Make the call exception handler function more compatible with NT and

with what Shrinker expects.
This commit is contained in:
Robert Shearman 2005-11-01 09:21:03 +00:00 committed by Alexandre Julliard
parent 3e29148bcf
commit 2a02dd1f05
2 changed files with 37 additions and 24 deletions

View File

@ -114,8 +114,6 @@ static DWORD EXC_UnwindHandler( EXCEPTION_RECORD *rec, EXCEPTION_REGISTRATION_RE
*
* Call an exception handler, setting up an exception frame to catch exceptions
* happening during the handler execution.
* Please do not change the first 4 parameters order in any way - some exceptions handlers
* rely on Base Pointer (EBP) to have a fixed position related to the exception frame
*
* For i386 this function is implemented in assembler in signal_i386.c.
*/

View File

@ -1387,33 +1387,48 @@ __ASM_GLOBAL_FUNC( DbgUserBreakPoint, "int $3; ret");
/**********************************************************************
* EXC_CallHandler (internal)
*
* Some exception handlers depend on EBP to have a fixed position relative to
* the exception frame.
* Shrinker depends on (*1) doing what it does,
* (*2) being the exact instruction it is and (*3) beginning with 0x64
* (i.e. the %fs prefix to the movl instruction). It also depends on the
* function calling the handler having only 5 parameters (*4).
*/
__ASM_GLOBAL_FUNC( EXC_CallHandler,
" pushl %ebp\n"
" movl %esp, %ebp\n"
" subl $12, %esp\n"
" movl 28(%ebp), %eax\n"
" movl 12(%ebp), %edx\n"
" movl %eax, -8(%ebp)\n"
" movl %edx, -4(%ebp)\n"
" leal -12(%ebp), %eax\n"
" .byte 0x64\n"
" movl (0),%ecx\n"
" movl %ecx,(%eax)\n"
" .byte 0x64\n"
" movl %eax,(0)\n"
" movl 20(%ebp), %eax\n"
" pushl %eax\n"
" movl 16(%ebp), %eax\n"
" pushl %eax\n"
" movl 8(%ebp), %eax\n"
" pushl %edx\n"
" pushl %eax\n"
" call *24(%ebp)\n"
" movl -12(%ebp), %edx\n"
" .byte 0x64\n"
" movl %edx,(0)\n"
" movl 28(%ebp), %edx\n" /* ugly hack to pass the 6th param needed because of Shrinker */
" pushl 24(%ebp)\n"
" pushl 20(%ebp)\n"
" pushl 16(%ebp)\n"
" pushl 12(%ebp)\n"
" pushl 8(%ebp)\n"
" call call_exception_handler\n"
" leave\n"
" ret\n"
);
__ASM_GLOBAL_FUNC(call_exception_handler,
" pushl %ebp\n"
" movl %esp, %ebp\n"
" pushl 12(%ebp)\n" /* make any exceptions in this... */
" pushl %edx\n" /* handler be handled by... */
" .byte 0x64\n"
" pushl (0)\n" /* nested_handler (passed in edx). */
" .byte 0x64\n"
" movl %esp,(0)\n" /* push the new exception frame onto the exception stack. */
" pushl 20(%ebp)\n"
" pushl 16(%ebp)\n"
" pushl 12(%ebp)\n"
" pushl 8(%ebp)\n"
" movl 24(%ebp), %ecx\n" /* (*1) */
" call *%ecx\n" /* call handler. (*2) */
" .byte 0x64\n"
" movl (0), %esp\n" /* restore previous... (*3) */
" .byte 0x64\n"
" popl (0)\n" /* exception frame. */
" movl %ebp, %esp\n" /* restore saved stack, in case it was corrupted */
" popl %ebp\n"
" ret $20\n" /* (*4) */
);
#endif /* __i386__ */