llvm-6502/include/llvm/System/Program.h
2009-08-03 05:02:46 +00:00

149 lines
6.2 KiB
C++

//===- llvm/System/Program.h ------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file 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"
namespace llvm {
namespace sys {
// TODO: Add operations to communicate with the process, redirect its I/O,
// etc.
/// This class provides an abstraction for programs that are executable by the
/// operating system. It provides a platform generic way to find executable
/// programs from the path and to execute them in various ways. The sys::Path
/// class is used to specify the location of the Program.
/// @since 1.4
/// @brief An abstraction for finding and executing programs.
class Program {
/// Opaque handle for target specific data.
void *Data;
unsigned Pid_;
// Noncopyable.
Program(const Program& other);
Program& operator=(const Program& other);
/// @name Methods
/// @{
public:
Program();
~Program();
/// Return process ID of this program.
unsigned GetPid() { return Pid_; }
/// This function executes the program using the \p arguments provided. The
/// invoked program will inherit the stdin, stdout, and stderr file
/// descriptors, the environment and other configuration settings of the
/// invoking program. If Path::executable() does not return true when this
/// function is called then a std::string is thrown.
/// @returns false in case of error, true otherwise.
/// @see FindProgramByName
/// @brief Executes the program with the given set of \p args.
bool Execute
( const Path& path, ///< sys::Path object providing the path of the
///< program to be executed. It is presumed this is the result of
///< the FindProgramByName method.
const char** args, ///< A vector of strings that are passed to the
///< program. The first element should be the name of the program.
///< The list *must* be terminated by a null char* entry.
const char ** env = 0, ///< An optional vector of strings to use for
///< the program's environment. If not provided, the current program's
///< environment will be used.
const sys::Path** redirects = 0, ///< An optional array of pointers to
///< Paths. If the array is null, no redirection is done. The array
///< should have a size of at least three. If the pointer in the array
///< are not null, then the inferior process's stdin(0), stdout(1),
///< and stderr(2) will be redirected to the corresponding Paths.
///< When an empty Path is passed in, the corresponding file
///< descriptor will be disconnected (ie, /dev/null'd) in a portable
///< way.
unsigned memoryLimit = 0, ///< If non-zero, this specifies max. amount
///< of memory can be allocated by process. If memory usage will be
///< higher limit, the child is killed and this call returns. If zero
///< - no memory limit.
std::string* ErrMsg = 0 ///< If non-zero, provides a pointer to a string
///< instance in which error messages will be returned. If the string
///< is non-empty upon return an error occurred while invoking the
///< program.
);
/// This function waits for the program to exit. This function will block
/// the current program until the invoked program exits.
/// @returns an integer result code indicating the status of the program.
/// A zero or positive value indicates the result code of the program. A
/// negative value is the signal number on which it terminated.
/// @see Execute
/// @brief Waits for the program to exit.
int Wait
( unsigned secondsToWait = 0, ///< If non-zero, this specifies the amount
///< of time to wait for the child process to exit. If the time
///< expires, the child is killed and this call returns. If zero,
///< this function will wait until the child finishes or forever if
///< it doesn't.
std::string* ErrMsg = 0 ///< If non-zero, provides a pointer to a string
///< instance in which error messages will be returned. If the string
///< is non-empty upon return an error occurred while invoking the
///< program.
);
/// 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 Path FindProgramByName(const std::string& name);
// These methods change the specified standard stream (stdin or stdout) to
// binary mode. They return true if an error occurred
static bool ChangeStdinToBinary();
static bool ChangeStdoutToBinary();
/// A convenience function equivalent to Program prg; prg.Execute(..);
/// prg.Wait(..);
/// @throws nothing
/// @see Execute, Wait
static int ExecuteAndWait(const Path& path,
const char** args,
const char ** env = 0,
const sys::Path** redirects = 0,
unsigned secondsToWait = 0,
unsigned memoryLimit = 0,
std::string* ErrMsg = 0);
/// A convenience function equivalent to Program prg; prg.Execute(..);
/// @throws nothing
/// @see Execute
static void ExecuteNoWait(const Path& path,
const char** args,
const char ** env = 0,
const sys::Path** redirects = 0,
unsigned memoryLimit = 0,
std::string* ErrMsg = 0);
/// @}
};
}
}
#endif