imsg_read() will call recvmsg() on the file descriptor regardless of the read buffer's state, so we should ensure that data is ready. The read buffer is used by imsg_get(), not imsg_read(). We already call imsg_get() before imsg_read(), and call the latter only if imsg_get() returns zero.

This speeds up loading of trees significantly. ok op@

Avoids some extra malloc/free in a performance-critical path. ok op@

no functional change

let got_patch own fileindex_path and call got_worktree_patch_complete only if got_wokrtree_patch_prepare hasn't failed. suggested by stsp@

Instead of flushing the fileindex after every patch in the patchfile just reuse the same fileindex and sync it only at the end of the patch operation. This speeds up 'got patch' on large repositories by quite a lot.

ok op