diff options
Diffstat (limited to '')
| -rw-r--r-- | lib/ngtcp2_gaptr.c | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/lib/ngtcp2_gaptr.c b/lib/ngtcp2_gaptr.c new file mode 100644 index 0000000..87c2389 --- /dev/null +++ b/lib/ngtcp2_gaptr.c @@ -0,0 +1,167 @@ +/* + * ngtcp2 + * + * Copyright (c) 2017 ngtcp2 contributors + * + * Permission is hereby granted, free of charge, to any person obtaining + * a copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE + * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION + * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION + * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +#include "ngtcp2_gaptr.h" + +#include <string.h> +#include <assert.h> + +void ngtcp2_gaptr_init(ngtcp2_gaptr *gaptr, const ngtcp2_mem *mem) { + ngtcp2_ksl_init(&gaptr->gap, ngtcp2_ksl_range_compar, sizeof(ngtcp2_range), + mem); + + gaptr->mem = mem; +} + +static int gaptr_gap_init(ngtcp2_gaptr *gaptr) { + ngtcp2_range range = {0, UINT64_MAX}; + int rv; + + rv = ngtcp2_ksl_insert(&gaptr->gap, NULL, &range, NULL); + if (rv != 0) { + return rv; + } + + return 0; +} + +void ngtcp2_gaptr_free(ngtcp2_gaptr *gaptr) { + if (gaptr == NULL) { + return; + } + + ngtcp2_ksl_free(&gaptr->gap); +} + +int ngtcp2_gaptr_push(ngtcp2_gaptr *gaptr, uint64_t offset, uint64_t datalen) { + int rv; + ngtcp2_range k, m, l, r, q = {offset, offset + datalen}; + ngtcp2_ksl_it it; + + if (ngtcp2_ksl_len(&gaptr->gap) == 0) { + rv = gaptr_gap_init(gaptr); + if (rv != 0) { + return rv; + } + } + + it = ngtcp2_ksl_lower_bound_compar(&gaptr->gap, &q, + ngtcp2_ksl_range_exclusive_compar); + + for (; !ngtcp2_ksl_it_end(&it);) { + k = *(ngtcp2_range *)ngtcp2_ksl_it_key(&it); + m = ngtcp2_range_intersect(&q, &k); + if (!ngtcp2_range_len(&m)) { + break; + } + + if (ngtcp2_range_eq(&k, &m)) { + ngtcp2_ksl_remove_hint(&gaptr->gap, &it, &it, &k); + continue; + } + ngtcp2_range_cut(&l, &r, &k, &m); + if (ngtcp2_range_len(&l)) { + ngtcp2_ksl_update_key(&gaptr->gap, &k, &l); + + if (ngtcp2_range_len(&r)) { + rv = ngtcp2_ksl_insert(&gaptr->gap, &it, &r, NULL); + if (rv != 0) { + return rv; + } + } + } else if (ngtcp2_range_len(&r)) { + ngtcp2_ksl_update_key(&gaptr->gap, &k, &r); + } + ngtcp2_ksl_it_next(&it); + } + return 0; +} + +uint64_t ngtcp2_gaptr_first_gap_offset(ngtcp2_gaptr *gaptr) { + ngtcp2_ksl_it it; + ngtcp2_range r; + + if (ngtcp2_ksl_len(&gaptr->gap) == 0) { + return 0; + } + + it = ngtcp2_ksl_begin(&gaptr->gap); + r = *(ngtcp2_range *)ngtcp2_ksl_it_key(&it); + + return r.begin; +} + +ngtcp2_range ngtcp2_gaptr_get_first_gap_after(ngtcp2_gaptr *gaptr, + uint64_t offset) { + ngtcp2_range q = {offset, offset + 1}; + ngtcp2_ksl_it it; + + if (ngtcp2_ksl_len(&gaptr->gap) == 0) { + ngtcp2_range r = {0, UINT64_MAX}; + return r; + } + + it = ngtcp2_ksl_lower_bound_compar(&gaptr->gap, &q, + ngtcp2_ksl_range_exclusive_compar); + + assert(!ngtcp2_ksl_it_end(&it)); + + return *(ngtcp2_range *)ngtcp2_ksl_it_key(&it); +} + +int ngtcp2_gaptr_is_pushed(ngtcp2_gaptr *gaptr, uint64_t offset, + uint64_t datalen) { + ngtcp2_range q = {offset, offset + datalen}; + ngtcp2_ksl_it it; + ngtcp2_range k; + ngtcp2_range m; + + if (ngtcp2_ksl_len(&gaptr->gap) == 0) { + return 0; + } + + it = ngtcp2_ksl_lower_bound_compar(&gaptr->gap, &q, + ngtcp2_ksl_range_exclusive_compar); + k = *(ngtcp2_range *)ngtcp2_ksl_it_key(&it); + m = ngtcp2_range_intersect(&q, &k); + + return ngtcp2_range_len(&m) == 0; +} + +void ngtcp2_gaptr_drop_first_gap(ngtcp2_gaptr *gaptr) { + ngtcp2_ksl_it it; + ngtcp2_range r; + + if (ngtcp2_ksl_len(&gaptr->gap) == 0) { + return; + } + + it = ngtcp2_ksl_begin(&gaptr->gap); + + assert(!ngtcp2_ksl_it_end(&it)); + + r = *(ngtcp2_range *)ngtcp2_ksl_it_key(&it); + + ngtcp2_ksl_remove_hint(&gaptr->gap, NULL, &it, &r); +} |