gnome-terminal 2.30.2 expects UTF-8 in the "OSC Ps ; Pt BEL" sequence
that sets the window title. However, XGetWMName typically returns the
title in "STRING" (Latin-1) or "COMPOUND_TEXT" (escape sequences)
encoding. Recode the title to restore it correctly. This helps
especially in the fi_FI.UTF-8 locale, where gnome-terminal has "Pääte"
as the default title.
Related to bugs 885 and 336.
When ELinks runs in an X11 terminal emulator (e.g. xterm), or in GNU
Screen, it tries to update the title of the window to match the title
of the current document. To do this, ELinks sends an "OSC 1 ; Pt BEL"
sequence to the terminal. Unfortunately, xterm expects the Pt string
to be in the ISO-8859-1 charset, making it impossible to display e.g.
Cyrillic characters. In xterm patch #210 (2006-03-12) however, there
is a menu item and a resource that can make xterm take the Pt string
in UTF-8 instead, allowing characters from all around the world.
The downside is that ELinks apparently cannot ask xterm whether the
setting is on or off; so add a terminal._template_.latin1_title option
to ELinks and let the user edit that instead.
Complete list of changes:
- Add the terminal._template_.latin1_title option. But do not add
that to the terminal options window because it's already rather
crowded there.
- In set_window_title(), take a new codepage argument. Use it to
decode the title into Unicode characters, and remove only actual
control characters. For example, CP437 has graphical characters in
the 0x80...0x9F range, so don't remove those, even though ISO-8859-1
has control characters in the same range. Likewise, don't
misinterpret single bytes of UTF-8 characters as control characters.
- In set_window_title(), do not truncate the title to the width of the
window. The font is likely to be different and proportional anyway.
But do truncate before 1024 bytes, an xterm limit.
- In struct itrm, add a title_codepage member to remember which
charset the master said it was going to use in the terminal window
title. Initialize title_codepage in handle_trm(), update it in
dispatch_special() if the master sends the new request
TERM_FN_TITLE_CODEPAGE, and use it in most set_window_title() calls;
but not in the one that sets $TERM as the title, because that string
was not received from the master and should consist of ASCII
characters only.
- In set_terminal_title(), convert the caller-provided title to
ISO-8859-1 or UTF-8 if appropriate, and report the codepage to the
slave with the new TERM_FN_TITLE_CODEPAGE request. The conversion
can run out of memory, so return a success/error flag, rather than
void. In display_window_title(), check this result and don't update
caches on error.
- Add a NEWS entry for all of this.
