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 file-saving procedure that nano followed was not crash-safe
under ext4 (and perhaps other filesystems) when editing existing
files. Specifically, modifying an existing file could lead to data
loss, since a modified file is not replaced atomically on disk.
Using "-B" did not ensure crash-safety either since the backup might
not have persisted on disk when the writeout of the file started.
In addition, if I/O pressure filled up the remaining disk space
after an existing file is truncated during save, nano would not
be able to finish saving the file, which would remain truncated.
This change addresses these issues by making nano do the following:
1) Make a temporary backup of the file being written so that there
is no time window such that (a) an existing file is truncated, and
(b) the buffer corresponding to said file has not been flushed to
disk. Such time windows are dangerous because, under certain
circumstances, they can lead to data loss on some filesystems.
The backup is made by copying the original file, and a second
attempt to HOME is made in case that first copy fails.
2) Use fsync() so that, when the save finishes, it is certain
that the file has been successfully written to disk.
This addresses https://savannah.gnu.org/bugs/?58642.
Signed-off-by: Michalis Kokologiannakis <michalis@mpi-sws.org>
Especially when it are just a handful of possible completions, it is
much nicer to have them listed close to the prompt bar where the eyes
of the user are.
This fulfills https://savannah.gnu.org/bugs/?58620.
This gives quicker feedback, and spares the user unnecessary beeps
and typing. Also, now a beep after a <Tab> means just one thing:
there are NO completions.
This fulfills https://savannah.gnu.org/bugs/?58627.
The parameter was referenced in just one place. So, simply check for
the three relevant menus (and unrestricted mode) and be done with it.
This also has the pleasant effect that the menu name is now the first
parameter of do_prompt(), thus clearly indicating what prompt it is,
instead of having an opaque TRUE or FALSE value at the beginning.
Tabbing can list all files in the given directory, but restricted mode
is supposed to prevent the user from any access to the filesystem...
This fixes https://savannah.gnu.org/bugs/?58632.
Bug existed (in this form) since version 1.3.4, commit f7b5d930.
Instead of burdening seven other calls of do_prompt() with a useless
parameter, just check for MGOTODIR in the appropriate place. It also
saves having to pass the parameter down through three more functions.
The single dot serves no purpose, as the user is already there. And
the double dot is reached more easily by typing a second dot first.
And anyway, . and .. are not shown when the user does not type a dot
first, so why show them when the user types a single dot followed by
<Tab><Tab>? Most likely the user wants to see actual dot files, so
just show those.
This fixes https://savannah.gnu.org/bugs/?58619.
The username_tab_completion() function taken from busybox-0.46 was
just a stub, it contained basically nothing. Chris himself wrote
the function in November 2000 (commit be77c611), and rewrote it in
January 2001 (commit 2c2c5f21).
The version of username_tab_completion() in that latter commit looks
somewhat like the version of Vladimir N. Oleynik <dzo@simtreas.ru>
(busybox commit 4e338757). That commit comes three days after Chris'
commit, but Vladimir's original email is from a week earlier:
http://lists.busybox.net/pipermail/busybox/2001-January/035687.html.
So... it is quite possible that Rocco saw that email and suggested
to Chris to rewrite username_tab_completion() using getpwent().
Anyway, the version that was taken from busybox-0.46 was just four
lines and thus not worthy of copyright. The two other functions
that were copied were heavily modified in 2000, so it's better to
add that year in the copyright notice. It is fine to tweak the
notice: it just says that the original authors must be attributed,
not that the exact text must remain unchanged.
Instead of first trying to match things, and then discarding these
matches when the cursor is not at the end of the offered fragment
('buf'), simply don't bother to do any matching in that case.
The variable is set to zero at its declaration, and the second function
is called only when the first is either not called or found nothing --
thus '*num_matches' will still be zero.
Having the M-F toggle non-persistent, makes the behavior of ^R
predictable. This allows string binds that load a file to work
correctly independently of when M-F was last pressed.
The -F/--multibuffer command-line option and "set multibuffer"
in a nanorc file determine the default behavior of ^R.
Signed-off-by: Marco Diego Aurélio Mesquita <marcodiegomesquita@gmail.com>
Each listing of a name is preceeded by a call to wmove(), so there
is no need for an initial wmove(). And after writing "more" on the
bottom row of the edit window, the loop is terminated, so there is
no need to check that this is the first item on the bottom row.
And when the margin changes (when line numbers are switched on or off,
or when the buffer grows or shrinks), and when a piece of text from a
different buffer with a different margin is pasted.
This fixes https://savannah.gnu.org/bugs/?58517.
Bug existed since commit 9a9f36fc from yesterday.
Instead of storing for each line the ordinal number of the first chunk
in that line, simply store the number of extra chunks in the line.
It now takes some more computation to actually draw the scrollbar, but
it saves a lot of computation when just inserting or deleting characters
(when using --softwrap and causing a change in chunk count).
This fixes https://savannah.gnu.org/bugs/?58510.
Bug existed since commit 6bccedb3 from two days ago.
Make the "Execute Command" menu accessible also with a single keystroke
(^T), not just with a double one (^R^X). This is useful, because no one
will suspect that "Execute Command" can be found behind "Read File".
To not disturb muscle memory too much for people who are used to ^T
invoking the Spell Checker, a second ^T will invoke it.
Instead of creating a special Tools menu, add the five functions that
affect the whole buffer to the "Execute Command" menu. There is room
for these five functions there, and they kind of fit in because three
of them (Speller, Linter, and Formatter) actually invoke an external
command, and Full Justify could have been implemented externally, and
the destructive Cut Till End ought to have required a double keystroke
since the beginning.
Also, do not prompt when there is no space left on the device,
because then trying to save the actual file would likely lead
to truncating it, resulting in an empty file.
Only when fclose() is called, does the data get flushed out to disk,
and maybe only then the system realizes that there is no space left on
the device, as Chris noted in: https://savannah.gnu.org/bugs/?24000.
When asking this question when deleting fails or writing fails,
it should be asked too when creating fails. Otherwise the user
is blocked from saving the file -- until she realizes that maybe
toggling off backups would help.
If the user answered "No" or "Cancel" the first time, they should
be allowed to answer "Yes" the next time -- possibly after fixing
the necessary permissions in another terminal.
This fixes https://savannah.gnu.org/bugs/?58442.
Bug existed since version 2.3.0, commit 3d411188.
