From 63806aad9f348768654ac78751c7d0bc7aa77464 Mon Sep 17 00:00:00 2001
From: Alexei Podtelezhnikov <apodtele@gmail.com>
Date: Wed, 8 Sep 2021 10:54:44 -0400
Subject: [PATCH] Fortify memory debugging.

These changes are neccessary to properly recover `memory->user` that
holds the Windows heap handle now.

* src/base/ftdbgmem.c (ft_mem_debug_init): Handle all table allocations,
initializations, and sizing instead of...
(ft_mem_table_new): ... this function removed.
(ft_mem_debug_done): Better check for the active debugger and free the
debugger table here instead of...
(ft_mem_table_destroy): ... here.
---
 src/base/ftdbgmem.c | 84 +++++++++++++++------------------------------
 1 file changed, 28 insertions(+), 56 deletions(-)

diff --git a/src/base/ftdbgmem.c b/src/base/ftdbgmem.c
index 8425ca702..5f1d20eec 100644
--- a/src/base/ftdbgmem.c
+++ b/src/base/ftdbgmem.c
@@ -302,46 +302,6 @@
   }
 
 
-  static FT_MemTable
-  ft_mem_table_new( FT_Memory  memory )
-  {
-    FT_MemTable  table;
-
-
-    table = (FT_MemTable)memory->alloc( memory, sizeof ( *table ) );
-    if ( !table )
-      goto Exit;
-
-    FT_ZERO( table );
-
-    table->size  = FT_MEM_SIZE_MIN;
-    table->nodes = 0;
-
-    table->memory = memory;
-
-    table->memory_user = memory->user;
-
-    table->alloc   = memory->alloc;
-    table->realloc = memory->realloc;
-    table->free    = memory->free;
-
-    table->buckets = (FT_MemNode *)
-                       memory->alloc(
-                         memory,
-                         table->size * (FT_Long)sizeof ( FT_MemNode ) );
-    if ( table->buckets )
-      FT_ARRAY_ZERO( table->buckets, table->size );
-    else
-    {
-      memory->free( memory, table );
-      table = NULL;
-    }
-
-  Exit:
-    return table;
-  }
-
-
   static void
   ft_mem_table_destroy( FT_MemTable  table )
   {
@@ -413,8 +373,6 @@
     printf( "FreeType: maximum memory footprint = %ld\n",
             table->alloc_max );
 
-    ft_mem_table_free( table, table );
-
     if ( leak_count > 0 )
       ft_mem_debug_panic(
         "FreeType: %ld bytes of memory leaked in %ld blocks\n",
@@ -821,17 +779,30 @@
   }
 
 
-  extern FT_Int
+  extern void
   ft_mem_debug_init( FT_Memory  memory )
   {
     FT_MemTable  table;
-    FT_Int       result = 0;
 
 
-    if ( ft_getenv( "FT2_DEBUG_MEMORY" ) )
+    if ( !ft_getenv( "FT2_DEBUG_MEMORY" ) )
+      return;
+
+    table = (FT_MemTable)memory->alloc( memory, sizeof ( *table ) );
+
+    if ( table )
     {
-      table = ft_mem_table_new( memory );
-      if ( table )
+      FT_ZERO( table );
+
+      table->memory      = memory;
+      table->memory_user = memory->user;
+      table->alloc       = memory->alloc;
+      table->realloc     = memory->realloc;
+      table->free        = memory->free;
+
+      ft_mem_table_resize( table );
+
+      if ( table->size )
       {
         const char*  p;
 
@@ -876,28 +847,29 @@
           if ( keep_alive > 0 )
             table->keep_alive = 1;
         }
-
-        result = 1;
       }
+      else
+        memory->free( memory, table );
     }
-    return result;
   }
 
 
   extern void
   ft_mem_debug_done( FT_Memory  memory )
   {
-    FT_MemTable  table = (FT_MemTable)memory->user;
-
-
-    if ( table )
+    if ( memory->free == ft_mem_debug_free )
     {
+      FT_MemTable  table = (FT_MemTable)memory->user;
+
+
+      ft_mem_table_destroy( table );
+
       memory->free    = table->free;
       memory->realloc = table->realloc;
       memory->alloc   = table->alloc;
+      memory->user    = table->memory_user;
 
-      ft_mem_table_destroy( table );
-      memory->user = NULL;
+      memory->free( memory, table );
     }
   }