Given two bitmaps and the following code:
Bitmap *a = bitmap_new(), *b = bitmap_new();
bitmap_set(a, 1);
bitmap_clear(a);
bitmap_set(a, 0);
bitmap_set(b, 0);
These two bitmaps should now have the same bits set and they should be
equal but bitmap_equal() will return false in this case because while
bitmap_clear() resets the number of elements in the array it does not
clear the array and bitmap_set() expects the array to be cleared.
GREEDY_REALLOC0 looks at the allocated size and not the actual size so
it does not clear any memory.
Fix this by freeing the allocated memory and resetting the whole Bitmap
to an initial state in bitmap_clear().
This also adds test code for this issue.
Given two bitmaps and the following code:
Bitmap *a = bitmap_new(), *b = bitmap_new();
bitmap_set(a, 0);
bitmap_unset(a, 0);
These two bitmaps should now have the same bits set and they should be
equal but bitmap_equal() will return false in this case because the
bitmaps array in a is larger because of the bit which was previously
set.
Fix this by comparing only the bits which exists in both bitmaps and
then check that the rest of the bits (if any) is all zero.
This also adds test code for this issue.
Probably a typo, checking 'ret' instead of the return value 'p'. This
might cause the function to return failure, even though it succeeded.
Furthermore, it might leak resources.
Some places invoked fflush() directly with their own manual error
checking, let's unify all that by using fflush_and_check().
This also unifies the general error paths of fflush()+rename() file
writers.
so far, when we read something from /proc/$PID we would pass on the
ENOENT from the kernel as error, if the process was missing. With this
change we systematically convert this to ESRCH, which is the more
appropriate error code, and what all the other glibc/syscalls like
kill() use.
All code that calls these functions should be fine with this change. In
fact, one invocation of get_process_exe() in bus-creds.c already assumed
ESRCH would be returned if a process is missing, and this assumption is
now validated after the change.
Virtualbox 5.0 now supports kvm hypervisor. In this case cpuid
identidies as "kvm", which breaks units depending on
ConditionVirtualization=oracle.
So return "oracle" even with kvm hypervisor.
a) use memcmp() to compare bitmaps efficiently
b) use UINT64_C() macro instead of ULL suffixes to get right suffix for
uint64_t constants
c) add a few assert()s
d) when comparing integers with 0 we generally try to make this explicit
with "!= 0".
e) remove redundant bitmap_isset() if check, as we don't have it in
bitmap_isset() either.
f) It should be fine to invoke bitmap_unset() on a NULL bitmap
No need to actually reset the bitmap, we can just truncate it back zero
size. That not only makes bitmap_clear() quicker, but also subsequent
bitmap_isclear().
Making the array static allows gcc -O2 to generate smaller code:
"size systemd" before:
text data bss dec hex filename
1377286 128608 2632 1508526 1704ae systemd
After:
text data bss dec hex filename
1374326 128572 2664 1505562 16f91a systemd
(IN_SET still results in worse generated code than using
"x == FOO || x == BAR || ...". I don't think we'll be able to match
that with the C preprocessor.)
This change limits the use of IN_SET to sets with constant elements. All
present callers use constants. The compiler would report an "initializer
element is not constant" error otherwise.
Putting the set elements in an array variable and using ELEMENTSOF makes
it clearer what's going on.
Incidentally, it also makes gcc -O2 generate slightly smaller code:
"size systemd", before:
text data bss dec hex filename
1378318 128608 2632 1509558 1708b6 systemd
After:
text data bss dec hex filename
1377286 128608 2632 1508526 1704ae systemd
Reuse the Iterator object from hashmap.h and expose a similar API.
This allows us to do
{
Iterator i;
unsigned n;
BITMAP_FOREACH(n, b, i) {
Iterator j;
unsigned m;
BITMAP_FOREACH(m, b, j) {
...
}
}
}
without getting confused. Requested by David.
We were ignoring failures from unhexchar, which meant that invalid
hex characters were being turned into garbage rather than the string
rejected.
Fix this by making unhexmem return an error code, also change the API
slightly, to return the size of the returned memory, reflecting the
fact that the memory is a binary blob,and not a string.
For convenience, still append a trailing NULL byte to the returned
memory (not included in the returned size), allowing callers to
treat it as a string without doing a second copy.
Given a container "foo", that maps user id $UID to container user, using
user namespaces, this NSS module extenstion will now map the $UID to a
name "vu-foo-$TUID" for the translated UID $UID.
Similar, userns groups are mapped to "vg-foo-$TGID" for translated GIDs
of $GID.
This simple change should make userns users more discoverable. Also,
given that many tools like "adduser" check NSS before allocating a UID,
should lower the chance of UID range conflicts between tools.
The latest consolidation cleanup of write_string_file() revealed some users
of that helper which should have used write_string_file_no_create() in the
past but didn't. Basically, all existing users that write to files in /sys
and /proc should not expect to write to a file which is not yet existant.
Merge write_string_file(), write_string_file_no_create() and
write_string_file_atomic() into write_string_file() and provide a flags mask
that allows combinations of atomic writing, newline appending and automatic
file creation. Change all users accordingly.
