lib: dev: Provide a set of fds to flow_select

The flow_select call now takes as a parameter a flow_set_t, which
specifies a set of flow descriptors that will unblock the select call
when an SDU for one of them arrives. The select call has been moved to
its own header.

2 files changed, 165 insertions, 14 deletions

diff --git a/src/lib/dev.c b/src/lib/dev.c
index b7de921d..64327dd3 100644
--- a/src/lib/dev.c
+++ b/src/lib/dev.c
@@ -28,9 +28,16 @@
 #include <ouroboros/shm_rdrbuff.h>
 #include <ouroboros/shm_ap_rbuff.h>
 #include <ouroboros/utils.h>
+#include <ouroboros/select.h>
 
 #include <stdlib.h>
 #include <string.h>
+#include <stdio.h>
+
+struct flow_set {
+        bool b[IRMD_MAX_FLOWS];
+        pthread_rwlock_t lock;
+};
 
 struct flow {
         struct shm_ap_rbuff * rb;
@@ -577,14 +584,6 @@ ssize_t flow_write(int fd, void * buf, size_t count)
         return 0;
 }
 
-int flow_select(const struct timespec * timeout)
-{
-        int port_id = shm_ap_rbuff_peek_b(ai->rb, timeout);
-        if (port_id < 0)
-                return port_id;
-        return ai->ports[port_id];
-}
-
 ssize_t flow_read(int fd, void * buf, size_t count)
 {
         int idx = -1;
@@ -638,3 +637,79 @@ ssize_t flow_read(int fd, void * buf, size_t count)
 
         return n;
 }
+
+/* select functions */
+
+struct flow_set * flow_set_create()
+{
+        struct flow_set * set = malloc(sizeof(*set));
+        if (set == NULL)
+                return NULL;
+
+        if (pthread_rwlock_init(&set->lock, NULL)) {
+                free(set);
+                return NULL;
+        }
+
+        memset(&set->b, 0, sizeof(set->b));
+
+        return set;
+}
+
+void flow_set_zero(struct flow_set * set)
+{
+        pthread_rwlock_wrlock(&set->lock);
+        memset(&set->b, 0, sizeof(set->b));
+        pthread_rwlock_unlock(&set->lock);
+}
+
+void flow_set_add(struct flow_set * set, int fd)
+{
+        pthread_rwlock_wrlock(&set->lock);
+        set->b[ai->flows[fd].port_id] = true;
+        pthread_rwlock_unlock(&set->lock);
+}
+
+void flow_set_del(struct flow_set * set, int fd)
+{
+        pthread_rwlock_wrlock(&set->lock);
+        set->b[ai->flows[fd].port_id] = false;
+        pthread_rwlock_unlock(&set->lock);
+}
+
+bool flow_set_has(struct flow_set * set, int fd)
+{
+        bool ret;
+        pthread_rwlock_rdlock(&set->lock);
+        ret = set->b[ai->flows[fd].port_id];
+        pthread_rwlock_unlock(&set->lock);
+        return ret;
+}
+
+void flow_set_destroy(struct flow_set * set)
+{
+        pthread_rwlock_destroy(&set->lock);
+        free(set);
+}
+
+static void flow_set_cpy(bool * dst, struct flow_set * src)
+{
+        pthread_rwlock_rdlock(&src->lock);
+        memcpy(dst, src->b, IRMD_MAX_FLOWS);
+        pthread_rwlock_unlock(&src->lock);
+}
+
+int flow_select(struct flow_set * set, const struct timespec * timeout)
+{
+        int port_id;
+        bool b[IRMD_MAX_FLOWS];
+        if (set == NULL) {
+                port_id = shm_ap_rbuff_peek_b(ai->rb, NULL, timeout);
+        } else {
+                flow_set_cpy(b, set);
+                port_id = shm_ap_rbuff_peek_b(ai->rb, (bool *) b, timeout);
+        }
+        if (port_id < 0)
+                return port_id;
+        return ai->ports[port_id];
+}
diff --git a/src/lib/shm_ap_rbuff.c b/src/lib/shm_ap_rbuff.c
index 6cc9590e..e6665362 100644
--- a/src/lib/shm_ap_rbuff.c
+++ b/src/lib/shm_ap_rbuff.c
@@ -348,15 +348,15 @@ int shm_ap_rbuff_peek_idx(struct shm_ap_rbuff * rb)
                 return -1;
         }
 
-        ret = (rb->shm_base + *rb->ptr_tail)->index;
+        ret = tail_el_ptr(rb)->index;
 
         pthread_mutex_unlock(rb->lock);
 
         return ret;
 }
 
-int shm_ap_rbuff_peek_b(struct shm_ap_rbuff * rb,
-                        const struct timespec * timeout)
+static int shm_ap_rbuff_peek_b_all(struct shm_ap_rbuff * rb,
+                                   const struct timespec * timeout)
 {
         struct timespec abstime;
         int ret = 0;
@@ -397,7 +397,7 @@ int shm_ap_rbuff_peek_b(struct shm_ap_rbuff * rb,
         }
 
         if (ret != ETIMEDOUT)
-                ret = (rb->shm_base + *rb->ptr_tail)->port_id;
+                ret = tail_el_ptr(rb)->port_id;
         else
                 ret = -ETIMEDOUT;
 
@@ -406,6 +406,82 @@ int shm_ap_rbuff_peek_b(struct shm_ap_rbuff * rb,
         return ret;
 }
 
+int shm_ap_rbuff_peek_b(struct shm_ap_rbuff *   rb,
+                        bool *                  set,
+                        const struct timespec * timeout)
+{
+        struct timespec abstime;
+        int ret;
+
+        if (set == NULL)
+                return shm_ap_rbuff_peek_b_all(rb, timeout);
+
+#ifdef __APPLE__
+        pthread_mutex_lock(rb->lock);
+#else
+        if (pthread_mutex_lock(rb->lock) == EOWNERDEAD) {
+                LOG_DBG("Recovering dead mutex.");
+                pthread_mutex_consistent(rb->lock);
+        }
+#endif
+        if (timeout != NULL) {
+                clock_gettime(PTHREAD_COND_CLOCK, &abstime);
+                ts_add(&abstime, timeout, &abstime);
+        }
+
+        pthread_cleanup_push((void(*)(void *))pthread_mutex_unlock,
+                             (void *) rb->lock);
+
+        while ((shm_rbuff_empty(rb) || !set[tail_el_ptr(rb)->port_id])
+               && (ret != ETIMEDOUT)) {
+                while (shm_rbuff_empty(rb)) {
+                        if (timeout != NULL)
+                                ret = pthread_cond_timedwait(rb->add,
+                                                             rb->lock,
+                                                             &abstime);
+                        else
+                                ret = pthread_cond_wait(rb->add, rb->lock);
+
+#ifndef __APPLE__
+                        if (ret == EOWNERDEAD) {
+                                LOG_DBG("Recovering dead mutex.");
+                                pthread_mutex_consistent(rb->lock);
+                        }
+#endif
+                        if (ret == ETIMEDOUT)
+                                break;
+                }
+
+                while (!set[tail_el_ptr(rb)->port_id]) {
+                        if (timeout != NULL)
+                                ret = pthread_cond_timedwait(rb->del,
+                                                             rb->lock,
+                                                             &abstime);
+                        else
+                                ret = pthread_cond_wait(rb->del, rb->lock);
+
+#ifndef __APPLE__
+                        if (ret == EOWNERDEAD) {
+                                LOG_DBG("Recovering dead mutex.");
+                                pthread_mutex_consistent(rb->lock);
+                        }
+#endif
+                        if (ret == ETIMEDOUT)
+                                break;
+                }
+        }
+
+        if (ret != ETIMEDOUT)
+                ret = tail_el_ptr(rb)->port_id;
+        else
+                ret = -ETIMEDOUT;
+
+        pthread_cleanup_pop(true);
+
+        return ret;
+}
+
+
 struct rb_entry * shm_ap_rbuff_read(struct shm_ap_rbuff * rb)
 {
         struct rb_entry * e = NULL;
@@ -471,8 +547,8 @@ ssize_t shm_ap_rbuff_read_port(struct shm_ap_rbuff * rb, int port_id)
         return idx;
 }
 
-ssize_t shm_ap_rbuff_read_port_b(struct shm_ap_rbuff * rb,
-                                 int port_id,
+ssize_t shm_ap_rbuff_read_port_b(struct shm_ap_rbuff *   rb,
+                                 int                     port_id,
                                  const struct timespec * timeout)
 {
         struct timespec abstime;