init commit

src/internal/malloc.c

@@ -0,0 +1,52 @@
+/* Bump allocator on the initial memory pool.
+ *
+ * Temporary — until the PM-actor malloc path is implemented.
+ * Thread-safe: no — __libc.heap_used is guarded by nothing yet.
+ */
+
+#include <stddef.h>
+#include "libc.h"
+
+void *malloc(size_t size)
+{
+    if (size == 0) size = 1;
+
+    unsigned long heap = __libc.heap_base;
+    unsigned long used = __libc.heap_used;
+
+    if (used + size > __libc.heap_size)
+        return 0;
+
+    void *ptr = (void *)(heap + used);
+    __libc.heap_used = used + size;
+    return ptr;
+}
+
+void free(void *ptr)
+{
+    (void)ptr;
+}
+
+void *calloc(size_t nmemb, size_t size)
+{
+    size_t total = nmemb * size;
+    void *p = malloc(total);
+    if (!p) return 0;
+    for (size_t i = 0; i < total; i++)
+        ((unsigned char *)p)[i] = 0;
+    return p;
+}
+
+void *realloc(void *ptr, size_t size)
+{
+    if (!ptr) return malloc(size);
+    if (size == 0) { free(ptr); return 0; }
+    /* Bump allocator cannot shrink/grow in place — always allocate + copy */
+    void *newp = malloc(size);
+    if (!newp) return 0;
+    unsigned long old = __libc.heap_used - size;
+    if (old > __libc.heap_used) old = __libc.heap_used;
+    for (size_t i = 0; i < old; i++)
+        ((unsigned char *)newp)[i] = ((unsigned char *)ptr)[i];
+    return newp;
+}