1 //===-- NativeRegisterContextLinux.cpp --------------------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "NativeRegisterContextLinux.h" 10 11 #include "lldb/Host/common/NativeProcessProtocol.h" 12 #include "lldb/Host/common/NativeThreadProtocol.h" 13 #include "lldb/Host/linux/Ptrace.h" 14 #include "lldb/Utility/RegisterValue.h" 15 16 #include "Plugins/Process/Linux/NativeProcessLinux.h" 17 #include "Plugins/Process/POSIX/ProcessPOSIXLog.h" 18 19 using namespace lldb_private; 20 using namespace lldb_private::process_linux; 21 22 NativeRegisterContextLinux::NativeRegisterContextLinux( 23 NativeThreadProtocol &native_thread, 24 RegisterInfoInterface *reg_info_interface_p) 25 : NativeRegisterContextRegisterInfo(native_thread, reg_info_interface_p) {} 26 27 lldb::ByteOrder NativeRegisterContextLinux::GetByteOrder() const { 28 return m_thread.GetProcess().GetByteOrder(); 29 } 30 31 Status NativeRegisterContextLinux::ReadRegisterRaw(uint32_t reg_index, 32 RegisterValue ®_value) { 33 const RegisterInfo *const reg_info = GetRegisterInfoAtIndex(reg_index); 34 if (!reg_info) 35 return Status("register %" PRIu32 " not found", reg_index); 36 37 return DoReadRegisterValue(reg_info->byte_offset, reg_info->name, 38 reg_info->byte_size, reg_value); 39 } 40 41 Status 42 NativeRegisterContextLinux::WriteRegisterRaw(uint32_t reg_index, 43 const RegisterValue ®_value) { 44 uint32_t reg_to_write = reg_index; 45 RegisterValue value_to_write = reg_value; 46 47 // Check if this is a subregister of a full register. 48 const RegisterInfo *reg_info = GetRegisterInfoAtIndex(reg_index); 49 if (reg_info->invalidate_regs && 50 (reg_info->invalidate_regs[0] != LLDB_INVALID_REGNUM)) { 51 Status error; 52 53 RegisterValue full_value; 54 uint32_t full_reg = reg_info->invalidate_regs[0]; 55 const RegisterInfo *full_reg_info = GetRegisterInfoAtIndex(full_reg); 56 57 // Read the full register. 58 error = ReadRegister(full_reg_info, full_value); 59 if (error.Fail()) 60 return error; 61 62 lldb::ByteOrder byte_order = GetByteOrder(); 63 uint8_t dst[RegisterValue::kMaxRegisterByteSize]; 64 65 // Get the bytes for the full register. 66 const uint32_t dest_size = full_value.GetAsMemoryData( 67 full_reg_info, dst, sizeof(dst), byte_order, error); 68 if (error.Success() && dest_size) { 69 uint8_t src[RegisterValue::kMaxRegisterByteSize]; 70 71 // Get the bytes for the source data. 72 const uint32_t src_size = reg_value.GetAsMemoryData( 73 reg_info, src, sizeof(src), byte_order, error); 74 if (error.Success() && src_size && (src_size < dest_size)) { 75 // Copy the src bytes to the destination. 76 memcpy(dst + (reg_info->byte_offset & 0x1), src, src_size); 77 // Set this full register as the value to write. 78 value_to_write.SetBytes(dst, full_value.GetByteSize(), byte_order); 79 value_to_write.SetType(full_reg_info); 80 reg_to_write = full_reg; 81 } 82 } 83 } 84 85 const RegisterInfo *const register_to_write_info_p = 86 GetRegisterInfoAtIndex(reg_to_write); 87 assert(register_to_write_info_p && 88 "register to write does not have valid RegisterInfo"); 89 if (!register_to_write_info_p) 90 return Status("NativeRegisterContextLinux::%s failed to get RegisterInfo " 91 "for write register index %" PRIu32, 92 __FUNCTION__, reg_to_write); 93 94 return DoWriteRegisterValue(reg_info->byte_offset, reg_info->name, reg_value); 95 } 96 97 Status NativeRegisterContextLinux::ReadGPR() { 98 return NativeProcessLinux::PtraceWrapper( 99 PTRACE_GETREGS, m_thread.GetID(), nullptr, GetGPRBuffer(), GetGPRSize()); 100 } 101 102 Status NativeRegisterContextLinux::WriteGPR() { 103 return NativeProcessLinux::PtraceWrapper( 104 PTRACE_SETREGS, m_thread.GetID(), nullptr, GetGPRBuffer(), GetGPRSize()); 105 } 106 107 Status NativeRegisterContextLinux::ReadFPR() { 108 return NativeProcessLinux::PtraceWrapper(PTRACE_GETFPREGS, m_thread.GetID(), 109 nullptr, GetFPRBuffer(), 110 GetFPRSize()); 111 } 112 113 Status NativeRegisterContextLinux::WriteFPR() { 114 return NativeProcessLinux::PtraceWrapper(PTRACE_SETFPREGS, m_thread.GetID(), 115 nullptr, GetFPRBuffer(), 116 GetFPRSize()); 117 } 118 119 Status NativeRegisterContextLinux::ReadRegisterSet(void *buf, size_t buf_size, 120 unsigned int regset) { 121 return NativeProcessLinux::PtraceWrapper(PTRACE_GETREGSET, m_thread.GetID(), 122 static_cast<void *>(®set), buf, 123 buf_size); 124 } 125 126 Status NativeRegisterContextLinux::WriteRegisterSet(void *buf, size_t buf_size, 127 unsigned int regset) { 128 return NativeProcessLinux::PtraceWrapper(PTRACE_SETREGSET, m_thread.GetID(), 129 static_cast<void *>(®set), buf, 130 buf_size); 131 } 132 133 Status NativeRegisterContextLinux::DoReadRegisterValue(uint32_t offset, 134 const char *reg_name, 135 uint32_t size, 136 RegisterValue &value) { 137 Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_REGISTERS)); 138 139 long data; 140 Status error = NativeProcessLinux::PtraceWrapper( 141 PTRACE_PEEKUSER, m_thread.GetID(), reinterpret_cast<void *>(offset), 142 nullptr, 0, &data); 143 144 if (error.Success()) 145 // First cast to an unsigned of the same size to avoid sign extension. 146 value.SetUInt(static_cast<unsigned long>(data), size); 147 148 LLDB_LOG(log, "{0}: {1:x}", reg_name, data); 149 return error; 150 } 151 152 Status NativeRegisterContextLinux::DoWriteRegisterValue( 153 uint32_t offset, const char *reg_name, const RegisterValue &value) { 154 Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_REGISTERS)); 155 156 void *buf = reinterpret_cast<void *>(value.GetAsUInt64()); 157 LLDB_LOG(log, "{0}: {1}", reg_name, buf); 158 159 return NativeProcessLinux::PtraceWrapper( 160 PTRACE_POKEUSER, m_thread.GetID(), reinterpret_cast<void *>(offset), buf); 161 } 162