| //===- llvm/Support/Process.h -----------------------------------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| /// \file |
| /// |
| /// Provides a library for accessing information about this process and other |
| /// processes on the operating system. Also provides means of spawning |
| /// subprocess for commands. The design of this library is modeled after the |
| /// proposed design of the Boost.Process library, and is design specifically to |
| /// follow the style of standard libraries and potentially become a proposal |
| /// for a standard library. |
| /// |
| /// This file declares the llvm::sys::Process class which contains a collection |
| /// of legacy static interfaces for extracting various information about the |
| /// current process. The goal is to migrate users of this API over to the new |
| /// interfaces. |
| /// |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_SUPPORT_PROCESS_H |
| #define LLVM_SUPPORT_PROCESS_H |
| |
| #include "llvm/ADT/ArrayRef.h" |
| #include "llvm/ADT/Optional.h" |
| #include "llvm/Config/llvm-config.h" |
| #include "llvm/Support/Allocator.h" |
| #include "llvm/Support/DataTypes.h" |
| #include "llvm/Support/TimeValue.h" |
| #include <system_error> |
| |
| namespace llvm { |
| class StringRef; |
| |
| namespace sys { |
| |
| class self_process; |
| |
| /// \brief Generic base class which exposes information about an operating |
| /// system process. |
| /// |
| /// This base class is the core interface behind any OS process. It exposes |
| /// methods to query for generic information about a particular process. |
| /// |
| /// Subclasses implement this interface based on the mechanisms available, and |
| /// can optionally expose more interfaces unique to certain process kinds. |
| class process { |
| protected: |
| /// \brief Only specific subclasses of process objects can be destroyed. |
| virtual ~process(); |
| |
| public: |
| /// \brief Operating system specific type to identify a process. |
| /// |
| /// Note that the windows one is defined to 'unsigned long' as this is the |
| /// documented type for DWORD on windows, and we don't want to pull in the |
| /// Windows headers here. |
| #if defined(LLVM_ON_UNIX) |
| typedef pid_t id_type; |
| #elif defined(LLVM_ON_WIN32) |
| typedef unsigned long id_type; // Must match the type of DWORD. |
| #else |
| #error Unsupported operating system. |
| #endif |
| |
| /// \brief Get the operating system specific identifier for this process. |
| virtual id_type get_id() = 0; |
| |
| /// \brief Get the user time consumed by this process. |
| /// |
| /// Note that this is often an approximation and may be zero on platforms |
| /// where we don't have good support for the functionality. |
| virtual TimeValue get_user_time() const = 0; |
| |
| /// \brief Get the system time consumed by this process. |
| /// |
| /// Note that this is often an approximation and may be zero on platforms |
| /// where we don't have good support for the functionality. |
| virtual TimeValue get_system_time() const = 0; |
| |
| /// \brief Get the wall time consumed by this process. |
| /// |
| /// Note that this is often an approximation and may be zero on platforms |
| /// where we don't have good support for the functionality. |
| virtual TimeValue get_wall_time() const = 0; |
| |
| /// \name Static factory routines for processes. |
| /// @{ |
| |
| /// \brief Get the process object for the current process. |
| static self_process *get_self(); |
| |
| /// @} |
| |
| }; |
| |
| /// \brief The specific class representing the current process. |
| /// |
| /// The current process can both specialize the implementation of the routines |
| /// and can expose certain information not available for other OS processes. |
| class self_process : public process { |
| friend class process; |
| |
| /// \brief Private destructor, as users shouldn't create objects of this |
| /// type. |
| virtual ~self_process(); |
| |
| public: |
| id_type get_id() override; |
| TimeValue get_user_time() const override; |
| TimeValue get_system_time() const override; |
| TimeValue get_wall_time() const override; |
| |
| /// \name Process configuration (sysconf on POSIX) |
| /// @{ |
| |
| /// \brief Get the virtual memory page size. |
| /// |
| /// Query the operating system for this process's page size. |
| size_t page_size() const { return PageSize; }; |
| |
| /// @} |
| |
| private: |
| /// \name Cached process state. |
| /// @{ |
| |
| /// \brief Cached page size, this cannot vary during the life of the process. |
| size_t PageSize; |
| |
| /// @} |
| |
| /// \brief Constructor, used by \c process::get_self() only. |
| self_process(); |
| }; |
| |
| |
| /// \brief A collection of legacy interfaces for querying information about the |
| /// current executing process. |
| class Process { |
| public: |
| /// \brief Return process memory usage. |
| /// This static function will return the total amount of memory allocated |
| /// by the process. This only counts the memory allocated via the malloc, |
| /// calloc and realloc functions and includes any "free" holes in the |
| /// allocated space. |
| static size_t GetMallocUsage(); |
| |
| /// This static function will set \p user_time to the amount of CPU time |
| /// spent in user (non-kernel) mode and \p sys_time to the amount of CPU |
| /// time spent in system (kernel) mode. If the operating system does not |
| /// support collection of these metrics, a zero TimeValue will be for both |
| /// values. |
| /// \param elapsed Returns the TimeValue::now() giving current time |
| /// \param user_time Returns the current amount of user time for the process |
| /// \param sys_time Returns the current amount of system time for the process |
| static void GetTimeUsage(TimeValue &elapsed, TimeValue &user_time, |
| TimeValue &sys_time); |
| |
| /// This function makes the necessary calls to the operating system to |
| /// prevent core files or any other kind of large memory dumps that can |
| /// occur when a program fails. |
| /// @brief Prevent core file generation. |
| static void PreventCoreFiles(); |
| |
| // This function returns the environment variable \arg name's value as a UTF-8 |
| // string. \arg Name is assumed to be in UTF-8 encoding too. |
| static Optional<std::string> GetEnv(StringRef name); |
| |
| /// This function searches for an existing file in the list of directories |
| /// in a PATH like environment variable, and returns the first file found, |
| /// according to the order of the entries in the PATH like environment |
| /// variable. |
| static Optional<std::string> FindInEnvPath(const std::string& EnvName, |
| const std::string& FileName); |
| |
| /// This function returns a SmallVector containing the arguments passed from |
| /// the operating system to the program. This function expects to be handed |
| /// the vector passed in from main. |
| static std::error_code |
| GetArgumentVector(SmallVectorImpl<const char *> &Args, |
| ArrayRef<const char *> ArgsFromMain, |
| SpecificBumpPtrAllocator<char> &ArgAllocator); |
| |
| /// This function determines if the standard input is connected directly |
| /// to a user's input (keyboard probably), rather than coming from a file |
| /// or pipe. |
| static bool StandardInIsUserInput(); |
| |
| /// This function determines if the standard output is connected to a |
| /// "tty" or "console" window. That is, the output would be displayed to |
| /// the user rather than being put on a pipe or stored in a file. |
| static bool StandardOutIsDisplayed(); |
| |
| /// This function determines if the standard error is connected to a |
| /// "tty" or "console" window. That is, the output would be displayed to |
| /// the user rather than being put on a pipe or stored in a file. |
| static bool StandardErrIsDisplayed(); |
| |
| /// This function determines if the given file descriptor is connected to |
| /// a "tty" or "console" window. That is, the output would be displayed to |
| /// the user rather than being put on a pipe or stored in a file. |
| static bool FileDescriptorIsDisplayed(int fd); |
| |
| /// This function determines if the given file descriptor is displayd and |
| /// supports colors. |
| static bool FileDescriptorHasColors(int fd); |
| |
| /// This function determines the number of columns in the window |
| /// if standard output is connected to a "tty" or "console" |
| /// window. If standard output is not connected to a tty or |
| /// console, or if the number of columns cannot be determined, |
| /// this routine returns zero. |
| static unsigned StandardOutColumns(); |
| |
| /// This function determines the number of columns in the window |
| /// if standard error is connected to a "tty" or "console" |
| /// window. If standard error is not connected to a tty or |
| /// console, or if the number of columns cannot be determined, |
| /// this routine returns zero. |
| static unsigned StandardErrColumns(); |
| |
| /// This function determines whether the terminal connected to standard |
| /// output supports colors. If standard output is not connected to a |
| /// terminal, this function returns false. |
| static bool StandardOutHasColors(); |
| |
| /// This function determines whether the terminal connected to standard |
| /// error supports colors. If standard error is not connected to a |
| /// terminal, this function returns false. |
| static bool StandardErrHasColors(); |
| |
| /// Enables or disables whether ANSI escape sequences are used to output |
| /// colors. This only has an effect on Windows. |
| /// Note: Setting this option is not thread-safe and should only be done |
| /// during initialization. |
| static void UseANSIEscapeCodes(bool enable); |
| |
| /// Whether changing colors requires the output to be flushed. |
| /// This is needed on systems that don't support escape sequences for |
| /// changing colors. |
| static bool ColorNeedsFlush(); |
| |
| /// This function returns the colorcode escape sequences. |
| /// If ColorNeedsFlush() is true then this function will change the colors |
| /// and return an empty escape sequence. In that case it is the |
| /// responsibility of the client to flush the output stream prior to |
| /// calling this function. |
| static const char *OutputColor(char c, bool bold, bool bg); |
| |
| /// Same as OutputColor, but only enables the bold attribute. |
| static const char *OutputBold(bool bg); |
| |
| /// This function returns the escape sequence to reverse forground and |
| /// background colors. |
| static const char *OutputReverse(); |
| |
| /// Resets the terminals colors, or returns an escape sequence to do so. |
| static const char *ResetColor(); |
| |
| /// Get the result of a process wide random number generator. The |
| /// generator will be automatically seeded in non-deterministic fashion. |
| static unsigned GetRandomNumber(); |
| }; |
| |
| } |
| } |
| |
| #endif |