util-memory: Memory utility functions

CMakeLists.txt

@@ -49,6 +49,7 @@ SET(obs-stream-effects_HEADERS
 	"${PROJECT_BINARY_DIR}/source/version.h"
 	"${PROJECT_SOURCE_DIR}/source/strings.h"
 	"${PROJECT_SOURCE_DIR}/source/util-math.h"
+	"${PROJECT_SOURCE_DIR}/source/util-memory.h"
 )
 SET(obs-stream-effects_SOURCES
 	"${PROJECT_SOURCE_DIR}/source/plugin.cpp"
@@ -67,6 +68,7 @@ SET(obs-stream-effects_SOURCES
 	"${PROJECT_SOURCE_DIR}/source/gs-vertexbuffer.cpp"
 	"${PROJECT_SOURCE_DIR}/source/gs-mipmapper.cpp"
 	"${PROJECT_SOURCE_DIR}/source/util-math.cpp"
+	"${PROJECT_SOURCE_DIR}/source/util-memory.cpp"
 )
 SET(obs-stream-effects_LOCALE
 	"${PROJECT_SOURCE_DIR}/data/locale/en-US.ini"

source/util-memory.cpp

@@ -0,0 +1,47 @@
+/*
+* Modern effects for a modern Streamer
+* Copyright (C) 2017 Michael Fabian Dirks
+*
+* 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 2 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, write to the Free Software
+* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
+*/
+
+#include "util-memory.h"
+#include <cstdlib>
+
+inline size_t aligned_offset(size_t align, size_t size) {
+	return ((size / align) + 1) * align;
+}
+
+void* util::aligned_malloc(size_t align, size_t size) {
+	// Ensure that we have space for the pointer and the data.
+	size_t asize = aligned_offset(align, size + sizeof(void*));
+
+	// Allocate memory and store integer representation of pointer.
+	void* ptr = malloc(asize);
+
+	// Calculate actual aligned position
+	intptr_t ptr_off = aligned_offset(align, reinterpret_cast<size_t>(ptr)+sizeof(void*));
+
+	// Store actual pointer at ptr_off - sizeof(void*).
+	*reinterpret_cast<intptr_t*>(ptr_off - sizeof(void*)) = reinterpret_cast<intptr_t>(ptr);
+
+	// Return aligned pointer
+	return reinterpret_cast<void*>(ptr_off);
+}
+
+void util::free_aligned(void* mem) {
+	void* ptr = reinterpret_cast<void*>(*reinterpret_cast<intptr_t*>(static_cast<char*>(mem)-sizeof(void*)));
+	free(ptr);
+}

source/util-memory.h

@@ -0,0 +1,25 @@
+/*
+ * Modern effects for a modern Streamer
+ * Copyright (C) 2017 Michael Fabian Dirks
+ *
+ * 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 2 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, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
+ */
+
+#pragma once
+
+namespace util {
+	void* aligned_malloc(size_t align, size_t size);
+	void free_aligned(void* mem);
+};