src/tint/utils/file/tmpfile.h

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#ifndef SRC_TINT_UTILS_FILE_TMPFILE_H_
#define SRC_TINT_UTILS_FILE_TMPFILE_H_

#include <span>
#include <string>

#include "src/tint/utils/text/string_stream.h"

namespace tint {

/// TmpFile constructs a temporary file that can be written to, and is
/// automatically deleted on destruction.
class TmpFile {
  public:
    /// Constructor.
    /// Creates a new temporary file which can be written to.
    /// The temporary file will be automatically deleted on destruction.
    /// @param extension optional file extension to use with the file. The file
    /// have no extension by default.
    explicit TmpFile(std::string extension = "");

    /// Destructor.
    /// Deletes the temporary file.
    ~TmpFile();

    /// @return true if the temporary file was successfully created.
    explicit operator bool() { return !path_.empty(); }

    /// @return the path to the temporary file
    std::string Path() const { return path_; }

    /// Opens the temporary file and appends the raw bytes in |data| to the end
    /// of the temporary file. The temporary file is closed again before
    /// returning, allowing other processes to open the file on operating systems
    /// that require exclusive ownership of opened files.
    /// @param data the data to write to the end of the file
    /// @returns true on success, otherwise false
    bool Append(std::span<const std::byte> data) const;

    /// Appends the argument to the end of the file.
    /// @param data the data to write to the end of the file
    /// @return a reference to this TmpFile
    template <typename T>
    inline TmpFile& operator<<(T&& data) {
        StringStream ss;
        ss << data;
        std::string str = ss.str();
        Append(std::as_bytes(std::span(str)));
        return *this;
    }

  private:
    TmpFile(const TmpFile&) = delete;
    TmpFile& operator=(const TmpFile&) = delete;

    std::string path_;
};

}  // namespace tint

#endif  // SRC_TINT_UTILS_FILE_TMPFILE_H_