Add crossplatform dynamic library loading related stuff

src/rvdl.c

@@ -0,0 +1,182 @@
+/*
+rvdl.c - Dynamic library related stuff implementation
+Copyright (C) 2023 0xCatPKG <github.com/0xCatPKG>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#include <string.h>
+#include <stdio.h>
+
+#include "rvdl.h"
+#include "utils.h"
+
+#ifndef NO_DLOPEN
+
+#ifdef _WIN32
+#include <windows.h>
+#include <libloaderapi.h>
+#else
+#include <dlfcn.h>
+#endif
+
+rvdlib* rvdlib_open(const char* path, uint16_t flags)
+{
+    int oflags = 0;
+    void* dl_handle = NULL;
+
+#ifdef _WIN32
+    HMODULE win_handle = GetModuleHandleA((LPSTR)path);
+    if (!win_handle)
+    {
+        if (flags & RVDLIB_NOLOAD)
+        {
+            oflags |= LOAD_LIBRARY_AS_DATAFILE;
+        }
+        win_handle = LoadLibraryExA((LPSTR)path, NULL, (DWORD)oflags);
+        if (!win_handle) {
+            rvvm_error("rvdlib_open failed");
+            return NULL;
+        }
+        dl_handle = (void*)win_handle;
+    }
+
+#else
+    if (flags & RVDLIB_NOW)
+    {
+        oflags = RTLD_NOW;
+    } else {
+        oflags = RTLD_LAZY;
+    }
+
+    if (flags & RVDLIB_NODELETE) {
+        oflags |= RTLD_NODELETE;
+    }
+
+    if (flags & RVDLIB_NOLOAD) {
+        oflags |= RTLD_NOLOAD;
+    }
+
+    dl_handle = dlopen(path, oflags);
+    if (!dl_handle) {
+
+        rvvm_error("rvdlib_open failed: %s", dlerror());
+        return NULL;
+    }
+#endif
+    rvdlib* handle = safe_new_obj(rvdlib);
+    handle->library_handle = dl_handle;
+    strcpy(handle->library_path, path);
+    handle->flags = flags;
+    return handle;
+}
+
+void rvdlib_close(rvdlib* handle)
+{
+    if (!handle)
+    {
+        rvvm_error("rvdlib_close: Invalid dynamic library handle");
+        return;
+    }
+
+#ifdef _WIN32
+    if (!(handle->flags & RVDLIB_NODELETE))
+    {
+        if (!FreeLibrary((HMODULE)handle->library_handle))
+        {
+            rvvm_error("rvdlib_close failed");
+        }
+    }
+#else
+    if (dlclose(handle->library_handle))
+    {
+        rvvm_error("rvdlib_close failed: %s", dlerror());
+    }
+#endif
+    free(handle);
+}
+
+void* rvdlib_resolve(rvdlib* handle, const char* symbol_name)
+{
+    if (!handle)
+    {
+        rvvm_error("rvdlib_resolve: Invalid dynamic library handle");
+        return NULL;
+    }
+    void* fn_ptr = NULL;
+#ifdef _WIN32
+    fn_ptr = (void*)GetProcAddress((HMODULE)handle->library_handle, (LPSTR)symbol_name);
+    if (!fn_ptr)
+    {
+        rvvm_error("rvdlib_resolve failed");
+        return NULL;
+    }
+#else
+    fn_ptr = dlsym(handle->library_handle, symbol_name);
+    if (!fn_ptr)
+    {
+        rvvm_error("rvdlib_resolve: symbol resolve error: %s", dlerror());
+        return NULL;
+    }
+#endif
+    return fn_ptr;
+}
+
+rvdlib* rvdlib_reopen(rvdlib* handle, uint16_t flags)
+{
+    if (!handle)
+    {
+        rvvm_error("rvdlib_reopen: Invalid dynamic library handle");
+        return NULL;
+    }
+    char library_path[256];
+    memset(library_path, 0, 256);
+    memcpy(handle->library_path, library_path, 256);
+    rvdlib_close(handle);
+    return rvdlib_open(library_path, flags);
+}
+
+#else
+
+rvdlib* rvdlib_open(const char* path, uint16_t flags)
+{
+    UNUSED(path);
+    UNUSED(flags);
+    rvvm_error("rvdlib_open: Dynamic loading not supported");
+    return NULL;
+}
+
+rvdlib* rvdlib_reopen(rvdlib* handle, uint16_t flags)
+{
+    UNUSED(handle);
+    UNUSED(flags);
+    rvvm_error("rvdlib_reopen: Dynamic loading not supported");
+    return NULL;
+}
+
+void rvdlib_close(rvdlib* handle)
+{
+    UNUSED(handle);
+    rvvm_error("rvdlib_close: Dynamic loading not supported");
+}
+
+void* rvdlib_resolve(rvdlib* handle, const char* symbol_name)
+{
+    UNUSED(handle);
+    UNUSED(symbol_name);
+    rvvm_error("rvdlib_resolve: Dynamic loading not supported");
+    return NULL;
+}
+
+#endif

src/rvdl.h

@@ -0,0 +1,45 @@
+/*
+rvdl.h - Dynamic library related stuff
+Copyright (C) 2023 0xCatPKG <github.com/0xCatPKG>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#ifndef RVDL_H
+#define RVDL_H
+
+#include "compiler.h"
+
+#define RVDLIB_LAZY 0 // Default behavior, resolve syms only in rvdlib_resolve
+#define RVDLIB_NOW  1 // Takes no effect on Windows as i not found how to list all procedures by HMODULE
+
+#define RVDLIB_NODELETE 1 << 1 // Do not really unload dynamic object in rvdlib_close, just free handle
+#define RVDLIB_NOLOAD   1 << 2 // Do not really load dynamic object in rvdlib_open, just check if it exists in lookup directories, rvdlib_open will return NULL if dynamic object not found
+
+typedef struct 
+{
+    void* library_handle;
+    char library_path[256];
+    uint16_t flags;
+} rvdlib;
+
+// rvdlib managment methods
+rvdlib* rvdlib_open(const char* path, uint16_t flags);
+rvdlib* rvdlib_reopen(rvdlib* handle, uint16_t flags);
+void rvdlib_close(rvdlib* handle);
+
+// Symbol managment methods
+void* rvdlib_resolve(rvdlib* handle, const char* symbol_name);
+
+#endif