Sometimes it is useful to empty the list without de-allocating any of the memory used, e.g. when the list will be re-populated immediately afterwards.
Add a new function for this.
Signed-off-by: Simon Glass sjg@chromium.org ---
include/alist.h | 7 +++++++ lib/alist.c | 5 +++++ test/lib/alist.c | 42 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 54 insertions(+)
diff --git a/include/alist.h b/include/alist.h index 0090b9c0eb1..c639e42ab7d 100644 --- a/include/alist.h +++ b/include/alist.h @@ -274,6 +274,13 @@ bool alist_chk_ptr(const struct alist *lst, const void *ptr); _pos < alist_end(_lst, typeof(*(_pos))); \ _pos++)
+/** + * alist_empty() - Empty an alist + * + * This removes all entries from the list, without changing the allocated size + */ +void alist_empty(struct alist *lst); + /** * alist_init() - Set up a new object list * diff --git a/lib/alist.c b/lib/alist.c index 1a4b4fb9c40..32cd45b0b01 100644 --- a/lib/alist.c +++ b/lib/alist.c @@ -41,6 +41,11 @@ void alist_uninit(struct alist *lst) memset(lst, '\0', sizeof(struct alist)); }
+void alist_empty(struct alist *lst) +{ + lst->count = 0; +} + /** * alist_expand_to() - Expand a list to the given size * diff --git a/test/lib/alist.c b/test/lib/alist.c index 1715a22584c..87135bb3a51 100644 --- a/test/lib/alist.c +++ b/test/lib/alist.c @@ -358,6 +358,16 @@ static int lib_test_alist_for_each(struct unit_test_state *uts) ptr = lst.data; ut_asserteq_ptr(ptr + 3, alist_end(&lst, struct my_struct));
+ /* empty the list and try again */ + alist_empty(&lst); + ut_asserteq_ptr(ptr, alist_end(&lst, struct my_struct)); + ut_assertnull(alist_get(&lst, 0, struct my_struct)); + + sum = 0; + alist_for_each(ptr, &lst) + sum += ptr->val; + ut_asserteq(0, sum); + alist_uninit(&lst);
/* Check for memory leaks */ @@ -366,3 +376,35 @@ static int lib_test_alist_for_each(struct unit_test_state *uts) return 0; } LIB_TEST(lib_test_alist_for_each, 0); + +/* Test alist_empty() */ +static int lib_test_alist_empty(struct unit_test_state *uts) +{ + struct my_struct data; + struct alist lst; + ulong start; + + start = ut_check_free(); + + ut_assert(alist_init_struct(&lst, struct my_struct)); + ut_asserteq(0, lst.count); + data.val = 1; + data.other_val = 0; + alist_add(&lst, data); + ut_asserteq(1, lst.count); + ut_asserteq(4, lst.alloc); + + alist_empty(&lst); + ut_asserteq(0, lst.count); + ut_asserteq(4, lst.alloc); + ut_assertnonnull(lst.data); + ut_asserteq(sizeof(data), lst.obj_size); + + alist_uninit(&lst); + + /* Check for memory leaks */ + ut_assertok(ut_check_delta(start)); + + return 0; +} +LIB_TEST(lib_test_alist_empty, 0);