irmd: flow allocation and fast path

This commit has a first implementation of flow allocation (the "slow
path") and read/write (the "fast path") for ouroboros. It provides
basic but unstable communications over the shared memory.

It required a lot of changes all over the stack, and fixes a number of
previously undetected issues.

This PR still need heavy revision regarding data model, locking and
cleanup.

lib/dev: modifications to the API. It now uses an ap_init() call to
set the AP name and sets the Instance ID to the pid of the process. It
also binds the AP to the shared memory and creates tables for mappings
in the fast path. A call to ap_fini() releases the resources.

lib/shm_ap_rbuff: added ring buffer for data exchange between
processes in the fast path. It passes an index in the shm_du_map.

lib/shm_du_map: rewrote API to work with calls from dev.c. Garbage
collector added. Tests updated to new API.

ipcpd/ipcp-data: removed everything related to flows, as these are
universal for all ap's and kept in ap_data (dev.c), or similar structs
for shim ipcps.

shim-udp: added flow allocator and read/write functions and shm
elements.

irmd: revised data model and structures necessary for flow allocation.

tools: echo updated to new dev.h API.

messaging system was updated to comply with new flow allocation
messages. All exchanges use pid and port_id to bootstrap the fast
path.

1 files changed, 12 insertions, 7 deletions

diff --git a/include/ouroboros/dev.h b/include/ouroboros/dev.h
index 414273ef..e857e211 100644
--- a/include/ouroboros/dev.h
+++ b/include/ouroboros/dev.h
@@ -24,29 +24,34 @@
 #define OUROBOROS_DEV_H
 
 #include <ouroboros/common.h>
+#include <ouroboros/flow.h>
 
 #define UNKNOWN_AP "__UNKNOWN_AP__"
 #define UNKNOWN_AE "__UNKNOWN_AE__"
 
+/* These calls should be removed once we write the ouroboros OS. */
+int     ap_init(char * ap_name);
+void    ap_fini();
+
 /* Returns file descriptor */
-int     ap_reg(char * ap_name, char ** difs, size_t difs_size);
-int     ap_unreg(char * ap_name, char ** difs, size_t difs_size);
+int     ap_reg(char ** difs, size_t difs_size);
+int     ap_unreg(char ** difs, size_t difs_size);
 
 /* Returns file descriptor (> 0) and client name(s) */
-int     flow_accept(int fd, char * ap_name, char * ae_name);
+int     flow_accept(int fd, char ** ap_name, char ** ae_name);
 int     flow_alloc_resp(int fd, int result);
 
 /* Returns file descriptor */
-int     flow_alloc(char * dst_ap_name, char * src_ap_name,
-                   char * src_ae_name, struct qos_spec * qos,
-                   int oflags);
+int     flow_alloc(char * dst_name,
+                   char * src_ae_name,
+                   struct qos_spec * qos);
 
 /* If flow is accepted returns a value > 0 */
 int     flow_alloc_res(int fd);
 int     flow_dealloc(int fd);
 
 /* Wraps around fnctl */
-int     flow_cntl(int fd, int oflags);
+int     flow_cntl(int fd, int cmd, int oflags);
 ssize_t flow_write(int fd, void * buf, size_t count);
 ssize_t flow_read(int fd, void * buf, size_t count);