rename systemFile() to archSystemFile() (#252)

The previous name did not convey how the helper differs from
system.file(); the distinguishing behavior is injection of the
architecture-specific subdirectory.

Author: kevinushey

R/tbb.R

@@ -42,7 +42,7 @@ tbbLibraryPath <- function(name = NULL) {
       if (file.exists(tbbName))
          return(tbbName)
 
-      tbbName <- systemFile("lib", libName)
+      tbbName <- archSystemFile("lib", libName)
       if (file.exists(tbbName))
          return(tbbName)
 
@@ -88,7 +88,7 @@ tbbLdFlags <- function() {
    # on Windows, we statically link to oneTBB
    if (is_windows()) {
 
-      libPath <- systemFile("libs")
+      libPath <- archSystemFile("libs")
 
       ldFlags <- sprintf("-L%s -lRcppParallel", asBuildPath(libPath))
       return(ldFlags)
@@ -123,6 +123,6 @@ tbbRoot <- function() {
    if (nzchar(TBB_LIB))
       return(TBB_LIB)
 
-   systemFile("lib")
+   archSystemFile("lib")
 
 }

R/utils.R

@@ -1,7 +1,7 @@
 
 # like system.file(), but injects the architecture-specific subdirectory
-# used on Windows when set; e.g. systemFile("lib") resolves 'lib/x64'
-systemFile <- function(dir, name = NULL) {
+# used on Windows when set; e.g. archSystemFile("lib") resolves 'lib/x64'
+archSystemFile <- function(dir, name = NULL) {
    arch <- .Platform$r_arch
    parts <- c(dir, if (nzchar(arch)) arch, name)
    system.file(paste(parts, collapse = "/"), package = "RcppParallel")

R/zzz.R

@@ -23,7 +23,7 @@ loadTbbLibrary <- function(name) {
       # NOTE: resolve against the package's own library directory, where
       # install.libs.R places the stub; tbbRoot() would prefer TBB_LIB,
       # which on Windows points at Rtools and holds only static libraries
-      path <- systemFile("lib", paste0(name, ".dll"))
+      path <- archSystemFile("lib", paste0(name, ".dll"))
       if (!file.exists(path))
          return(NULL)