While playing around with handling interrupts from 32 bit code,
I noticed that Wine failed to catch interrupts if instruction
pointer was over 0xffff. Little looking around made it clear
that every MapSL call in memory/instr.c used MAKESEGPTR to
convert segment-address pairs into SEGPTRs. However, MAKESEGPTR
converts its arguments into WORDs which means that 32-bit
addresses are truncated. This means that emulating privileged
instructions in 32-bit code does not work properly.
All three fixes should work properly both with 16-bit addresses and
with 32-bit addresses. It is likely that at least files msdos/*.c are
full of similar bugs which makes supporting 32-bit DPMI mode even more
difficult.
Changelog:
When using MapSL, 32-bit addresses are no longer truncated into 16-bit addresses.
Index: memory/instr.c
===================================================================
RCS file: /home/wine/wine/memory/instr.c,v
retrieving revision 1.14
diff -u -r1.14 instr.c
--- memory/instr.c 10 Mar 2002 00:18:34 -0000 1.14
+++ memory/instr.c 11 May 2002 14:36:14 -0000
@@ -44,7 +44,7 @@
if (ISV86(context)) return PTR_REAL_TO_LIN( seg, off );
if (IS_SELECTOR_SYSTEM(seg)) return (void *)off;
if (!long_addr) off = LOWORD(off);
- return MapSL( MAKESEGPTR( seg, off ) );
+ return MapSL( MAKESEGPTR( seg, 0 ) ) + off;
}
inline static void *get_stack( CONTEXT86 *context )
@@ -54,7 +54,7 @@
if (IS_SELECTOR_SYSTEM(context->SegSs))
return (void *)context->Esp;
if (IS_SELECTOR_32BIT(context->SegSs))
- return MapSL( MAKESEGPTR( context->SegSs, context->Esp ) );
+ return MapSL( MAKESEGPTR( context->SegSs, 0 ) ) + context->Esp;
return MapSL( MAKESEGPTR( context->SegSs, LOWORD(context->Esp) ) );
}
@@ -249,7 +249,7 @@
if (IS_SELECTOR_SYSTEM(seg)) return (BYTE *)(base + (index << ss));
if (((seg & 7) != 7) || IS_SELECTOR_FREE(seg)) return NULL;
if (wine_ldt_copy.limit[seg >> 3] < (base + (index << ss))) return NULL;
- return MapSL( MAKESEGPTR( seg, (base + (index << ss))) );
+ return MapSL( MAKESEGPTR( seg, 0 ) ) + base + (index << ss);
#undef GET_VAL
}
--
Jukka Heinonen <http://www.iki.fi/jhei/>
