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Diffstat (limited to '')
| -rw-r--r-- | lib/ngtcp2_vec.c | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/lib/ngtcp2_vec.c b/lib/ngtcp2_vec.c new file mode 100644 index 0000000..257332e --- /dev/null +++ b/lib/ngtcp2_vec.c @@ -0,0 +1,243 @@ +/* + * ngtcp2 + * + * Copyright (c) 2018 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_vec.h" + +#include <string.h> +#include <assert.h> + +#include "ngtcp2_str.h" + +ngtcp2_vec *ngtcp2_vec_init(ngtcp2_vec *vec, const uint8_t *base, size_t len) { + vec->base = (uint8_t *)base; + vec->len = len; + return vec; +} + +int ngtcp2_vec_new(ngtcp2_vec **pvec, const uint8_t *data, size_t datalen, + const ngtcp2_mem *mem) { + size_t len; + uint8_t *p; + + len = sizeof(ngtcp2_vec) + datalen; + + *pvec = ngtcp2_mem_malloc(mem, len); + if (*pvec == NULL) { + return NGTCP2_ERR_NOMEM; + } + + p = (uint8_t *)(*pvec) + sizeof(ngtcp2_vec); + (*pvec)->base = p; + (*pvec)->len = datalen; + if (datalen) { + /* p = */ ngtcp2_cpymem(p, data, datalen); + } + + return 0; +} + +void ngtcp2_vec_del(ngtcp2_vec *vec, const ngtcp2_mem *mem) { + ngtcp2_mem_free(mem, vec); +} + +uint64_t ngtcp2_vec_len(const ngtcp2_vec *vec, size_t n) { + size_t i; + size_t res = 0; + + for (i = 0; i < n; ++i) { + res += vec[i].len; + } + + return res; +} + +int64_t ngtcp2_vec_len_varint(const ngtcp2_vec *vec, size_t n) { + uint64_t res = 0; + size_t len; + size_t i; + + for (i = 0; i < n; ++i) { + len = vec[i].len; + if (len > NGTCP2_MAX_VARINT - res) { + return -1; + } + + res += len; + } + + return (int64_t)res; +} + +ngtcp2_ssize ngtcp2_vec_split(ngtcp2_vec *src, size_t *psrccnt, ngtcp2_vec *dst, + size_t *pdstcnt, size_t left, size_t maxcnt) { + size_t i; + size_t srccnt = *psrccnt; + size_t nmove; + size_t extra = 0; + + for (i = 0; i < srccnt; ++i) { + if (left >= src[i].len) { + left -= src[i].len; + continue; + } + + if (*pdstcnt && src[srccnt - 1].base + src[srccnt - 1].len == dst[0].base) { + if (*pdstcnt + srccnt - i - 1 > maxcnt) { + return -1; + } + + dst[0].len += src[srccnt - 1].len; + dst[0].base = src[srccnt - 1].base; + extra = src[srccnt - 1].len; + --srccnt; + } else if (*pdstcnt + srccnt - i > maxcnt) { + return -1; + } + + if (left == 0) { + *psrccnt = i; + } else { + *psrccnt = i + 1; + } + + nmove = srccnt - i; + if (nmove) { + memmove(dst + nmove, dst, sizeof(ngtcp2_vec) * (*pdstcnt)); + *pdstcnt += nmove; + memcpy(dst, src + i, sizeof(ngtcp2_vec) * nmove); + } + + dst[0].len -= left; + dst[0].base += left; + src[i].len = left; + + if (nmove == 0) { + extra -= left; + } + + return (ngtcp2_ssize)(ngtcp2_vec_len(dst, nmove) + extra); + } + + return 0; +} + +size_t ngtcp2_vec_merge(ngtcp2_vec *dst, size_t *pdstcnt, ngtcp2_vec *src, + size_t *psrccnt, size_t left, size_t maxcnt) { + size_t orig_left = left; + size_t i; + ngtcp2_vec *a, *b; + + assert(maxcnt); + + if (*pdstcnt == 0) { + if (*psrccnt == 0) { + return 0; + } + + a = &dst[0]; + b = &src[0]; + + if (left >= b->len) { + *a = *b; + ++*pdstcnt; + left -= b->len; + i = 1; + } else { + a->len = left; + a->base = b->base; + + b->len -= left; + b->base += left; + + return left; + } + } else { + i = 0; + } + + for (; left && i < *psrccnt; ++i) { + a = &dst[*pdstcnt - 1]; + b = &src[i]; + + if (left >= b->len) { + if (a->base + a->len == b->base) { + a->len += b->len; + } else if (*pdstcnt == maxcnt) { + break; + } else { + dst[(*pdstcnt)++] = *b; + } + left -= b->len; + continue; + } + + if (a->base + a->len == b->base) { + a->len += left; + } else if (*pdstcnt == maxcnt) { + break; + } else { + dst[*pdstcnt].len = left; + dst[*pdstcnt].base = b->base; + ++*pdstcnt; + } + + b->len -= left; + b->base += left; + left = 0; + + break; + } + + memmove(src, src + i, sizeof(ngtcp2_vec) * (*psrccnt - i)); + *psrccnt -= i; + + return orig_left - left; +} + +size_t ngtcp2_vec_copy_at_most(ngtcp2_vec *dst, size_t dstcnt, + const ngtcp2_vec *src, size_t srccnt, + size_t left) { + size_t i, j; + + for (i = 0, j = 0; left > 0 && i < srccnt && j < dstcnt;) { + if (src[i].len == 0) { + ++i; + continue; + } + dst[j] = src[i]; + if (dst[j].len > left) { + dst[j].len = left; + return j + 1; + } + left -= dst[j].len; + ++i; + ++j; + } + + return j; +} + +void ngtcp2_vec_copy(ngtcp2_vec *dst, const ngtcp2_vec *src, size_t cnt) { + memcpy(dst, src, sizeof(ngtcp2_vec) * cnt); +} |