1 files changed, 118 insertions, 0 deletions
diff --git a/third_party/nix/src/libutil/types.hh b/third_party/nix/src/libutil/types.hh
new file mode 100644
index 0000000000..bf95206d08
--- /dev/null
+++ b/third_party/nix/src/libutil/types.hh
@@ -0,0 +1,118 @@
+#pragma once
+
+#include <boost/format.hpp>
+#include <list>
+#include <map>
+#include <memory>
+#include <set>
+#include <string>
+
+#include "libutil/ref.hh"
+
+/* Before 4.7, gcc's std::exception uses empty throw() specifiers for
+ * its (virtual) destructor and what() in c++11 mode, in violation of spec
+ */
+#ifdef __GNUC__
+#if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 7)
+#define EXCEPTION_NEEDS_THROW_SPEC
+#endif
+#endif
+
+namespace nix {
+
+/* Inherit some names from other namespaces for convenience. */
+using boost::format;
+
+/* A variadic template that does nothing. Useful to call a function
+   for all variadic arguments but ignoring the result. */
+struct nop {
+  template <typename... T>
+  explicit nop(T...) {}
+};
+
+struct FormatOrString {
+  std::string s;
+  FormatOrString(const std::string& s) : s(s){};
+  FormatOrString(const format& f) : s(f.str()){};
+  FormatOrString(const char* s) : s(s){};
+};
+
+/* A helper for formatting strings. ‘fmt(format, a_0, ..., a_n)’ is
+   equivalent to ‘boost::format(format) % a_0 % ... %
+   ... a_n’. However, ‘fmt(s)’ is equivalent to ‘s’ (so no %-expansion
+   takes place). */
+
+inline std::string fmt(const std::string& s) { return s; }
+
+inline std::string fmt(std::string_view s) { return std::string(s); }
+
+inline std::string fmt(const char* s) { return s; }
+
+inline std::string fmt(const FormatOrString& fs) { return fs.s; }
+
+template <typename... Args>
+inline std::string fmt(const std::string& fs, Args... args) {
+  boost::format f(fs);
+  f.exceptions(boost::io::all_error_bits ^ boost::io::too_many_args_bit);
+  nop{boost::io::detail::feed(f, args)...};
+  return f.str();
+}
+
+/* BaseError should generally not be caught, as it has Interrupted as
+   a subclass. Catch Error instead. */
+class BaseError : public std::exception {
+ protected:
+  std::string prefix_;  // used for location traces etc.
+  std::string err;
+
+ public:
+  unsigned int status = 1;  // exit status
+
+  template <typename... Args>
+  explicit BaseError(unsigned int status, Args... args)
+      : err(fmt(args...)), status(status) {}
+
+  template <typename... Args>
+  explicit BaseError(Args... args) : err(fmt(args...)) {}
+
+#ifdef EXCEPTION_NEEDS_THROW_SPEC
+  ~BaseError() noexcept {};
+  const char* what() const noexcept { return err.c_str(); }
+#else
+  const char* what() const noexcept { return err.c_str(); }
+#endif
+
+  const std::string& msg() const { return err; }
+  const std::string& prefix() const { return prefix_; }
+  BaseError& addPrefix(const FormatOrString& fs);
+};
+
+#define MakeError(newClass, superClass) \
+  class newClass : public superClass {  \
+   public:                              \
+    using superClass::superClass;       \
+  };
+
+MakeError(Error, BaseError);
+
+class SysError : public Error {
+ public:
+  int errNo;
+
+  template <typename... Args>
+  explicit SysError(Args... args) : Error(addErrno(fmt(args...))) {}
+
+ private:
+  std::string addErrno(const std::string& s);
+};
+
+typedef std::list<std::string> Strings;
+using StringSet = std::set<std::string>;
+using StringMap = std::map<std::string, std::string>;
+
+/* Paths are just strings. */
+using Path = std::string;
+using Paths = std::list<Path>;
+using PathSet = std::set<Path>;
+
+}  // namespace nix