Move PBD::canonical_path to pbd/file_utils.h/cc and reimplement for Windows

This fixes the libpbd testCanonicalPathUTF8 and libardour
open_session_utf8_path unit tests

You can now have Sessions with localized names containing characters that
aren't in the system codepage on Windows.

It also fixes the issue where a Session would not open when it was moved into a
path with characters that aren't in the system codepage.

The only use case for calling canonical_path/realpath on the session path
AFAICT is for resolving relative paths that are passed via the command
line/terminal. I'm doubtful that works correctly on Windows because of
character encoding issues with the current API we use for that(not glib), so it
is slightly ironic that this issue was caused by an incorrect implementation of
a function that is not really necessary on Windows at this point in time.

1 files changed, 59 insertions, 0 deletions

diff --git a/libs/pbd/file_utils.cc b/libs/pbd/file_utils.cc
index 26f80f9719..63df6ee3c7 100644
--- a/libs/pbd/file_utils.cc
+++ b/libs/pbd/file_utils.cc
@@ -361,6 +361,65 @@ get_absolute_path (const std::string & p)
 	return Glib::build_filename (Glib::get_current_dir(), p);
 }
 
+string
+canonical_path (const std::string& path)
+{
+#ifdef PLATFORM_WINDOWS
+	wchar_t resolved_wpath[_MAX_PATH];
+
+	// sizeof(wchar_t) is 2 bytes using gcc/mingw and VC++ but 4 bytes using gcc/linux
+	assert (sizeof(wchar_t) == 2);
+
+	wchar_t* wfilepath = (wchar_t*)g_utf8_to_utf16 (path.c_str(), -1, NULL, NULL, NULL);
+
+	if (wfilepath == NULL) {
+		DEBUG_TRACE (
+		    DEBUG::FileUtils,
+		    string_compose ("PBD::canonical_path: Unable to convert path from utf8 to utf16 : %1\n",
+		                    path));
+		return path;
+	}
+
+	if (_wfullpath (resolved_wpath, wfilepath, _MAX_PATH) == NULL) {
+		DEBUG_TRACE (DEBUG::FileUtils,
+		             string_compose ("PBD::canonical_path: Unable to resolve %1\n", wfilepath));
+		return path;
+	}
+
+	gchar* resolved_utf8_path =
+	    g_utf16_to_utf8 (reinterpret_cast<const gunichar2*>(resolved_wpath), -1, NULL, NULL, NULL);
+
+	if (resolved_utf8_path == NULL) {
+		DEBUG_TRACE (
+		    DEBUG::FileUtils,
+		    string_compose ("PBD::canonical_path: Unable to convert path from utf16 to utf8 : %1\n",
+		                    resolved_wpath));
+		return path;
+	}
+
+	const string retval(resolved_utf8_path);
+
+	g_free (wfilepath);
+	g_free (resolved_utf8_path);
+
+	return retval;
+
+#else
+	char buf[PATH_MAX+1];
+
+	if (realpath (path.c_str(), buf) == NULL) {
+		DEBUG_TRACE (DEBUG::FileUtils,
+		             string_compose ("PBD::canonical_path: Unable to resolve %1: %2\n", path,
+		                             g_strerror (errno)));
+		return path;
+	}
+	DEBUG_TRACE (DEBUG::FileUtils,
+	             string_compose ("PBD::canonical_path %1 resolved to: %2\n", path, string (buf)));
+
+	return string (buf);
+#endif
+}
+
 std::string
 get_suffix (const std::string & p)
 {