//===- llvm/System/Program.h ------------------------------------*- C++ -*-===//
// 
//                     The LLVM Compiler Infrastructure
//
// This file was developed by Reid Spencer and is distributed under the 
// University of Illinois Open Source License. See LICENSE.TXT for details.
// 
//===----------------------------------------------------------------------===//
//
// This file declares the llvm::sys::Program class.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_SYSTEM_PROGRAM_H
#define LLVM_SYSTEM_PROGRAM_H

#include "llvm/System/Path.h"
#include <vector>

namespace llvm {
namespace sys {

  /// This class provides an abstraction for programs that are executable by the
  /// operating system. It derives from Path because every executable on all
  /// known operating systems has a pathname that is needed in order to execute
  /// the program. This class provides an operating system agnostic interface
  /// for the procedure of finding and executing programs in a variety of ways.
  /// @since 1.4
  /// @brief An abstraction for operating system programs.
  class Program : public Path {
    /// @name Constructors
    /// @{
    public:
      /// This static constructor (factory) will attempt to locate a program in
      /// the operating system's file system using some pre-determined set of 
      /// locations to search (e.g. the PATH on Unix). 
      /// @returns A Path object initialized to the path of the program or a
      /// Path object that is empty (invalid) if the program could not be found.
      /// @throws nothing
      /// @brief Construct a Program by finding it by name.
      static Program FindProgramByName(const std::string& name);

      /// This static constructor (factory) constructs a Program object that
      /// refers to the currently executing program. 
      /// @brief Constructs a Program object for the currently executing
      /// program.
      // static Program This();
      /// FIXME: Not sure if this is currently doable.


    /// @}
    /// @name Methods
    /// @{
    public:
      /// This function executes the program using the \p arguments provided and
      /// waits for the program to exit. This function will block the current
      /// program until the invoked program exits. The invoked program will 
      /// inherit the stdin, stdout, and stderr file descriptors, the
      /// environment and other configuration settings of the inoking program.
      /// If Path::executable() does not return true when this function is
      /// called then a std::string is thrown. 
      /// Path::executable() returns true.
      /// @param arguments A vector of strings that are passed to the program.
      /// The first element should *not* be the name of the program.
      /// @returns an integer result code indicating the status of the program.
      /// @throws std::string on a variety of error conditions or if the invoked 
      /// program aborted abnormally.
      /// @brief Executes the program with the given set of \p arguments.
      int ExecuteAndWait(const std::vector<std::string>& arguments) const;
    /// @}
  };
}
}

// vim: sw=2

#endif