From f87cc876be9b450d3491a174b8c673d918ec5daf Mon Sep 17 00:00:00 2001
From: Pali Rohár <pali.rohar@gmail.com>
Date: Fri, 22 Mar 2024 01:53:18 +0100
Subject: Replace CRT's malloc() and free() by WinAPI's LocalAlloc() and
 LocalFree() in release mode

In debug mode is still used malloc() and free() for as part of memory leak
testing done by _CRTDBG_MAP_ALLOC and _CrtDumpMemoryLeaks() in test.c.

This change allows to wrap CRT's malloc() via dlsym's RTLD_NEXT.

See #112
---
 src/dlfcn.c | 29 +++++++++++++++++++++++------
 1 file changed, 23 insertions(+), 6 deletions(-)

(limited to 'src')

diff --git a/src/dlfcn.c b/src/dlfcn.c
index d52d736..be66cac 100644
--- a/src/dlfcn.c
+++ b/src/dlfcn.c
@@ -30,7 +30,6 @@
 #include <crtdbg.h>
 #endif
 #include <windows.h>
-#include <stdlib.h> /* malloc() and free() */
 #include <string.h> /* strlen() and memcpy() */
 
 /* Older versions do not have this type */
@@ -105,6 +104,24 @@ __declspec( naked ) static void *_ReturnAddress( void ) { __asm mov eax, [ebp+4]
 #define DLFCN_NOINLINE
 #endif
 
+static void *MyAlloc( size_t size )
+{
+#ifdef _DEBUG
+    return malloc( size );
+#else
+    return LocalAlloc( LPTR, size );
+#endif
+}
+
+static void MyFree( void *ptr )
+{
+#ifdef _DEBUG
+    free( ptr );
+#else
+    LocalFree( ptr );
+#endif
+}
+
 /* Note:
  * MSDN says these functions are not thread-safe. We make no efforts to have
  * any kind of thread safety.
@@ -149,7 +166,7 @@ static BOOL local_add( HMODULE hModule )
 
     for( pobject = &first_object; pobject->next; pobject = pobject->next );
 
-    nobject = (local_object *) malloc( sizeof( local_object ) );
+    nobject = (local_object *) MyAlloc( sizeof( local_object ) );
 
     if( !nobject )
         return FALSE;
@@ -179,7 +196,7 @@ static void local_rem( HMODULE hModule )
     if( pobject->previous )
         pobject->previous->next = pobject->next;
 
-    free( pobject );
+    MyFree( pobject );
 }
 
 /* POSIX says dlerror( ) doesn't have to be thread-safe, so we use one
@@ -568,7 +585,7 @@ void *dlsym( void *handle, const char *name )
          */
         if( MyEnumProcessModules( hCurrentProc, NULL, 0, &dwSize ) != 0 )
         {
-            modules = (HMODULE *) malloc( dwSize );
+            modules = (HMODULE *) MyAlloc( dwSize );
             if( modules )
             {
                 if( MyEnumProcessModules( hCurrentProc, modules, dwSize, &cbNeeded ) != 0 && dwSize == cbNeeded )
@@ -587,13 +604,13 @@ void *dlsym( void *handle, const char *name )
                         symbol = GetProcAddress( modules[i], name );
                         if( symbol != NULL )
                         {
-                            free( modules );
+                            MyFree( modules );
                             goto end;
                         }
                     }
 
                 }
-                free( modules );
+                MyFree( modules );
             }
             else
             {
-- 
cgit v1.2.3-55-g6feb