Access control lists can permit read and write access to a file
but not permit to manipulate any attributes of the file. So it
is quite possible for futimens() to fail, just like chown() and
chmod() can fail, but this should be no cause for alarm: as long
as writing the backup file worked, then writing the file itself
will probably work too.
First, it is very unlikely that chmod() would fail as the user just
created the file herself. Second, even if chmod() would fail, this
is not a problem, because we have created the file with read+write
permissions for the owner only, so the file cannot accidentally be
left accessible to unintended others.
But most of all, such a failure should not stop nano from trying to
write the backup file. Only when the actual *writing* fails, should
we bother the user with a prompt.
If there are still systems where mkstemp() creates world-readable
temporary files, then please holler. On current BSDs and on GNU,
I've verified that mkstemp() creates files with 0600 permissions.
When deleting an existing backup file failed, we do not want to
append to this file, but want instead to overwrite it (when the
user has put 'set allow_insecure_backup' in their nanorc file).
Also, when using O_EXCL (in the normal, secure case), O_APPEND
is pointless, because the file will be created and thus empty.
This fixes https://savannah.gnu.org/bugs/?58439.
Bug existed since version 2.2.5, commit 461519cc.
A normal user can change the group of a file (if the user is a member
of that group), but cannot change the owner of that file. So, when a
user edits a file that belongs to a different user, the call of fchown()
will fail. But there is no harm in that. Also when the user is root,
there is no harm in fchown() failing -- it will simply mean that the
backup file will remain owned by root and will not be writable by the
intended owner (when root has the normal umask of 0022).
This fixes https://savannah.gnu.org/bugs/?58383.
Bug existed since version 2.2.5, commit 86be3af7.
If unlinking would fail because the parent directory is unwritable,
then a check in has_valid_path() would have prevented do_lockfile()
from being called at all.
If in between the unlink() in delete_lockfile() and the fopen() in
write_lockfile() some other process creates a symlink in the place
of the lock file, then the fopen() could unexpectedly overwite a
root-owned file (when the user is root).
This basically reverts the previous commit, b4299f4f, but makes the
code a bit conciser.
One microsecond earlier, the lock file has been deleted (if it existed),
so, if between our unlink() and our open() some other process managed to
recreate the lock file... well, we want to delete it *again*. So, just
overwrite and truncate the lock file (if it exists).
When the lock file did NOT exist (a few microseconds earlier, when
checking in do_lockfile(), before calling write_lockfile()), then
the user expects the lock file to be written, so: just write it.
That between the check and the actual writing of the lock file there
is a small window of opportunity for other processes to write this
lock file is unfortunate, but it is not a reason to bother the user
with an error message when it happens.
One microsecond before a lock file is created an existing lock file
has been deleted, and if that deletion failed, writing the lock file
is aborted. So why should writing the lock file not be aborted when
the lock file cannot be exclusively created one microsecond later?
This makes no sense. So... always include the O_EXCL flag, also
when the INSECURE_BACKUP flag is set.
(And anyway: lock files are not an essential part of editing, they
are just a small service to the user, AND they have nothing to do
with backups, so a backup flag should not influence them.)
A file is always in either Unix or DOS or Mac format, and should
by default be saved again in that same format.
Any lone CRs or LFs after the first line should not change the
format that was deduced from that very first line.
Only when a CR is seen before any LF, and the CR is not followed
by a LF, should this CR be interpreted as a line separator. And
only then the file should be reported as being in Mac format --
as long as --noconvert is not used.
This fixes https://savannah.gnu.org/bugs/?58357.
Bug existed since at least version 2.0.6.
When the user mentions the file "zzy" on the command line,
the magic spell "Xyzzy" does not actually get typed, so the
Easter egg should then not be triggered.
When a file is saved under a different name, and as a result the
applicable syntax changes, and the old syntax had multiline regexes
and the new syntax doesn't, then the call of precalc_multicolorinfo()
in write_file() should not result in nano setting up a multicache of
zero bytes for each line in the buffer.
(Problem was found by locally letting nano crash when zero bytes are
allocated, and then happening to rename a file.py to a file.sh.)
A long option should describe what it does, not vaguely hint at it.
Also, in several places of nano's code we deal with actual temp files,
and then having a flag called TEMP_FILE that doesn't have anything to
do with temp files is somewhat confusing.
Just let all anchors disappear when doing an external spell check or
formatting or piping the buffer through an external command, because
leaving just a single anchor on the top line is useless.
This fixes https://savannah.gnu.org/bugs/?58273.
Bug existed since commit 732cf887 from one month ago. That code
causes an anchor to persist at the point where lines are removed.
Its major function is to find an applicable syntax, if there is any.
And if the syntax hasn't been used before, to prime its color pairs.
Also, reshuffle a line to be able to elide an #ifdef.
Avoid having to decrement the count in order to offset the increment
at the end of the loop.
Also, declare a variable on a separate line, and rename it.
First cutting the text to be copied (before copying it back into the
buffer) had unwanted side effects: it moved the cursor, and changed
the linestructs of the current line and the line where the mark was.
[This takes thirty more lines, but the idea is to later get rid of
the partitioning routines entirely.]
This means that in most cases mark_is_before_cursor() is called twice:
once before get_region() is called, and once by get_region() itself.
This small duplication of effort is acceptable: the affected functions
are not time critical, and it makes the code shorter.
