From 2f763887b8696f2fd2d577bfbd011f3b2e889c1a Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Wed, 9 Dec 2015 18:05:53 +0100 Subject: [PATCH] resolved: grow DnsAnswer exponentially When increasing the DnsAnswer array, don't operate piecemeal, grow the array exponentially. This way, the default logic for DnsAnswer allocations matches the behaviour for GREEDY_REALLOC and suchlike, and we can reduce the number of necessary allocations. --- src/resolve/resolved-dns-answer.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/src/resolve/resolved-dns-answer.c b/src/resolve/resolved-dns-answer.c index f1f4d90..92b9871 100644 --- a/src/resolve/resolved-dns-answer.c +++ b/src/resolve/resolved-dns-answer.c @@ -271,6 +271,8 @@ void dns_answer_order_by_scope(DnsAnswer *a, bool prefer_link_local) { int dns_answer_reserve(DnsAnswer **a, unsigned n_free) { DnsAnswer *n; + assert(a); + if (n_free <= 0) return 0; @@ -285,6 +287,9 @@ int dns_answer_reserve(DnsAnswer **a, unsigned n_free) { if ((*a)->n_allocated >= ns) return 0; + /* Allocate more than we need */ + ns *= 2; + n = realloc(*a, offsetof(DnsAnswer, items) + sizeof(DnsAnswerItem) * ns); if (!n) return -ENOMEM; -- 2.7.4