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29 
30 // linux_ptrace_dumper.h: Define the google_breakpad::LinuxPtraceDumper
31 // class, which is derived from google_breakpad::LinuxDumper to extract
32 // information from a crashed process via ptrace.
33 // This class was originally splitted from google_breakpad::LinuxDumper.
34 
35 #ifndef CLIENT_LINUX_MINIDUMP_WRITER_LINUX_PTRACE_DUMPER_H_
36 #define CLIENT_LINUX_MINIDUMP_WRITER_LINUX_PTRACE_DUMPER_H_
37 
38 #include "client/linux/minidump_writer/linux_dumper.h"
39 
40 namespace google_breakpad {
41 
42 class LinuxPtraceDumper : public LinuxDumper {
43  public:
44   // Constructs a dumper for extracting information of a given process
45   // with a process ID of |pid|.
46   explicit LinuxPtraceDumper(pid_t pid);
47 
48   // Implements LinuxDumper::BuildProcPath().
49   // Builds a proc path for a certain pid for a node (/proc/<pid>/<node>).
50   // |path| is a character array of at least NAME_MAX bytes to return the
51   // result. |node| is the final node without any slashes. Returns true on
52   // success.
53   virtual bool BuildProcPath(char* path, pid_t pid, const char* node) const;
54 
55   // Implements LinuxDumper::CopyFromProcess().
56   // Copies content of |length| bytes from a given process |child|,
57   // starting from |src|, into |dest|. This method uses ptrace to extract
58   // the content from the target process. Always returns true.
59   virtual bool CopyFromProcess(void* dest, pid_t child, const void* src,
60                                size_t length);
61 
62   // Implements LinuxDumper::GetThreadInfoByIndex().
63   // Reads information about the |index|-th thread of |threads_|.
64   // Returns true on success. One must have called |ThreadsSuspend| first.
65   virtual bool GetThreadInfoByIndex(size_t index, ThreadInfo* info);
66 
67   // Implements LinuxDumper::IsPostMortem().
68   // Always returns false to indicate this dumper performs a dump of
69   // a crashed process via ptrace.
70   virtual bool IsPostMortem() const;
71 
72   // Implements LinuxDumper::ThreadsSuspend().
73   // Suspends all threads in the given process. Returns true on success.
74   virtual bool ThreadsSuspend();
75 
76   // Implements LinuxDumper::ThreadsResume().
77   // Resumes all threads in the given process. Returns true on success.
78   virtual bool ThreadsResume();
79 
80  protected:
81   // Implements LinuxDumper::EnumerateThreads().
82   // Enumerates all threads of the given process into |threads_|.
83   virtual bool EnumerateThreads();
84 
85  private:
86   // Set to true if all threads of the crashed process are suspended.
87   bool threads_suspended_;
88 
89   // Read the tracee's registers on kernel with PTRACE_GETREGSET support.
90   // Returns false if PTRACE_GETREGSET is not defined.
91   // Returns true on success.
92   bool ReadRegisterSet(ThreadInfo* info, pid_t tid);
93 
94   // Read the tracee's registers on kernel with PTRACE_GETREGS support.
95   // Returns true on success.
96   bool ReadRegisters(ThreadInfo* info, pid_t tid);
97 };
98 
99 }  // namespace google_breakpad
100 
101 #endif  // CLIENT_LINUX_HANDLER_LINUX_PTRACE_DUMPER_H_
102