Add custom pm sysmodule

sysmodules/pm/source/exheader_info_heap.c

@@ -0,0 +1,51 @@
+#include <3ds.h>
+#include <string.h>
+#include <stdatomic.h>
+
+typedef union Node {
+    union Node *next;
+    ExHeader_Info info;
+} Node;
+
+static Node *g_headNode = NULL;
+
+void ExHeaderInfoHeap_Init(void *buf, size_t num)
+{
+    Node *node = (Node *)buf;
+    g_headNode = node;
+    for (size_t i = 0; i < num; i++) {
+        node->next = &node[1];
+        node = node->next;
+    }
+}
+
+ExHeader_Info *ExHeaderInfoHeap_New(void)
+{
+    Node *newHead;
+    Node *oldHead = atomic_load(&g_headNode);
+    if (oldHead == NULL) {
+        return NULL;
+    } else {
+        do {
+            newHead = oldHead == NULL ? oldHead : oldHead->next;
+        } while(!atomic_compare_exchange_weak(&g_headNode, &oldHead, newHead));
+
+        if (oldHead == NULL) {
+            return NULL;
+        }
+        else {
+            memset(&oldHead->info, 0, sizeof(ExHeader_Info));
+            return &oldHead->info;
+        }
+    }
+}
+
+void ExHeaderInfoHeap_Delete(ExHeader_Info *data)
+{
+    Node *newHead = (Node *)data;
+    Node *oldHead = atomic_load(&g_headNode);
+    do {
+        newHead->next = oldHead;
+    } while(!atomic_compare_exchange_weak(&g_headNode, &oldHead, newHead));
+}
+