DWORD
PAL_DeleteExecWatchpoint(
HANDLE hThread,
PVOID pvInstruction
)
{
PERF_ENTRY(PAL_DeleteExecWatchpoint);
ENTRY("PAL_DeleteExecWatchpoint (hThread=%p, pvInstruction=%p)\n", hThread, pvInstruction);
DWORD dwError = ERROR_NOT_SUPPORTED;
#if HAVE_PRWATCH_T
CPalThread *pThread = NULL;
CPalThread *pTargetThread = NULL;
IPalObject *pobjThread = NULL;
int fd = -1;
char ctlPath[50];
struct
{
long ctlCode;
prwatch_t prwatch;
} ctlStruct;
pThread = InternalGetCurrentThread();
dwError = InternalGetThreadDataFromHandle(
pThread,
hThread,
0, // THREAD_SET_CONTEXT
&pTargetThread,
&pobjThread
);
if (NO_ERROR != dwError)
{
goto PAL_DeleteExecWatchpointExit;
}
snprintf(ctlPath, sizeof(ctlPath), "/proc/%u/lwp/%u/lwpctl", getpid(), pTargetThread->GetLwpId());
fd = InternalOpen(pThread, ctlPath, O_WRONLY);
if (-1 == fd)
{
ERROR("Failed to open %s\n", ctlPath);
dwError = ERROR_INVALID_ACCESS;
goto PAL_DeleteExecWatchpointExit;
}
ctlStruct.ctlCode = PCWATCH;
ctlStruct.prwatch.pr_vaddr = (uintptr_t) pvInstruction;
ctlStruct.prwatch.pr_size = sizeof(DWORD);
ctlStruct.prwatch.pr_wflags = 0;
if (write(fd, (void*) &ctlStruct, sizeof(ctlStruct)) != sizeof(ctlStruct))
{
ERROR("Failure writing control structure (errno = %u)\n", errno);
dwError = ERROR_INTERNAL_ERROR;
goto PAL_DeleteExecWatchpointExit;
}
dwError = ERROR_SUCCESS;
PAL_DeleteExecWatchpointExit:
if (NULL != pobjThread)
{
pobjThread->ReleaseReference(pThread);
}
if (-1 != fd)
{
close(fd);
}
#endif // HAVE_PRWATCH_T
LOGEXIT("PAL_DeleteExecWatchpoint returns ret:%d\n", dwError);
PERF_EXIT(PAL_DeleteExecWatchpoint);
return dwError;
}
DWORD
PAL_CreateExecWatchpoint(
HANDLE hThread,
PVOID pvInstruction
)
{
PERF_ENTRY(PAL_CreateExecWatchpoint);
ENTRY("PAL_CreateExecWatchpoint (hThread=%p, pvInstruction=%p)\n", hThread, pvInstruction);
DWORD dwError = ERROR_NOT_SUPPORTED;
#if HAVE_PRWATCH_T
CPalThread *pThread = NULL;
CPalThread *pTargetThread = NULL;
IPalObject *pobjThread = NULL;
int fd = -1;
char ctlPath[50];
struct
{
long ctlCode;
prwatch_t prwatch;
} ctlStruct;
//
// We must never set a watchpoint on an instruction that enters a syscall;
// if such a request comes in we succeed it w/o actually creating the
// watchpoint. This mirrors the behavior of setting the single-step flag
// in a thread context when the thread is w/in a system service -- the
// flag is ignored and will not be present when the thread returns
// to user mode.
//
#if defined(_SPARC_)
if (*(DWORD*)pvInstruction == 0x91d02008) // ta 8
{
TRACE("Watchpoint requested on sysenter instruction -- ignoring");
dwError = ERROR_SUCCESS;
goto PAL_CreateExecWatchpointExit;
}
#else
#error Need syscall instruction for this platform
#endif // _SPARC_
pThread = InternalGetCurrentThread();
dwError = InternalGetThreadDataFromHandle(
pThread,
hThread,
0, // THREAD_SET_CONTEXT
&pTargetThread,
&pobjThread
);
if (NO_ERROR != dwError)
{
goto PAL_CreateExecWatchpointExit;
}
snprintf(ctlPath, sizeof(ctlPath), "/proc/%u/lwp/%u/lwpctl", getpid(), pTargetThread->GetLwpId());
fd = InternalOpen(pThread, ctlPath, O_WRONLY);
if (-1 == fd)
{
ERROR("Failed to open %s\n", ctlPath);
dwError = ERROR_INVALID_ACCESS;
goto PAL_CreateExecWatchpointExit;
}
ctlStruct.ctlCode = PCWATCH;
ctlStruct.prwatch.pr_vaddr = (uintptr_t) pvInstruction;
ctlStruct.prwatch.pr_size = sizeof(DWORD);
ctlStruct.prwatch.pr_wflags = WA_EXEC | WA_TRAPAFTER;
if (write(fd, (void*) &ctlStruct, sizeof(ctlStruct)) != sizeof(ctlStruct))
{
ERROR("Failure writing control structure (errno = %u)\n", errno);
dwError = ERROR_INTERNAL_ERROR;
goto PAL_CreateExecWatchpointExit;
}
dwError = ERROR_SUCCESS;
PAL_CreateExecWatchpointExit:
if (NULL != pobjThread)
{
pobjThread->ReleaseReference(pThread);
}
if (-1 != fd)
{
close(fd);
}
#endif // HAVE_PRWATCH_T
LOGEXIT("PAL_CreateExecWatchpoint returns ret:%d\n", dwError);
PERF_EXIT(PAL_CreateExecWatchpoint);
return dwError;
}
