[COMMIT] Make modiff, save_modiff, other buffer variables into EMACS_INT.

APPROVE COMMIT NOTE: This patch has been committed # HG changeset patch # User Aidan Kehoe <kehoea(a)parhasard.net&gt; # Date 1552238644 0 # Sun Mar 10 17:24:04 2019 +0000 # Node ID 5d1f8a39a8d09a49b87b25c7b27b09fa8b3059c0 # Parent 5aaa9025873317ac1c3054debfddb90c77168838 Make modiff, save_modiff, other buffer variables into EMACS_INT. src/ChangeLog addition: 2019-03-10 Aidan Kehoe <kehoea(a)parhasard.net&gt; Make the modiff, save_modiff, face_change, auto_save_modified buffer slots into EMACS_INTs. Supply and use an arithcompare function for all of them that pays attention to the fact that they wrap around. * buffer.c (Fbuffer_modified_tick): Caution regarding ordinal comparisons with the result of this function. Use make_integer, not make_fixnum, there is no guarantee a fixnum will have the bit width to represent the complete value. * buffer.c (Fbuffer_modified_p): * buffer.c (Fset_buffer_modified_p): * buffer.c (Fkill_buffer): Use buf_tick_arithcompare() in these functions. * buffer.h: * buffer.h (struct buffer_text): * buffer.h (struct buffer): Use EMACS_INT as appropriate in these structures. * buffer.h (buf_tick_arithcompare): New. Compare two buffer tick values, heuristically comparing for wraparound. * fileio.c (Fdo_auto_save): Use buf_tick_arithcompare() as appropriate. * filelock.c (unlock_all_files): * filelock.c (Flock_buffer): * filelock.c (Funlock_buffer): * filelock.c (unlock_buffer): Use buf_tick_arithcompare() as appropriate in these functions. * insdel.c (signal_before_change): * insdel.c (prepare_to_modify_buffer): Use buf_tick_arithcompare() as appropriate in this file. * redisplay.c (regenerate_window_extents_only_changed): * redisplay.c (redisplay_window): * redisplay.c (decode_mode_spec): * redisplay.c (validate_line_start_cache): Use buf_tick_arithcompare() as appropriate in this file. * undo.c (undo_prelude): Ditto. * window.c (Fmove_to_window_line): Ditto. diff -r 5aaa90258733 -r 5d1f8a39a8d0 src/ChangeLog --- a/src/ChangeLog Sun Mar 10 14:06:13 2019 +0000 +++ b/src/ChangeLog Sun Mar 10 17:24:04 2019 +0000 ＠＠ -1,3 +1,45 ＠＠ +2019-03-10 Aidan Kehoe <kehoea(a)parhasard.net&gt; + + Make the modiff, save_modiff, face_change, auto_save_modified + buffer slots into EMACS_INTs. + Supply and use an arithcompare function for all of them that pays + attention to the fact that they wrap around. + * buffer.c (Fbuffer_modified_tick): + Caution regarding ordinal comparisons with the result of this + function. + Use make_integer, not make_fixnum, there is no guarantee a fixnum + will have the bit width to represent the complete value. + * buffer.c (Fbuffer_modified_p): + * buffer.c (Fset_buffer_modified_p): + * buffer.c (Fkill_buffer): + Use buf_tick_arithcompare() in these functions. + * buffer.h: + * buffer.h (struct buffer_text): + * buffer.h (struct buffer): + Use EMACS_INT as appropriate in these structures. + * buffer.h (buf_tick_arithcompare): New. + Compare two buffer tick values, heuristically comparing for + wraparound. + * fileio.c (Fdo_auto_save): + Use buf_tick_arithcompare() as appropriate. + * filelock.c (unlock_all_files): + * filelock.c (Flock_buffer): + * filelock.c (Funlock_buffer): + * filelock.c (unlock_buffer): + Use buf_tick_arithcompare() as appropriate in these functions. + * insdel.c (signal_before_change): + * insdel.c (prepare_to_modify_buffer): + Use buf_tick_arithcompare() as appropriate in this file. + * redisplay.c (regenerate_window_extents_only_changed): + * redisplay.c (redisplay_window): + * redisplay.c (decode_mode_spec): + * redisplay.c (validate_line_start_cache): + Use buf_tick_arithcompare() as appropriate in this file. + * undo.c (undo_prelude): + Ditto. + * window.c (Fmove_to_window_line): + Ditto. + 2019-03-10 Aidan Kehoe <kehoea(a)parhasard.net&gt; * buffer.c (complex_vars_of_buffer): diff -r 5aaa90258733 -r 5d1f8a39a8d0 src/buffer.c --- a/src/buffer.c Sun Mar 10 14:06:13 2019 +0000 +++ b/src/buffer.c Sun Mar 10 17:24:04 2019 +0000 ＠＠ -973,7 +973,8 ＠＠ { struct buffer *buf = decode_buffer (buffer, 0); - return BUF_SAVE_MODIFF (buf) < BUF_MODIFF (buf) ? Qt : Qnil; + return buf_tick_arithcompare (BUF_SAVE_MODIFF (buf), BUF_MODIFF (buf)) < 0 + ? Qt : Qnil; } DEFUN ("set-buffer-modified-p", Fset_buffer_modified_p, 1, 2, 0, /* ＠＠ -993,7 +994,8 ＠＠ Lisp_Object fn = buf->file_truename; if (!NILP (fn)) { - int already = BUF_SAVE_MODIFF (buf) < BUF_MODIFF (buf); + Boolint already = buf_tick_arithcompare (BUF_SAVE_MODIFF (buf), + BUF_MODIFF (buf)) < 0; if (already == NILP (flag)) { int count = specpdl_depth (); ＠＠ -1027,14 +1029,15 ＠＠ DEFUN ("buffer-modified-tick", Fbuffer_modified_tick, 0, 1, 0, /* Return BUFFER's tick counter, incremented for each change in text. Each buffer has a tick counter which is incremented each time the text in -that buffer is changed. It wraps around occasionally. +that buffer is changed. It wraps around occasionally, and so user +code needs to be careful about ordinal comparisons. No argument or nil as argument means use current buffer as BUFFER. */ (buffer)) { struct buffer *buf = decode_buffer (buffer, 0); - return make_fixnum (BUF_MODIFF (buf)); + return make_integer (BUF_MODIFF (buf)); }  DEFUN ("rename-buffer", Frename_buffer, 1, 2, ＠＠ -1245,7 +1248,7 ＠＠ /* Query if the buffer is still modified. */ if (INTERACTIVE && !NILP (b->filename) - && BUF_MODIFF (b) > BUF_SAVE_MODIFF (b)) + && buf_tick_arithcompare (BUF_MODIFF (b), BUF_SAVE_MODIFF (b)) > 0) { Lisp_Object killp; GCPRO1 (buf); diff -r 5aaa90258733 -r 5d1f8a39a8d0 src/buffer.h --- a/src/buffer.h Sun Mar 10 14:06:13 2019 +0000 +++ b/src/buffer.h Sun Mar 10 17:24:04 2019 +0000 ＠＠ -86,12 +86,12 ＠＠ Charbpos bufz; /* Equivalent as a Charbpos. */ Bytecount gap_size;/* Size of buffer's gap */ Bytecount end_gap_size;/* Size of buffer's end gap */ - long modiff; /* This counts buffer-modification events + EMACS_INT modiff; /* This counts buffer-modification events for this buffer. It is incremented for each such event, and never otherwise changed. */ - long save_modiff; /* Previous value of modiff, as of last - time buffer visited or saved a file. */ + EMACS_INT save_modiff; /* Previous value of modiff, as of last + time buffer visited or saved a file. */ #ifdef MULE ＠＠ -172,8 +172,8 ＠＠ Bytebpos zv; /* Index of end of accessible range. */ Charbpos bufzv; /* Equivalent as a Charbpos. */ - int face_change; /* This is set when a change in how the text should - be displayed (e.g., font, color) is made. */ + EMACS_INT face_change; /* This is set when a change in how the text should + be displayed (e.g., font, color) is made. */ /* Whether buffer specific face is specified. */ int buffer_local_face_property; ＠＠ -248,7 +248,7 ＠＠ time_t modtime; /* the value of text->modiff at the last auto-save. */ - long auto_save_modified; + EMACS_INT auto_save_modified; /* The time at which we detected a failure to auto-save, Or -1 if we didn't have a failure. */ ＠＠ -1133,6 +1133,21 ＠＠ /* Modification count */ #define BUF_MODIFF(buf) ((buf)->text->modiff) +/* The modification count wraps around, use the following to compare, which + uses the same approach as Fevent_timestamp_lessp(). */ +DECLARE_INLINE_HEADER ( +int +buf_tick_arithcompare (EMACS_INT val1, EMACS_INT val2) +) +{ + if (val1 < val2 && ((val2 - val1) < (EMACS_INT) ((~(EMACS_UINT)(0) >> 2)))) + { + return -1; + } + + return val1 != val2; +} + /* Saved modification count */ #define BUF_SAVE_MODIFF(buf) ((buf)->text->save_modiff) diff -r 5aaa90258733 -r 5d1f8a39a8d0 src/fileio.c --- a/src/fileio.c Sun Mar 10 14:06:13 2019 +0000 +++ b/src/fileio.c Sun Mar 10 17:24:04 2019 +0000 ＠＠ -4178,9 +4178,12 ＠＠ and file changed since last auto save and file changed since last real save. */ if (STRINGP (b->auto_save_file_name) - && BUF_SAVE_MODIFF (b) < BUF_MODIFF (b) - && b->auto_save_modified < BUF_MODIFF (b) - /* -1 means we've turned off autosaving for a while--see below. */ + && buf_tick_arithcompare (BUF_SAVE_MODIFF (b), + BUF_MODIFF (b)) < 0 + && buf_tick_arithcompare (b->auto_save_modified, + BUF_MODIFF (b)) < 0 + /* -1 means we've turned off autosaving for a while--see + below. */ && XFIXNUM (b->saved_size) >= 0 && (do_handled_files || NILP (Ffind_file_name_handler (b->auto_save_file_name, diff -r 5aaa90258733 -r 5d1f8a39a8d0 src/filelock.c --- a/src/filelock.c Sun Mar 10 14:06:13 2019 +0000 +++ b/src/filelock.c Sun Mar 10 17:24:04 2019 +0000 ＠＠ -405,7 +405,8 ＠＠ for (tail = Vbuffer_alist; CONSP (tail); tail = XCDR (tail)) { struct buffer *b = XBUFFER (XCDR (XCAR (tail))); - if (STRINGP (b->file_truename) && BUF_SAVE_MODIFF (b) < BUF_MODIFF (b)) + if (STRINGP (b->file_truename) + && buf_tick_arithcompare (BUF_SAVE_MODIFF (b), BUF_MODIFF (b)) < 0) unlock_file (b->file_truename); } } ＠＠ -420,7 +421,8 ＠＠ if (NILP (file)) file = current_buffer->file_truename; CHECK_STRING (file); - if (BUF_SAVE_MODIFF (current_buffer) < BUF_MODIFF (current_buffer) + if (buf_tick_arithcompare (BUF_SAVE_MODIFF (current_buffer), + BUF_MODIFF (current_buffer)) < 0 && !NILP (file)) lock_file (file); return Qnil; ＠＠ -437,7 +439,8 ＠＠ mean nasty things with pointy teeth. If you call this make sure you protect things right. */ - if (BUF_SAVE_MODIFF (current_buffer) < BUF_MODIFF (current_buffer) + if (buf_tick_arithcompare (BUF_SAVE_MODIFF (current_buffer), + BUF_MODIFF (current_buffer)) < 0 && STRINGP (current_buffer->file_truename)) unlock_file (current_buffer->file_truename); return Qnil; ＠＠ -453,7 +456,8 ＠＠ /* dmoore - and can destroy current_buffer and all sorts of other mean nasty things with pointy teeth. If you call this make sure you protect things right. */ - if (BUF_SAVE_MODIFF (buffer) < BUF_MODIFF (buffer) + if (buf_tick_arithcompare (BUF_SAVE_MODIFF (buffer), + BUF_MODIFF (buffer)) < 0 && STRINGP (buffer->file_truename)) unlock_file (buffer->file_truename); } diff -r 5aaa90258733 -r 5d1f8a39a8d0 src/insdel.c --- a/src/insdel.c Sun Mar 10 14:06:13 2019 +0000 +++ b/src/insdel.c Sun Mar 10 17:24:04 2019 +0000 ＠＠ -797,7 +797,8 ＠＠ } /* If buffer is unmodified, run a special hook for that case. */ - if (BUF_SAVE_MODIFF (buf) >= BUF_MODIFF (buf)) + if (buf_tick_arithcompare (BUF_SAVE_MODIFF (buf), BUF_MODIFF (buf)) + > -1) { MAP_INDIRECT_BUFFERS (buf, mbuf, bufcons) { ＠＠ -979,7 +980,7 ＠＠ buffer = wrap_buffer (buf); GCPRO1 (buffer); if (!NILP (buf->filename) && lockit && - BUF_SAVE_MODIFF (buf) >= BUF_MODIFF (buf)) + buf_tick_arithcompare (BUF_SAVE_MODIFF (buf), BUF_MODIFF (buf)) >= 0) { #ifdef CLASH_DETECTION if (!NILP (buf->file_truename)) diff -r 5aaa90258733 -r 5d1f8a39a8d0 src/redisplay.c --- a/src/redisplay.c Sun Mar 10 14:06:13 2019 +0000 +++ b/src/redisplay.c Sun Mar 10 17:24:04 2019 +0000 ＠＠ -5805,7 +5805,8 ＠＠ under which this can happen, but I believe that it is probably a reasonable happening. */ if (!point_visible (w, pointm, CURRENT_DISP) - || XFIXNUM (w->last_modified[CURRENT_DISP]) < BUF_MODIFF (b)) + || buf_tick_arithcompare (XFIXNUM (w->last_modified[CURRENT_DISP]), + BUF_MODIFF (b)) < 0) return 0; byte_pointm = charbpos_to_bytebpos (b, pointm); ＠＠ -6490,8 +6491,10 ＠＠ /* If nothing has changed since the last redisplay, then we just need to make sure that point is still visible. */ - if (XFIXNUM (w->last_modified[CURRENT_DISP]) >= BUF_MODIFF (b) - && XFIXNUM (w->last_facechange[CURRENT_DISP]) >= BUF_FACECHANGE (b) + if (buf_tick_arithcompare (XFIXNUM (w->last_modified[CURRENT_DISP]), + BUF_MODIFF (b)) >= 0 + && buf_tick_arithcompare (w->last_facechange[CURRENT_DISP], + BUF_FACECHANGE (b)) >= 0 && pointm >= startp /* This check is to make sure we restore the minibuffer after a temporary change to the echo area. */ ＠＠ -6604,8 +6607,10 ＠＠ && regenerate_window_incrementally (w, startp, pointm)) { if (f->modeline_changed - || XFIXNUM (w->last_modified[CURRENT_DISP]) < BUF_MODIFF (b) - || XFIXNUM (w->last_facechange[CURRENT_DISP]) < BUF_FACECHANGE (b)) + || buf_tick_arithcompare (XFIXNUM (w->last_modified[CURRENT_DISP]), + BUF_MODIFF (b)) < 0 + || buf_tick_arithcompare (XFIXNUM (w->last_facechange[CURRENT_DISP]), + BUF_FACECHANGE (b)) < 0) regenerate_modeline (w); skip_output = 1; ＠＠ -7457,14 +7462,15 ＠＠ /* print %, * or hyphen, if buffer is read-only, modified or neither */ case '*': str = (!NILP (b->read_only) - ? "%" : ((BUF_MODIFF (b) > BUF_SAVE_MODIFF (b)) + ? "%" : (buf_tick_arithcompare (BUF_MODIFF (b), + BUF_SAVE_MODIFF (b)) > 0 ? "*" : "-")); break; /* print * or hyphen -- XEmacs change to allow a buffer to be read-only but still indicate whether it is modified. */ case '+': - str = ((BUF_MODIFF (b) > BUF_SAVE_MODIFF (b)) + str = ((buf_tick_arithcompare (BUF_MODIFF (b), BUF_SAVE_MODIFF (b)) > 0) ? "*" : (!NILP (b->read_only) ? "%" ＠＠ -7475,9 +7481,9 ＠＠ modeline-format doc string. */ /* This differs from %* in that it ignores read-only-ness. */ case '&': - str = ((BUF_MODIFF (b) > BUF_SAVE_MODIFF (b)) + str = (buf_tick_arithcompare (BUF_MODIFF (b), BUF_SAVE_MODIFF (b)) > 0) ? "*" - : "-"); + : "-"; break; /* print process status */ ＠＠ -7840,7 +7846,8 ＠＠ does redisplay will catch it pretty quickly we no longer invalidate the cache if it is set. This greatly speeds up dragging out regions with the mouse. */ - if (XFIXNUM (w->line_cache_last_updated) < BUF_MODIFF (b) + if (buf_tick_arithcompare (XFIXNUM (w->line_cache_last_updated), + BUF_MODIFF (b)) < 0 || f->faces_changed || f->clip_changed) { diff -r 5aaa90258733 -r 5d1f8a39a8d0 src/undo.c --- a/src/undo.c Sun Mar 10 14:06:13 2019 +0000 +++ b/src/undo.c Sun Mar 10 17:24:04 2019 +0000 ＠＠ -85,7 +85,7 ＠＠ if (hack_pending_boundary && NILP (pending_boundary)) pending_boundary = Fcons (Qnil, Qnil); - if (BUF_MODIFF (b) <= BUF_SAVE_MODIFF (b)) + if (buf_tick_arithcompare (BUF_MODIFF (b), BUF_SAVE_MODIFF (b)) <= 0) { /* Record that an unmodified buffer is about to be changed. Record the file modification date so that when undoing this diff -r 5aaa90258733 -r 5d1f8a39a8d0 src/window.c --- a/src/window.c Sun Mar 10 14:06:13 2019 +0000 +++ b/src/window.c Sun Mar 10 17:24:04 2019 +0000 ＠＠ -5126,8 +5126,10 ＠＠ { int retval; - if (XFIXNUM (w->last_modified[CURRENT_DISP]) >= BUF_MODIFF (b) - && XFIXNUM (w->last_facechange[CURRENT_DISP]) >= BUF_FACECHANGE (b)) + if (buf_tick_arithcompare (XFIXNUM (w->last_modified[CURRENT_DISP]), + BUF_MODIFF (b)) >= 0 + && buf_tick_arithcompare (XFIXNUM (w->last_facechange[CURRENT_DISP]), + BUF_FACECHANGE (b)) >= 0) { new_point = point_at_center (w, CURRENT_DISP, 0, 0); -- ‘As I sat looking up at the Guinness ad, I could never figure out / How your man stayed up on the surfboard after forty pints of stout’ (C. Moore)