namespace llvm {
class error_code;
namespace sys {
- /// 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). Paths with slashes are
- /// returned unmodified.
- /// @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.
- /// @brief Construct a Program by finding it by name.
+
+ /// 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 (LLVM_ON_WIN32)
+ const char EnvPathSeparator = ';';
+#endif
+
+/// @brief This struct encapsulates information about a process.
+struct ProcessInfo {
+#if defined(LLVM_ON_UNIX)
+ typedef pid_t ProcessId;
+#elif defined(LLVM_ON_WIN32)
+ typedef unsigned long ProcessId; // Must match the type of DWORD on Windows.
+ typedef void * HANDLE; // Must match the type of HANDLE on Windows.
+ /// The handle to the process (available on Windows only).
+ HANDLE ProcessHandle;
+#else
+#error "ProcessInfo is not defined for this platform!"
+#endif
+
+ /// The process identifier.
+ ProcessId Pid;
+
+ /// The return code, set after execution.
+ int ReturnCode;
+
+ ProcessInfo();
+};
+
+ /// This function attempts 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). Paths with slashes are returned unmodified.
+ ///
+ /// It 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.
+ ///
+ /// @returns A string containing the path of the program or an empty string if
+ /// the program could not be found.
std::string FindProgramByName(const std::string& name);
// These functions change the specified standard stream (stdin, stdout, or
/// invoked program will inherit the stdin, stdout, and stderr file
/// descriptors, the environment and other configuration settings of the
/// invoking program.
- /// This function waits the program to finish.
+ /// 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
///< program.
bool *ExecutionFailed = 0);
- /// Similar to ExecuteAndWait, but return immediately.
- void ExecuteNoWait(StringRef Program, const char **args, const char **env = 0,
- const StringRef **redirects = 0, unsigned memoryLimit = 0,
- std::string *ErrMsg = 0);
+ /// 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, const char **args, const char **env = 0,
+ const StringRef **redirects = 0, unsigned memoryLimit = 0,
+ std::string *ErrMsg = 0, bool *ExecutionFailed = 0);
- // Return true if the given arguments fit within system-specific
- // argument length limits.
+ /// Return true if the given arguments fit within system-specific
+ /// argument length limits.
bool argumentsFitWithinSystemLimits(ArrayRef<const char*> Args);
-}
+
+ /// 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 = 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.
+ );
+ }
}
#endif