From ae7490d362e684eb52d15c4351697bfe0b0510e5 Mon Sep 17 00:00:00 2001
From: Alexandre Julliard <julliard@winehq.org>
Date: Wed, 4 Feb 2009 12:27:36 +0100
Subject: [PATCH] dbghelp: Fix pool allocation routines to be able to support
 arbitrary sizes.

Also move full arenas to a separate list to avoid searching through
them again and again.
---
 dlls/dbghelp/dbghelp_private.h | 10 +++--
 dlls/dbghelp/storage.c         | 71 +++++++++++++++++++++-------------
 2 files changed, 50 insertions(+), 31 deletions(-)

diff --git a/dlls/dbghelp/dbghelp_private.h b/dlls/dbghelp/dbghelp_private.h
index 880aed9a86b..77fb47e1320 100644
--- a/dlls/dbghelp/dbghelp_private.h
+++ b/dlls/dbghelp/dbghelp_private.h
@@ -29,6 +29,7 @@
 #include "objbase.h"
 #include "oaidl.h"
 #include "winnls.h"
+#include "wine/list.h"
 #include "wine/unicode.h"
 
 #include "cvconst.h"
@@ -37,13 +38,14 @@
 
 struct pool /* poor's man */
 {
-    struct pool_arena*  first;
-    unsigned            arena_size;
+    struct list arena_list;
+    struct list arena_full;
+    size_t      arena_size;
 };
 
-void     pool_init(struct pool* a, unsigned arena_size);
+void     pool_init(struct pool* a, size_t arena_size);
 void     pool_destroy(struct pool* a);
-void*    pool_alloc(struct pool* a, unsigned len);
+void*    pool_alloc(struct pool* a, size_t len);
 char*    pool_strdup(struct pool* a, const char* str);
 
 struct vector
diff --git a/dlls/dbghelp/storage.c b/dlls/dbghelp/storage.c
index ec8a37d7f3e..23a45e12b74 100644
--- a/dlls/dbghelp/storage.c
+++ b/dlls/dbghelp/storage.c
@@ -34,14 +34,16 @@ WINE_DEFAULT_DEBUG_CHANNEL(dbghelp);
 
 struct pool_arena
 {
-    struct pool_arena*  next;
-    char*               current;
+    struct list entry;
+    char       *current;
+    char       *end;
 };
 
-void pool_init(struct pool* a, unsigned arena_size)
+void pool_init(struct pool* a, size_t arena_size)
 {
+    list_init( &a->arena_list );
+    list_init( &a->arena_full );
     a->arena_size = arena_size;
-    a->first = NULL;
 }
 
 void pool_destroy(struct pool* pool)
@@ -50,58 +52,73 @@ void pool_destroy(struct pool* pool)
     struct pool_arena*  next;
 
 #ifdef USE_STATS
-    unsigned    alloc, used, num;
-    
+    size_t alloc, used, num;
+
     alloc = used = num = 0;
-    arena = pool->first;
-    while (arena)
+    LIST_FOR_EACH_ENTRY( arena, &pool->arena_list, struct pool_arena, entry )
     {
-        alloc += pool->arena_size;
+        alloc += arena->end - (char *)arena;
+        used += arena->current - (char*)arena;
+        num++;
+    }
+    LIST_FOR_EACH_ENTRY( arena, &pool->arena_full, struct pool_arena, entry )
+    {
+        alloc += arena->end - (char *)arena;
         used += arena->current - (char*)arena;
         num++;
-        arena = arena->next;
     }
     if (alloc == 0) alloc = 1;      /* avoid division by zero */
-    FIXME("STATS: pool %p has allocated %u kbytes, used %u kbytes in %u arenas,\n"
-          "\t\t\t\tnon-allocation ratio: %.2f%%\n",
-          pool, alloc >> 10, used >> 10, num, 100.0 - (float)used / (float)alloc * 100.0);
+    FIXME("STATS: pool %p has allocated %u kbytes, used %u kbytes in %u arenas, non-allocation ratio: %.2f%%\n",
+          pool, (unsigned)(alloc >> 10), (unsigned)(used >> 10), (unsigned)num,
+          100.0 - (float)used / (float)alloc * 100.0);
 #endif
 
-    arena = pool->first;
-    while (arena)
+    LIST_FOR_EACH_ENTRY_SAFE( arena, next, &pool->arena_list, struct pool_arena, entry )
     {
-        next = arena->next;
+        list_remove( &arena->entry );
+        HeapFree(GetProcessHeap(), 0, arena);
+    }
+    LIST_FOR_EACH_ENTRY_SAFE( arena, next, &pool->arena_full, struct pool_arena, entry )
+    {
+        list_remove( &arena->entry );
         HeapFree(GetProcessHeap(), 0, arena);
-        arena = next;
     }
-    pool_init(pool, 0);
 }
 
-void* pool_alloc(struct pool* pool, unsigned len)
+void* pool_alloc(struct pool* pool, size_t len)
 {
     struct pool_arena*  arena;
     void*               ret;
+    size_t size;
 
     len = (len + 3) & ~3; /* round up size on DWORD boundary */
-    assert(sizeof(struct pool_arena) + len <= pool->arena_size && len);
 
-    for (arena = pool->first; arena; arena = arena->next)
+    LIST_FOR_EACH_ENTRY( arena, &pool->arena_list, struct pool_arena, entry )
     {
-        if ((char*)arena + pool->arena_size - arena->current >= len)
+        if (arena->end - arena->current >= len)
         {
             ret = arena->current;
             arena->current += len;
+            if (arena->current + 16 >= arena->end)
+            {
+                list_remove( &arena->entry );
+                list_add_tail( &pool->arena_full, &arena->entry );
+            }
             return ret;
         }
     }
 
-    arena = HeapAlloc(GetProcessHeap(), 0, pool->arena_size);
-    if (!arena) {ERR("OOM\n");return NULL;}
+    size = max( pool->arena_size, len + sizeof(struct pool_arena) );
+    arena = HeapAlloc(GetProcessHeap(), 0, size);
+    if (!arena) {ERR("OOM for %u\n", size);return NULL;}
 
-    ret = (char*)arena + sizeof(*arena);
-    arena->next = pool->first;
-    pool->first = arena;
+    ret = arena + 1;
     arena->current = (char*)ret + len;
+    arena->end = (char *)arena + size;
+    if (arena->current + 16 >= arena->end)
+        list_add_tail( &pool->arena_full, &arena->entry );
+    else
+        list_add_head( &pool->arena_list, &arena->entry );
     return ret;
 }