alloc: New header for memory allocation utilities

1 files changed, 50 insertions, 0 deletions

diff --git a/src/alloc.c b/src/alloc.c
new file mode 100644
index 0000000..0003108
--- /dev/null
+++ b/src/alloc.c
@@ -0,0 +1,50 @@
+// Copyright © Tavian Barnes <tavianator@tavianator.com>
+// SPDX-License-Identifier: 0BSD
+
+#include "alloc.h"
+#include "bit.h"
+#include "diag.h"
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+
+/** Portable aligned_alloc()/posix_memalign(). */
+static void *xmemalign(size_t align, size_t size) {
+	bfs_assert(has_single_bit(align));
+	bfs_assert(align >= sizeof(void *));
+	bfs_assert((size & (align - 1)) == 0);
+
+#if __APPLE__
+	void *ptr = NULL;
+	errno = posix_memalign(&ptr, align, size);
+	return ptr;
+#else
+	return aligned_alloc(align, size);
+#endif
+}
+
+void *alloc(size_t align, size_t size) {
+	bfs_assert(has_single_bit(align));
+	bfs_assert((size & (align - 1)) == 0);
+
+	if (align <= alignof(max_align_t)) {
+		return malloc(size);
+	} else {
+		return xmemalign(align, size);
+	}
+}
+
+void *zalloc(size_t align, size_t size) {
+	bfs_assert(has_single_bit(align));
+	bfs_assert((size & (align - 1)) == 0);
+
+	if (align <= alignof(max_align_t)) {
+		return calloc(1, size);
+	}
+
+	void *ret = xmemalign(align, size);
+	if (ret) {
+		memset(ret, 0, size);
+	}
+	return ret;
+}