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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 07:32:08 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 07:32:08 +0000 |
commit | 328ad0a41c6bdf596224ff2e9ab9c0fabde8634d (patch) | |
tree | 973585a56cea8664b4be63b5bb737b443e4e2b76 /lib/nghttp3_pq.c | |
parent | Initial commit. (diff) | |
download | nghttp3-upstream.tar.xz nghttp3-upstream.zip |
Adding upstream version 0.8.0.upstream/0.8.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | lib/nghttp3_pq.c | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/lib/nghttp3_pq.c b/lib/nghttp3_pq.c new file mode 100644 index 0000000..5d09050 --- /dev/null +++ b/lib/nghttp3_pq.c @@ -0,0 +1,168 @@ +/* + * nghttp3 + * + * Copyright (c) 2019 nghttp3 contributors + * Copyright (c) 2017 ngtcp2 contributors + * Copyright (c) 2012 nghttp2 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 "nghttp3_pq.h" + +#include <assert.h> + +#include "nghttp3_macro.h" + +void nghttp3_pq_init(nghttp3_pq *pq, nghttp3_less less, + const nghttp3_mem *mem) { + pq->mem = mem; + pq->capacity = 0; + pq->q = NULL; + pq->length = 0; + pq->less = less; +} + +void nghttp3_pq_free(nghttp3_pq *pq) { + nghttp3_mem_free(pq->mem, pq->q); + pq->q = NULL; +} + +static void swap(nghttp3_pq *pq, size_t i, size_t j) { + nghttp3_pq_entry *a = pq->q[i]; + nghttp3_pq_entry *b = pq->q[j]; + + pq->q[i] = b; + b->index = i; + pq->q[j] = a; + a->index = j; +} + +static void bubble_up(nghttp3_pq *pq, size_t index) { + size_t parent; + while (index != 0) { + parent = (index - 1) / 2; + if (!pq->less(pq->q[index], pq->q[parent])) { + return; + } + swap(pq, parent, index); + index = parent; + } +} + +int nghttp3_pq_push(nghttp3_pq *pq, nghttp3_pq_entry *item) { + if (pq->capacity <= pq->length) { + void *nq; + size_t ncapacity; + + ncapacity = nghttp3_max(4, (pq->capacity * 2)); + + nq = nghttp3_mem_realloc(pq->mem, pq->q, + ncapacity * sizeof(nghttp3_pq_entry *)); + if (nq == NULL) { + return NGHTTP3_ERR_NOMEM; + } + pq->capacity = ncapacity; + pq->q = nq; + } + pq->q[pq->length] = item; + item->index = pq->length; + ++pq->length; + bubble_up(pq, pq->length - 1); + return 0; +} + +nghttp3_pq_entry *nghttp3_pq_top(const nghttp3_pq *pq) { + assert(pq->length); + return pq->q[0]; +} + +static void bubble_down(nghttp3_pq *pq, size_t index) { + size_t i, j, minindex; + for (;;) { + j = index * 2 + 1; + minindex = index; + for (i = 0; i < 2; ++i, ++j) { + if (j >= pq->length) { + break; + } + if (pq->less(pq->q[j], pq->q[minindex])) { + minindex = j; + } + } + if (minindex == index) { + return; + } + swap(pq, index, minindex); + index = minindex; + } +} + +void nghttp3_pq_pop(nghttp3_pq *pq) { + if (pq->length > 0) { + pq->q[0] = pq->q[pq->length - 1]; + pq->q[0]->index = 0; + --pq->length; + bubble_down(pq, 0); + } +} + +void nghttp3_pq_remove(nghttp3_pq *pq, nghttp3_pq_entry *item) { + assert(pq->q[item->index] == item); + + if (item->index == 0) { + nghttp3_pq_pop(pq); + return; + } + + if (item->index == pq->length - 1) { + --pq->length; + return; + } + + pq->q[item->index] = pq->q[pq->length - 1]; + pq->q[item->index]->index = item->index; + --pq->length; + + if (pq->less(item, pq->q[item->index])) { + bubble_down(pq, item->index); + } else { + bubble_up(pq, item->index); + } +} + +int nghttp3_pq_empty(const nghttp3_pq *pq) { return pq->length == 0; } + +size_t nghttp3_pq_size(const nghttp3_pq *pq) { return pq->length; } + +int nghttp3_pq_each(const nghttp3_pq *pq, nghttp3_pq_item_cb fun, void *arg) { + size_t i; + + if (pq->length == 0) { + return 0; + } + for (i = 0; i < pq->length; ++i) { + if ((*fun)(pq->q[i], arg)) { + return 1; + } + } + return 0; +} + +void nghttp3_pq_clear(nghttp3_pq *pq) { pq->length = 0; } |