[4/6] incubator-mynewt-core git commit: mempool - Allow mempool with 0 blocks.

[cc...@apache.org]

mempool - Allow mempool with 0 blocks.

This is useful in cases when the mempool is sized according to an
application setting.  If the user wants 0 of something, it is easier to
just initialize the mempool with 0 blocks and a NULL buffer, and just
let any attempt to allocate from it to fail.


Project: http://git-wip-us.apache.org/repos/asf/incubator-mynewt-core/repo
Commit: http://git-wip-us.apache.org/repos/asf/incubator-mynewt-core/commit/9d5aa01d
Tree: http://git-wip-us.apache.org/repos/asf/incubator-mynewt-core/tree/9d5aa01d
Diff: http://git-wip-us.apache.org/repos/asf/incubator-mynewt-core/diff/9d5aa01d

Branch: refs/heads/develop
Commit: 9d5aa01d3e1e46a4a78365c45680c8693747235c
Parents: 4965b05
Author: Christopher Collins <cc...@apache.org>
Authored: Thu Aug 4 16:24:47 2016 -0700
Committer: Christopher Collins <cc...@apache.org>
Committed: Thu Aug 4 16:24:47 2016 -0700

----------------------------------------------------------------------
 libs/os/src/os_mempool.c | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/incubator-mynewt-core/blob/9d5aa01d/libs/os/src/os_mempool.c
----------------------------------------------------------------------
diff --git a/libs/os/src/os_mempool.c b/libs/os/src/os_mempool.c
index 04a18a1..e940ba4 100644
--- a/libs/os/src/os_mempool.c
+++ b/libs/os/src/os_mempool.c
@@ -41,21 +41,29 @@ STAILQ_HEAD(, os_mempool) g_os_mempool_list =
  * @return os_error_t 
  */
 os_error_t
-os_mempool_init(struct os_mempool *mp, int blocks, int block_size, void *membuf,
-                char *name)
+os_mempool_init(struct os_mempool *mp, int blocks, int block_size,
+                void *membuf, char *name)
 {
     int true_block_size;
     uint8_t *block_addr;
     struct os_memblock *block_ptr;
 
     /* Check for valid parameters */
-    if ((!mp) || (!membuf) || (blocks <= 0) || (block_size <= 0)) {
+    if ((!mp) || (blocks < 0) || (block_size <= 0)) {
         return OS_INVALID_PARM;
     }
 
-    /* Blocks need to be sized properly and memory buffer should be aligned */
-    if (((uint32_t)membuf & (OS_ALIGNMENT - 1)) != 0) {
-        return OS_MEM_NOT_ALIGNED;
+    if ((!membuf) && (blocks != 0)) {
+        return OS_INVALID_PARM;
+    }
+
+    if (membuf != NULL) {
+        /* Blocks need to be sized properly and memory buffer should be
+         * aligned
+         */
+        if (((uint32_t)membuf & (OS_ALIGNMENT - 1)) != 0) {
+            return OS_MEM_NOT_ALIGNED;
+        }
     }
     true_block_size = OS_MEMPOOL_TRUE_BLOCK_SIZE(block_size);