session BUGFIX proper ps locking error cleanup
diff --git a/src/session_server.c b/src/session_server.c
index 6473fe2..fc84319 100644
--- a/src/session_server.c
+++ b/src/session_server.c
@@ -525,11 +525,46 @@
return msgtype;
}
+static void
+nc_ps_queue_remove_id(struct nc_pollsession *ps, uint8_t id)
+{
+ uint8_t i, found = 0;
+
+ for (i = 0; i < ps->queue_len; ++i) {
+ /* idx round buffer adjust */
+ if (ps->queue_begin + i == NC_PS_QUEUE_SIZE) {
+ i = -ps->queue_begin;
+ }
+
+ if (found) {
+ /* move the value back one place */
+ if (ps->queue[ps->queue_begin + i] == id) {
+ /* another equal value, simply cannot be */
+ ERRINT;
+ }
+
+ if (ps->queue_begin + i == 0) {
+ ps->queue[NC_PS_QUEUE_SIZE - 1] = ps->queue[ps->queue_begin + i];
+ } else {
+ ps->queue[ps->queue_begin + i - 1] = ps->queue[ps->queue_begin + i];
+ }
+ } else if (ps->queue[ps->queue_begin + i] == id) {
+ /* found our id, there can be no more equal valid values */
+ found = 1;
+ }
+ }
+
+ if (!found) {
+ ERRINT;
+ }
+ --ps->queue_len;
+}
+
int
-nc_ps_lock(struct nc_pollsession *ps)
+nc_ps_lock(struct nc_pollsession *ps, uint8_t *id)
{
int ret;
- uint8_t our_id, queue_last;
+ uint8_t queue_last;
struct timespec ts;
nc_gettimespec(&ts);
@@ -548,9 +583,9 @@
if (queue_last > NC_PS_QUEUE_SIZE - 1) {
queue_last -= NC_PS_QUEUE_SIZE;
}
- our_id = ps->queue[queue_last] + 1;
+ *id = ps->queue[queue_last] + 1;
} else {
- our_id = 0;
+ *id = 0;
}
/* add ourselves into the queue */
@@ -563,10 +598,10 @@
if (queue_last > NC_PS_QUEUE_SIZE - 1) {
queue_last -= NC_PS_QUEUE_SIZE;
}
- ps->queue[queue_last] = our_id;
+ ps->queue[queue_last] = *id;
/* is it our turn? */
- while (ps->queue[ps->queue_begin] != our_id) {
+ while (ps->queue[ps->queue_begin] != *id) {
nc_gettimespec(&ts);
ts.tv_sec += NC_READ_TIMEOUT;
@@ -574,8 +609,8 @@
if (ret) {
ERR("Failed to wait for a pollsession condition (%s).", strerror(ret));
/* remove ourselves from the queue */
- ps->queue_begin = (ps->queue_begin < NC_PS_QUEUE_SIZE - 1 ? ps->queue_begin + 1 : 0);
- --ps->queue_len;
+ nc_ps_queue_remove_id(ps, *id);
+ pthread_mutex_unlock(&ps->lock);
return -1;
}
}
@@ -587,7 +622,7 @@
}
int
-nc_ps_unlock(struct nc_pollsession *ps)
+nc_ps_unlock(struct nc_pollsession *ps, uint8_t id)
{
int ret;
struct timespec ts;
@@ -602,9 +637,14 @@
ret = -1;
}
+ /* we must be the first, it was our turn after all, right? */
+ if (ps->queue[ps->queue_begin] != id) {
+ ERRINT;
+ return -1;
+ }
+
/* remove ourselves from the queue */
- ps->queue_begin = (ps->queue_begin < NC_PS_QUEUE_SIZE - 1 ? ps->queue_begin + 1 : 0);
- --ps->queue_len;
+ nc_ps_queue_remove_id(ps, id);
/* broadcast to all other threads that the queue moved */
pthread_cond_broadcast(&ps->cond);
@@ -655,6 +695,8 @@
API int
nc_ps_add_session(struct nc_pollsession *ps, struct nc_session *session)
{
+ uint8_t q_id;
+
if (!ps) {
ERRARG("ps");
return -1;
@@ -664,7 +706,7 @@
}
/* LOCK */
- if (nc_ps_lock(ps)) {
+ if (nc_ps_lock(ps, &q_id)) {
return -1;
}
@@ -674,7 +716,7 @@
if (!ps->pfds || !ps->sessions) {
ERRMEM;
/* UNLOCK */
- nc_ps_unlock(ps);
+ nc_ps_unlock(ps, q_id);
return -1;
}
@@ -698,7 +740,7 @@
default:
ERRINT;
/* UNLOCK */
- nc_ps_unlock(ps);
+ nc_ps_unlock(ps, q_id);
return -1;
}
ps->pfds[ps->session_count - 1].events = POLLIN;
@@ -706,7 +748,7 @@
ps->sessions[ps->session_count - 1] = session;
/* UNLOCK */
- return nc_ps_unlock(ps);
+ return nc_ps_unlock(ps, q_id);
}
static int
@@ -741,6 +783,7 @@
API int
nc_ps_del_session(struct nc_pollsession *ps, struct nc_session *session)
{
+ uint8_t q_id;
int ret, ret2;
if (!ps) {
@@ -752,14 +795,14 @@
}
/* LOCK */
- if (nc_ps_lock(ps)) {
+ if (nc_ps_lock(ps, &q_id)) {
return -1;
}
ret = _nc_ps_del_session(ps, session, -1);
/* UNLOCK */
- ret2 = nc_ps_unlock(ps);
+ ret2 = nc_ps_unlock(ps, q_id);
return (ret || ret2 ? -1 : 0);
}
@@ -767,6 +810,7 @@
API uint16_t
nc_ps_session_count(struct nc_pollsession *ps)
{
+ uint8_t q_id;
uint16_t count;
if (!ps) {
@@ -775,14 +819,14 @@
}
/* LOCK */
- if (nc_ps_lock(ps)) {
+ if (nc_ps_lock(ps, &q_id)) {
return -1;
}
count = ps->session_count;
/* UNLOCK */
- nc_ps_unlock(ps);
+ nc_ps_unlock(ps, q_id);
return count;
}
@@ -919,6 +963,7 @@
nc_ps_poll(struct nc_pollsession *ps, int timeout, struct nc_session **session)
{
int ret;
+ uint8_t q_id;
uint16_t i;
time_t cur_time;
struct nc_session *cur_session;
@@ -932,7 +977,7 @@
cur_time = time(NULL);
/* LOCK */
- if (nc_ps_lock(ps)) {
+ if (nc_ps_lock(ps, &q_id)) {
return NC_PSPOLL_ERROR;
}
@@ -1111,13 +1156,14 @@
finish:
/* UNLOCK */
- nc_ps_unlock(ps);
+ nc_ps_unlock(ps, q_id);
return ret;
}
API void
nc_ps_clear(struct nc_pollsession *ps, int all, void (*data_free)(void *))
{
+ uint8_t q_id;
uint16_t i;
struct nc_session *session;
@@ -1127,7 +1173,7 @@
}
/* LOCK */
- if (nc_ps_lock(ps)) {
+ if (nc_ps_lock(ps, &q_id)) {
return;
}
@@ -1154,7 +1200,7 @@
}
/* UNLOCK */
- nc_ps_unlock(ps);
+ nc_ps_unlock(ps, q_id);
}
#if defined(NC_ENABLED_SSH) || defined(NC_ENABLED_TLS)