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llvm-project/lldb/source/Host/common/NativeProcessProtocol.cpp

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//===-- NativeProcessProtocol.cpp -----------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "lldb/Host/common/NativeProcessProtocol.h"
#include "lldb/Host/Host.h"
#include "lldb/Host/common/NativeBreakpointList.h"
#include "lldb/Host/common/NativeRegisterContext.h"
#include "lldb/Host/common/NativeThreadProtocol.h"
#include "lldb/Utility/LLDBAssert.h"
#include "lldb/Utility/Log.h"
#include "lldb/Utility/State.h"
#include "lldb/lldb-enumerations.h"
#include "llvm/Support/Process.h"
using namespace lldb;
using namespace lldb_private;
// NativeProcessProtocol Members
NativeProcessProtocol::NativeProcessProtocol(lldb::pid_t pid, int terminal_fd,
NativeDelegate &delegate)
: m_pid(pid), m_terminal_fd(terminal_fd) {
bool registered = RegisterNativeDelegate(delegate);
assert(registered);
(void)registered;
}
lldb_private::Status NativeProcessProtocol::Interrupt() {
Status error;
#if !defined(SIGSTOP)
error.SetErrorString("local host does not support signaling");
return error;
#else
return Signal(SIGSTOP);
#endif
}
Status NativeProcessProtocol::IgnoreSignals(llvm::ArrayRef<int> signals) {
m_signals_to_ignore.clear();
m_signals_to_ignore.insert(signals.begin(), signals.end());
return Status();
}
lldb_private::Status
NativeProcessProtocol::GetMemoryRegionInfo(lldb::addr_t load_addr,
MemoryRegionInfo &range_info) {
// Default: not implemented.
return Status("not implemented");
}
llvm::Optional<WaitStatus> NativeProcessProtocol::GetExitStatus() {
if (m_state == lldb::eStateExited)
return m_exit_status;
return llvm::None;
}
bool NativeProcessProtocol::SetExitStatus(WaitStatus status,
bool bNotifyStateChange) {
Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
LLDB_LOG(log, "status = {0}, notify = {1}", status, bNotifyStateChange);
// Exit status already set
if (m_state == lldb::eStateExited) {
if (m_exit_status)
LLDB_LOG(log, "exit status already set to {0}", *m_exit_status);
else
LLDB_LOG(log, "state is exited, but status not set");
return false;
}
m_state = lldb::eStateExited;
m_exit_status = status;
if (bNotifyStateChange)
SynchronouslyNotifyProcessStateChanged(lldb::eStateExited);
return true;
}
NativeThreadProtocol *NativeProcessProtocol::GetThreadAtIndex(uint32_t idx) {
std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
if (idx < m_threads.size())
return m_threads[idx].get();
return nullptr;
}
NativeThreadProtocol *
NativeProcessProtocol::GetThreadByIDUnlocked(lldb::tid_t tid) {
for (const auto &thread : m_threads) {
if (thread->GetID() == tid)
return thread.get();
}
return nullptr;
}
NativeThreadProtocol *NativeProcessProtocol::GetThreadByID(lldb::tid_t tid) {
std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
return GetThreadByIDUnlocked(tid);
}
bool NativeProcessProtocol::IsAlive() const {
return m_state != eStateDetached && m_state != eStateExited &&
m_state != eStateInvalid && m_state != eStateUnloaded;
}
const NativeWatchpointList::WatchpointMap &
NativeProcessProtocol::GetWatchpointMap() const {
return m_watchpoint_list.GetWatchpointMap();
}
llvm::Optional<std::pair<uint32_t, uint32_t>>
NativeProcessProtocol::GetHardwareDebugSupportInfo() const {
Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
// get any thread
NativeThreadProtocol *thread(
const_cast<NativeProcessProtocol *>(this)->GetThreadAtIndex(0));
if (!thread) {
LLDB_LOG(log, "failed to find a thread to grab a NativeRegisterContext!");
return llvm::None;
}
NativeRegisterContext &reg_ctx = thread->GetRegisterContext();
return std::make_pair(reg_ctx.NumSupportedHardwareBreakpoints(),
reg_ctx.NumSupportedHardwareWatchpoints());
}
Status NativeProcessProtocol::SetWatchpoint(lldb::addr_t addr, size_t size,
uint32_t watch_flags,
bool hardware) {
// This default implementation assumes setting the watchpoint for the process
// will require setting the watchpoint for each of the threads. Furthermore,
// it will track watchpoints set for the process and will add them to each
// thread that is attached to via the (FIXME implement) OnThreadAttached ()
// method.
Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
// Update the thread list
UpdateThreads();
// Keep track of the threads we successfully set the watchpoint for. If one
// of the thread watchpoint setting operations fails, back off and remove the
// watchpoint for all the threads that were successfully set so we get back
// to a consistent state.
std::vector<NativeThreadProtocol *> watchpoint_established_threads;
// Tell each thread to set a watchpoint. In the event that hardware
// watchpoints are requested but the SetWatchpoint fails, try to set a
// software watchpoint as a fallback. It's conceivable that if there are
// more threads than hardware watchpoints available, some of the threads will
// fail to set hardware watchpoints while software ones may be available.
std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
for (const auto &thread : m_threads) {
assert(thread && "thread list should not have a NULL thread!");
Status thread_error =
thread->SetWatchpoint(addr, size, watch_flags, hardware);
if (thread_error.Fail() && hardware) {
// Try software watchpoints since we failed on hardware watchpoint
// setting and we may have just run out of hardware watchpoints.
thread_error = thread->SetWatchpoint(addr, size, watch_flags, false);
if (thread_error.Success())
LLDB_LOG(log,
"hardware watchpoint requested but software watchpoint set");
}
if (thread_error.Success()) {
// Remember that we set this watchpoint successfully in case we need to
// clear it later.
watchpoint_established_threads.push_back(thread.get());
} else {
// Unset the watchpoint for each thread we successfully set so that we
// get back to a consistent state of "not set" for the watchpoint.
for (auto unwatch_thread_sp : watchpoint_established_threads) {
Status remove_error = unwatch_thread_sp->RemoveWatchpoint(addr);
if (remove_error.Fail())
LLDB_LOG(log, "RemoveWatchpoint failed for pid={0}, tid={1}: {2}",
GetID(), unwatch_thread_sp->GetID(), remove_error);
}
return thread_error;
}
}
return m_watchpoint_list.Add(addr, size, watch_flags, hardware);
}
Status NativeProcessProtocol::RemoveWatchpoint(lldb::addr_t addr) {
// Update the thread list
UpdateThreads();
Status overall_error;
std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
for (const auto &thread : m_threads) {
assert(thread && "thread list should not have a NULL thread!");
const Status thread_error = thread->RemoveWatchpoint(addr);
if (thread_error.Fail()) {
// Keep track of the first thread error if any threads fail. We want to
// try to remove the watchpoint from every thread, though, even if one or
// more have errors.
if (!overall_error.Fail())
overall_error = thread_error;
}
}
const Status error = m_watchpoint_list.Remove(addr);
return overall_error.Fail() ? overall_error : error;
}
const HardwareBreakpointMap &
NativeProcessProtocol::GetHardwareBreakpointMap() const {
return m_hw_breakpoints_map;
}
Status NativeProcessProtocol::SetHardwareBreakpoint(lldb::addr_t addr,
size_t size) {
// This default implementation assumes setting a hardware breakpoint for this
// process will require setting same hardware breakpoint for each of its
// existing threads. New thread will do the same once created.
Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
// Update the thread list
UpdateThreads();
// Exit here if target does not have required hardware breakpoint capability.
auto hw_debug_cap = GetHardwareDebugSupportInfo();
if (hw_debug_cap == llvm::None || hw_debug_cap->first == 0 ||
hw_debug_cap->first <= m_hw_breakpoints_map.size())
return Status("Target does not have required no of hardware breakpoints");
// Vector below stores all thread pointer for which we have we successfully
// set this hardware breakpoint. If any of the current process threads fails
// to set this hardware breakpoint then roll back and remove this breakpoint
// for all the threads that had already set it successfully.
std::vector<NativeThreadProtocol *> breakpoint_established_threads;
// Request to set a hardware breakpoint for each of current process threads.
std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
for (const auto &thread : m_threads) {
assert(thread && "thread list should not have a NULL thread!");
Status thread_error = thread->SetHardwareBreakpoint(addr, size);
if (thread_error.Success()) {
// Remember that we set this breakpoint successfully in case we need to
// clear it later.
breakpoint_established_threads.push_back(thread.get());
} else {
// Unset the breakpoint for each thread we successfully set so that we
// get back to a consistent state of "not set" for this hardware
// breakpoint.
for (auto rollback_thread_sp : breakpoint_established_threads) {
Status remove_error =
rollback_thread_sp->RemoveHardwareBreakpoint(addr);
if (remove_error.Fail())
LLDB_LOG(log,
"RemoveHardwareBreakpoint failed for pid={0}, tid={1}: {2}",
GetID(), rollback_thread_sp->GetID(), remove_error);
}
return thread_error;
}
}
// Register new hardware breakpoint into hardware breakpoints map of current
// process.
m_hw_breakpoints_map[addr] = {addr, size};
return Status();
}
Status NativeProcessProtocol::RemoveHardwareBreakpoint(lldb::addr_t addr) {
// Update the thread list
UpdateThreads();
Status error;
std::lock_guard<std::recursive_mutex> guard(m_threads_mutex);
for (const auto &thread : m_threads) {
assert(thread && "thread list should not have a NULL thread!");
error = thread->RemoveHardwareBreakpoint(addr);
}
// Also remove from hardware breakpoint map of current process.
m_hw_breakpoints_map.erase(addr);
return error;
}
bool NativeProcessProtocol::RegisterNativeDelegate(
NativeDelegate &native_delegate) {
std::lock_guard<std::recursive_mutex> guard(m_delegates_mutex);
if (std::find(m_delegates.begin(), m_delegates.end(), &native_delegate) !=
m_delegates.end())
return false;
m_delegates.push_back(&native_delegate);
native_delegate.InitializeDelegate(this);
return true;
}
bool NativeProcessProtocol::UnregisterNativeDelegate(
NativeDelegate &native_delegate) {
std::lock_guard<std::recursive_mutex> guard(m_delegates_mutex);
const auto initial_size = m_delegates.size();
m_delegates.erase(
remove(m_delegates.begin(), m_delegates.end(), &native_delegate),
m_delegates.end());
// We removed the delegate if the count of delegates shrank after removing
// all copies of the given native_delegate from the vector.
return m_delegates.size() < initial_size;
}
void NativeProcessProtocol::SynchronouslyNotifyProcessStateChanged(
lldb::StateType state) {
Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
std::lock_guard<std::recursive_mutex> guard(m_delegates_mutex);
for (auto native_delegate : m_delegates)
native_delegate->ProcessStateChanged(this, state);
if (log) {
if (!m_delegates.empty()) {
LLDB_LOGF(log,
"NativeProcessProtocol::%s: sent state notification [%s] "
"from process %" PRIu64,
__FUNCTION__, lldb_private::StateAsCString(state), GetID());
} else {
LLDB_LOGF(log,
"NativeProcessProtocol::%s: would send state notification "
"[%s] from process %" PRIu64 ", but no delegates",
__FUNCTION__, lldb_private::StateAsCString(state), GetID());
}
}
}
void NativeProcessProtocol::NotifyDidExec() {
Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
LLDB_LOGF(log, "NativeProcessProtocol::%s - preparing to call delegates",
__FUNCTION__);
{
std::lock_guard<std::recursive_mutex> guard(m_delegates_mutex);
for (auto native_delegate : m_delegates)
native_delegate->DidExec(this);
}
}
Status NativeProcessProtocol::SetSoftwareBreakpoint(lldb::addr_t addr,
uint32_t size_hint) {
Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_BREAKPOINTS));
LLDB_LOG(log, "addr = {0:x}, size_hint = {1}", addr, size_hint);
auto it = m_software_breakpoints.find(addr);
if (it != m_software_breakpoints.end()) {
++it->second.ref_count;
return Status();
}
auto expected_bkpt = EnableSoftwareBreakpoint(addr, size_hint);
if (!expected_bkpt)
return Status(expected_bkpt.takeError());
m_software_breakpoints.emplace(addr, std::move(*expected_bkpt));
return Status();
}
Status NativeProcessProtocol::RemoveSoftwareBreakpoint(lldb::addr_t addr) {
Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_BREAKPOINTS));
LLDB_LOG(log, "addr = {0:x}", addr);
auto it = m_software_breakpoints.find(addr);
if (it == m_software_breakpoints.end())
return Status("Breakpoint not found.");
assert(it->second.ref_count > 0);
if (--it->second.ref_count > 0)
return Status();
// This is the last reference. Let's remove the breakpoint.
Status error;
// Clear a software breakpoint instruction
llvm::SmallVector<uint8_t, 4> curr_break_op(
it->second.breakpoint_opcodes.size(), 0);
// Read the breakpoint opcode
size_t bytes_read = 0;
error =
ReadMemory(addr, curr_break_op.data(), curr_break_op.size(), bytes_read);
if (error.Fail() || bytes_read < curr_break_op.size()) {
return Status("addr=0x%" PRIx64
": tried to read %zu bytes but only read %zu",
addr, curr_break_op.size(), bytes_read);
}
const auto &saved = it->second.saved_opcodes;
// Make sure the breakpoint opcode exists at this address
if (makeArrayRef(curr_break_op) != it->second.breakpoint_opcodes) {
if (curr_break_op != it->second.saved_opcodes)
return Status("Original breakpoint trap is no longer in memory.");
LLDB_LOG(log,
"Saved opcodes ({0:@[x]}) have already been restored at {1:x}.",
llvm::make_range(saved.begin(), saved.end()), addr);
} else {
// We found a valid breakpoint opcode at this address, now restore the
// saved opcode.
size_t bytes_written = 0;
error = WriteMemory(addr, saved.data(), saved.size(), bytes_written);
if (error.Fail() || bytes_written < saved.size()) {
return Status("addr=0x%" PRIx64
": tried to write %zu bytes but only wrote %zu",
addr, saved.size(), bytes_written);
}
// Verify that our original opcode made it back to the inferior
llvm::SmallVector<uint8_t, 4> verify_opcode(saved.size(), 0);
size_t verify_bytes_read = 0;
error = ReadMemory(addr, verify_opcode.data(), verify_opcode.size(),
verify_bytes_read);
if (error.Fail() || verify_bytes_read < verify_opcode.size()) {
return Status("addr=0x%" PRIx64
": tried to read %zu verification bytes but only read %zu",
addr, verify_opcode.size(), verify_bytes_read);
}
if (verify_opcode != saved)
LLDB_LOG(log, "Restoring bytes at {0:x}: {1:@[x]}", addr,
llvm::make_range(saved.begin(), saved.end()));
}
m_software_breakpoints.erase(it);
return Status();
}
llvm::Expected<NativeProcessProtocol::SoftwareBreakpoint>
NativeProcessProtocol::EnableSoftwareBreakpoint(lldb::addr_t addr,
uint32_t size_hint) {
Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_BREAKPOINTS));
auto expected_trap = GetSoftwareBreakpointTrapOpcode(size_hint);
if (!expected_trap)
return expected_trap.takeError();
llvm::SmallVector<uint8_t, 4> saved_opcode_bytes(expected_trap->size(), 0);
// Save the original opcodes by reading them so we can restore later.
size_t bytes_read = 0;
Status error = ReadMemory(addr, saved_opcode_bytes.data(),
saved_opcode_bytes.size(), bytes_read);
if (error.Fail())
return error.ToError();
// Ensure we read as many bytes as we expected.
if (bytes_read != saved_opcode_bytes.size()) {
return llvm::createStringError(
llvm::inconvertibleErrorCode(),
"Failed to read memory while attempting to set breakpoint: attempted "
"to read {0} bytes but only read {1}.",
saved_opcode_bytes.size(), bytes_read);
}
LLDB_LOG(
log, "Overwriting bytes at {0:x}: {1:@[x]}", addr,
llvm::make_range(saved_opcode_bytes.begin(), saved_opcode_bytes.end()));
// Write a software breakpoint in place of the original opcode.
size_t bytes_written = 0;
error = WriteMemory(addr, expected_trap->data(), expected_trap->size(),
bytes_written);
if (error.Fail())
return error.ToError();
// Ensure we wrote as many bytes as we expected.
if (bytes_written != expected_trap->size()) {
return llvm::createStringError(
llvm::inconvertibleErrorCode(),
"Failed write memory while attempting to set "
"breakpoint: attempted to write {0} bytes but only wrote {1}",
expected_trap->size(), bytes_written);
}
llvm::SmallVector<uint8_t, 4> verify_bp_opcode_bytes(expected_trap->size(),
0);
size_t verify_bytes_read = 0;
error = ReadMemory(addr, verify_bp_opcode_bytes.data(),
verify_bp_opcode_bytes.size(), verify_bytes_read);
if (error.Fail())
return error.ToError();
// Ensure we read as many verification bytes as we expected.
if (verify_bytes_read != verify_bp_opcode_bytes.size()) {
return llvm::createStringError(
llvm::inconvertibleErrorCode(),
"Failed to read memory while "
"attempting to verify breakpoint: attempted to read {0} bytes "
"but only read {1}",
verify_bp_opcode_bytes.size(), verify_bytes_read);
}
if (llvm::makeArrayRef(verify_bp_opcode_bytes.data(), verify_bytes_read) !=
*expected_trap) {
return llvm::createStringError(
llvm::inconvertibleErrorCode(),
"Verification of software breakpoint "
"writing failed - trap opcodes not successfully read back "
"after writing when setting breakpoint at {0:x}",
addr);
}
LLDB_LOG(log, "addr = {0:x}: SUCCESS", addr);
return SoftwareBreakpoint{1, saved_opcode_bytes, *expected_trap};
}
llvm::Expected<llvm::ArrayRef<uint8_t>>
NativeProcessProtocol::GetSoftwareBreakpointTrapOpcode(size_t size_hint) {
static const uint8_t g_aarch64_opcode[] = {0x00, 0x00, 0x20, 0xd4};
static const uint8_t g_i386_opcode[] = {0xCC};
static const uint8_t g_mips64_opcode[] = {0x00, 0x00, 0x00, 0x0d};
static const uint8_t g_mips64el_opcode[] = {0x0d, 0x00, 0x00, 0x00};
static const uint8_t g_s390x_opcode[] = {0x00, 0x01};
static const uint8_t g_ppc64le_opcode[] = {0x08, 0x00, 0xe0, 0x7f}; // trap
switch (GetArchitecture().GetMachine()) {
case llvm::Triple::aarch64:
case llvm::Triple::aarch64_32:
return llvm::makeArrayRef(g_aarch64_opcode);
case llvm::Triple::x86:
case llvm::Triple::x86_64:
return llvm::makeArrayRef(g_i386_opcode);
case llvm::Triple::mips:
case llvm::Triple::mips64:
return llvm::makeArrayRef(g_mips64_opcode);
case llvm::Triple::mipsel:
case llvm::Triple::mips64el:
return llvm::makeArrayRef(g_mips64el_opcode);
case llvm::Triple::systemz:
return llvm::makeArrayRef(g_s390x_opcode);
case llvm::Triple::ppc64le:
return llvm::makeArrayRef(g_ppc64le_opcode);
default:
return llvm::createStringError(llvm::inconvertibleErrorCode(),
"CPU type not supported!");
}
}
size_t NativeProcessProtocol::GetSoftwareBreakpointPCOffset() {
switch (GetArchitecture().GetMachine()) {
case llvm::Triple::x86:
case llvm::Triple::x86_64:
case llvm::Triple::systemz:
// These architectures report increment the PC after breakpoint is hit.
return cantFail(GetSoftwareBreakpointTrapOpcode(0)).size();
case llvm::Triple::arm:
case llvm::Triple::aarch64:
case llvm::Triple::aarch64_32:
case llvm::Triple::mips64:
case llvm::Triple::mips64el:
case llvm::Triple::mips:
case llvm::Triple::mipsel:
case llvm::Triple::ppc64le:
// On these architectures the PC doesn't get updated for breakpoint hits.
return 0;
default:
llvm_unreachable("CPU type not supported!");
}
}
void NativeProcessProtocol::FixupBreakpointPCAsNeeded(
NativeThreadProtocol &thread) {
Log *log = GetLogIfAnyCategoriesSet(LIBLLDB_LOG_BREAKPOINTS);
Status error;
// Find out the size of a breakpoint (might depend on where we are in the
// code).
NativeRegisterContext &context = thread.GetRegisterContext();
uint32_t breakpoint_size = GetSoftwareBreakpointPCOffset();
LLDB_LOG(log, "breakpoint size: {0}", breakpoint_size);
if (breakpoint_size == 0)
return;
// First try probing for a breakpoint at a software breakpoint location: PC -
// breakpoint size.
const lldb::addr_t initial_pc_addr = context.GetPCfromBreakpointLocation();
lldb::addr_t breakpoint_addr = initial_pc_addr;
// Do not allow breakpoint probe to wrap around.
if (breakpoint_addr >= breakpoint_size)
breakpoint_addr -= breakpoint_size;
if (m_software_breakpoints.count(breakpoint_addr) == 0) {
// We didn't find one at a software probe location. Nothing to do.
LLDB_LOG(log,
"pid {0} no lldb software breakpoint found at current pc with "
"adjustment: {1}",
GetID(), breakpoint_addr);
return;
}
//
// We have a software breakpoint and need to adjust the PC.
//
// Change the program counter.
LLDB_LOG(log, "pid {0} tid {1}: changing PC from {2:x} to {3:x}", GetID(),
thread.GetID(), initial_pc_addr, breakpoint_addr);
error = context.SetPC(breakpoint_addr);
if (error.Fail()) {
// This can happen in case the process was killed between the time we read
// the PC and when we are updating it. There's nothing better to do than to
// swallow the error.
LLDB_LOG(log, "pid {0} tid {1}: failed to set PC: {2}", GetID(),
thread.GetID(), error);
}
}
Status NativeProcessProtocol::RemoveBreakpoint(lldb::addr_t addr,
bool hardware) {
if (hardware)
return RemoveHardwareBreakpoint(addr);
else
return RemoveSoftwareBreakpoint(addr);
}
Status NativeProcessProtocol::ReadMemoryWithoutTrap(lldb::addr_t addr,
void *buf, size_t size,
size_t &bytes_read) {
Status error = ReadMemory(addr, buf, size, bytes_read);
if (error.Fail())
return error;
auto data =
llvm::makeMutableArrayRef(static_cast<uint8_t *>(buf), bytes_read);
for (const auto &pair : m_software_breakpoints) {
lldb::addr_t bp_addr = pair.first;
auto saved_opcodes = makeArrayRef(pair.second.saved_opcodes);
if (bp_addr + saved_opcodes.size() < addr || addr + bytes_read <= bp_addr)
continue; // Breapoint not in range, ignore
if (bp_addr < addr) {
saved_opcodes = saved_opcodes.drop_front(addr - bp_addr);
bp_addr = addr;
}
auto bp_data = data.drop_front(bp_addr - addr);
std::copy_n(saved_opcodes.begin(),
std::min(saved_opcodes.size(), bp_data.size()),
bp_data.begin());
}
return Status();
}
llvm::Expected<llvm::StringRef>
NativeProcessProtocol::ReadCStringFromMemory(lldb::addr_t addr, char *buffer,
size_t max_size,
size_t &total_bytes_read) {
static const size_t cache_line_size =
llvm::sys::Process::getPageSizeEstimate();
size_t bytes_read = 0;
size_t bytes_left = max_size;
addr_t curr_addr = addr;
size_t string_size;
char *curr_buffer = buffer;
total_bytes_read = 0;
Status status;
while (bytes_left > 0 && status.Success()) {
addr_t cache_line_bytes_left =
cache_line_size - (curr_addr % cache_line_size);
addr_t bytes_to_read = std::min<addr_t>(bytes_left, cache_line_bytes_left);
status = ReadMemory(curr_addr, static_cast<void *>(curr_buffer),
bytes_to_read, bytes_read);
if (bytes_read == 0)
break;
void *str_end = std::memchr(curr_buffer, '\0', bytes_read);
if (str_end != nullptr) {
total_bytes_read =
static_cast<size_t>((static_cast<char *>(str_end) - buffer + 1));
status.Clear();
break;
}
total_bytes_read += bytes_read;
curr_buffer += bytes_read;
curr_addr += bytes_read;
bytes_left -= bytes_read;
}
string_size = total_bytes_read - 1;
// Make sure we return a null terminated string.
if (bytes_left == 0 && max_size > 0 && buffer[max_size - 1] != '\0') {
buffer[max_size - 1] = '\0';
total_bytes_read--;
}
if (!status.Success())
return status.ToError();
return llvm::StringRef(buffer, string_size);
}
lldb::StateType NativeProcessProtocol::GetState() const {
std::lock_guard<std::recursive_mutex> guard(m_state_mutex);
return m_state;
}
void NativeProcessProtocol::SetState(lldb::StateType state,
bool notify_delegates) {
std::lock_guard<std::recursive_mutex> guard(m_state_mutex);
if (state == m_state)
return;
m_state = state;
if (StateIsStoppedState(state, false)) {
++m_stop_id;
// Give process a chance to do any stop id bump processing, such as
// clearing cached data that is invalidated each time the process runs.
// Note if/when we support some threads running, we'll end up needing to
// manage this per thread and per process.
DoStopIDBumped(m_stop_id);
}
// Optionally notify delegates of the state change.
if (notify_delegates)
SynchronouslyNotifyProcessStateChanged(state);
}
uint32_t NativeProcessProtocol::GetStopID() const {
std::lock_guard<std::recursive_mutex> guard(m_state_mutex);
return m_stop_id;
}
void NativeProcessProtocol::DoStopIDBumped(uint32_t /* newBumpId */) {
// Default implementation does nothing.
}
NativeProcessProtocol::Factory::~Factory() = default;
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