lib: Add call to reserve blocks in rdrbuff

This adds a call ipcp_sdb_reserve to reserve memory in the rdrbuff
without directly writing to a flow. The ipcp_flow_del function was
renamed to ipcp_sdb_release. The functions operating on sdbs are moved
to their own header.

3 files changed, 59 insertions, 20 deletions

diff --git a/include/ouroboros/ipcp-dev.h b/include/ouroboros/ipcp-dev.h
index 571689ca..cdf9f5c1 100644
--- a/include/ouroboros/ipcp-dev.h
+++ b/include/ouroboros/ipcp-dev.h
@@ -45,9 +45,12 @@ int  ipcp_flow_write(int                  fd,
 
 void ipcp_flow_fini(int fd);
 
-void ipcp_flow_del(struct shm_du_buff * sdb);
-
 int  ipcp_flow_get_qoscube(int         fd,
                            qoscube_t * cube);
 
+int  ipcp_sdb_reserve(struct shm_du_buff ** sdb,
+                      size_t                len);
+
+void ipcp_sdb_release(struct shm_du_buff * sdb);
+
 #endif /* OUROBOROS_IPCP_DEV_H */
diff --git a/include/ouroboros/shm_du_buff.h b/include/ouroboros/shm_du_buff.h
new file mode 100644
index 00000000..9f796be1
--- /dev/null
+++ b/include/ouroboros/shm_du_buff.h
@@ -0,0 +1,53 @@
+/*
+ * Ouroboros - Copyright (C) 2016 - 2017
+ *
+ * Data Buffer element in Random Deletion Ring Buffer
+ *
+ *    Dimitri Staessens <dimitri.staessens@ugent.be>
+ *    Sander Vrijders   <sander.vrijders@ugent.be>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * version 2.1 as published by the Free Software Foundation.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#ifndef OUROBOROS_SHM_DU_BUFF_H
+#define OUROBOROS_SHM_DU_BUFF_H
+
+#include <sys/types.h>
+#include <stdint.h>
+
+struct shm_du_buff;
+
+size_t    shm_du_buff_get_idx(struct shm_du_buff * sdb);
+
+uint8_t * shm_du_buff_head(struct shm_du_buff * sdb);
+
+uint8_t * shm_du_buff_tail(struct shm_du_buff * sdb);
+
+uint8_t * shm_du_buff_head_alloc(struct shm_du_buff * sdb,
+                                 size_t               size);
+
+uint8_t * shm_du_buff_tail_alloc(struct shm_du_buff * sdb,
+                                 size_t               size);
+
+void      shm_du_buff_head_release(struct shm_du_buff * sdb,
+                                   size_t               size);
+
+void      shm_du_buff_tail_release(struct shm_du_buff * sdb,
+                                   size_t               size);
+
+void      shm_du_buff_truncate(struct shm_du_buff * sdb,
+                               size_t               len);
+
+#endif /* OUROBOROS_SHM_DU_BUFF_H */
diff --git a/include/ouroboros/shm_rdrbuff.h b/include/ouroboros/shm_rdrbuff.h
index 92173388..13b99eef 100644
--- a/include/ouroboros/shm_rdrbuff.h
+++ b/include/ouroboros/shm_rdrbuff.h
@@ -24,17 +24,15 @@
 #ifndef OUROBOROS_SHM_RDRBUFF_H
 #define OUROBOROS_SHM_RDRBUFF_H
 
+#include <ouroboros/shm_du_buff.h>
 #include <ouroboros/shared.h>
 
 #include <stdint.h>
 #include <pthread.h>
 #include <sys/types.h>
 
-struct shm_du_buff;
 struct shm_rdrbuff;
 
-size_t               shm_du_buff_get_idx(struct shm_du_buff * sdb);
-
 struct shm_rdrbuff * shm_rdrbuff_create(void);
 
 struct shm_rdrbuff * shm_rdrbuff_open(void);
@@ -68,19 +66,4 @@ struct shm_du_buff * shm_rdrbuff_get(struct shm_rdrbuff * rdrb,
 int                  shm_rdrbuff_remove(struct shm_rdrbuff  * rdrb,
                                         size_t                idx);
 
-uint8_t *            shm_du_buff_head(struct shm_du_buff * sdb);
-
-uint8_t *            shm_du_buff_tail(struct shm_du_buff * sdb);
-
-uint8_t *            shm_du_buff_head_alloc(struct shm_du_buff * sdb,
-                                            size_t               size);
-
-uint8_t *            shm_du_buff_tail_alloc(struct shm_du_buff * sdb,
-                                            size_t               size);
-
-void                 shm_du_buff_head_release(struct shm_du_buff * sdb,
-                                              size_t               size);
-
-void                 shm_du_buff_tail_release(struct shm_du_buff * sdb,
-                                              size_t               size);
 #endif /* OUROBOROS_SHM_RDRBUFF_H */