#include <assert.h>
#include "apu.h"
#include "apr_reslist.h"
#include "apr_errno.h"
#include "apr_strings.h"
#include "apr_thread_mutex.h"
#include "apr_thread_cond.h"
#include "apr_ring.h"
struct apr_res_t {
apr_time_t freed;
void *opaque;
APR_RING_ENTRY(apr_res_t) link;
};
typedef struct apr_res_t apr_res_t;
APR_RING_HEAD(apr_resring_t, apr_res_t);
typedef struct apr_resring_t apr_resring_t;
struct apr_reslist_t {
apr_pool_t *pool;
int ntotal;
int nidle;
int min;
int smax;
int hmax;
apr_interval_time_t ttl;
apr_interval_time_t timeout;
apr_reslist_constructor constructor;
apr_reslist_destructor destructor;
void *params;
apr_resring_t avail_list;
apr_resring_t free_list;
#if APR_HAS_THREADS
apr_thread_mutex_t *listlock;
apr_thread_cond_t *avail;
#endif
};
static apr_res_t *pop_resource(apr_reslist_t *reslist)
{
apr_res_t *res;
res = APR_RING_FIRST(&reslist->avail_list);
APR_RING_REMOVE(res, link);
reslist->nidle--;
return res;
}
static void push_resource(apr_reslist_t *reslist, apr_res_t *resource)
{
APR_RING_INSERT_HEAD(&reslist->avail_list, resource, apr_res_t, link);
resource->freed = apr_time_now();
reslist->nidle++;
}
static apr_res_t *get_container(apr_reslist_t *reslist)
{
apr_res_t *res;
if (!APR_RING_EMPTY(&reslist->free_list, apr_res_t, link)) {
res = APR_RING_FIRST(&reslist->free_list);
APR_RING_REMOVE(res, link);
}
else
res = apr_pcalloc(reslist->pool, sizeof(*res));
return res;
}
static void free_container(apr_reslist_t *reslist, apr_res_t *container)
{
APR_RING_INSERT_TAIL(&reslist->free_list, container, apr_res_t, link);
}
static apr_status_t create_resource(apr_reslist_t *reslist, apr_res_t **ret_res)
{
apr_status_t rv;
apr_res_t *res;
res = get_container(reslist);
rv = reslist->constructor(&res->opaque, reslist->params, reslist->pool);
*ret_res = res;
return rv;
}
static apr_status_t destroy_resource(apr_reslist_t *reslist, apr_res_t *res)
{
return reslist->destructor(res->opaque, reslist->params, reslist->pool);
}
static apr_status_t reslist_cleanup(void *data_)
{
apr_status_t rv = APR_SUCCESS;
apr_reslist_t *rl = data_;
apr_res_t *res;
#if APR_HAS_THREADS
apr_thread_mutex_lock(rl->listlock);
#endif
while (rl->nidle > 0) {
apr_status_t rv1;
res = pop_resource(rl);
rl->ntotal--;
rv1 = destroy_resource(rl, res);
if (rv1 != APR_SUCCESS) {
rv = rv1;
}
free_container(rl, res);
}
assert(rl->nidle == 0);
assert(rl->ntotal == 0);
#if APR_HAS_THREADS
apr_thread_mutex_unlock(rl->listlock);
apr_thread_mutex_destroy(rl->listlock);
apr_thread_cond_destroy(rl->avail);
#endif
return rv;
}
APU_DECLARE(apr_status_t) apr_reslist_maintain(apr_reslist_t *reslist)
{
apr_time_t now;
apr_status_t rv;
apr_res_t *res;
int created_one = 0;
#if APR_HAS_THREADS
apr_thread_mutex_lock(reslist->listlock);
#endif
while (reslist->nidle < reslist->min && reslist->ntotal < reslist->hmax) {
rv = create_resource(reslist, &res);
if (rv != APR_SUCCESS) {
free_container(reslist, res);
#if APR_HAS_THREADS
apr_thread_mutex_unlock(reslist->listlock);
#endif
return rv;
}
push_resource(reslist, res);
reslist->ntotal++;
#if APR_HAS_THREADS
rv = apr_thread_cond_signal(reslist->avail);
if (rv != APR_SUCCESS) {
apr_thread_mutex_unlock(reslist->listlock);
return rv;
}
#endif
created_one++;
}
if (created_one) {
#if APR_HAS_THREADS
apr_thread_mutex_unlock(reslist->listlock);
#endif
return APR_SUCCESS;
}
now = apr_time_now();
while (reslist->nidle > reslist->smax && reslist->nidle > 0) {
res = APR_RING_LAST(&reslist->avail_list);
if (now - res->freed < reslist->ttl) {
break;
}
APR_RING_REMOVE(res, link);
reslist->nidle--;
reslist->ntotal--;
rv = destroy_resource(reslist, res);
free_container(reslist, res);
if (rv != APR_SUCCESS) {
#if APR_HAS_THREADS
apr_thread_mutex_unlock(reslist->listlock);
#endif
return rv;
}
}
#if APR_HAS_THREADS
apr_thread_mutex_unlock(reslist->listlock);
#endif
return APR_SUCCESS;
}
APU_DECLARE(apr_status_t) apr_reslist_create(apr_reslist_t **reslist,
int min, int smax, int hmax,
apr_interval_time_t ttl,
apr_reslist_constructor con,
apr_reslist_destructor de,
void *params,
apr_pool_t *pool)
{
apr_status_t rv;
apr_reslist_t *rl;
if (min < 0 || min > smax || min > hmax || smax > hmax || hmax == 0 ||
ttl < 0) {
return APR_EINVAL;
}
#if !APR_HAS_THREADS
if (min > 0) {
min = 1;
}
if (smax > 0) {
smax = 1;
}
hmax = 1;
#endif
rl = apr_pcalloc(pool, sizeof(*rl));
rl->pool = pool;
rl->min = min;
rl->smax = smax;
rl->hmax = hmax;
rl->ttl = ttl;
rl->constructor = con;
rl->destructor = de;
rl->params = params;
APR_RING_INIT(&rl->avail_list, apr_res_t, link);
APR_RING_INIT(&rl->free_list, apr_res_t, link);
#if APR_HAS_THREADS
rv = apr_thread_mutex_create(&rl->listlock, APR_THREAD_MUTEX_DEFAULT,
pool);
if (rv != APR_SUCCESS) {
return rv;
}
rv = apr_thread_cond_create(&rl->avail, pool);
if (rv != APR_SUCCESS) {
return rv;
}
#endif
rv = apr_reslist_maintain(rl);
if (rv != APR_SUCCESS) {
reslist_cleanup(rl);
return rv;
}
apr_pool_cleanup_register(rl->pool, rl, reslist_cleanup,
apr_pool_cleanup_null);
*reslist = rl;
return APR_SUCCESS;
}
APU_DECLARE(apr_status_t) apr_reslist_destroy(apr_reslist_t *reslist)
{
return apr_pool_cleanup_run(reslist->pool, reslist, reslist_cleanup);
}
APU_DECLARE(apr_status_t) apr_reslist_acquire(apr_reslist_t *reslist,
void **resource)
{
apr_status_t rv;
apr_res_t *res;
apr_time_t now;
#if APR_HAS_THREADS
apr_thread_mutex_lock(reslist->listlock);
#endif
now = apr_time_now();
while (reslist->nidle > 0) {
res = pop_resource(reslist);
if (reslist->ttl && (now - res->freed >= reslist->ttl)) {
reslist->ntotal--;
rv = destroy_resource(reslist, res);
free_container(reslist, res);
if (rv != APR_SUCCESS) {
#if APR_HAS_THREADS
apr_thread_mutex_unlock(reslist->listlock);
#endif
return rv;
}
continue;
}
*resource = res->opaque;
free_container(reslist, res);
#if APR_HAS_THREADS
apr_thread_mutex_unlock(reslist->listlock);
#endif
return APR_SUCCESS;
}
while (reslist->ntotal >= reslist->hmax && reslist->nidle <= 0) {
#if APR_HAS_THREADS
if (reslist->timeout) {
if ((rv = apr_thread_cond_timedwait(reslist->avail,
reslist->listlock, reslist->timeout)) != APR_SUCCESS) {
apr_thread_mutex_unlock(reslist->listlock);
return rv;
}
}
else {
apr_thread_cond_wait(reslist->avail, reslist->listlock);
}
#else
return APR_EAGAIN;
#endif
}
if (reslist->nidle > 0) {
res = pop_resource(reslist);
*resource = res->opaque;
free_container(reslist, res);
#if APR_HAS_THREADS
apr_thread_mutex_unlock(reslist->listlock);
#endif
return APR_SUCCESS;
}
else {
rv = create_resource(reslist, &res);
if (rv == APR_SUCCESS) {
reslist->ntotal++;
*resource = res->opaque;
}
free_container(reslist, res);
#if APR_HAS_THREADS
apr_thread_mutex_unlock(reslist->listlock);
#endif
return rv;
}
}
APU_DECLARE(apr_status_t) apr_reslist_release(apr_reslist_t *reslist,
void *resource)
{
apr_res_t *res;
#if APR_HAS_THREADS
apr_thread_mutex_lock(reslist->listlock);
#endif
res = get_container(reslist);
res->opaque = resource;
push_resource(reslist, res);
#if APR_HAS_THREADS
apr_thread_cond_signal(reslist->avail);
apr_thread_mutex_unlock(reslist->listlock);
#endif
return apr_reslist_maintain(reslist);
}
APU_DECLARE(void) apr_reslist_timeout_set(apr_reslist_t *reslist,
apr_interval_time_t timeout)
{
reslist->timeout = timeout;
}
APU_DECLARE(apr_uint32_t) apr_reslist_acquired_count(apr_reslist_t *reslist)
{
apr_uint32_t count;
#if APR_HAS_THREADS
apr_thread_mutex_lock(reslist->listlock);
#endif
count = reslist->ntotal - reslist->nidle;
#if APR_HAS_THREADS
apr_thread_mutex_unlock(reslist->listlock);
#endif
return count;
}
APU_DECLARE(apr_status_t) apr_reslist_invalidate(apr_reslist_t *reslist,
void *resource)
{
apr_status_t ret;
#if APR_HAS_THREADS
apr_thread_mutex_lock(reslist->listlock);
#endif
ret = reslist->destructor(resource, reslist->params, reslist->pool);
reslist->ntotal--;
#if APR_HAS_THREADS
apr_thread_cond_signal(reslist->avail);
apr_thread_mutex_unlock(reslist->listlock);
#endif
return ret;
}
APU_DECLARE(void) apr_reslist_cleanup_order_set(apr_reslist_t *rl,
apr_uint32_t mode)
{
apr_pool_cleanup_kill(rl->pool, rl, reslist_cleanup);
if (mode == APR_RESLIST_CLEANUP_FIRST)
apr_pool_pre_cleanup_register(rl->pool, rl, reslist_cleanup);
else
apr_pool_cleanup_register(rl->pool, rl, reslist_cleanup,
apr_pool_cleanup_null);
}