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"""
Miscellaneous (Intel) platform-specific commands.
"""

from xnu import *
import xnudefines

from scheduler import *

@lldb_command('showlogstream')
def showLogStream(cmd_args=None):
    """
    Dump the state of the kernel log stream
    """
    mbp = kern.globals.oslog_streambufp
    print "streaming buffer space avail: {0:>#x} of {1:>#x} bytes\n".format(kern.globals.oslog_stream_buf_bytesavail, kern.globals.oslog_stream_buf_size)
    print " read head: offset {0:>#x}\nwrite head: offset {1:>#x}\n".format(mbp.msg_bufr, mbp.msg_bufx)
    count = 0
    print "  id  timestamp   offset size off+size type metadata"
    for entry in IterateSTAILQ_HEAD(kern.globals.oslog_stream_buf_head, "buf_entries"):
        next_start = entry.offset + entry.size
        if (next_start > 0x1000):
            next_start = next_start - 0x1000
        print "{0:>4d}: {1:<d}  {2:>5x} {3:>4d} {4:>5x} {5:<d}    {6:<d}".format(count, entry.timestamp, entry.offset, entry.size, next_start, entry.type, entry.metadata)
        count = count + 1
    print "found {} entries".format(count)

    count = 0
    for entry in IterateSTAILQ_HEAD(kern.globals.oslog_stream_free_head, "buf_entries"):
        count = count + 1
    print "free list: {} entries".format(count)

    count = 0
    for outer in IterateSTAILQ_HEAD(kern.globals.oslog_stream_buf_head, "buf_entries"):
        for inner in IterateSTAILQ_HEAD(kern.globals.oslog_stream_buf_head, "buf_entries"):
            if ((outer.offset > inner.offset) and
                (outer.offset < inner.offset + inner.size)):
                print "error: overlapping entries: {:>3x} <--> {:>3x}".format(outer.offset, inner.offset)
        count = count + 1

@lldb_command('showmcastate')
def showMCAstate(cmd_args=None):
    """
    Print machine-check register state after MC exception.
    """
    if kern.arch != 'x86_64':
        print "Not available for current architecture."
        return

    present = ["not present", "present"]
    print 'MCA {:s}, control MSR {:s}, threshold status {:s}'.format(
    present[int(kern.globals.mca_MCA_present)],
    present[int(kern.globals.mca_control_MSR_present)],
    present[int(kern.globals.mca_threshold_status_present)])
    print '{:d} error banks, family code {:#0x}, machine-check dump state: {:d}'.format(
        kern.globals.mca_error_bank_count,
        kern.globals.mca_dump_state,
        kern.globals.mca_family)
    cpu = 0
    while kern.globals.cpu_data_ptr[cpu]:
        cd = kern.globals.cpu_data_ptr[cpu]
        mc = cd.cpu_mca_state
        if mc:
            print 'CPU {:d}: mca_mcg_ctl: {:#018x} mca_mcg_status {:#018x}'.format(cpu, mc.mca_mcg_ctl, mc.mca_mcg_status.u64)
            hdr = '{:<4s} {:<18s} {:<18s} {:<18s} {:<18s}'
            val = '{:>3d}: {:#018x} {:#018x} {:#018x} {:#018x}'
            print hdr.format('bank',
                    'mca_mci_ctl',
                    'mca_mci_status',
                    'mca_mci_addr',
                    'mca_mci_misc')
            for i in range(int(kern.globals.mca_error_bank_count)):
                bank = mc.mca_error_bank[i]
                print val.format(i,
                    bank.mca_mci_ctl,
                    bank.mca_mci_status.u64,
                    bank.mca_mci_addr,     
                    bank.mca_mci_misc)     
        print 'register state:'
        reg = cd.cpu_desc_index.cdi_ktss.ist1 - sizeof('x86_saved_state_t')
        print lldb_run_command('p/x *(x86_saved_state_t *) ' + hex(reg))
        cpu = cpu + 1

def dumpTimerList(mpqueue):
    """
    Utility function to dump the timer entries in list (anchor).
    anchor is a struct mpqueue_head.
    """

    if mpqueue.count == 0:
        print '(empty)'
        return

    thdr = ' {:<24s}{:<17s}{:<16s} {:<14s} {:<18s} count: {:d} '
    tval = ' {:#018x}: {:16d} {:16d} {:s}{:3d}.{:09d}  ({:#018x})({:#018x}, {:#018x}) ({:s}) {:s}'

    print thdr.format('Entry', 'Deadline', 'soft_deadline', 'Secs To Go', '(*func)(param0, param1)', mpqueue.count)

    for timer_call in ParanoidIterateLinkageChain(mpqueue.head, 'struct timer_call *', 'tc_qlink'):
        recent_timestamp = GetRecentTimestamp()
        if (recent_timestamp < timer_call.tc_pqlink.deadline):
            delta_sign = ' '
            timer_fire = timer_call.tc_pqlink.deadline - recent_timestamp
        else:
            delta_sign = '-'
            timer_fire = recent_timestamp - timer_call.tc_pqlink.deadline

        func_name = kern.Symbolicate(timer_call.tc_func)

        extra_string = ""

        strip_func = kern.StripKernelPAC(unsigned(timer_call.tc_func))

        func_syms = kern.SymbolicateFromAddress(strip_func)
        # returns an array of SBSymbol

        if func_syms and func_syms[0] :
            func_sym = func_syms[0]
            func_name = func_sym.GetName()
            try :

                if "thread_call_delayed_timer" in func_name :
                    group = Cast(timer_call.tc_param0, 'struct thread_call_group *')
                    flavor = Cast(timer_call.tc_param1, 'thread_call_flavor_t')

                    # There's got to be a better way to stringify the enum
                    flavorname = str(flavor).partition(" = ")[2]

                    extra_string += "{:s} {:s}".format(group.tcg_name, flavorname)

                if "thread_timer_expire" in func_name :
                    thread = Cast(timer_call.tc_param0, 'thread_t')

                    tid = thread.thread_id
                    name = GetThreadName(thread)
                    pid = GetProcPIDForTask(thread.task)
                    procname = GetProcNameForTask(thread.task)

                    extra_string += "thread: 0x{:x} {:s} task:{:s}[{:d}]".format(
                            tid, name, procname, pid)
            except:
                print "exception generating extra_string for call: {:#018x}".format(timer_call)
                if dumpTimerList.enable_debug :
                    raise

        tval = ' {:#018x}: {:16d} {:16d} {:s}{:3d}.{:09d}  ({:#018x})({:#018x},{:#018x}) ({:s}) {:s}'
        print tval.format(timer_call,
            timer_call.tc_pqlink.deadline,
            timer_call.tc_soft_deadline,
            delta_sign,
            timer_fire/1000000000,
            timer_fire%1000000000,
            timer_call.tc_func,
            timer_call.tc_param0,
            timer_call.tc_param1,
            func_name, extra_string)

dumpTimerList.enable_debug = False

def GetCpuDataForCpuID(cpu_id):
    """
    Find struct cpu_data for a CPU
    ARM is complicated
    """
    if kern.arch == 'x86_64':
        cpu_data = kern.globals.cpu_data_ptr[cpu_id]
        return cpu_data
    elif kern.arch.startswith('arm'):
        data_entries_addr = kern.GetLoadAddressForSymbol('CpuDataEntries')
        data_entries = kern.GetValueFromAddress(data_entries_addr, 'cpu_data_entry_t *')
        data_entry = data_entries[cpu_id];
        cpu_data_addr = data_entry.cpu_data_vaddr
        return Cast(cpu_data_addr, 'cpu_data_t*')

@lldb_command('longtermtimers')
def longtermTimers(cmd_args=None):
    """
    Print details of long-term timers and stats.
    """

    lt = kern.globals.timer_longterm
    ltt = lt.threshold
    EndofAllTime = long(-1)
    if long(ltt.interval) == EndofAllTime:
        print "Longterm timers disabled"
        return

    if lt.escalates > 0:
        ratio = lt.enqueues / lt.escalates
    else:
        ratio = lt.enqueues
    print     'Longterm timer object: {:#018x}'.format(addressof(lt))
    print     ' queue count         : {:d}'    .format(lt.queue.count)
    print     ' number of enqueues  : {:d}'    .format(lt.enqueues)
    print     ' number of dequeues  : {:d}'    .format(lt.dequeues)
    print     ' number of escalates : {:d}'    .format(lt.escalates)
    print     ' enqueues/escalates  : {:d}'    .format(ratio)
    print     ' threshold.interval  : {:d}'    .format(ltt.interval)
    print     ' threshold.margin    : {:d}'    .format(ltt.margin)
    print     ' scan_time           : {:#018x} ({:d})'.format(lt.scan_time, lt.scan_time)
    if long(ltt.preempted) == EndofAllTime:
        print ' threshold.preempted : None'
    else:
        print ' threshold.preempted : {:#018x} ({:d})'.format(ltt.preempted, ltt.preempted)
    if long(ltt.deadline) == EndofAllTime:
        print ' threshold.deadline  : None'
    else:
        print ' threshold.deadline  : {:#018x} ({:d})'.format(ltt.deadline, ltt.deadline)
        print ' threshold.call      : {:#018x}'.format(ltt.call)
        print ' actual deadline set : {:#018x} ({:d})'.format(ltt.deadline_set, ltt.deadline_set)
    print     ' threshold.scans     : {:d}'    .format(ltt.scans)
    print     ' threshold.preempts  : {:d}'    .format(ltt.preempts)
    print     ' threshold.latency   : {:d}'    .format(ltt.latency)
    print     '               - min : {:d}'    .format(ltt.latency_min)
    print     '               - max : {:d}'    .format(ltt.latency_max)
    dumpTimerList(lt.queue)


@lldb_command('processortimers')
def processorTimers(cmd_args=None):
    """
    Print details of processor timers, noting anything suspicious
    Also include long-term timer details
    """
    hdr = '{:15s}{:<18s} {:<18s} {:<18s} {:<18s}'
    print hdr.format('Processor #', 'Processor pointer', 'Last dispatch', 'Next deadline', 'Difference')
    print "=" * 82
    p = kern.globals.processor_list
    EndOfAllTime = long(-1)
    while p:
        cpu = p.cpu_id
        cpu_data = GetCpuDataForCpuID(cpu)
        rt_timer = cpu_data.rtclock_timer
        diff = long(rt_timer.deadline) - long(p.last_dispatch)
        valid_deadline = long(rt_timer.deadline) != EndOfAllTime
        tmr = 'Processor {:<3d}: {:#018x} {:#018x} {:18s} {:18s} {:s}'
        print tmr.format(cpu,
            p,
            p.last_dispatch,
            "{:#018x}".format(rt_timer.deadline) if valid_deadline else "None",
            "{:#018x}".format(diff) if valid_deadline else "N/A",
            ['(PAST DEADLINE)', '(ok)'][int(diff > 0)] if valid_deadline else "")
        if valid_deadline:
            if kern.arch == 'x86_64':
                print 'Next deadline set at: {:#018x}. Timer call list:'.format(rt_timer.when_set)
            dumpTimerList(rt_timer.queue)
        p = p.processor_list
    print "-" * 82
    longtermTimers()
    ShowRunningTimers()


@lldb_command('showtimerwakeupstats')
def showTimerWakeupStats(cmd_args=None):
    """
    Displays interrupt and platform idle wakeup frequencies
    associated with each thread, timer time-to-deadline frequencies, and
    CPU time with user/system break down where applicable, with thread tags.
    """
    for task in kern.tasks:
        proc = Cast(task.bsd_info, 'proc_t')
        print dereference(task)
        print '{:d}({:s}), terminated thread timer wakeups: {:d} {:d} 2ms: {:d} 5ms: {:d} UT: {:d} ST: {:d}'.format(
            proc.p_pid,
            GetProcName(proc),
# Commented-out references below to be addressed by rdar://13009660.
            0, #task.task_interrupt_wakeups,
            0, #task.task_platform_idle_wakeups,
            task.task_timer_wakeups_bin_1,
            task.task_timer_wakeups_bin_2,
            task.total_user_time,
            task.total_system_time)
        tot_wakes = 0 #task.task_interrupt_wakeups
        tot_platform_wakes = 0 #task.task_platform_idle_wakeups
        for thread in IterateQueue(task.threads, 'thread_t', 'task_threads'):
##        if thread.thread_interrupt_wakeups == 0:
##              continue
            print '\tThread ID 0x{:x}, Tag 0x{:x}, timer wakeups: {:d} {:d} {:d} {:d} <2ms: {:d}, <5ms: {:d} UT: {:d} ST: {:d}'.format(
                thread.thread_id,
                thread.thread_tag,
                0, #thread.thread_interrupt_wakeups,
                0, #thread.thread_platform_idle_wakeups,
                0, #thread.thread_callout_interrupt_wakeups,
                0, #thread.thread_callout_platform_idle_wakeups,
                0,0,0,0,
                thread.thread_timer_wakeups_bin_1,
                thread.thread_timer_wakeups_bin_2,
                thread.user_timer.all_bits,
                thread.system_timer.all_bits)
            tot_wakes += 0 #thread.thread_interrupt_wakeups
            tot_platform_wakes += 0 #thread.thread_platform_idle_wakeups
        print 'Task total wakeups: {:d} {:d}'.format(
            tot_wakes, tot_platform_wakes)

@lldb_command('showrunningtimers')
def ShowRunningTimers(cmd_args=None):
    """
    Print the state of all running timers.
    
    Usage: showrunningtimers
    """
    pset = addressof(kern.globals.pset0)
    processor_array = kern.globals.processor_array

    i = 0
    while processor_array[i] != 0:
        processor = processor_array[i]
        print('{}: {}'.format(
                i, 'on' if processor.running_timers_active else 'off'))
        print('\tquantum: {}'.format(
                unsigned(processor.running_timers[0].tc_pqlink.deadline)))
        print('\tkperf: {}'.format(
                unsigned(processor.running_timers[1].tc_pqlink.deadline)))
        i += 1

def DoReadMsr64(msr_address, lcpu):
    """ Read a 64-bit MSR from the specified CPU
        Params:
            msr_address: int - MSR index to read from
            lcpu: int - CPU identifier
        Returns:
            64-bit value read from the MSR
    """
    result = 0xbad10ad

    if "kdp" != GetConnectionProtocol():
        print "Target is not connected over kdp. Cannot read MSR."
        return result

    input_address = unsigned(addressof(kern.globals.manual_pkt.input))
    len_address = unsigned(addressof(kern.globals.manual_pkt.len))
    data_address = unsigned(addressof(kern.globals.manual_pkt.data))
    if not WriteInt32ToMemoryAddress(0, input_address):
        print "DoReadMsr64() failed to write 0 to input_address"
        return result
    
    kdp_pkt_size = GetType('kdp_readmsr64_req_t').GetByteSize()
    if not WriteInt32ToMemoryAddress(kdp_pkt_size, len_address):
        print "DoReadMsr64() failed to write kdp_pkt_size"
        return result
    
    kgm_pkt = kern.GetValueFromAddress(data_address, 'kdp_readmsr64_req_t *')
    header_value = GetKDPPacketHeaderInt(
        request=GetEnumValue('kdp_req_t::KDP_READMSR64'),
        length=kdp_pkt_size)

    if not WriteInt64ToMemoryAddress(header_value, int(addressof(kgm_pkt.hdr))):
        print "DoReadMsr64() failed to write header_value"
        return result
    if not WriteInt32ToMemoryAddress(msr_address, int(addressof(kgm_pkt.address))):
        print "DoReadMsr64() failed to write msr_address"
        return result
    if not WriteInt16ToMemoryAddress(lcpu, int(addressof(kgm_pkt.lcpu))):
        print "DoReadMsr64() failed to write lcpu"
        return result
    if not WriteInt32ToMemoryAddress(1, input_address):
        print "DoReadMsr64() failed to write to input_address"
        return result

    result_pkt = Cast(addressof(kern.globals.manual_pkt.data),
        'kdp_readmsr64_reply_t *')
    if (result_pkt.error == 0):
        result = dereference(Cast(addressof(result_pkt.data), 'uint64_t *'))
    else:
        print "DoReadMsr64() result_pkt.error != 0"
    return result

def DoWriteMsr64(msr_address, lcpu, data):
    """ Write a 64-bit MSR
        Params: 
            msr_address: int - MSR index to write to
            lcpu: int - CPU identifier
            data: int - value to write
        Returns:
            True upon success, False if error
    """
    if "kdp" != GetConnectionProtocol():
        print "Target is not connected over kdp. Cannot write MSR."
        return False

    input_address = unsigned(addressof(kern.globals.manual_pkt.input))
    len_address = unsigned(addressof(kern.globals.manual_pkt.len))
    data_address = unsigned(addressof(kern.globals.manual_pkt.data))
    if not WriteInt32ToMemoryAddress(0, input_address):
        print "DoWriteMsr64() failed to write 0 to input_address"
        return False
    
    kdp_pkt_size = GetType('kdp_writemsr64_req_t').GetByteSize()
    if not WriteInt32ToMemoryAddress(kdp_pkt_size, len_address):
        print "DoWriteMsr64() failed to kdp_pkt_size"
        return False
    
    kgm_pkt = kern.GetValueFromAddress(data_address, 'kdp_writemsr64_req_t *')
    header_value = GetKDPPacketHeaderInt(
        request=GetEnumValue('kdp_req_t::KDP_WRITEMSR64'),
        length=kdp_pkt_size)
    
    if not WriteInt64ToMemoryAddress(header_value, int(addressof(kgm_pkt.hdr))):
        print "DoWriteMsr64() failed to write header_value"
        return False
    if not WriteInt32ToMemoryAddress(msr_address, int(addressof(kgm_pkt.address))):
        print "DoWriteMsr64() failed to write msr_address"
        return False
    if not WriteInt16ToMemoryAddress(lcpu, int(addressof(kgm_pkt.lcpu))):
        print "DoWriteMsr64() failed to write lcpu"
        return False
    if not WriteInt64ToMemoryAddress(data, int(addressof(kgm_pkt.data))):
        print "DoWriteMsr64() failed to write data"
        return False
    if not WriteInt32ToMemoryAddress(1, input_address):
        print "DoWriteMsr64() failed to write to input_address"
        return False

    result_pkt = Cast(addressof(kern.globals.manual_pkt.data),
        'kdp_writemsr64_reply_t *')
    if not result_pkt.error == 0:
        print "DoWriteMsr64() error received in reply packet"
        return False
    
    return True

@lldb_command('readmsr64')
def ReadMsr64(cmd_args=None):
    """ Read the specified MSR. The CPU can be optionally specified
        Syntax: readmsr64 <msr> [lcpu]
    """
    if cmd_args == None or len(cmd_args) < 1:
        print ReadMsr64.__doc__
        return
    
    msr_address = ArgumentStringToInt(cmd_args[0])
    if len(cmd_args) > 1:
        lcpu = ArgumentStringToInt(cmd_args[1])
    else:
        lcpu = int(xnudefines.lcpu_self)

    msr_value = DoReadMsr64(msr_address, lcpu)
    print "MSR[{:x}]: {:#016x}".format(msr_address, msr_value)

@lldb_command('writemsr64')
def WriteMsr64(cmd_args=None):
    """ Write the specified MSR. The CPU can be optionally specified
        Syntax: writemsr64 <msr> <value> [lcpu]
    """
    if cmd_args == None or len(cmd_args) < 2:
        print WriteMsr64.__doc__
        return
    msr_address = ArgumentStringToInt(cmd_args[0])
    write_val = ArgumentStringToInt(cmd_args[1])
    if len(cmd_args) > 2:
        lcpu = ArgumentStringToInt(cmd_args[2])
    else:
        lcpu = xnudefines.lcpu_self

    if not DoWriteMsr64(msr_address, lcpu, write_val):
        print "writemsr64 FAILED"

def GetKernelDebugBufferEntry(kdbg_entry):
    """ Extract the information from given kernel debug buffer entry and return the summary
        params:
            kdebug_entry - kd_buf - address of kernel debug buffer entry
        returns: 
            str - formatted output information of kd_buf entry
    """
    out_str = ""
    code_info_str = ""
    kdebug_entry = kern.GetValueFromAddress(kdbg_entry, 'kd_buf *')
    debugid     = kdebug_entry.debugid
    kdebug_arg1 = kdebug_entry.arg1
    kdebug_arg2 = kdebug_entry.arg2
    kdebug_arg3 = kdebug_entry.arg3
    kdebug_arg4 = kdebug_entry.arg4
    
    if kern.arch == 'x86_64' or kern.arch.startswith('arm64'):
        kdebug_cpu   = kdebug_entry.cpuid
        ts_hi        = (kdebug_entry.timestamp >> 32) & 0xFFFFFFFF
        ts_lo        = kdebug_entry.timestamp & 0xFFFFFFFF
    else:
        kdebug_cpu   = (kdebug_entry.timestamp >> 56)
        ts_hi        = (kdebug_entry.timestamp >> 32) & 0x00FFFFFF
        ts_lo        = kdebug_entry.timestamp & 0xFFFFFFFF
    
    kdebug_class    = (debugid >> 24) & 0x000FF
    kdebug_subclass = (debugid >> 16) & 0x000FF
    kdebug_code     = (debugid >>  2) & 0x03FFF
    kdebug_qual     = (debugid) & 0x00003
    
    if kdebug_qual == 0:
        kdebug_qual = '-'
    elif kdebug_qual == 1:
        kdebug_qual = 'S'
    elif kdebug_qual == 2:
        kdebug_qual = 'E'
    elif kdebug_qual == 3:
        kdebug_qual = '?'

    # preamble and qual
    out_str += "{:<#20x} {:>6d} {:>#12x} ".format(kdebug_entry, kdebug_cpu, kdebug_entry.arg5)
    out_str += " {:#010x}{:08x} {:>6s} ".format(ts_hi, ts_lo, kdebug_qual)
    
    # class
    kdbg_class = ""
    if kdebug_class == 1:
        kdbg_class = "MACH"
    elif kdebug_class == 2:
        kdbg_class = "NET "
    elif kdebug_class == 3:
        kdbg_class = "FS  "
    elif kdebug_class == 4:
        kdbg_class = "BSD "
    elif kdebug_class == 5:
        kdbg_class = "IOK "
    elif kdebug_class == 6:
        kdbg_class = "DRVR"
    elif kdebug_class == 7:
        kdbg_class = "TRAC"
    elif kdebug_class == 8:
        kdbg_class = "DLIL"
    elif kdebug_class == 9:
        kdbg_class = "WQ  "
    elif kdebug_class == 10:
        kdbg_class = "CS  "
    elif kdebug_class == 11:
        kdbg_class = "CG  "
    elif kdebug_class == 20:
        kdbg_class = "MISC"
    elif kdebug_class == 30:
        kdbg_class = "SEC "
    elif kdebug_class == 31:
        kdbg_class = "DYLD"
    elif kdebug_class == 32:
        kdbg_class = "QT  "
    elif kdebug_class == 33:
        kdbg_class = "APPS"
    elif kdebug_class == 34:
        kdbg_class = "LAUN"
    elif kdebug_class == 36:
        kdbg_class = "PPT "
    elif kdebug_class == 37:
        kdbg_class = "PERF"
    elif kdebug_class == 38:
        kdbg_class = "IMP "
    elif kdebug_class == 39:
        kdbg_class = "PCTL"
    elif kdebug_class == 40:
        kdbg_class = "BANK"
    elif kdebug_class == 41:
        kdbg_class = "XPC "
    elif kdebug_class == 42:
        kdbg_class = "ATM "
    elif kdebug_class == 128:
        kdbg_class = "ANS "
    elif kdebug_class == 129:
        kdbg_class = "SIO "
    elif kdebug_class == 130:
        kdbg_class = "SEP "
    elif kdebug_class == 131:
        kdbg_class = "ISP "
    elif kdebug_class == 132:
        kdbg_class = "OSCA"
    elif kdebug_class == 133:
        kdbg_class = "EGFX"
    elif kdebug_class == 255:
        kdbg_class = "MIG "
    else:
        out_str += "{:^#10x} ".format(kdebug_class)
    
    if kdbg_class:
        out_str += "{:^10s} ".format(kdbg_class)

    # subclass and code
    out_str += " {:>#5x} {:>8d}   ".format(kdebug_subclass, kdebug_code)

    # space for debugid-specific processing
    code_info_str += "arg1={:#010x} ".format(kdebug_arg1)
    code_info_str += "arg2={:#010x} ".format(kdebug_arg2)
    code_info_str += "arg3={:#010x} ".format(kdebug_arg3)
    code_info_str += "arg4={:#010x} ".format(kdebug_arg4)

    # finish up
    out_str += "{:<25s}\n".format(code_info_str)
    return out_str

@lldb_command('showkerneldebugbuffercpu')
@header("{0: ^20s} {1: >6s} {2: >12s} {3: ^20s} {4: >6s} {5: ^10s} {6: >5s} {7: >8s} {8: ^25s}".
    format('kd_buf', 'CPU', 'Thread', 'Timestamp', 'S/E', 'Class', 'Sub', 'Code', 'Code Specific Info'))
def ShowKernelDebugBufferCPU(cmd_args=None):
    """ Prints the last N entries in the kernel debug buffer for specified cpu
        Syntax: showkerneldebugbuffercpu <cpu_num> <count>
    """
    if cmd_args == None or len(cmd_args) < 2:
        raise ArgumentError("Invalid arguments passed.")
    
    out_str = ""
    kdbg_str = ""
    cpu_number = ArgumentStringToInt(cmd_args[0])
    entry_count = ArgumentStringToInt(cmd_args[1])
    debugentriesfound = 0
    if (kern.globals.kd_ctrl_page_trace.kdebug_flags & xnudefines.KDBG_BUFINIT):   
        out_str += ShowKernelDebugBufferCPU.header + "\n"
        if entry_count == 0:
            out_str += "<count> is 0, dumping 50 entries\n"
            entry_count = 50

        if cpu_number >= kern.globals.kd_ctrl_page_trace.kdebug_cpus:
            kdbg_str += "cpu number too big\n"
        else:
            kdbp = addressof(kern.globals.kd_data_page_trace.kdbip[cpu_number])
            kdsp = kdbp.kd_list_head
            while ((kdsp.raw != 0 and kdsp.raw != 0x00000000ffffffff) and (entry_count > 0)):
                kd_buffer = kern.globals.kd_data_page_trace.kd_bufs[kdsp.buffer_index]
                kdsp_actual = addressof(kd_buffer.kdsb_addr[kdsp.offset])
                if kdsp_actual.kds_readlast != kdsp_actual.kds_bufindx:
                    kds_buf = kdsp_actual.kds_records[kdsp_actual.kds_bufindx]
                    kds_bufptr = addressof(kds_buf)
                    while (entry_count > 0) and \
                        (unsigned(kds_bufptr) > unsigned(addressof(kdsp_actual.kds_records[kdsp_actual.kds_readlast]))):
                        kds_bufptr = kds_bufptr - sizeof(kds_buf)
                        entry_count = entry_count - 1
                        kdbg_str += GetKernelDebugBufferEntry(kds_bufptr)
                kdsp = kdsp_actual.kds_next
    else:
        kdbg_str += "Trace buffer not enabled for CPU {:d}\n".format(cpu_number)
    
    if kdbg_str:
        out_str += kdbg_str
        print out_str

@lldb_command('showkerneldebugbuffer')
def ShowKernelDebugBuffer(cmd_args=None):
    """ Prints the last N entries in the kernel debug buffer per cpu
        Syntax: showkerneldebugbuffer <count>
    """
    if cmd_args == None or len(cmd_args) < 1:
        raise ArgumentError("Invalid arguments passed.")
    
    if (kern.globals.kd_ctrl_page_trace.kdebug_flags & xnudefines.KDBG_BUFINIT):
        entrycount = ArgumentStringToInt(cmd_args[0])
        if entrycount == 0:
            print "<count> is 0, dumping 50 entries per cpu\n"
            entrycount = 50
        cpu_num = 0
        while cpu_num < kern.globals.kd_ctrl_page_trace.kdebug_cpus:
            ShowKernelDebugBufferCPU([str(cpu_num), str(entrycount)])
            cpu_num += 1
    else:
        print "Trace buffer not enabled\n"

@lldb_command('dumprawtracefile','U:')
def DumpRawTraceFile(cmd_args=[], cmd_options={}):
    """
        support for ktrace(1)

        NB: trace is not wordsize flexible, so use ktrace(1) compiled for the compatible model,
        e.g. if you dump from __LP64__ system, you will need to run ktrace(1) compiled __LP64__ to process the raw data file.

        read the kernel's debug trace buffer, and dump to a "raw" ktrace(1) file
        Usage: dumprawtracefile <output_filename>
            -U <uptime> : specify system uptime in nsec, obtained e.g. from paniclog
        Be patient, it is teh slow.

        cf. kdbg_read()\bsd/kern/kdebug.c
    """

    if (kern.globals.kd_ctrl_page_trace.kdebug_flags & xnudefines.KDBG_BUFINIT) == 0 :
        print "Trace buffer not enabled\n"
        return

    if ((kern.arch == "x86_64") or kern.arch.startswith("arm64")) :
        lp64 = True
    elif kern.arch == "arm" :
        lp64 = False
    else :
        print "unknown kern.arch {:s}\n".format(kern.arch)
        return

    # Various kern.globals are hashed by address, to
    #  a) avoid redundant kdp fetch from, and
    #  b) avoid all stores to
    # the target system kernel structures.
    # Stores to hashed structures remain strictly local to the lldb host,
    # they are never written back to the target.
    htab = {}

    if lp64 :
        KDBG_TIMESTAMP_MASK = 0xffffffffffffffff
        KDBG_CPU_SHIFT      = 0
    else :
        KDBG_TIMESTAMP_MASK = 0x00ffffffffffffff
        KDBG_CPU_SHIFT      = 56

    barrier_min     = 0
    barrier_max     = 0
    out_of_events       = False
    lostevents      = False
    lostevent_timestamp = 0
    lostevent_debugid   = (((xnudefines.DBG_TRACE & 0xff) << 24) | ((xnudefines.DBG_TRACE_INFO & 0xff) << 16) | ((2 & 0x3fff)  << 2)) # 0x01020008
    events_count_lost   = 0
    events_count_found  = 0

    opt_verbose = config['verbosity']
    opt_progress = (opt_verbose > vHUMAN) and (opt_verbose < vDETAIL)
    progress_count = 0
    progress_stride = 32

    output_filename = str(cmd_args[0])
    if opt_verbose > vHUMAN :
        print "output file : {:s}".format(output_filename)
    wfd = open(output_filename, "wb")

    uptime = long(-1)
    if "-U" in cmd_options:
        uptime = long(cmd_options["-U"])
    if opt_verbose > vHUMAN :
        print "uptime : {:d}".format(uptime)

    nkdbufs = kern.globals.kd_data_page_trace.nkdbufs

    kd_ctrl_page_trace = kern.globals.kd_ctrl_page_trace
    if not kd_ctrl_page_trace in htab :
        htab[kd_ctrl_page_trace] = kern.globals.kd_ctrl_page_trace

    if opt_verbose > vHUMAN :
        print "kd_data_page_trace_nkdbufs {0:#x}, enabled {1:#x}, flags {2:#x}, cpus {3:#x}".format(nkdbufs, htab[kd_ctrl_page_trace].enabled, htab[kd_ctrl_page_trace].kdebug_flags, htab[kd_ctrl_page_trace].kdebug_cpus)

    if nkdbufs == 0 :
        print "0 kd_data_page_trace_nkdbufs, nothing extracted"
        return

    if htab[kd_ctrl_page_trace].enabled != 0 :
        barrier_max = uptime & KDBG_TIMESTAMP_MASK

        f = htab[kd_ctrl_page_trace].kdebug_flags
        wrapped = f & xnudefines.KDBG_WRAPPED
    if wrapped != 0 :
        barrier_min = htab[kd_ctrl_page_trace].oldest_time
        htab[kd_ctrl_page_trace].kdebug_flags = htab[kd_ctrl_page_trace].kdebug_flags & ~xnudefines.KDBG_WRAPPED
        htab[kd_ctrl_page_trace].oldest_time = 0

        for cpu in range(htab[kd_ctrl_page_trace].kdebug_cpus) :
            kdbp = unsigned(addressof(kern.globals.kd_data_page_trace.kdbip[cpu]))
            if not kdbp in htab :
                htab[kdbp] = kern.globals.kd_data_page_trace.kdbip[cpu]

            kdsp = htab[kdbp].kd_list_head.raw
            if kdsp == xnudefines.KDS_PTR_NULL :
                continue

            ix = htab[kdbp].kd_list_head.buffer_index
            off = htab[kdbp].kd_list_head.offset
            kdsp_actual = unsigned(addressof(kern.globals.kd_data_page_trace.kd_bufs[ix].kdsb_addr[off]))
            if not kdsp_actual in htab :
                htab[kdsp_actual] = kern.globals.kd_data_page_trace.kd_bufs[ix].kdsb_addr[off]
            htab[kdsp_actual].kds_lostevents = False


    # generate trace file header; threadmap is stubbed/TBD
    version_no = xnudefines.RAW_VERSION1
    thread_count = 0
    TOD_secs = uptime
    TOD_usecs = 0
    header = struct.pack('IIqI', version_no, thread_count, TOD_secs, TOD_usecs)
    pad_bytes = 4096 - (len(header) & 4095)
    header += "\x00" * pad_bytes
    wfd.write(buffer(header))

    count = kern.globals.kd_data_page_trace.nkdbufs
    while count != 0 :
        tempbuf = ""
        tempbuf_number = 0
        tempbuf_count = min(count, kern.globals.kd_ctrl_page_trace.kdebug_kdcopybuf_count)

        # while space
        while tempbuf_count != 0 :

            if opt_progress == True :
                progress_count += 1
                if (progress_count % progress_stride) == 0 :
                    sys.stderr.write('.')
                    sys.stderr.flush()

            earliest_time = 0xffffffffffffffff
            min_kdbp = None
            min_cpu = 0

            # Check all CPUs
            for cpu in range(htab[kd_ctrl_page_trace].kdebug_cpus) :

                kdbp = unsigned(addressof(kern.globals.kd_data_page_trace.kdbip[cpu]))
                if not kdbp in htab :
                    htab[kdbp] = kern.globals.kd_data_page_trace.kdbip[cpu]

                # Skip CPUs without data.
                kdsp = htab[kdbp].kd_list_head
                if kdsp.raw == xnudefines.KDS_PTR_NULL :
                    continue

                kdsp_shadow = kdsp

                # Get from cpu data to buffer header to buffer
                ix = kdsp.buffer_index
                off = kdsp.offset
                kdsp_actual = unsigned(addressof(kern.globals.kd_data_page_trace.kd_bufs[ix].kdsb_addr[off]))
                if not kdsp_actual in htab :
                    htab[kdsp_actual] = kern.globals.kd_data_page_trace.kd_bufs[ix].kdsb_addr[off]

                kdsp_actual_shadow = kdsp_actual

                # Skip buffer if there are no events left.
                rcursor = htab[kdsp_actual].kds_readlast
                if rcursor == htab[kdsp_actual].kds_bufindx :
                    continue

                t = htab[kdsp_actual].kds_records[rcursor].timestamp & KDBG_TIMESTAMP_MASK

                # Ignore events that have aged out due to wrapping.
                goto_next_cpu = False;
                while (t < unsigned(barrier_min)) :
                    r = htab[kdsp_actual].kds_readlast
                    htab[kdsp_actual].kds_readlast = r + 1
                    rcursor = r + 1

                    if rcursor >= xnudefines.EVENTS_PER_STORAGE_UNIT :

                        kdsp = htab[kdbp].kd_list_head
                        if kdsp.raw == xnudefines.KDS_PTR_NULL :
                            goto_next_cpu = True
                            break

                        kdsp_shadow = kdsp;

                        ix  = kdsp.buffer_index
                        off = kdsp.offset
                        kdsp_actual = unsigned(addressof(kern.globals.kd_data_page_trace.kd_bufs[ix].kdsb_addr[off]))

                        kdsp_actual_shadow = kdsp_actual;
                        rcursor = htab[kdsp_actual].kds_readlast;

                    t = htab[kdsp_actual].kds_records[rcursor].timestamp & KDBG_TIMESTAMP_MASK

                if goto_next_cpu == True :
                    continue

                if (t > barrier_max) and (barrier_max > 0) :
                    # Need to flush IOPs again before we
                    # can sort any more data from the
                    # buffers.  
                    out_of_events = True
                    break

                if t < (htab[kdsp_actual].kds_timestamp & KDBG_TIMESTAMP_MASK) :
                    # indicates we've not yet completed filling
                    # in this event...
                    # this should only occur when we're looking
                    # at the buf that the record head is utilizing
                    # we'll pick these events up on the next
                    # call to kdbg_read
                    # we bail at this point so that we don't
                    # get an out-of-order timestream by continuing
                    # to read events from the other CPUs' timestream(s)
                    out_of_events = True
                    break

                if t < earliest_time :
                    earliest_time = t
                    min_kdbp = kdbp
                    min_cpu = cpu


            if (min_kdbp is None) or (out_of_events == True) :
                # all buffers ran empty
                                out_of_events = True
                                break

            kdsp = htab[min_kdbp].kd_list_head

            ix = kdsp.buffer_index
            off = kdsp.offset
            kdsp_actual = unsigned(addressof(kern.globals.kd_data_page_trace.kd_bufs[ix].kdsb_addr[off]))
            if not kdsp_actual in htab :
                htab[kdsp_actual] = kern.globals.kd_data_page_trace.kd_bufs[ix].kdsb_addr[off]

            # Copy earliest event into merged events scratch buffer.
            r = htab[kdsp_actual].kds_readlast
            htab[kdsp_actual].kds_readlast = r + 1
            e = htab[kdsp_actual].kds_records[r]

            # Concatenate event into buffer
            # XXX condition here is on __LP64__
            if lp64 :
                tempbuf += struct.pack('QQQQQQIIQ', 
                        unsigned(e.timestamp),
                        unsigned(e.arg1),
                        unsigned(e.arg2),
                        unsigned(e.arg3),
                        unsigned(e.arg4),
                        unsigned(e.arg5),
                        unsigned(e.debugid),
                        unsigned(e.cpuid),
                        unsigned(e.unused))
            else :
                tempbuf += struct.pack('QIIIIII',
                        unsigned(e.timestamp),
                        unsigned(e.arg1),
                        unsigned(e.arg2),
                        unsigned(e.arg3),
                        unsigned(e.arg4),
                        unsigned(e.arg5),
                        unsigned(e.debugid))

            # Watch for out of order timestamps
            if earliest_time < (htab[min_kdbp].kd_prev_timebase & KDBG_TIMESTAMP_MASK) :
                ## if so, use the previous timestamp + 1 cycle
                htab[min_kdbp].kd_prev_timebase += 1

                e.timestamp = htab[min_kdbp].kd_prev_timebase & KDBG_TIMESTAMP_MASK
                if not lp64:
                    e.timestamp |= (min_cpu << KDBG_CPU_SHIFT)
            else :
                htab[min_kdbp].kd_prev_timebase = earliest_time

            if opt_verbose >= vDETAIL :
                print "{0:#018x} {1:#018x} {2:#018x} {3:#018x} {4:#018x} {5:#018x} {6:#010x} {7:#010x} {8:#018x}".format(
                    e.timestamp, e.arg1, e.arg2, e.arg3, e.arg4, e.arg5, e.debugid, e.cpuid, e.unused)

            events_count_found += 1

            # nextevent:
            tempbuf_count -= 1
            tempbuf_number += 1

        if opt_progress == True :
            sys.stderr.write('\n')
            sys.stderr.flush()

        if opt_verbose > vHUMAN :
            print "events_count_lost {0:#x}, events_count_found {1:#x}, progress_count {2:#x}".format(events_count_lost, events_count_found, progress_count)

        # write trace events to output file
        if tempbuf_number != 0 :
            count -= tempbuf_number
            wfd.write(buffer(tempbuf))

        if out_of_events == True :
            # all trace buffers are empty
            if opt_verbose > vHUMAN :
                print "out of events"
            break

    wfd.close()

    return


def GetTimebaseInfo():
    timebase_key = 'kern.rtc_timebase'
    numer, denom = caching.GetStaticCacheData(timebase_key, (None, None))
    if not numer or not denom:
        if kern.arch == 'x86_64':
            numer = 1
            denom = 1
        else:
            rtclockdata_addr = kern.GetLoadAddressForSymbol('RTClockData')
            rtc = kern.GetValueFromAddress(
                rtclockdata_addr, 'struct _rtclock_data_ *')
            tb = rtc.rtc_timebase_const
            numer = tb.numer
            denom = tb.denom
        caching.SaveStaticCacheData(timebase_key, (numer, denom))
    return numer, denom


def PrintIteratedElem(i, elem, elem_type, do_summary, summary, regex):
    try:
        if do_summary and summary:
            s = summary(elem)
            if regex:
                if regex.match(s):
                    print "[{:d}] {:s}".format(i, s)
            else:
                print "[{:d}] {:s}".format(i, s)
        else:
            if regex:
                if regex.match(str(elem)):
                    print "[{:4d}] ({:s}){:#x}".format(i, elem_type, unsigned(elem))
            else:
                print "[{:4d}] ({:s}){:#x}".format(i, elem_type, unsigned(elem))
    except:
        print "Exception while looking at elem {:#x}".format(unsigned(elem))
        return

@lldb_command('q_iterate', "LQSG:")
def QIterate(cmd_args=None, cmd_options={}):
    """ Iterate over a LinkageChain or Queue (osfmk/kern/queue.h method 1 or 2 respectively)
        This is equivalent to the qe_foreach_element() macro
        usage:
            iterate [options] {queue_head_ptr} {element_type} {field_name}
        option:
            -L    iterate over a linkage chain (method 1) [default]
            -Q    iterate over a queue         (method 2)

            -S    auto-summarize known types
            -G    regex to filter the output
        e.g.
            iterate_linkage `&coalitions_q` 'coalition *' coalitions
    """
    if not cmd_args:
        raise ArgumentError("usage: iterate_linkage {queue_head_ptr} {element_type} {field_name}")

    qhead = kern.GetValueFromAddress(cmd_args[0], 'struct queue_entry *')
    if not qhead:
        raise ArgumentError("Unknown queue_head pointer: %r" % cmd_args)
    elem_type = cmd_args[1]
    field_name = cmd_args[2]
    if not elem_type or not field_name:
        raise ArgumentError("usage: iterate_linkage {queue_head_ptr} {element_type} {field_name}")

    do_queue_iterate = False
    do_linkage_iterate = True
    if "-Q" in cmd_options:
        do_queue_iterate = True
        do_linkage_iterate = False
    if "-L" in cmd_options:
        do_queue_iterate = False
        do_linkage_iterate = True

    do_summary = False
    if "-S" in cmd_options:
        do_summary = True
    regex = None
    if "-G" in cmd_options:
        regex = re.compile(".*{:s}.*".format(cmd_options["-G"]))
        print "Looking for: {:s}".format(regex.pattern)

    global lldb_summary_definitions
    summary = None
    if elem_type in lldb_summary_definitions:
        summary = lldb_summary_definitions[elem_type]
        if do_summary:
            print summary.header

    try:
        i = 0
        if do_linkage_iterate:
            for elem in IterateLinkageChain(qhead, elem_type, field_name):
                PrintIteratedElem(i, elem, elem_type, do_summary, summary, regex)
                i = i + 1
        elif do_queue_iterate:
            for elem in IterateQueue(qhead, elem_type, field_name):
                PrintIteratedElem(i, elem, elem_type, do_summary, summary, regex)
                i = i + 1
    except:
        print "Exception while looking at queue_head: {:#x}".format(unsigned(qhead))

@lldb_command('lbrbt')
def LBRBacktrace(cmd_args=None):
    """
        Prints symbolicated last branch records captured on Intel systems
        from a core file. Will not work on a live system.
        usage:
            lbrbt
        options:
            None
    """
    DecoratedLBRStack = SymbolicateLBR()
    if (DecoratedLBRStack):
        print(DecoratedLBRStack)

def SymbolicateLBR():
    lbr_size_offset = 5
    cpu_num_offset = 4
    LBRMagic = 0x5352424C
    
    try:
        phys_carveout_addr = kern.GetLoadAddressForSymbol("phys_carveout")
    except LookupError:
        print("Last Branch Recoreds not present in this core file")
        return None
    try:
        phys_carveout_md_addr = kern.GetLoadAddressForSymbol("phys_carveout_metadata")
    except LookupError:
        print("Last Branch Recoreds not present in this core file")
        return None

    metadata_ptr = kern.GetValueFromAddress(phys_carveout_md_addr, "uint64_t *")
    metadata = kern.GetValueFromAddress(unsigned(metadata_ptr[0]), "uint8_t *")
    carveout_ptr = kern.GetValueFromAddress(phys_carveout_addr, "uint64_t *")

    metadata_hdr = kern.GetValueFromAddress(unsigned(metadata_ptr[0]), "uint32_t *")
    if not (unsigned(metadata_hdr[0]) == LBRMagic):
        print("'LBRS' not found at beginning of phys_carveout section, cannot proceed.")
        return None

    lbr_records = unsigned(carveout_ptr[0])

    num_lbrs = int(metadata[lbr_size_offset])

    header_line = "".join("{:49s} -> {:s}\n".format("From", "To"))
    ncpus = int(metadata[cpu_num_offset])

    output_lines = [] 

    target = LazyTarget.GetTarget()

    for cpu in range(ncpus):
        start_addr_from = lbr_records + num_lbrs * 8 * cpu
        start_addr_to = start_addr_from + num_lbrs * 8 * ncpus
        from_lbr = kern.GetValueFromAddress(start_addr_from, "uint64_t *")
        to_lbr = kern.GetValueFromAddress(start_addr_to, "uint64_t *")
        for i in range(num_lbrs):
            if (from_lbr[i] == 0x0 or to_lbr[i] == 0x0):
                break
            ## Replace newline with space to include inlined functions
            ## in a trade off for longer output lines. 
            fprint = str(target.ResolveLoadAddress(int(from_lbr[i]))).replace('\n', ' ')
            tprint = str(target.ResolveLoadAddress(int(to_lbr[i]))).replace('\n', ' ')
            output_lines.append(''.join("({:x}) {:30s} -> ({:x}) {:30s}\n".format(from_lbr[i], fprint, to_lbr[i], tprint)))

    return header_line + ''.join(output_lines)