Make instream be per UI

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

	* cli/cli-script.c (execute_user_command, read_next_line)
	(read_next_line): Adjust to per-UI instream.
	* event-top.c (stdin_event_handler, command_handler)
	(handle_line_of_input, command_line_handler)
	(gdb_readline_no_editing_callback, async_sigterm_handler)
	(gdb_setup_readline): Likewise.
	* inflow.c: Include top.h.
	(gdb_has_a_terminal, child_terminal_init_with_pgrp)
	(gdb_save_tty_state, child_terminal_inferior)
	(child_terminal_ours_1, copy_terminal_info): Use the main UI.
	(initialize_stdin_serial): Adjust to per-UI instream.
	* main.c (captured_command_loop, captured_main): Adjust to per-UI
	instream.
	* mi/mi-interp.c (mi_execute_command_wrapper): Likewise.
	* python/python.c (python_interactive_command): Likewise.
	* terminal.h (struct ui): Forward declare.
	(initialize_stdin_serial): Add struct ui parameter.
	* top.c (instream): Delete.
	(do_restore_instream_cleanup, read_command_file, dont_repeat)
	(gdb_readline_no_editing, command_line_input)
	(input_from_terminal_p, gdb_init): Adjust to per-UI instream.
	* top.h (struct ui) <instream>: New field.
	(instream): Delete declaration.
	(quit): Adjust to per-UI instream.

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

	* gdb.gdb/selftest.exp (do_steps_and_nexts): Add new regexp.

1 files changed, 5 insertions, 2 deletions

diff --git a/gdb/main.c b/gdb/main.c
index 221888d..2b763a3 100644
--- a/gdb/main.c
+++ b/gdb/main.c
@@ -309,6 +309,8 @@ setup_alternate_signal_stack (void)
 static int
 captured_command_loop (void *data)
 {
+  struct ui *ui = current_ui;
+
   /* Top-level execution commands can be run in the background from
      here on.  */
   current_ui->async = 1;
@@ -326,7 +328,7 @@ captured_command_loop (void *data)
      error) we try to quit.  If the quit is aborted, catch_errors()
      which called this catch the signal and restart the command
      loop.  */
-  quit_command (NULL, instream == stdin);
+  quit_command (NULL, ui->instream == stdin);
   return 1;
 }
 
@@ -435,6 +437,7 @@ DEF_VEC_O (cmdarg_s);
 static int
 captured_main (void *data)
 {
+  struct ui *ui = current_ui;
   struct captured_main_args *context = (struct captured_main_args *) data;
   int argc = context->argc;
   char **argv = context->argv;
@@ -504,7 +507,7 @@ captured_main (void *data)
   ndir = 0;
 
   saved_command_line = (char *) xstrdup ("");
-  instream = stdin;
+  ui->instream = stdin;
 
 #ifdef __MINGW32__
   /* Ensure stderr is unbuffered.  A Cygwin pty or pipe is implemented