1//===-- Section.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_CORE_SECTION_H
10#define LLDB_CORE_SECTION_H
11
12#include "lldb/Core/ModuleChild.h"
13#include "lldb/Utility/ConstString.h"
14#include "lldb/Utility/Flags.h"
15#include "lldb/Utility/UserID.h"
16#include "lldb/lldb-defines.h"
17#include "lldb/lldb-enumerations.h"
18#include "lldb/lldb-forward.h"
19#include "lldb/lldb-types.h"
20#include "llvm/Support/JSON.h"
21
22#include <memory>
23#include <vector>
24
25#include <cstddef>
26#include <cstdint>
27
28namespace lldb_private {
29class Address;
30class DataExtractor;
31class ObjectFile;
32class Section;
33class Target;
34
35class SectionList {
36public:
37  typedef std::vector<lldb::SectionSP> collection;
38  typedef collection::iterator iterator;
39  typedef collection::const_iterator const_iterator;
40
41  const_iterator begin() const { return m_sections.begin(); }
42  const_iterator end() const { return m_sections.end(); }
43  const_iterator begin() { return m_sections.begin(); }
44  const_iterator end() { return m_sections.end(); }
45
46  /// Create an empty list.
47  SectionList() = default;
48
49  SectionList &operator=(const SectionList &rhs);
50
51  size_t AddSection(const lldb::SectionSP &section_sp);
52
53  size_t AddUniqueSection(const lldb::SectionSP &section_sp);
54
55  size_t FindSectionIndex(const Section *sect);
56
57  bool ContainsSection(lldb::user_id_t sect_id) const;
58
59  void Dump(llvm::raw_ostream &s, unsigned indent, Target *target,
60            bool show_header, uint32_t depth) const;
61
62  lldb::SectionSP FindSectionByName(ConstString section_dstr) const;
63
64  lldb::SectionSP FindSectionByID(lldb::user_id_t sect_id) const;
65
66  lldb::SectionSP FindSectionByType(lldb::SectionType sect_type,
67                                    bool check_children,
68                                    size_t start_idx = 0) const;
69
70  lldb::SectionSP
71  FindSectionContainingFileAddress(lldb::addr_t addr,
72                                   uint32_t depth = UINT32_MAX) const;
73
74  // Get the number of sections in this list only
75  size_t GetSize() const { return m_sections.size(); }
76
77  // Get the number of sections in this list, and any contained child sections
78  size_t GetNumSections(uint32_t depth) const;
79
80  bool ReplaceSection(lldb::user_id_t sect_id,
81                      const lldb::SectionSP &section_sp,
82                      uint32_t depth = UINT32_MAX);
83
84  // Warning, this can be slow as it's removing items from a std::vector.
85  bool DeleteSection(size_t idx);
86
87  lldb::SectionSP GetSectionAtIndex(size_t idx) const;
88
89  size_t Slide(lldb::addr_t slide_amount, bool slide_children);
90
91  void Clear() { m_sections.clear(); }
92
93  /// Get the debug information size from all sections that contain debug
94  /// information. Symbol tables are not considered part of the debug
95  /// information for this call, just known sections that contain debug
96  /// information.
97  uint64_t GetDebugInfoSize() const;
98
99protected:
100  collection m_sections;
101};
102
103struct JSONSection {
104  std::string name;
105  std::optional<lldb::SectionType> type;
106  std::optional<uint64_t> address;
107  std::optional<uint64_t> size;
108};
109
110class Section : public std::enable_shared_from_this<Section>,
111                public ModuleChild,
112                public UserID,
113                public Flags {
114public:
115  // Create a root section (one that has no parent)
116  Section(const lldb::ModuleSP &module_sp, ObjectFile *obj_file,
117          lldb::user_id_t sect_id, ConstString name,
118          lldb::SectionType sect_type, lldb::addr_t file_vm_addr,
119          lldb::addr_t vm_size, lldb::offset_t file_offset,
120          lldb::offset_t file_size, uint32_t log2align, uint32_t flags,
121          uint32_t target_byte_size = 1);
122
123  // Create a section that is a child of parent_section_sp
124  Section(const lldb::SectionSP &parent_section_sp, // NULL for top level
125                                                    // sections, non-NULL for
126                                                    // child sections
127          const lldb::ModuleSP &module_sp, ObjectFile *obj_file,
128          lldb::user_id_t sect_id, ConstString name,
129          lldb::SectionType sect_type, lldb::addr_t file_vm_addr,
130          lldb::addr_t vm_size, lldb::offset_t file_offset,
131          lldb::offset_t file_size, uint32_t log2align, uint32_t flags,
132          uint32_t target_byte_size = 1);
133
134  ~Section();
135
136  static int Compare(const Section &a, const Section &b);
137
138  bool ContainsFileAddress(lldb::addr_t vm_addr) const;
139
140  SectionList &GetChildren() { return m_children; }
141
142  const SectionList &GetChildren() const { return m_children; }
143
144  void Dump(llvm::raw_ostream &s, unsigned indent, Target *target,
145            uint32_t depth) const;
146
147  void DumpName(llvm::raw_ostream &s) const;
148
149  lldb::addr_t GetLoadBaseAddress(Target *target) const;
150
151  bool ResolveContainedAddress(lldb::addr_t offset, Address &so_addr,
152                               bool allow_section_end = false) const;
153
154  lldb::offset_t GetFileOffset() const { return m_file_offset; }
155
156  void SetFileOffset(lldb::offset_t file_offset) {
157    m_file_offset = file_offset;
158  }
159
160  lldb::offset_t GetFileSize() const { return m_file_size; }
161
162  void SetFileSize(lldb::offset_t file_size) { m_file_size = file_size; }
163
164  lldb::addr_t GetFileAddress() const;
165
166  bool SetFileAddress(lldb::addr_t file_addr);
167
168  lldb::addr_t GetOffset() const;
169
170  lldb::addr_t GetByteSize() const { return m_byte_size; }
171
172  void SetByteSize(lldb::addr_t byte_size) { m_byte_size = byte_size; }
173
174  bool IsFake() const { return m_fake; }
175
176  void SetIsFake(bool fake) { m_fake = fake; }
177
178  bool IsEncrypted() const { return m_encrypted; }
179
180  void SetIsEncrypted(bool b) { m_encrypted = b; }
181
182  bool IsDescendant(const Section *section);
183
184  ConstString GetName() const { return m_name; }
185
186  bool Slide(lldb::addr_t slide_amount, bool slide_children);
187
188  lldb::SectionType GetType() const { return m_type; }
189
190  const char *GetTypeAsCString() const;
191
192  lldb::SectionSP GetParent() const { return m_parent_wp.lock(); }
193
194  bool IsThreadSpecific() const { return m_thread_specific; }
195
196  void SetIsThreadSpecific(bool b) { m_thread_specific = b; }
197
198  /// Get the permissions as OR'ed bits from lldb::Permissions
199  uint32_t GetPermissions() const;
200
201  /// Set the permissions using bits OR'ed from lldb::Permissions
202  void SetPermissions(uint32_t permissions);
203
204  ObjectFile *GetObjectFile() { return m_obj_file; }
205  const ObjectFile *GetObjectFile() const { return m_obj_file; }
206
207  /// Read the section data from the object file that the section
208  /// resides in.
209  ///
210  /// \param[in] dst
211  ///     Where to place the data
212  ///
213  /// \param[in] dst_len
214  ///     How many bytes of section data to read
215  ///
216  /// \param[in] offset
217  ///     The offset in bytes within this section's data at which to
218  ///     start copying data from.
219  ///
220  /// \return
221  ///     The number of bytes read from the section, or zero if the
222  ///     section has no data or \a offset is not a valid offset
223  ///     in this section.
224  lldb::offset_t GetSectionData(void *dst, lldb::offset_t dst_len,
225                                lldb::offset_t offset = 0);
226
227  /// Get the shared reference to the section data from the object
228  /// file that the section resides in. No copies of the data will be
229  /// make unless the object file has been read from memory. If the
230  /// object file is on disk, it will shared the mmap data for the
231  /// entire object file.
232  ///
233  /// \param[in] data
234  ///     Where to place the data, address byte size, and byte order
235  ///
236  /// \return
237  ///     The number of bytes read from the section, or zero if the
238  ///     section has no data or \a offset is not a valid offset
239  ///     in this section.
240  lldb::offset_t GetSectionData(DataExtractor &data);
241
242  uint32_t GetLog2Align() { return m_log2align; }
243
244  void SetLog2Align(uint32_t align) { m_log2align = align; }
245
246  // Get the number of host bytes required to hold a target byte
247  uint32_t GetTargetByteSize() const { return m_target_byte_size; }
248
249  bool IsRelocated() const { return m_relocated; }
250
251  void SetIsRelocated(bool b) { m_relocated = b; }
252
253  /// Returns true if this section contains debug information. Symbol tables
254  /// are not considered debug information since some symbols might contain
255  /// debug information (STABS, COFF) but not all symbols do, so to keep this
256  /// fast and simple only sections that contains only debug information should
257  /// return true.
258  bool ContainsOnlyDebugInfo() const;
259
260protected:
261  ObjectFile *m_obj_file;   // The object file that data for this section should
262                            // be read from
263  lldb::SectionType m_type; // The type of this section
264  lldb::SectionWP m_parent_wp; // Weak pointer to parent section
265  ConstString m_name;          // Name of this section
266  lldb::addr_t m_file_addr; // The absolute file virtual address range of this
267                            // section if m_parent == NULL,
268  // offset from parent file virtual address if m_parent != NULL
269  lldb::addr_t m_byte_size; // Size in bytes that this section will occupy in
270                            // memory at runtime
271  lldb::offset_t m_file_offset; // Object file offset (if any)
272  lldb::offset_t m_file_size;   // Object file size (can be smaller than
273                                // m_byte_size for zero filled sections...)
274  uint32_t m_log2align;   // log_2(align) of the section (i.e. section has to be
275                          // aligned to 2^m_log2align)
276  SectionList m_children; // Child sections
277  bool m_fake : 1, // If true, then this section only can contain the address if
278                   // one of its
279      // children contains an address. This allows for gaps between the
280      // children that are contained in the address range for this section, but
281      // do not produce hits unless the children contain the address.
282      m_encrypted : 1,         // Set to true if the contents are encrypted
283      m_thread_specific : 1,   // This section is thread specific
284      m_readable : 1,          // If this section has read permissions
285      m_writable : 1,          // If this section has write permissions
286      m_executable : 1,        // If this section has executable permissions
287      m_relocated : 1;         // If this section has had relocations applied
288  uint32_t m_target_byte_size; // Some architectures have non-8-bit byte size.
289                               // This is specified as
290                               // as a multiple number of a host bytes
291private:
292  Section(const Section &) = delete;
293  const Section &operator=(const Section &) = delete;
294};
295
296} // namespace lldb_private
297
298namespace llvm {
299namespace json {
300
301bool fromJSON(const llvm::json::Value &value,
302              lldb_private::JSONSection &section, llvm::json::Path path);
303
304bool fromJSON(const llvm::json::Value &value, lldb::SectionType &type,
305              llvm::json::Path path);
306
307} // namespace json
308} // namespace llvm
309
310#endif // LLDB_CORE_SECTION_H
311