1 /* 2 * ngtcp2 3 * 4 * Copyright (c) 2017 ngtcp2 contributors 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining 7 * a copy of this software and associated documentation files (the 8 * "Software"), to deal in the Software without restriction, including 9 * without limitation the rights to use, copy, modify, merge, publish, 10 * distribute, sublicense, and/or sell copies of the Software, and to 11 * permit persons to whom the Software is furnished to do so, subject to 12 * the following conditions: 13 * 14 * The above copyright notice and this permission notice shall be 15 * included in all copies or substantial portions of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 20 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 21 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 22 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 23 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 24 */ 25 #ifndef NGTCP2_IDTR_H 26 #define NGTCP2_IDTR_H 27 28 #ifdef HAVE_CONFIG_H 29 # include <config.h> 30 #endif /* HAVE_CONFIG_H */ 31 32 #include <ngtcp2/ngtcp2.h> 33 34 #include "ngtcp2_mem.h" 35 #include "ngtcp2_gaptr.h" 36 37 /* 38 * ngtcp2_idtr tracks the usage of stream ID. 39 */ 40 typedef struct ngtcp2_idtr { 41 /* gap maintains the range of ID which is not used yet. Initially, 42 its range is [0, UINT64_MAX). */ 43 ngtcp2_gaptr gap; 44 /* server is nonzero if this object records server initiated stream 45 ID. */ 46 int server; 47 } ngtcp2_idtr; 48 49 /* 50 * ngtcp2_idtr_init initializes |idtr|. 51 * 52 * If this object records server initiated ID (even number), set 53 * |server| to nonzero. 54 */ 55 void ngtcp2_idtr_init(ngtcp2_idtr *idtr, int server, const ngtcp2_mem *mem); 56 57 /* 58 * ngtcp2_idtr_free frees resources allocated for |idtr|. 59 */ 60 void ngtcp2_idtr_free(ngtcp2_idtr *idtr); 61 62 /* 63 * ngtcp2_idtr_open claims that |stream_id| is in used. 64 * 65 * It returns 0 if it succeeds, or one of the following negative error 66 * codes: 67 * 68 * NGTCP2_ERR_STREAM_IN_USE 69 * ID has already been used. 70 * NGTCP2_ERR_NOMEM 71 * Out of memory. 72 */ 73 int ngtcp2_idtr_open(ngtcp2_idtr *idtr, int64_t stream_id); 74 75 /* 76 * ngtcp2_idtr_open tells whether ID |stream_id| is in used or not. 77 * 78 * It returns nonzero if |stream_id| is used. 79 */ 80 int ngtcp2_idtr_is_open(ngtcp2_idtr *idtr, int64_t stream_id); 81 82 /* 83 * ngtcp2_idtr_first_gap returns the first id of first gap. If there 84 * is no gap, it returns UINT64_MAX. The returned id is an id space 85 * used in this object internally, and not stream ID. 86 */ 87 uint64_t ngtcp2_idtr_first_gap(ngtcp2_idtr *idtr); 88 89 #endif /* NGTCP2_IDTR_H */ 90