зеркало из https://github.com/mozilla/gecko-dev.git
64 строки
1.8 KiB
C++
64 строки
1.8 KiB
C++
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
|
|
*
|
|
* The contents of this file are subject to the Netscape Public License
|
|
* Version 1.0 (the "NPL"); you may not use this file except in
|
|
* compliance with the NPL. You may obtain a copy of the NPL at
|
|
* http://www.mozilla.org/NPL/
|
|
*
|
|
* Software distributed under the NPL is distributed on an "AS IS" basis,
|
|
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
|
|
* for the specific language governing rights and limitations under the
|
|
* NPL.
|
|
*
|
|
* The Initial Developer of this code under the NPL is Netscape
|
|
* Communications Corporation. Portions created by Netscape are
|
|
* Copyright (C) 1998 Netscape Communications Corporation. All Rights
|
|
* Reserved.
|
|
*/
|
|
#include <stdio.h>
|
|
#include <signal.h>
|
|
#include <asm/sigcontext.h>
|
|
|
|
int old_instruction;
|
|
|
|
int
|
|
SetBreakPoint(void *pc)
|
|
{
|
|
old_instruction = *((unsigned char *) pc);
|
|
*((unsigned char *) pc) = 0xcc; /* break point opcode */
|
|
#ifdef DEBUG
|
|
fprintf(stderr, "breakpoint at: %x\n", (unsigned int) pc);
|
|
#endif
|
|
/* Need to flush icache here */
|
|
return old_instruction;
|
|
}
|
|
|
|
extern "C" void
|
|
sigtrap_handler(int sig, struct sigcontext_struct context)
|
|
{
|
|
#ifdef DEBUG
|
|
fprintf(stderr, "Handler: Restoring old instruction\n");
|
|
fprintf(stderr, "ip: %x\n", (unsigned int) context.eip);
|
|
#endif
|
|
|
|
/* Learnt this the hard way. eip points to the next instruction */
|
|
(*((unsigned char *) (context.eip -1))) = old_instruction;
|
|
context.eip = context.eip - 1;
|
|
|
|
/* Send a debugger event and do all kinds of things */
|
|
|
|
return;
|
|
}
|
|
|
|
void
|
|
SetupBreakPointHandler()
|
|
{
|
|
struct sigaction sigtrap_action;
|
|
|
|
sigemptyset(&sigtrap_action.sa_mask);
|
|
sigtrap_action.sa_flags = 0;
|
|
sigtrap_action.sa_handler = (__sighandler_t) sigtrap_handler;
|
|
|
|
sigaction(SIGTRAP, &sigtrap_action, NULL);
|
|
}
|