1 //===---------------------ProcessStructReader.h ------------------*- 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 #ifndef LLDB_TARGET_PROCESSSTRUCTREADER_H 10 #define LLDB_TARGET_PROCESSSTRUCTREADER_H 11 12 #include "lldb/lldb-defines.h" 13 #include "lldb/lldb-types.h" 14 15 #include "lldb/Symbol/CompilerType.h" 16 #include "lldb/Target/Process.h" 17 #include "lldb/Utility/ConstString.h" 18 #include "lldb/Utility/DataBufferHeap.h" 19 #include "lldb/Utility/DataExtractor.h" 20 #include "lldb/Utility/Status.h" 21 22 #include <initializer_list> 23 #include <map> 24 #include <string> 25 26 namespace lldb_private { 27 class ProcessStructReader { 28 protected: 29 struct FieldImpl { 30 CompilerType type; 31 size_t offset; 32 size_t size; 33 }; 34 35 std::map<ConstString, FieldImpl> m_fields; 36 DataExtractor m_data; 37 lldb::ByteOrder m_byte_order; 38 size_t m_addr_byte_size; 39 40 public: ProcessStructReader(Process * process,lldb::addr_t base_addr,CompilerType struct_type)41 ProcessStructReader(Process *process, lldb::addr_t base_addr, 42 CompilerType struct_type) 43 : m_byte_order(lldb::eByteOrderInvalid), m_addr_byte_size(0) { 44 if (!process) 45 return; 46 if (base_addr == 0 || base_addr == LLDB_INVALID_ADDRESS) 47 return; 48 m_byte_order = process->GetByteOrder(); 49 m_addr_byte_size = process->GetAddressByteSize(); 50 51 for (size_t idx = 0; idx < struct_type.GetNumFields(); idx++) { 52 std::string name; 53 uint64_t bit_offset; 54 uint32_t bitfield_bit_size; 55 bool is_bitfield; 56 CompilerType field_type = struct_type.GetFieldAtIndex( 57 idx, name, &bit_offset, &bitfield_bit_size, &is_bitfield); 58 // no support for bitfields in here (yet) 59 if (is_bitfield) 60 return; 61 auto size = field_type.GetByteSize(nullptr); 62 // no support for things larger than a uint64_t (yet) 63 if (!size || *size > 8) 64 return; 65 ConstString const_name = ConstString(name.c_str()); 66 size_t byte_index = static_cast<size_t>(bit_offset / 8); 67 m_fields[const_name] = 68 FieldImpl{field_type, byte_index, static_cast<size_t>(*size)}; 69 } 70 auto total_size = struct_type.GetByteSize(nullptr); 71 if (!total_size) 72 return; 73 lldb::WritableDataBufferSP buffer_sp(new DataBufferHeap(*total_size, 0)); 74 Status error; 75 process->ReadMemoryFromInferior(base_addr, buffer_sp->GetBytes(), 76 *total_size, error); 77 if (error.Fail()) 78 return; 79 m_data = DataExtractor(buffer_sp, m_byte_order, m_addr_byte_size); 80 } 81 82 template <typename RetType> 83 RetType GetField(ConstString name, RetType fail_value = RetType()) { 84 auto iter = m_fields.find(name), end = m_fields.end(); 85 if (iter == end) 86 return fail_value; 87 auto size = iter->second.size; 88 if (sizeof(RetType) < size) 89 return fail_value; 90 lldb::offset_t offset = iter->second.offset; 91 if (offset + size > m_data.GetByteSize()) 92 return fail_value; 93 return (RetType)(m_data.GetMaxU64(&offset, size)); 94 } 95 96 size_t GetOffsetOf(ConstString name, size_t fail_value = SIZE_MAX) { 97 auto iter = m_fields.find(name), end = m_fields.end(); 98 if (iter == end) 99 return fail_value; 100 return iter->second.offset; 101 } 102 }; 103 } 104 105 #endif // LLDB_TARGET_PROCESSSTRUCTREADER_H 106