Index: phlib/include/phbase.h
===================================================================
--- phlib/include/phbase.h	(revision 4085)
+++ phlib/include/phbase.h	(working copy)
@@ -3086,6 +3086,31 @@
     __in_opt ULONG Mode
     );
 
+// strpool
+
+typedef struct _PH_STRING_POOL
+{
+    PH_QUEUED_LOCK Lock;
+    PPH_HASHTABLE Hashtable;
+} PH_STRING_POOL, *PPH_STRING_POOL;
+
+VOID
+PhInitializeStringPool(
+    __out PPH_STRING_POOL Pool,
+    __in ULONG InitialCapacity
+    );
+
+VOID
+PhDeleteStringPool(
+    __in PPH_STRING_POOL Pool
+    );
+
+PPH_STRING
+PhInternStringPool(
+    __inout PPH_STRING_POOL Pool,
+    __in __assumeRefs(1) PPH_STRING String
+    );
+
 // format
 
 VOID
Index: phlib/phlib.vcxproj
===================================================================
--- phlib/phlib.vcxproj	(revision 4085)
+++ phlib/phlib.vcxproj	(working copy)
@@ -215,6 +215,7 @@
     <ClCompile Include="secdata.c" />
     <ClCompile Include="secedit.c" />
     <ClCompile Include="sha.c" />
+    <ClCompile Include="strpool.c" />
     <ClCompile Include="support.c" />
     <ClCompile Include="svcsup.c" />
     <ClCompile Include="symprv.c" />
Index: phlib/phlib.vcxproj.filters
===================================================================
--- phlib/phlib.vcxproj.filters	(revision 4085)
+++ phlib/phlib.vcxproj.filters	(working copy)
@@ -201,6 +201,9 @@
     <ClCompile Include="workqueue.c">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="strpool.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="include\phsync.h">
Index: ProcessHacker/ProcessHacker.vcxproj
===================================================================
--- ProcessHacker/ProcessHacker.vcxproj	(revision 4085)
+++ ProcessHacker/ProcessHacker.vcxproj	(working copy)
@@ -250,6 +250,7 @@
     <ClCompile Include="..\phlib\secdata.c" />
     <ClCompile Include="..\phlib\secedit.c" />
     <ClCompile Include="..\phlib\sha.c" />
+    <ClCompile Include="..\phlib\strpool.c" />
     <ClCompile Include="..\phlib\support.c" />
     <ClCompile Include="..\phlib\svcsup.c" />
     <ClCompile Include="..\phlib\symprv.c" />
Index: ProcessHacker/ProcessHacker.vcxproj.filters
===================================================================
--- ProcessHacker/ProcessHacker.vcxproj.filters	(revision 4085)
+++ ProcessHacker/ProcessHacker.vcxproj.filters	(working copy)
@@ -432,6 +432,9 @@
     <ClCompile Include="phsvc\clapi.c">
       <Filter>phsvc</Filter>
     </ClCompile>
+    <ClCompile Include="..\phlib\strpool.c">
+      <Filter>phlib</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="..\phlib\circbuf_i.h">
Index: phlib/strpool.c
===================================================================
--- phlib/strpool.c	(revision 0)
+++ phlib/strpool.c	(revision 0)
@@ -0,0 +1,134 @@
+/*
+ * Process Hacker - 
+ *   string pool
+ * 
+ * Copyright (C) 2011 wj32
+ * 
+ * This file is part of Process Hacker.
+ * 
+ * Process Hacker is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Process Hacker is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Process Hacker.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <phbase.h>
+
+BOOLEAN PhpStringPoolHashtableCompareFunction(
+    __in PVOID Entry1,
+    __in PVOID Entry2
+    );
+
+ULONG PhpStringPoolHashtableHashFunction(
+    __in PVOID Entry
+    );
+
+VOID PhInitializeStringPool(
+    __out PPH_STRING_POOL Pool,
+    __in ULONG InitialCapacity
+    )
+{
+    PhInitializeQueuedLock(&Pool->Lock);
+    Pool->Hashtable = PhCreateHashtable(
+        sizeof(PPH_STRING),
+        PhpStringPoolHashtableCompareFunction,
+        PhpStringPoolHashtableHashFunction,
+        InitialCapacity
+        );
+}
+
+VOID PhDeleteStringPool(
+    __in PPH_STRING_POOL Pool
+    )
+{
+    PH_HASHTABLE_ENUM_CONTEXT enumContext;
+    PPH_STRING *string;
+
+    PhBeginEnumHashtable(Pool->Hashtable, &enumContext);
+
+    while (string = PhNextEnumHashtable(&enumContext))
+    {
+        PhDereferenceObject(string);
+    }
+
+    PhDereferenceObject(Pool->Hashtable);
+}
+
+BOOLEAN PhpStringPoolHashtableCompareFunction(
+    __in PVOID Entry1,
+    __in PVOID Entry2
+    )
+{
+    PPH_STRING string1 = *(PPH_STRING *)Entry1;
+    PPH_STRING string2 = *(PPH_STRING *)Entry2;
+
+    return PhEqualString(string1, string2, FALSE);
+}
+
+ULONG PhpStringPoolHashtableHashFunction(
+    __in PVOID Entry
+    )
+{
+    PPH_STRING string = *(PPH_STRING *)Entry;
+
+    return PhHashBytes((PUCHAR)string->Buffer, string->Length);
+}
+
+PPH_STRING PhInternStringPool(
+    __inout PPH_STRING_POOL Pool,
+    __in __assumeRefs(1) PPH_STRING String
+    )
+{
+    PPH_STRING string;
+    PPH_STRING *realEntry;
+    BOOLEAN added;
+    PPH_STRING needsDereference;
+
+    needsDereference = NULL;
+
+    PhAcquireQueuedLockExclusive(&Pool->Lock);
+
+    realEntry = PhAddEntryHashtableEx(
+        Pool->Hashtable,
+        &String,
+        &added
+        );
+
+    if (added)
+    {
+        // First entry with this string, so return what the caller gave us.
+        string = String;
+        // We also need an extra reference for storage.
+        PhReferenceObject(String);
+    }
+    else
+    {
+        string = *realEntry;
+
+        if (string != String)
+        {
+            // We need an extra reference for the caller.
+            PhReferenceObject(string);
+            // The entry is already in the hashtable, but the caller gave 
+            // us a string we don't need anymore.
+            // Note that we dereference outside of the lock to avoid 
+            // potential deadlocks involving delete procedures and hooks.
+            needsDereference = String;
+        }
+    }
+
+    PhReleaseQueuedLockExclusive(&Pool->Lock);
+
+    if (needsDereference)
+        PhDereferenceObject(needsDereference);
+
+    return string;
+}