c-ares / c-ares / 28591205316

90%

Build Type

push

github

Committed by web-flow

Commit Message

ares_array: reset offset when array becomes empty (#1165)

ares_array_claim_at() removes the first element in O(1) by advancing
arr->offset instead of shifting. If every element is claimed from the
front, offset can climb to arr->alloc_cnt. Reusing the array afterwards
(appending while draining from the front) then made
ares_array_insert_at() compact via ares_array_move() with an
out-of-range source index, failing with ARES_EFORMERR.

Reset offset to 0 once the array is empty. There is nothing to preserve,
and this is provably the only case ares_array_move() could fail: the
invariant offset + cnt <= alloc_cnt holds everywhere, so offset can only
reach alloc_cnt when cnt == 0.

Add a regression test exercising interleaved front-claim and append.

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Signed-off-by: David Hotham (@dimbleby)

Coverage Stats

24 of 24 new or added lines in 2 files covered. (100.0%)

1 existing line in 1 file now uncovered.

23044 of 25126 relevant lines covered (91.71%)

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