Fix vnet unit tests

[vpp.git] / src / vlib / buffer.h

diff --git a/src/vlib/buffer.h b/src/vlib/buffer.h
index 1f723f3..18e2437 100644 (file)
--- a/src/vlib/buffer.h
+++ b/src/vlib/buffer.h
@@ -205,6 +205,18 @@ vlib_buffer_advance (vlib_buffer_t * b, word l)
   b->current_length -= l;
 }
 
+/** \brief Check if there is enough space in buffer to advance
+
+    @param b - (vlib_buffer_t *) pointer to the buffer
+    @param l - (word) size to check
+    @return - 0 if there is less space than 'l' in buffer
+*/
+always_inline u8
+vlib_buffer_has_space (vlib_buffer_t * b, word l)
+{
+  return b->current_length >= l;
+}
+
 /** \brief Reset current header & length to state they were in when
     packet was received.
 
@@ -240,6 +252,74 @@ vlib_get_buffer_opaque2 (vlib_buffer_t * b)
   return (void *) b->opaque2;
 }
 
+/** \brief Get pointer to the end of buffer's data
+ * @param b     pointer to the buffer
+ * @return      pointer to tail of packet's data
+ */
+always_inline u8 *
+vlib_buffer_get_tail (vlib_buffer_t * b)
+{
+  return b->data + b->current_data + b->current_length;
+}
+
+/** \brief Append uninitialized data to buffer
+ * @param b     pointer to the buffer
+ * @param size  number of uninitialized bytes
+ * @return      pointer to beginning of uninitialized data
+ */
+always_inline void *
+vlib_buffer_put_uninit (vlib_buffer_t * b, u8 size)
+{
+  void *p = vlib_buffer_get_tail (b);
+  /* XXX make sure there's enough space */
+  b->current_length += size;
+  return p;
+}
+
+/** \brief Prepend uninitialized data to buffer
+ * @param b     pointer to the buffer
+ * @param size  number of uninitialized bytes
+ * @return      pointer to beginning of uninitialized data
+ */
+always_inline void *
+vlib_buffer_push_uninit (vlib_buffer_t * b, u8 size)
+{
+  ASSERT (b->current_data + VLIB_BUFFER_PRE_DATA_SIZE >= size);
+  b->current_data -= size;
+  b->current_length += size;
+
+  return vlib_buffer_get_current (b);
+}
+
+/** \brief Make head room, typically for packet headers
+ * @param b     pointer to the buffer
+ * @param size  number of head room bytes
+ * @return      pointer to start of buffer (current data)
+ */
+always_inline void *
+vlib_buffer_make_headroom (vlib_buffer_t * b, u8 size)
+{
+  ASSERT (b->current_data + VLIB_BUFFER_PRE_DATA_SIZE >= size);
+  b->current_data += size;
+  return vlib_buffer_get_current (b);
+}
+
+/** \brief Retrieve bytes from buffer head
+ * @param b     pointer to the buffer
+ * @param size  number of bytes to pull
+ * @return      pointer to start of buffer (current data)
+ */
+always_inline void *
+vlib_buffer_pull (vlib_buffer_t * b, u8 size)
+{
+  if (b->current_length + VLIB_BUFFER_PRE_DATA_SIZE < size)
+    return 0;
+
+  void *data = vlib_buffer_get_current (b);
+  vlib_buffer_advance (b, size);
+  return data;
+}
+
 /* Forward declaration. */
 struct vlib_main_t;