Setup exception frame around 16-bit calls to unwind stack properly.

dlls/kernel/thunk.c

@@ -27,6 +27,7 @@
 #include "windef.h"
 #include "winbase.h"
 #include "winerror.h"
+#include "ntddk.h"
 #include "wine/winbase16.h"
 
 #include "wine/debug.h"
@@ -2091,6 +2092,7 @@ void WINAPI Throw16( LPCATCHBUF lpbuf, INT16 retval, CONTEXT86 *context )
         }
         frame32 = ((STACK16FRAME *)MapSL(frame32->frame16))->frame32;
     }
+    RtlUnwind( &pFrame->frame32->frame, NULL, NULL, 0 );
 
     context->Eip = lpbuf[0];
     context->SegCs  = lpbuf[1];

dlls/ntdll/exception.c

@@ -403,10 +403,29 @@ DWORD __wine_exception_handler( EXCEPTION_RECORD *record, EXCEPTION_FRAME *frame
 DWORD __wine_finally_handler( EXCEPTION_RECORD *record, EXCEPTION_FRAME *frame,
                               CONTEXT *context, LPVOID pdispatcher )
 {
+    if (record->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND))
+    {
         __WINE_FRAME *wine_frame = (__WINE_FRAME *)frame;
-
-    if (!(record->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND)))
-        return ExceptionContinueSearch;
         wine_frame->u.finally_func( FALSE );
+    }
+    return ExceptionContinueSearch;
+}
+
+
+/*************************************************************
+ *            __wine_callto16_handler
+ *
+ * Handler for exceptions occuring in 16-bit code.
+ */
+DWORD __wine_callto16_handler( EXCEPTION_RECORD *record, EXCEPTION_FRAME *frame,
+                               CONTEXT *context, LPVOID pdispatcher )
+{
+    if (record->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND))
+    {
+        /* unwinding: restore the stack pointer in the TEB, and leave the Win16 mutex */
+        STACK32FRAME *frame32 = (STACK32FRAME *)((char *)frame - offsetof(STACK32FRAME,frame));
+        NtCurrentTeb()->cur_stack = frame32->frame16;
+        _LeaveWin16Lock();
+    }
     return ExceptionContinueSearch;
 }

include/stackframe.h

@@ -32,18 +32,19 @@
   /* 32-bit stack layout after CallTo16() */
 typedef struct _STACK32FRAME
 {
-    SEGPTR  frame16;        /* 00 16-bit frame from last CallFrom16() */
-    DWORD   restore_addr;   /* 04 return address for restoring code selector */
-    DWORD   codeselector;   /* 08 code selector to restore */
-    DWORD   edi;            /* 0c saved registers */
-    DWORD   esi;            /* 10 */
-    DWORD   edx;            /* 14 */
-    DWORD   ecx;            /* 18 */
-    DWORD   ebx;            /* 1c */
-    DWORD   ebp;            /* 20 saved 32-bit frame pointer */
-    DWORD   retaddr;        /* 24 return address */
-    DWORD   target;         /* 28 target address / CONTEXT86 pointer */
-    DWORD   nb_args;        /* 2c number of 16-bit argument bytes */
+    DWORD   restore_addr;   /* 00 return address for restoring code selector */
+    DWORD   codeselector;   /* 04 code selector to restore */
+    EXCEPTION_FRAME frame;  /* 08 Exception frame */
+    SEGPTR  frame16;        /* 10 16-bit frame from last CallFrom16() */
+    DWORD   edi;            /* 14 saved registers */
+    DWORD   esi;            /* 18 */
+    DWORD   edx;            /* 1c */
+    DWORD   ecx;            /* 20 */
+    DWORD   ebx;            /* 24 */
+    DWORD   ebp;            /* 28 saved 32-bit frame pointer */
+    DWORD   retaddr;        /* 2c return address */
+    DWORD   target;         /* 30 target address / CONTEXT86 pointer */
+    DWORD   nb_args;        /* 34 number of 16-bit argument bytes */
 } STACK32FRAME;
 
   /* 16-bit stack layout after CallFrom16() */

tools/winebuild/relay.c

@@ -501,12 +501,6 @@ static void BuildCallTo16Core( FILE *outfile, int short_ret, int reg_func )
         fprintf( outfile, "\taddl $_GLOBAL_OFFSET_TABLE_+[.-.Lwine_call_to_16_%s.getgot1], %%ebx\n", name );
     }
 
-    /* Enter Win16 Mutex */
-    if ( UsePIC )
-        fprintf( outfile, "\tcall " __ASM_NAME("_EnterWin16Lock@PLT") "\n" );
-    else
-        fprintf( outfile, "\tcall " __ASM_NAME("_EnterWin16Lock") "\n" );
-
     /* Print debugging info */
     if (debugging)
     {
@@ -523,6 +517,21 @@ static void BuildCallTo16Core( FILE *outfile, int short_ret, int reg_func )
         fprintf( outfile, "\taddl $12, %%esp\n" );
     }
 
+    /* Enter Win16 Mutex */
+    if ( UsePIC )
+        fprintf( outfile, "\tcall " __ASM_NAME("_EnterWin16Lock@PLT") "\n" );
+    else
+        fprintf( outfile, "\tcall " __ASM_NAME("_EnterWin16Lock") "\n" );
+
+    /* Setup exception frame */
+    fprintf( outfile, "\t.byte 0x64\n\tpushl (%d)\n", STACKOFFSET );
+    if (UsePIC)
+        fprintf( outfile, "\tpushl " __ASM_NAME("__wine_callto16_handler@GOT") "(%%ebx)\n" );
+    else
+        fprintf( outfile, "\tpushl $" __ASM_NAME("__wine_callto16_handler") "\n" );
+    fprintf( outfile, "\t.byte 0x64\n\tpushl (%d)\n", STRUCTOFFSET(TEB,except) );
+    fprintf( outfile, "\t.byte 0x64\n\tmovl %%esp,(%d)\n", STRUCTOFFSET(TEB,except) );
+
     /* Get return address */
     if ( UsePIC )
     {
@@ -534,7 +543,12 @@ static void BuildCallTo16Core( FILE *outfile, int short_ret, int reg_func )
 
     /* Call the actual CallTo16 routine (simulate a lcall) */
     fprintf( outfile, "\tpushl %%cs\n" );
-    fprintf( outfile, "\tcall .Lwine_call_to_16_%s\n", name );
+    fprintf( outfile, "\tcall .Lwine_call_to_16_%s\n", reg_func ? name : "long" );
+
+    /* Remove exception frame */
+    fprintf( outfile, "\t.byte 0x64\n\tpopl (%d)\n", STRUCTOFFSET(TEB,except) );
+    fprintf( outfile, "\taddl $4, %%esp\n" );
+    fprintf( outfile, "\t.byte 0x64\n\tpopl (%d)\n", STACKOFFSET );
 
     if ( !reg_func )
     {
@@ -563,7 +577,9 @@ static void BuildCallTo16Core( FILE *outfile, int short_ret, int reg_func )
          *        at the cost of a somewhat less efficient return path.]
          */
 
-        fprintf( outfile, "\tmovl %d(%%esp), %%edi\n", STACK32OFFSET(target)-12 );
+        fprintf( outfile, "\tmovl %d(%%esp), %%edi\n", STACK32OFFSET(target) - STACK32OFFSET(edi));
+                /* everything above edi has been popped already */
+
         fprintf( outfile, "\tmovl %%eax, %d(%%edi)\n", CONTEXTOFFSET(Eax) );
         fprintf( outfile, "\tmovl %%ebx, %d(%%edi)\n", CONTEXTOFFSET(Ebx) );
         fprintf( outfile, "\tmovl %%ecx, %d(%%edi)\n", CONTEXTOFFSET(Ecx) );
@@ -584,6 +600,12 @@ static void BuildCallTo16Core( FILE *outfile, int short_ret, int reg_func )
         fprintf( outfile, "\taddl $_GLOBAL_OFFSET_TABLE_+[.-.Lwine_call_to_16_%s.getgot2], %%ebx\n", name );
     }
 
+    /* Leave Win16 Mutex */
+    if ( UsePIC )
+        fprintf( outfile, "\tcall " __ASM_NAME("_LeaveWin16Lock@PLT") "\n" );
+    else
+        fprintf( outfile, "\tcall " __ASM_NAME("_LeaveWin16Lock") "\n" );
+
     /* Print debugging info */
     if (debugging)
     {
@@ -597,12 +619,6 @@ static void BuildCallTo16Core( FILE *outfile, int short_ret, int reg_func )
         fprintf( outfile, "\taddl $4, %%esp\n" );
     }
 
-    /* Leave Win16 Mutex */
-    if ( UsePIC )
-        fprintf( outfile, "\tcall " __ASM_NAME("_LeaveWin16Lock@PLT") "\n" );
-    else
-        fprintf( outfile, "\tcall " __ASM_NAME("_LeaveWin16Lock") "\n" );
-
     /* Get return value */
     fprintf( outfile, "\tpopl %%eax\n" );
 
@@ -620,13 +636,12 @@ static void BuildCallTo16Core( FILE *outfile, int short_ret, int reg_func )
 
     /* Start of the actual CallTo16 routine */
 
-    fprintf( outfile, ".Lwine_call_to_16_%s:\n", name );
+    if (!reg_func && short_ret) return;  /* call_to_16_word uses call_to_16_long backend routine */
 
-    /* Complete STACK32FRAME */
-    fprintf( outfile, "\t.byte 0x64\n\tpushl (%d)\n", STACKOFFSET );
-    fprintf( outfile, "\tmovl %%esp,%%edx\n" );
+    fprintf( outfile, ".Lwine_call_to_16_%s:\n", name );
 
     /* Switch to the 16-bit stack */
+    fprintf( outfile, "\tmovl %%esp,%%edx\n" );
 #ifdef __svr4__
     fprintf( outfile,"\tdata16\n");
 #endif
@@ -739,7 +754,6 @@ static void BuildRet16Func( FILE *outfile )
 #endif
     fprintf( outfile, "\tmovw %%di,%%ss\n" );
     fprintf( outfile, "\t.byte 0x64\n\tmovl (%d),%%esp\n", STACKOFFSET );
-    fprintf( outfile, "\t.byte 0x64\n\tpopl (%d)\n", STACKOFFSET );
 
     /* Return to caller */