add vec

1 files changed, 23 insertions, 0 deletions

diff --git a/lib/cbit/vec.c b/lib/cbit/vec.c
new file mode 100644
index 0000000..21038a2
--- /dev/null
+++ b/lib/cbit/vec.c
@@ -0,0 +1,23 @@
+#include "cbit/vec.h"
+#include <stdio.h>
+
+void vec_realloc_internal(struct vec_internal *vi, size_t new_capacity,
+                          size_t esize) {
+    size_t new_size = safe_mul(new_capacity, esize);
+    if (vi->els == vi->storage) {
+        void *new = malloc(new_size);
+        memcpy(new, vi->els, vi->capacity * esize);
+        vi->els = new;
+    } else {
+        vi->els = realloc(vi->els, new_size);
+    }
+    vi->capacity = new_capacity;
+}
+void vec_realloc_internal_as_necessary(struct vec_internal *vi,
+                                       size_t min_capacity,
+                                       size_t esize) {
+    if (min_capacity > vi->capacity)
+        vec_realloc_internal(vi, safe_mul(vi->capacity, 2), esize);
+    else if (min_capacity < vi->capacity / 3)
+        vec_realloc_internal(vi, vi->capacity / 3, esize);
+}