Improve fifo allocator performance

- add option to preallocate fifos in a segment
- track active fifos with doubly linked list instead of vector
- update udp redirect test code to read fifo pointers from API call
  instead of digging them up from fifo segment header
- input-node based active-open session generator

Change-Id: I804b81e99d95f8690d17e12660c6645995e28a9a
Signed-off-by: Dave Barach <dave@barachs.net>
Signed-off-by: Florin Coras <fcoras@cisco.com>
Signed-off-by: Dave Barach <dbarach@cisco.com>
diff --git a/src/uri/uri_tcp_test.c b/src/uri/uri_tcp_test.c
index 22f246e..e201a35 100755
--- a/src/uri/uri_tcp_test.c
+++ b/src/uri/uri_tcp_test.c
@@ -193,6 +193,7 @@
   bmp->context = ntohl (0xfeedface);
   bmp->options[APP_OPTIONS_FLAGS] =
     APP_OPTIONS_FLAGS_USE_FIFO | APP_OPTIONS_FLAGS_ADD_SEGMENT;
+  bmp->options[APP_OPTIONS_PREALLOC_FIFO_PAIRS] = 16;
   bmp->options[SESSION_OPTIONS_RX_FIFO_SIZE] = fifo_size;
   bmp->options[SESSION_OPTIONS_TX_FIFO_SIZE] = fifo_size;
   bmp->options[SESSION_OPTIONS_ADD_SEGMENT_SIZE] = 128 << 20;