The escape-parsing routine nowadays returns FOREIGN_SEQUENCE instead
of ERR when encountering an unknown sequence. So, with the two cases
that demand ERR now handled directly, there is no need to check for
ERR any more.
There is no need to reset the digit counter (because this counter
matters only when the escape counter equals two) -- resetting the
escape counter is enough.
The digit counter will be reset to zero the next time when <Esc>
is pressed, and the byte holder gets re-initialized when the next
first digit is pressed. And the escape counter is reset to zero
after returning from a result-giving call of get_byte_kbinput().
When get_byte_kbinput() is called, it has already been determined that
the keyboard input is a digit from zero to nine (or from zero to two
for the first digit), so there is no need to check this again.
When <Esc><Esc> is followed by digit 0 or 1 or 2 but then NOT two more
digits follow, then both the escape counter and the digit counter should
start afresh when a new ESC code arrives.
This fixes https://savannah.gnu.org/bugs/?58788.
Bug existed since before version 2.0.6.
Root has carte blanche to both read unreadable files and write
unwritable files -- the file system does not prevent this. So,
alert root when opening a file that is intended to be read-only.
This fulfills https://savannah.gnu.org/bugs/?58685.
Requested-by: Marius Bakke <mbakke@fastmail.com>
Also, remove an unneeded 'if', as parse_escape_sequence() is only
ever called when there are at least two bytes after the Esc code.
(If there were not, the 'for' loop after calling convert_sequence()
would use an uninitialized 'consumed' value.)
Rereading is unlikely to fail, but *if* it fails, maybe there is a
serious problem and the user wants to try and fix it before saving
the buffer and thus overwriting the original file.
After thinking about it, I don't like it that nano makes an unrequested
failsafe backup: in the vast, vast majority of cases it is a waste both
of time and of disk wear. If the user is worried about data loss, they
can use --backup. The fsync() after writing out the buffer (added in
commit a84cdaaa) already reduces the chances on data loss somewhat.
This change moves the code responsible for backup creation to a new,
separate function, backup_file(). This function returns a boolean
indicating whether saving the buffer should proceed or not.
Signed-off-by: Michalis Kokologiannakis <michalis@mpi-sws.org>
The escape-sequence codes for the different keypad keys are simply
the relevant ASCII code plus 0x40, so they are easy to translate.
Also, do not accept keypad keys with multiple modifiers (Shift+Alt,
Shift+Ctrl, Alt+Ctrl, Shift+Alt+Ctrl) -- report "Unknown sequence"
for those.
Until now, on an xterm, Shift plus any keypad key would say
"Unknown sequence", which is not useful. On other terminal
emulators (urxvt, Pantheon, LXTerminal), Shift plus a keypad
key already produces the relevant digit or symbol, so this
change harmonizes the behavior of the different emulators.
However, on a Linux console, Shift plus a keypad key moves
the cursor and selects the text that is passed over. And
holding Alt while pressing a keypad key does nothing at all.
For the operator keys on the numeric keypad (/, *, -, and +),
make both the Alt and the Ctrl modifier a no-op.
This fixes https://savannah.gnu.org/bugs/?58731.
Bug existed since version 2.9.3, commit e734488c.