llvm-project/lldb/unittests/TestingSupport/Host/NativeProcessTestUtils.h
Pavel Labath 2c4226f8ac [lldb-server][linux] Add ability to allocate memory
This patch adds support for the _M and _m gdb-remote packets, which
(de)allocate memory in the inferior. This works by "injecting" a
m(un)map syscall into the inferior. This consists of:
- finding an executable page of memory
- writing the syscall opcode to it
- setting up registers according to the os syscall convention
- single stepping over the syscall

The advantage of this approach over calling the mmap function is that
this works even in case the mmap function is buggy or unavailable. The
disadvantage is it is more platform-dependent, which is why this patch
only works on X86 (_32 and _64) right now. Adding support for other
linux architectures should be easy and consist of defining the
appropriate syscall constants. Adding support for other OSes depends on
the its ability to do a similar trick.

Differential Revision: https://reviews.llvm.org/D89124
2020-10-14 15:02:09 +02:00

148 lines
5.3 KiB
C++

//===-- NativeProcessTestUtils.cpp ------------------------------*- C++ -*-===//
//
// 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
//
//===----------------------------------------------------------------------===//
#ifndef LLDB_UNITTESTS_TESTINGSUPPORT_HOST_NATIVEPROCESSTESTUTILS_H
#define LLDB_UNITTESTS_TESTINGSUPPORT_HOST_NATIVEPROCESSTESTUTILS_H
#include "lldb/Host/common/NativeProcessProtocol.h"
#include "llvm/Testing/Support/Error.h"
#include "gmock/gmock.h"
using namespace lldb_private;
using namespace lldb;
using namespace testing;
namespace lldb_private {
class MockDelegate : public NativeProcessProtocol::NativeDelegate {
public:
MOCK_METHOD1(InitializeDelegate, void(NativeProcessProtocol *Process));
MOCK_METHOD2(ProcessStateChanged,
void(NativeProcessProtocol *Process, StateType State));
MOCK_METHOD1(DidExec, void(NativeProcessProtocol *Process));
};
// NB: This class doesn't use the override keyword to avoid
// -Winconsistent-missing-override warnings from the compiler. The
// inconsistency comes from the overriding definitions in the MOCK_*** macros.
template <typename T> class MockProcess : public T {
public:
MockProcess(NativeProcessProtocol::NativeDelegate &Delegate,
const ArchSpec &Arch, lldb::pid_t Pid = 1)
: T(Pid, -1, Delegate), Arch(Arch) {}
MOCK_METHOD1(Resume, Status(const ResumeActionList &ResumeActions));
MOCK_METHOD0(Halt, Status());
MOCK_METHOD0(Detach, Status());
MOCK_METHOD1(Signal, Status(int Signo));
MOCK_METHOD0(Kill, Status());
MOCK_METHOD0(GetSharedLibraryInfoAddress, addr_t());
MOCK_METHOD0(UpdateThreads, size_t());
MOCK_CONST_METHOD0(GetAuxvData,
llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>());
MOCK_METHOD2(GetLoadedModuleFileSpec,
Status(const char *ModulePath, FileSpec &Spec));
MOCK_METHOD2(GetFileLoadAddress,
Status(const llvm::StringRef &FileName, addr_t &Addr));
const ArchSpec &GetArchitecture() const /*override*/ { return Arch; }
Status SetBreakpoint(lldb::addr_t Addr, uint32_t Size,
bool Hardware) /*override*/ {
if (Hardware)
return this->SetHardwareBreakpoint(Addr, Size);
else
return this->SetSoftwareBreakpoint(Addr, Size);
}
// Redirect base class Read/Write Memory methods to functions whose signatures
// are more mock-friendly.
Status ReadMemory(addr_t Addr, void *Buf, size_t Size,
size_t &BytesRead) /*override*/ {
auto ExpectedMemory = this->ReadMemory(Addr, Size);
if (!ExpectedMemory) {
BytesRead = 0;
return Status(ExpectedMemory.takeError());
}
BytesRead = ExpectedMemory->size();
assert(BytesRead <= Size);
std::memcpy(Buf, ExpectedMemory->data(), BytesRead);
return Status();
}
Status WriteMemory(addr_t Addr, const void *Buf, size_t Size,
size_t &BytesWritten) /*override*/ {
auto ExpectedBytes = this->WriteMemory(
Addr, llvm::makeArrayRef(static_cast<const uint8_t *>(Buf), Size));
if (!ExpectedBytes) {
BytesWritten = 0;
return Status(ExpectedBytes.takeError());
}
BytesWritten = *ExpectedBytes;
return Status();
}
MOCK_METHOD2(ReadMemory,
llvm::Expected<std::vector<uint8_t>>(addr_t Addr, size_t Size));
MOCK_METHOD2(WriteMemory,
llvm::Expected<size_t>(addr_t Addr,
llvm::ArrayRef<uint8_t> Data));
using T::GetSoftwareBreakpointTrapOpcode;
llvm::Expected<std::vector<uint8_t>> ReadMemoryWithoutTrap(addr_t Addr,
size_t Size) {
std::vector<uint8_t> Data(Size, 0);
size_t BytesRead;
Status ST =
T::ReadMemoryWithoutTrap(Addr, Data.data(), Data.size(), BytesRead);
if (ST.Fail())
return ST.ToError();
Data.resize(BytesRead);
return std::move(Data);
}
private:
ArchSpec Arch;
};
class FakeMemory {
public:
FakeMemory(llvm::ArrayRef<uint8_t> Data, addr_t start_addr = 0)
: Data(Data), m_start_addr(start_addr) {}
FakeMemory(const void *Data, size_t data_size, addr_t start_addr = 0)
: Data((const uint8_t *)Data, ((const uint8_t *)Data) + data_size),
m_start_addr(start_addr) {}
llvm::Expected<std::vector<uint8_t>> Read(addr_t Addr, size_t Size) {
Addr -= m_start_addr;
if (Addr >= Data.size())
return llvm::createStringError(llvm::inconvertibleErrorCode(),
"Address out of range.");
Size = std::min(Size, Data.size() - (size_t)Addr);
auto Begin = std::next(Data.begin(), Addr);
return std::vector<uint8_t>(Begin, std::next(Begin, Size));
}
llvm::Expected<size_t> Write(addr_t Addr, llvm::ArrayRef<uint8_t> Chunk) {
Addr -= m_start_addr;
if (Addr >= Data.size())
return llvm::createStringError(llvm::inconvertibleErrorCode(),
"Address out of range.");
size_t Size = std::min(Chunk.size(), Data.size() - (size_t)Addr);
std::copy_n(Chunk.begin(), Size, &Data[Addr]);
return Size;
}
private:
std::vector<uint8_t> Data;
addr_t m_start_addr;
};
} // namespace lldb_private
#endif