Make skill result size check an assertion

Since leech uses trailing structs of two different sizes, just use the max SkillResult size in validation/zeroing and then check for overflow in a couple extra places

src/Abilities.cpp

@@ -5,8 +5,6 @@
 #include "Buffs.hpp"
 #include "Nanos.hpp"
 
-#include <assert.h>
-
 using namespace Abilities;
 
 std::map<int32_t, SkillData> Abilities::SkillTable;
@@ -56,6 +54,11 @@ static SkillResult handleSkillDamageNDebuff(SkillData* skill, int power, ICombat
     return SkillResult(sizeof(sSkillResult_Damage_N_Debuff), &result);
 }
 
+static SkillResult handleSkillLeech(SkillData* skill, int power, ICombatant* source, ICombatant* target) {
+    // TODO abilities
+    return SkillResult();
+}
+
 static SkillResult handleSkillBuff(SkillData* skill, int power, ICombatant* source, ICombatant* target) {
     BuffStack passiveBuff = {
         skill->drainType == SkillDrainType::PASSIVE ? 1 : skill->durationTime[power], // ticks
@@ -142,54 +145,59 @@ static SkillResult handleSkillResurrect(SkillData* skill, int power, ICombatant*
 #pragma endregion
 
 static std::vector<SkillResult> handleSkill(SkillData* skill, int power, ICombatant* src, std::vector<ICombatant*> targets) {
-    size_t resultSize = 0;
     SkillResult (*skillHandler)(SkillData*, int, ICombatant*, ICombatant*) = nullptr;
     std::vector<SkillResult> results;
 
     switch(skill->skillType)
     {
         case SkillType::DAMAGE:
-            resultSize = sizeof(sSkillResult_Damage);
             skillHandler = handleSkillDamage;
             break;
         case SkillType::HEAL_HP:
         case SkillType::RETURNHOMEHEAL:
-            resultSize = sizeof(sSkillResult_Heal_HP);
             skillHandler = handleSkillHealHP;
             break;
+        case SkillType::KNOCKDOWN:
+        case SkillType::SLEEP:
+        case SkillType::SNARE:
+        case SkillType::STUN:
+            skillHandler = handleSkillDamageNDebuff;
+            break;
         case SkillType::JUMP:
         case SkillType::RUN:
-        case SkillType::FREEDOM:
+        case SkillType::STEALTH:
-        case SkillType::PHOENIX:
-        case SkillType::INVULNERABLE:
         case SkillType::MINIMAPENEMY:
         case SkillType::MINIMAPTRESURE:
-        case SkillType::NANOSTIMPAK:
+        case SkillType::PHOENIX:
         case SkillType::PROTECTBATTERY:
         case SkillType::PROTECTINFECTION:
         case SkillType::REWARDBLOB:
         case SkillType::REWARDCASH:
+        // case SkillType::INFECTIONDAMAGE:
+        case SkillType::FREEDOM:
+        case SkillType::BOUNDINGBALL:
+        case SkillType::INVULNERABLE:
         case SkillType::STAMINA_SELF:
-        case SkillType::STEALTH:
+        case SkillType::NANOSTIMPAK:
-            resultSize = sizeof(sSkillResult_Buff);
+        case SkillType::BUFFHEAL:
             skillHandler = handleSkillBuff;
             break;
-        case SkillType::BATTERYDRAIN:
+        case SkillType::BLOODSUCKING:
-            resultSize = sizeof(sSkillResult_BatteryDrain);
+            skillHandler = handleSkillLeech;
-            skillHandler = handleSkillBatteryDrain;
-            break;
-        case SkillType::RECALL: // still soft lock
-        case SkillType::RECALL_GROUP: // works for player who uses it
-            resultSize = sizeof(sSkillResult_Move);
-            skillHandler = handleSkillMove;
-            break;
-        case SkillType::PHOENIX_GROUP: // broken
-            resultSize = sizeof(sSkillResult_Resurrect);
-            skillHandler = handleSkillResurrect;
             break;
         case SkillType::RETROROCKET_SELF:
             // no-op
             return results;
+        case SkillType::PHOENIX_GROUP:
+            skillHandler = handleSkillResurrect;
+            break;
+        case SkillType::RECALL:
+        case SkillType::RECALL_GROUP:
+            skillHandler = handleSkillMove;
+            break;
+        case SkillType::BATTERYDRAIN:
+            skillHandler = handleSkillBatteryDrain;
+            break;
         default:
             std::cout << "[WARN] Unhandled skill type " << (int)skill->skillType << std::endl;
             return results;
@@ -199,7 +207,7 @@ static std::vector<SkillResult> handleSkill(SkillData* skill, int power, ICombat
         assert(target != nullptr);
         SkillResult result = skillHandler(skill, power, src != nullptr ? src : target, target);
         if(result.size == 0) continue; // skill not applicable
-        if(result.size != resultSize) {
+        if(result.size > MAX_SKILLRESULT_SIZE) {
             std::cout << "[WARN] bad skill result size for " << (int)skill->skillType << " from " << (void*)handleSkillBuff << std::endl;
             continue;
         }
@@ -232,7 +240,7 @@ void Abilities::useNanoSkill(CNSocket* sock, SkillData* skill, sNano& nano, std:
     std::vector<SkillResult> results = handleSkill(skill, boost, plr, affected);
     if(results.empty()) return; // no effect; no need for confirmation packets
 
-    size_t resultSize = results.back().size; // guaranteed to be the same for every item
+    size_t resultSize = MAX_SKILLRESULT_SIZE; // lazy
     if (!validOutVarPacket(sizeof(sP_FE2CL_NANO_SKILL_USE_SUCC), results.size(), resultSize)) {
         std::cout << "[WARN] bad sP_FE2CL_NANO_SKILL_USE_SUCC packet size\n";
         return;

src/Abilities.hpp

@@ -7,18 +7,19 @@
 
 #include <map>
 #include <vector>
+#include <assert.h>
 
 constexpr size_t MAX_SKILLRESULT_SIZE = sizeof(sSkillResult_BatteryDrain);
 
 enum class SkillType {
     DAMAGE = 1,
     HEAL_HP = 2,
-    KNOCKDOWN = 3,
+    KNOCKDOWN = 3, // dnd
-    SLEEP = 4,
+    SLEEP = 4, // dnd
-    SNARE = 5,
+    SNARE = 5, // dnd
     HEAL_STAMINA = 6,
     STAMINA_SELF = 7,
-    STUN = 8,
+    STUN = 8, // dnd
     WEAPONSLOW = 9,
     JUMP = 10,
     RUN = 11,
@@ -75,6 +76,7 @@ struct SkillResult {
     size_t size;
     uint8_t payload[MAX_SKILLRESULT_SIZE];
     SkillResult(size_t len, void* dat) {
+        assert(len <= MAX_SKILLRESULT_SIZE);
         size = len;
         memcpy(payload, dat, len);
     }

src/Combat.cpp

@@ -21,6 +21,9 @@ std::map<int32_t, std::map<int8_t, Bullet>> Combat::Bullets;
 
 #pragma region Player
 bool Player::addBuff(int buffId, BuffCallback<int, BuffStack*> onUpdate, BuffCallback<time_t> onTick, BuffStack* stack) {
+    if(!isAlive())
+        return false;
+
     EntityRef self = PlayerManager::getSockFromID(iID);
 
     if(!hasBuff(buffId)) {