Re-landing "Refactoring cl::list_storage from "is a" to "has a" std::vector."

[oota-llvm.git] / include / llvm / Support / Program.h

diff --git a/include/llvm/Support/Program.h b/include/llvm/Support/Program.h
index 01165e8bf7484dae7799b3b9a5064ed5b8f66aab..b89a0f73ec681e491f3b7cd9fdf4dd833eeff402 100644 (file)
--- a/include/llvm/Support/Program.h
+++ b/include/llvm/Support/Program.h
@@ -15,10 +15,12 @@
 #define LLVM_SUPPORT_PROGRAM_H
 
 #include "llvm/ADT/ArrayRef.h"
-#include "llvm/Support/Path.h"
+#include "llvm/Support/ErrorOr.h"
 #include <system_error>
 
 namespace llvm {
+class StringRef;
+
 namespace sys {
 
   /// This is the OS-specific separator for PATH like environment variables:
@@ -51,17 +53,22 @@ struct ProcessInfo {
   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.
+  /// \brief Find the first executable file \p Name in \p Paths.
   ///
-  /// It does not perform hashing as a shell would but instead stats each PATH
+  /// 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.
   ///
-  /// @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);
+  /// \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 = ArrayRef<StringRef>());
 
   // These functions change the specified standard stream (stdin or stdout) to
   // binary mode. They return errc::success if the specified stream
@@ -82,7 +89,7 @@ struct ProcessInfo {
   /// -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.
+      /// 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.