udp/session: refactor to support dgram mode

[vpp.git] / src / svm / svm_fifo.c

diff --git a/src/svm/svm_fifo.c b/src/svm/svm_fifo.c
index 42eb1ee..3552192 100644 (file)
--- a/src/svm/svm_fifo.c
+++ b/src/svm/svm_fifo.c
@@ -169,6 +169,9 @@ format_svm_fifo (u8 * s, va_list * args)
   svm_fifo_t *f = va_arg (*args, svm_fifo_t *);
   int verbose = va_arg (*args, int);
 
+  if (!s)
+    return s;
+
   s = format (s, "cursize %u nitems %u has_event %d\n",
              f->cursize, f->nitems, f->has_event);
   s = format (s, " head %d tail %d\n", f->head, f->tail);
@@ -448,7 +451,8 @@ ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued)
 }
 
 static int
-svm_fifo_enqueue_internal (svm_fifo_t * f, u32 max_bytes, u8 * copy_from_here)
+svm_fifo_enqueue_internal (svm_fifo_t * f, u32 max_bytes,
+                          const u8 * copy_from_here)
 {
   u32 total_copy_bytes, first_copy_bytes, second_copy_bytes;
   u32 cursize, nitems;
@@ -458,7 +462,7 @@ svm_fifo_enqueue_internal (svm_fifo_t * f, u32 max_bytes, u8 * copy_from_here)
   f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
 
   if (PREDICT_FALSE (cursize == f->nitems))
-    return -2;                 /* fifo stuffed */
+    return SVM_FIFO_FULL;
 
   nitems = f->nitems;
 
@@ -520,7 +524,7 @@ svm_fifo_enqueue_internal (svm_fifo_t * f, u32 max_bytes, u8 * copy_from_here)
 
 static int
 svm_fifo_enqueue_nowait_ma (svm_fifo_t * f, u32 max_bytes,
-                           u8 * copy_from_here)
+                           const u8 * copy_from_here)
 {
   return svm_fifo_enqueue_internal (f, max_bytes, copy_from_here);
 }
@@ -530,12 +534,13 @@ foreach_march_variant (SVM_ENQUEUE_CLONE_TEMPLATE,
 CLIB_MULTIARCH_SELECT_FN (svm_fifo_enqueue_nowait_ma);
 
 int
-svm_fifo_enqueue_nowait (svm_fifo_t * f, u32 max_bytes, u8 * copy_from_here)
+svm_fifo_enqueue_nowait (svm_fifo_t * f, u32 max_bytes,
+                        const u8 * copy_from_here)
 {
 #if CLIB_DEBUG > 0
   return svm_fifo_enqueue_nowait_ma (f, max_bytes, copy_from_here);
 #else
-  static int (*fp) (svm_fifo_t *, u32, u8 *);
+  static int (*fp) (svm_fifo_t *, u32, const u8 *);
 
   if (PREDICT_FALSE (fp == 0))
     fp = (void *) svm_fifo_enqueue_nowait_ma_multiarch_select ();
@@ -613,6 +618,20 @@ svm_fifo_enqueue_with_offset (svm_fifo_t * f,
                                                copy_from_here);
 }
 
+void
+svm_fifo_overwrite_head (svm_fifo_t * f, u8 * data, u32 len)
+{
+  u32 first_chunk;
+  ASSERT (len <= f->nitems);
+  if (len < f->nitems - f->head)
+    clib_memcpy (&f->data[f->head], data, len);
+  else
+    {
+      first_chunk = len - (f->nitems - f->head);
+      clib_memcpy (&f->data[f->head], data, first_chunk);
+      clib_memcpy (f->data, data + first_chunk, len - first_chunk);
+    }
+}
 
 static int
 svm_fifo_dequeue_internal (svm_fifo_t * f, u32 max_bytes, u8 * copy_here)