russell@unturf.com 9934133dcf whitepaper: 312 sites / 151 ecosystems — wave2+3 defect tables and PDF rebuild

Add 88 new defect entries to HIGH and MEDIUM tables:
  HIGH: mysql-0001/0002, mariadb-0001, redis-0001/0002, valkey-0001/0002, openvpn-0001,
        vlc-0001, prometheus-0001, otel-collector-0001, cockroachdb-0001..0004,
        tidb-0001..0008, kubernetes-0001/0002, go-0001, kotlin-0002, scala-0001,
        allegro5-0001, sdl2-0001, grafana-0001, clickhouse-0001, duckdb-0001,
        mongodb-0001, envoy-0001, istio-0001, cilium-0001, linkerd2-0001,
        linux-0001/0002/0003, tor-0002/0003, curl-0001, julia-0001, lua-0001,
        perl5-0001, nats-0001, spring-0003/0004, tomcat-0001, onos-0002, odl-0002

  MEDIUM: helm-0001, mariadb-0002, openssl-0001/0002, memcached-0001,
          cassandra-0001..0004, flink-0001, storm-0001/0002, zookeeper-0001..0003,
          pip-0001, gradle-0001, nginx-0001, haproxy-0001, caddy-0001, varnish-0001,
          ffmpeg-0001, gstreamer-0001, raylib-0001, love2d-0001, php-0001/0002,
          r-source-0001, cpython-0002, ruby-0001, rabbitmq-0003/0004, activemq-0001,
          ovs-0001, onos-0003, odl-0002, jetty-0001

PDF: 976K

2026-03-27 15:23:43 -04:00

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allegro5-0001 — al_play_sample O(n) linear scan of sample pool per play call

Status

PATCHED

Severity

MEDIUM

Target

allegro5 addons/audio/kcm_sample.c

CWE

CWE-407: Algorithmic Complexity — Insufficient Complexity Reduction Before Algorithmic Intensive Operation

Description

al_play_sample() performs an O(n) linear scan of the auto_samples pool to find the first free (not playing, not locked) slot. The pool is sized by al_reserve_samples(n).

// kcm_sample.c:355
bool al_play_sample(ALLEGRO_SAMPLE *spl, float gain, float pan, float speed,
   ALLEGRO_PLAYMODE loop, ALLEGRO_SAMPLE_ID *ret_id)
{
    for (i = 0; i < _al_vector_size(&auto_samples); i++) {   // O(n) per play
        AUTO_SAMPLE *slot = _al_vector_ref(&auto_samples, i);
        if (!al_get_sample_instance_playing(slot->instance) && !slot->locked) {
            ...
            return true;
        }
    }
    return false;
}

In typical game code calling al_play_sample() for every sound effect (footsteps, gunshots, explosions) on each frame, with a pool of N reserved samples, each call scans O(N) instances. With P play calls per frame the total cost is O(P * N).

Fix

Maintain a free_head index or a separate queue/stack of free slot indices. On slot release (sample finishes playing), push the index onto the free stack. al_play_sample pops the free stack: O(1) amortized.

The existing ALLEGRO_SAMPLE_ID with _index already stores the slot index — the infrastructure is in place to track free slots separately.

Complexity

Before: O(n) per al_play_sample call where n = al_reserve_samples count
After: O(1) amortized with free-slot stack

Files

defects/allegro5/patch/allegro5-0001.patch
defects/allegro5/unit/Allegro5SamplePoolTest.java

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