**/
#include "collectd.h"
+
#include "plugin.h"
#include "meta_data.h"
-#include <pthread.h>
-
/*
* Data types
*/
return (e);
} /* }}} meta_entry_t *md_entry_alloc */
-static meta_entry_t *md_entry_clone (const meta_entry_t *orig) /* {{{ */
+/* XXX: The lock on md must be held while calling this function! */
+static meta_entry_t *md_entry_clone_contents (const meta_entry_t *orig) /* {{{ */
{
meta_entry_t *copy;
- if (orig == NULL)
- return (NULL);
+ /* WARNINGS :
+ * - we do not check that orig != NULL here. You should have done it before.
+ * - we do not set copy->next. DO NOT FORGET TO SET copy->next IN YOUR FUNCTION
+ */
copy = md_entry_alloc (orig->key);
if (copy == NULL)
else
copy->value = orig->value;
+ return (copy);
+} /* }}} meta_entry_t *md_entry_clone_contents */
+
+static meta_entry_t *md_entry_clone (const meta_entry_t *orig) /* {{{ */
+{
+ meta_entry_t *copy;
+
+ if (orig == NULL)
+ return (NULL);
+
+ copy = md_entry_clone_contents(orig);
+
copy->next = md_entry_clone (orig->next);
return (copy);
} /* }}} meta_entry_t *md_entry_clone */
} /* }}} int md_entry_insert */
/* XXX: The lock on md must be held while calling this function! */
+static int md_entry_insert_clone (meta_data_t *md, meta_entry_t *orig) /* {{{ */
+{
+ meta_entry_t *e;
+ meta_entry_t *this;
+ meta_entry_t *prev;
+
+ /* WARNINGS :
+ * - we do not check that md and e != NULL here. You should have done it before.
+ * - we do not use the lock. You should have set it before.
+ */
+
+ e = md_entry_clone_contents(orig);
+
+ prev = NULL;
+ this = md->head;
+ while (this != NULL)
+ {
+ if (strcasecmp (e->key, this->key) == 0)
+ break;
+
+ prev = this;
+ this = this->next;
+ }
+
+ if (this == NULL)
+ {
+ /* This key does not exist yet. */
+ if (md->head == NULL)
+ md->head = e;
+ else
+ {
+ assert (prev != NULL);
+ prev->next = e;
+ }
+
+ e->next = NULL;
+ }
+ else /* (this != NULL) */
+ {
+ if (prev == NULL)
+ md->head = e;
+ else
+ prev->next = e;
+
+ e->next = this->next;
+ }
+
+ if (this != NULL)
+ {
+ this->next = NULL;
+ md_entry_free (this);
+ }
+
+ return (0);
+} /* }}} int md_entry_insert_clone */
+
+/* XXX: The lock on md must be held while calling this function! */
static meta_entry_t *md_entry_lookup (meta_data_t *md, /* {{{ */
const char *key)
{
} /* }}} meta_entry_t *md_entry_lookup */
/*
+ * Each value_list_t*, as it is going through the system, is handled by exactly
+ * one thread. Plugins which pass a value_list_t* to another thread, e.g. the
+ * rrdtool plugin, must create a copy first. The meta data within a
+ * value_list_t* is not thread safe and doesn't need to be.
+ *
+ * The meta data associated with cache entries are a different story. There, we
+ * need to ensure exclusive locking to prevent leaks and other funky business.
+ * This is ensured by the uc_meta_data_get_*() functions.
+ */
+
+/*
* Public functions
*/
meta_data_t *meta_data_create (void) /* {{{ */
return (copy);
} /* }}} meta_data_t *meta_data_clone */
+int meta_data_clone_merge (meta_data_t **dest, meta_data_t *orig) /* {{{ */
+{
+ if (orig == NULL)
+ return (0);
+
+ if (*dest == NULL) {
+ *dest = meta_data_clone(orig);
+ return(0);
+ }
+
+ pthread_mutex_lock (&orig->lock);
+ for (meta_entry_t *e=orig->head; e != NULL; e = e->next)
+ {
+ md_entry_insert_clone((*dest), e);
+ }
+ pthread_mutex_unlock (&orig->lock);
+
+ return (0);
+} /* }}} int meta_data_clone_merge */
+
void meta_data_destroy (meta_data_t *md) /* {{{ */
{
if (md == NULL)
int meta_data_exists (meta_data_t *md, const char *key) /* {{{ */
{
- meta_entry_t *e;
-
if ((md == NULL) || (key == NULL))
return (-EINVAL);
pthread_mutex_lock (&md->lock);
- for (e = md->head; e != NULL; e = e->next)
+ for (meta_entry_t *e = md->head; e != NULL; e = e->next)
{
if (strcasecmp (key, e->key) == 0)
{
int meta_data_type (meta_data_t *md, const char *key) /* {{{ */
{
- meta_entry_t *e;
-
if ((md == NULL) || (key == NULL))
return -EINVAL;
pthread_mutex_lock (&md->lock);
- for (e = md->head; e != NULL; e = e->next)
+ for (meta_entry_t *e = md->head; e != NULL; e = e->next)
{
if (strcasecmp (key, e->key) == 0)
{
int meta_data_toc (meta_data_t *md, char ***toc) /* {{{ */
{
int i = 0, count = 0;
- meta_entry_t *e;
if ((md == NULL) || (toc == NULL))
return -EINVAL;
pthread_mutex_lock (&md->lock);
- for (e = md->head; e != NULL; e = e->next)
+ for (meta_entry_t *e = md->head; e != NULL; e = e->next)
++count;
if (count == 0)
}
*toc = calloc(count, sizeof(**toc));
- for (e = md->head; e != NULL; e = e->next)
+ for (meta_entry_t *e = md->head; e != NULL; e = e->next)
(*toc)[i++] = strdup(e->key);
pthread_mutex_unlock (&md->lock);