1 files changed, 55 insertions, 8 deletions
diff --git a/src/user/include/cxx/structs/alist.h b/src/user/include/cxx/structs/alist.h
index 050f775..13a24c4 100644
--- a/src/user/include/cxx/structs/alist.h
+++ b/src/user/include/cxx/structs/alist.h
@@ -15,20 +15,67 @@ public:
   uint32_t expand_by;
   data *buf;
 
-  alist(uint32_t default_size=10, uint32_t expand_by=10)
+  alist(uint32_t default_size = 10, uint32_t expand_by = 10)
     : n_entries(0), buf_size(default_size), expand_by(expand_by),
-      buf((data *)get_block(default_size * sizeof(data))) {}
+      buf(new data[default_size]) {}
+
+  //from is copied
+  alist(const data *from, uint32_t count, uint32_t extra_size = 10, uint32_t expand_by = 10)
+    : n_entries(count), buf_size(count + extra_size), expand_by(expand_by),
+      buf(new data[count + extra_size]) {
+    for (uint32_t i = 0; i < count; ++i)
+      buf[i] = from[i];
+  }
+
+  ~alist() {
+    delete[] buf;
+  }
+
+  void copy_from(const data *from, uint32_t count) {
+    expand_to(count);
+    n_entries = count;
+    for (uint32_t i = 0; i < count; ++i)
+      buf[i] = from[i];
+  }
+
+  void expand_to(uint32_t size) {
+    if (size <= buf_size)
+      return;
+    data *const new_buf = new data[size * sizeof(data)];
+    for (uint32_t i = 0; i < buf_size; ++i)
+      new_buf[i] = buf[i];
+    delete[] buf;
+    buf = new_buf;
+    buf_size = size;
+  }
+
+  void copy_from(const alist<data> &other) {
+    expand_to(n_entries = other.n_entries);
+    for (uint32_t i = 0; i < n_entries; ++i)
+      buf[i] = other.buf[i];
+  }
 
   void add_back(data d) {
-    if (n_entries == buf_size) {
-      data *const new_buf = (data *)get_block((buf_size += expand_by) * sizeof(data));
-      blockcpy(new_buf, buf, n_entries * sizeof(data));
-      free_block(buf);
-      buf = new_buf;
-    }
+    if (n_entries == buf_size)
+      expand_to(buf_size + expand_by);
     buf[n_entries++] = d;
   }
 
+  void insert(uint32_t i, data d) {
+    if (n_entries == buf_size)
+      expand_to(buf_size + expand_by);
+    for (uint32_t n = n_entries; n > i; --n)
+      buf[n] = buf[n - 1];
+    buf[i] = d;
+    ++n_entries;
+  }
+
+  void remove(uint32_t i) {
+    --n_entries;
+    for (uint32_t n = i; n < n_entries; ++n)
+      buf[n] = buf[n + 1];
+  }
+
   //returns -1 if not found
   uint32_t index_of(data d) {
     for (uint32_t i = 0; i < n_entries; ++i)