bool ksbt_isBacktraceTooLong(const STRUCT_MCONTEXT_L* const machineContext,
int maxLength)
{
const uintptr_t instructionAddress = ksmach_instructionAddress(machineContext);
if(instructionAddress == 0)
{
return 0;
}
KSFrameEntry frame = {0};
const uintptr_t framePtr = ksmach_framePointer(machineContext);
if(framePtr == 0 ||
ksmach_copyMem((void*)framePtr, &frame, sizeof(frame)) != KERN_SUCCESS)
{
return 1;
}
for(int i = 1; i < maxLength; i++)
{
if(frame.previous == 0 ||
ksmach_copyMem(frame.previous, &frame, sizeof(frame)) != KERN_SUCCESS)
{
return false;
}
}
return true;
}
int ksbt_backtraceLength(const STRUCT_MCONTEXT_L* const machineContext)
{
const uintptr_t instructionAddress = ksmach_instructionAddress(machineContext);
if(instructionAddress == 0)
{
return 0;
}
KSFrameEntry frame = {0};
const uintptr_t framePtr = ksmach_framePointer(machineContext);
if(framePtr == 0 ||
ksmach_copyMem((void*)framePtr, &frame, sizeof(frame)) != KERN_SUCCESS)
{
return 1;
}
for(int i = 1; i < kBacktraceGiveUpPoint; i++)
{
if(frame.previous == 0 ||
ksmach_copyMem(frame.previous, &frame, sizeof(frame)) != KERN_SUCCESS)
{
return i;
}
}
return kBacktraceGiveUpPoint;
}
int ksbt_backtraceThreadState(const STRUCT_MCONTEXT_L* const machineContext,
uintptr_t*const backtraceBuffer,
const int skipEntries,
const int maxEntries)
{
const uintptr_t instructionAddress = ksmach_instructionAddress(machineContext);
if(maxEntries == 0)
{
return 0;
}
int startPoint = 0;
if(skipEntries == 0)
{
backtraceBuffer[0] = instructionAddress;
if(maxEntries == 1)
{
return 1;
}
startPoint = 1;
}
KSFrameEntry frame = {0};
const uintptr_t framePtr = ksmach_framePointer(machineContext);
if(framePtr == 0 ||
ksmach_copyMem((void*)framePtr, &frame, sizeof(frame)) != KERN_SUCCESS)
{
return 0;
}
for(int i = 1; i < skipEntries; i++)
{
if(frame.previous == 0 ||
ksmach_copyMem(frame.previous, &frame, sizeof(frame)) != KERN_SUCCESS)
{
return 0;
}
}
int i;
for(i = startPoint; i < maxEntries; i++)
{
backtraceBuffer[i] = DETAG_FRAME_CALLER_ADDRESS(frame.caller);
if(backtraceBuffer[i] == 0 ||
frame.previous == 0 ||
ksmach_copyMem(frame.previous, &frame, sizeof(frame)) != KERN_SUCCESS)
{
break;
}
}
return i;
}
int ksbt_backtraceThreadState(const STRUCT_MCONTEXT_L* const machineContext,
uintptr_t*const backtraceBuffer,
const int skipEntries,
const int maxEntries)
{
if(maxEntries == 0)
{
return 0;
}
int i = 0;
if(skipEntries == 0)
{
const uintptr_t instructionAddress = ksmach_instructionAddress(machineContext);
backtraceBuffer[i] = instructionAddress;
i++;
if(i == maxEntries)
{
return i;
}
}
if(skipEntries <= 1)
{
uintptr_t linkRegister = ksmach_linkRegister(machineContext);
if(linkRegister)
{
backtraceBuffer[i] = linkRegister;
i++;
if (i == maxEntries)
{
return i;
}
}
}
KSFrameEntry frame = {0};
const uintptr_t framePtr = ksmach_framePointer(machineContext);
if(framePtr == 0 ||
ksmach_copyMem((void*)framePtr, &frame, sizeof(frame)) != KERN_SUCCESS)
{
return 0;
}
for(int j = 1; j < skipEntries; j++)
{
if(frame.previous == 0 ||
ksmach_copyMem(frame.previous, &frame, sizeof(frame)) != KERN_SUCCESS)
{
return 0;
}
}
for(; i < maxEntries; i++)
{
backtraceBuffer[i] = frame.return_address;
if(backtraceBuffer[i] == 0 ||
frame.previous == 0 ||
ksmach_copyMem(frame.previous, &frame, sizeof(frame)) != KERN_SUCCESS)
{
break;
}
}
return i;
}
