1 files changed, 162 insertions, 0 deletions
diff --git a/gdb/target-connection.c b/gdb/target-connection.c
new file mode 100644
index 0000000..35c786b
--- /dev/null
+++ b/gdb/target-connection.c
@@ -0,0 +1,162 @@
+/* List of target connections for GDB.
+
+   Copyright (C) 2017-2020 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/>.  */
+
+#include "defs.h"
+#include "target-connection.h"
+
+#include <map>
+
+#include "inferior.h"
+#include "target.h"
+
+/* A map between connection number and representative process_stratum
+   target.  */
+static std::map<int, process_stratum_target *> process_targets;
+
+/* The highest connection number ever given to a target.  */
+static int highest_target_connection_num;
+
+/* See target-connection.h.  */
+
+void
+connection_list_add (process_stratum_target *t)
+{
+  if (t->connection_number == 0)
+    {
+      t->connection_number = ++highest_target_connection_num;
+      process_targets[t->connection_number] = t;
+    }
+}
+
+/* See target-connection.h.  */
+
+void
+connection_list_remove (process_stratum_target *t)
+{
+  process_targets.erase (t->connection_number);
+  t->connection_number = 0;
+}
+
+/* Make a target connection string for T.  This is usually T's
+   shortname, but it includes the result of
+   process_stratum_target::connection_string() too if T supports
+   it.  */
+
+static std::string
+make_target_connection_string (process_stratum_target *t)
+{
+  if (t->connection_string () != NULL)
+    return string_printf ("%s %s", t->shortname (),
+			  t->connection_string ());
+  else
+    return t->shortname ();
+}
+
+/* Prints the list of target connections and their details on UIOUT.
+
+   If REQUESTED_CONNECTIONS is not NULL, it's a list of GDB ids of the
+   target connections that should be printed.  Otherwise, all target
+   connections are printed.  */
+
+static void
+print_connection (struct ui_out *uiout, const char *requested_connections)
+{
+  int count = 0;
+  size_t what_len = 0;
+
+  /* Compute number of lines we will print.  */
+  for (const auto &it : process_targets)
+    {
+      if (!number_is_in_list (requested_connections, it.first))
+	continue;
+
+      ++count;
+
+      process_stratum_target *t = it.second;
+
+      size_t l = strlen (t->shortname ());
+      if (t->connection_string () != NULL)
+	l += 1 + strlen (t->connection_string ());
+
+      if (l > what_len)
+	what_len = l;
+    }
+
+  if (count == 0)
+    {
+      uiout->message (_("No connections.\n"));
+      return;
+    }
+
+  ui_out_emit_table table_emitter (uiout, 4, process_targets.size (),
+				   "connections");
+
+  uiout->table_header (1, ui_left, "current", "");
+  uiout->table_header (4, ui_left, "number", "Num");
+  /* The text in the "what" column may include spaces.  Add one extra
+     space to visually separate the What and Description columns a
+     little better.  Compare:
+      "* 1    remote :9999 Remote serial target in gdb-specific protocol"
+      "* 1    remote :9999  Remote serial target in gdb-specific protocol"
+  */
+  uiout->table_header (what_len + 1, ui_left, "what", "What");
+  uiout->table_header (17, ui_left, "description", "Description");
+
+  uiout->table_body ();
+
+  for (const auto &it : process_targets)
+    {
+      process_stratum_target *t = it.second;
+
+      if (!number_is_in_list (requested_connections, t->connection_number))
+	continue;
+
+      ui_out_emit_tuple tuple_emitter (uiout, NULL);
+
+      if (current_inferior ()->process_target () == t)
+	uiout->field_string ("current", "*");
+      else
+	uiout->field_skip ("current");
+
+      uiout->field_signed ("number", t->connection_number);
+
+      uiout->field_string ("what", make_target_connection_string (t).c_str ());
+
+      uiout->field_string ("description", t->longname ());
+
+      uiout->text ("\n");
+    }
+}
+
+/* The "info connections" command.  */
+
+static void
+info_connections_command (const char *args, int from_tty)
+{
+  print_connection (current_uiout, args);
+}
+
+void
+_initialize_target_connection ()
+{
+  add_info ("connections", info_connections_command,
+	    _("\
+Target connections in use.\n\
+Shows the list of target connections currently in use."));
+}