| 1 | /* $Id: strcache.h 106061 2024-09-16 14:03:52Z vboxsync $ */
|
|---|
| 2 | /** @file
|
|---|
| 3 | * IPRT - String Cache, stub implementation.
|
|---|
| 4 | */
|
|---|
| 5 |
|
|---|
| 6 | /*
|
|---|
| 7 | * Copyright (C) 2009-2024 Oracle and/or its affiliates.
|
|---|
| 8 | *
|
|---|
| 9 | * This file is part of VirtualBox base platform packages, as
|
|---|
| 10 | * available from https://www.virtualbox.org.
|
|---|
| 11 | *
|
|---|
| 12 | * This program is free software; you can redistribute it and/or
|
|---|
| 13 | * modify it under the terms of the GNU General Public License
|
|---|
| 14 | * as published by the Free Software Foundation, in version 3 of the
|
|---|
| 15 | * License.
|
|---|
| 16 | *
|
|---|
| 17 | * This program is distributed in the hope that it will be useful, but
|
|---|
| 18 | * WITHOUT ANY WARRANTY; without even the implied warranty of
|
|---|
| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|---|
| 20 | * General Public License for more details.
|
|---|
| 21 | *
|
|---|
| 22 | * You should have received a copy of the GNU General Public License
|
|---|
| 23 | * along with this program; if not, see <https://www.gnu.org/licenses>.
|
|---|
| 24 | *
|
|---|
| 25 | * The contents of this file may alternatively be used under the terms
|
|---|
| 26 | * of the Common Development and Distribution License Version 1.0
|
|---|
| 27 | * (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
|
|---|
| 28 | * in the VirtualBox distribution, in which case the provisions of the
|
|---|
| 29 | * CDDL are applicable instead of those of the GPL.
|
|---|
| 30 | *
|
|---|
| 31 | * You may elect to license modified versions of this file under the
|
|---|
| 32 | * terms and conditions of either the GPL or the CDDL or both.
|
|---|
| 33 | *
|
|---|
| 34 | * SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
|
|---|
| 35 | */
|
|---|
| 36 |
|
|---|
| 37 | #ifndef IPRT_INCLUDED_strcache_h
|
|---|
| 38 | #define IPRT_INCLUDED_strcache_h
|
|---|
| 39 | #ifndef RT_WITHOUT_PRAGMA_ONCE
|
|---|
| 40 | # pragma once
|
|---|
| 41 | #endif
|
|---|
| 42 |
|
|---|
| 43 | #include <iprt/types.h>
|
|---|
| 44 |
|
|---|
| 45 | RT_C_DECLS_BEGIN
|
|---|
| 46 |
|
|---|
| 47 |
|
|---|
| 48 | /**
|
|---|
| 49 | * Create a new string cache.
|
|---|
| 50 | *
|
|---|
| 51 | * @returns IPRT status code
|
|---|
| 52 | *
|
|---|
| 53 | * @param phStrCache Where to return the string cache handle.
|
|---|
| 54 | * @param pszName The name of the cache (for debug purposes).
|
|---|
| 55 | */
|
|---|
| 56 | RTDECL(int) RTStrCacheCreate(PRTSTRCACHE phStrCache, const char *pszName);
|
|---|
| 57 |
|
|---|
| 58 |
|
|---|
| 59 | /**
|
|---|
| 60 | * Destroys a string cache.
|
|---|
| 61 | *
|
|---|
| 62 | * This will cause all strings in the cache to be released and thus become
|
|---|
| 63 | * invalid.
|
|---|
| 64 | *
|
|---|
| 65 | * @returns IPRT status.
|
|---|
| 66 | *
|
|---|
| 67 | * @param hStrCache Handle to the string cache. The nil and default
|
|---|
| 68 | * handles are ignored quietly (VINF_SUCCESS).
|
|---|
| 69 | */
|
|---|
| 70 | RTDECL(int) RTStrCacheDestroy(RTSTRCACHE hStrCache);
|
|---|
| 71 |
|
|---|
| 72 |
|
|---|
| 73 | /**
|
|---|
| 74 | * Enters a string into the cache.
|
|---|
| 75 | *
|
|---|
| 76 | * @returns Pointer to a read-only copy of the string.
|
|---|
| 77 | *
|
|---|
| 78 | * @param hStrCache Handle to the string cache.
|
|---|
| 79 | * @param pchString Pointer to a string. This does not need to be
|
|---|
| 80 | * zero terminated, but must not contain any zero
|
|---|
| 81 | * characters.
|
|---|
| 82 | * @param cchString The number of characters (bytes) to enter.
|
|---|
| 83 | *
|
|---|
| 84 | * @remarks It is implementation dependent whether the returned string pointer
|
|---|
| 85 | * differs when entering the same string twice.
|
|---|
| 86 | */
|
|---|
| 87 | RTDECL(const char *) RTStrCacheEnterN(RTSTRCACHE hStrCache, const char *pchString, size_t cchString);
|
|---|
| 88 |
|
|---|
| 89 | /**
|
|---|
| 90 | * Enters a string into the cache.
|
|---|
| 91 | *
|
|---|
| 92 | * @returns Pointer to a read-only copy of the string.
|
|---|
| 93 | *
|
|---|
| 94 | * @param hStrCache Handle to the string cache.
|
|---|
| 95 | * @param psz Pointer to a zero terminated string.
|
|---|
| 96 | *
|
|---|
| 97 | * @remarks See RTStrCacheEnterN.
|
|---|
| 98 | */
|
|---|
| 99 | RTDECL(const char *) RTStrCacheEnter(RTSTRCACHE hStrCache, const char *psz);
|
|---|
| 100 |
|
|---|
| 101 |
|
|---|
| 102 | /**
|
|---|
| 103 | * Enters a string into the cache in lower cased form.
|
|---|
| 104 | *
|
|---|
| 105 | * @returns Pointer to a read-only lower cased copy of the string.
|
|---|
| 106 | *
|
|---|
| 107 | * @param hStrCache Handle to the string cache.
|
|---|
| 108 | * @param pchString Pointer to a string. This does not need to be
|
|---|
| 109 | * zero terminated, but must not contain any zero
|
|---|
| 110 | * characters.
|
|---|
| 111 | * @param cchString The number of characters (bytes) to enter.
|
|---|
| 112 | *
|
|---|
| 113 | * @remarks It is implementation dependent whether the returned string pointer
|
|---|
| 114 | * differs when entering the same string twice.
|
|---|
| 115 | */
|
|---|
| 116 | RTDECL(const char *) RTStrCacheEnterLowerN(RTSTRCACHE hStrCache, const char *pchString, size_t cchString);
|
|---|
| 117 |
|
|---|
| 118 | /**
|
|---|
| 119 | * Enters a string into the cache in lower cased form.
|
|---|
| 120 | *
|
|---|
| 121 | * @returns Pointer to a read-only lower cased copy of the string.
|
|---|
| 122 | *
|
|---|
| 123 | * @param hStrCache Handle to the string cache.
|
|---|
| 124 | * @param psz Pointer to a zero terminated string.
|
|---|
| 125 | *
|
|---|
| 126 | * @remarks See RTStrCacheEnterN.
|
|---|
| 127 | */
|
|---|
| 128 | RTDECL(const char *) RTStrCacheEnterLower(RTSTRCACHE hStrCache, const char *psz);
|
|---|
| 129 |
|
|---|
| 130 |
|
|---|
| 131 | /**
|
|---|
| 132 | * Retains a reference to a string.
|
|---|
| 133 | *
|
|---|
| 134 | * @returns The new reference count. UINT32_MAX is returned if the string
|
|---|
| 135 | * pointer is invalid.
|
|---|
| 136 | */
|
|---|
| 137 | RTDECL(uint32_t) RTStrCacheRetain(const char *psz);
|
|---|
| 138 |
|
|---|
| 139 | /**
|
|---|
| 140 | * Releases a reference to a string.
|
|---|
| 141 | *
|
|---|
| 142 | * @returns The new reference count.
|
|---|
| 143 | * UINT32_MAX is returned if the string pointer is invalid.
|
|---|
| 144 | *
|
|---|
| 145 | * @param hStrCache Handle to the string cache. NIL is NOT allowed.
|
|---|
| 146 | * @param psz Pointer to a cached string.
|
|---|
| 147 | */
|
|---|
| 148 | RTDECL(uint32_t) RTStrCacheRelease(RTSTRCACHE hStrCache, const char *psz);
|
|---|
| 149 |
|
|---|
| 150 | /**
|
|---|
| 151 | * Gets the string length of a cache entry.
|
|---|
| 152 | *
|
|---|
| 153 | * @returns The string length. 0 if the string is invalid (asserted).
|
|---|
| 154 | *
|
|---|
| 155 | * @param psz Pointer to a cached string.
|
|---|
| 156 | */
|
|---|
| 157 | RTDECL(size_t) RTStrCacheLength(const char *psz);
|
|---|
| 158 |
|
|---|
| 159 |
|
|---|
| 160 | /**
|
|---|
| 161 | * Gets cache statistics.
|
|---|
| 162 | *
|
|---|
| 163 | * All parameters, except @a hStrCache, are optional and can be NULL.
|
|---|
| 164 | *
|
|---|
| 165 | * @returns Number of strings, UINT32_MAX on failure (or not supported).
|
|---|
| 166 | * @param hStrCache Handle to the string cache.
|
|---|
| 167 | * @param pcbStrings The number of string bytes (including
|
|---|
| 168 | * terminators) .
|
|---|
| 169 | * @param pcbChunks Amount of memory we've allocated for the
|
|---|
| 170 | * internal allocator.
|
|---|
| 171 | * @param pcbBigEntries Amount of memory we've allocated off the heap
|
|---|
| 172 | * for really long strings that doesn't fit in the
|
|---|
| 173 | * internal allocator.
|
|---|
| 174 | * @param pcHashCollisions Number of hash table insert collisions.
|
|---|
| 175 | * @param pcHashCollisions2 Number of hash table secondary insert
|
|---|
| 176 | * collisions.
|
|---|
| 177 | * @param pcHashInserts Number of hash table inserts.
|
|---|
| 178 | * @param pcRehashes The number of rehashes.
|
|---|
| 179 | *
|
|---|
| 180 | * @remarks This is not a stable interface as it needs to reflect the cache
|
|---|
| 181 | * implementation.
|
|---|
| 182 | */
|
|---|
| 183 | RTDECL(uint32_t) RTStrCacheGetStats(RTSTRCACHE hStrCache, size_t *pcbStrings, size_t *pcbChunks, size_t *pcbBigEntries,
|
|---|
| 184 | uint32_t *pcHashCollisions, uint32_t *pcHashCollisions2, uint32_t *pcHashInserts,
|
|---|
| 185 | uint32_t *pcRehashes);
|
|---|
| 186 |
|
|---|
| 187 | /**
|
|---|
| 188 | * Indicates whether this a real string cache or a cheap place holder.
|
|---|
| 189 | *
|
|---|
| 190 | * A real string cache will return the same address when a string is added
|
|---|
| 191 | * multiple times.
|
|---|
| 192 | *
|
|---|
| 193 | * @returns true / false.
|
|---|
| 194 | */
|
|---|
| 195 | RTDECL(bool) RTStrCacheIsRealImpl(void);
|
|---|
| 196 |
|
|---|
| 197 |
|
|---|
| 198 | RT_C_DECLS_END
|
|---|
| 199 |
|
|---|
| 200 | #endif /* !IPRT_INCLUDED_strcache_h */
|
|---|
| 201 |
|
|---|
