//===- 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/Optional.h" #include "llvm/ADT/StringRef.h" #include "llvm/Config/llvm-config.h" #include "llvm/Support/ErrorOr.h" #include 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(); }; /// 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 findProgramByName(StringRef Name, ArrayRef Paths = {}); // 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 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> 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> 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); /// Similar to ExecuteAndWait, but returns immediately. /// @returns The \see ProcessInfo of the newly launced 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 Args, Optional> Env, ArrayRef> Redirects = {}, unsigned MemoryLimit = 0, std::string *ErrMsg = nullptr, bool *ExecutionFailed = nullptr); /// Return true if the given arguments fit within system-specific /// argument length limits. bool commandLineFitsWithinSystemLimits(StringRef Program, ArrayRef Args); /// Return true if the given arguments fit within system-specific /// argument length limits. bool commandLineFitsWithinSystemLimits(StringRef Program, ArrayRef 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. ); #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. std::string flattenWindowsCommandLine(ArrayRef Args); #endif } } #endif