diff options
Diffstat (limited to 'src/lib/smartlist_core/smartlist_core.c')
| -rw-r--r-- | src/lib/smartlist_core/smartlist_core.c | 28 |
1 files changed, 27 insertions, 1 deletions
diff --git a/src/lib/smartlist_core/smartlist_core.c b/src/lib/smartlist_core/smartlist_core.c index ac85a6cc84..571d17aa5d 100644 --- a/src/lib/smartlist_core/smartlist_core.c +++ b/src/lib/smartlist_core/smartlist_core.c @@ -1,6 +1,6 @@ /* Copyright (c) 2003-2004, Roger Dingledine * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. - * Copyright (c) 2007-2019, The Tor Project, Inc. */ + * Copyright (c) 2007-2020, The Tor Project, Inc. */ /* See LICENSE for licensing information */ /** @@ -88,6 +88,30 @@ smartlist_ensure_capacity(smartlist_t *sl, size_t size) #undef MAX_CAPACITY } +/** Expand <b>sl</b> so that its length is at least <b>new_size</b>, + * filling in previously unused entries with NULL> + * + * Do nothing if <b>sl</b> already had at least <b>new_size</b> elements. + */ +void +smartlist_grow(smartlist_t *sl, size_t new_size) +{ + smartlist_ensure_capacity(sl, new_size); + + if (new_size > (size_t)sl->num_used) { + /* This memset() should be a no-op: everything else in the smartlist code + * tries to make sure that unused entries are always NULL. Still, that is + * meant as a safety mechanism, so let's clear the memory here. + */ + memset(sl->list + sl->num_used, 0, + sizeof(void *) * (new_size - sl->num_used)); + + /* This cast is safe, since we already asserted that we were below + * MAX_CAPACITY in smartlist_ensure_capacity(). */ + sl->num_used = (int)new_size; + } +} + /** Append element to the end of the list. */ void smartlist_add(smartlist_t *sl, void *element) @@ -153,6 +177,8 @@ smartlist_remove_keeporder(smartlist_t *sl, const void *element) sl->list[i++] = sl->list[j]; } } + memset(sl->list + sl->num_used, 0, + sizeof(void *) * (num_used_orig - sl->num_used)); } /** If <b>sl</b> is nonempty, remove and return the final element. Otherwise, |