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29
30// elf_core_dump.h: Define the google_breakpad::ElfCoreDump class, which
31// encapsulates an ELF core dump file mapped into memory.
32
33#ifndef COMMON_LINUX_ELF_CORE_DUMP_H_
34#define COMMON_LINUX_ELF_CORE_DUMP_H_
35
36#include <elf.h>
37#include <limits.h>
38#include <link.h>
39#include <stddef.h>
40
41#include "common/memory_range.h"
42
43namespace google_breakpad {
44
45// A class encapsulating an ELF core dump file mapped into memory, which
46// provides methods for accessing program headers and the note section.
47class ElfCoreDump {
48 public:
49 // ELF types based on the native word size.
50 typedef ElfW(Ehdr) Ehdr;
51 typedef ElfW(Nhdr) Nhdr;
52 typedef ElfW(Phdr) Phdr;
53 typedef ElfW(Word) Word;
54 typedef ElfW(Addr) Addr;
55#if ULONG_MAX == 0xffffffff
56 static const int kClass = ELFCLASS32;
57#elif ULONG_MAX == 0xffffffffffffffff
58 static const int kClass = ELFCLASS64;
59#else
60#error "Unsupported word size for ElfCoreDump."
61#endif
62
63 // A class encapsulating the note content in a core dump, which provides
64 // methods for accessing the name and description of a note.
65 class Note {
66 public:
67 Note();
68
69 // Constructor that takes the note content from |content|.
70 explicit Note(const MemoryRange& content);
71
72 // Returns true if this note is valid, i,e. a note header is found in
73 // |content_|, or false otherwise.
74 bool IsValid() const;
75
76 // Returns the note header, or NULL if no note header is found in
77 // |content_|.
78 const Nhdr* GetHeader() const;
79
80 // Returns the note type, or 0 if no note header is found in |content_|.
81 Word GetType() const;
82
83 // Returns a memory range covering the note name, or an empty range
84 // if no valid note name is found in |content_|.
85 MemoryRange GetName() const;
86
87 // Returns a memory range covering the note description, or an empty
88 // range if no valid note description is found in |content_|.
89 MemoryRange GetDescription() const;
90
91 // Returns the note following this note, or an empty note if no valid
92 // note is found after this note.
93 Note GetNextNote() const;
94
95 private:
96 // Returns the size in bytes round up to the word alignment, specified
97 // for the note section, of a given size in bytes.
98 static size_t AlignedSize(size_t size);
99
100 // Note content.
101 MemoryRange content_;
102 };
103
104 ElfCoreDump();
105
106 // Constructor that takes the core dump content from |content|.
107 explicit ElfCoreDump(const MemoryRange& content);
108
109 ~ElfCoreDump();
110
111 // Sets the core dump content to |content|.
112 void SetContent(const MemoryRange& content);
113
114 // Returns true if a valid ELF header in the core dump, or false otherwise.
115 bool IsValid() const;
116
117 // Returns the ELF header in the core dump, or NULL if no ELF header
118 // is found in |content_|.
119 const Ehdr* GetHeader() const;
120
121 // Returns the |index|-th program header in the core dump, or NULL if no
122 // ELF header is found in |content_| or |index| is out of bounds.
123 const Phdr* GetProgramHeader(unsigned index) const;
124
125 // Returns the first program header of |type| in the core dump, or NULL if
126 // no ELF header is found in |content_| or no program header of |type| is
127 // found.
128 const Phdr* GetFirstProgramHeaderOfType(Word type) const;
129
130 // Returns the number of program headers in the core dump, or 0 if no
131 // ELF header is found in |content_|.
132 unsigned GetProgramHeaderCount() const;
133
134 // Copies |length| bytes of data starting at |virtual_address| in the core
135 // dump to |buffer|. |buffer| should be a valid pointer to a buffer of at
136 // least |length| bytes. Returns true if the data to be copied is found in
137 // the core dump, or false otherwise.
138 bool CopyData(void* buffer, Addr virtual_address, size_t length);
139
140 // Returns the first note found in the note section of the core dump, or
141 // an empty note if no note is found.
142 Note GetFirstNote() const;
143
144 // Sets the mem fd.
145 void SetProcMem(const int fd);
146
147 private:
148 // Core dump content.
149 MemoryRange content_;
150
151 // Descriptor for /proc/<pid>/mem.
152 int proc_mem_fd_;
153};
154
155} // namespace google_breakpad
156
157#endif // COMMON_LINUX_ELF_CORE_DUMP_H_
158