Deduplicate load-or-import code from plugins

plugins/lv2/sfizz.cpp

@@ -35,7 +35,7 @@
 #include "sfizz_lv2.h"
 #include "sfizz_lv2_plugin.h"
 
-#include "sfizz/import/ForeignInstrument.h"
+#include "sfizz/import/sfizz_import.h"
 #include "plugin/InstrumentDescription.h"
 
 #include <math.h>
@@ -1231,8 +1231,6 @@ sfizz_lv2_update_sfz_info(sfizz_plugin_t *self)
 static bool
 sfizz_lv2_load_file(sfizz_plugin_t *self, const char *file_path)
 {
-    bool status;
-
     char buf[MAX_PATH_SIZE];
     if (file_path[0] == '\0')
     {
@@ -1241,18 +1239,7 @@ sfizz_lv2_load_file(sfizz_plugin_t *self, const char *file_path)
     }
 
     ///
-    const sfz::InstrumentFormatRegistry& formatRegistry = sfz::InstrumentFormatRegistry::getInstance();
-    const sfz::InstrumentFormat* format = formatRegistry.getMatchingFormat(file_path);
-
-    if (!format)
-        status = sfizz_load_file(self->synth, file_path);
-    else {
-        auto importer = format->createImporter();
-        std::string virtual_path = std::string(file_path) + ".sfz";
-        std::string sfz_text = importer->convertToSfz(file_path);
-        status = sfizz_load_string(self->synth, virtual_path.c_str(), sfz_text.c_str());
-    }
-
+    bool status = sfizz_load_or_import_file(self->synth, file_path, nullptr);
     sfizz_lv2_update_sfz_info(self);
     sfizz_lv2_update_file_info(self, file_path);
     return status;

plugins/vst/SfizzVstProcessor.cpp

@@ -9,7 +9,7 @@
 #include "SfizzVstState.h"
 #include "SfizzVstParameters.h"
 #include "SfizzVstIDs.h"
-#include "sfizz/import/ForeignInstrument.h"
+#include "sfizz/import/sfizz_import.h"
 #include "plugin/SfizzFileScan.h"
 #include "plugin/InstrumentDescription.h"
 #include "base/source/fstreamer.h"
@@ -682,16 +682,7 @@ void SfizzVstProcessor::loadSfzFileOrDefault(const std::string& filePath, bool i
     sfz::Sfizz& synth = *_synth;
 
     if (!filePath.empty()) {
-        const sfz::InstrumentFormatRegistry& formatRegistry = sfz::InstrumentFormatRegistry::getInstance();
-        const sfz::InstrumentFormat* format = formatRegistry.getMatchingFormat(filePath);
-        if (!format)
-            synth.loadSfzFile(filePath);
-        else {
-            auto importer = format->createImporter();
-            std::string virtualPath = filePath + ".sfz";
-            std::string sfzText = importer->convertToSfz(filePath);
-            synth.loadSfzString(virtualPath, sfzText);
-        }
+        sfizz_load_or_import_file(synth.handle(), filePath.c_str(), nullptr);
     }
     else {
         synth.loadSfzString("default.sfz", defaultSfzText);

src/CMakeLists.txt

@@ -251,11 +251,13 @@ endif()
 
 # Import library
 set(SFIZZ_IMPORT_HEADERS
+    sfizz/import/sfizz_import.h
     sfizz/import/ForeignInstrument.h
     sfizz/import/foreign_instruments/AudioFile.h
     sfizz/import/foreign_instruments/DecentSampler.h)
 
 set(SFIZZ_IMPORT_SOURCES
+    sfizz/import/sfizz_import.cpp
     sfizz/import/ForeignInstrument.cpp
     sfizz/import/foreign_instruments/AudioFile.cpp
     sfizz/import/foreign_instruments/DecentSampler.cpp)

src/sfizz/import/sfizz_import.cpp

@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: BSD-2-Clause
+
+// This code is part of the sfizz library and is licensed under a BSD 2-clause
+// license. You should have receive a LICENSE.md file along with the code.
+// If not, contact the sfizz maintainers at https://github.com/sfztools/sfizz
+
+#include "sfizz.h"
+#include "sfizz_import.h"
+#include "ForeignInstrument.h"
+
+bool sfizz_load_or_import_file(sfizz_synth_t* synth, const char* path, const char** format)
+{
+    const sfz::InstrumentFormatRegistry& ireg = sfz::InstrumentFormatRegistry::getInstance();
+    const sfz::InstrumentFormat* ifmt = ireg.getMatchingFormat(path);
+
+    if (!ifmt) {
+        if (!sfizz_load_file(synth, path))
+            return false;
+        if (format)
+            *format = nullptr;
+    }
+    else {
+        auto importer = ifmt->createImporter();
+        std::string virtualPath = std::string(path) + ".sfz";
+        std::string sfzText = importer->convertToSfz(path);
+        if (!sfizz_load_string(synth, virtualPath.c_str(), sfzText.c_str()))
+            return false;
+        if (format)
+            *format = ifmt->name();
+    }
+
+    return true;
+}

src/sfizz/import/sfizz_import.h

@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: BSD-2-Clause
+
+// This code is part of the sfizz library and is licensed under a BSD 2-clause
+// license. You should have receive a LICENSE.md file along with the code.
+// If not, contact the sfizz maintainers at https://github.com/sfztools/sfizz
+
+#pragma once
+
+typedef struct sfizz_synth_t sfizz_synth_t;
+
+/**
+ * @brief Loads or imports an instrument file.
+ *
+ * The file path can be absolute or relative.
+ * @since 1.0.1
+ *
+ * @param synth   The synth.
+ * @param path    A null-terminated string representing a path to an instrument
+ *                in SFZ format, or another format which can be imported.
+ * @param format  An optional pointer to a string pointer, which receives the
+ *                null-terminated name of the format if the file was imported,
+ *                or null if the file was loaded directly as SFZ.
+ *
+ * @return @true when file loading went OK,
+ *         @false if some error occured while loading.
+ *
+ * @par Thread-safety constraints
+ * - @b CT: the function must be invoked from the Control thread
+ * - @b OFF: the function cannot be invoked while a thread is calling @b RT functions
+ */
+bool sfizz_load_or_import_file(sfizz_synth_t* synth, const char* path, const char** format);