From 68b0fb0c620c7451ef1a6380c43c39de6614db51 Mon Sep 17 00:00:00 2001 From: Dave Barach Date: Tue, 28 Feb 2017 15:15:56 -0500 Subject: VPP-598: tcp stack initial commit Change-Id: I49e5ce0aae6e4ff634024387ceaf7dbc432a0351 Signed-off-by: Dave Barach Signed-off-by: Florin Coras --- src/vlib/buffer.h | 68 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+) (limited to 'src/vlib/buffer.h') diff --git a/src/vlib/buffer.h b/src/vlib/buffer.h index 1f723f3b..69c8c7cc 100644 --- a/src/vlib/buffer.h +++ b/src/vlib/buffer.h @@ -240,6 +240,74 @@ 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; -- cgit 1.2.3-korg