ref

runtime/.gitignore

@@ -0,0 +1 @@
+.build

runtime/build.sh

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+#!/bin/bash
+
+set -euo pipefail
+
+mkdir -p .build
+clang -c runtime.c -o .build/runtime.o

runtime/ref.c

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+#include "ref.h"
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+void *rc_alloc(size_t size, void (*destructor)(void *self))
+{
+    printf("rc_alloc %zu bytes\n", size);
+    ref_header *header = malloc(sizeof(ref_header) + size);
+    if (!header)
+    {
+        exit(69);
+    }
+
+    header->ref_count = 1;
+    header->destructor = destructor;
+
+    return (void *)(header + 1);
+}
+
+void rc_retain(void *obj)
+{
+    printf("rc_retain\n");
+    ref_header *header = ((ref_header *)obj) - 1;
+    header->ref_count++;
+}
+
+void rc_release(void *obj)
+{
+    ref_header *header = ((ref_header *)obj) - 1;
+    printf("rc_release\n");
+    if (--header->ref_count == 0)
+    {
+        if (header->destructor)
+        {
+            header->destructor(obj);
+        }
+
+        free(header);
+        printf("rc_free\n");
+    }
+}

runtime/ref.h

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+#pragma once
+
+#include <stddef.h>
+
+typedef struct
+{
+    int ref_count;
+    void (*destructor)(void *self);
+} ref_header;
+
+void *rc_alloc(size_t size, void (*destructor)(void *self));
+void rc_retain(void *obj);
+void rc_release(void *obj);

runtime/runtime.c

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+#include "ref.c"