Fix the presence info caching used in llRequestAgentData(), which was completely inoperative.

This means the presence info may be out of date by up to 20 seconds, but this avoids scripts potentially triggering constants requests to user accout and presence info services.
Relates to http://opensimulator.org/mantis/view.php?id=7088 though I fixed in a different way.
Adds regression test for this case.

3 files changed, 92 insertions, 59 deletions

diff --git a/OpenSim/Data/Null/NullPresenceData.cs b/OpenSim/Data/Null/NullPresenceData.cs
index b85b95e..aff0b0b 100644
--- a/OpenSim/Data/Null/NullPresenceData.cs
+++ b/OpenSim/Data/Null/NullPresenceData.cs
@@ -40,7 +40,7 @@ namespace OpenSim.Data.Null
     {
 //        private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
         
-        private static NullPresenceData Instance;
+        public static NullPresenceData Instance;
 
         Dictionary<UUID, PresenceData> m_presenceData = new Dictionary<UUID, PresenceData>();
 
diff --git a/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs b/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs
index e38394a..a9f5541 100644
--- a/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs
@@ -87,6 +87,8 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
     {
         private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
 
+        public int LlRequestAgentDataCacheTimeoutMs { get; set; }
+
         protected IScriptEngine m_ScriptEngine;
         protected SceneObjectPart m_host;
 
@@ -160,30 +162,44 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
         /// </summary>
         private void LoadConfig()
         {
-            m_ScriptDelayFactor =
-                m_ScriptEngine.Config.GetFloat("ScriptDelayFactor", 1.0f);
-            m_ScriptDistanceFactor =
-                m_ScriptEngine.Config.GetFloat("ScriptDistanceLimitFactor", 1.0f);
-            m_MinTimerInterval =
-                m_ScriptEngine.Config.GetFloat("MinTimerInterval", 0.5f);
-            m_automaticLinkPermission =
-                m_ScriptEngine.Config.GetBoolean("AutomaticLinkPermission", false);
-            m_notecardLineReadCharsMax =
-                m_ScriptEngine.Config.GetInt("NotecardLineReadCharsMax", 255);
+            LlRequestAgentDataCacheTimeoutMs = 20000;
+
+            IConfig seConfig = m_ScriptEngine.Config;
+
+            if (seConfig != null)
+            {
+                m_ScriptDelayFactor =
+                    seConfig.GetFloat("ScriptDelayFactor", m_ScriptDelayFactor);
+                m_ScriptDistanceFactor =
+                    seConfig.GetFloat("ScriptDistanceLimitFactor", m_ScriptDistanceFactor);
+                m_MinTimerInterval =
+                    seConfig.GetFloat("MinTimerInterval", m_MinTimerInterval);
+                m_automaticLinkPermission =
+                    seConfig.GetBoolean("AutomaticLinkPermission", m_automaticLinkPermission);
+                m_notecardLineReadCharsMax =
+                    seConfig.GetInt("NotecardLineReadCharsMax", m_notecardLineReadCharsMax);
+
+                // Rezzing an object with a velocity can create recoil. This feature seems to have been
+                //    removed from recent versions of SL. The code computes recoil (vel*mass) and scales
+                //    it by this factor. May be zero to turn off recoil all together.
+                m_recoilScaleFactor = m_ScriptEngine.Config.GetFloat("RecoilScaleFactor", m_recoilScaleFactor);
+            }
+
             if (m_notecardLineReadCharsMax > 65535)
                 m_notecardLineReadCharsMax = 65535;
 
             // load limits for particular subsystems.
-            IConfig SMTPConfig;
-            if ((SMTPConfig = m_ScriptEngine.ConfigSource.Configs["SMTP"]) != null) {
-                // there's an smtp config, so load in the snooze time.
-                EMAIL_PAUSE_TIME = SMTPConfig.GetInt("email_pause_time", EMAIL_PAUSE_TIME);
-            }
+            IConfigSource seConfigSource = m_ScriptEngine.ConfigSource;
 
-            // Rezzing an object with a velocity can create recoil. This feature seems to have been
-            //    removed from recent versions of SL. The code computes recoil (vel*mass) and scales
-            //    it by this factor. May be zero to turn off recoil all together.
-            m_recoilScaleFactor = m_ScriptEngine.Config.GetFloat("RecoilScaleFactor", m_recoilScaleFactor);
+            if (seConfigSource != null)
+            {
+                IConfig smtpConfig = seConfigSource.Configs["SMTP"];
+                if (smtpConfig != null) 
+                {
+                    // there's an smtp config, so load in the snooze time.
+                    EMAIL_PAUSE_TIME = smtpConfig.GetInt("email_pause_time", EMAIL_PAUSE_TIME);
+                }
+            }
         }
 
         public override Object InitializeLifetimeService()
@@ -4196,60 +4212,71 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
             UserAccount account;
 
             UserInfoCacheEntry ce;
-            if (!m_userInfoCache.TryGetValue(uuid, out ce))
+
+            lock (m_userInfoCache)
             {
-                account = World.UserAccountService.GetUserAccount(World.RegionInfo.ScopeID, uuid);
-                if (account == null)
+                if (!m_userInfoCache.TryGetValue(uuid, out ce))
                 {
-                    m_userInfoCache[uuid] = null; // Cache negative
-                    return UUID.Zero.ToString();
-                }
-
+                    account = World.UserAccountService.GetUserAccount(World.RegionInfo.ScopeID, uuid);
+                    if (account == null)
+                    {
+                        m_userInfoCache[uuid] = null; // Cache negative
+                        return UUID.Zero.ToString();
+                    }
 
-                PresenceInfo[] pinfos = World.PresenceService.GetAgents(new string[] { uuid.ToString() });
-                if (pinfos != null && pinfos.Length > 0)
-                {
-                    foreach (PresenceInfo p in pinfos)
+                    PresenceInfo[] pinfos = World.PresenceService.GetAgents(new string[] { uuid.ToString() });
+                    if (pinfos != null && pinfos.Length > 0)
                     {
-                        if (p.RegionID != UUID.Zero)
+                        foreach (PresenceInfo p in pinfos)
                         {
-                            pinfo = p;
+                            if (p.RegionID != UUID.Zero)
+                            {
+                                pinfo = p;
+                            }
                         }
                     }
-                }
 
-                ce = new UserInfoCacheEntry();
-                ce.time = Util.EnvironmentTickCount();
-                ce.account = account;
-                ce.pinfo = pinfo;
-            }
-            else
-            {
-                if (ce == null)
-                    return UUID.Zero.ToString();
-
-                account = ce.account;
-                pinfo = ce.pinfo;
-            }
+                    ce = new UserInfoCacheEntry();
+                    ce.time = Util.EnvironmentTickCount();
+                    ce.account = account;
+                    ce.pinfo = pinfo;
 
-            if (Util.EnvironmentTickCount() < ce.time || (Util.EnvironmentTickCount() - ce.time) >= 20000)
-            {
-                PresenceInfo[] pinfos = World.PresenceService.GetAgents(new string[] { uuid.ToString() });
-                if (pinfos != null && pinfos.Length > 0)
+                    m_userInfoCache[uuid] = ce;
+                }
+                else
                 {
-                    foreach (PresenceInfo p in pinfos)
+                    if (ce == null)
+                        return UUID.Zero.ToString();
+
+                    account = ce.account;
+
+                    if (Util.EnvironmentTickCount() < ce.time || (Util.EnvironmentTickCount() - ce.time) 
+                        >= LlRequestAgentDataCacheTimeoutMs)
                     {
-                        if (p.RegionID != UUID.Zero)
+                        PresenceInfo[] pinfos = World.PresenceService.GetAgents(new string[] { uuid.ToString() });
+                        if (pinfos != null && pinfos.Length > 0)
+                        {
+                            foreach (PresenceInfo p in pinfos)
+                            {
+                                if (p.RegionID != UUID.Zero)
+                                {
+                                    pinfo = p;
+                                }
+                            }
+                        }
+                        else
                         {
-                            pinfo = p;
+                            pinfo = null;
                         }
+
+                        ce.time = Util.EnvironmentTickCount();
+                        ce.pinfo = pinfo;
+                    }
+                    else
+                    {
+                        pinfo = ce.pinfo;
                     }
                 }
-                else
-                    pinfo = null;
-
-                ce.time = Util.EnvironmentTickCount();
-                ce.pinfo = pinfo;
             }
 
             string reply = String.Empty;
diff --git a/OpenSim/Tests/Common/Helpers/SceneHelpers.cs b/OpenSim/Tests/Common/Helpers/SceneHelpers.cs
index 8f44555..eb8078d 100644
--- a/OpenSim/Tests/Common/Helpers/SceneHelpers.cs
+++ b/OpenSim/Tests/Common/Helpers/SceneHelpers.cs
@@ -30,6 +30,7 @@ using System.Net;
 using System.Collections.Generic;
 using Nini.Config;
 using OpenMetaverse;
+using OpenSim.Data.Null;
 using OpenSim.Framework;
 using OpenSim.Framework.Communications;
 using OpenSim.Framework.Console;
@@ -301,6 +302,11 @@ namespace OpenSim.Tests.Common
         /// <param name="testScene"></param>
         private static LocalPresenceServicesConnector StartPresenceService()
         {
+            // Unfortunately, some services share data via statics, so we need to null every time to stop interference
+            // between tests.
+            // This is a massive non-obvious pita.
+            NullPresenceData.Instance = null;
+
             IConfigSource config = new IniConfigSource();
             config.AddConfig("Modules");
             config.AddConfig("PresenceService");