dburgess | 82c46ff | 2011-10-07 02:40:51 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2009, 2010 Free Software Foundation, Inc. |
| 3 | * Copyright 2010 Kestrel Signal Processing, Inc. |
| 4 | * |
| 5 | * This software is distributed under the terms of the GNU Affero Public License. |
| 6 | * See the COPYING file in the main directory for details. |
| 7 | * |
| 8 | * This use of this software may be subject to additional restrictions. |
| 9 | * See the LEGAL file in the main directory for details. |
| 10 | |
| 11 | This program is free software: you can redistribute it and/or modify |
| 12 | it under the terms of the GNU Affero General Public License as published by |
| 13 | the Free Software Foundation, either version 3 of the License, or |
| 14 | (at your option) any later version. |
| 15 | |
| 16 | This program is distributed in the hope that it will be useful, |
| 17 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 18 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 19 | GNU Affero General Public License for more details. |
| 20 | |
| 21 | You should have received a copy of the GNU Affero General Public License |
| 22 | along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 23 | |
| 24 | */ |
| 25 | |
| 26 | |
| 27 | #ifndef CONFIGURATION_H |
| 28 | #define CONFIGURATION_H |
| 29 | |
| 30 | |
| 31 | #include "sqlite3util.h" |
| 32 | |
| 33 | #include <assert.h> |
| 34 | #include <stdlib.h> |
| 35 | |
| 36 | #include <map> |
| 37 | #include <vector> |
| 38 | #include <string> |
| 39 | #include <iostream> |
| 40 | |
| 41 | #include <Threads.h> |
| 42 | #include <stdint.h> |
| 43 | |
| 44 | |
| 45 | /** A class for configuration file errors. */ |
| 46 | class ConfigurationTableError {}; |
| 47 | |
| 48 | /** An exception thrown when a given config key isn't found. */ |
| 49 | class ConfigurationTableKeyNotFound : public ConfigurationTableError { |
| 50 | |
| 51 | private: |
| 52 | |
| 53 | std::string mKey; |
| 54 | |
| 55 | public: |
| 56 | |
| 57 | ConfigurationTableKeyNotFound(const std::string& wKey) |
| 58 | :mKey(wKey) |
| 59 | { std::cerr << "cannot find configuration value " << mKey << std::endl; } |
| 60 | |
| 61 | const std::string& key() const { return mKey; } |
| 62 | |
| 63 | }; |
| 64 | |
| 65 | |
| 66 | class ConfigurationRecord { |
| 67 | |
| 68 | private: |
| 69 | |
| 70 | std::string mValue; |
| 71 | long mNumber; |
| 72 | bool mDefined; |
| 73 | |
| 74 | public: |
| 75 | |
| 76 | ConfigurationRecord(bool wDefined=true): |
| 77 | mDefined(wDefined) |
| 78 | { } |
| 79 | |
| 80 | ConfigurationRecord(const std::string& wValue): |
| 81 | mValue(wValue), |
| 82 | mNumber(strtol(wValue.c_str(),NULL,0)), |
| 83 | mDefined(true) |
| 84 | { } |
| 85 | |
| 86 | ConfigurationRecord(const char* wValue): |
| 87 | mValue(std::string(wValue)), |
| 88 | mNumber(strtol(wValue,NULL,0)), |
| 89 | mDefined(true) |
| 90 | { } |
| 91 | |
| 92 | |
| 93 | const std::string& value() const { return mValue; } |
| 94 | long number() const { return mNumber; } |
| 95 | bool defined() const { return mDefined; } |
| 96 | |
| 97 | }; |
| 98 | |
| 99 | |
| 100 | /** A string class that uses a hash function for comparison. */ |
| 101 | class HashString : public std::string { |
| 102 | |
| 103 | |
| 104 | protected: |
| 105 | |
| 106 | uint64_t mHash; |
| 107 | |
| 108 | void computeHash(); |
| 109 | |
| 110 | |
| 111 | public: |
| 112 | |
| 113 | HashString(const char* src) |
| 114 | :std::string(src) |
| 115 | { |
| 116 | computeHash(); |
| 117 | } |
| 118 | |
| 119 | HashString(const std::string& src) |
| 120 | :std::string(src) |
| 121 | { |
| 122 | computeHash(); |
| 123 | } |
| 124 | |
| 125 | HashString() |
| 126 | { |
| 127 | mHash=0; |
| 128 | } |
| 129 | |
| 130 | HashString& operator=(std::string& src) |
| 131 | { |
| 132 | std::string::operator=(src); |
| 133 | computeHash(); |
| 134 | return *this; |
| 135 | } |
| 136 | |
| 137 | HashString& operator=(const char* src) |
| 138 | { |
| 139 | std::string::operator=(src); |
| 140 | computeHash(); |
| 141 | return *this; |
| 142 | } |
| 143 | |
| 144 | bool operator==(const HashString& other) |
| 145 | { |
| 146 | return mHash==other.mHash; |
| 147 | } |
| 148 | |
| 149 | bool operator<(const HashString& other) |
| 150 | { |
| 151 | return mHash<other.mHash; |
| 152 | } |
| 153 | |
| 154 | bool operator>(const HashString& other) |
| 155 | { |
| 156 | return mHash<other.mHash; |
| 157 | } |
| 158 | |
| 159 | uint64_t hash() const { return mHash; } |
| 160 | |
| 161 | }; |
| 162 | |
| 163 | |
| 164 | typedef std::map<HashString, ConfigurationRecord> ConfigurationMap; |
| 165 | |
| 166 | |
| 167 | /** |
| 168 | A class for maintaining a configuration key-value table, |
| 169 | based on sqlite3 and a local map-based cache. |
| 170 | Thread-safe, too. |
| 171 | */ |
| 172 | class ConfigurationTable { |
| 173 | |
| 174 | private: |
| 175 | |
| 176 | sqlite3* mDB; ///< database connection |
| 177 | ConfigurationMap mCache; ///< cache of recently access configuration values |
| 178 | mutable Mutex mLock; ///< control for multithreaded access to the cache |
| 179 | |
| 180 | public: |
| 181 | |
| 182 | |
| 183 | ConfigurationTable(const char* filename = ":memory:"); |
| 184 | |
| 185 | /** Return true if the key is used in the table. */ |
| 186 | bool defines(const std::string& key); |
| 187 | |
| 188 | /** Return true if this key is identified as static. */ |
| 189 | bool isStatic(const std::string& key) const; |
| 190 | |
| 191 | /** Return true if this key is identified as required (!optional). */ |
| 192 | bool isRequired(const std::string& key) const; |
| 193 | |
| 194 | /** |
| 195 | Get a string parameter from the table. |
| 196 | Throw ConfigurationTableKeyNotFound if not found. |
| 197 | */ |
| 198 | std::string getStr(const std::string& key); |
| 199 | |
| 200 | |
| 201 | /** |
| 202 | Get a string parameter from the table. |
| 203 | Define the parameter to the default value if not found. |
| 204 | */ |
| 205 | std::string getStr(const std::string& key, const char* defaultValue); |
| 206 | |
| 207 | |
| 208 | /** |
| 209 | Get a numeric parameter from the table. |
| 210 | Throw ConfigurationTableKeyNotFound if not found. |
| 211 | */ |
| 212 | long getNum(const std::string& key); |
| 213 | |
| 214 | /** |
| 215 | Get a numeric parameter from the table. |
| 216 | Define the parameter to the default value if not found. |
| 217 | */ |
| 218 | long getNum(const std::string& key, long defaultValue); |
| 219 | |
| 220 | /** |
| 221 | Get a numeric vector from the table. |
| 222 | */ |
| 223 | std::vector<unsigned> getVector(const std::string& key); |
| 224 | |
| 225 | /** Get length of a vector */ |
| 226 | unsigned getVectorLength(const std::string &key) |
| 227 | { return getVector(key).size(); } |
| 228 | |
| 229 | /** Set or change a value in the table. */ |
| 230 | bool set(const std::string& key, const std::string& value); |
| 231 | |
| 232 | /** Set or change a value in the table. */ |
| 233 | bool set(const std::string& key, long value); |
| 234 | |
| 235 | /** Create an entry in the table, no value though. */ |
| 236 | bool set(const std::string& key); |
| 237 | |
| 238 | /** |
| 239 | Remove a key from the table. |
| 240 | Will not remove static or required values. |
| 241 | @param key The key of the item to be deleted. |
| 242 | @return true if anything was actually removed. |
| 243 | */ |
| 244 | bool unset(const std::string& key); |
| 245 | |
| 246 | /** Search the table, dumping to a stream. */ |
| 247 | void find(const std::string& pattern, std::ostream&) const; |
| 248 | |
| 249 | /** Define the callback to purge the cache whenever the database changes. */ |
| 250 | void setUpdateHook(void(*)(void *,int ,char const *,char const *,sqlite3_int64)); |
| 251 | |
| 252 | /** purege cache if it exceeds a certain age */ |
| 253 | void checkCacheAge(); |
| 254 | |
| 255 | /** Delete all records from the cache. */ |
| 256 | void purge(); |
| 257 | |
| 258 | |
| 259 | private: |
| 260 | |
| 261 | /** |
| 262 | Attempt to lookup a record, cache if needed. |
| 263 | Throw ConfigurationTableKeyNotFound if not found. |
| 264 | Caller should hold mLock because the returned reference points into the cache. |
| 265 | */ |
| 266 | const ConfigurationRecord& lookup(const std::string& key); |
| 267 | |
| 268 | }; |
| 269 | |
| 270 | |
| 271 | |
| 272 | #endif |
| 273 | |
| 274 | |
| 275 | // vim: ts=4 sw=4 |