[v2,08/25] Make input_fd be per UI
Commit Message
And with that, we can switch the current UI to the UI whose input
descriptor woke up the event loop. IOW, if the user types in UI 2,
the event loop wakes up, switches to UI 2, and processes the input.
Next the user types in UI 3, the event loop wakes up and switches to
UI 3, etc.
---
gdb/event-top.c | 33 ++++++++++++++-------------------
gdb/event-top.h | 1 -
gdb/linux-nat.c | 2 --
gdb/main.c | 1 +
gdb/remote.c | 2 --
gdb/target.c | 10 ++++++++++
gdb/top.h | 4 ++++
7 files changed, 29 insertions(+), 24 deletions(-)
Comments
Pedro Alves <palves@redhat.com> writes:
> @@ -498,6 +504,10 @@ target_terminal_inferior (void)
> void
> target_terminal_ours (void)
> {
> + struct ui *ui = current_ui;
> +
> + add_file_handler (ui->input_fd, stdin_event_handler, ui);
> +
> if (terminal_state == terminal_is_ours)
> return;
We should call add_file_handler after the terminal_state check above.
On 03/22/2016 09:46 AM, Yao Qi wrote:
> Pedro Alves <palves@redhat.com> writes:
>
>> @@ -498,6 +504,10 @@ target_terminal_inferior (void)
>> void
>> target_terminal_ours (void)
>> {
>> + struct ui *ui = current_ui;
>> +
>> + add_file_handler (ui->input_fd, stdin_event_handler, ui);
>> +
>> if (terminal_state == terminal_is_ours)
>> return;
>
> We should call add_file_handler after the terminal_state check above.
>
We actually shouldn't, because terminal_state only refers to the
state of gdb's main tty state, while we still want to add/remove
the _current_ UI's input_fd from the event loop. I've added
comments in v3.
Note that I'm gradually bubbling up these input_fd calls from the
targets backends towards common code. At some point I'd like to
migrate them somewhere even higher, maybe merged with
async_disable_stdin / async_enable_stdin, now that since the ctrl-c
rework series we only call target_terminal_ours when we really need
input. But that'll be yet another set of
cleaning-up-all-over-the-tree that I'd much rather not do
along with this series.
Thanks,
Pedro Alves
@@ -93,10 +93,6 @@ int async_command_editing_p;
asynchronous execution command. */
int exec_done_display_p = 0;
-/* This is the file descriptor for the input stream that GDB uses to
- read commands from. */
-int input_fd;
-
/* Used by the stdin event handler to compensate for missed stdin events.
Setting this to a non-zero value inside an stdin callback makes the callback
run again. */
@@ -411,12 +407,16 @@ get_command_line_buffer (void)
void
stdin_event_handler (int error, gdb_client_data client_data)
{
- struct ui *ui = current_ui;
+ struct ui *ui = (struct ui *) client_data;
+
+ /* Switch to the UI whose input descriptor woke up the event
+ loop. */
+ current_ui = ui;
if (error)
{
printf_unfiltered (_("error detected on stdin\n"));
- delete_file_handler (input_fd);
+ delete_file_handler (ui->input_fd);
/* If stdin died, we may as well kill gdb. */
quit_command ((char *) 0, stdin == ui->instream);
}
@@ -1044,18 +1044,11 @@ gdb_setup_readline (void)
/* Tell readline to use the same input stream that gdb uses. */
rl_instream = ui->instream;
- /* Get a file descriptor for the input stream, so that we can
- register it with the event loop. */
- input_fd = fileno (ui->instream);
-
- /* Now we need to create the event sources for the input file
- descriptor. */
- /* At this point in time, this is the only event source that we
- register with the even loop. Another source is going to be the
- target program (inferior), but that must be registered only when
- it actually exists (I.e. after we say 'run' or after we connect
- to a remote target. */
- add_file_handler (input_fd, stdin_event_handler, 0);
+ /* Now create the event source for this UI's input file descriptor.
+ Another source is going to be the target program (inferior), but
+ that must be registered only when it actually exists (I.e. after
+ we say 'run' or after we connect to a remote target. */
+ add_file_handler (ui->input_fd, stdin_event_handler, ui);
}
/* Disable command input through the standard CLI channels. Used in
@@ -1064,6 +1057,8 @@ gdb_setup_readline (void)
void
gdb_disable_readline (void)
{
+ struct ui *ui = current_ui;
+
/* FIXME - It is too heavyweight to delete and remake these every
time you run an interpreter that needs readline. It is probably
better to have the interpreters cache these, which in turn means
@@ -1078,5 +1073,5 @@ gdb_disable_readline (void)
#endif
gdb_rl_callback_handler_remove ();
- delete_file_handler (input_fd);
+ delete_file_handler (ui->input_fd);
}
@@ -57,7 +57,6 @@ extern void async_enable_stdin (void);
extern int async_command_editing_p;
extern int exec_done_display_p;
extern struct prompts the_prompts;
-extern int input_fd;
extern void (*after_char_processing_hook) (void);
extern int call_stdin_event_handler_again_p;
extern void gdb_readline_no_editing_callback (void *client_data);
@@ -4287,7 +4287,6 @@ linux_nat_terminal_inferior (struct target_ops *self)
if (!async_terminal_is_ours)
return;
- delete_file_handler (input_fd);
async_terminal_is_ours = 0;
set_sigint_trap ();
}
@@ -4313,7 +4312,6 @@ linux_nat_terminal_ours (struct target_ops *self)
return;
clear_sigint_trap ();
- add_file_handler (input_fd, stdin_event_handler, 0);
async_terminal_is_ours = 1;
}
@@ -507,6 +507,7 @@ captured_main (void *data)
clear_quit_flag ();
saved_command_line = (char *) xstrdup ("");
ui->instream = stdin;
+ ui->input_fd = fileno (stdin);
#ifdef __MINGW32__
/* Ensure stderr is unbuffered. A Cygwin pty or pipe is implemented
@@ -5940,7 +5940,6 @@ remote_terminal_inferior (struct target_ops *self)
can go away. */
if (!remote_async_terminal_ours_p)
return;
- delete_file_handler (input_fd);
remote_async_terminal_ours_p = 0;
async_initialize_sigint_signal_handler ();
/* NOTE: At this point we could also register our selves as the
@@ -5959,7 +5958,6 @@ remote_terminal_ours (struct target_ops *self)
if (remote_async_terminal_ours_p)
return;
async_cleanup_sigint_signal_handler (NULL);
- add_file_handler (input_fd, stdin_event_handler, 0);
remote_async_terminal_ours_p = 1;
}
@@ -43,6 +43,8 @@
#include "agent.h"
#include "auxv.h"
#include "target-debug.h"
+#include "top.h"
+#include "event-top.h"
static void target_info (char *, int);
@@ -477,6 +479,8 @@ target_terminal_is_ours (void)
void
target_terminal_inferior (void)
{
+ struct ui *ui = current_ui;
+
/* A background resume (``run&'') should leave GDB in control of the
terminal. Use target_can_async_p, not target_is_async_p, since at
this point the target is not async yet. However, if sync_execution
@@ -484,6 +488,8 @@ target_terminal_inferior (void)
if (target_can_async_p () && !sync_execution)
return;
+ delete_file_handler (ui->input_fd);
+
if (terminal_state == terminal_is_inferior)
return;
@@ -498,6 +504,10 @@ target_terminal_inferior (void)
void
target_terminal_ours (void)
{
+ struct ui *ui = current_ui;
+
+ add_file_handler (ui->input_fd, stdin_event_handler, ui);
+
if (terminal_state == terminal_is_ours)
return;
@@ -73,6 +73,10 @@ struct ui
interacting via a GUI. */
FILE *instream;
+ /* The file descriptor for the input stream, so that we can register
+ it with the event loop. */
+ int input_fd;
+
/* The fields below that start with "m_" are "private". They're
meant to be accessed through wrapper macros that make them look
like globals. */