From 33be50037c2b4cdb002538534e9915c6bad253b7 Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Wed, 1 Feb 2017 15:18:43 -0800 Subject: Remove immediate_quit. The old code that sets and clears immediate_quit was ineffective except when Emacs is running in terminal mode, and has problematic race conditions anyway, so remove it. This will introduce some hangs when Emacs runs in terminal mode, and these hangs should be fixed in followup patches. * src/keyboard.c (immediate_quit): Remove. All uses removed. --- src/eval.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'src/eval.c') diff --git a/src/eval.c b/src/eval.c index 62d4af15e27..844879d6a2d 100644 --- a/src/eval.c +++ b/src/eval.c @@ -1131,7 +1131,6 @@ unwind_to_catch (struct handler *catch, Lisp_Object value) /* Restore certain special C variables. */ set_poll_suppress_count (catch->poll_suppress_count); unblock_input_to (catch->interrupt_input_blocked); - immediate_quit = false; do { @@ -1517,7 +1516,6 @@ signal_or_quit (Lisp_Object error_symbol, Lisp_Object data, bool keyboard_quit) Lisp_Object clause = Qnil; struct handler *h; - immediate_quit = false; if (gc_in_progress || waiting_for_input) emacs_abort (); -- cgit v1.2.1 From b01ac672be1277833964d2d53f6dd26560c70343 Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Wed, 1 Feb 2017 15:18:44 -0800 Subject: Revamp quitting and fix infloops This fixes some infinite loops that cannot be quitted out of, e.g., (defun foo () (nth most-positive-fixnum '#1=(1 . #1#))) when byte-compiled and when run under X. See: http://lists.gnu.org/archive/html/emacs-devel/2017-01/msg00577.html This also attempts to keep the performance improvements I recently added, as much as possible under the constraint that the infloops must be caught. In some cases this fixes infloop bugs recently introduced when I removed immediate_quit. * src/alloc.c (Fmake_list): Use rarely_quit, not maybe_quit, for speed in the usual case. * src/bytecode.c (exec_byte_code): * src/editfns.c (Fcompare_buffer_substrings): * src/fns.c (Fnthcdr): * src/syntax.c (scan_words, skip_chars, skip_syntaxes) (Fbackward_prefix_chars): Use rarely_quit so that users can C-g out of long loops. * src/callproc.c (call_process_cleanup, call_process): * src/fileio.c (read_non_regular, Finsert_file_contents): * src/indent.c (compute_motion): * src/syntax.c (scan_words, Fforward_comment): Remove now-unnecessary maybe_quit calls. * src/callproc.c (call_process): * src/doc.c (get_doc_string, Fsnarf_documentation): * src/fileio.c (Fcopy_file, read_non_regular, Finsert_file_contents): * src/lread.c (safe_to_load_version): * src/sysdep.c (system_process_attributes) [GNU_LINUX]: Use emacs_read_quit instead of emacs_read in places where C-g handling is safe. * src/eval.c (maybe_quit): Move comment here from lisp.h. * src/fileio.c (Fcopy_file, e_write): Use emacs_write_quit instead of emacs_write_sig in places where C-g handling is safe. * src/filelock.c (create_lock_file): Use emacs_write, not plain write, as emacs_write no longer has a problem. (read_lock_data): Use emacs_read, not read, as emacs_read no longer has a problem. * src/fns.c (rarely_quit): Move to lisp.h and rename to incr_rarely_quit. All uses changed.. * src/fns.c (Fmemq, Fmemql, Fassq, Frassq, Fplist_put, Fplist_member): * src/indent.c (compute_motion): * src/syntax.c (find_defun_start, back_comment, forw_comment) (Fforward_comment, scan_lists, scan_sexps_forward): Use incr_rarely_quit so that users can C-g out of long loops. * src/fns.c (Fnconc): Move incr_rarely_quit call to within inner loop, so that it catches C-g there too. * src/keyboard.c (tty_read_avail_input): Remove commented-out and now-obsolete code dealing with interrupts. * src/lisp.h (rarely_quit, incr_rarely_quit): New functions, the latter moved here from fns.c and renamed from rarely_quit. (emacs_read_quit, emacs_write_quit): New decls. * src/search.c (find_newline, search_buffer, find_newline1): Add maybe_quit to catch C-g. * src/sysdep.c (get_child_status): Always invoke maybe_quit if interruptible, so that the caller need not bother. (emacs_nointr_read, emacs_read_quit, emacs_write_quit): New functions. (emacs_read): Rewrite in terms of emacs_nointr_read. Do not handle C-g or signals; that is now for emacs_read_quit. (emacs_full_write): Replace PROCESS_SIGNALS two-way arg with INTERRUPTIBLE three-way arg. All uses changed. --- src/eval.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'src/eval.c') diff --git a/src/eval.c b/src/eval.c index 844879d6a2d..22b02b49521 100644 --- a/src/eval.c +++ b/src/eval.c @@ -1461,6 +1461,19 @@ process_quit_flag (void) quit (); } +/* Check quit-flag and quit if it is non-nil. Typing C-g does not + directly cause a quit; it only sets Vquit_flag. So the program + needs to call maybe_quit at times when it is safe to quit. Every + loop that might run for a long time or might not exit ought to call + maybe_quit at least once, at a safe place. Unless that is + impossible, of course. But it is very desirable to avoid creating + loops where maybe_quit is impossible. + + If quit-flag is set to `kill-emacs' the SIGINT handler has received + a request to exit Emacs when it is safe to do. + + When not quitting, process any pending signals. */ + void maybe_quit (void) { -- cgit v1.2.1