Fix sfztools#95: replace \ with / on Windows when saving file paths.

... and do vice versa on restore.

plugins/common/plugin/NativeHelpers.cpp

@@ -12,6 +12,28 @@
 #include <cstdlib>
 #include <fstream>
 
+
+#if defined(_WIN32)
+const fs::path toPlatformAgnosticPath(std::string& filePath)
+{
+    return fs::u8path(filePath.replace(filePath.begin(), filePath.end(), '\\', '/'));
+}
+const fs::path fromPlatformAgnosticPath(const char *filePath)
+{
+    std::string p{filePath};
+    return fs::u8path(p.replace(p.begin(), p.end(), '/', '\\'));
+}
+#else
+const fs::path toPlatformAgnosticPath(std::string& filePath)
+{
+    return fs::u8path(filePath);
+}
+const fs::path fromPlatformAgnosticPath(const char *filePath)
+{
+    return fs::u8path(filePath);
+}
+#endif
+
 #if defined(_WIN32)
 #include <windows.h>
 #include <shlobj.h>

plugins/common/plugin/NativeHelpers.h

@@ -13,6 +13,9 @@
 
 const fs::path& getUserDocumentsDirectory();
 
+const fs::path toPlatformAgnosticPath(std::string& filePath);
+const fs::path fromPlatformAgnosticPath(const char *filePath);
+
 #if !defined(_WIN32) && !defined(__APPLE__)
 const fs::path& getUserHomeDirectory();
 const fs::path& getXdgConfigHome();

plugins/vst/SfizzVstProcessor.cpp

@@ -12,6 +12,7 @@
 #include "sfizz/import/sfizz_import.h"
 #include "plugin/SfizzFileScan.h"
 #include "plugin/InstrumentDescription.h"
+#include "plugin/NativeHelpers.h"
 #include "base/source/fstreamer.h"
 #include "base/source/updatehandler.h"
 #include "pluginterfaces/vst/ivstevents.h"
@@ -178,7 +179,8 @@ tresult PLUGIN_API SfizzVstProcessor::setState(IBStream* stream)
         if (statePath->empty())
             continue;
 
-        fs::path pathOrig = fs::u8path(*statePath);
+        // save file path in platform-agnostic way. See sfizz-ui issue #95
+        fs::path pathOrig = toPlatformAgnosticPath(*statePath);
         std::error_code ec;
         if (fs::is_regular_file(pathOrig, ec))
             continue;

plugins/vst/SfizzVstState.cpp

@@ -5,6 +5,7 @@
 // If not, contact the sfizz maintainers at https://github.com/sfztools/sfizz
 
 #include "SfizzVstState.h"
+#include "plugin/NativeHelpers.h"
 #include <sfizz.h>
 #include <mutex>
 #include <cstring>
@@ -21,7 +22,7 @@ tresult SfizzVstState::load(IBStream* state)
         return kResultFalse;
 
     if (const char* str = s.readStr8())
-        sfzFile = str;
+        sfzFile = fromPlatformAgnosticPath(str);
     else
         return kResultFalse;
 
@@ -41,7 +42,7 @@ tresult SfizzVstState::load(IBStream* state)
 
     if (version >= 1) {
         if (const char* str = s.readStr8())
-            scalaFile = str;
+            scalaFile = fromPlatformAgnosticPath(str);
         else
             return kResultFalse;