feat: add Dmod_ModuleExists function

inc/dmod.h

@@ -116,6 +116,7 @@ DMOD_BUILTIN_API( Dmod, 1.0, Dmod_Context_t*, _LoadModule, (const char* FilePath
  * Call this also after changing the module search path configuration.
  */
 DMOD_BUILTIN_API( Dmod, 1.0, void       , _InvalidateModuleSearchPaths, (void) );
+DMOD_BUILTIN_API( Dmod, 1.0, bool       , _ModuleExists, (const char* ModuleName) );
 DMOD_BUILTIN_API( Dmod, 1.0, bool       , _FindModuleFile, (const char* ModuleName, const char* ArchName, char* outFilePath, size_t MaxLength) );
 DMOD_BUILTIN_API( Dmod, 1.0, bool       , _FindMatch, (const char* PartialName, char* outModuleName, size_t MaxLength) );
 DMOD_BUILTIN_API( Dmod, 1.0, Dmod_Context_t*, _LoadModuleByName, (const char* ModuleName) );

src/system/dmod_system.c

@@ -580,6 +580,28 @@ Dmod_Context_t* Dmod_LoadFromPackage( const char* PackageName, const char* Modul
     return context;
 }
 
+/**
+ * @brief Check if a module exists in known locations
+ * 
+ * This function searches all module search paths (including packages) to check
+ * if a module with the given name exists. It uses the same search logic as
+ * module loading but does not attempt to load the module.
+ * 
+ * @param ModuleName Name of the module to check
+ * 
+ * @return True if module exists, false otherwise
+ */
+bool Dmod_ModuleExists(const char* ModuleName)
+{
+    if( ModuleName == NULL )
+    {
+        return false;
+    }
+
+    char filePath[256];
+    return Dmod_FindModuleFile(ModuleName, NULL, filePath, sizeof(filePath));
+}
+
 /**
  * @brief Find module file in repositories
  * 

tests/system/if/CMakeLists.txt

@@ -16,6 +16,7 @@ set(TEST_SOURCES
         ${CMAKE_CURRENT_SOURCE_DIR}/tests_dmod_module_log_level.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/tests_dmod_log_step.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/tests_dmod_str_merge.cpp
+        ${CMAKE_CURRENT_SOURCE_DIR}/tests_dmod_module_exists.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/tests_dmod_reboot.cpp
         PARENT_SCOPE
         )

tests/system/if/tests_dmod_module_exists.cpp

@@ -0,0 +1,76 @@
+/**
+ * MIT License
+ * 
+ * Copyright (c) 2025 patryk.kubiak90@gmail.com
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ * 
+ * @brief Tests for Dmod_ModuleExists function
+ * @date 24 Oct 2026
+ * 
+ * @file tests_dmod_module_exists.cpp
+ * @version 0.1
+ */
+#define DMOD_PRIVATE
+#include <gtest/gtest.h>
+#include "dmod.h"
+
+/**
+ * @brief Test for Dmod_ModuleExists with NULL module name
+ */
+TEST(DmodModuleExistsTest, NullModuleName)
+{
+    bool result = Dmod_ModuleExists(NULL);
+    ASSERT_FALSE(result);
+}
+
+/**
+ * @brief Test for Dmod_ModuleExists with empty module name
+ */
+TEST(DmodModuleExistsTest, EmptyModuleName)
+{
+    bool result = Dmod_ModuleExists("");
+    ASSERT_FALSE(result);
+}
+
+/**
+ * @brief Test for Dmod_ModuleExists with non-existent module
+ */
+TEST(DmodModuleExistsTest, NonExistentModule)
+{
+    bool result = Dmod_ModuleExists("definitely_nonexistent_module_12345");
+    ASSERT_FALSE(result);
+}
+
+/**
+ * @brief Test for Dmod_ModuleExists with existing module
+ * 
+ * This test verifies the function doesn't crash with a valid module name.
+ * The result depends on whether dmsystem is available in the search paths.
+ */
+TEST(DmodModuleExistsTest, ExistingModule)
+{
+    char outPath[256];
+    bool foundViaFind = Dmod_FindModuleFile("dmsystem", NULL, outPath, sizeof(outPath));
+
+    bool result = Dmod_ModuleExists("dmsystem");
+
+    // Dmod_ModuleExists should return the same result as Dmod_FindModuleFile
+    ASSERT_EQ(result, foundViaFind);
+}