Luiz Capitulino | fb08dde | 2009-08-28 15:27:07 -0300 | [diff] [blame] | 1 | /* |
| 2 | * QDict data type. |
| 3 | * |
| 4 | * Copyright (C) 2009 Red Hat Inc. |
| 5 | * |
| 6 | * Authors: |
| 7 | * Luiz Capitulino <lcapitulino@redhat.com> |
| 8 | * |
| 9 | * This work is licensed under the terms of the GNU GPL, version 2. See |
| 10 | * the COPYING file in the top-level directory. |
| 11 | */ |
| 12 | |
| 13 | #include "qint.h" |
| 14 | #include "qdict.h" |
| 15 | #include "qstring.h" |
| 16 | #include "qobject.h" |
Blue Swirl | 72cf2d4 | 2009-09-12 07:36:22 +0000 | [diff] [blame] | 17 | #include "qemu-queue.h" |
Luiz Capitulino | fb08dde | 2009-08-28 15:27:07 -0300 | [diff] [blame] | 18 | #include "qemu-common.h" |
| 19 | |
Blue Swirl | aa43d9c | 2009-09-04 17:43:37 +0000 | [diff] [blame] | 20 | static void qdict_destroy_obj(QObject *obj); |
| 21 | |
| 22 | static const QType qdict_type = { |
| 23 | .code = QTYPE_QDICT, |
| 24 | .destroy = qdict_destroy_obj, |
| 25 | }; |
Luiz Capitulino | fb08dde | 2009-08-28 15:27:07 -0300 | [diff] [blame] | 26 | |
| 27 | /** |
| 28 | * qdict_new(): Create a new QDict |
| 29 | * |
| 30 | * Return strong reference. |
| 31 | */ |
| 32 | QDict *qdict_new(void) |
| 33 | { |
| 34 | QDict *qdict; |
| 35 | |
| 36 | qdict = qemu_mallocz(sizeof(*qdict)); |
| 37 | QOBJECT_INIT(qdict, &qdict_type); |
| 38 | |
| 39 | return qdict; |
| 40 | } |
| 41 | |
| 42 | /** |
| 43 | * qobject_to_qdict(): Convert a QObject into a QDict |
| 44 | */ |
| 45 | QDict *qobject_to_qdict(const QObject *obj) |
| 46 | { |
| 47 | if (qobject_type(obj) != QTYPE_QDICT) |
| 48 | return NULL; |
| 49 | |
| 50 | return container_of(obj, QDict, base); |
| 51 | } |
| 52 | |
| 53 | /** |
| 54 | * tdb_hash(): based on the hash agorithm from gdbm, via tdb |
| 55 | * (from module-init-tools) |
| 56 | */ |
| 57 | static unsigned int tdb_hash(const char *name) |
| 58 | { |
| 59 | unsigned value; /* Used to compute the hash value. */ |
| 60 | unsigned i; /* Used to cycle through random values. */ |
| 61 | |
| 62 | /* Set the initial value from the key size. */ |
| 63 | for (value = 0x238F13AF * strlen(name), i=0; name[i]; i++) |
| 64 | value = (value + (((const unsigned char *)name)[i] << (i*5 % 24))); |
| 65 | |
| 66 | return (1103515243 * value + 12345); |
| 67 | } |
| 68 | |
| 69 | /** |
| 70 | * alloc_entry(): allocate a new QDictEntry |
| 71 | */ |
| 72 | static QDictEntry *alloc_entry(const char *key, QObject *value) |
| 73 | { |
| 74 | QDictEntry *entry; |
| 75 | |
| 76 | entry = qemu_mallocz(sizeof(*entry)); |
| 77 | entry->key = qemu_strdup(key); |
| 78 | entry->value = value; |
| 79 | |
| 80 | return entry; |
| 81 | } |
| 82 | |
| 83 | /** |
| 84 | * qdict_find(): List lookup function |
| 85 | */ |
| 86 | static QDictEntry *qdict_find(const QDict *qdict, |
| 87 | const char *key, unsigned int hash) |
| 88 | { |
| 89 | QDictEntry *entry; |
| 90 | |
Blue Swirl | 72cf2d4 | 2009-09-12 07:36:22 +0000 | [diff] [blame] | 91 | QLIST_FOREACH(entry, &qdict->table[hash], next) |
Luiz Capitulino | fb08dde | 2009-08-28 15:27:07 -0300 | [diff] [blame] | 92 | if (!strcmp(entry->key, key)) |
| 93 | return entry; |
| 94 | |
| 95 | return NULL; |
| 96 | } |
| 97 | |
| 98 | /** |
| 99 | * qdict_put_obj(): Put a new QObject into the dictionary |
| 100 | * |
| 101 | * Insert the pair 'key:value' into 'qdict', if 'key' already exists |
| 102 | * its 'value' will be replaced. |
| 103 | * |
| 104 | * This is done by freeing the reference to the stored QObject and |
| 105 | * storing the new one in the same entry. |
| 106 | * |
| 107 | * NOTE: ownership of 'value' is transferred to the QDict |
| 108 | */ |
| 109 | void qdict_put_obj(QDict *qdict, const char *key, QObject *value) |
| 110 | { |
| 111 | unsigned int hash; |
| 112 | QDictEntry *entry; |
| 113 | |
| 114 | hash = tdb_hash(key) % QDICT_HASH_SIZE; |
| 115 | entry = qdict_find(qdict, key, hash); |
| 116 | if (entry) { |
| 117 | /* replace key's value */ |
| 118 | qobject_decref(entry->value); |
| 119 | entry->value = value; |
| 120 | } else { |
| 121 | /* allocate a new entry */ |
| 122 | entry = alloc_entry(key, value); |
Blue Swirl | 72cf2d4 | 2009-09-12 07:36:22 +0000 | [diff] [blame] | 123 | QLIST_INSERT_HEAD(&qdict->table[hash], entry, next); |
Luiz Capitulino | fb08dde | 2009-08-28 15:27:07 -0300 | [diff] [blame] | 124 | } |
| 125 | |
| 126 | qdict->size++; |
| 127 | } |
| 128 | |
| 129 | /** |
| 130 | * qdict_get(): Lookup for a given 'key' |
| 131 | * |
| 132 | * Return a weak reference to the QObject associated with 'key' if |
| 133 | * 'key' is present in the dictionary, NULL otherwise. |
| 134 | */ |
| 135 | QObject *qdict_get(const QDict *qdict, const char *key) |
| 136 | { |
| 137 | QDictEntry *entry; |
| 138 | |
| 139 | entry = qdict_find(qdict, key, tdb_hash(key) % QDICT_HASH_SIZE); |
| 140 | return (entry == NULL ? NULL : entry->value); |
| 141 | } |
| 142 | |
| 143 | /** |
| 144 | * qdict_haskey(): Check if 'key' exists |
| 145 | * |
| 146 | * Return 1 if 'key' exists in the dict, 0 otherwise |
| 147 | */ |
| 148 | int qdict_haskey(const QDict *qdict, const char *key) |
| 149 | { |
| 150 | unsigned int hash = tdb_hash(key) % QDICT_HASH_SIZE; |
| 151 | return (qdict_find(qdict, key, hash) == NULL ? 0 : 1); |
| 152 | } |
| 153 | |
| 154 | /** |
| 155 | * qdict_size(): Return the size of the dictionary |
| 156 | */ |
| 157 | size_t qdict_size(const QDict *qdict) |
| 158 | { |
| 159 | return qdict->size; |
| 160 | } |
| 161 | |
| 162 | /** |
| 163 | * qdict_get_obj(): Get a QObject of a specific type |
| 164 | */ |
| 165 | static QObject *qdict_get_obj(const QDict *qdict, const char *key, |
| 166 | qtype_code type) |
| 167 | { |
| 168 | QObject *obj; |
| 169 | |
| 170 | obj = qdict_get(qdict, key); |
| 171 | assert(obj != NULL); |
| 172 | assert(qobject_type(obj) == type); |
| 173 | |
| 174 | return obj; |
| 175 | } |
| 176 | |
| 177 | /** |
| 178 | * qdict_get_int(): Get an integer mapped by 'key' |
| 179 | * |
| 180 | * This function assumes that 'key' exists and it stores a |
| 181 | * QInt object. |
| 182 | * |
| 183 | * Return integer mapped by 'key'. |
| 184 | */ |
| 185 | int64_t qdict_get_int(const QDict *qdict, const char *key) |
| 186 | { |
| 187 | QObject *obj = qdict_get_obj(qdict, key, QTYPE_QINT); |
| 188 | return qint_get_int(qobject_to_qint(obj)); |
| 189 | } |
| 190 | |
| 191 | /** |
| 192 | * qdict_get_str(): Get a pointer to the stored string mapped |
| 193 | * by 'key' |
| 194 | * |
| 195 | * This function assumes that 'key' exists and it stores a |
| 196 | * QString object. |
| 197 | * |
| 198 | * Return pointer to the string mapped by 'key'. |
| 199 | */ |
| 200 | const char *qdict_get_str(const QDict *qdict, const char *key) |
| 201 | { |
| 202 | QObject *obj = qdict_get_obj(qdict, key, QTYPE_QSTRING); |
| 203 | return qstring_get_str(qobject_to_qstring(obj)); |
| 204 | } |
| 205 | |
| 206 | /** |
| 207 | * qdict_get_try_int(): Try to get integer mapped by 'key' |
| 208 | * |
| 209 | * Return integer mapped by 'key', if it is not present in |
| 210 | * the dictionary or if the stored object is not of QInt type |
| 211 | * 'err_value' will be returned. |
| 212 | */ |
| 213 | int64_t qdict_get_try_int(const QDict *qdict, const char *key, |
| 214 | int64_t err_value) |
| 215 | { |
| 216 | QObject *obj; |
| 217 | |
| 218 | obj = qdict_get(qdict, key); |
| 219 | if (!obj || qobject_type(obj) != QTYPE_QINT) |
| 220 | return err_value; |
| 221 | |
| 222 | return qint_get_int(qobject_to_qint(obj)); |
| 223 | } |
| 224 | |
| 225 | /** |
| 226 | * qdict_get_try_str(): Try to get a pointer to the stored string |
| 227 | * mapped by 'key' |
| 228 | * |
| 229 | * Return a pointer to the string mapped by 'key', if it is not present |
| 230 | * in the dictionary or if the stored object is not of QString type |
| 231 | * NULL will be returned. |
| 232 | */ |
| 233 | const char *qdict_get_try_str(const QDict *qdict, const char *key) |
| 234 | { |
| 235 | QObject *obj; |
| 236 | |
| 237 | obj = qdict_get(qdict, key); |
| 238 | if (!obj || qobject_type(obj) != QTYPE_QSTRING) |
| 239 | return NULL; |
| 240 | |
| 241 | return qstring_get_str(qobject_to_qstring(obj)); |
| 242 | } |
| 243 | |
| 244 | /** |
| 245 | * qentry_destroy(): Free all the memory allocated by a QDictEntry |
| 246 | */ |
| 247 | static void qentry_destroy(QDictEntry *e) |
| 248 | { |
| 249 | assert(e != NULL); |
| 250 | assert(e->key != NULL); |
| 251 | assert(e->value != NULL); |
| 252 | |
| 253 | qobject_decref(e->value); |
| 254 | qemu_free(e->key); |
| 255 | qemu_free(e); |
| 256 | } |
| 257 | |
| 258 | /** |
| 259 | * qdict_del(): Delete a 'key:value' pair from the dictionary |
| 260 | * |
| 261 | * This will destroy all data allocated by this entry. |
| 262 | */ |
| 263 | void qdict_del(QDict *qdict, const char *key) |
| 264 | { |
| 265 | QDictEntry *entry; |
| 266 | |
| 267 | entry = qdict_find(qdict, key, tdb_hash(key) % QDICT_HASH_SIZE); |
| 268 | if (entry) { |
Blue Swirl | 72cf2d4 | 2009-09-12 07:36:22 +0000 | [diff] [blame] | 269 | QLIST_REMOVE(entry, next); |
Luiz Capitulino | fb08dde | 2009-08-28 15:27:07 -0300 | [diff] [blame] | 270 | qentry_destroy(entry); |
| 271 | qdict->size--; |
| 272 | } |
| 273 | } |
| 274 | |
| 275 | /** |
| 276 | * qdict_destroy_obj(): Free all the memory allocated by a QDict |
| 277 | */ |
| 278 | static void qdict_destroy_obj(QObject *obj) |
| 279 | { |
| 280 | int i; |
| 281 | QDict *qdict; |
| 282 | |
| 283 | assert(obj != NULL); |
| 284 | qdict = qobject_to_qdict(obj); |
| 285 | |
| 286 | for (i = 0; i < QDICT_HASH_SIZE; i++) { |
Blue Swirl | 72cf2d4 | 2009-09-12 07:36:22 +0000 | [diff] [blame] | 287 | QDictEntry *entry = QLIST_FIRST(&qdict->table[i]); |
Luiz Capitulino | fb08dde | 2009-08-28 15:27:07 -0300 | [diff] [blame] | 288 | while (entry) { |
Blue Swirl | 72cf2d4 | 2009-09-12 07:36:22 +0000 | [diff] [blame] | 289 | QDictEntry *tmp = QLIST_NEXT(entry, next); |
| 290 | QLIST_REMOVE(entry, next); |
Luiz Capitulino | fb08dde | 2009-08-28 15:27:07 -0300 | [diff] [blame] | 291 | qentry_destroy(entry); |
| 292 | entry = tmp; |
| 293 | } |
| 294 | } |
| 295 | |
| 296 | qemu_free(qdict); |
| 297 | } |