private void ValidateEntryPointPath(string serviceManifestFileName, FileLocator fileLocator, string program, bool isExternalExecutable = false)
        {
            string entryPointPath = this.GetEntryPointPath(program, serviceManifestFileName);

            if (string.IsNullOrEmpty(entryPointPath))
            {
                ImageBuilderUtility.TraceAndThrowValidationErrorWithFileName(
                    TraceType,
                    serviceManifestFileName,
                    StringResources.ImageBuilderError_NullOrEmptyError,
                    "EntryPoint");
            }
            else if (entryPointPath.IndexOfAny(System.IO.Path.GetInvalidPathChars()) != -1)
            {
                ImageBuilderUtility.TraceAndThrowValidationErrorWithFileName(
                    TraceType,
                    serviceManifestFileName,
                    StringResources.ImageBuilderError_InvalidValue,
                    "EntryPoint",
                    entryPointPath);
            }
            else if (System.IO.Path.IsPathRooted(entryPointPath))
            {
                ImageBuilderUtility.TraceAndThrowValidationErrorWithFileName(
                    TraceType,
                    serviceManifestFileName,
                    StringResources.ImageBuilderError_RootedEntryPointNotSupported,
                    entryPointPath);
            }

            if (isExternalExecutable)
            {
                ImageBuilder.TraceSource.WriteInfo(
                    TraceType,
                    "EntryPointPath {0} is external executable",
                    entryPointPath);
            }
            else if (!fileLocator.FileExists(entryPointPath))
            {
#if !DotNetCoreClrLinux
                if (string.IsNullOrEmpty(Path.GetExtension(entryPointPath)) && fileLocator.FileExists(entryPointPath + ".exe"))
                {
                    return;
                }
#endif
                ImageBuilderUtility.TraceAndThrowValidationErrorWithFileName(
                    TraceType,
                    serviceManifestFileName,
                    StringResources.ImageBuilderError_EntryPointNotFound,
                    entryPointPath);
            }
        }