diff options
| -rw-r--r-- | Makefile | 2 | ||||
| -rw-r--r-- | qdict.c | 297 | ||||
| -rw-r--r-- | qdict.h | 42 | ||||
| -rw-r--r-- | qobject.h | 1 |
4 files changed, 341 insertions, 1 deletions
@@ -91,7 +91,7 @@ obj-y += buffered_file.o migration.o migration-tcp.o net.o qemu-sockets.o obj-y += qemu-char.o aio.o net-checksum.o savevm.o obj-y += msmouse.o ps2.o obj-y += qdev.o qdev-properties.o ssi.o -obj-y += qint.o qstring.o +obj-y += qint.o qstring.o qdict.o obj-$(CONFIG_BRLAPI) += baum.o obj-$(CONFIG_WIN32) += tap-win32.o @@ -0,0 +1,297 @@ +/* + * QDict data type. + * + * Copyright (C) 2009 Red Hat Inc. + * + * Authors: + * Luiz Capitulino <lcapitulino@redhat.com> + * + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + */ + +#include "qint.h" +#include "qdict.h" +#include "qstring.h" +#include "qobject.h" +#include "sys-queue.h" +#include "qemu-common.h" + +static const QType qdict_type; + +/** + * qdict_new(): Create a new QDict + * + * Return strong reference. + */ +QDict *qdict_new(void) +{ + QDict *qdict; + + qdict = qemu_mallocz(sizeof(*qdict)); + QOBJECT_INIT(qdict, &qdict_type); + + return qdict; +} + +/** + * qobject_to_qdict(): Convert a QObject into a QDict + */ +QDict *qobject_to_qdict(const QObject *obj) +{ + if (qobject_type(obj) != QTYPE_QDICT) + return NULL; + + return container_of(obj, QDict, base); +} + +/** + * tdb_hash(): based on the hash agorithm from gdbm, via tdb + * (from module-init-tools) + */ +static unsigned int tdb_hash(const char *name) +{ + unsigned value; /* Used to compute the hash value. */ + unsigned i; /* Used to cycle through random values. */ + + /* Set the initial value from the key size. */ + for (value = 0x238F13AF * strlen(name), i=0; name[i]; i++) + value = (value + (((const unsigned char *)name)[i] << (i*5 % 24))); + + return (1103515243 * value + 12345); +} + +/** + * alloc_entry(): allocate a new QDictEntry + */ +static QDictEntry *alloc_entry(const char *key, QObject *value) +{ + QDictEntry *entry; + + entry = qemu_mallocz(sizeof(*entry)); + entry->key = qemu_strdup(key); + entry->value = value; + + return entry; +} + +/** + * qdict_find(): List lookup function + */ +static QDictEntry *qdict_find(const QDict *qdict, + const char *key, unsigned int hash) +{ + QDictEntry *entry; + + LIST_FOREACH(entry, &qdict->table[hash], next) + if (!strcmp(entry->key, key)) + return entry; + + return NULL; +} + +/** + * qdict_put_obj(): Put a new QObject into the dictionary + * + * Insert the pair 'key:value' into 'qdict', if 'key' already exists + * its 'value' will be replaced. + * + * This is done by freeing the reference to the stored QObject and + * storing the new one in the same entry. + * + * NOTE: ownership of 'value' is transferred to the QDict + */ +void qdict_put_obj(QDict *qdict, const char *key, QObject *value) +{ + unsigned int hash; + QDictEntry *entry; + + hash = tdb_hash(key) % QDICT_HASH_SIZE; + entry = qdict_find(qdict, key, hash); + if (entry) { + /* replace key's value */ + qobject_decref(entry->value); + entry->value = value; + } else { + /* allocate a new entry */ + entry = alloc_entry(key, value); + LIST_INSERT_HEAD(&qdict->table[hash], entry, next); + } + + qdict->size++; +} + +/** + * qdict_get(): Lookup for a given 'key' + * + * Return a weak reference to the QObject associated with 'key' if + * 'key' is present in the dictionary, NULL otherwise. + */ +QObject *qdict_get(const QDict *qdict, const char *key) +{ + QDictEntry *entry; + + entry = qdict_find(qdict, key, tdb_hash(key) % QDICT_HASH_SIZE); + return (entry == NULL ? NULL : entry->value); +} + +/** + * qdict_haskey(): Check if 'key' exists + * + * Return 1 if 'key' exists in the dict, 0 otherwise + */ +int qdict_haskey(const QDict *qdict, const char *key) +{ + unsigned int hash = tdb_hash(key) % QDICT_HASH_SIZE; + return (qdict_find(qdict, key, hash) == NULL ? 0 : 1); +} + +/** + * qdict_size(): Return the size of the dictionary + */ +size_t qdict_size(const QDict *qdict) +{ + return qdict->size; +} + +/** + * qdict_get_obj(): Get a QObject of a specific type + */ +static QObject *qdict_get_obj(const QDict *qdict, const char *key, + qtype_code type) +{ + QObject *obj; + + obj = qdict_get(qdict, key); + assert(obj != NULL); + assert(qobject_type(obj) == type); + + return obj; +} + +/** + * qdict_get_int(): Get an integer mapped by 'key' + * + * This function assumes that 'key' exists and it stores a + * QInt object. + * + * Return integer mapped by 'key'. + */ +int64_t qdict_get_int(const QDict *qdict, const char *key) +{ + QObject *obj = qdict_get_obj(qdict, key, QTYPE_QINT); + return qint_get_int(qobject_to_qint(obj)); +} + +/** + * qdict_get_str(): Get a pointer to the stored string mapped + * by 'key' + * + * This function assumes that 'key' exists and it stores a + * QString object. + * + * Return pointer to the string mapped by 'key'. + */ +const char *qdict_get_str(const QDict *qdict, const char *key) +{ + QObject *obj = qdict_get_obj(qdict, key, QTYPE_QSTRING); + return qstring_get_str(qobject_to_qstring(obj)); +} + +/** + * qdict_get_try_int(): Try to get integer mapped by 'key' + * + * Return integer mapped by 'key', if it is not present in + * the dictionary or if the stored object is not of QInt type + * 'err_value' will be returned. + */ +int64_t qdict_get_try_int(const QDict *qdict, const char *key, + int64_t err_value) +{ + QObject *obj; + + obj = qdict_get(qdict, key); + if (!obj || qobject_type(obj) != QTYPE_QINT) + return err_value; + + return qint_get_int(qobject_to_qint(obj)); +} + +/** + * qdict_get_try_str(): Try to get a pointer to the stored string + * mapped by 'key' + * + * Return a pointer to the string mapped by 'key', if it is not present + * in the dictionary or if the stored object is not of QString type + * NULL will be returned. + */ +const char *qdict_get_try_str(const QDict *qdict, const char *key) +{ + QObject *obj; + + obj = qdict_get(qdict, key); + if (!obj || qobject_type(obj) != QTYPE_QSTRING) + return NULL; + + return qstring_get_str(qobject_to_qstring(obj)); +} + +/** + * qentry_destroy(): Free all the memory allocated by a QDictEntry + */ +static void qentry_destroy(QDictEntry *e) +{ + assert(e != NULL); + assert(e->key != NULL); + assert(e->value != NULL); + + qobject_decref(e->value); + qemu_free(e->key); + qemu_free(e); +} + +/** + * qdict_del(): Delete a 'key:value' pair from the dictionary + * + * This will destroy all data allocated by this entry. + */ +void qdict_del(QDict *qdict, const char *key) +{ + QDictEntry *entry; + + entry = qdict_find(qdict, key, tdb_hash(key) % QDICT_HASH_SIZE); + if (entry) { + LIST_REMOVE(entry, next); + qentry_destroy(entry); + qdict->size--; + } +} + +/** + * qdict_destroy_obj(): Free all the memory allocated by a QDict + */ +static void qdict_destroy_obj(QObject *obj) +{ + int i; + QDict *qdict; + + assert(obj != NULL); + qdict = qobject_to_qdict(obj); + + for (i = 0; i < QDICT_HASH_SIZE; i++) { + QDictEntry *entry = LIST_FIRST(&qdict->table[i]); + while (entry) { + QDictEntry *tmp = LIST_NEXT(entry, next); + LIST_REMOVE(entry, next); + qentry_destroy(entry); + entry = tmp; + } + } + + qemu_free(qdict); +} + +static const QType qdict_type = { + .code = QTYPE_QDICT, + .destroy = qdict_destroy_obj, +}; @@ -0,0 +1,42 @@ +#ifndef QDICT_H +#define QDICT_H + +#include "qobject.h" +#include "sys-queue.h" +#include <stdint.h> + +#define QDICT_HASH_SIZE 512 + +typedef struct QDictEntry { + char *key; + QObject *value; + LIST_ENTRY(QDictEntry) next; +} QDictEntry; + +typedef struct QDict { + QObject_HEAD; + size_t size; + LIST_HEAD(,QDictEntry) table[QDICT_HASH_SIZE]; +} QDict; + +/* Object API */ +QDict *qdict_new(void); +size_t qdict_size(const QDict *qdict); +void qdict_put_obj(QDict *qdict, const char *key, QObject *value); +void qdict_del(QDict *qdict, const char *key); +int qdict_haskey(const QDict *qdict, const char *key); +QObject *qdict_get(const QDict *qdict, const char *key); +QDict *qobject_to_qdict(const QObject *obj); + +/* Helper to qdict_put_obj(), accepts any object */ +#define qdict_put(qdict, key, obj) \ + qdict_put_obj(qdict, key, QOBJECT(obj)) + +/* High level helpers */ +int64_t qdict_get_int(const QDict *qdict, const char *key); +const char *qdict_get_str(const QDict *qdict, const char *key); +int64_t qdict_get_try_int(const QDict *qdict, const char *key, + int64_t err_value); +const char *qdict_get_try_str(const QDict *qdict, const char *key); + +#endif /* QDICT_H */ @@ -39,6 +39,7 @@ typedef enum { QTYPE_NONE, QTYPE_QINT, QTYPE_QSTRING, + QTYPE_QDICT, } qtype_code; struct QObject; |