Adding rcutils_to_native_path function

include/rcutils/filesystem.h

@@ -126,6 +126,24 @@ rcutils_join_path(
   const char * right_hand_path,
   rcutils_allocator_t allocator);
 
+/// Return newly allocated string with all argument's "/" replaced by platform specific separator.
+/**
+ * This function allocates memory and returns it to the caller.
+ * It is up to the caller to release the memory once it is done with it by
+ * calling `deallocate` on the same allocator passed here.
+ *
+ * \param[in] path
+ * \param[in] allocator
+ * \return char * path using platform specific delimiters on success
+ *         NULL on invalid arguments
+ *         NULL on failure
+ */
+RCUTILS_PUBLIC
+char *
+rcutils_to_native_path(
+  const char * path,
+  rcutils_allocator_t allocator);
+
 #ifdef __cplusplus
 }
 #endif

src/filesystem.c

@@ -29,6 +29,13 @@ extern "C"
 #endif  // _WIN32
 
 #include "rcutils/format_string.h"
+#include "rcutils/repl_str.h"
+
+#ifdef _WIN32
+# define RCUTILS_PATH_DELIMITER "\\"
+#else
+# define RCUTILS_PATH_DELIMITER "/"
+#endif  // _WIN32
 
 bool
 rcutils_get_cwd(char * buffer, size_t max_length)
@@ -152,13 +159,22 @@ rcutils_join_path(
     return NULL;
   }
 
-#ifdef  _WIN32
-  const char * delimiter = "\\";
-#else
-  const char * delimiter = "/";
-#endif  // _WIN32
+  return rcutils_format_string(
+    allocator,
+    "%s%s%s",
+    left_hand_path, RCUTILS_PATH_DELIMITER, right_hand_path);
+}
+
+char *
+rcutils_to_native_path(
+  const char * path,
+  rcutils_allocator_t allocator)
+{
+  if (NULL == path) {
+    return NULL;
+  }
 
-  return rcutils_format_string(allocator, "%s%s%s", left_hand_path, delimiter, right_hand_path);
+  return rcutils_repl_str(path, "/", RCUTILS_PATH_DELIMITER, &allocator);
 }
 
 #ifdef __cplusplus

test/test_filesystem.cpp

@@ -59,6 +59,35 @@ TEST_F(TestFilesystemFixture, join_path) {
   EXPECT_STREQ(ref_str, path);
 }
 
+TEST_F(TestFilesystemFixture, to_native_path) {
+  {
+    char * path = rcutils_to_native_path("/foo/bar/baz", g_allocator);
+    OSRF_TESTING_TOOLS_CPP_SCOPE_EXIT({
+      g_allocator.deallocate(path, g_allocator.state);
+    });
+#ifdef _WIN32
+    const char * ref_str = "\\foo\\bar\\baz";
+#else
+    const char * ref_str = "/foo/bar/baz";
+#endif  // _WIN32
+    ASSERT_FALSE(nullptr == path);
+    EXPECT_STREQ(ref_str, path);
+  }
+  {
+    char * path = rcutils_to_native_path("/foo//bar/baz", g_allocator);
+    OSRF_TESTING_TOOLS_CPP_SCOPE_EXIT({
+      g_allocator.deallocate(path, g_allocator.state);
+    });
+#ifdef _WIN32
+    const char * ref_str = "\\foo\\\\bar\\baz";
+#else
+    const char * ref_str = "/foo//bar/baz";
+#endif  // _WIN32
+    ASSERT_FALSE(nullptr == path);
+    EXPECT_STREQ(ref_str, path);
+  }
+}
+
 TEST_F(TestFilesystemFixture, exists) {
   {
     char * path = rcutils_join_path(this->test_path, "dummy_readable_file.txt", g_allocator);