cache.cpp keeps its C API but replaces uthash and the two mallocs per
entry with one slab of nodes holding their keys inline, linked in
last-use order, and an open-addressing index of node ids that hashes
through the slab with a per-cache random seed. Both blocks are reserved
by cache_create() and touched only as entries are used, so a large,
mostly empty cache costs no resident memory.
Semantics are unchanged: an insert evicts the least recently used entry
once the cache holds capacity entries (the AEAD-2022 session table's
4095/4096 boundary), lookups refresh recency and age, cache_clear()
drops stale entries, and free_cb may re-enter the cache. Re-inserting a
key now replaces its data instead of shadowing it. cache_create_keyed()
sizes keys per cache; the AEAD-2022 salt pool and session table use it.
test_cache_cpp covers the boundary, ordering, replacement, ageing,
re-entrant callbacks and limits; alloc_steady_cache requires zero
allocations across 100,000 inserts on a full cache. AEAD-2022 ss-server
drops from 84 to 80 allocations per relayed connection.
Rename base64, json, ipset, process, ppbloom, rule, ssurl and cache from
.c to .cpp without touching their contents, and update the CMake source
lists, debian/copyright and the docs.
Ported code keeps -Wall; -Wextra is now opt-in through
ss_strict_warnings() for code written as C++ (the core tests).
check_no_heap.py gains a ratchet baseline for the converted modules,
which still allocate the way the C code did. A new check_cxx_runtime
test verifies with nm that the programs and libshadowsocks-c.a still
need no C++ runtime library, so C consumers are unaffected.
Max Lv