1 files changed, 45 insertions, 0 deletions
diff --git a/src/nvim/rbuffer_defs.h b/src/nvim/rbuffer_defs.h
new file mode 100644
index 0000000000..51dc349846
--- /dev/null
+++ b/src/nvim/rbuffer_defs.h
@@ -0,0 +1,45 @@
+#pragma once
+
+#include <stddef.h>
+
+#include "nvim/func_attr.h"
+
+typedef struct rbuffer RBuffer;
+/// Type of function invoked during certain events:
+///   - When the RBuffer switches to the full state
+///   - When the RBuffer switches to the non-full state
+typedef void (*rbuffer_callback)(RBuffer *buf, void *data);
+
+struct rbuffer {
+  rbuffer_callback full_cb, nonfull_cb;
+  void *data;
+  size_t size;
+  // helper memory used to by rbuffer_reset if required
+  char *temp;
+  char *end_ptr, *read_ptr, *write_ptr;
+  char start_ptr[];
+};
+
+static inline size_t rbuffer_size(RBuffer *buf)
+  REAL_FATTR_ALWAYS_INLINE REAL_FATTR_NONNULL_ALL;
+
+static inline size_t rbuffer_size(RBuffer *buf)
+{
+  return buf->size;
+}
+
+static inline size_t rbuffer_capacity(RBuffer *buf)
+  REAL_FATTR_ALWAYS_INLINE REAL_FATTR_NONNULL_ALL;
+
+static inline size_t rbuffer_capacity(RBuffer *buf)
+{
+  return (size_t)(buf->end_ptr - buf->start_ptr);
+}
+
+static inline size_t rbuffer_space(RBuffer *buf)
+  REAL_FATTR_ALWAYS_INLINE REAL_FATTR_NONNULL_ALL;
+
+static inline size_t rbuffer_space(RBuffer *buf)
+{
+  return rbuffer_capacity(buf) - buf->size;
+}