.ac (host_tools): Add gdbserver.
	Only build gdbserver on certain systems.
	* Makefile.in, configure: Rebuild.
	* Makefile.def (host_modules, dependencies): Add gdbserver.
	* MAINTAINERS: Add gdbserver.

gdb/ChangeLog
2020-02-07  Tom Tromey  <tom@tromey.com>

	* README: Update gdbserver documentation.
	* gdbserver: Move to top level.
	* configure.tgt (build_gdbserver): Remove.
	* configure.ac: Remove --enable-gdbserver.
	* configure: Rebuild.
	* Makefile.in (distclean): Don't mention gdbserver.

Change-Id: I826b7565b54604711dc7a11edea0499cd51ff39e

1 files changed, 147 insertions, 0 deletions

diff --git a/gdbserver/inferiors.h b/gdbserver/inferiors.h
new file mode 100644
index 0000000..4e24b2c
--- /dev/null
+++ b/gdbserver/inferiors.h
@@ -0,0 +1,147 @@
+/* Inferior process information for the remote server for GDB.
+   Copyright (C) 1993-2020 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#ifndef GDBSERVER_INFERIORS_H
+#define GDBSERVER_INFERIORS_H
+
+#include "gdbsupport/gdb_vecs.h"
+#include <list>
+
+struct thread_info;
+struct regcache;
+struct target_desc;
+struct sym_cache;
+struct breakpoint;
+struct raw_breakpoint;
+struct fast_tracepoint_jump;
+struct process_info_private;
+
+struct process_info
+{
+  process_info (int pid_, int attached_)
+  : pid (pid_), attached (attached_)
+  {}
+
+  /* This process' pid.  */
+  int pid;
+
+  /* Nonzero if this child process was attached rather than
+     spawned.  */
+  int attached;
+
+  /* True if GDB asked us to detach from this process, but we remained
+     attached anyway.  */
+  int gdb_detached = 0;
+
+  /* The symbol cache.  */
+  struct sym_cache *symbol_cache = NULL;
+
+  /* The list of memory breakpoints.  */
+  struct breakpoint *breakpoints = NULL;
+
+  /* The list of raw memory breakpoints.  */
+  struct raw_breakpoint *raw_breakpoints = NULL;
+
+  /* The list of installed fast tracepoints.  */
+  struct fast_tracepoint_jump *fast_tracepoint_jumps = NULL;
+
+  /* The list of syscalls to report, or just a single element, ANY_SYSCALL,
+     for unfiltered syscall reporting.  */
+  std::vector<int> syscalls_to_catch;
+
+  const struct target_desc *tdesc = NULL;
+
+  /* Private target data.  */
+  struct process_info_private *priv = NULL;
+};
+
+/* Get the pid of PROC.  */
+
+static inline int
+pid_of (const process_info *proc)
+{
+  return proc->pid;
+}
+
+/* Return a pointer to the process that corresponds to the current
+   thread (current_thread).  It is an error to call this if there is
+   no current thread selected.  */
+
+struct process_info *current_process (void);
+struct process_info *get_thread_process (const struct thread_info *);
+
+extern std::list<process_info *> all_processes;
+
+/* Invoke FUNC for each process.  */
+
+template <typename Func>
+static void
+for_each_process (Func func)
+{
+  std::list<process_info *>::iterator next, cur = all_processes.begin ();
+
+  while (cur != all_processes.end ())
+    {
+      next = cur;
+      next++;
+      func (*cur);
+      cur = next;
+    }
+}
+
+/* Find the first process for which FUNC returns true.  Return NULL if no
+   process satisfying FUNC is found.  */
+
+template <typename Func>
+static process_info *
+find_process (Func func)
+{
+  std::list<process_info *>::iterator next, cur = all_processes.begin ();
+
+  while (cur != all_processes.end ())
+    {
+      next = cur;
+      next++;
+
+      if (func (*cur))
+        return *cur;
+
+      cur = next;
+    }
+
+  return NULL;
+}
+
+extern struct thread_info *current_thread;
+
+/* Return the first process in the processes list.  */
+struct process_info *get_first_process (void);
+
+struct process_info *add_process (int pid, int attached);
+void remove_process (struct process_info *process);
+struct process_info *find_process_pid (int pid);
+int have_started_inferiors_p (void);
+int have_attached_inferiors_p (void);
+
+void clear_inferiors (void);
+
+void *thread_target_data (struct thread_info *);
+struct regcache *thread_regcache_data (struct thread_info *);
+void set_thread_regcache_data (struct thread_info *, struct regcache *);
+
+#endif /* GDBSERVER_INFERIORS_H */