Switch stacks in CALL32_Init().

include/main.h

@@ -17,7 +17,7 @@ extern void MAIN_ParseModeOption( char *arg );
 
 extern BOOL RELAY_Init(void);
 extern int RELAY_ShowDebugmsgRelay(const char *func);
-extern void* CALL32_Init(void);
+extern void CALL32_Init( void *func, void *target, void *stack );
 
 extern BOOL THUNK_Init(void);
 

miscemu/main.c

@@ -158,13 +158,14 @@ int main( int argc, char *argv[] )
     if ( !(pModule = NE_GetPtr( GetModuleHandle16( "KERNEL" ) )) ) return 1;
     if ( !TASK_Create( THREAD_Current(), pModule, 0, 0, FALSE ) ) return 1;
 
-    /* Initialize CALL32 routines */
-    /* This needs to be done just before switching stacks */
-    IF1632_CallLargeStack = (int (*)(int (*func)(), void *arg))CALL32_Init();
-
     /* Switch to initial task */
-    CURRENT_STACK16->frame32->retaddr = (DWORD)MAIN_EmulatorRun;
-    TASK_StartTask( PROCESS_Current()->task );
-    MSG( "main: Should never happen: returned from TASK_StartTask()\n" );
+    PostEvent16( PROCESS_Current()->task );
+    TASK_Reschedule();
+
+    /* Switch stacks and jump to MAIN_EmulatorRun */
+    CALL32_Init( &IF1632_CallLargeStack, MAIN_EmulatorRun,
+                 THREAD_Current()->teb.stack_top );
+
+    MSG( "main: Should never happen: returned from CALL32_Init()\n" );
     return 0;
 }

tools/build.c

@@ -2488,11 +2488,20 @@ static void BuildCallTo32CBClient( FILE *outfile, BOOL isEx )
  *
  * The pointer to the function can be retrieved by calling CALL32_Init,
  * which also takes care of saving the current 32-bit stack pointer.
+ * Furthermore, CALL32_Init switches to a new stack and jumps to the
+ * specified target address.
  *
  * NOTE: The CALL32_LargeStack routine may be recursively entered by the 
  *       same thread, but not concurrently entered by several threads.
  *
- * Stack layout:
+ * Stack layout of CALL32_Init:
+ *
+ * (esp+12)  new stack address
+ * (esp+8)   target address
+ * (esp+4)   pointer to variable to receive CALL32_LargeStack address
+ * (esp)     ret addr
+ *
+ * Stack layout of CALL32_LargeStack:
  *   ...     ...
  * (ebp+12)  arg
  * (ebp+8)   func
@@ -2510,9 +2519,13 @@ static void BuildCallTo32LargeStack( FILE *outfile )
     fprintf( outfile, "\t.globl " PREFIX "CALL32_Init\n" );
     fprintf( outfile, "\t.type " PREFIX "CALL32_Init,@function\n" );
     fprintf( outfile, PREFIX "CALL32_Init:\n" );
-    fprintf( outfile, "\tleal -256(%%esp),%%eax\n" );
-    fprintf( outfile, "\tmovl %%eax,CALL32_Original32_esp\n" );
-    fprintf( outfile, "\tmovl $CALL32_LargeStack,%%eax\n" );
+    fprintf( outfile, "\tmovl %%esp,CALL32_Original32_esp\n" );
+    fprintf( outfile, "\tpopl %%eax\n" );
+    fprintf( outfile, "\tpopl %%eax\n" );
+    fprintf( outfile, "\tmovl $CALL32_LargeStack,(%%eax)\n" );
+    fprintf( outfile, "\tpopl %%eax\n" );
+    fprintf( outfile, "\tpopl %%esp\n" );
+    fprintf( outfile, "\tpushl %%eax\n" );
     fprintf( outfile, "\tret\n" );
 
     /* Function header */