-/**
- * @file connection.c
- * @brief Handle pools of connections (threads, sockets, etc.)
- *
- * Version: $Id$
- *
+/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
- *
- * Copyright 2012 The FreeRADIUS server project
- * Copyright 2012 Alan DeKok <aland@deployingradius.com>
*/
+/**
+ * @file connection.c
+ * @brief Handle pools of connections (threads, sockets, etc.)
+ * @note This API must be used by all modules in the public distribution that
+ * maintain pools of connections.
+ *
+ * @copyright 2012 The FreeRADIUS server project
+ * @copyright 2012 Alan DeKok <aland@deployingradius.com>
+ */
#include <freeradius-devel/ident.h>
RCSID("$Id$")
#include <freeradius-devel/rad_assert.h>
-typedef struct fr_connection_t fr_connection_t;
-
-static int fr_connection_pool_check(fr_connection_pool_t *fc);
+typedef struct fr_connection fr_connection_t;
-struct fr_connection_t {
- fr_connection_t *prev, *next;
+static int fr_connection_pool_check(fr_connection_pool_t *pool);
- time_t start;
- time_t last_used;
-
- int num_uses;
- int used;
- int number; /* unique ID */
- void *connection;
+/** An individual connection within the connection pool
+ *
+ * Defines connection counters, timestamps, and holds a pointer to the
+ * connection handle itself.
+ *
+ * @see fr_connection_pool_t
+ */
+struct fr_connection {
+ fr_connection_t *prev; //!< Previous connection in list.
+ fr_connection_t *next; //!< Next connection in list.
+
+ time_t start; //!< Time connection was created.
+ time_t last_used; //!< Last time the connection was
+ //!< reserved.
+
+ int num_uses; //!< Number of times the connection
+ //!< has been reserved.
+ int in_use; //!< Whether the connection is currently
+ //!< reserved.
+ int number; //!< Unique ID assigned when the
+ //!< connection is created, these will
+ //!< monotonically increase over the
+ //!< lifetime of the connection pool.
+ void *connection; //!< Pointer to whatever the module
+ //!< uses for a connection handle.
};
-struct fr_connection_pool_t {
- int start;
- int min;
- int max;
- int spare;
- int cleanup_delay;
-
- unsigned int count; /* num connections spawned */
- int num; /* num connections in pool */
- int active; /* num connections active */
-
- time_t last_checked;
- time_t last_spawned;
- time_t last_failed;
- time_t last_complained;
- time_t last_throttled;
- time_t last_at_max;
-
- int max_uses;
- int lifetime;
- int idle_timeout;
- int spawning;
- int trigger; /* do triggering */
-
- fr_connection_t *head, *tail;
+/** A connection pool
+ *
+ * Defines the configuration of the connection pool, all the counters and
+ * timestamps related to the connection pool, the mutex that stops multiple
+ * threads leaving the pool in an inconsistent state, and the callbacks
+ * required to open, close and check the status of connections within the pool.
+ *
+ * @see fr_connection
+ */
+struct fr_connection_pool_t {
+ int start; //!< Number of initial connections
+ int min; //!< Minimum number of concurrent
+ //!< connections to keep open.
+ int max; //!< Maximum number of concurrent
+ //!< connections to allow.
+ int spare; //!< Number of spare connections to try
+ //!< and maintain.
+ int cleanup_delay; //!< How long a connection can go unused
+ //!< for before it's closed
+ //!< (0 is infinite)
+ int max_uses; //!< Maximum number of times a
+ //!< connection can be used before being
+ //!< closed.
+ int lifetime; //!< How long a connection can be open
+ //!< before being closed (irrespective
+ //!< of whether it's idle or not).
+ int idle_timeout; //!< How long a connection can be idle
+ //!< before being closed.
+
+ int trigger; //!< If TRUE execute connection triggers
+ //!< associated with the connection
+ //!< pool.
+
+ time_t last_checked; //!< Last time we pruned the connection
+ //!< pool.
+ time_t last_spawned; //!< Last time we spawned a connection.
+ time_t last_failed; //!< Last time we tried to spawn a
+ //!< a connection but failed.
+ time_t last_complained;//!< Last time we complained about
+ //!< configuration parameters.
+ time_t last_throttled; //!< Last time we refused to spawn a
+ //!< connection because the last
+ //!< connection failed.
+ time_t last_at_max; //!< Last time we hit the maximum number
+ //!< of allowed connections
+
+ unsigned int count; //!< Number of connections spawned over
+ //!< the lifetime of the pool.
+ int num; //!< Number of connections in the pool.
+ int active; //!< Number of currently reserved
+ //!< connections.
+
+ fr_connection_t *head; //!< Start of the connection list.
+ fr_connection_t *tail; //!< End of the connection list.
+
+ int spawning; //!< Whether we are currently attempting
+ //!< to spawn a new connection.
#ifdef HAVE_PTHREAD_H
- pthread_mutex_t mutex;
+ pthread_mutex_t mutex; //!< Mutex used to keep consistent state
+ //!< when making modifications in
+ //!< threaded mode.
#endif
- CONF_SECTION *cs;
- void *ctx;
+ CONF_SECTION *cs; //!< Configuration section holding
+ //!< the section of parsed config file
+ //!< that relates to this pool.
+ void *ctx; //!< Pointer to context data that will
+ //!< be passed to callbacks.
- char *log_prefix;
-
- fr_connection_create_t create;
- fr_connection_alive_t alive;
- fr_connection_delete_t delete;
+ char *log_prefix; //!< Log prefix to prepend to all log
+ //!< messages created by the connection
+ //!< pool code.
+
+ fr_connection_create_t create; //!< Function used to create new
+ //!< connections.
+ fr_connection_alive_t alive; //!< Function used to check status
+ //!< of connections.
+ fr_connection_delete_t delete; //!< Function used to close existing
+ //!< connections.
};
#define LOG_PREFIX "rlm_%s (%s)"
{ NULL, -1, 0, NULL, NULL }
};
-
-static void fr_connection_unlink(fr_connection_pool_t *fc,
+/** Removes a connection from the connection list
+ *
+ * @note Must be called with the mutex held.
+ *
+ * @param [in,out] pool to modify.
+ * @param [in] this Connection to delete.
+ */
+static void fr_connection_unlink(fr_connection_pool_t *pool,
fr_connection_t *this)
{
if (this->prev) {
- rad_assert(fc->head != this);
+ rad_assert(pool->head != this);
this->prev->next = this->next;
} else {
- rad_assert(fc->head == this);
- fc->head = this->next;
+ rad_assert(pool->head == this);
+ pool->head = this->next;
}
if (this->next) {
- rad_assert(fc->tail != this);
+ rad_assert(pool->tail != this);
this->next->prev = this->prev;
} else {
- rad_assert(fc->tail == this);
- fc->tail = this->prev;
+ rad_assert(pool->tail == this);
+ pool->tail = this->prev;
}
this->prev = this->next = NULL;
}
-
-static void fr_connection_link(fr_connection_pool_t *fc,
+/** Adds a connection to the connection list
+ *
+ * @note Must be called with the mutex held.
+ *
+ * @param [in,out] pool to modify.
+ * @param [in] this Connection to add.
+ */
+static void fr_connection_link(fr_connection_pool_t *pool,
fr_connection_t *this)
{
- rad_assert(fc != NULL);
+ rad_assert(pool != NULL);
rad_assert(this != NULL);
- rad_assert(fc->head != this);
- rad_assert(fc->tail != this);
+ rad_assert(pool->head != this);
+ rad_assert(pool->tail != this);
- if (fc->head) fc->head->prev = this;
- this->next = fc->head;
+ if (pool->head) pool->head->prev = this;
+ this->next = pool->head;
this->prev = NULL;
- fc->head = this;
- if (!fc->tail) {
+ pool->head = this;
+ if (!pool->tail) {
rad_assert(this->next == NULL);
- fc->tail = this;
+ pool->tail = this;
} else {
rad_assert(this->next != NULL);
}
}
-/*
- * Called with the mutex free.
+/** Spawns a new connection
+ *
+ * Spawns a new connection using the create callback, and returns it for
+ * adding to the connection list.
+ *
+ * @note Will call the 'open' trigger.
+ * @note Must be called with the mutex free.
+ *
+ * @param [in] pool
+ * @param [in] now Current time.
+ * @return the new connection struct or NULL on error.
*/
-static fr_connection_t *fr_connection_spawn(fr_connection_pool_t *fc,
+static fr_connection_t *fr_connection_spawn(fr_connection_pool_t *pool,
time_t now)
{
fr_connection_t *this;
void *conn;
- rad_assert(fc != NULL);
+ rad_assert(pool != NULL);
/*
* Prevent all threads from blocking if the resource
* were managing connections for appears to be unavailable.
*/
- if ((fc->num == 0) && fc->spawning) {
+ if ((pool->num == 0) && pool->spawning) {
return NULL;
}
- pthread_mutex_lock(&fc->mutex);
- rad_assert(fc->num <= fc->max);
+ pthread_mutex_lock(&pool->mutex);
+ rad_assert(pool->num <= pool->max);
- if ((fc->last_failed == now) || fc->spawning) {
+ if ((pool->last_failed == now) || pool->spawning) {
int complain = FALSE;
- if (fc->last_throttled != now) {
+ if (pool->last_throttled != now) {
complain = TRUE;
- fc->last_throttled = now;
+ pool->last_throttled = now;
}
- pthread_mutex_unlock(&fc->mutex);
+ pthread_mutex_unlock(&pool->mutex);
if (complain) {
- if (fc->spawning) {
+ if (pool->spawning) {
radlog(L_ERR, "%s: Cannot open new connection, "
"connection spawning already in "
- "progress", fc->log_prefix);
+ "progress", pool->log_prefix);
} else {
radlog(L_ERR, "%s: Last connection failed, "
"throttling connection spawn",
- fc->log_prefix);
+ pool->log_prefix);
}
}
return NULL;
}
- fc->spawning = TRUE;
+ pool->spawning = TRUE;
/*
* Unlock the mutex while we try to open a new
* that case, we want the other connections to continue
* to be used.
*/
- pthread_mutex_unlock(&fc->mutex);
+ pthread_mutex_unlock(&pool->mutex);
radlog(L_INFO, "%s: Opening additional connection (%i)",
- fc->log_prefix, fc->count);
+ pool->log_prefix, pool->count);
this = rad_malloc(sizeof(*this));
memset(this, 0, sizeof(*this));
* about other threads opening new connections, as we
* already have no free connections.
*/
- conn = fc->create(fc->ctx);
+ conn = pool->create(pool->ctx);
if (!conn) {
radlog(L_ERR, "%s: Opening connection failed (%i)",
- fc->log_prefix, fc->count);
+ pool->log_prefix, pool->count);
- fc->last_failed = now;
+ pool->last_failed = now;
free(this);
- fc->spawning = FALSE; /* atomic, so no lock is needed */
+ pool->spawning = FALSE; /* atomic, so no lock is needed */
return NULL;
}
radlog(L_INFO, "%s: Opening connection successful (%i)",
- fc->log_prefix, fc->count);
+ pool->log_prefix, pool->count);
this->start = now;
this->connection = conn;
* And lock the mutex again while we link the new
* connection back into the pool.
*/
- pthread_mutex_lock(&fc->mutex);
+ pthread_mutex_lock(&pool->mutex);
- this->number = fc->count++;
+ this->number = pool->count++;
this->last_used = now;
- fr_connection_link(fc, this);
- fc->num++;
- fc->spawning = FALSE;
- fc->last_spawned = time(NULL);
+ fr_connection_link(pool, this);
+ pool->num++;
+ pool->spawning = FALSE;
+ pool->last_spawned = time(NULL);
- pthread_mutex_unlock(&fc->mutex);
+ pthread_mutex_unlock(&pool->mutex);
- if (fc->trigger) exec_trigger(NULL, fc->cs, "open", TRUE);
+ if (pool->trigger) exec_trigger(NULL, pool->cs, "open", TRUE);
return this;
}
-
-int fr_connection_add(fr_connection_pool_t *fc, void *conn)
+/** Add a new connection to the pool
+ *
+ * If conn is not NULL will attempt to add that connection handle to the pool.
+ * If conn is NULL will attempt to spawn a new connection using the create
+ * callback.
+ *
+ * @note Will call the 'open' trigger.
+ *
+ * @param [in,out] pool to add connection to.
+ * @param [in] conn to add.
+ * @return 0 if the connection wasn't added else 1.
+ */
+int fr_connection_add(fr_connection_pool_t *pool, void *conn)
{
fr_connection_t *this;
- if (!fc) return 0;
+ if (!pool) return 0;
- pthread_mutex_lock(&fc->mutex);
+ pthread_mutex_lock(&pool->mutex);
if (!conn) {
- conn = fc->create(fc->ctx);
+ conn = pool->create(pool->ctx);
if (!conn) {
- pthread_mutex_unlock(&fc->mutex);
+ pthread_mutex_unlock(&pool->mutex);
return 0;
}
+
+ radlog(L_INFO, "%s: Opening connection successful (%i)",
+ pool->log_prefix, pool->count);
}
/*
* Too many connections: can't add it.
*/
- if (fc->num >= fc->max) {
- pthread_mutex_unlock(&fc->mutex);
+ if (pool->num >= pool->max) {
+ pthread_mutex_unlock(&pool->mutex);
return 0;
}
this->start = time(NULL);
this->connection = conn;
- this->number = fc->count++;
+ this->number = pool->count++;
this->last_used = time(NULL);
- fr_connection_link(fc, this);
- fc->num++;
+ fr_connection_link(pool, this);
+ pool->num++;
- pthread_mutex_unlock(&fc->mutex);
+ pthread_mutex_unlock(&pool->mutex);
- if (fc->trigger) exec_trigger(NULL, fc->cs, "open", TRUE);
+ if (pool->trigger) exec_trigger(NULL, pool->cs, "open", TRUE);
return 1;
}
+/** Close an existing connection.
+ *
+ * Removes the connection from the list, calls the delete callback to close
+ * the connection, then frees memory allocated to the connection.
+ *
+ * @note Will call the 'close' trigger.
+ * @note Must be called with the mutex held.
+ *
+ * @param [in,out] pool to modify.
+ * @param [in,out] this Connection to delete.
-static void fr_connection_close(fr_connection_pool_t *fc,
+ */
+static void fr_connection_close(fr_connection_pool_t *pool,
fr_connection_t *this)
{
- if (fc->trigger) exec_trigger(NULL, fc->cs, "close", TRUE);
+ if (pool->trigger) exec_trigger(NULL, pool->cs, "close", TRUE);
- rad_assert(this->used == FALSE);
+ rad_assert(this->in_use == FALSE);
- fr_connection_unlink(fc, this);
- fc->delete(fc->ctx, this->connection);
- rad_assert(fc->num > 0);
- fc->num--;
+ fr_connection_unlink(pool, this);
+ pool->delete(pool->ctx, this->connection);
+ rad_assert(pool->num > 0);
+ pool->num--;
free(this);
}
-
-/*
- * Find a connection. Called with the mutex free. If it finds a
- * connection, it returns with the mutex held. Otherwise, it
- * releases the mutex.
+/** Find a connection handle in the connection list
+ *
+ * Walks over the list of connections searching for a specified connection
+ * handle, and returns the first connection that contains that pointer.
+ *
+ * @note Will lock mutex and only release mutex if connection handle
+ * is not found, so will usually return will mutex held.
+ * @note Must be called with the mutex free.
+ *
+ * @param [in] pool to search in.
+ * @param [in] conn handle to search for.
+ * @return the connection containing the specified handle, or NULL if non is
+ * found.
*/
-static fr_connection_t *fr_connection_find(fr_connection_pool_t *fc, void *conn)
+static fr_connection_t *fr_connection_find(fr_connection_pool_t *pool, void *conn)
{
fr_connection_t *this;
- if (!fc || !conn) return NULL;
+ if (!pool || !conn) return NULL;
- pthread_mutex_lock(&fc->mutex);
+ pthread_mutex_lock(&pool->mutex);
/*
* FIXME: This loop could be avoided if we passed a 'void
* **connection' instead. We could use "offsetof" in
* order to find top of the parent structure.
*/
- for (this = fc->head; this != NULL; this = this->next) {
+ for (this = pool->head; this != NULL; this = this->next) {
if (this->connection == conn) return this;
}
- pthread_mutex_unlock(&fc->mutex);
+ pthread_mutex_unlock(&pool->mutex);
return NULL;
}
-
-int fr_connection_del(fr_connection_pool_t *fc, void *conn)
+/** Delete a connection from the connection pool.
+ *
+ * Resolves the connection handle to a connection, then (if found)
+ * closes, unlinks and frees that connection.
+ *
+ * @note Must be called with the mutex free.
+ *
+ * @param [in,out] pool Connection pool to modify.
+ * @param [in] conn to delete.
+ * @return 0 if the connection could not be found, else 1.
+ */
+int fr_connection_del(fr_connection_pool_t *pool, void *conn)
{
fr_connection_t *this;
- this = fr_connection_find(fc, conn);
+ this = fr_connection_find(pool, conn);
if (!this) return 0;
/*
- * If it's used, release it.
+ * If it's in use, release it.
*/
- if (this->used) {
- rad_assert(this->used == TRUE);
- this->used = FALSE;
+ if (this->in_use) {
+ rad_assert(this->in_use == TRUE);
+ this->in_use = FALSE;
- rad_assert(fc->active > 0);
- fc->active--;
+ rad_assert(pool->active > 0);
+ pool->active--;
}
- radlog(L_INFO, "%s: Deleting connection (%i)", fc->log_prefix,
+ radlog(L_INFO, "%s: Deleting connection (%i)", pool->log_prefix,
this->number);
- fr_connection_close(fc, this);
- fr_connection_pool_check(fc);
+ fr_connection_close(pool, this);
+ fr_connection_pool_check(pool);
return 1;
}
-
-void fr_connection_pool_delete(fr_connection_pool_t *fc)
+/** Delete a connection pool
+ *
+ * Closes, unlinks and frees all connections in the connection pool, then frees
+ * all memory used by the connection pool.
+ *
+ * @note Will call the 'stop' trigger.
+ * @note Must be called with the mutex free.
+ *
+ * @param [in,out] pool to delete.
+ */
+void fr_connection_pool_delete(fr_connection_pool_t *pool)
{
fr_connection_t *this, *next;
- if (!fc) return;
+ if (!pool) return;
- DEBUG("%s: Removing connection pool", fc->log_prefix);
+ DEBUG("%s: Removing connection pool", pool->log_prefix);
- pthread_mutex_lock(&fc->mutex);
+ pthread_mutex_lock(&pool->mutex);
- for (this = fc->head; this != NULL; this = next) {
+ for (this = pool->head; this != NULL; this = next) {
next = this->next;
- radlog(L_INFO, "%s: Closing connection (%i)", fc->log_prefix,
+ radlog(L_INFO, "%s: Closing connection (%i)", pool->log_prefix,
this->number);
- fr_connection_close(fc, this);
+ fr_connection_close(pool, this);
}
- if (fc->trigger) exec_trigger(NULL, fc->cs, "stop", TRUE);
+ if (pool->trigger) exec_trigger(NULL, pool->cs, "stop", TRUE);
- rad_assert(fc->head == NULL);
- rad_assert(fc->tail == NULL);
- rad_assert(fc->num == 0);
+ rad_assert(pool->head == NULL);
+ rad_assert(pool->tail == NULL);
+ rad_assert(pool->num == 0);
/*
* In legacy configurations we don't always have a configuration
* section and may initialise the pool struct with defaults
*/
- if (fc->cs) {
- cf_section_parse_free(fc->cs, fc);
+ if (pool->cs) {
+ cf_section_parse_free(pool->cs, pool);
}
- free(fc->log_prefix);
- free(fc);
+ free(pool->log_prefix);
+ free(pool);
}
-
+/** Create a new connection pool
+ *
+ * Allocates structures used by the connection pool, initialises the various
+ * configuration options and counters, and sets the callback functions.
+ *
+ * Will also spawn the number of connections specified by the 'start'
+ * configuration options.
+ *
+ * @note Will call the 'start' trigger.
+ *
+ * @param [in] parent configuration section containing a 'pool' subsection.
+ * @param [in] ctx pointer to pass to callbacks.
+ * @param [in] c Callback to create new connections.
+ * @param [in] a Callback to check the status of connections.
+ * @param [in] d Callback to delete connections.
+ * @return A new connection pool or NULL on error.
+ */
fr_connection_pool_t *fr_connection_pool_init(CONF_SECTION *parent,
void *ctx,
fr_connection_create_t c,
fr_connection_delete_t d)
{
int i, lp_len;
- fr_connection_pool_t *fc;
+ fr_connection_pool_t *pool;
fr_connection_t *this;
CONF_SECTION *modules;
CONF_SECTION *cs;
cs = cf_section_sub_find(parent, "pool");
if (!cs) cs = cf_section_sub_find(parent, "limit");
- fc = rad_malloc(sizeof(*fc));
- memset(fc, 0, sizeof(*fc));
+ pool = rad_malloc(sizeof(*pool));
+ memset(pool, 0, sizeof(*pool));
- fc->cs = cs;
- fc->ctx = ctx;
- fc->create = c;
- fc->alive = a;
- fc->delete = d;
+ pool->cs = cs;
+ pool->ctx = ctx;
+ pool->create = c;
+ pool->alive = a;
+ pool->delete = d;
- fc->head = fc->tail = NULL;
+ pool->head = pool->tail = NULL;
#ifdef HAVE_PTHREAD_H
- pthread_mutex_init(&fc->mutex, NULL);
+ pthread_mutex_init(&pool->mutex, NULL);
#endif
modules = cf_item_parent(cf_sectiontoitem(parent));
}
lp_len = (sizeof(LOG_PREFIX) - 4) + strlen(cs_name1) + strlen(cs_name2);
- fc->log_prefix = rad_malloc(lp_len);
- snprintf(fc->log_prefix, lp_len, LOG_PREFIX, cs_name1,
+ pool->log_prefix = rad_malloc(lp_len);
+ snprintf(pool->log_prefix, lp_len, LOG_PREFIX, cs_name1,
cs_name2);
}
} else { /* not a module configuration */
cs_name1 = cf_section_name1(parent);
- fc->log_prefix = strdup(cs_name1);
+ pool->log_prefix = strdup(cs_name1);
}
- DEBUG("%s: Initialising connection pool", fc->log_prefix);
+ DEBUG("%s: Initialising connection pool", pool->log_prefix);
if (cs) {
- if (cf_section_parse(cs, fc, connection_config) < 0) {
+ if (cf_section_parse(cs, pool, connection_config) < 0) {
goto error;
}
- if (cf_section_sub_find(cs, "trigger")) fc->trigger = TRUE;
+ if (cf_section_sub_find(cs, "trigger")) pool->trigger = TRUE;
} else {
- fc->start = 5;
- fc->min = 5;
- fc->max = 10;
- fc->spare = 3;
- fc->cleanup_delay = 5;
- fc->idle_timeout = 60;
+ pool->start = 5;
+ pool->min = 5;
+ pool->max = 10;
+ pool->spare = 3;
+ pool->cleanup_delay = 5;
+ pool->idle_timeout = 60;
}
/*
* Some simple limits
*/
- if (fc->max > 1024) fc->max = 1024;
- if (fc->start > fc->max) fc->start = fc->max;
- if (fc->spare > (fc->max - fc->min)) {
- fc->spare = fc->max - fc->min;
+ if (pool->max > 1024) pool->max = 1024;
+ if (pool->start > pool->max) pool->start = pool->max;
+ if (pool->spare > (pool->max - pool->min)) {
+ pool->spare = pool->max - pool->min;
}
- if ((fc->lifetime > 0) && (fc->idle_timeout > fc->lifetime)) {
- fc->idle_timeout = 0;
+ if ((pool->lifetime > 0) && (pool->idle_timeout > pool->lifetime)) {
+ pool->idle_timeout = 0;
}
/*
* Create all of the connections, unless the admin says
* not to.
*/
- for (i = 0; i < fc->start; i++) {
- this = fr_connection_spawn(fc, now);
+ for (i = 0; i < pool->start; i++) {
+ this = fr_connection_spawn(pool, now);
if (!this) {
error:
- fr_connection_pool_delete(fc);
+ fr_connection_pool_delete(pool);
return NULL;
}
}
- if (fc->trigger) exec_trigger(NULL, fc->cs, "start", TRUE);
+ if (pool->trigger) exec_trigger(NULL, pool->cs, "start", TRUE);
- return fc;
+ return pool;
}
-/*
- * Called with the mutex lock held.
+/** Check whether a connection needs to be removed from the pool
+ *
+ * Will verify that the connection is within idle_timeout, max_uses, and
+ * lifetime values. If it is not, the connection will be closed.
+ *
+ * @note Will only close connections not in use.
+ * @note Must be called with the mutex held.
+ *
+ * @param [in,out] pool
+ * @param [in,out] this Connection to manage.
+ * @param [in] now Current time.
+ * @return 0 if the connection was closed, otherwise 1.
*/
-static int fr_connection_manage(fr_connection_pool_t *fc,
+static int fr_connection_manage(fr_connection_pool_t *pool,
fr_connection_t *this,
time_t now)
{
- rad_assert(fc != NULL);
+ rad_assert(pool != NULL);
rad_assert(this != NULL);
/*
* Don't terminated in-use connections
*/
- if (this->used) return 1;
+ if (this->in_use) return 1;
- if ((fc->max_uses > 0) &&
- (this->num_uses >= fc->max_uses)) {
+ if ((pool->max_uses > 0) &&
+ (this->num_uses >= pool->max_uses)) {
DEBUG("%s: Closing expired connection (%i): Hit max_uses limit",
- fc->log_prefix, this->number);
+ pool->log_prefix, this->number);
do_delete:
- if ((fc->num <= fc->min) &&
- (fc->last_complained < now)) {
+ if ((pool->num <= pool->min) &&
+ (pool->last_complained < now)) {
radlog(L_INFO, "%s: WARNING: You probably need to "
- "lower \"min\"", fc->log_prefix);
+ "lower \"min\"", pool->log_prefix);
- fc->last_complained = now;
+ pool->last_complained = now;
}
- fr_connection_close(fc, this);
+ fr_connection_close(pool, this);
return 0;
}
- if ((fc->lifetime > 0) &&
- ((this->start + fc->lifetime) < now)) {
- DEBUG("%s: Closing expired connection (%i) ", fc->log_prefix,
+ if ((pool->lifetime > 0) &&
+ ((this->start + pool->lifetime) < now)) {
+ DEBUG("%s: Closing expired connection (%i) ", pool->log_prefix,
this->number);
goto do_delete;
}
- if ((fc->idle_timeout > 0) &&
- ((this->last_used + fc->idle_timeout) < now)) {
+ if ((pool->idle_timeout > 0) &&
+ ((this->last_used + pool->idle_timeout) < now)) {
radlog(L_INFO, "%s: Closing connection (%i): Hit idle_timeout, "
- "was idle for %u seconds", fc->log_prefix, this->number,
+ "was idle for %u seconds", pool->log_prefix, this->number,
(int) (now - this->last_used));
goto do_delete;
}
}
-/*
- * Called with the mutex held. Releases it.
+/** Check whether any connections needs to be removed from the pool
+ *
+ * Maintains the number of connections in the pool as per the configuration
+ * parameters for the connection pool.
+ *
+ * @note Will only run checks the first time it's called in a given second,
+ * to throttle connection spawning/closing.
+ * @note Will only close connections not in use.
+ * @note Must be called with the mutex held, will release mutex before
+ * returning.
+ *
+ * @param [in,out] pool to manage.
+ * @return 1
*/
-static int fr_connection_pool_check(fr_connection_pool_t *fc)
+static int fr_connection_pool_check(fr_connection_pool_t *pool)
{
int spare, spawn;
time_t now = time(NULL);
fr_connection_t *this, *next;
- if (fc->last_checked == now) {
- pthread_mutex_unlock(&fc->mutex);
+ if (pool->last_checked == now) {
+ pthread_mutex_unlock(&pool->mutex);
return 1;
}
- spare = fc->num - fc->active;
+ spare = pool->num - pool->active;
spawn = 0;
- if ((fc->num < fc->max) && (spare < fc->spare)) {
- spawn = fc->spare - spare;
- if ((spawn + fc->num) > fc->max) {
- spawn = fc->max - fc->num;
+ if ((pool->num < pool->max) && (spare < pool->spare)) {
+ spawn = pool->spare - spare;
+ if ((spawn + pool->num) > pool->max) {
+ spawn = pool->max - pool->num;
}
- if (fc->spawning) spawn = 0;
+ if (pool->spawning) spawn = 0;
if (spawn) {
- pthread_mutex_unlock(&fc->mutex);
- fr_connection_spawn(fc, now); /* ignore return code */
- pthread_mutex_lock(&fc->mutex);
+ pthread_mutex_unlock(&pool->mutex);
+ fr_connection_spawn(pool, now); /* ignore return code */
+ pthread_mutex_lock(&pool->mutex);
}
}
* are too many spare ones. Close the one which has been
* idle for the longest.
*/
- if ((now >= (fc->last_spawned + fc->cleanup_delay)) &&
- (spare > fc->spare)) {
+ if ((now >= (pool->last_spawned + pool->cleanup_delay)) &&
+ (spare > pool->spare)) {
fr_connection_t *idle;
idle = NULL;
- for (this = fc->tail; this != NULL; this = this->prev) {
- if (this->used) continue;
+ for (this = pool->tail; this != NULL; this = this->prev) {
+ if (this->in_use) continue;
if (!idle ||
(this->last_used < idle->last_used)) {
rad_assert(idle != NULL);
radlog(L_INFO, "%s: Closing connection (%i): Too many "
- "free connections (%d > %d)", fc->log_prefix,
- idle->number, spare, fc->spare);
- fr_connection_close(fc, idle);
+ "free connections (%d > %d)", pool->log_prefix,
+ idle->number, spare, pool->spare);
+ fr_connection_close(pool, idle);
}
/*
* Pass over all of the connections in the pool, limiting
* lifetime, idle time, max requests, etc.
*/
- for (this = fc->head; this != NULL; this = next) {
+ for (this = pool->head; this != NULL; this = next) {
next = this->next;
- fr_connection_manage(fc, this, now);
+ fr_connection_manage(pool, this, now);
}
- fc->last_checked = now;
- pthread_mutex_unlock(&fc->mutex);
+ pool->last_checked = now;
+ pthread_mutex_unlock(&pool->mutex);
return 1;
}
-
-int fr_connection_check(fr_connection_pool_t *fc, void *conn)
+/** Trigger connection check for a given connection or all connections
+ *
+ * If conn is not NULL then we call fr_connection_manage on the connection.
+ * If conn is NULL we call fr_connection_pool_check on the pool.
+ *
+ * @note Only connections that are not in use will be closed.
+ *
+ * @see fr_connection_manage
+ * @see fr_connection_pool_check
+ * @param [in,out] pool to manage.
+ * @param [in,out] conn to check.
+ * @return 0 if the connection was closed, else 1.
+ */
+int fr_connection_check(fr_connection_pool_t *pool, void *conn)
{
fr_connection_t *this;
time_t now;
+ int ret = 1;
- if (!fc) return 1;
+ if (!pool) return 1;
now = time(NULL);
- pthread_mutex_lock(&fc->mutex);
+ pthread_mutex_lock(&pool->mutex);
- if (!conn) return fr_connection_pool_check(fc);
+ if (!conn) return fr_connection_pool_check(pool);
- for (this = fc->head; this != NULL; this = this->next) {
+ for (this = pool->head; this != NULL; this = this->next) {
if (this->connection == conn) {
- fr_connection_manage(fc, conn, now);
+ ret = fr_connection_manage(pool, conn, now);
break;
}
}
- pthread_mutex_unlock(&fc->mutex);
+ pthread_mutex_unlock(&pool->mutex);
- return 1;
+ return ret;
}
-
-void *fr_connection_get(fr_connection_pool_t *fc)
+/** Reserve a connection in the connection pool
+ *
+ * Will attempt to find an unused connection in the connection pool, if one is
+ * found, will mark it as in in use increment the number of active connections
+ * and return the connection handle.
+ *
+ * If no free connections are found will attempt to spawn a new one, conditional
+ * on a connection spawning not already being in progress, and not being at the
+ * 'max' connection limit.
+ *
+ * @note fr_connection_release must be called once the caller has finished
+ * using the connection.
+ *
+ * @see fr_connection_release
+ * @param [in,out] pool to reserve the connection from.
+ * @return a pointer to the connection handle, or NULL on error.
+ */
+void *fr_connection_get(fr_connection_pool_t *pool)
{
time_t now;
fr_connection_t *this, *next;
- if (!fc) return NULL;
+ if (!pool) return NULL;
- pthread_mutex_lock(&fc->mutex);
+ pthread_mutex_lock(&pool->mutex);
now = time(NULL);
- for (this = fc->head; this != NULL; this = next) {
+ for (this = pool->head; this != NULL; this = next) {
next = this->next;
- if (!this->used) goto do_return;
+ if (!this->in_use) goto do_return;
}
- if (fc->num == fc->max) {
+ if (pool->num == pool->max) {
int complain = FALSE;
/*
* Rate-limit complaints.
*/
- if (fc->last_at_max != now) {
+ if (pool->last_at_max != now) {
complain = TRUE;
- fc->last_at_max = now;
+ pool->last_at_max = now;
}
- pthread_mutex_unlock(&fc->mutex);
+ pthread_mutex_unlock(&pool->mutex);
if (complain) {
radlog(L_ERR, "%s: No connections available and at max "
- "connection limit", fc->log_prefix);
+ "connection limit", pool->log_prefix);
}
return NULL;
}
- pthread_mutex_unlock(&fc->mutex);
- this = fr_connection_spawn(fc, now);
+ pthread_mutex_unlock(&pool->mutex);
+ this = fr_connection_spawn(pool, now);
if (!this) return NULL;
- pthread_mutex_lock(&fc->mutex);
+ pthread_mutex_lock(&pool->mutex);
do_return:
- fc->active++;
+ pool->active++;
this->num_uses++;
this->last_used = now;
- this->used = TRUE;
+ this->in_use = TRUE;
- pthread_mutex_unlock(&fc->mutex);
+ pthread_mutex_unlock(&pool->mutex);
- DEBUG("%s: Reserved connection (%i)", fc->log_prefix, this->number);
+ DEBUG("%s: Reserved connection (%i)", pool->log_prefix, this->number);
return this->connection;
}
-
-void fr_connection_release(fr_connection_pool_t *fc, void *conn)
+/** Release a connection
+ *
+ * Will mark a connection as unused and decrement the number of active
+ * connections.
+ *
+ * @see fr_connection_get
+ * @param [in,out] pool to release the connection in.
+ * @param [in,out] conn to release.
+ */
+void fr_connection_release(fr_connection_pool_t *pool, void *conn)
{
fr_connection_t *this;
- this = fr_connection_find(fc, conn);
+ this = fr_connection_find(pool, conn);
if (!this) return;
- rad_assert(this->used == TRUE);
- this->used = FALSE;
+ rad_assert(this->in_use == TRUE);
+ this->in_use = FALSE;
/*
* Put it at the head of the list, so
* that it will get re-used quickly.
*/
- if (this != fc->head) {
- fr_connection_unlink(fc, this);
- fr_connection_link(fc, this);
+ if (this != pool->head) {
+ fr_connection_unlink(pool, this);
+ fr_connection_link(pool, this);
}
- rad_assert(fc->active > 0);
- fc->active--;
+ rad_assert(pool->active > 0);
+ pool->active--;
- DEBUG("%s: Released connection (%i)", fc->log_prefix, this->number);
+ DEBUG("%s: Released connection (%i)", pool->log_prefix, this->number);
/*
* We mirror the "spawn on get" functionality by having
* "delete on release". If there are too many spare
* connections, go manage the pool && clean some up.
*/
- fr_connection_pool_check(fc);
+ fr_connection_pool_check(pool);
}
-
-void *fr_connection_reconnect(fr_connection_pool_t *fc, void *conn)
+/** Reconnect a suspected inviable connection
+ *
+ * This should be called by the module if it suspects that a connection is
+ * not viable (e.g. the server has closed it).
+ *
+ * Will attempt to create a new connection handle using the create callback,
+ * and if this is successful the new handle will be assigned to the existing
+ * pool connection.
+ *
+ * If this is not successful, the connection will be removed from the pool.
+ *
+ * When implementing a module that uses the connection pool API, it is advisable
+ * to pass a pointer to the pointer to the handle (void **conn)
+ * to all functions which may call reconnect. This is so that if a new handle
+ * is created and returned, the handle pointer can be updated up the callstack,
+ * and a function higher up the stack doesn't attempt to use a now invalid
+ * connection handle.
+ *
+ * @warning After calling reconnect the caller *MUST NOT* attempt to use
+ * the old handle in any other operations, as its memory will have been freed.
+ *
+ * @see fr_connection_get
+ * @param [in,out] pool to reconnect the connection in.
+ * @param [in,out] conn to reconnect.
+ * @return ew connection handle if successful else NULL.
+ */
+void *fr_connection_reconnect(fr_connection_pool_t *pool, void *conn)
{
void *new_conn;
fr_connection_t *this;
int conn_number;
- if (!fc || !conn) return NULL;
+ if (!pool || !conn) return NULL;
- this = fr_connection_find(fc, conn);
+ this = fr_connection_find(pool, conn);
if (!this) return NULL;
conn_number = this->number;
- rad_assert(this->used == TRUE);
+ rad_assert(this->in_use == TRUE);
- DEBUG("%s: Reconnecting (%i)", fc->log_prefix, conn_number);
+ DEBUG("%s: Reconnecting (%i)", pool->log_prefix, conn_number);
- new_conn = fc->create(fc->ctx);
+ new_conn = pool->create(pool->ctx);
if (!new_conn) {
time_t now = time(NULL);
- if (fc->last_complained == now) {
+ if (pool->last_complained == now) {
now = 0;
} else {
- fc->last_complained = now;
+ pool->last_complained = now;
}
- this->used = FALSE;
+ this->in_use = FALSE;
- rad_assert(fc->active > 0);
- fc->active--;
+ rad_assert(pool->active > 0);
+ pool->active--;
- fr_connection_close(fc, this);
- pthread_mutex_unlock(&fc->mutex);
+ fr_connection_close(pool, this);
+ pthread_mutex_unlock(&pool->mutex);
/*
* Can't create a new socket.
* Try grabbing a pre-existing one.
*/
- new_conn = fr_connection_get(fc);
+ new_conn = fr_connection_get(pool);
if (new_conn) return new_conn;
if (!now) return NULL;
radlog(L_ERR, "%s: Failed to reconnect (%i), and no other "
- "connections available", fc->log_prefix, conn_number);
+ "connections available", pool->log_prefix, conn_number);
return NULL;
}
- fc->delete(fc->ctx, conn);
+ pool->delete(pool->ctx, conn);
this->connection = new_conn;
- pthread_mutex_unlock(&fc->mutex);
+ pthread_mutex_unlock(&pool->mutex);
return new_conn;
}
projects / thirdparty / freeradius-server.git / commitdiff
