From 5fa8cda981940eaef54b55abe4fcba09b4e18e12 Mon Sep 17 00:00:00 2001
From: Russell Belfer <rb@github.com>
Date: Mon, 30 Jun 2014 12:05:25 -0700
Subject: [PATCH] Round up pool alloc sizes for alignment

To make sure that items returned from pool allocations are aligned
on nice boundaries, this rounds up all pool allocation sizes to a
multiple of 8.  This adds a small amount of overhead to each item.

The rounding up could be made optional with an extra parameter to
the pool initialization that turned on rounding only for pools
where item alignment actually matters, but I think for the extra
code and complexity that would be involved, that it makes sense
just to burn a little bit of extra memory and enable this all the
time.
---
 src/pool.c        |  2 +-
 tests/core/pool.c | 10 +++++-----
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/pool.c b/src/pool.c
index 146f118..a516ff9 100644
--- a/src/pool.c
+++ b/src/pool.c
@@ -146,7 +146,7 @@ GIT_INLINE(void) pool_remove_page(
 void *git_pool_malloc(git_pool *pool, uint32_t items)
 {
 	git_pool_page *scan = pool->open, *prev;
-	uint32_t size = items * pool->item_size;
+	uint32_t size = ((items * pool->item_size) + 7) & ~7;
 	void *ptr = NULL;
 
 	pool->has_string_alloc = 0;
diff --git a/tests/core/pool.c b/tests/core/pool.c
index 351d0c2..a7ec880 100644
--- a/tests/core/pool.c
+++ b/tests/core/pool.c
@@ -38,19 +38,19 @@ void test_core_pool__1(void)
 		cl_assert(git_pool_malloc(&p, i) != NULL);
 
 	/* with fixed page size, allocation must end up with these values */
-	cl_assert(git_pool__open_pages(&p) == 1);
-	cl_assert(git_pool__full_pages(&p) == 505);
+	cl_assert_equal_i(1, git_pool__open_pages(&p));
+	cl_assert_equal_i(507, git_pool__full_pages(&p));
 
 	git_pool_clear(&p);
 
-	cl_git_pass(git_pool_init(&p, 1, 4100));
+	cl_git_pass(git_pool_init(&p, 1, 4120));
 
 	for (i = 2010; i > 0; i--)
 		cl_assert(git_pool_malloc(&p, i) != NULL);
 
 	/* with fixed page size, allocation must end up with these values */
-	cl_assert(git_pool__open_pages(&p) == 1);
-	cl_assert(git_pool__full_pages(&p) == 492);
+	cl_assert_equal_i(1, git_pool__open_pages(&p));
+	cl_assert_equal_i(492, git_pool__full_pages(&p));
 
 	git_pool_clear(&p);
 }
-- 
1.9.3