Wrap dlopen/dlsym

include/ground.h

@@ -7,6 +7,14 @@
 #include <stdbool.h>
 #include <uthash.h>
 
+#ifdef _WIN32
+// TODO: check if this works
+#include <minwindef.h>
+#define PATH_MAX MAX_PATH
+#else 
+#include <limits.h>
+#endif
+
 // 
 // TYPES
 //
@@ -352,6 +360,11 @@ struct GroundExecutionResult {
     } as;
 };
 
+struct GroundOpenSharedObjects {
+    char path[PATH_MAX];
+    void* handle;
+    UT_hash_handle hh;
+};
 
 // 
 // INTERFACE
@@ -522,6 +535,12 @@ struct _Ground {
 
         char* (*BytecodeValue)(GroundBytecodeValue* value);
     } Stringify;
+
+    struct {
+        struct GroundOpenSharedObjects* objects;
+        void* (*openSharedObject)(char* id);
+        void* (*getFunction)(void* handle, char* id);
+    } FFI;
 };
 
 extern struct _Ground Ground;

meson.build

@@ -27,6 +27,9 @@ sources = files(
 
     'src/Copy/BytecodeValue.c',
 
+    'src/FFI/openSharedObject.c',
+    'src/FFI/getFunction.c',
+
     'src/Free/Function.c',
     'src/Free/List.c',
     'src/Free/Object.c',

src/FFI/getFunction.c

@@ -0,0 +1,22 @@
+#include "../../include/ground.h"
+
+#ifdef _WIN32
+// TODO: Windows support
+#else
+#include <dlfcn.h>
+#endif
+
+void* _GroundFFIGetFunction(void* handle, char* id) {
+#ifdef _WIN32
+    // TODO: Windows support
+#else
+    void* function = dlsym(handle, id);
+    char* error = dlerror();
+    if (error != NULL) {
+        Ground.Log.Error(error);
+        Ground.Flags.error = true;
+        return NULL;
+    }
+    return function;
+#endif
+}

src/FFI/openSharedObject.c

@@ -0,0 +1,45 @@
+#include "../../include/ground.h"
+
+#include <ffi.h>
+
+#ifdef _WIN32
+// TODO: Windows support
+#else 
+#include <dlfcn.h>
+#endif
+
+void* _GroundFFIOpenSharedObject(char* id) {
+
+    struct GroundOpenSharedObjects* object = NULL;
+    HASH_FIND_STR(Ground.FFI.objects, id, object);
+
+    if (object != NULL) {
+        return object->handle;
+    }
+
+    void* handle = NULL;
+
+#ifdef _WIN32 
+    // TODO: Windows support
+#else 
+    // Assume POSIX platform
+    handle = dlopen(id, RTLD_LAZY);
+    if (handle == NULL) {
+        Ground.Log.Error(dlerror());
+        Ground.Flags.error = true;
+        return NULL;
+    }
+
+#endif
+
+    object = malloc(sizeof(struct GroundOpenSharedObjects));
+    if (object == NULL) {
+        Ground.Log.Error("malloc failed in Ground.FFI.openSharedObject");
+        Ground.Flags.error = true;
+        return NULL;
+    }
+    object->handle = handle;
+    snprintf(object->path, sizeof(object->path), "%s", id);
+    HASH_ADD_STR(Ground.FFI.objects, path, object);
+    return handle;
+}

src/libmain.c

@@ -122,6 +122,8 @@ char* _GroundStringifyValue(GroundValue* value);
 
 char* _GroundStringifyBytecodeValue(GroundBytecodeValue* value);
 
+void* _GroundFFIOpenSharedObject(char* id);
+void* _GroundFFIGetFunction(void* handle, char* id);
 
 struct _Ground Ground = {
 
@@ -273,4 +275,10 @@ struct _Ground Ground = {
 
         .BytecodeValue = _GroundStringifyBytecodeValue,
     },
+
+    .FFI = {
+        .objects = NULL,
+        .openSharedObject = _GroundFFIOpenSharedObject,
+        .getFunction = _GroundFFIGetFunction,
+    },
 };