binutils-gdb/gdb/top.h
Pedro Alves 3eb7562a98 Fix PR gdb/20418 - Problems with synchronous commands and new-ui
When executing commands on a secondary UI running the MI interpreter,
some commands that should be synchronous are not.  MI incorrectly
continues processing input right after the synchronous command is
sent, before the target stops.

The problem happens when we emit MI async events (=library-loaded,
etc.), and we go about restoring the previous terminal state, we end
up calling target_terminal_ours, which incorrectly always installs the
current UI's input_fd in the event loop...  That is, code like this:

   old_chain = make_cleanup_restore_target_terminal ();
   target_terminal_ours_for_output ();

   fprintf_unfiltered (mi->event_channel, "library-loaded");

...

   do_cleanups (old_chain);

The fix is to move the add_file_handler/delete_file_handler calls out
of target_terminal_$foo, making these completely no-ops unless called
with the main UI as current UI.

gdb/ChangeLog:
2016-08-09  Pedro Alves  <palves@redhat.com>

	PR gdb/20418
	* event-top.c (ui_register_input_event_handler)
	(ui_unregister_input_event_handler): New functions.
	(async_enable_stdin): Register input in the event loop.
	(async_disable_stdin): Unregister input from the event loop.
	(gdb_setup_readline): Register input in the event loop.
	* infrun.c (check_curr_ui_sync_execution_done): Register input in
	the event loop.
	* target.c (target_terminal_inferior): Don't unregister input from
	the event loop.
	(target_terminal_ours): Don't register input in the event loop.
	* target.h (target_terminal_inferior)
	(target_terminal_ours_for_output, target_terminal_ours): Update
	comments.
	* top.h (ui_register_input_event_handler)
	(ui_unregister_input_event_handler): New declarations.
	* utils.c (ui_unregister_input_event_handler_cleanup)
	(prepare_to_handle_input): New functions.
	(defaulted_query, prompt_for_continue): Use
	prepare_to_handle_input.

gdb/testsuite/ChangeLog:
2016-08-09  Pedro Alves  <palves@redhat.com>
	    Simon Marchi  <simon.marchi@ericsson.com>

	PR gdb/20418
	* gdb.mi/new-ui-mi-sync.c, gdb.mi/new-ui-mi-sync.exp: New files.
	* lib/mi-support.exp (mi_expect_interrupt): Remove anchors.
2016-08-09 22:50:45 +01:00

282 lines
9.4 KiB
C

/* Top level stuff for GDB, the GNU debugger.
Copyright (C) 1986-2016 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 TOP_H
#define TOP_H
#include "buffer.h"
#include "event-loop.h"
struct tl_interp_info;
/* Prompt state. */
enum prompt_state
{
/* The command line is blocked simulating synchronous execution.
This is used to implement the foreground execution commands
('run', 'continue', etc.). We won't display the prompt and
accept further commands until the execution is actually over. */
PROMPT_BLOCKED,
/* The command finished; display the prompt before returning back to
the top level. */
PROMPT_NEEDED,
/* We've displayed the prompt already, ready for input. */
PROMPTED,
};
/* All about a user interface instance. Each user interface has its
own I/O files/streams, readline state, its own top level
interpreter (for the main UI, this is the interpreter specified
with -i on the command line) and secondary interpreters (for
interpreter-exec ...), etc. There's always one UI associated with
stdin/stdout/stderr, but the user can create secondary UIs, for
example, to create a separate MI channel on its own stdio
streams. */
struct ui
{
/* Pointer to next in singly-linked list. */
struct ui *next;
/* Convenient handle (UI number). Unique across all UIs. */
int num;
/* The UI's command line buffer. This is to used to accumulate
input until we have a whole command line. */
struct buffer line_buffer;
/* The callback used by the event loop whenever an event is detected
on the UI's input file descriptor. This function incrementally
builds a buffer where it accumulates the line read up to the
point of invocation. In the special case in which the character
read is newline, the function invokes the INPUT_HANDLER callback
(see below). */
void (*call_readline) (gdb_client_data);
/* The function to invoke when a complete line of input is ready for
processing. */
void (*input_handler) (char *);
/* True if this UI is using the readline library for command
editing; false if using GDB's own simple readline emulation, with
no editing support. */
int command_editing;
/* Each UI has its own independent set of interpreters. */
struct ui_interp_info *interp_info;
/* True if the UI is in async mode, false if in sync mode. If in
sync mode, a synchronous execution command (e.g, "next") does not
return until the command is finished. If in async mode, then
running a synchronous command returns right after resuming the
target. Waiting for the command's completion is later done on
the top event loop. For the main UI, this starts out disabled,
until all the explicit command line arguments (e.g., `gdb -ex
"start" -ex "next"') are processed. */
int async;
/* The number of nested readline secondary prompts that are
currently active. */
int secondary_prompt_depth;
/* The UI's stdin. Set to stdin for the main UI. */
FILE *stdin_stream;
/* stdio stream that command input is being read from. Set to stdin
normally. Set by source_command to the file we are sourcing.
Set to NULL if we are executing a user-defined command or
interacting via a GUI. */
FILE *instream;
/* Standard output stream. */
FILE *outstream;
/* Standard error stream. */
FILE *errstream;
/* The file descriptor for the input stream, so that we can register
it with the event loop. */
int input_fd;
/* Whether ISATTY returns true on input_fd. Cached here because
quit_force needs to know this _after_ input_fd might be
closed. */
int input_interactive_p;
/* See enum prompt_state's description. */
enum prompt_state prompt_state;
/* The fields below that start with "m_" are "private". They're
meant to be accessed through wrapper macros that make them look
like globals. */
/* The ui_file streams. */
/* Normal results */
struct ui_file *m_gdb_stdout;
/* Input stream */
struct ui_file *m_gdb_stdin;
/* Serious error notifications */
struct ui_file *m_gdb_stderr;
/* Log/debug/trace messages that should bypass normal stdout/stderr
filtering. For moment, always call this stream using
*_unfiltered. In the very near future that restriction shall be
removed - either call shall be unfiltered. (cagney 1999-06-13). */
struct ui_file *m_gdb_stdlog;
/* The current ui_out. */
struct ui_out *m_current_uiout;
};
/* The main UI. This is the UI that is bound to stdin/stdout/stderr.
It always exists and is created automatically when GDB starts
up. */
extern struct ui *main_ui;
/* The current UI. */
extern struct ui *current_ui;
/* The list of all UIs. */
extern struct ui *ui_list;
/* State for SWITCH_THRU_ALL_UIS. Declared here because it is meant
to be created on the stack, but should be treated as opaque. */
struct switch_thru_all_uis
{
struct ui *iter;
struct cleanup *old_chain;
};
/* Functions to drive SWITCH_THRU_ALL_UIS. Though declared here by
necessity, these functions should not be used other than via the
SWITCH_THRU_ALL_UIS macro defined below. */
extern void switch_thru_all_uis_init (struct switch_thru_all_uis *state);
extern int switch_thru_all_uis_cond (struct switch_thru_all_uis *state);
extern void switch_thru_all_uis_next (struct switch_thru_all_uis *state);
/* Traverse through all UI, and switch the current UI to the one
being iterated. */
#define SWITCH_THRU_ALL_UIS(STATE) \
for (switch_thru_all_uis_init (&STATE); \
switch_thru_all_uis_cond (&STATE); \
switch_thru_all_uis_next (&STATE))
/* Traverse over all UIs. */
#define ALL_UIS(UI) \
for (UI = ui_list; UI; UI = UI->next) \
/* Create a new UI. */
extern struct ui *new_ui (FILE *instream, FILE *outstream, FILE *errstream);
extern void delete_ui (struct ui *todel);
/* Cleanup that deletes a UI. */
extern struct cleanup *make_delete_ui_cleanup (struct ui *ui);
/* Cleanup that restores the current UI. */
extern void restore_ui_cleanup (void *data);
/* Register the UI's input file descriptor in the event loop. */
extern void ui_register_input_event_handler (struct ui *ui);
/* Unregister the UI's input file descriptor from the event loop. */
extern void ui_unregister_input_event_handler (struct ui *ui);
/* From top.c. */
extern char *saved_command_line;
extern int in_user_command;
extern int confirm;
extern char gdb_dirbuf[1024];
extern int inhibit_gdbinit;
extern const char gdbinit[];
extern void print_gdb_version (struct ui_file *);
extern void print_gdb_configuration (struct ui_file *);
extern void read_command_file (FILE *);
extern void init_history (void);
extern void command_loop (void);
extern int quit_confirm (void);
extern void quit_force (char *, int);
extern void quit_command (char *, int);
extern void quit_cover (void);
extern void execute_command (char *, int);
/* If the interpreter is in sync mode (we're running a user command's
list, running command hooks or similars), and we just ran a
synchronous command that started the target, wait for that command
to end. WAS_SYNC indicates whether sync_execution was set before
the command was run. */
extern void maybe_wait_sync_command_done (int was_sync);
/* Wait for a synchronous execution command to end. */
extern void wait_sync_command_done (void);
extern void check_frame_language_change (void);
/* Prepare for execution of a command.
Call this before every command, CLI or MI.
Returns a cleanup to be run after the command is completed. */
extern struct cleanup *prepare_execute_command (void);
/* This function returns a pointer to the string that is used
by gdb for its command prompt. */
extern char *get_prompt (void);
/* This function returns a pointer to the string that is used
by gdb for its command prompt. */
extern void set_prompt (const char *s);
/* Return 1 if UI's current input handler is a secondary prompt, 0
otherwise. */
extern int gdb_in_secondary_prompt_p (struct ui *ui);
/* From random places. */
extern int readnow_symbol_files;
/* Perform _initialize initialization. */
extern void gdb_init (char *);
/* For use by event-top.c. */
/* Variables from top.c. */
extern int source_line_number;
extern const char *source_file_name;
extern int history_expansion_p;
extern int server_command;
extern char *lim_at_start;
extern void gdb_add_history (const char *);
extern void show_commands (char *args, int from_tty);
extern void set_history (char *, int);
extern void show_history (char *, int);
extern void set_verbose (char *, int, struct cmd_list_element *);
extern void do_restore_instream_cleanup (void *stream);
extern char *handle_line_of_input (struct buffer *cmd_line_buffer,
char *rl, int repeat,
char *annotation_suffix);
#endif