1  // Copyright 2010 Google LLC
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  9  //     * Redistributions in binary form must reproduce the above
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 15  // this software without specific prior written permission.
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 27  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 28  
 29  #ifndef CLIENT_LINUX_CRASH_GENERATION_CRASH_GENERATION_SERVER_H_
 30  #define CLIENT_LINUX_CRASH_GENERATION_CRASH_GENERATION_SERVER_H_
 31  
 32  #include <pthread.h>
 33  
 34  #include <string>
 35  
 36  #include "common/using_std_string.h"
 37  
 38  namespace google_breakpad {
 39  
 40  class ClientInfo;
 41  
 42  class CrashGenerationServer {
 43  public:
 44    // WARNING: callbacks may be invoked on a different thread
 45    // than that which creates the CrashGenerationServer.  They must
 46    // be thread safe.
 47    typedef void (*OnClientDumpRequestCallback)(void* context,
 48                                                const ClientInfo* client_info,
 49                                                const string* file_path);
 50  
 51    typedef void (*OnClientExitingCallback)(void* context,
 52                                            const ClientInfo* client_info);
 53  
 54    // Create an instance with the given parameters.
 55    //
 56    // Parameter listen_fd: The server fd created by CreateReportChannel().
 57    // Parameter dump_callback: Callback for a client crash dump request.
 58    // Parameter dump_context: Context for client crash dump request callback.
 59    // Parameter exit_callback: Callback for client process exit.
 60    // Parameter exit_context: Context for client exit callback.
 61    // Parameter generate_dumps: Whether to automatically generate dumps.
 62    //     Client code of this class might want to generate dumps explicitly
 63    //     in the crash dump request callback. In that case, false can be
 64    //     passed for this parameter.
 65    // Parameter dump_path: Path for generating dumps; required only if true is
 66    //     passed for generateDumps parameter; NULL can be passed otherwise.
 67    CrashGenerationServer(const int listen_fd,
 68                          OnClientDumpRequestCallback dump_callback,
 69                          void* dump_context,
 70                          OnClientExitingCallback exit_callback,
 71                          void* exit_context,
 72                          bool generate_dumps,
 73                          const string* dump_path);
 74  
 75    ~CrashGenerationServer();
 76  
 77    // Perform initialization steps needed to start listening to clients.
 78    //
 79    // Return true if initialization is successful; false otherwise.
 80    bool Start();
 81  
 82    // Stop the server.
 83    void Stop();
 84  
 85    // Create a "channel" that can be used by clients to report crashes
 86    // to a CrashGenerationServer.  |*server_fd| should be passed to
 87    // this class's constructor, and |*client_fd| should be passed to
 88    // the ExceptionHandler constructor in the client process.
 89    static bool CreateReportChannel(int* server_fd, int* client_fd);
 90  
 91  private:
 92    // Run the server's event loop
 93    void Run();
 94  
 95    // Invoked when an child process (client) event occurs
 96    // Returning true => "keep running", false => "exit loop"
 97    bool ClientEvent(short revents);
 98  
 99    // Invoked when the controlling thread (main) event occurs
100    // Returning true => "keep running", false => "exit loop"
101    bool ControlEvent(short revents);
102  
103    // Return a unique filename at which a minidump can be written
104    bool MakeMinidumpFilename(string& outFilename);
105  
106    // Trampoline to |Run()|
107    static void* ThreadMain(void* arg);
108  
109    int server_fd_;
110  
111    OnClientDumpRequestCallback dump_callback_;
112    void* dump_context_;
113  
114    OnClientExitingCallback exit_callback_;
115    void* exit_context_;
116  
117    bool generate_dumps_;
118  
119    string dump_dir_;
120  
121    bool started_;
122  
123    pthread_t thread_;
124    int control_pipe_in_;
125    int control_pipe_out_;
126  
127    // disable these
128    CrashGenerationServer(const CrashGenerationServer&);
129    CrashGenerationServer& operator=(const CrashGenerationServer&);
130  };
131  
132  } // namespace google_breakpad
133  
134  #endif // CLIENT_LINUX_CRASH_GENERATION_CRASH_GENERATION_SERVER_H_