1//===-- ObjectContainer.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_SYMBOL_OBJECTCONTAINER_H
10#define LLDB_SYMBOL_OBJECTCONTAINER_H
11
12#include "lldb/Core/ModuleChild.h"
13#include "lldb/Core/PluginInterface.h"
14#include "lldb/Utility/DataExtractor.h"
15#include "lldb/Utility/Endian.h"
16#include "lldb/Utility/FileSpec.h"
17#include "lldb/lldb-private.h"
18
19namespace lldb_private {
20
21/// \class ObjectContainer ObjectContainer.h "lldb/Symbol/ObjectContainer.h"
22/// A plug-in interface definition class for object containers.
23///
24/// Object containers contain object files from one or more architectures, and
25/// also can contain one or more named objects.
26///
27/// Typical object containers are static libraries (.a files) that contain
28/// multiple named object files, and universal files that contain multiple
29/// architectures.
30class ObjectContainer : public PluginInterface, public ModuleChild {
31public:
32 /// Construct with a parent module, offset, and header data.
33 ///
34 /// Object files belong to modules and a valid module must be supplied upon
35 /// construction. The at an offset within a file for objects that contain
36 /// more than one architecture or object.
37 ObjectContainer(const lldb::ModuleSP &module_sp, const FileSpec *file,
38 lldb::offset_t file_offset, lldb::offset_t length,
39 lldb::DataBufferSP data_sp, lldb::offset_t data_offset);
40
41 /// Destructor.
42 ///
43 /// The destructor is virtual since this class is designed to be inherited
44 /// from by the plug-in instance.
45 ~ObjectContainer() override = default;
46
47 /// Gets the architecture given an index.
48 ///
49 /// Copies the architecture specification for index \a idx.
50 ///
51 /// \param[in] idx
52 /// The architecture index to extract.
53 ///
54 /// \param[out] arch
55 /// A architecture object that will be filled in if \a idx is a
56 /// architecture valid index.
57 ///
58 /// \return
59 /// Returns \b true if \a idx is valid and \a arch has been
60 /// filled in, \b false otherwise.
61 ///
62 /// \see ObjectContainer::GetNumArchitectures() const
63 virtual bool GetArchitectureAtIndex(uint32_t idx, ArchSpec &arch) const {
64 return false;
65 }
66
67 /// Returns the offset into a file at which this object resides.
68 ///
69 /// Some files contain many object files, and this function allows access to
70 /// an object's offset within the file.
71 ///
72 /// \return
73 /// The offset in bytes into the file. Defaults to zero for
74 /// simple object files that a represented by an entire file.
75 virtual lldb::addr_t GetOffset() const { return m_offset; }
76
77 virtual lldb::addr_t GetByteSize() const { return m_length; }
78
79 /// Get the number of objects within this object file (archives).
80 ///
81 /// \return
82 /// Zero for object files that are not archives, or the number
83 /// of objects contained in the archive.
84 virtual size_t GetNumObjects() const { return 0; }
85
86 /// Get the number of architectures in this object file.
87 ///
88 /// The default implementation returns 1 as for object files that contain a
89 /// single architecture. ObjectContainer instances that contain more than
90 /// one architecture should override this function and return an appropriate
91 /// value.
92 ///
93 /// \return
94 /// The number of architectures contained in this object file.
95 virtual size_t GetNumArchitectures() const { return 0; }
96
97 /// Attempts to parse the object header.
98 ///
99 /// This function is used as a test to see if a given plug-in instance can
100 /// parse the header data already contained in ObjectContainer::m_data. If
101 /// an object file parser does not recognize that magic bytes in a header,
102 /// false should be returned and the next plug-in can attempt to parse an
103 /// object file.
104 ///
105 /// \return
106 /// Returns \b true if the header was parsed successfully, \b
107 /// false otherwise.
108 virtual bool ParseHeader() = 0;
109
110 /// Selects an architecture in an object file.
111 ///
112 /// Object files that contain a single architecture should verify that the
113 /// specified \a arch matches the architecture in the object file and return
114 /// \b true or \b false accordingly.
115 ///
116 /// Object files that contain more than one architecture should attempt to
117 /// select that architecture, and if successful, clear out any previous
118 /// state from any previously selected architecture and prepare to return
119 /// information for the new architecture.
120 ///
121 /// \return
122 /// Returns a pointer to the object file of the requested \a
123 /// arch and optional \a name. Returns nullptr of no such object
124 /// file exists in the container.
125 virtual lldb::ObjectFileSP GetObjectFile(const FileSpec *file) = 0;
126
127 static lldb::ObjectContainerSP
128 FindPlugin(const lldb::ModuleSP &module_sp, const lldb::ProcessSP &process_sp,
129 lldb::addr_t header_addr, lldb::WritableDataBufferSP file_data_sp);
130
131protected:
132 /// The file that represents this container objects (which can be different
133 /// from the module's file).
134 FileSpec m_file;
135
136 /// The offset in bytes into the file, or the address in memory
137 lldb::addr_t m_offset;
138
139 /// The size in bytes if known (can be zero).
140 lldb::addr_t m_length;
141
142 /// The data for this object file so things can be parsed lazily.
143 DataExtractor m_data;
144
145private:
146 ObjectContainer(const ObjectContainer &) = delete;
147 const ObjectContainer &operator=(const ObjectContainer &) = delete;
148};
149
150} // namespace lldb_private
151
152#endif // LLDB_SYMBOL_OBJECTCONTAINER_H
153

source code of lldb/include/lldb/Symbol/ObjectContainer.h