From a350efd4fb368a35ada608f6bc26ccd3bed0ae6b Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Tue, 16 Jun 2020 17:55:57 -0600 Subject: [PATCH] Fix crash when exiting TUI with gdb -tui PR tui/25348 points out that, when "gdb -tui" is used, then exiting the TUI will cause a crash. This happens because tui_setup_io stashes some readline variables -- but because this happens before readline is initialized, some of these are NULL. Then, when exiting the TUI, the NULL values are "restored", causing a crash in readline. This patch fixes the problem by ensuring that readline is initialized first. Back in commit 11061048d ("Give a name to the TUI SingleKey keymap"), a call to rl_initialize was removed from tui_initialize_readline; this patch resurrects the call, but moves it to the end of the function, so as not to remove the ability to modify the SingleKey map from .inputrc. gdb/ChangeLog 2020-06-16 Tom Tromey PR tui/25348: * tui/tui.c (tui_ensure_readline_initialized): Rename from tui_initialize_readline. Only run once. Call rl_initialize. * tui/tui.h (tui_ensure_readline_initialized): Rename from tui_initialize_readline. * tui/tui-io.c (tui_setup_io): Call tui_ensure_readline_initialized. * tui/tui-interp.c (tui_interp::init): Update. --- gdb/ChangeLog | 11 +++++++++++ gdb/tui/tui-interp.c | 2 +- gdb/tui/tui-io.c | 4 ++++ gdb/tui/tui.c | 11 ++++++++++- gdb/tui/tui.h | 6 +++--- 5 files changed, 29 insertions(+), 5 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 316b3fad288..dc269261beb 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,14 @@ +2020-06-16 Tom Tromey + + PR tui/25348: + * tui/tui.c (tui_ensure_readline_initialized): Rename from + tui_initialize_readline. Only run once. Call rl_initialize. + * tui/tui.h (tui_ensure_readline_initialized): Rename from + tui_initialize_readline. + * tui/tui-io.c (tui_setup_io): Call + tui_ensure_readline_initialized. + * tui/tui-interp.c (tui_interp::init): Update. + 2020-06-16 Tom Tromey * tui/tui-layout.c (tui_layout_split::remove_windows): Fix logic. diff --git a/gdb/tui/tui-interp.c b/gdb/tui/tui-interp.c index 10118af2741..44a13964323 100644 --- a/gdb/tui/tui-interp.c +++ b/gdb/tui/tui-interp.c @@ -244,7 +244,7 @@ tui_interp::init (bool top_level) tui_initialize_io (); tui_initialize_win (); if (gdb_stdout->isatty ()) - tui_initialize_readline (); + tui_ensure_readline_initialized (); } void diff --git a/gdb/tui/tui-io.c b/gdb/tui/tui-io.c index e7a8ac77bce..277b560af4f 100644 --- a/gdb/tui/tui-io.c +++ b/gdb/tui/tui-io.c @@ -746,6 +746,10 @@ tui_setup_io (int mode) if (mode) { + /* Ensure that readline has been initialized before saving any + of its variables. */ + tui_ensure_readline_initialized (); + /* Redirect readline to TUI. */ tui_old_rl_redisplay_function = rl_redisplay_function; tui_old_rl_deprep_terminal = rl_deprep_term_function; diff --git a/gdb/tui/tui.c b/gdb/tui/tui.c index ac435d16d6c..828e42bccf7 100644 --- a/gdb/tui/tui.c +++ b/gdb/tui/tui.c @@ -268,8 +268,14 @@ tui_set_key_mode (enum tui_key_mode mode) /* Initialize readline and configure the keymap for the switching key shortcut. */ void -tui_initialize_readline (void) +tui_ensure_readline_initialized () { + static bool initialized; + + if (initialized) + return; + initialized = true; + int i; Keymap tui_ctlx_keymap; @@ -325,6 +331,9 @@ tui_initialize_readline (void) rl_bind_key_in_map ('q', tui_rl_next_keymap, tui_keymap); rl_bind_key_in_map ('s', tui_rl_next_keymap, emacs_ctlx_keymap); rl_bind_key_in_map ('s', tui_rl_next_keymap, tui_ctlx_keymap); + + /* Initialize readline after the above. */ + rl_initialize (); } /* Return the TERM variable from the environment, or "" diff --git a/gdb/tui/tui.h b/gdb/tui/tui.h index 816b1e92851..79525babc9f 100644 --- a/gdb/tui/tui.h +++ b/gdb/tui/tui.h @@ -49,9 +49,9 @@ extern bool tui_is_window_visible (enum tui_win_type type); extern bool tui_get_command_dimension (unsigned int *width, unsigned int *height); -/* Initialize readline and configure the keymap for the switching - key shortcut. */ -extern void tui_initialize_readline (void); +/* Initialize readline and configure the keymap for the switching key + shortcut. May be called more than once without issue. */ +extern void tui_ensure_readline_initialized (); /* Enter in the tui mode (curses). */ extern void tui_enable (void); -- 2.30.2