diff options
| author | Ha Thach <[email protected]> | 2021-07-01 02:25:23 +0700 |
|---|---|---|
| committer | GitHub <[email protected]> | 2021-07-01 02:25:23 +0700 |
| commit | 9b3ec69b27b5d18d4c1f34d6730cec21afc8e628 (patch) | |
| tree | a6e544264d7cf411ae244f1dde07da3f5dad48a9 | |
| parent | 3b539fdd8d8e9d48756cf5f6e0d605af3972651c (diff) | |
| parent | 74b51d43e1e8e14def49c140f8f063eb56c9e4d2 (diff) | |
Merge pull request #940 from HiFiPhile/fifo_fix
Fix fifo overflow correction.
| -rw-r--r-- | src/common/tusb_fifo.c | 4 | ||||
| -rw-r--r-- | test/test/test_fifo.c | 24 |
2 files changed, 26 insertions, 2 deletions
diff --git a/src/common/tusb_fifo.c b/src/common/tusb_fifo.c index 1eb886aa1..73217cf75 100644 --- a/src/common/tusb_fifo.c +++ b/src/common/tusb_fifo.c @@ -325,7 +325,7 @@ static uint16_t advance_pointer(tu_fifo_t* f, uint16_t p, uint16_t offset) // We are exploiting the wrap around to the correct index // TODO warning: assuming signed overflow does not occur when assuming that (X + c) < X is always false [-Wstrict-overflow] - if ((p > p + offset) || (p + offset > f->max_pointer_idx)) + if ((p > (uint16_t)(p + offset)) || ((uint16_t)(p + offset) > f->max_pointer_idx)) { p = (p + offset) + f->non_used_index_space; } @@ -342,7 +342,7 @@ static uint16_t backward_pointer(tu_fifo_t* f, uint16_t p, uint16_t offset) // We limit the index space of p such that a correct wrap around happens // Check for a wrap around or if we are in unused index space - This has to be checked first!! // We are exploiting the wrap around to the correct index - if ((p < p - offset) || (p - offset > f->max_pointer_idx)) + if ((p < (uint16_t)(p - offset)) || ((uint16_t)(p - offset) > f->max_pointer_idx)) { p = (p - offset) - f->non_used_index_space; } diff --git a/test/test/test_fifo.c b/test/test/test_fifo.c index f9bfc5f03..0a5f4d3b9 100644 --- a/test/test/test_fifo.c +++ b/test/test/test_fifo.c @@ -292,3 +292,27 @@ void test_full(void) // write info } + +void test_rd_idx_wrap() +{ + tu_fifo_t ff10; + uint8_t buf[10]; + uint8_t dst[10]; + + tu_fifo_config(&ff10, buf, 10, 1, 1); + + uint16_t n; + + ff10.wr_idx = 6; + ff10.rd_idx = 15; + + n = tu_fifo_read_n(&ff10, dst, 4); + TEST_ASSERT_EQUAL(n, 4); + TEST_ASSERT_EQUAL(ff10.rd_idx, 0); + n = tu_fifo_read_n(&ff10, dst, 4); + TEST_ASSERT_EQUAL(n, 4); + TEST_ASSERT_EQUAL(ff10.rd_idx, 4); + n = tu_fifo_read_n(&ff10, dst, 4); + TEST_ASSERT_EQUAL(n, 2); + TEST_ASSERT_EQUAL(ff10.rd_idx, 6); +}
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