125 lines
4.0 KiB
C++
125 lines
4.0 KiB
C++
/* Ham Sandwich
|
|
* Copyright 2007-2014
|
|
* By the AMX Mod X Development Team
|
|
*
|
|
* Ham Sandwich is free software; you can redistribute it and/or modify it
|
|
* under the terms of the GNU General Public License as published by the
|
|
* Free Software Foundation; either version 2 of the License, or (at
|
|
* your option) any later version.
|
|
*
|
|
* Ham Sandwich is distributed in the hope that it will be useful, but
|
|
* WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with Ham Sandwich; if not, write to the Free Software Foundation,
|
|
* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
*
|
|
* In addition, as a special exception, the author gives permission to
|
|
* link the code of Ham Sandwich with the Half-Life Game Engine ("HL
|
|
* Engine") and Modified Game Libraries ("MODs") developed by Valve,
|
|
* L.L.C ("Valve"). You must obey the GNU General Public License in all
|
|
* respects for all of the code used other than the HL Engine and MODs
|
|
* from Valve. If you modify this file, you may extend this exception
|
|
* to your version of the file, but you are not obligated to do so. If
|
|
* you do not wish to do so, delete this exception statement from your
|
|
* version.
|
|
*/
|
|
#ifndef HOOK_H
|
|
#define HOOK_H
|
|
|
|
#include "forward.h"
|
|
#include "Trampolines.h"
|
|
|
|
#define ALIGN(ar) ((intptr_t)ar & ~(sysconf(_SC_PAGESIZE)-1))
|
|
|
|
// This is just a simple container for data so I only have to add 1 extra
|
|
// parameter to calls that get trampolined
|
|
|
|
class Hook
|
|
{
|
|
public:
|
|
CVector<Forward *> pre; // pre forwards
|
|
CVector<Forward *> post; // post forwards
|
|
void *func; // original function
|
|
void **vtable; // vtable of the original location
|
|
int entry; // vtable entry of the function
|
|
void *target; // target function being called (the hook)
|
|
int exec; // 1 when this hook is in execution
|
|
int del; // 1 if this hook should be destroyed after exec
|
|
void *tramp; // trampoline for this hook
|
|
char *ent; // ent name that's being hooked
|
|
|
|
Hook(void **vtable_, int entry_, void *target_, bool voidcall, bool retbuf, int paramcount, char *name) :
|
|
func(NULL), vtable(vtable_), entry(entry_), target(target_), exec(0), del(0), tramp(NULL)
|
|
{
|
|
// original function is vtable[entry]
|
|
// to not make the compiler whine, cast vtable to int **
|
|
int **ivtable=(int **)vtable;
|
|
func=(void *)ivtable[entry];
|
|
|
|
// now install a trampoline
|
|
// (int thiscall, int voidcall, int paramcount, void *extraptr)
|
|
tramp = CreateGenericTrampoline(true, voidcall, retbuf, paramcount, (void*)this, target);
|
|
|
|
// Insert into vtable
|
|
#if defined(_WIN32)
|
|
DWORD OldFlags;
|
|
VirtualProtect(&ivtable[entry],sizeof(int*),PAGE_READWRITE,&OldFlags);
|
|
#elif defined(__linux__) || defined(__APPLE__)
|
|
void *addr = (void *)ALIGN(&ivtable[entry]);
|
|
mprotect(addr,sysconf(_SC_PAGESIZE),PROT_READ|PROT_WRITE);
|
|
#endif
|
|
ivtable[entry]=(int*)tramp;
|
|
|
|
size_t len=strlen(name);
|
|
ent=new char[len+1];
|
|
|
|
snprintf(ent,len+1,"%s",name);
|
|
};
|
|
|
|
~Hook()
|
|
{
|
|
// Insert the original function back into the vtable
|
|
int **ivtable=(int **)vtable;
|
|
|
|
#if defined(_WIN32)
|
|
DWORD OldFlags;
|
|
VirtualProtect(&ivtable[entry],sizeof(int*),PAGE_READWRITE,&OldFlags);
|
|
#elif defined(__linux__) || defined(__APPLE__)
|
|
void *addr = (void *)ALIGN(&ivtable[entry]);
|
|
mprotect(addr,sysconf(_SC_PAGESIZE),PROT_READ|PROT_WRITE);
|
|
#endif
|
|
|
|
ivtable[entry]=(int *)func;
|
|
#if defined(_WIN32)
|
|
VirtualFree(tramp, 0, MEM_RELEASE);
|
|
#elif defined(__linux__) || defined(__APPLE__)
|
|
free(tramp);
|
|
#endif
|
|
|
|
delete[] ent;
|
|
|
|
CVector<Forward *>::iterator end=pre.end();
|
|
|
|
for (CVector<Forward *>::iterator i=pre.begin();
|
|
i!=end;
|
|
++i)
|
|
{
|
|
delete (*i);
|
|
}
|
|
end=post.end();
|
|
for (CVector<Forward *>::iterator i=post.begin();
|
|
i!=end;
|
|
++i)
|
|
{
|
|
delete (*i);
|
|
}
|
|
pre.clear();
|
|
post.clear();
|
|
}
|
|
};
|
|
|
|
#endif
|