src/common/linux/scoped_tmpfile.h

// Copyright 2022 Google LLC
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// Utility class for creating a temporary file for that is deleted in the
// destructor.

#ifndef COMMON_LINUX_SCOPED_TMPFILE_H_
#define COMMON_LINUX_SCOPED_TMPFILE_H_

#include <string>

namespace google_breakpad {

// Small RAII wrapper for temporary files.
//
// Example:
//   ScopedTmpFile tmp;
//   if (tmp.Init("Some file contents")) {
//     ...
//   }
class ScopedTmpFile {
 public:
  // Initialize the ScopedTmpFile object - this does not create the temporary
  // file until Init is called.
  ScopedTmpFile();

  // Destroy temporary file on scope exit.
  ~ScopedTmpFile();

  // Creates the empty temporary file - returns true iff the temporary file was
  // created successfully. Should always be checked before using the file.
  bool InitEmpty();

  // Creates the temporary file with the provided C string. The terminating null
  // is not written. Returns true iff the temporary file was created
  // successfully and the contents were written successfully.
  bool InitString(const char* text);

  // Creates the temporary file with the provided data. Returns true iff the
  // temporary file was created successfully and the contents were written
  // successfully.
  bool InitData(const void* data, size_t data_len);

  // Returns the Posix file descriptor for the test file, or -1 if Init()
  // returned false. Note: on Windows, this always returns -1.
  int GetFd() const {
    return fd_;
  }

 private:
  // Set the contents of the temporary file, and seek back to the start of the
  // file. On failure, returns false.
  bool SetContents(const void* data, size_t data_len);

  int fd_ = -1;
};

}  // namespace google_breakpad

#endif  // COMMON_LINUX_SCOPED_TMPFILE_H_