Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 1 | /* |
| 2 | * |
David Garcia Quintas | 3598d44 | 2016-03-15 14:53:05 -0700 | [diff] [blame] | 3 | * Copyright 2015-2016, Google Inc. |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 4 | * All rights reserved. |
| 5 | * |
| 6 | * Redistribution and use in source and binary forms, with or without |
| 7 | * modification, are permitted provided that the following conditions are |
| 8 | * met: |
| 9 | * |
| 10 | * * Redistributions of source code must retain the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer. |
| 12 | * * Redistributions in binary form must reproduce the above |
| 13 | * copyright notice, this list of conditions and the following disclaimer |
| 14 | * in the documentation and/or other materials provided with the |
| 15 | * distribution. |
| 16 | * * Neither the name of Google Inc. nor the names of its |
| 17 | * contributors may be used to endorse or promote products derived from |
| 18 | * this software without specific prior written permission. |
| 19 | * |
| 20 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 21 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 22 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| 23 | * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| 24 | * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 25 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| 26 | * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 27 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 28 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 29 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| 30 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 31 | * |
| 32 | */ |
| 33 | |
Craig Tiller | 9a4dddd | 2016-03-25 17:08:13 -0700 | [diff] [blame] | 34 | #ifndef GRPC_CORE_LIB_TRANSPORT_CHTTP2_HPACK_TABLE_H |
| 35 | #define GRPC_CORE_LIB_TRANSPORT_CHTTP2_HPACK_TABLE_H |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 36 | |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 37 | #include <grpc/support/port_platform.h> |
| 38 | #include <grpc/support/slice.h> |
Craig Tiller | f40df23 | 2016-03-25 13:38:14 -0700 | [diff] [blame] | 39 | #include "src/core/transport/metadata.h" |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 40 | |
| 41 | /* HPACK header table */ |
| 42 | |
| 43 | /* last index in the static table */ |
| 44 | #define GRPC_CHTTP2_LAST_STATIC_ENTRY 61 |
| 45 | |
| 46 | /* Initial table size as per the spec */ |
| 47 | #define GRPC_CHTTP2_INITIAL_HPACK_TABLE_SIZE 4096 |
| 48 | /* Maximum table size that we'll use */ |
| 49 | #define GRPC_CHTTP2_MAX_HPACK_TABLE_SIZE GRPC_CHTTP2_INITIAL_HPACK_TABLE_SIZE |
| 50 | /* Per entry overhead bytes as per the spec */ |
| 51 | #define GRPC_CHTTP2_HPACK_ENTRY_OVERHEAD 32 |
Craig Tiller | 027a74c | 2015-11-10 08:37:46 +0000 | [diff] [blame] | 52 | #if 0 |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 53 | /* Maximum number of entries we could possibly fit in the table, given defined |
| 54 | overheads */ |
| 55 | #define GRPC_CHTTP2_MAX_TABLE_COUNT \ |
| 56 | ((GRPC_CHTTP2_MAX_HPACK_TABLE_SIZE + GRPC_CHTTP2_HPACK_ENTRY_OVERHEAD - 1) / \ |
| 57 | GRPC_CHTTP2_HPACK_ENTRY_OVERHEAD) |
Craig Tiller | 027a74c | 2015-11-10 08:37:46 +0000 | [diff] [blame] | 58 | #endif |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 59 | |
| 60 | /* hpack decoder table */ |
| 61 | typedef struct { |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 62 | /* the first used entry in ents */ |
Craig Tiller | 7536af0 | 2015-12-22 13:49:30 -0800 | [diff] [blame] | 63 | uint32_t first_ent; |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 64 | /* how many entries are in the table */ |
Craig Tiller | 7536af0 | 2015-12-22 13:49:30 -0800 | [diff] [blame] | 65 | uint32_t num_ents; |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 66 | /* the amount of memory used by the table, according to the hpack algorithm */ |
Craig Tiller | 7536af0 | 2015-12-22 13:49:30 -0800 | [diff] [blame] | 67 | uint32_t mem_used; |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 68 | /* the max memory allowed to be used by the table, according to the hpack |
| 69 | algorithm */ |
Craig Tiller | 7536af0 | 2015-12-22 13:49:30 -0800 | [diff] [blame] | 70 | uint32_t max_bytes; |
Craig Tiller | 027a74c | 2015-11-10 08:37:46 +0000 | [diff] [blame] | 71 | /* the currently agreed size of the table, according to the hpack algorithm */ |
Craig Tiller | 7536af0 | 2015-12-22 13:49:30 -0800 | [diff] [blame] | 72 | uint32_t current_table_bytes; |
Craig Tiller | 027a74c | 2015-11-10 08:37:46 +0000 | [diff] [blame] | 73 | /* Maximum number of entries we could possibly fit in the table, given defined |
| 74 | overheads */ |
Craig Tiller | 7536af0 | 2015-12-22 13:49:30 -0800 | [diff] [blame] | 75 | uint32_t max_entries; |
Craig Tiller | 027a74c | 2015-11-10 08:37:46 +0000 | [diff] [blame] | 76 | /* Number of entries allocated in ents */ |
Craig Tiller | 7536af0 | 2015-12-22 13:49:30 -0800 | [diff] [blame] | 77 | uint32_t cap_entries; |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 78 | /* a circular buffer of headers - this is stored in the opposite order to |
| 79 | what hpack specifies, in order to simplify table management a little... |
| 80 | meaning lookups need to SUBTRACT from the end position */ |
Craig Tiller | 027a74c | 2015-11-10 08:37:46 +0000 | [diff] [blame] | 81 | grpc_mdelem **ents; |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 82 | grpc_mdelem *static_ents[GRPC_CHTTP2_LAST_STATIC_ENTRY]; |
| 83 | } grpc_chttp2_hptbl; |
| 84 | |
| 85 | /* initialize a hpack table */ |
Craig Tiller | b2b4261 | 2015-11-20 12:02:17 -0800 | [diff] [blame] | 86 | void grpc_chttp2_hptbl_init(grpc_chttp2_hptbl *tbl); |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 87 | void grpc_chttp2_hptbl_destroy(grpc_chttp2_hptbl *tbl); |
Craig Tiller | 3c53bb2 | 2015-11-10 14:24:36 +0000 | [diff] [blame] | 88 | void grpc_chttp2_hptbl_set_max_bytes(grpc_chttp2_hptbl *tbl, |
Craig Tiller | 7536af0 | 2015-12-22 13:49:30 -0800 | [diff] [blame] | 89 | uint32_t max_bytes); |
Craig Tiller | 3c53bb2 | 2015-11-10 14:24:36 +0000 | [diff] [blame] | 90 | int grpc_chttp2_hptbl_set_current_table_size(grpc_chttp2_hptbl *tbl, |
Craig Tiller | 7536af0 | 2015-12-22 13:49:30 -0800 | [diff] [blame] | 91 | uint32_t bytes); |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 92 | |
| 93 | /* lookup a table entry based on its hpack index */ |
| 94 | grpc_mdelem *grpc_chttp2_hptbl_lookup(const grpc_chttp2_hptbl *tbl, |
Craig Tiller | 7536af0 | 2015-12-22 13:49:30 -0800 | [diff] [blame] | 95 | uint32_t index); |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 96 | /* add a table entry to the index */ |
Craig Tiller | 3c53bb2 | 2015-11-10 14:24:36 +0000 | [diff] [blame] | 97 | int grpc_chttp2_hptbl_add(grpc_chttp2_hptbl *tbl, |
| 98 | grpc_mdelem *md) GRPC_MUST_USE_RESULT; |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 99 | /* Find a key/value pair in the table... returns the index in the table of the |
| 100 | most similar entry, or 0 if the value was not found */ |
| 101 | typedef struct { |
Craig Tiller | 7536af0 | 2015-12-22 13:49:30 -0800 | [diff] [blame] | 102 | uint32_t index; |
Craig Tiller | 027a74c | 2015-11-10 08:37:46 +0000 | [diff] [blame] | 103 | int has_value; |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 104 | } grpc_chttp2_hptbl_find_result; |
| 105 | grpc_chttp2_hptbl_find_result grpc_chttp2_hptbl_find( |
| 106 | const grpc_chttp2_hptbl *tbl, grpc_mdelem *md); |
| 107 | |
Craig Tiller | 9a4dddd | 2016-03-25 17:08:13 -0700 | [diff] [blame] | 108 | #endif /* GRPC_CORE_LIB_TRANSPORT_CHTTP2_HPACK_TABLE_H */ |