Introduce interpreter factories

If every UI instance has its own set of interpreters, then the current
scheme of creating the interpreters at GDB initialization time no
longer works.  We need to create them whenever a new UI instance is
created.

The scheme implemented here has each interpreter register a factory
callback that when called creates a new instance of a specific
interpreter type.  Then, when some code in gdb looks up an interpreter
(always by name), if there's none yet, the factory method is called to
construct one.

gdb/ChangeLog:
2016-06-21  Pedro Alves  <palves@redhat.com>

	* cli/cli-interp.c (cli_uiout): Delete, moved into ...
	(struct cli_interp): ... this new structure.
	(cli_on_normal_stop, cli_on_signal_received)
	(cli_on_end_stepping_range, cli_on_signal_exited, cli_on_exited)
	(cli_on_no_history): Use interp_ui_out.
	(cli_interpreter_init): If top level, set the cli_interp global.
	(cli_interpreter_init): Return the interp's data instead of NULL.
	(cli_interpreter_resume, cli_interpreter_exec, cli_ui_out): Adjust
	to cli_uiout being in the interpreter's data.
	(cli_interp_procs): New, factored out from _initialize_cli_interp.
	(cli_interp_factory): New function.
	(_initialize_cli_interp): Call interp_factory_register.
	* interps.c (get_interp_info): New, factored out from ...
	(get_current_interp_info): ... this.
	(interp_new): Add parameter 'data'.  Store it.
	(struct interp_factory): New function.
	(interp_factory_p): New typedef.  Define a VEC_P.
	(interpreter_factories): New global.
	(interp_factory_register): New function.
	(interp_add): Add 'ui' parameter.  Use get_interp_info and
	interp_lookup_existing.
	(interp_lookup): Rename to ...
	(interp_lookup_existing): ... this.  Add 'ui' parameter.  Don't
	check for NULL or empty name here.
	(interp_lookup): Add 'ui' parameter and reimplement.
	(interp_set_temp, interpreter_exec_cmd): Adjust.
	(interpreter_completer): Complete on registered interpreter
	factories instead of interpreters.
	* interps.h (interp_factory_func): New typedef.
	(interp_factory_register): Declare.
	(interp_new, interp_add): Adjust.
	(interp_lookup): Declare.
	* main.c (captured_main): Adjust.
	* mi/mi-interp.c (mi_cmd_interpreter_exec): Adjust.
	(mi_interp_procs): New, factored out from
	_initialize_mi_interp.
	(mi_interp_factory): New function.
	* python/python.c (execute_gdb_command): Adjust.
	* tui/tui-interp.c (tui_init): If top level, set the tui_interp
	global.
	(tui_interp_procs): New.
	(tui_interp_factory): New function.
	(_initialize_tui_interp): Call interp_factory_register.

1 files changed, 55 insertions, 32 deletions

diff --git a/gdb/cli/cli-interp.c b/gdb/cli/cli-interp.c
index dfbd808..8eae0ac 100644
--- a/gdb/cli/cli-interp.c
+++ b/gdb/cli/cli-interp.c
@@ -26,9 +26,14 @@
 #include "infrun.h"
 #include "observer.h"
 
-/* These are the ui_out and the interpreter for the console
-   interpreter.  */
-struct ui_out *cli_uiout;
+/* The console interpreter.  */
+struct cli_interp
+{
+  /* The ui_out for the console interpreter.  */
+  struct ui_out *cli_uiout;
+};
+
+/* The interpreter for the console interpreter.  */
 static struct interp *cli_interp;
 
 /* Longjmp-safe wrapper for "execute_command".  */
@@ -48,7 +53,7 @@ cli_on_normal_stop (struct bpstats *bs, int print_frame)
   if (!interp_quiet_p (cli_interp))
     {
       if (print_frame)
-	print_stop_event (cli_uiout);
+	print_stop_event (interp_ui_out (cli_interp));
     }
 }
 
@@ -58,7 +63,7 @@ static void
 cli_on_signal_received (enum gdb_signal siggnal)
 {
   if (!interp_quiet_p (cli_interp))
-    print_signal_received_reason (cli_uiout, siggnal);
+    print_signal_received_reason (interp_ui_out (cli_interp), siggnal);
 }
 
 /* Observer for the end_stepping_range notification.  */
@@ -67,7 +72,7 @@ static void
 cli_on_end_stepping_range (void)
 {
   if (!interp_quiet_p (cli_interp))
-    print_end_stepping_range_reason (cli_uiout);
+    print_end_stepping_range_reason (interp_ui_out (cli_interp));
 }
 
 /* Observer for the signalled notification.  */
@@ -76,7 +81,7 @@ static void
 cli_on_signal_exited (enum gdb_signal siggnal)
 {
   if (!interp_quiet_p (cli_interp))
-    print_signal_exited_reason (cli_uiout, siggnal);
+    print_signal_exited_reason (interp_ui_out (cli_interp), siggnal);
 }
 
 /* Observer for the exited notification.  */
@@ -85,7 +90,7 @@ static void
 cli_on_exited (int exitstatus)
 {
   if (!interp_quiet_p (cli_interp))
-    print_exited_reason (cli_uiout, exitstatus);
+    print_exited_reason (interp_ui_out (cli_interp), exitstatus);
 }
 
 /* Observer for the no_history notification.  */
@@ -94,7 +99,7 @@ static void
 cli_on_no_history (void)
 {
   if (!interp_quiet_p (cli_interp))
-    print_no_history_reason (cli_uiout);
+    print_no_history_reason (interp_ui_out (cli_interp));
 }
 
 /* Observer for the sync_execution_done notification.  */
@@ -120,6 +125,9 @@ cli_on_command_error (void)
 static void *
 cli_interpreter_init (struct interp *self, int top_level)
 {
+  if (top_level)
+    cli_interp = self;
+
   /* If changing this, remember to update tui-interp.c as well.  */
   observer_attach_normal_stop (cli_on_normal_stop);
   observer_attach_end_stepping_range (cli_on_end_stepping_range);
@@ -130,12 +138,13 @@ cli_interpreter_init (struct interp *self, int top_level)
   observer_attach_sync_execution_done (cli_on_sync_execution_done);
   observer_attach_command_error (cli_on_command_error);
 
-  return NULL;
+  return interp_data (self);
 }
 
 static int
 cli_interpreter_resume (void *data)
 {
+  struct cli_interp *cli = (struct cli_interp *) data;
   struct ui_file *stream;
 
   /*sync_execution = 1; */
@@ -144,17 +153,17 @@ cli_interpreter_resume (void *data)
      previously writing to gdb_stdout, then set it to the new
      gdb_stdout afterwards.  */
 
-  stream = cli_out_set_stream (cli_uiout, gdb_stdout);
+  stream = cli_out_set_stream (cli->cli_uiout, gdb_stdout);
   if (stream != gdb_stdout)
     {
-      cli_out_set_stream (cli_uiout, stream);
+      cli_out_set_stream (cli->cli_uiout, stream);
       stream = NULL;
     }
 
   gdb_setup_readline ();
 
   if (stream != NULL)
-    cli_out_set_stream (cli_uiout, gdb_stdout);
+    cli_out_set_stream (cli->cli_uiout, gdb_stdout);
 
   return 1;
 }
@@ -169,6 +178,7 @@ cli_interpreter_suspend (void *data)
 static struct gdb_exception
 cli_interpreter_exec (void *data, const char *command_str)
 {
+  struct cli_interp *cli = (struct cli_interp *) data;
   struct ui_file *old_stream;
   struct gdb_exception result;
 
@@ -184,9 +194,9 @@ cli_interpreter_exec (void *data, const char *command_str)
 
      It is important that it gets reset everytime, since the user
      could set gdb to use a different interpreter.  */
-  old_stream = cli_out_set_stream (cli_uiout, gdb_stdout);
-  result = safe_execute_command (cli_uiout, str, 1);
-  cli_out_set_stream (cli_uiout, old_stream);
+  old_stream = cli_out_set_stream (cli->cli_uiout, gdb_stdout);
+  result = safe_execute_command (cli->cli_uiout, str, 1);
+  cli_out_set_stream (cli->cli_uiout, old_stream);
   return result;
 }
 
@@ -222,7 +232,34 @@ safe_execute_command (struct ui_out *command_uiout, char *command, int from_tty)
 static struct ui_out *
 cli_ui_out (struct interp *self)
 {
-  return cli_uiout;
+  struct cli_interp *cli = (struct cli_interp *) interp_data (self);
+
+  return cli->cli_uiout;
+}
+
+/* The CLI interpreter's vtable.  */
+
+static const struct interp_procs cli_interp_procs = {
+  cli_interpreter_init,		/* init_proc */
+  cli_interpreter_resume,	/* resume_proc */
+  cli_interpreter_suspend,	/* suspend_proc */
+  cli_interpreter_exec,		/* exec_proc */
+  cli_ui_out,			/* ui_out_proc */
+  NULL,                       	/* set_logging_proc */
+  cli_command_loop            	/* command_loop_proc */
+};
+
+/* Factory for CLI interpreters.  */
+
+static struct interp *
+cli_interp_factory (const char *name)
+{
+  struct cli_interp *cli = XNEW (struct cli_interp);
+
+  /* Create a default uiout builder for the CLI.  */
+  cli->cli_uiout = cli_out_new (gdb_stdout);
+
+  return interp_new (name, &cli_interp_procs, cli);
 }
 
 /* Standard gdb initialization hook.  */
@@ -231,19 +268,5 @@ extern initialize_file_ftype _initialize_cli_interp; /* -Wmissing-prototypes */
 void
 _initialize_cli_interp (void)
 {
-  static const struct interp_procs procs = {
-    cli_interpreter_init,	/* init_proc */
-    cli_interpreter_resume,	/* resume_proc */
-    cli_interpreter_suspend,	/* suspend_proc */
-    cli_interpreter_exec,	/* exec_proc */
-    cli_ui_out,			/* ui_out_proc */
-    NULL,                       /* set_logging_proc */
-    cli_command_loop            /* command_loop_proc */
-  };
-
-  /* Create a default uiout builder for the CLI.  */
-  cli_uiout = cli_out_new (gdb_stdout);
-  cli_interp = interp_new (INTERP_CONSOLE, &procs);
-
-  interp_add (cli_interp);
+  interp_factory_register (INTERP_CONSOLE, cli_interp_factory);
 }