* src/term.c (init_tty): When COLORTERM=truecolor is defined,
override setaf/setab/colors terminfo capabilities with 24-bit
color support.

* doc/misc/efaq.texi (Colors on a TTY): Mention the possibility to
enable 24-bit color via the COLORTERM environment variable.

(Bug#41846)

Copyright-paperwork-exempt: yes

* src/term.c (encode_terminal_code): Each character from an
automatic composition is a multibyte character, so its multibyte
representation can take up to MAX_MULTIBYTE_LENGTH bytes.
Account for that when allocating storage for characters to be
encoded.  (Bug#40913)

* src/term.c (handle_one_term_event): Call tty_handle_tab_bar_click.

* src/xdisp.c (tty_handle_tab_bar_click): Force reset of up_modifier bit
from the event modifiers.

* lisp/tab-line.el (tab-line-tab-current): No need to use inverse-video
on console/xterm because the selected tab already uses inverse-video.

Run "TZ=UTC0 admin/update-copyright $(git ls-files)".

* src/dispnew.c (handle_window_change_signal, init_display_interactive):
* src/frame.c (make_terminal_frame, Fmake_terminal_frame):
* src/keyboard.c (Fsuspend_emacs):
* src/term.c (Fresume_tty):
* src/xterm.c (x_check_fullscreen):
Subtract FRAME_TAB_BAR_LINES.

* src/xterm.c (x_new_font): Set FRAME_TAB_BAR_HEIGHT.
(x_new_font, x_check_fullscreen, x_set_window_size_1)
(x_set_window_size, x_wm_set_size_hint): Add FRAME_TABBAR_HEIGHT.

Most of the directives were wrong anyway.  Apparently
traditional lint hasn’t been used to check Emacs for years.
* src/callint.c (Finteractive):
* src/cm.c (evalcost):
* src/emacs.c (main):
* src/eval.c (call1, call2, call3, call4, call5, call6, call7, call8):
* src/fns.c (concat2, concat3, nconc2):
* src/term.c (calculate_ins_del_char_costs):
Omit ARGSUSED comments.
* src/eval.c (call1): Omit VARARGS comment.

Allow 'mouse-drag-and-drop-region' to move/copy text from one
frame to another (Bug#28620).  Prevent mouse avoidance mode from
interfering with 'mouse-drag-and-drop-region' (Bug#36269).

* lisp/avoid.el (mouse-avoidance-ignore-p): Suspend avoidance
when 'track-mouse' equals 'dropping'.
* lisp/mouse.el (mouse-drag-and-drop-region): Set
'track-mouse' to 'dropping'.  Continue reading events also
when switching frames.
* src/keyboard.c (Finternal_track_mouse): Rename from
Ftrack_mouse.
(some_mouse_moved): Return NULL also when mouse is not tracked.
(show_help_echo, readable_events, kbd_buffer_get_event): Don't
check whether mouse is tracked, some_mouse_moved does it now.
(track_mouse): Rename variable from do_mouse_tracking.  Adjust
all users.  In doc-string explain meanings of special values
'dragging' and 'dropping'.
* src/nsterm.m (ns_mouse_position): During drag and drop
consider last mouse frame only when there is no currently
focused frame.
* src/w32fns.c (w32_wnd_proc): Don't set mouse capture during a
drag and drop operation.
* src/w32term.c (w32_mouse_position): Track frame under mouse
during mouse drag and drop.
(mouse_or_wdesc_frame): New function.
(w32_read_socket): Call mouse_or_wdesc_frame on mouse events.
* src/xdisp.c (define_frame_cursor1): Don't change mouse cursor
shape during mouse drag and drop.
(syms_of_xdisp): New symbol Qdropping.
* src/xterm.c (XTmouse_position): Allow mouse drag and drop move
to another frame
(mouse_or_wdesc_frame): New function.
(handle_one_xevent): Use mouse_or_wdesc_frame for mouse events.

* src/alloc.c, src/bidi.c, src/emacs-module.c, src/pdumper.c:
* src/regex-emacs.c, src/unexhp9k800.c, src/unexmacosx.c:
* src/widget.c, src/xdisp.c, src/xselect.c, src/xterm.c:
Include sysstdio.h instead of stdio.h, to avoid locking
stdio streams in many cases.
* src/alloc.c (test_setjmp):
* src/bidi.c (bidi_dump_cached_states):
* src/cm.c (calccost):
* src/dispnew.c (init_display_interactive):
* src/emacs.c (main):
* src/image.c (convert_mono_to_color_image):
* src/minibuf.c (read_minibuf_noninteractive):
* src/nsfont.m (ns_descriptor_to_entity)
(ns_dump_glyphstring):
* src/nsterm.h (NSTRACE_MSG_NO_DASHES):
* src/nsterm.m (ns_mouse_position)
(sendEvent:, keyDown:, performDragOperation:):
* src/pdumper.c (dump_fingerprint, print_paths_to_root_1):
* src/print.c (debug_print):
* src/regex-emacs.c (debug_putchar, print_fastmap)
(print_partial_compiled_pattern, print_compiled_pattern)
(print_double_string, regex_compile):
* src/term.c (vfatal):
* src/unexhp9k800.c (read_header):
* src/unexmacosx.c (unexec_error):
* src/widget.c (EmacsFrameInitialize):
* src/xdisp.c (message_to_stderr, vmessage, dump_glyph_row)
(Fdump_glyph_matrix, Fdump_frame_glyph_matrix, dump_glyph_string):
* src/xfaces.c (Fdump_colors, Fdump_face):
* src/xselect.c (x_clipboard_manager_error_2):
* src/xterm.c (x_initialize):
* src/xwidget.c (WEBKIT_FN_INIT):
Prefer unlocked calls like fputs to locked calls like fprintf.
* src/charset.c (read_hex):
* src/cm.c (cmputc, cmcheckmagic):
* src/dispnew.c (update_frame, update_frame_with_menu)
(update_frame_1, Fsend_string_to_terminal, Fding)
(bitch_at_user):
* src/emacs.c (main, Fdump_emacs):
* src/emacs-module.c (module_abort):
* src/fileio.c (Fdo_auto_save):
* src/image.c (slurp_file)
(png_read_from_file, png_load_body, our_stdio_fill_input_buffer):
* src/keyboard.c (record_char, kbd_buffer_get_event)
(handle_interrupt):
* src/lread.c (readbyte_from_stdio, read1):
* src/minibuf.c (read_minibuf_noninteractive):
* src/print.c (printchar_to_stream, strout)
(Fredirect_debugging_output):
* src/sysdep.c (reset_sys_modes, close_output_streams)
(procfs_ttyname, procfs_get_total_memory):
* src/term.c (tty_ring_bell, tty_send_additional_strings)
(tty_set_terminal_modes, tty_reset_terminal_modes)
(tty_update_end, tty_clear_end_of_line, tty_write_glyphs)
(tty_write_glyphs_with_face, tty_insert_glyphs)
(tty_menu_activate):
* src/xfaces.c (Fx_load_color_file):
Simplify by using ordinary calls like putc to explicitly-unlocked
calls like putc_unlocked, since the ordinary calls are now
unlocked anyway.
* src/emacs.c (main, Fdump_emacs):
* src/pdumper.c (Fdump_emacs_portable):
Coalesce adjacent printfs.
* src/nsterm.h: Include sysstdio.h as this file’s macros rely on it.
* src/regex-emacs.c (print_compiled_pattern):
Omit redundant fflush.
* src/sysstdio.h: Include unlocked-io.h.
(clearerr_unlocked, feof_unlocked, ferror_unlocked)
(fflush_unlocked, fgets_unlocked, fputc_unlocked)
(fputs_unlocked, fread_unlocked, fwrite_unlocked)
(getc_unlocked, getchar_unlocked, putc_unlocked)
(putchar_unlocked): Remove these macros; now done by unlocked-io.h.
* src/xwidget.c: Include sysstdio.h.