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/DataBufferHeap.h"
18#include "lldb/Utility/DataExtractor.h"
19#include "lldb/Utility/Status.h"
20
21#include "llvm/ADT/StringMap.h"
22
23#include <initializer_list>
24#include <map>
25#include <string>
26
27namespace lldb_private {
28class ProcessStructReader {
29protected:
30 struct FieldImpl {
31 CompilerType type;
32 size_t offset;
33 size_t size;
34 };
35
36 llvm::StringMap<FieldImpl> m_fields;
37 DataExtractor m_data;
38 lldb::ByteOrder m_byte_order;
39 size_t m_addr_byte_size;
40
41public:
42 ProcessStructReader(Process *process, lldb::addr_t base_addr,
43 CompilerType struct_type)
44 : m_byte_order(lldb::eByteOrderInvalid), m_addr_byte_size(0) {
45 if (!process)
46 return;
47 if (base_addr == 0 || base_addr == LLDB_INVALID_ADDRESS)
48 return;
49 m_byte_order = process->GetByteOrder();
50 m_addr_byte_size = process->GetAddressByteSize();
51
52 for (size_t idx = 0; idx < struct_type.GetNumFields(); idx++) {
53 std::string name;
54 uint64_t bit_offset;
55 uint32_t bitfield_bit_size;
56 bool is_bitfield;
57 CompilerType field_type = struct_type.GetFieldAtIndex(
58 idx, name, bit_offset_ptr: &bit_offset, bitfield_bit_size_ptr: &bitfield_bit_size, is_bitfield_ptr: &is_bitfield);
59 // no support for bitfields in here (yet)
60 if (is_bitfield)
61 return;
62 auto size = field_type.GetByteSize(exe_scope: nullptr);
63 // no support for things larger than a uint64_t (yet)
64 if (!size || *size > 8)
65 return;
66 size_t byte_index = static_cast<size_t>(bit_offset / 8);
67 m_fields.insert(KV: {name, FieldImpl{.type: field_type, .offset: byte_index,
68 .size: static_cast<size_t>(*size)}});
69 }
70 auto total_size = struct_type.GetByteSize(exe_scope: nullptr);
71 if (!total_size)
72 return;
73 lldb::WritableDataBufferSP buffer_sp(new DataBufferHeap(*total_size, 0));
74 Status error;
75 process->ReadMemoryFromInferior(vm_addr: base_addr, buf: buffer_sp->GetBytes(),
76 size: *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(llvm::StringRef name, RetType fail_value = RetType()) {
84 auto iter = m_fields.find(Key: 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_ptr: &offset, byte_size: size));
94 }
95};
96}
97
98#endif // LLDB_TARGET_PROCESSSTRUCTREADER_H
99

source code of lldb/include/lldb/Target/ProcessStructReader.h