google-breakpad/src/client/linux/handler/minidump_descriptor.h

// Copyright (c) 2012 Google Inc.
// All rights reserved.
//
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// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
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//
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#ifndef CLIENT_LINUX_HANDLER_MINIDUMP_DESCRIPTOR_H_
#define CLIENT_LINUX_HANDLER_MINIDUMP_DESCRIPTOR_H_

#include <assert.h>
#include <sys/types.h>

#include <string>

#include "common/using_std_string.h"

// This class describes how a crash dump should be generated, either:
// - Writing a full minidump to a file in a given directory (the actual path,
//   inside the directory, is determined by this class).
// - Writing a full minidump to a given fd.
// - Writing a reduced microdump to the console (logcat on Android).
namespace google_breakpad {

class MinidumpDescriptor {
 public:
  struct MicrodumpOnConsole {};
  static const MicrodumpOnConsole kMicrodumpOnConsole;

  MinidumpDescriptor() : mode_(kUninitialized),
                         fd_(-1),
                         size_limit_(-1) {}

  explicit MinidumpDescriptor(const string& directory)
      : mode_(kWriteMinidumpToFile),
        fd_(-1),
        directory_(directory),
        c_path_(NULL),
        size_limit_(-1) {
    assert(!directory.empty());
  }

  explicit MinidumpDescriptor(int fd)
      : mode_(kWriteMinidumpToFd),
        fd_(fd),
        c_path_(NULL),
        size_limit_(-1) {
    assert(fd != -1);
  }

  explicit MinidumpDescriptor(const MicrodumpOnConsole&)
      : mode_(kWriteMicrodumpToConsole),
        fd_(-1),
        size_limit_(-1) {}

  explicit MinidumpDescriptor(const MinidumpDescriptor& descriptor);
  MinidumpDescriptor& operator=(const MinidumpDescriptor& descriptor);

  static MinidumpDescriptor getMicrodumpDescriptor();

  bool IsFD() const { return mode_ == kWriteMinidumpToFd; }

  int fd() const { return fd_; }

  string directory() const { return directory_; }

  const char* path() const { return c_path_; }

  bool IsMicrodumpOnConsole() const {
    return mode_ == kWriteMicrodumpToConsole;
  }

  // Updates the path so it is unique.
  // Should be called from a normal context: this methods uses the heap.
  void UpdatePath();

  off_t size_limit() const { return size_limit_; }
  void set_size_limit(off_t limit) { size_limit_ = limit; }

 private:
  enum DumpMode {
    kUninitialized = 0,
    kWriteMinidumpToFile,
    kWriteMinidumpToFd,
    kWriteMicrodumpToConsole
  };

  // Specifies the dump mode (see DumpMode).
  DumpMode mode_;

  // The file descriptor where the minidump is generated.
  int fd_;

  // The directory where the minidump should be generated.
  string directory_;
  // The full path to the generated minidump.
  string path_;
  // The C string of |path_|. Precomputed so it can be access from a compromised
  // context.
  const char* c_path_;

  off_t size_limit_;
};

}  // namespace google_breakpad

#endif  // CLIENT_LINUX_HANDLER_MINIDUMP_DESCRIPTOR_H_