From 45bbae5c4b34ef6336cc2a3951f1edf191ff3733 Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Fri, 27 Dec 2019 08:47:41 -0700 Subject: [PATCH] Remove flickering from the TUI In some cases, the TUI flickers when redrawing. This can be seen mostly easily when switching layouts. This patch fixes the problem by exploiting the double buffering that curses already does. In some spots, the TUI will now disable flushing the curses buffers to the screen; and then flush them all at once when the rendering is complete. gdb/ChangeLog 2020-01-19 Tom Tromey * tui/tui.c (tui_show_assembly): Use tui_suppress_output. * tui/tui-wingeneral.h (class tui_suppress_output): New. (tui_wrefresh): Declare. * tui/tui-wingeneral.c (suppress_output): New global. (tui_suppress_output, ~tui_suppress_output): New constructor and destructor. (tui_wrefresh): New function. (tui_gen_win_info::refresh_window): Use tui_wrefresh. (tui_gen_win_info::make_window): Call wnoutrefresh when needed. * tui/tui-regs.h (struct tui_data_window) : Declare method. * tui/tui-regs.c (tui_data_window::erase_data_content): Call tui_wrefresh. (tui_data_window::no_refresh): New method. (tui_data_item_window::refresh_window): Call tui_wrefresh. (tui_reg_command): Use tui_suppress_output * tui/tui-layout.c (tui_set_layout): Use tui_suppress_output. * tui/tui-data.h (struct tui_gen_win_info) : New method. * tui/tui-command.c (tui_refresh_cmd_win): Call tui_wrefresh. Change-Id: Icb832ae100b861de3af3307488e636fa928d5c9f --- gdb/ChangeLog | 23 ++++++++++++++++++++ gdb/tui/tui-command.c | 2 +- gdb/tui/tui-data.h | 7 ++++++ gdb/tui/tui-layout.c | 2 ++ gdb/tui/tui-regs.c | 14 ++++++++++-- gdb/tui/tui-regs.h | 2 ++ gdb/tui/tui-wingeneral.c | 46 ++++++++++++++++++++++++++++++++++++++-- gdb/tui/tui-wingeneral.h | 23 ++++++++++++++++++++ gdb/tui/tui.c | 2 ++ 9 files changed, 116 insertions(+), 5 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index d8482aaaa5..a25f721672 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,26 @@ +2020-01-19 Tom Tromey + + * tui/tui.c (tui_show_assembly): Use tui_suppress_output. + * tui/tui-wingeneral.h (class tui_suppress_output): New. + (tui_wrefresh): Declare. + * tui/tui-wingeneral.c (suppress_output): New global. + (tui_suppress_output, ~tui_suppress_output): New constructor and + destructor. + (tui_wrefresh): New function. + (tui_gen_win_info::refresh_window): Use tui_wrefresh. + (tui_gen_win_info::make_window): Call wnoutrefresh when needed. + * tui/tui-regs.h (struct tui_data_window) : Declare + method. + * tui/tui-regs.c (tui_data_window::erase_data_content): Call + tui_wrefresh. + (tui_data_window::no_refresh): New method. + (tui_data_item_window::refresh_window): Call tui_wrefresh. + (tui_reg_command): Use tui_suppress_output + * tui/tui-layout.c (tui_set_layout): Use tui_suppress_output. + * tui/tui-data.h (struct tui_gen_win_info) : New + method. + * tui/tui-command.c (tui_refresh_cmd_win): Call tui_wrefresh. + 2020-01-19 Tom Tromey * tui/tui-winsource.c (tui_update_source_windows_with_line): diff --git a/gdb/tui/tui-command.c b/gdb/tui/tui-command.c index ba2a802287..42fc59aac6 100644 --- a/gdb/tui/tui-command.c +++ b/gdb/tui/tui-command.c @@ -70,7 +70,7 @@ tui_refresh_cmd_win (void) { WINDOW *w = TUI_CMD_WIN->handle.get (); - wrefresh (w); + tui_wrefresh (w); /* FIXME: It's not clear why this is here. It was present in the original tui_puts code and is kept in order to diff --git a/gdb/tui/tui-data.h b/gdb/tui/tui-data.h index ffdd5e3749..6f86122f58 100644 --- a/gdb/tui/tui-data.h +++ b/gdb/tui/tui-data.h @@ -99,6 +99,13 @@ public: return handle != nullptr; } + /* Disable output until the next call to doupdate. */ + virtual void no_refresh () + { + if (handle != nullptr) + wnoutrefresh (handle.get ()); + } + /* Window handle. */ std::unique_ptr handle; /* Type of window. */ diff --git a/gdb/tui/tui-layout.c b/gdb/tui/tui-layout.c index 01961f550c..3d1e349196 100644 --- a/gdb/tui/tui-layout.c +++ b/gdb/tui/tui-layout.c @@ -113,6 +113,8 @@ tui_set_layout (enum tui_layout_type layout_type) if (new_layout != cur_layout) { + tui_suppress_output suppress; + show_layout (new_layout); /* Now determine where focus should be. */ diff --git a/gdb/tui/tui-regs.c b/gdb/tui/tui-regs.c index 80d1a270e6..bedf55cab8 100644 --- a/gdb/tui/tui-regs.c +++ b/gdb/tui/tui-regs.c @@ -381,7 +381,7 @@ tui_data_window::erase_data_content (const char *prompt) x_pos = half_width - strlen (prompt); mvwaddstr (handle.get (), (height / 2), x_pos, (char *) prompt); } - wrefresh (handle.get ()); + tui_wrefresh (handle.get ()); } /* See tui-regs.h. */ @@ -434,6 +434,14 @@ tui_data_window::refresh_window () win.refresh_window (); } +void +tui_data_window::no_refresh () +{ + tui_gen_win_info::no_refresh (); + for (auto &&win : m_regs_content) + win.no_refresh (); +} + /* This function check all displayed registers for changes in values, given a particular frame. If the values have changed, they are updated with the new value and highlighted. */ @@ -502,7 +510,7 @@ tui_data_item_window::refresh_window () windows, which according to the ncurses man pages aren't well supported. */ touchwin (handle.get ()); - wrefresh (handle.get ()); + tui_wrefresh (handle.get ()); } } @@ -574,6 +582,8 @@ tui_reg_command (const char *args, int from_tty) /* Make sure the curses mode is enabled. */ tui_enable (); + tui_suppress_output suppress; + /* Make sure the register window is visible. If not, select an appropriate layout. We need to do this before trying to run the 'next' or 'prev' commands. */ diff --git a/gdb/tui/tui-regs.h b/gdb/tui/tui-regs.h index 97e02b1a47..eee3689aea 100644 --- a/gdb/tui/tui-regs.h +++ b/gdb/tui/tui-regs.h @@ -70,6 +70,8 @@ struct tui_data_window : public tui_win_info void refresh_window () override; + void no_refresh () override; + const char *name () const override { return DATA_NAME; diff --git a/gdb/tui/tui-wingeneral.c b/gdb/tui/tui-wingeneral.c index 4331f63635..e001a4cd97 100644 --- a/gdb/tui/tui-wingeneral.c +++ b/gdb/tui/tui-wingeneral.c @@ -30,13 +30,51 @@ #include "gdb_curses.h" +/* This is true if we're currently suppressing output, via + wnoutrefresh. This is needed in case we create a new window while + in this mode. */ + +static bool suppress_output; + +/* See tui-data.h. */ + +tui_suppress_output::tui_suppress_output () + : m_saved_suppress (suppress_output) +{ + suppress_output = true; + + for (const auto &win : all_tui_windows ()) + win->no_refresh (); +} + +/* See tui-data.h. */ + +tui_suppress_output::~tui_suppress_output () +{ + suppress_output = m_saved_suppress; + if (!suppress_output) + doupdate (); + + for (const auto &win : all_tui_windows ()) + win->refresh_window (); +} + +/* See tui-data.h. */ + +void +tui_wrefresh (WINDOW *win) +{ + if (!suppress_output) + wrefresh (win); +} + /* See tui-data.h. */ void tui_gen_win_info::refresh_window () { if (handle != NULL) - wrefresh (handle.get ()); + tui_wrefresh (handle.get ()); } /* Draw a border arround the window. */ @@ -134,7 +172,11 @@ tui_gen_win_info::make_window () { handle.reset (newwin (height, width, y, x)); if (handle != NULL) - scrollok (handle.get (), TRUE); + { + if (suppress_output) + wnoutrefresh (handle.get ()); + scrollok (handle.get (), TRUE); + } } void diff --git a/gdb/tui/tui-wingeneral.h b/gdb/tui/tui-wingeneral.h index e32dbed299..a28f27c551 100644 --- a/gdb/tui/tui-wingeneral.h +++ b/gdb/tui/tui-wingeneral.h @@ -33,4 +33,27 @@ extern void tui_unhighlight_win (struct tui_win_info *); extern void tui_highlight_win (struct tui_win_info *); extern void tui_refresh_all (); +/* An RAII class that suppresses output on construction (calling + wnoutrefresh on the existing windows), and then flushes the output + (via doupdate) when destroyed. */ + +class tui_suppress_output +{ +public: + + tui_suppress_output (); + ~tui_suppress_output (); + + DISABLE_COPY_AND_ASSIGN (tui_suppress_output); + +private: + + /* Save the state of the suppression global. */ + bool m_saved_suppress; +}; + +/* Call wrefresh on the given window. However, if output is being + suppressed via tui_suppress_output, do not call wrefresh. */ +extern void tui_wrefresh (WINDOW *win); + #endif /* TUI_TUI_WINGENERAL_H */ diff --git a/gdb/tui/tui.c b/gdb/tui/tui.c index be19ef701d..ae3b9f6072 100644 --- a/gdb/tui/tui.c +++ b/gdb/tui/tui.c @@ -30,6 +30,7 @@ #include "tui/tui-regs.h" #include "tui/tui-stack.h" #include "tui/tui-win.h" +#include "tui/tui-wingeneral.h" #include "tui/tui-winsource.h" #include "tui/tui-source.h" #include "target.h" @@ -577,6 +578,7 @@ tui_disable_command (const char *args, int from_tty) void tui_show_assembly (struct gdbarch *gdbarch, CORE_ADDR addr) { + tui_suppress_output suppress; tui_add_win_to_layout (DISASSEM_WIN); tui_update_source_windows_with_addr (gdbarch, addr); } -- 2.34.1