From 10b6e58f2cb402bb074033ac3e85c98272a88e12 Mon Sep 17 00:00:00 2001
From: skarg <skarg@1e814d3a-8a88-4260-be86-c0dc25669c1e>
Date: Fri, 6 Jan 2012 18:52:44 +0000
Subject: [PATCH] Improved FIFO_Available by allowing the last byte to be
 available.

---
 bacnet-stack/include/fifo.h |  4 ++++
 bacnet-stack/src/fifo.c     | 12 ++++++++++--
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/bacnet-stack/include/fifo.h b/bacnet-stack/include/fifo.h
index 4a4a4333..93ac616f 100755
--- a/bacnet-stack/include/fifo.h
+++ b/bacnet-stack/include/fifo.h
@@ -63,6 +63,10 @@ extern "C" {
     bool FIFO_Full(
         FIFO_BUFFER const *b);
 
+    bool FIFO_Available (
+        FIFO_BUFFER const *b,
+        unsigned count);
+
     bool FIFO_Empty(
         FIFO_BUFFER const *b);
 
diff --git a/bacnet-stack/src/fifo.c b/bacnet-stack/src/fifo.c
index ae737dd5..5a95d949 100755
--- a/bacnet-stack/src/fifo.c
+++ b/bacnet-stack/src/fifo.c
@@ -81,11 +81,11 @@ bool FIFO_Full(
 * ALGORITHM:   none
 * NOTES:       none
 *****************************************************************************/
-static bool FIFO_Available(
+bool FIFO_Available(
     FIFO_BUFFER const *b,
     unsigned count)
 {
-    return (b ? (count < (b->buffer_len - FIFO_Count(b))) : false);
+    return (b ? (count <= (b->buffer_len - FIFO_Count(b))) : false);
 }
 
 /****************************************************************************
@@ -245,11 +245,15 @@ void testFIFOBuffer(
 
     /* load the buffer */
     for (test_data = 0; test_data < FIFO_BUFFER_SIZE; test_data++) {
+        ct_test(pTest, !FIFO_Full(&test_buffer));
+        ct_test(pTest, FIFO_Available(&test_buffer, 1));
         status = FIFO_Put(&test_buffer, test_data);
         ct_test(pTest, status == true);
         ct_test(pTest, !FIFO_Empty(&test_buffer));
     }
     /* not able to put any more */
+    ct_test(pTest, FIFO_Full(&test_buffer));
+    ct_test(pTest, !FIFO_Available(&test_buffer, 1));
     status = FIFO_Put(&test_buffer, 42);
     ct_test(pTest, status == false);
     /* unload the buffer */
@@ -259,6 +263,8 @@ void testFIFOBuffer(
         ct_test(pTest, test_data == index);
         test_data = FIFO_Get(&test_buffer);
         ct_test(pTest, test_data == index);
+        ct_test(pTest, FIFO_Available(&test_buffer, 1));
+        ct_test(pTest, !FIFO_Full(&test_buffer));
     }
     ct_test(pTest, FIFO_Empty(&test_buffer));
     test_data = FIFO_Get(&test_buffer);
@@ -269,6 +275,7 @@ void testFIFOBuffer(
     /* test the ring around the buffer */
     for (index = 0; index < FIFO_BUFFER_SIZE; index++) {
         ct_test(pTest, FIFO_Empty(&test_buffer));
+        ct_test(pTest, FIFO_Available(&test_buffer, 4));
         for (count = 1; count < 4; count++) {
             test_data = count;
             status = FIFO_Put(&test_buffer, test_data);
@@ -285,6 +292,7 @@ void testFIFOBuffer(
     }
     ct_test(pTest, FIFO_Empty(&test_buffer));
     /* test Add */
+    ct_test(pTest, FIFO_Available(&test_buffer, sizeof(test_add_data)));
     status = FIFO_Add(&test_buffer, test_add_data, sizeof(test_add_data));
     ct_test(pTest, status == true);
     ct_test(pTest, !FIFO_Empty(&test_buffer));