include/llvm/Support/Program.h - llvm-project/llvm - Git at Google

 //===- llvm/Support/Program.h ------------------------------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 // This file declares the llvm::sys::Program class.
 //
 //===----------------------------------------------------------------------===//

 #ifndef LLVM_SUPPORT_PROGRAM_H
 #define LLVM_SUPPORT_PROGRAM_H

 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/BitVector.h"
 #include "llvm/ADT/Optional.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Config/llvm-config.h"
 #include "llvm/Support/ErrorOr.h"
 #include "llvm/Support/FileSystem.h"
 #include <chrono>
 #include <system_error>

 namespace llvm {
 namespace sys {

   /// This is the OS-specific separator for PATH like environment variables:
   // a colon on Unix or a semicolon on Windows.
 #if defined(LLVM_ON_UNIX)
   const char EnvPathSeparator = ':';
 #elif defined (_WIN32)
   const char EnvPathSeparator = ';';
 #endif

 #if defined(_WIN32)
   typedef unsigned long procid_t; // Must match the type of DWORD on Windows.
   typedef void *process_t;        // Must match the type of HANDLE on Windows.
 #else
   typedef ::pid_t procid_t;
   typedef procid_t process_t;
 #endif

   /// This struct encapsulates information about a process.
   struct ProcessInfo {
     enum : procid_t { InvalidPid = 0 };

     procid_t Pid;      /// The process identifier.
     process_t Process; /// Platform-dependent process object.

     /// The return code, set after execution.
     int ReturnCode;

     ProcessInfo();
   };

   /// This struct encapsulates information about a process execution.
   struct ProcessStatistics {
     std::chrono::microseconds TotalTime;
     std::chrono::microseconds UserTime;
     uint64_t PeakMemory = 0; ///< Maximum resident set size in KiB.
   };

   /// Find the first executable file \p Name in \p Paths.
   ///
   /// This does not perform hashing as a shell would but instead stats each PATH
   /// entry individually so should generally be avoided. Core LLVM library
   /// functions and options should instead require fully specified paths.
   ///
   /// \param Name name of the executable to find. If it contains any system
   ///   slashes, it will be returned as is.
   /// \param Paths optional list of paths to search for \p Name. If empty it
   ///   will use the system PATH environment instead.
   ///
   /// \returns The fully qualified path to the first \p Name in \p Paths if it
   ///   exists. \p Name if \p Name has slashes in it. Otherwise an error.
   ErrorOr<std::string>
   findProgramByName(StringRef Name, ArrayRef<StringRef> Paths = {});

   // These functions change the specified standard stream (stdin or stdout) mode
   // based on the Flags. They return errc::success if the specified stream was
   // changed. Otherwise, a platform dependent error is returned.
   std::error_code ChangeStdinMode(fs::OpenFlags Flags);
   std::error_code ChangeStdoutMode(fs::OpenFlags Flags);

   // These functions change the specified standard stream (stdin or stdout) to
   // binary mode. They return errc::success if the specified stream
   // was changed. Otherwise a platform dependent error is returned.
   std::error_code ChangeStdinToBinary();
   std::error_code ChangeStdoutToBinary();

   /// This function executes the program using the arguments provided.  The
   /// invoked program will inherit the stdin, stdout, and stderr file
   /// descriptors, the environment and other configuration settings of the
   /// invoking program.
   /// This function waits for the program to finish, so should be avoided in
   /// library functions that aren't expected to block. Consider using
   /// ExecuteNoWait() instead.
   /// \returns an integer result code indicating the status of the program.
   /// A zero or positive value indicates the result code of the program.
   /// -1 indicates failure to execute
   /// -2 indicates a crash during execution or timeout
   int ExecuteAndWait(
       StringRef Program, ///< Path of the program to be executed. It is
       ///< presumed this is the result of the findProgramByName method.
       ArrayRef<StringRef> Args, ///< An array of strings that are passed to the
       ///< program.  The first element should be the name of the program.
       ///< The array should **not** be terminated by an empty StringRef.
       Optional<ArrayRef<StringRef>> Env = None, ///< An optional vector of
       ///< strings to use for the program's environment. If not provided, the
       ///< current program's environment will be used.  If specified, the
       ///< vector should **not** be terminated by an empty StringRef.
       ArrayRef<Optional<StringRef>> Redirects = {}, ///<
       ///< An array of optional paths. Should have a size of zero or three.
       ///< If the array is empty, no redirections are performed.
       ///< Otherwise, the inferior process's stdin(0), stdout(1), and stderr(2)
       ///< will be redirected to the corresponding paths, if the optional path
       ///< is present (not \c llvm::None).
       ///< When an empty path is passed in, the corresponding file descriptor
       ///< will be disconnected (ie, /dev/null'd) in a portable way.
       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.
       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 = nullptr, ///< 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.
       bool *ExecutionFailed = nullptr,
       Optional<ProcessStatistics> *ProcStat = nullptr, ///< If non-zero,
       /// provides a pointer to a structure in which process execution
       /// statistics will be stored.
       BitVector *AffinityMask = nullptr ///< CPUs or processors the new
                                         /// program shall run on.
   );

   /// Similar to ExecuteAndWait, but returns immediately.
   /// @returns The \see ProcessInfo of the newly launched process.
   /// \note On Microsoft Windows systems, users will need to either call
   /// \see Wait until the process finished execution or win32 CloseHandle() API
   /// on ProcessInfo.ProcessHandle to avoid memory leaks.
   ProcessInfo ExecuteNoWait(StringRef Program, ArrayRef<StringRef> Args,
                             Optional<ArrayRef<StringRef>> Env,
                             ArrayRef<Optional<StringRef>> Redirects = {},
                             unsigned MemoryLimit = 0,
                             std::string *ErrMsg = nullptr,
                             bool *ExecutionFailed = nullptr,
                             BitVector *AffinityMask = nullptr);

   /// Return true if the given arguments fit within system-specific
   /// argument length limits.
   bool commandLineFitsWithinSystemLimits(StringRef Program,
                                          ArrayRef<StringRef> Args);

   /// Return true if the given arguments fit within system-specific
   /// argument length limits.
   bool commandLineFitsWithinSystemLimits(StringRef Program,
                                          ArrayRef<const char *> Args);

   /// File encoding options when writing contents that a non-UTF8 tool will
   /// read (on Windows systems). For UNIX, we always use UTF-8.
   enum WindowsEncodingMethod {
     /// UTF-8 is the LLVM native encoding, being the same as "do not perform
     /// encoding conversion".
     WEM_UTF8,
     WEM_CurrentCodePage,
     WEM_UTF16
   };

   /// Saves the UTF8-encoded \p contents string into the file \p FileName
   /// using a specific encoding.
   ///
   /// This write file function adds the possibility to choose which encoding
   /// to use when writing a text file. On Windows, this is important when
   /// writing files with internationalization support with an encoding that is
   /// different from the one used in LLVM (UTF-8). We use this when writing
   /// response files, since GCC tools on MinGW only understand legacy code
   /// pages, and VisualStudio tools only understand UTF-16.
   /// For UNIX, using different encodings is silently ignored, since all tools
   /// work well with UTF-8.
   /// This function assumes that you only use UTF-8 *text* data and will convert
   /// it to your desired encoding before writing to the file.
   ///
   /// FIXME: We use EM_CurrentCodePage to write response files for GNU tools in
   /// a MinGW/MinGW-w64 environment, which has serious flaws but currently is
   /// our best shot to make gcc/ld understand international characters. This
   /// should be changed as soon as binutils fix this to support UTF16 on mingw.
   ///
   /// \returns non-zero error_code if failed
   std::error_code
   writeFileWithEncoding(StringRef FileName, StringRef Contents,
                         WindowsEncodingMethod Encoding = WEM_UTF8);

   /// This function waits for the process specified by \p PI to finish.
   /// \returns A \see ProcessInfo struct with Pid set to:
   /// \li The process id of the child process if the child process has changed
   /// state.
   /// \li 0 if the child process has not changed state.
   /// \note Users of this function should always check the ReturnCode member of
   /// the \see ProcessInfo returned from this function.
   ProcessInfo Wait(
       const ProcessInfo &PI,  ///< The child process that should be waited on.
       unsigned SecondsToWait, ///< 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 function returns. If zero, this function
       ///< will perform a non-blocking wait on the child process.
       bool WaitUntilTerminates, ///< If true, ignores \p SecondsToWait and waits
       ///< until child has terminated.
       std::string *ErrMsg = nullptr, ///< 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.
       Optional<ProcessStatistics> *ProcStat = nullptr ///< If non-zero, provides
       /// a pointer to a structure in which process execution statistics will be
       /// stored.
   );

   /// Print a command argument, and optionally quote it.
   void printArg(llvm::raw_ostream &OS, StringRef Arg, bool Quote);

 #if defined(_WIN32)
   /// Given a list of command line arguments, quote and escape them as necessary
   /// to build a single flat command line appropriate for calling CreateProcess
   /// on
   /// Windows.
   ErrorOr<std::wstring> flattenWindowsCommandLine(ArrayRef<StringRef> Args);
 #endif
   }
 }

 #endif
	//===- llvm/Support/Program.h ------------------------------------- C++ --===//
	//
	// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
	// See https://llvm.org/LICENSE.txt for license information.
	// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
	//
	//===----------------------------------------------------------------------===//
	//
	// This file declares the llvm::sys::Program class.
	//
	//===----------------------------------------------------------------------===//

	#ifndef LLVM_SUPPORT_PROGRAM_H
	#define LLVM_SUPPORT_PROGRAM_H

	#include "llvm/ADT/ArrayRef.h"
	#include "llvm/ADT/BitVector.h"
	#include "llvm/ADT/Optional.h"
	#include "llvm/ADT/StringRef.h"
	#include "llvm/Config/llvm-config.h"
	#include "llvm/Support/ErrorOr.h"
	#include "llvm/Support/FileSystem.h"
	#include <chrono>
	#include <system_error>

	namespace llvm {
	namespace sys {

	/// This is the OS-specific separator for PATH like environment variables:
	// a colon on Unix or a semicolon on Windows.
	#if defined(LLVM_ON_UNIX)
	const char EnvPathSeparator = ':';
	#elif defined (_WIN32)
	const char EnvPathSeparator = ';';
	#endif

	#if defined(_WIN32)
	typedef unsigned long procid_t; // Must match the type of DWORD on Windows.
	typedef void *process_t; // Must match the type of HANDLE on Windows.
	#else
	typedef ::pid_t procid_t;
	typedef procid_t process_t;
	#endif

	/// This struct encapsulates information about a process.
	struct ProcessInfo {
	enum : procid_t { InvalidPid = 0 };

	procid_t Pid; /// The process identifier.
	process_t Process; /// Platform-dependent process object.

	/// The return code, set after execution.
	int ReturnCode;

	ProcessInfo();
	};

	/// This struct encapsulates information about a process execution.
	struct ProcessStatistics {
	std::chrono::microseconds TotalTime;
	std::chrono::microseconds UserTime;
	uint64_t PeakMemory = 0; ///< Maximum resident set size in KiB.
	};

	/// Find the first executable file \p Name in \p Paths.
	///
	/// This does not perform hashing as a shell would but instead stats each PATH
	/// entry individually so should generally be avoided. Core LLVM library
	/// functions and options should instead require fully specified paths.
	///
	/// \param Name name of the executable to find. If it contains any system
	/// slashes, it will be returned as is.
	/// \param Paths optional list of paths to search for \p Name. If empty it
	/// will use the system PATH environment instead.
	///
	/// \returns The fully qualified path to the first \p Name in \p Paths if it
	/// exists. \p Name if \p Name has slashes in it. Otherwise an error.
	ErrorOr<std::string>
	findProgramByName(StringRef Name, ArrayRef<StringRef> Paths = {});

	// These functions change the specified standard stream (stdin or stdout) mode
	// based on the Flags. They return errc::success if the specified stream was
	// changed. Otherwise, a platform dependent error is returned.
	std::error_code ChangeStdinMode(fs::OpenFlags Flags);
	std::error_code ChangeStdoutMode(fs::OpenFlags Flags);

	// These functions change the specified standard stream (stdin or stdout) to
	// binary mode. They return errc::success if the specified stream
	// was changed. Otherwise a platform dependent error is returned.
	std::error_code ChangeStdinToBinary();
	std::error_code ChangeStdoutToBinary();

	/// This function executes the program using the arguments provided. The
	/// invoked program will inherit the stdin, stdout, and stderr file
	/// descriptors, the environment and other configuration settings of the
	/// invoking program.
	/// This function waits for the program to finish, so should be avoided in
	/// library functions that aren't expected to block. Consider using
	/// ExecuteNoWait() instead.
	/// \returns an integer result code indicating the status of the program.
	/// A zero or positive value indicates the result code of the program.
	/// -1 indicates failure to execute
	/// -2 indicates a crash during execution or timeout
	int ExecuteAndWait(
	StringRef Program, ///< Path of the program to be executed. It is
	///< presumed this is the result of the findProgramByName method.
	ArrayRef<StringRef> Args, ///< An array of strings that are passed to the
	///< program. The first element should be the name of the program.
	///< The array should not be terminated by an empty StringRef.
	Optional<ArrayRef<StringRef>> Env = None, ///< An optional vector of
	///< strings to use for the program's environment. If not provided, the
	///< current program's environment will be used. If specified, the
	///< vector should not be terminated by an empty StringRef.
	ArrayRef<Optional<StringRef>> Redirects = {}, ///<
	///< An array of optional paths. Should have a size of zero or three.
	///< If the array is empty, no redirections are performed.
	///< Otherwise, the inferior process's stdin(0), stdout(1), and stderr(2)
	///< will be redirected to the corresponding paths, if the optional path
	///< is present (not \c llvm::None).
	///< When an empty path is passed in, the corresponding file descriptor
	///< will be disconnected (ie, /dev/null'd) in a portable way.
	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.
	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 = nullptr, ///< 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.
	bool *ExecutionFailed = nullptr,
	Optional<ProcessStatistics> *ProcStat = nullptr, ///< If non-zero,
	/// provides a pointer to a structure in which process execution
	/// statistics will be stored.
	BitVector *AffinityMask = nullptr ///< CPUs or processors the new
	/// program shall run on.
	);

	/// Similar to ExecuteAndWait, but returns immediately.
	/// @returns The \see ProcessInfo of the newly launched process.
	/// \note On Microsoft Windows systems, users will need to either call
	/// \see Wait until the process finished execution or win32 CloseHandle() API
	/// on ProcessInfo.ProcessHandle to avoid memory leaks.
	ProcessInfo ExecuteNoWait(StringRef Program, ArrayRef<StringRef> Args,
	Optional<ArrayRef<StringRef>> Env,
	ArrayRef<Optional<StringRef>> Redirects = {},
	unsigned MemoryLimit = 0,
	std::string *ErrMsg = nullptr,
	bool *ExecutionFailed = nullptr,
	BitVector *AffinityMask = nullptr);

	/// Return true if the given arguments fit within system-specific
	/// argument length limits.
	bool commandLineFitsWithinSystemLimits(StringRef Program,
	ArrayRef<StringRef> Args);

	/// Return true if the given arguments fit within system-specific
	/// argument length limits.
	bool commandLineFitsWithinSystemLimits(StringRef Program,
	ArrayRef<const char *> Args);

	/// File encoding options when writing contents that a non-UTF8 tool will
	/// read (on Windows systems). For UNIX, we always use UTF-8.
	enum WindowsEncodingMethod {
	/// UTF-8 is the LLVM native encoding, being the same as "do not perform
	/// encoding conversion".
	WEM_UTF8,
	WEM_CurrentCodePage,
	WEM_UTF16
	};

	/// Saves the UTF8-encoded \p contents string into the file \p FileName
	/// using a specific encoding.
	///
	/// This write file function adds the possibility to choose which encoding
	/// to use when writing a text file. On Windows, this is important when
	/// writing files with internationalization support with an encoding that is
	/// different from the one used in LLVM (UTF-8). We use this when writing
	/// response files, since GCC tools on MinGW only understand legacy code
	/// pages, and VisualStudio tools only understand UTF-16.
	/// For UNIX, using different encodings is silently ignored, since all tools
	/// work well with UTF-8.
	/// This function assumes that you only use UTF-8 text data and will convert
	/// it to your desired encoding before writing to the file.
	///
	/// FIXME: We use EM_CurrentCodePage to write response files for GNU tools in
	/// a MinGW/MinGW-w64 environment, which has serious flaws but currently is
	/// our best shot to make gcc/ld understand international characters. This
	/// should be changed as soon as binutils fix this to support UTF16 on mingw.
	///
	/// \returns non-zero error_code if failed
	std::error_code
	writeFileWithEncoding(StringRef FileName, StringRef Contents,
	WindowsEncodingMethod Encoding = WEM_UTF8);

	/// This function waits for the process specified by \p PI to finish.
	/// \returns A \see ProcessInfo struct with Pid set to:
	/// \li The process id of the child process if the child process has changed
	/// state.
	/// \li 0 if the child process has not changed state.
	/// \note Users of this function should always check the ReturnCode member of
	/// the \see ProcessInfo returned from this function.
	ProcessInfo Wait(
	const ProcessInfo &PI, ///< The child process that should be waited on.
	unsigned SecondsToWait, ///< 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 function returns. If zero, this function
	///< will perform a non-blocking wait on the child process.
	bool WaitUntilTerminates, ///< If true, ignores \p SecondsToWait and waits
	///< until child has terminated.
	std::string *ErrMsg = nullptr, ///< 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.
	Optional<ProcessStatistics> *ProcStat = nullptr ///< If non-zero, provides
	/// a pointer to a structure in which process execution statistics will be
	/// stored.
	);

	/// Print a command argument, and optionally quote it.
	void printArg(llvm::raw_ostream &OS, StringRef Arg, bool Quote);

	#if defined(_WIN32)
	/// Given a list of command line arguments, quote and escape them as necessary
	/// to build a single flat command line appropriate for calling CreateProcess
	/// on
	/// Windows.
	ErrorOr<std::wstring> flattenWindowsCommandLine(ArrayRef<StringRef> Args);
	#endif
	}
	}

	#endif