This significantly speeds up the deltification step of packing by avoiding imsg traffic. gotadmin no longer requests individual raw deltas from got-read-pack to check whether it can reuse them. Instead, got-read-pack obtains a list of objects we want to pack, and hands back the list of all deltas in its pack file which can be reused. Messages are now batched such that imsg buffers are filled as much as possible. Another advantage is that deltas we are not going to reuse will no longer be written to the delta cache file, saving disk space. Before this patch, any raw delta candidate was written to the delta cache file by got-read-pack, and the decision whether to reuse the delta happened afterwards in the gotadmin process. Code for reading individual raw deltas is now unused and could be removed at some point. ok op@

This reduces memory and disk space consumption during packing. with tweaks + memleak on error fix from op@ ok op@

Saves us from doing a malloc/free call for every item on the list. ok op@

tested by thomas, naddy, and myself

landlock is a new set of linux APIs that is conceptually similar to unveil(2): the idea is to restrict what a process can do on a specified part of the filesystem. There are some differences in the behaviour: the major one being that the landlock ruleset is inherited across execve(2). This just restricts the libexec helpers by completely revoking ANY filesystem access; after all they are the biggest attack surface. got send/fetch/clone *may* end up spawning ssh(1), so at the moment is not possible to landlock the main process. From Omar Polo.

This speeds up the creation of pack files by about 30%.

This adds the capability to compile got-portable on FreeBSD.

This commit modifies the GoT main branch to be able to compile it under linux.

This saves an iteration over the entire h->offsets array when opening a pack index which should not contain large offsets in the first place. ok millert@

The singly-linked tail queue macros were added to OpenBSD 6.9 and are more widely available on other systems. ok stsp

ok millert, naddy

ok millert, naddy

POSIX says the limits defined there are available from <limits.h>, which almost all affected source files already included anyway. ok millert stsp

ok stsp