1 /*
2  * Copyright (C) 2012 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef ART_COMPILER_ELF_WRITER_H_
18 #define ART_COMPILER_ELF_WRITER_H_
19 
20 #include <stdint.h>
21 #include <cstddef>
22 #include <string>
23 #include <vector>
24 
25 #include "base/macros.h"
26 #include "base/mutex.h"
27 #include "os.h"
28 #include "utils/array_ref.h"
29 
30 namespace art {
31 
32 class ElfFile;
33 class OutputStream;
34 
35 namespace debug {
36 struct MethodDebugInfo;
37 }  // namespace debug
38 
39 class ElfWriter {
40  public:
41   // Looks up information about location of oat file in elf file container.
42   // Used for ImageWriter to perform memory layout.
43   static void GetOatElfInformation(File* file,
44                                    size_t* oat_loaded_size,
45                                    size_t* oat_data_offset);
46 
47   // Returns runtime oat_data runtime address for an opened ElfFile.
48   static uintptr_t GetOatDataAddress(ElfFile* elf_file);
49 
50   static bool Fixup(File* file, uintptr_t oat_data_begin);
51 
~ElfWriter()52   virtual ~ElfWriter() {}
53 
54   virtual void Start() = 0;
55   virtual void SetLoadedSectionSizes(size_t rodata_size, size_t text_size, size_t bss_size) = 0;
56   virtual void PrepareDebugInfo(const ArrayRef<const debug::MethodDebugInfo>& method_infos) = 0;
57   virtual OutputStream* StartRoData() = 0;
58   virtual void EndRoData(OutputStream* rodata) = 0;
59   virtual OutputStream* StartText() = 0;
60   virtual void EndText(OutputStream* text) = 0;
61   virtual void WriteDynamicSection() = 0;
62   virtual void WriteDebugInfo(const ArrayRef<const debug::MethodDebugInfo>& method_infos) = 0;
63   virtual void WritePatchLocations(const ArrayRef<const uintptr_t>& patch_locations) = 0;
64   virtual bool End() = 0;
65 
66   // Get the ELF writer's stream. This stream can be used for writing data directly
67   // to a section after the section has been finished. When that's done, the user
68   // should Seek() back to the position where the stream was before this operation.
69   virtual OutputStream* GetStream() = 0;
70 
71   // Get the size that the loaded ELF file will occupy in memory.
72   virtual size_t GetLoadedSize() = 0;
73 
74  protected:
75   ElfWriter() = default;
76 };
77 
78 }  // namespace art
79 
80 #endif  // ART_COMPILER_ELF_WRITER_H_
81