ELAPI: Adding concept of targets

The targets are the destinations which
caller wants to send the events to.
The sinks are now on the second level
under targets and constitute a so called
fail over chain for a target.
Such approach eliminates the need for complex
routing function.
The dispatcher keeps the list of targets in a collection.
The element in the collection is the target context.
Also gispatcher keeps the list of the sinks
in a separate collection.
Each target context has a list of the sinks
associated with this target. But those are just
pointers (at least for now) to the sinks
form the list kept by dispatcher.

I had to add some internal debug callbacks
to be able to see that all the internals of
the dispatcher are actually in order.
See the conttent of config file for more comments.
Also see information posted on SSSD wiki.
https://fedorahosted.org/sssd/wiki/WikiPage/ELAPIInterface

1 files changed, 95 insertions, 15 deletions

diff --git a/common/elapi/elapi_priv.h b/common/elapi/elapi_priv.h
index c536f4ecf..0fa01b406 100644
--- a/common/elapi/elapi_priv.h
+++ b/common/elapi/elapi_priv.h
@@ -20,6 +20,8 @@
 #ifndef ELAPI_PRIV_H
 #define ELAPI_PRIV_H
 
+#include <stdint.h>
+
 #include "collection.h"
 #include "elapi_async.h"
 /* Classes of the collections used by ELAPI internally */
@@ -27,22 +29,37 @@
 #define COL_CLASS_ELAPI_EVENT       COL_CLASS_ELAPI_BASE + 0
 #define COL_CLASS_ELAPI_TEMPLATE    COL_CLASS_ELAPI_BASE + 1
 #define COL_CLASS_ELAPI_SINK        COL_CLASS_ELAPI_BASE + 2
+#define COL_CLASS_ELAPI_TARGET      COL_CLASS_ELAPI_BASE + 3
+#define COL_CLASS_ELAPI_SINK_REF    COL_CLASS_ELAPI_BASE + 4
 
 /* Names for the collections */
 #define E_TEMPLATE_NAME "template"
 #define E_EVENT_NAME "event"
 
-
+/* Constants used in INI file and in
+ * the internal collection objects.
+ */
 #define ELAPI_DISPATCHER    "dispatcher"
 #define ELAPI_SINKS         "sinks"
+#define ELAPI_TARGETS       "targets"
+#define ELAPI_SINK_REFS     "srefs"
+#define ELAPI_TARGET_VALUE  "value"
+#define ELAPI_SINK_PROVIDER "provider"
+
+#define ELAPI_TARGET_ALL    0xFFFF  /* 65k targets should be enough */
 
 struct elapi_dispatcher {
-    char **sinks;
-    int need_to_free;
+    /* Application name */
     char *appname;
-    /*event_router_fn router; - FIXME - not defined yet */
+    /* List of target names and chars */
+    char **targets;
+    /* Collection of targets */
+    struct collection_item *target_list;
+    /* Counter of the targets */
+    int target_counter;
+    /* Collection of sinks */
     struct collection_item *sink_list;
-    int sink_counter;
+    /* Configuration */
     struct collection_item *ini_config;
     /* Default event template */
     struct collection_item *default_template;
@@ -51,16 +68,47 @@ struct elapi_dispatcher {
     elapi_rem_fd add_fd_rem_fn;
     elapi_add_timer add_timer_fn;
     void *callers_data;
-    int async_mode;
+    uint32_t async_mode;
 };
 
-/* Structure to pass data from logging function to sinks */
-struct elapi_sink_context {
+/* Structure to pass data from logging function to targets */
+struct elapi_target_pass_in_data {
     struct collection_item *event;
     struct elapi_dispatcher *handle;
-    char *format;
-    char *previous;
-    int previous_status;
+    uint32_t target_mask;
+};
+
+/* This is a structure that holds the information
+ *  about the target.
+ */
+struct elapi_target_context {
+    /* Value associted with the
+     * target in the config file.
+     */
+    uint32_t target_value;
+    /* Collection of pointers to sink objects */
+    struct collection_item *sink_ref_list;
+    /* FIXME - other things that belong here are:
+     * state of the chain
+     * reference to the current sink
+     * reference to the preferred sink
+     * etc.
+     */
+};
+
+/* The structure that describes the sink in the dispatcher */
+struct elapi_sink_context {
+    /* Inpit queue of a sink */
+    struct collection_item *in_queue;
+    /* Pending list */
+    struct collection_item *pending;
+    /* FIXME: add:
+     * sink's error status
+     * sink's common config data (common between all sinks)
+     * sink personal specific config data (config data specific to this sink)
+     */
+    /* Is this a sink or async sink */
+    uint32_t async_mode;
 };
 
 /* The structure to hold a command and a result of the command execution */
@@ -102,13 +150,45 @@ int elapi_internal_sink_cleanup_handler(const char *sink,
 /* Create list of the sinks */
 int elapi_internal_construct_sink_list(struct elapi_dispatcher *handle);
 
-/* Function to add a sink to the collection */
-int elapi_internal_add_sink_to_collection(struct collection_item *sink_list,
-                                          char *sink,
-                                          char *appname);
+/* Function to add a sink based on configuration  */
+int elapi_internal_add_sink(struct collection_item **sink_ref,
+                            char *sink,
+                            struct elapi_dispatcher *handle);
+
+/* Create target object */
+int elapi_internal_create_target(struct elapi_target_context **context,
+                                 char *target,
+                                 struct elapi_dispatcher *handle);
+
+/* Destroy target object */
+void elapi_internal_destroy_target(struct elapi_target_context *context);
+
+/* Internal target cleanup function */
+int elapi_internal_target_cleanup_handler(const char *sink,
+                                          int sink_len,
+                                          int type,
+                                          void *data,
+                                          int length,
+                                          void *passed_data,
+                                          int *stop);
+
+/* Handler for logging through the targets */
+int elapi_internal_target_handler(const char *target,
+                                  int target_len,
+                                  int type,
+                                  void *data,
+                                  int length,
+                                  void *passed_data,
+                                  int *stop);
+
+/* Create list of targets for a dispatcher */
+int elapi_internal_construct_target_list(struct elapi_dispatcher *handle);
 
 /* Send ELAPI config errors into a file */
 void elapi_internal_dump_errors_to_file(struct collection_item *error_list);
 
+/* Print dispatcher internals for testing and debugin purposes */
+void elapi_internal_print_dispatcher(struct elapi_dispatcher *handle);
+
 
 #endif