libunwind is reentrant and signal safe, and works faster then then
gcc_eh (plus it has some custom patches for problems that have been
found during it's usage in ClickHouse).
gcc_eh may be missing in the system (if gcc was not installed), and
even if it exists clickhouse uses -nodefaultlibs, so some care should be
made to make it work.
Also this library is tiny and there shouln't be any problem to require
it always (there is already tendency to require some contrib libraries,
i.e. poco).
Signed-off-by: Azat Khuzhin <a.khuzhin@semrush.com>
Follow-up to #38456
The problem was that code which uses liburing was conditionally build
depending on define OS_LINUX and not based on whether liburing was
enabled/disabled at build time.
Note, that it can the fail the client if the skim itself will fail,
however I haven't seen it panicd, so let's try.
P.S. about adding USE_SKIM into configure header instead of just compile
option for target, it is better, because it allows not to recompile lots
of C++ headers, since we have to add skim library as PUBLIC. But anyway
this will be resolved in a different way, but separatelly.
Signed-off-by: Azat Khuzhin <a.khuzhin@semrush.com>
Note, that it can the fail the client if the skim itself will fail,
however I haven't seen it panicd, so let's try.
P.S. about adding USE_SKIM into configure header instead of just compile
option for target, it is better, because it allows not to recompile lots
of C++ headers, since we have to add skim library as PUBLIC.
Signed-off-by: Azat Khuzhin <a.khuzhin@semrush.com>
* Add a codec Encrypted() for encrypting columns on disk
While this is implemented as a compression codec, it does not actually compress data. It instead encrypts data on disk. The key is obtained by executing a user-specified command at the server startup, or if it's not specified the codec refuses to process any data. For now the only supported cipher is 'AES-128-GCM-SIV'.
