First commit of basic collection API.

1 files changed, 2481 insertions, 0 deletions

diff --git a/common/collection/collection.c b/common/collection/collection.c
new file mode 100644
index 000000000..e393ae3d1
--- /dev/null
+++ b/common/collection/collection.c
@@ -0,0 +1,2481 @@
+/*
+    COLLECTION LIBRARY
+
+    Implemenation of the collection library interface.
+
+    Copyright (C) Dmitri Pal <dpal@redhat.com> 2009
+
+    Collection Library is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    Collection 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 Collection Library.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#define _GNU_SOURCE
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <ctype.h>
+#include <time.h>
+#include "trace.h"
+
+/* The collection should use the teal structures */
+#include "collection_priv.h"
+#include "collection.h"
+
+
+/* Internal constants defined to denote actions that can be performed by find handler */
+#define COLLECTION_ACTION_FIND       1
+#define COLLECTION_ACTION_DEL        2
+#define COLLECTION_ACTION_UPDATE     3
+#define COLLECTION_ACTION_GET        4
+
+
+/* Special internal error code to indicate that collection search was interrupted */
+#define EINTR_INTERNAL 10000
+
+
+/* Potential subjest for management with libtools */
+#define DATE_FORMAT "%c"
+
+#define TIME_ARRAY_SIZE 100
+
+
+/* Struct used for passing parameter for update operation */
+struct update_property {
+        int type;
+        void *data;
+        int length;
+        int found;
+};
+
+/* Dummy structure */
+struct collection_item dummy = { NULL, "", 0, COL_TYPE_END, 0, NULL };
+
+/******************** FUNCTION DECLARATIONS ****************************/
+
+/* Have to declare those due to function cross referencing */
+static int find_item_and_do(struct collection_item *ci,
+                            char *property_to_find,
+                            int type,
+                            int mode_flags,
+                            item_fn item_handler,
+                            void *custom_data,
+                            int action);
+
+/* Traverse callback for find & delete function */
+static int act_traverse_handler(struct collection_item *head,
+                                struct collection_item *previous,
+                                struct collection_item *current,
+                                void *passed_traverse_data,
+                                item_fn user_item_handler,
+                                void *custom_data,
+                                int *stop);
+
+/* Traverse callback signature */
+typedef int (*internal_item_fn)(struct collection_item *head,
+                                struct collection_item *previous,
+                                struct collection_item *current,
+                                void *traverse_data,
+                                item_fn user_item_handler,
+                                void *custom_data,
+                                int *stop);
+
+/******************** SUPPLIMENTARY FUNCTIONS ****************************/
+
+
+/* BASIC OPERATIONS */
+/* Function that checks if property can be added */
+static int validate_property(char *property)
+{
+    TRACE_FLOW_STRING("validate_property","Entry point.");
+    /* Only alpha numeric characters are allowed in names of the properties */
+    int invalid = 0;
+    char *check;
+
+    check = property;
+    while(*check != '\0') {
+        if((!isalnum((int)(*check))) && (!ispunct((int)(*check)))) {
+            invalid = 1;
+            break;
+        }
+        check++;
+    }
+    TRACE_FLOW_NUMBER("validate_property. Returning ",invalid);
+    return invalid;
+}
+
+
+
+/* Function that cleans the item */
+static void delete_item(struct collection_item *item)
+{
+    TRACE_FLOW_STRING("delete_item","Entry point.");
+
+    if(item == (struct collection_item *)NULL) return;
+
+    if(item->property != NULL) free(item->property);
+    if(item->data != NULL) free(item->data);
+
+    free(item);
+
+    TRACE_FLOW_STRING("delete_item","Exit.");
+}
+
+/* A generic function to allocate a property item */
+static int allocate_item(struct collection_item **ci,char *property,void *item_data,int length, int type)
+{
+    struct collection_item *item = NULL;
+    int error = 0;
+    errno = 0;
+
+    TRACE_FLOW_STRING("allocate_item","Entry point.");
+    TRACE_INFO_NUMBER("Will be using type:",type);
+
+    /* Check the length */
+    if(length >= COL_MAX_DATA) {
+        TRACE_ERROR_STRING("allocate_item","Data to long.");
+        return EMSGSIZE;
+    }
+
+    if(validate_property(property)) {
+        TRACE_ERROR_STRING("Invalid chracters in the property name",property);
+        return EINVAL;
+    }
+
+    /* Allocate memory for the structure */
+    item = (struct collection_item *)(malloc(sizeof(struct collection_item)));
+    if(item == (struct collection_item *)(NULL))  {
+        error = errno;
+        TRACE_ERROR_STRING("allocate_item","Malloc failed.");
+        return error;
+    }
+
+    /* After we initialize "next" we can use delete_item() in case of error */
+    item->next = (struct collection_item *)(NULL);
+
+    /* Copy property */
+    item->property = strdup(property);
+    if(item->property == NULL) {
+        error = errno;
+        TRACE_ERROR_STRING("allocate_item","Failed to dup property.");
+        delete_item(item);
+        return error;
+    }
+
+    item->property_len = strlen(item->property);
+
+    /* Deal with data */
+    item->data = malloc(length);
+    if(item->data == NULL) {
+        TRACE_ERROR_STRING("allocate_item","Failed to dup data.");
+        delete_item(item);
+        return errno;
+    }
+    memcpy(item->data,item_data,length);
+
+    /* Deal with other properties of the item */
+    TRACE_INFO_NUMBER("About to set type to:",type);
+    item->type = type;
+    item->length = length;
+
+    /* Make sure that data is NULL terminated in case of string */
+    if(type == COL_TYPE_STRING) *(((char *)(item->data))+length-1) = '\0';
+
+    *ci = item;
+
+    TRACE_INFO_STRING("Item property",item->property);
+    TRACE_INFO_NUMBER("Item property type",item->type);
+    TRACE_INFO_NUMBER("Item data length",item->length);
+    TRACE_FLOW_STRING("allocate_item","Success exit.");
+    return 0;
+}
+
+/* Add item to the end of collection */
+/* Can add itself to itself - nice...*/
+static int add_item_to_collection(struct collection_item *collection,struct collection_item *item)
+{
+    struct collection_header *header;
+
+    TRACE_FLOW_STRING("add_item_to_collection","Entry point.");
+
+    if(collection == (struct collection_item *)(NULL)) {
+        TRACE_INFO_STRING("add_item_to_collection","Collection accepting is NULL");
+        if((item != (struct collection_item *)(NULL)) &&
+           (item->type == COL_TYPE_COLLECTION)) {
+            /* This is a special case of self creation */
+            TRACE_INFO_STRING("add_item_to_collection","Adding header item to new collection.");
+            collection = item;
+        }
+    }
+
+    /* We can add items only to collections */
+    if(collection->type != COL_TYPE_COLLECTION) {
+        TRACE_ERROR_STRING("add_item_to_collection","Attempt to add item to non collection.");
+        TRACE_ERROR_STRING("Collection name:",collection->property);
+        TRACE_ERROR_NUMBER("Collection type:",collection->type);
+        return EINVAL;
+    }
+
+    header = (struct collection_header *)(collection->data);
+
+    /* Link new item to the last item in the list if there any */
+    if(header->last != (struct collection_item *)(NULL)) (header->last)->next = item;
+
+    /* Make sure we save a new last element */
+    header->last = item;
+    header->count++;
+
+    TRACE_INFO_STRING("Collection:",collection->property);
+    TRACE_INFO_STRING("Just added item is:",item->property);
+    TRACE_INFO_NUMBER("Item type.",item->type);
+    TRACE_INFO_NUMBER("Number of items in collection now is.",header->count);
+
+    TRACE_FLOW_STRING("add_item_to_collection","Success exit.");
+    return EOK;
+}
+
+
+/* TRAVERSE HANDLERS */
+
+/* Special handler to just set a flag if the item is found */
+inline static int is_in_item_handler(char *property,
+                                     int property_len,
+                                     int type,
+                                     void *data,
+                                     int length,
+                                     void *found,
+                                     int *dummy)
+{
+    TRACE_FLOW_STRING("is_in_item_handler","Entry.");
+    TRACE_INFO_STRING("Property:",property);
+    TRACE_INFO_NUMBER("Property length:",property_len);
+    TRACE_INFO_NUMBER("Type:",type);
+    TRACE_INFO_NUMBER("Length:",length);
+
+    *((int *)(found)) = COL_MATCH;
+
+    TRACE_FLOW_STRING("is_in_item_handler","Success Exit.");
+
+    return EOK;
+}
+
+/* Special handler to retrieve the sub collection */
+inline static int get_subcollection(char *property,
+                                    int property_len,
+                                    int type,
+                                    void *data,
+                                    int length,
+                                    void *found,
+                                    int *dummy)
+{
+    TRACE_FLOW_STRING("get_subcollection","Entry.");
+    TRACE_INFO_STRING("Property:",property);
+    TRACE_INFO_NUMBER("Property length:",property_len);
+    TRACE_INFO_NUMBER("Type:",type);
+    TRACE_INFO_NUMBER("Length:",length);
+
+    *((struct collection_item **)(found)) = *((struct collection_item **)(data));
+
+    TRACE_FLOW_STRING("get_subcollection","Success Exit.");
+
+    return EOK;
+
+}
+
+
+/* ADD PROPERTY */
+
+/* Add a single property to a collection. Returns a pointer to a newly allocated property */
+static struct collection_item *add_property(struct collection_item *collection,
+                                            char *subcollection,
+                                            char *property,
+                                            void *item_data,
+                                            int length,
+                                            int type,
+                                            int *error)
+{
+    struct collection_item *item;
+    struct collection_item *acceptor = (struct collection_item *)(NULL);
+
+    TRACE_FLOW_STRING("add_property","Entry.");
+    /* Allocate item */
+
+    TRACE_INFO_NUMBER("Property type to add",type);
+    *error = allocate_item(&item,property,item_data,length, type);
+    if(*error) return (struct collection_item *)(NULL);
+
+    TRACE_INFO_STRING("Created item:",item->property);
+    TRACE_INFO_NUMBER("Item has type:",item->type);
+
+    /* Add item to collection */
+    if(subcollection == NULL) acceptor = collection;
+    else {
+        TRACE_INFO_STRING("Subcollection id not null, searching",subcollection);
+        *error = find_item_and_do(collection, subcollection, COL_TYPE_COLLECTIONREF,
+                                  COL_TRAVERSE_DEFAULT,
+                                  get_subcollection,(void *)(&acceptor),COLLECTION_ACTION_FIND);
+        if(*error) {
+            TRACE_ERROR_NUMBER("Search for subcollection returned error:",*error);
+            delete_item(item);
+            return (struct collection_item *)(NULL);
+        }
+
+        if(acceptor == (struct collection_item *)(NULL)) {
+            TRACE_ERROR_STRING("Search for subcollection returned NULL pointer","");
+            delete_item(item);
+            *error=ENOENT;
+            return (struct collection_item *)(NULL);
+        }
+
+    }
+    *error = add_item_to_collection(acceptor,item);
+    if(*error) {
+        TRACE_ERROR_NUMBER("Failed to add item to collection error:",*error);
+        delete_item(item);
+        return (struct collection_item *)(NULL);
+    }
+
+    TRACE_FLOW_STRING("add_property","Success Exit.");
+    return item;
+}
+
+/* CLEANUP */
+
+/* Cleans the collection tree including current item. */
+/* After the execution passed in variable should not be used - memory is gone!!! */
+static void delete_collection(struct collection_item *ci)
+{
+    struct collection_item *other_collection;
+
+    TRACE_FLOW_STRING("delete_collection","Entry.");
+
+    if(ci == (struct collection_item *)(NULL)) {
+        TRACE_FLOW_STRING("delete_collection","Nothing to do Exit.");
+        return;
+    }
+
+    TRACE_INFO_STRING("Real work to do","");
+
+    delete_collection(ci->next);
+
+    /* Handle external or embedded collection */
+    if(ci->type == COL_TYPE_COLLECTIONREF)  {
+        /* Our data is a pointer to a whole external collection so dereference it or delete */
+        other_collection = *((struct collection_item **)(ci->data));
+        destroy_collection(other_collection);
+    }
+
+    /* Delete this item */
+    delete_item(ci);
+    TRACE_FLOW_STRING("delete_collection","Exit.");
+}
+
+
+/* NAME MANAGEMENT - used by search */
+
+/* Internal data structures used for search */
+
+struct path_data {
+    char *name;
+    int length;
+    struct path_data *previous_path;
+};
+
+struct find_name {
+    char *name_to_find;
+    int name_len_to_find;
+    int type_to_match;
+    char *given_name;
+    int given_len;
+    struct path_data *current_path;
+    int action;
+};
+
+/* Create a new name */
+static int create_path_data(struct path_data **name_path,
+                            char *name, int length,
+                            char *property, int property_len)
+{
+    int error = EOK;
+    struct path_data *new_name_path;
+
+    TRACE_FLOW_STRING("create_path_data","Entry.");
+
+    TRACE_INFO_STRING("Constructing path from name:",name);
+    TRACE_INFO_STRING("Constructing path from property:",property);
+
+    /* Allocate structure */
+    errno = 0;
+    new_name_path = (struct path_data *)(malloc(sizeof(struct path_data)));
+    if(new_name_path == (struct path_data *)(NULL)) return errno;
+
+    new_name_path->name=malloc(length+property_len+2);
+    if(new_name_path->name == NULL) {
+        error = errno;
+        TRACE_ERROR_NUMBER("Failed to allocate memory for new path name. Errno",error);
+        free((void *)(new_name_path));
+        return error;
+    }
+
+    /* Construct the new name */
+    new_name_path->length = 0;
+
+    if(length > 0) {
+        memcpy(new_name_path->name,name,length);
+        new_name_path->length = length;
+        *(new_name_path->name+new_name_path->length) = '.';
+        new_name_path->length++;
+        *(new_name_path->name+new_name_path->length) = '\0';
+        TRACE_INFO_STRING("Name so far:",new_name_path->name);
+        TRACE_INFO_NUMBER("Len so far:",new_name_path->length);
+    }
+    memcpy(new_name_path->name+new_name_path->length,property,property_len);
+    new_name_path->length += property_len;
+    *(new_name_path->name + new_name_path->length) = '\0';
+
+    /* Link to the chain */
+    new_name_path->previous_path = *name_path;
+    *name_path = new_name_path;
+
+    TRACE_INFO_STRING("Constructed path",new_name_path->name);
+
+
+    TRACE_FLOW_NUMBER("create_path_data. Returning:",error);
+    return error;
+}
+
+/* Matching item name and type */
+static int match_item(struct collection_item *current,
+                      struct find_name *traverse_data)
+{
+
+    char *find_str;
+    char *start;
+    char *data_str;
+
+    TRACE_FLOW_STRING("match_item","Entry");
+
+    if(traverse_data->type_to_match & current->type) {
+        /* Check if there is any value to match */
+        if((traverse_data->name_to_find == NULL) ||
+           (*(traverse_data->name_to_find) == '\0')) {
+            TRACE_INFO_STRING("match_item","Returning MATCH because there is no search criteria!");
+            return COL_MATCH;
+        }
+
+        /* Start comparing the two strings from the end */
+        find_str = traverse_data->name_to_find + traverse_data->name_len_to_find;
+        start = current->property;
+        data_str = start + current->property_len;
+
+        TRACE_INFO_STRING("Searching for:",traverse_data->name_to_find);
+        TRACE_INFO_STRING("Item name:",current->property);
+        TRACE_INFO_STRING("Current path:",traverse_data->current_path->name);
+        TRACE_INFO_NUMBER("Searching:",toupper(*find_str));
+        TRACE_INFO_NUMBER("Have:",toupper(*data_str));
+
+        /* We start pointing to 0 so the loop will be executed at least once */
+        while(toupper(*data_str) == toupper(*find_str)) {
+
+            TRACE_INFO_STRING("Loop iteration:","");
+
+            if(data_str == start) {
+                if(find_str > traverse_data->name_to_find) {
+                    if(*(find_str-1) == '.') {
+                        /* We matched the property but the search string is longer */
+                        /* so we need to continue matching */
+                        TRACE_INFO_STRING("match_item","Need to continue matching");
+                        start = traverse_data->current_path->name;
+                        data_str = start + traverse_data->current_path->length - 1;
+                        find_str-=2;
+                        continue;
+                    }
+                    else {
+                        TRACE_INFO_STRING("match_item","Returning NO match!");
+                        return COL_NOMATCH;
+                    }
+                }
+                else {
+                    TRACE_INFO_STRING("match_item","Returning MATCH!");
+                    return COL_MATCH;
+                }
+            }
+            else if((find_str == traverse_data->name_to_find) &&
+                    (*(data_str-1) == '.')) return COL_MATCH;
+
+            data_str--;
+            find_str--;
+             TRACE_INFO_NUMBER("Searching:",toupper(*find_str));
+            TRACE_INFO_NUMBER("Have:",toupper(*data_str));
+
+        }
+    }
+
+    TRACE_FLOW_STRING("match_item","Returning NO match!");
+    return COL_NOMATCH;
+
+}
+
+/* Function to delete the data that contains search path */
+static void delete_path_data(struct path_data *path)
+{
+    TRACE_FLOW_STRING("delete_path_data","Entry.");
+
+    if(path!= (struct path_data *)(NULL)) {
+        TRACE_INFO_STRING("delete_path_data","Item to delete exits.");
+        if(path->previous_path != (struct path_data *)(NULL)) {
+            TRACE_INFO_STRING("delete_path_data","But previous item to delete exits to. Nesting.");
+            delete_path_data(path->previous_path);
+        }
+        if(path->name != NULL) {
+            TRACE_INFO_STRING("delete_path_data Deleting path:",path->name);
+            free(path->name);
+        }
+        TRACE_INFO_STRING("delete_path_data","Deleting path element");
+        free((void *)(path));
+    }
+    TRACE_FLOW_STRING("delete_path_data","Exit");
+}
+
+
+/* MAIN TRAVERSAL FUNCTION */
+
+/* Internal function to walk collection */
+/* For each item walked it will call traverse handler.
+   Traverse handler accepts: current item,
+   user provided item handler and user provided custom data. */
+/* See below defferent traverse handlers for different cases */
+static int walk_items(struct collection_item *ci,
+                      int mode_flags,
+                      internal_item_fn traverse_handler,
+                      void *traverse_data,
+                      item_fn user_item_handler,
+                      void *custom_data) {
+
+    struct collection_item *current;
+    struct collection_item *parent;
+    struct collection_item *sub;
+    int stop = 0;
+    int error = EOK;
+
+    TRACE_FLOW_STRING("walk_items","Entry.");
+    TRACE_INFO_NUMBER("Mode flags:",mode_flags);
+
+    current = ci;
+
+    while(current != (struct collection_item *)(NULL)) {
+
+        TRACE_INFO_STRING("Processing item:",current->property);
+        TRACE_INFO_NUMBER("Item type:",current->type);
+
+        if(current->type == COL_TYPE_COLLECTIONREF) {
+
+            TRACE_INFO_STRING("Subcollection:",current->property);
+
+            if((mode_flags & COL_TRAVERSE_IGNORE) == 0) {
+
+                TRACE_INFO_STRING("Subcollection is not ignored.","");
+
+                /* We are not ignoring sub collections */
+                error = traverse_handler(ci,parent,current,traverse_data,user_item_handler,custom_data,&stop);
+                if(stop != 0) {
+                    TRACE_INFO_STRING("Traverse handler returned STOP.","");
+                    error = EINTR_INTERNAL;
+                }
+                /* Check what error we got */
+                if(error == EINTR_INTERNAL) {
+                    TRACE_FLOW_NUMBER("Internal error - means we are stopping.",error);
+                    return error;
+                }
+                else if(error) {
+                    TRACE_ERROR_NUMBER("Traverse handler returned error.",error);
+                    return error;
+                }
+
+                if((mode_flags & COL_TRAVERSE_ONELEVEL) == 0) {
+                    TRACE_INFO_STRING("Before diving into sub collection","");
+                    sub = *((struct collection_item **)(current->data));
+                    TRACE_INFO_STRING("Sub collection name",sub->property);
+                    TRACE_INFO_NUMBER("Header type",sub->type);
+                    /* We need to go into sub collections */
+                    error = walk_items(sub, mode_flags,traverse_handler,traverse_data,
+                                       user_item_handler, custom_data);
+                    TRACE_INFO_STRING("Returned from sub collection processing","");
+                    TRACE_INFO_STRING("Done processing item:",current->property);
+                    TRACE_INFO_NUMBER("Done processing item type:",current->type);
+
+                }
+            }
+        }
+        else
+            /* Call handler then move on */
+            error = traverse_handler(ci,parent,current,traverse_data,user_item_handler,custom_data,&stop);
+
+        /* If we are stopped - return EINTR_INTERNAL */
+        if(stop != 0) {
+            TRACE_INFO_STRING("Traverse handler returned STOP.","");
+            error = EINTR_INTERNAL;
+        }
+        /* Check what error we got */
+        if(error == EINTR_INTERNAL) {
+            TRACE_FLOW_NUMBER("Internal error - means we are stopping.",error);
+            return error;
+        }
+        else if(error) {
+            TRACE_ERROR_NUMBER("Traverse handler returned error.",error);
+            return error;
+        }
+
+        parent = current;
+        current = current->next;
+
+    }
+
+    TRACE_INFO_STRING("Out of loop","");
+
+    if((mode_flags & COL_TRAVERSE_END) != 0) {
+        TRACE_INFO_STRING("About to do the special end collection invocation of handler","");
+        error = traverse_handler(ci,parent,current,traverse_data,user_item_handler,custom_data,&stop);
+    }
+
+    TRACE_FLOW_NUMBER("walk_items. Returns: ",error);
+    return error;
+}
+
+
+/* ACTION */
+
+/* Find an item by property name and perform an action on it. */
+/* No pattern matching supported in the first implementation. */
+/* To refer to child properties use dotted notatation like this: */
+/* parent.child.subchild.subsubchild etc.  */
+static int find_item_and_do(struct collection_item *ci,
+                            char *property_to_find,
+                            int type,
+                            int mode_flags,
+                            item_fn item_handler,
+                            void *custom_data,
+                            int action)
+{
+
+    int error = EOK;
+    struct find_name *traverse_data = NULL;
+
+    TRACE_FLOW_STRING("find_item_and_do","Entry.");
+
+    /* Item handler is always required */
+    if((item_handler == (item_fn)(NULL)) && (action ==COLLECTION_ACTION_FIND)) {
+        TRACE_ERROR_NUMBER("No item handler - returning error!",EINVAL);
+        return EINVAL;
+    }
+
+    /* Make sure that there is anything to search */
+    type &= COL_TYPE_ANY;
+    if((ci == (struct collection_item *)(NULL)) ||
+       ((property_to_find == NULL) && (type == 0)) ||
+       ((*property_to_find == '\0') && (type == 0))) {
+        TRACE_ERROR_NUMBER("No item search criteria specified - returning error!",ENOKEY);
+        return ENOKEY;
+    }
+    /* Prepare data for traversal */
+    errno = 0;
+    traverse_data= (struct find_name *)(malloc(sizeof(struct find_name)));
+    if(traverse_data == (struct find_name *)(NULL)) {
+        error = errno;
+        TRACE_ERROR_NUMBER("Failed to allocate traverse data memory - returning error!",errno);
+        return error;
+    }
+
+    TRACE_INFO_STRING("find_item_and_do","Filling in traverse data.");
+
+    traverse_data->name_to_find = property_to_find;
+    traverse_data->name_len_to_find = strlen(property_to_find);
+    traverse_data->type_to_match = type;
+    traverse_data->given_name = NULL;
+    traverse_data->given_len = 0;
+    traverse_data->current_path = (struct path_data *)(NULL);
+    traverse_data->action = action;
+
+    mode_flags |= COL_TRAVERSE_END;
+
+    TRACE_INFO_STRING("find_item_and_do","About to walk the tree.");
+    TRACE_INFO_NUMBER("Traverse flags",mode_flags);
+
+    error = walk_items(ci, mode_flags, act_traverse_handler,
+                       (void *)traverse_data, item_handler, custom_data);
+
+    if(traverse_data->current_path != (struct path_data *)(NULL)) {
+        TRACE_INFO_STRING("find_item_and_do","Path was not cleared - deleting");
+        delete_path_data(traverse_data->current_path);
+    }
+
+    free((void *)(traverse_data));
+
+    if((error) && (error != EINTR_INTERNAL)) {
+        TRACE_ERROR_NUMBER("Walk items returned error. Returning: ",error);
+        return error;
+    }
+    else {
+        TRACE_FLOW_STRING("Walk items returned SUCCESS.","");
+        return EOK;
+    }
+}
+
+/* Function to replace data in the item */
+static int update_current_item(struct collection_item *current,
+                               struct update_property *update_data)
+{
+    int error = EOK;
+    TRACE_FLOW_STRING("update_current_item","Entry");
+
+    /* If type is different or same but it is string or binary we need to replace the storage */
+    if((current->type != update_data->type) ||
+       ((current->type == update_data->type) &&
+       ((current->type == COL_TYPE_STRING) || (current->type == COL_TYPE_BINARY)))) {
+        TRACE_INFO_STRING("Replacing item data buffer","");
+        free(current->data);
+        current->data = malloc(update_data->length);
+        if(current->data == NULL) {
+            TRACE_ERROR_STRING("Failed to allocate memory","");
+            current->length = 0;
+            return ENOMEM;
+        }
+        current->length = update_data->length;
+    }
+
+    TRACE_INFO_STRING("Overwriting item data","");
+    memcpy(current->data,update_data->data,current->length);
+    current->type = update_data->type;
+
+    if(current->type == COL_TYPE_STRING) *(((char *)(current->data))+current->length-1) = '\0';
+
+    TRACE_FLOW_STRING("update_current_item","Exit");
+    return EOK;
+}
+
+/* TRAVERSE CALLBACKS */
+
+/* Traverse handler for simple traverse function */
+/* Handler must be able to deal with NULL current item */
+inline static int simple_traverse_handler(struct collection_item *head,
+                                          struct collection_item *previous,
+                                          struct collection_item *current,
+                                          void *traverse_data,
+                                          item_fn user_item_handler,
+                                          void *custom_data,
+                                          int *stop)
+{
+    int error = EOK;
+
+    TRACE_FLOW_STRING("simple_traverse_handler","Entry.");
+
+    if(current == (struct collection_item *)(NULL)) current = &dummy;
+
+    error = user_item_handler(current->property,
+                              current->property_len,
+                              current->type,
+                              current->data,
+                              current->length,
+                              custom_data,
+                              stop);
+
+    TRACE_FLOW_NUMBER("simple_traverse_handler. Returning:",error);
+    return error;
+}
+
+
+/* Traverse callback for find & delete function */
+static int act_traverse_handler(struct collection_item *head,
+                                struct collection_item *previous,
+                                struct collection_item *current,
+                                void *passed_traverse_data,
+                                item_fn user_item_handler,
+                                void *custom_data,
+                                int *stop)
+{
+    int error = EOK;
+    struct find_name *traverse_data = NULL;
+    char *name;
+    int length;
+    struct path_data *temp;
+    struct collection_header *header;
+    struct collection_item *other;
+    char *property;
+    int property_len;
+    struct update_property *update_data;
+
+    TRACE_FLOW_STRING("act_traverse_handler","Entry.");
+
+    traverse_data = (struct find_name *)(passed_traverse_data);
+
+    /* We can be called when current points to NULL */
+    if(current==(struct collection_item *)(NULL)) {
+        TRACE_INFO_STRING("act_traverse_handler","Special call at the end of the collection.");
+        temp = traverse_data->current_path;
+        traverse_data->current_path = temp->previous_path;
+        temp->previous_path = (struct path_data *)(NULL);
+        delete_path_data(temp);
+        traverse_data->given_name = NULL;
+        traverse_data->given_len = 0;
+        TRACE_FLOW_NUMBER("Handling end of collection - removed path. Returning:", error);
+        return error;
+    }
+
+    /* Create new path at the beginning of a new sub collection */
+    if(current->type == COL_TYPE_COLLECTION) {
+
+        TRACE_INFO_STRING("act_traverse_handler","Processing collection handle.");
+
+        /* Create new path */
+        if(traverse_data->current_path != (struct path_data *)(NULL)) {
+            TRACE_INFO_STRING("Already have part of the path","");
+            name = (traverse_data->current_path)->name;
+            length = (traverse_data->current_path)->length;
+            TRACE_INFO_STRING("Path:",name);
+            TRACE_INFO_NUMBER("Path len:",length);
+        }
+        else {
+            name = NULL;
+            length = 0;
+        }
+
+        if(traverse_data->given_name != NULL) {
+            property = traverse_data->given_name;
+            property_len = traverse_data->given_len;
+        }
+        else {
+            property = current->property;
+            property_len = current->property_len;
+        }
+
+        TRACE_INFO_STRING("act_traverse_handler","About to create path data.");
+
+        error = create_path_data(&(traverse_data->current_path),
+                                 name, length, property,property_len);
+
+        TRACE_INFO_NUMBER("create_path_data returned:", error);
+        return error;
+    }
+
+    /* Handle the collection pointers */
+    if(current->type == COL_TYPE_COLLECTIONREF) {
+        traverse_data->given_name = current->property;
+        traverse_data->given_len = current->property_len;
+        TRACE_INFO_STRING("Saved given name:",traverse_data->given_name);
+    }
+
+    TRACE_INFO_STRING("Processing item with property:",current->property);
+
+    /* Do here what we do with items */
+    if(match_item(current,traverse_data)) {
+        TRACE_INFO_STRING("Matched item:",current->property);
+        switch(traverse_data->action) {
+            case COLLECTION_ACTION_FIND:
+                TRACE_INFO_STRING("It is a find action - calling handler.","");
+                if(user_item_handler != (item_fn)(NULL)) {
+                    /* Call user handler */
+                    error = user_item_handler(current->property,
+                                              current->property_len,
+                                              current->type,
+                                              current->data,
+                                              current->length,
+                                              custom_data,
+                                              stop);
+
+                    TRACE_INFO_NUMBER("Handler returned:",error);
+                    TRACE_INFO_NUMBER("Handler set STOP to:",*stop);
+
+                }
+                break;
+            case COLLECTION_ACTION_GET:
+                TRACE_INFO_STRING("It is a get action.","");
+                if(custom_data != NULL) *((struct collection_item **)(custom_data)) = current;
+                break;
+            case COLLECTION_ACTION_DEL:
+                TRACE_INFO_STRING("It is a delete action.","");
+                /* Make sure we tell the caller we found a match */
+                if(custom_data != NULL) *(int *)(custom_data) = COL_MATCH;
+                /* Dereference external collections */
+                if(current->type == COL_TYPE_COLLECTIONREF) {
+                    TRACE_INFO_STRING("Dereferencing a referenced collection.","");
+                    other = *((struct collection_item **)(current->data));
+                    header = (struct collection_header *)(other->data);
+                    destroy_collection(other);
+                }
+
+                /* Adjust header of the collection */
+                header = (struct collection_header *)(head->data);
+                (header->count)--;
+                if(current->next == (struct collection_item *)(NULL)) header->last = previous;
+
+                /* Unlink and delete iteam */
+                /* Previous can't be NULL here becuase we never delete header elements */
+                previous->next = current->next;
+                delete_item(current);
+                TRACE_INFO_STRING("Did the delete of the item.","");
+                break;
+            case COLLECTION_ACTION_UPDATE:
+                TRACE_INFO_STRING("It is an update action.","");
+                if((current->type == COL_TYPE_COLLECTION) ||
+                   (current->type == COL_TYPE_COLLECTIONREF)) {
+                    TRACE_ERROR_STRING("Can't update collections it is an error for now","");
+                    return EINVAL;
+                }
+
+                /* Make sure we tell the caller we found a match */
+                if(custom_data != NULL) {
+                    update_data = (struct update_property *) custom_data;
+                    update_data-> found = COL_MATCH;
+                    error = update_current_item(current, update_data);
+                }
+                else {
+                    TRACE_ERROR_STRING("Error - update data is required","");
+                    return EINVAL;
+                }
+
+                TRACE_INFO_STRING("Did the delete of the item.","");
+                break;
+            default:
+                break;
+        }
+        /* Force interrupt if we found */
+        *stop = 1;
+    }
+
+    TRACE_FLOW_NUMBER("act_traverse_handler returning",error);
+    return error;
+}
+
+
+/* Traverse handler for copy function */
+static int copy_traverse_handler(struct collection_item *head,
+                                 struct collection_item *previous,
+                                 struct collection_item *current,
+                                 void *passed_traverse_data,
+                                 item_fn user_item_handler,
+                                 void *custom_data,
+                                 int *stop)
+{
+    int error = EOK;
+    struct collection_item *parent;
+    struct collection_item *item;
+    struct collection_item *new_collection = (struct collection_item *)(NULL);
+
+    TRACE_FLOW_STRING("copy_traverse_handler","Entry.");
+
+    parent = (struct collection_item *)(passed_traverse_data);
+
+    /* Skip current element but rather work with next if it is not NULL */
+    item = current->next;
+    if(item == (struct collection_item *)(NULL)) return error;
+
+
+    /* Check if this is a special case of sub collection */
+    if(item->type == COL_TYPE_COLLECTIONREF) {
+        TRACE_INFO_STRING("Found a subcollection we need to copy. Name:",item->property);
+
+        error = copy_collection(&new_collection,
+                                *((struct collection_item **)(item->data)),
+                                item->property);
+        if(error) {
+            TRACE_ERROR_NUMBER("Copy subcollection returned error:",error);
+            return error;
+        }
+
+        /* Add new item to a collection - all references are now sub collections */
+        (void)add_property(parent,NULL,item->property,(void *)(&new_collection),
+                           sizeof(struct collection_item **),
+                           COL_TYPE_COLLECTIONREF, &error);
+        if(error) {
+            TRACE_ERROR_NUMBER("Add property returned error:",error);
+            return error;
+        }
+    }
+    else {
+        (void)add_property(parent,NULL,item->property,item->data,
+                           item->length,item->type,&error);
+        if(error) {
+            TRACE_ERROR_NUMBER("Add property returned error:",error);
+            return error;
+        }
+    }
+
+    TRACE_FLOW_NUMBER("copy_traverse_handler returning",error);
+    return error;
+}
+
+
+
+/********************* MAIN INTERFACE FUNCTIONS ***********************************/
+
+
+/* CREATE */
+
+/* Function that creates an named collection of a given class*/
+int create_collection(struct collection_item **ci,char *name, unsigned class)
+{
+    struct collection_item *handle = (struct collection_item *)(NULL);
+    struct collection_header header;
+    int error=EOK;
+
+    TRACE_FLOW_STRING("create_collection","Entry.");
+
+    /* Prepare header */
+    header.last = (struct collection_item *)(NULL);
+    header.reference_count = 1;
+    header.count = 0;
+    header.class = class;
+
+    /* Create a collection type property */
+    handle = add_property((struct collection_item *)(NULL),NULL,name,&header,sizeof(header), COL_TYPE_COLLECTION, &error);
+    if(error) return error;
+
+    *ci = handle;
+
+    TRACE_FLOW_STRING("create_collection","Success Exit.");
+    return 0;
+}
+
+
+/* DESTROY */
+
+/* Function that destroys a collection */
+void destroy_collection(struct collection_item *ci)
+{
+    struct collection_header *header;
+
+    TRACE_FLOW_STRING("destroy_collection","Entry.");
+
+    /* Do not try to delete NULL */
+    if(ci == (struct collection_item *)(NULL)) return;
+
+    /* You can delete only whole collection not a part of it */
+    if(ci->type != COL_TYPE_COLLECTION) {
+        TRACE_ERROR_STRING("Attempt to delete a non collection - BAD!","");
+        TRACE_ERROR_NUMBER("Actual type is:",ci->type);
+        return;
+    }
+
+    /* Collection can be referenced by other collection */
+    header = (struct collection_header *)(ci->data);
+    if(header->reference_count>1) {
+        TRACE_INFO_STRING("Dereferencing a referenced collection.","");
+        (header->reference_count)--;
+        TRACE_INFO_NUMBER("Number after dereferencing.",header->reference_count);
+    }
+    else delete_collection(ci);
+
+    TRACE_FLOW_STRING("destroy_collection","Exit.");
+}
+
+
+/* PROPERTIES */
+
+/* Add a string property.
+   If length equals 0, the length is determined based on the string.
+   Lenght INCLUDES the terminating 0 */
+inline int add_str_property(struct collection_item *ci,char *subcollection, char *property,char *string,int length)
+{
+    int error = EOK;
+
+    TRACE_FLOW_STRING("add_str_property","Entry.");
+
+    if(length == 0) length = strlen(string) + 1;
+    (void)(add_property(ci,subcollection,property,(void *)(string),length, COL_TYPE_STRING, &error));
+
+    TRACE_FLOW_NUMBER("add_str_property returning",error);
+    return error;
+}
+
+/* Add a binary property. */
+inline int add_binary_property(struct collection_item *ci,char *subcollection, char *property,void *binary_data,int length)
+{
+    int error = EOK;
+
+    TRACE_FLOW_STRING("add_binary_property","Entry.");
+
+    (void)(add_property(ci,subcollection,property,binary_data,length, COL_TYPE_BINARY, &error));
+
+    TRACE_FLOW_NUMBER("add_binary_property returning",error);
+    return error;
+}
+
+/* Add an int property. */
+inline int add_int_property(struct collection_item *ci,char *subcollection, char *property,int number)
+{
+    int error = EOK;
+
+    TRACE_FLOW_STRING("add_int_property","Entry.");
+
+    (void)(add_property(ci,subcollection,property,(void *)(&number),sizeof(int), COL_TYPE_INTEGER, &error));
+
+    TRACE_FLOW_NUMBER("add_int_property returning",error);
+    return error;
+}
+
+/* Add an unsigned int property. */
+inline int add_unsigned_property(struct collection_item *ci,char *subcollection, char *property,unsigned int number)
+{
+    int error = EOK;
+
+    TRACE_FLOW_STRING("add_unsigned_property","Entry.");
+
+    (void)(add_property(ci,subcollection,property,(void *)(&number),sizeof(int), COL_TYPE_UNSIGNED, &error));
+
+    TRACE_FLOW_NUMBER("add_unsigned_property returning",error);
+    return error;
+}
+
+/* Add an long property. */
+inline int add_long_property(struct collection_item *ci,char *subcollection, char *property,long number)
+{
+    int error = EOK;
+
+    TRACE_FLOW_STRING("add_long_property","Entry.");
+
+    (void)(add_property(ci,subcollection,property,(void *)(&number),sizeof(long), COL_TYPE_LONG, &error));
+
+    TRACE_FLOW_NUMBER("add_long_property returning",error);
+    return error;
+}
+
+/* Add an unsigned long property. */
+inline int add_ulong_property(struct collection_item *ci,char *subcollection, char *property,unsigned long number)
+{
+    int error = EOK;
+
+    TRACE_FLOW_STRING("add_ulong_property","Entry.");
+
+    (void)(add_property(ci,subcollection,property,(void *)(&number),sizeof(long), COL_TYPE_ULONG, &error));
+
+    TRACE_FLOW_NUMBER("add_ulong_property returning",error);
+    return error;
+}
+
+/* Add a double property. */
+inline int add_double_property(struct collection_item *ci,char *subcollection, char *property,double number)
+{
+    int error = EOK;
+
+    TRACE_FLOW_STRING("add_double_property","Entry.");
+
+    (void)(add_property(ci,subcollection,property,(void *)(&number),sizeof(double), COL_TYPE_DOUBLE, &error));
+
+    TRACE_FLOW_NUMBER("add_double_property returning",error);
+    return error;
+}
+
+/* Add a bool property. */
+inline int add_bool_property(struct collection_item *ci,char *subcollection, char *property,unsigned char logical)
+{
+    int error = EOK;
+
+    TRACE_FLOW_STRING("add_bool_property","Entry.");
+
+    (void)(add_property(ci,subcollection,property,(void *)(&logical),sizeof(unsigned char), COL_TYPE_BOOL, &error));
+
+    TRACE_FLOW_NUMBER("add_bool_property returning",error);
+    return error;
+}
+
+/* A function to add a property */
+inline int add_any_property(struct collection_item *ci,
+                            char *subcollection,
+                            char *property,
+                            int type,
+                            void *data,
+                            int length)
+{
+    int error = EOK;
+
+    TRACE_FLOW_STRING("add_any_property","Entry.");
+
+    (void)(add_property(ci,subcollection,property,data,length, type, &error));
+
+    TRACE_FLOW_NUMBER("add_any_property returning",error);
+    return error;
+}
+
+/* Add a string property.
+   If length equals 0, the length is determined based on the string.
+   Lenght INCLUDES the terminating 0 */
+inline int add_str_property_with_ref(struct collection_item *ci,char *subcollection,
+                                     char *property,char *string,int length,
+                                     struct collection_item **ref_ret)
+{
+    int error = EOK;
+    struct collection_item *item;
+
+    TRACE_FLOW_STRING("add_str_property_with_ref","Entry.");
+
+    if(length == 0) length = strlen(string) + 1;
+    item = add_property(ci,subcollection,property,(void *)(string),length, COL_TYPE_STRING, &error);
+
+    if(ref_ret != (struct collection_item **)(NULL)) *ref_ret = item;
+
+    TRACE_FLOW_NUMBER("add_str_property_with_ref returning",error);
+    return error;
+}
+
+/* Add a binary property. */
+inline int add_binary_property_with_ref(struct collection_item *ci,char *subcollection,
+                                        char *property,void *binary_data,int length,
+                                        struct collection_item **ref_ret)
+{
+    int error = EOK;
+    struct collection_item *item;
+
+    TRACE_FLOW_STRING("add_binary_property_with_ref","Entry.");
+
+    item = add_property(ci,subcollection,property,binary_data,length, COL_TYPE_BINARY, &error);
+
+    if(ref_ret != (struct collection_item **)(NULL)) *ref_ret = item;
+
+    TRACE_FLOW_NUMBER("add_binary_property_with_ref returning",error);
+    return error;
+}
+
+/* Add an int property. */
+inline int add_int_property_with_ref(struct collection_item *ci,char *subcollection,
+                                     char *property,int number,
+                                     struct collection_item **ref_ret)
+{
+    int error = EOK;
+    struct collection_item *item;
+
+    TRACE_FLOW_STRING("add_int_property_with_ref","Entry.");
+
+    item = add_property(ci,subcollection,property,(void *)(&number),sizeof(int), COL_TYPE_INTEGER, &error);
+
+    if(ref_ret != (struct collection_item **)(NULL)) *ref_ret = item;
+
+    TRACE_FLOW_NUMBER("add_int_property_with_ref returning",error);
+    return error;
+}
+
+/* Add an unsigned int property. */
+inline int add_unsigned_property_with_ref(struct collection_item *ci,char *subcollection,
+                                          char *property,unsigned int number,
+                                          struct collection_item **ref_ret)
+{
+    int error = EOK;
+    struct collection_item *item;
+
+    TRACE_FLOW_STRING("add_unsigned_property_with_ref","Entry.");
+
+    item = add_property(ci,subcollection,property,(void *)(&number),sizeof(int), COL_TYPE_UNSIGNED, &error);
+
+    if(ref_ret != (struct collection_item **)(NULL)) *ref_ret = item;
+
+    TRACE_FLOW_NUMBER("add_unsigned_property_with_ref returning",error);
+    return error;
+}
+
+/* Add an long property. */
+inline int add_long_property_with_ref(struct collection_item *ci,char *subcollection,
+                                      char *property,long number,
+                                      struct collection_item **ref_ret)
+{
+    int error = EOK;
+    struct collection_item *item;
+
+    TRACE_FLOW_STRING("add_long_property_with_ref","Entry.");
+
+    item = add_property(ci,subcollection,property,(void *)(&number),sizeof(long), COL_TYPE_LONG, &error);
+
+    if(ref_ret != (struct collection_item **)(NULL)) *ref_ret = item;
+
+    TRACE_FLOW_NUMBER("add_long_property_with_ref returning",error);
+    return error;
+}
+
+/* Add an unsigned long property. */
+inline int add_ulong_property_with_ref(struct collection_item *ci,char *subcollection,
+                                       char *property,unsigned long number,
+                                       struct collection_item **ref_ret)
+{
+    int error = EOK;
+    struct collection_item *item;
+
+    TRACE_FLOW_STRING("add_ulong_property_with_ref","Entry.");
+
+    item = add_property(ci,subcollection,property,(void *)(&number),sizeof(long), COL_TYPE_ULONG, &error);
+
+    if(ref_ret != (struct collection_item **)(NULL)) *ref_ret = item;
+
+    TRACE_FLOW_NUMBER("add_ulong_property_with_ref returning",error);
+    return error;
+}
+
+/* Add a double property. */
+inline int add_double_property_with_ref(struct collection_item *ci,char *subcollection,
+                                        char *property,double number,
+                                        struct collection_item **ref_ret)
+{
+    int error = EOK;
+    struct collection_item *item;
+
+    TRACE_FLOW_STRING("add_double_property_with_ref","Entry.");
+
+    item = add_property(ci,subcollection,property,(void *)(&number),sizeof(double), COL_TYPE_DOUBLE, &error);
+
+    if(ref_ret != (struct collection_item **)(NULL)) *ref_ret = item;
+
+    TRACE_FLOW_NUMBER("add_double_property_with_ref returning",error);
+    return error;
+}
+
+/* Add a bool property. */
+inline int add_bool_property_with_ref(struct collection_item *ci,char *subcollection,
+                                      char *property,unsigned char logical,
+                                      struct collection_item **ref_ret)
+{
+    int error = EOK;
+    struct collection_item *item;
+
+    TRACE_FLOW_STRING("add_bool_property_with_ref","Entry.");
+
+    item = add_property(ci,subcollection,property,(void *)(&logical),sizeof(unsigned char), COL_TYPE_BOOL, &error);
+
+    if(ref_ret != (struct collection_item **)(NULL)) *ref_ret = item;
+
+    TRACE_FLOW_NUMBER("add_bool_property_with_ref returning",error);
+    return error;
+}
+
+/* A function to add a property */
+inline int add_any_property_with_ref(struct collection_item *ci,
+                                     char *subcollection,
+                                     char *property,
+                                     int type,
+                                     void *data,
+                                     int length,
+                                     struct collection_item **ref_ret)
+{
+    int error = EOK;
+    struct collection_item *item;
+
+    TRACE_FLOW_STRING("add_any_property_with_ref","Entry.");
+
+    item = add_property(ci,subcollection,property,data,length, type, &error);
+
+    if(ref_ret != (struct collection_item **)(NULL)) *ref_ret = item;
+
+    TRACE_FLOW_NUMBER("add_any_property_with_ref returning",error);
+    return error;
+}
+
+
+
+/* COPY */
+
+/* Create a deep copy of the current collection. */
+/* Referenced collections of the donor are copied as sub collections. */
+int copy_collection(struct collection_item **collection_copy,
+                    struct collection_item *collection_to_copy,
+                    char *name_to_use) {
+
+    int error = EOK;
+    struct collection_item *new_collection = (struct collection_item *)(NULL);
+    char *name;
+    struct collection_header *header;
+
+    TRACE_FLOW_STRING("copy_collection","Entry.");
+
+    /* Determine what name to use */
+    if(name_to_use != NULL) name = name_to_use;
+    else name = collection_to_copy->property;
+
+    header = (struct collection_header *)(collection_to_copy->data);
+
+    /* Create a new collection */
+    error = create_collection(&new_collection,name,header->class);
+    if(error) {
+        TRACE_ERROR_NUMBER("Create_cllection failed returning",error);
+        return error;
+    }
+
+    error = walk_items(collection_to_copy, COL_TRAVERSE_ONELEVEL, copy_traverse_handler,
+                       new_collection, NULL, NULL);
+
+    if(!error) *collection_copy = new_collection;
+    else destroy_collection(new_collection);
+
+    TRACE_FLOW_NUMBER("copy_collection returning",error);
+    return error;
+
+}
+
+/* EXTRACTION */
+
+/* Extract collection */
+int get_collection_reference(struct collection_item *ci,          /* High level collection */
+                             struct collection_item **acceptor,   /* The pointer that will accept extracted handle */
+                             char *collection_to_find)            /* Name to of the collection */
+{
+    struct collection_header *header;
+    struct collection_item *subcollection = (struct collection_item *)(NULL);
+    int error = EOK;
+
+    TRACE_FLOW_STRING("get_collection_reference","Entry.");
+
+    if((ci == (struct collection_item *)(NULL)) ||
+       (ci->type != COL_TYPE_COLLECTION) ||
+       (acceptor == (struct collection_item **)(NULL)) ||
+       (collection_to_find == NULL)) {
+        TRACE_ERROR_NUMBER("Invalid parameter - returning error",EINVAL);
+        return EINVAL;
+    }
+
+    /* Find a sub collection */
+    TRACE_INFO_STRING("We are given subcollection name - search it:",collection_to_find);
+    error = find_item_and_do(ci,collection_to_find,COL_TYPE_COLLECTIONREF,
+                             COL_TRAVERSE_DEFAULT,
+                             get_subcollection,(void *)(&subcollection),COLLECTION_ACTION_FIND);
+    if(error) {
+        TRACE_ERROR_NUMBER("Search failed returning error",error);
+        return error;
+    }
+
+    if(subcollection == (struct collection_item *)(NULL)) {
+        TRACE_ERROR_STRING("Search for subcollection returned NULL pointer","");
+        return ENOENT;
+    }
+
+    header = (struct collection_header *)(subcollection->data);
+    TRACE_INFO_NUMBER("Count:",header->count);
+    TRACE_INFO_NUMBER("Ref count:",header->reference_count);
+    (header->reference_count)++;
+    TRACE_INFO_NUMBER("Ref count after increment:",header->reference_count);
+    *acceptor = subcollection;
+
+    TRACE_FLOW_STRING("get_collection_reference","Success Exit.");
+    return EOK;
+}
+
+/* Get collection - if current item is a reference get a real collection from it. */
+int get_reference_from_item(struct collection_item *ci,
+                            struct collection_item **acceptor)
+{
+    struct collection_header *header;
+    struct collection_item *subcollection = (struct collection_item *)(NULL);
+    int error = EOK;
+
+    TRACE_FLOW_STRING("get_reference_from_item","Entry.");
+
+    if((ci == (struct collection_item *)(NULL)) ||
+       (ci->type != COL_TYPE_COLLECTIONREF) ||
+       (acceptor == (struct collection_item **)(NULL))) {
+        TRACE_ERROR_NUMBER("Invalid parameter - returning error",EINVAL);
+        return EINVAL;
+    }
+
+    subcollection = *((struct collection_item **)(ci->data));
+
+    header = (struct collection_header *)(subcollection->data);
+    TRACE_INFO_NUMBER("Count:",header->count);
+    TRACE_INFO_NUMBER("Ref count:",header->reference_count);
+    (header->reference_count)++;
+    TRACE_INFO_NUMBER("Ref count after increment:",header->reference_count);
+    *acceptor = subcollection;
+
+    TRACE_FLOW_STRING("get_reference_from_item","Success Exit.");
+    return EOK;
+}
+
+/* ADDITION */
+
+/* Add collection to collection */
+int add_collection_to_collection(
+   struct collection_item *ci,                /* Collection handle to with we add another collection */
+   char *sub_collection_name,                 /* Name of the sub collection to which
+                                                 collection needs to be added as a property.
+                                                 If NULL high level collection is assumed. */
+   char *as_property,                         /* Name of the collection property.
+                                                 If NULL, same property as the name of
+                                                 the collection being added will be used. */
+   struct collection_item *collection_to_add, /* Collection to add */
+   int mode)                                  /* How this collection needs to be added */
+{
+    struct collection_item *acceptor = (struct collection_item *)(NULL);
+    char *name_to_use;
+    struct collection_header *header;
+    struct collection_item *collection_copy;
+    int error = EOK;
+
+    TRACE_FLOW_STRING("add_collection_to_collection","Entry.");
+
+    if((ci == (struct collection_item *)(NULL)) ||
+       (ci->type != COL_TYPE_COLLECTION) ||
+       (collection_to_add == (struct collection_item *)(NULL)) ||
+       (collection_to_add->type != COL_TYPE_COLLECTION)) {
+        /* Need to debug here */
+        TRACE_ERROR_NUMBER("Missing parameter - returning error",EINVAL);
+        return EINVAL;
+    }
+
+    if(sub_collection_name != NULL) {
+        /* Find a sub collection */
+        TRACE_INFO_STRING("We are given subcollection name - search it:",sub_collection_name);
+        error = find_item_and_do(ci,sub_collection_name,COL_TYPE_COLLECTIONREF,
+                                 COL_TRAVERSE_DEFAULT,
+                                 get_subcollection,(void *)(&acceptor),COLLECTION_ACTION_FIND);
+        if(error) {
+            TRACE_ERROR_NUMBER("Search failed returning error",error);
+            return error;
+        }
+
+        if(acceptor == (struct collection_item *)(NULL)) {
+            TRACE_ERROR_STRING("Search for subcollection returned NULL pointer","");
+            return ENOENT;
+        }
+
+    }
+    else acceptor = ci;
+
+    if(as_property != NULL)
+        name_to_use = as_property;
+    else
+        name_to_use = collection_to_add->property;
+
+
+    TRACE_INFO_STRING("Going to use name:",name_to_use);
+
+
+    switch(mode) {
+        case COL_ADD_MODE_REFERENCE:
+            TRACE_INFO_STRING("We are adding a reference.","");
+            TRACE_INFO_NUMBER("Type of the header element:",collection_to_add->type);
+            TRACE_INFO_STRING("Header name we are adding.",collection_to_add->property);
+            /* Create a pointer to external collection */
+            /* For future thread safety: Transaction start -> */
+            (void)(add_property(acceptor,NULL,name_to_use,(void *)(&collection_to_add),
+                                sizeof(struct collection_item **),
+                                COL_TYPE_COLLECTIONREF, &error));
+
+            TRACE_INFO_NUMBER("Type of the header element after add_property:",collection_to_add->type);
+            TRACE_INFO_STRING("Header name we just added.",collection_to_add->property);
+            if(error) {
+                TRACE_ERROR_NUMBER("Adding property failed with error:",error);
+                return error;
+            }
+            header = (struct collection_header *)(collection_to_add->data);
+            TRACE_INFO_NUMBER("Count:",header->count);
+            TRACE_INFO_NUMBER("Ref count:",header->reference_count);
+            (header->reference_count)++;
+            TRACE_INFO_NUMBER("Ref count after increment:",header->reference_count);
+            /* -> Transaction end */
+            break;
+        case COL_ADD_MODE_EMBED:
+            TRACE_INFO_STRING("We are embedding the collection.","");
+            /* First check if the passed in collection is referenced more than once */
+            TRACE_INFO_NUMBER("Type of the header element we are adding:",collection_to_add->type);
+            TRACE_INFO_STRING("Header name we are adding.",collection_to_add->property);
+            TRACE_INFO_NUMBER("Type of the header element we are adding to:",acceptor->type);
+            TRACE_INFO_STRING("Header name we are adding to.",acceptor->property);
+
+            (void)(add_property(acceptor,NULL,name_to_use,(void *)(&collection_to_add),
+                                sizeof(struct collection_item **),
+                                COL_TYPE_COLLECTIONREF, &error));
+
+            TRACE_INFO_NUMBER("Adding property returned:",error);
+            break;
+
+        case COL_ADD_MODE_CLONE:
+            TRACE_INFO_STRING("We are cloning the collection.","");
+            TRACE_INFO_STRING("Name we will use.",name_to_use);
+
+            /* For future thread safety: Transaction start -> */
+            error = copy_collection(&collection_copy, collection_to_add, name_to_use);
+            if(error) return error;
+
+            TRACE_INFO_STRING("We have a collection copy.", collection_copy->property);
+            TRACE_INFO_NUMBER("Collection type.", collection_copy->type);
+            TRACE_INFO_STRING("Acceptor collection.", acceptor->property);
+            TRACE_INFO_NUMBER("Acceptor collection type.", acceptor->type);
+
+            (void)(add_property(acceptor,NULL,name_to_use,(void *)(&collection_copy),
+                                sizeof(struct collection_item **),
+                                COL_TYPE_COLLECTIONREF, &error));
+
+            /* -> Transaction end */
+            TRACE_INFO_NUMBER("Adding property returned:",error);
+            break;
+
+        default: error = EINVAL;
+    }
+
+    TRACE_FLOW_NUMBER("add_collection_to_collection returning:",error);
+    return error;
+}
+
+/* TRAVERSING */
+
+/* Function to traverse the entire collection including optionally sub collections */
+inline int traverse_collection(struct collection_item *ci,
+                               int mode_flags,
+                               item_fn item_handler,
+                               void *custom_data)
+{
+
+    int error = EOK;
+    TRACE_FLOW_STRING("traverse_collection","Entry.");
+
+    error = walk_items(ci, mode_flags, simple_traverse_handler,
+                       NULL, item_handler, custom_data);
+
+    if((error != 0) && (error != EINTR_INTERNAL)) {
+        TRACE_ERROR_NUMBER("Error walking tree",error);
+        return error;
+    }
+
+    TRACE_FLOW_STRING("traverse_collection","Success exit.");
+    return EOK;
+}
+
+/* CHECK */
+
+/* Convenience function to check if specific property is in the collection */
+inline int is_item_in_collection(struct collection_item *ci,
+                                 char *property_to_find,
+                                 int type,
+                                 int mode_flags,
+                                 int *found)
+{
+    int error;
+
+    TRACE_FLOW_STRING("is_item_in_collection","Entry.");
+
+    *found = COL_NOMATCH;
+    error = find_item_and_do(ci,property_to_find,type,mode_flags,
+                             is_in_item_handler,(void *)found,COLLECTION_ACTION_FIND);
+
+    TRACE_FLOW_NUMBER("is_item_in_collection returning",error);
+    return error;
+}
+
+/* SEARCH */
+/* Search function. Looks up an item in the collection based on the property.
+   Essentually it is a traverse function with spacial traversing logic.
+ */
+inline int get_item_and_do(struct collection_item *ci,       /* Collection to find things in */
+                           char *property_to_find,           /* Name to match */
+                           int type,                         /* Type filter */
+                           int mode_flags,                   /* How to traverse the collection */
+                           item_fn item_handler,             /* Function to call when the item is found */
+                           void *custom_data)                /* Custom data passed around */
+{
+    int error = EOK;
+
+    TRACE_FLOW_STRING("get_item_and_do","Entry.");
+
+    error = find_item_and_do(ci,property_to_find,type,mode_flags,item_handler,custom_data,COLLECTION_ACTION_FIND);
+
+    TRACE_FLOW_NUMBER("get_item_and_do returning",error);
+    return error;
+}
+
+
+/* Get raw item */
+inline int get_item(struct collection_item *ci,       /* Collection to find things in */
+                    char *property_to_find,           /* Name to match */
+                    int type,                         /* Type filter */
+                    int mode_flags,                   /* How to traverse the collection */
+                    struct collection_item **item)    /* Found item */
+{
+
+    int error = EOK;
+
+    TRACE_FLOW_STRING("get_item","Entry.");
+
+    error = find_item_and_do(ci,property_to_find,type,mode_flags,NULL,(void *)(item),COLLECTION_ACTION_GET);
+
+    TRACE_FLOW_NUMBER("get_item returning",error);
+    return error;
+}
+
+/* DELETE */
+/* Delete property from the collection */
+inline int delete_property(struct collection_item *ci,    /* Collection to find things in */
+                           char *property_to_find,        /* Name to match */
+                           int type,                      /* Type filter */
+                           int mode_flags)                /* How to traverse the collection */
+{
+    int error = EOK;
+    int found;
+
+    TRACE_FLOW_STRING("delete_property","Entry.");
+    found = COL_NOMATCH;
+
+    error = find_item_and_do(ci,property_to_find,type,mode_flags,NULL,(void *)(&found),COLLECTION_ACTION_DEL);
+
+    if((error == EOK) && (found == COL_NOMATCH)) error = ENOENT;
+    TRACE_FLOW_NUMBER("delete_property returning",error);
+    return error;
+}
+
+/* UPDATE */
+/* Update property in the collection */
+int update_property(struct collection_item *ci,    /* Collection to find things in */
+                    char *property_to_find,        /* Name to match */
+                    int type,                      /* Type of the passed in data */
+                    void *new_data,                /* Pointer to the new data */
+                    int length,                    /* Length of the data. For strings should include trailing 0 */
+                    int mode_flags)                /* How to traverse the collection  */
+
+{
+    int error = EOK;
+    struct update_property update_data;
+
+    TRACE_FLOW_STRING("update_property","Entry.");
+    update_data.type = type;
+    update_data.data = new_data;
+    update_data.length = length;
+    update_data.found = COL_NOMATCH;
+
+    error = find_item_and_do(ci,property_to_find,type,mode_flags,NULL,(void *)(&update_data),COLLECTION_ACTION_UPDATE);
+
+    if((error == EOK) && (update_data.found == COL_NOMATCH)) error = ENOENT;
+    TRACE_FLOW_NUMBER("update_property returning",error);
+    return error;
+}
+
+/* Update a string property in the collection. Length should include the null terminating 0  */
+inline int update_str_property(struct collection_item *ci,
+                               char *property,
+                               int mode_flags,
+                               char *string,
+                               int length)
+{
+    int error = EOK;
+    TRACE_FLOW_STRING("update_str_property","Entry.");
+
+    if(length == 0) length = strlen(string) + 1;
+    error =  update_property(ci,property, COL_TYPE_STRING, (void *)(string),length,mode_flags);
+
+    TRACE_FLOW_NUMBER("update_str_property Returning",error);
+    return error;
+}
+
+/* Update a binary property in the collection.  */
+inline int update_binary_property(struct collection_item *ci,
+                                  char *property,
+                                  int mode_flags,
+                                  void *binary_data,
+                                  int length)
+{
+    int error = EOK;
+    TRACE_FLOW_STRING("update_binary_property","Entry.");
+
+    error =  update_property(ci,property, COL_TYPE_BINARY, binary_data, length, mode_flags);
+
+    TRACE_FLOW_NUMBER("update_binary_property Returning",error);
+    return error;
+}
+
+/* Update an int property in the collection. */
+inline int update_int_property(struct collection_item *ci,
+                               char *property,
+                               int mode_flags,
+                               int number)
+{
+    int error = EOK;
+    TRACE_FLOW_STRING("update_int_property","Entry.");
+
+    error =  update_property(ci,property, COL_TYPE_INTEGER, (void *)(&number), sizeof(int), mode_flags);
+
+    TRACE_FLOW_NUMBER("update_int_property Returning",error);
+    return error;
+}
+
+/* Update an unsigned int property. */
+inline int update_unsigned_property(struct collection_item *ci,
+                                    char *property,int mode_flags,
+                                    unsigned int number)
+{
+    int error = EOK;
+    TRACE_FLOW_STRING("update_unsigned_property","Entry.");
+
+    error =  update_property(ci,property, COL_TYPE_UNSIGNED, (void *)(&number), sizeof(unsigned int), mode_flags);
+
+    TRACE_FLOW_NUMBER("update_unsigned_property Returning",error);
+    return error;
+}
+/* Update a long property. */
+inline int update_long_property(struct collection_item *ci,
+                                char *property,
+                                int mode_flags,
+                                long number)
+{
+    int error = EOK;
+    TRACE_FLOW_STRING("update_long_property","Entry.");
+
+    error =  update_property(ci,property, COL_TYPE_LONG, (void *)(&number), sizeof(long), mode_flags);
+
+    TRACE_FLOW_NUMBER("update_long_property Returning",error);
+    return error;
+
+}
+
+/* Update an unsigned long property. */
+inline int update_ulong_property(struct collection_item *ci,
+                                 char *property,
+                                 int mode_flags,
+                                 unsigned long number)
+{
+    int error = EOK;
+    TRACE_FLOW_STRING("update_ulong_property","Entry.");
+
+    error =  update_property(ci,property, COL_TYPE_ULONG, (void *)(&number), sizeof(unsigned long), mode_flags);
+
+    TRACE_FLOW_NUMBER("update_ulong_property Returning",error);
+    return error;
+}
+
+/* Update a double property. */
+inline int update_double_property(struct collection_item *ci,
+                                  char *property,
+                                  int mode_flags,
+                                  double number)
+{
+    int error = EOK;
+    TRACE_FLOW_STRING("update_double_property","Entry.");
+
+    error =  update_property(ci,property, COL_TYPE_DOUBLE, (void *)(&number), sizeof(double), mode_flags);
+
+    TRACE_FLOW_NUMBER("update_double_property Returning",error);
+    return error;
+}
+
+/* Update a bool property. */
+inline int update_bool_property(struct collection_item *ci,
+                                char *property,
+                                int mode_flags,
+                                unsigned char logical)
+{
+    int error = EOK;
+    TRACE_FLOW_STRING("update_bool_property","Entry.");
+
+    error =  update_property(ci,property, COL_TYPE_BOOL, (void *)(&logical), sizeof(unsigned char), mode_flags);
+
+    TRACE_FLOW_NUMBER("update_bool_property Returning",error);
+    return error;
+}
+
+/* Function to modify the item */
+int modify_item(struct collection_item *item,
+                char *property,
+                int type,
+                void *data,
+                int length)
+{
+    int error = EOK;
+
+    TRACE_FLOW_STRING("modify_item","Entry");
+
+    if((item == (struct collection_item *)(NULL)) ||
+       (item->type == COL_TYPE_COLLECTION) ||
+       (item->type == COL_TYPE_COLLECTIONREF)) {
+        TRACE_ERROR_NUMBER("Invalid argument or invalid argument type",EINVAL);
+        return EINVAL;
+    }
+
+    if(property != NULL) {
+        free(item->property);
+        item->property=strdup(property);
+        if(item->property == NULL) {
+            TRACE_ERROR_STRING("Failed to allocate memory","");
+            return ENOMEM;
+        }
+    }
+
+    /* If type is different or same but it is string or binary we need to replace the storage */
+    if((item->type != type) ||
+       ((item->type == type) &&
+       ((item->type == COL_TYPE_STRING) || (item->type == COL_TYPE_BINARY)))) {
+        TRACE_INFO_STRING("Replacing item data buffer","");
+        free(item->data);
+        item->data = malloc(length);
+        if(item->data == NULL) {
+            TRACE_ERROR_STRING("Failed to allocate memory","");
+            item->length = 0;
+            return ENOMEM;
+        }
+        item->length = length;
+    }
+
+
+    TRACE_INFO_STRING("Overwriting item data","");
+    memcpy(item->data,data,item->length);
+    item->type = type;
+
+    if(item->type == COL_TYPE_STRING) *(((char *)(item->data))+item->length-1) = '\0';
+
+    TRACE_FLOW_STRING("modify_item","Exit");
+    return EOK;
+}
+
+
+/* Convinience functions that wrap modify_item(). */
+/* Modify item data to be str */
+inline int modify_str_item(struct collection_item *item,
+                           char *property,
+                           char *string,
+                           int length)
+{
+    int len;
+    int error;
+
+    TRACE_FLOW_STRING("modify_str_item","Entry");
+
+    if(length != 0) len = length;
+    else len = strlen(string) + 1;
+
+    error = modify_item(item,property,COL_TYPE_STRING,(void *)string,len);
+
+    TRACE_FLOW_STRING("modify_str_item","Exit");
+    return error;
+}
+
+/* Modify item data to be binary */
+inline int modify_binary_item(struct collection_item *item,
+                              char *property,
+                              void *binary_data,
+                              int length)
+{
+    int error;
+
+    TRACE_FLOW_STRING("modify_binary_item","Entry");
+
+    error = modify_item(item,property,COL_TYPE_BINARY,binary_data,length);
+
+    TRACE_FLOW_STRING("modify_binary_item","Exit");
+    return error;
+}
+
+/* Modify item data to be bool */
+inline int modify_bool_item(struct collection_item *item,
+                            char *property,
+                            unsigned char logical)
+{
+    int error;
+
+    TRACE_FLOW_STRING("modify_bool_item","Entry");
+
+    error = modify_item(item,property,COL_TYPE_BOOL,(void *)(&logical),1);
+
+    TRACE_FLOW_STRING("modify_bool_item","Exit");
+    return error;
+}
+
+/* Modify item data to be int */
+inline int modify_int_item(struct collection_item *item,
+                           char *property,
+                           int number)
+{
+    int error;
+
+    TRACE_FLOW_STRING("modify_int_item","Entry");
+
+    error = modify_item(item,property,COL_TYPE_INTEGER,(void *)(&number),sizeof(int));
+
+    TRACE_FLOW_STRING("modify_int_item","Exit");
+    return error;
+}
+
+/* Modify item data to be long */
+inline int modify_long_item(struct collection_item *item,
+                            char *property,
+                            long number)
+{
+    int error;
+
+    TRACE_FLOW_STRING("modify_long_item","Entry");
+
+    error = modify_item(item,property,COL_TYPE_LONG,(void *)(&number),sizeof(long));
+
+    TRACE_FLOW_STRING("modify_long_item","Exit");
+    return error;
+}
+
+/* Modify item data to be unigned long */
+inline int modify_ulong_item(struct collection_item *item,
+                             char *property,
+                             unsigned long number)
+{
+    int error;
+
+    TRACE_FLOW_STRING("modify_ulong_item","Entry");
+
+    error = modify_item(item,property,COL_TYPE_ULONG,(void *)(&number),sizeof(unsigned long));
+
+    TRACE_FLOW_STRING("modify_ulong_item","Exit");
+    return error;
+}
+
+inline int modify_unsigned_item(struct collection_item *item,
+                                char *property,
+                                unsigned number)
+{
+    int error;
+
+    TRACE_FLOW_STRING("modify_unsigned_item","Entry");
+
+    error = modify_item(item,property,COL_TYPE_UNSIGNED,(void *)(&number),sizeof(unsigned));
+
+    TRACE_FLOW_STRING("modify_unsigned_item","Exit");
+    return error;
+}
+
+inline int modify_double_item(struct collection_item *item,
+                              char *property,
+                              double number)
+{
+    int error;
+
+    TRACE_FLOW_STRING("modify_double_item","Entry");
+
+    error = modify_item(item,property,COL_TYPE_DOUBLE,(void *)(&number),sizeof(double));
+
+    TRACE_FLOW_STRING("modify_double_item","Exit");
+    return error;
+}
+
+
+/* Grow iteration stack */
+static int grow_stack(struct collection_iterator *iterator, unsigned desired)
+{
+    int error;
+    int grow_by = 0;
+    struct collection_item **temp;
+
+    TRACE_FLOW_STRING("grow_stack","Entry.");
+
+    if(desired > iterator->stack_size) {
+        grow_by = (((desired - iterator->stack_size) / STACK_DEPTH_BLOCK) + 1) * STACK_DEPTH_BLOCK;
+        errno = 0;
+        temp = (struct collection_item **)(realloc(iterator->stack,grow_by * sizeof(struct collection_item *)));
+        if(temp == (struct collection_item **)(NULL)) {
+            TRACE_ERROR_NUMBER("Failed to allocate memory",ENOMEM);
+            return ENOMEM;
+        }
+        iterator->stack = temp;
+        iterator->stack_size += grow_by;
+    }
+    TRACE_FLOW_STRING("grow_stack","Exit.");
+    return EOK;
+}
+
+
+
+/* Bind iterator to a collection */
+int bind_iterator(struct collection_iterator **iterator,
+                  struct collection_item *ci,
+                  int mode_flags)
+{
+    int error;
+    struct collection_header *header;
+    struct collection_iterator *iter = (struct collection_iterator *)(NULL);
+
+    TRACE_FLOW_STRING("bind_iterator","Entry.");
+
+    /* Do some argument checking first */
+    if((iterator == (struct collection_iterator **)(NULL)) ||
+       (ci == (struct collection_item *)(NULL))) {
+        TRACE_ERROR_NUMBER("Invalid parameter.",EINVAL);
+        return EINVAL;
+    }
+
+    iter = (struct collection_iterator *)malloc(sizeof(struct collection_iterator));
+    if(iter == (struct collection_iterator *)(NULL)) {
+        TRACE_ERROR_NUMBER("Error allocating memory for the iterator.",ENOMEM);
+        return ENOMEM;
+    }
+
+    /* Allocate memory for the stack */
+    iter->stack = (struct collection_item **)(NULL);
+    iter->stack_size = 0;
+    iter->stack_depth = 0;
+    iter->flags = mode_flags;
+
+    /* Allocate memory for stack */
+    error = grow_stack(iter,1);
+    if(error) {
+        free(iter);
+        TRACE_ERROR_NUMBER("Error growing stack.",error);
+        return error;
+    }
+
+    /* Make sure that we tie iterator to the collection */
+    header = (struct collection_header *)(ci->data);
+    (header->reference_count)++;
+    iter->top = ci;
+    *(iter->stack) = ci;
+    iter->stack_depth++;
+
+    *iterator = iter;
+
+    TRACE_FLOW_STRING("bind_iterator","Exit");
+    return EOK;
+}
+
+/* Stop processing this subcollection and move to the next item in the collection 'level' levels up.*/
+inline int iterate_up(struct collection_iterator *iterator, int level)
+{
+    TRACE_FLOW_STRING("iterate_up","Entry");
+
+    if((iterator == (struct collection_iterator *)(NULL)) ||
+       (level >= iterator->stack_depth)) {
+        TRACE_ERROR_NUMBER("Invalid parameter.",EINVAL);
+        return EINVAL;
+    }
+
+    TRACE_INFO_NUMBER("Going up:",level);
+
+    iterator->stack_depth--;
+
+    TRACE_INFO_NUMBER("Stack depth at the end:",iterator->stack_depth);
+    TRACE_FLOW_STRING("iterate_up","Exit");
+    return EOK;
+}
+/* How deep are we relative to the top level.*/
+inline int get_iterator_depth(struct collection_iterator *iterator, int *depth)
+{
+    TRACE_FLOW_STRING("iterate_up","Entry");
+
+    if((iterator == (struct collection_iterator *)(NULL)) ||
+       (depth == (int *)(NULL))) {
+        TRACE_ERROR_NUMBER("Invalid parameter.",EINVAL);
+        return EINVAL;
+    }
+
+    *depth = iterator->stack_depth -1;
+
+    TRACE_INFO_NUMBER("Stack depth at the end:",iterator->stack_depth);
+    TRACE_FLOW_STRING("iterate_up","Exit");
+    return EOK;
+}
+
+
+/* Unbind the iterator from the collection */
+inline void unbind_iterator(struct collection_iterator *iterator)
+{
+    TRACE_FLOW_STRING("unbind_iterator","Entry.");
+    if(iterator != (struct collection_iterator *)(NULL)) {
+        destroy_collection(iterator->top);
+        if(iterator->stack != (struct collection_item **)(NULL)) free(iterator->stack);
+        free(iterator);
+    }
+    TRACE_FLOW_STRING("unbind_iterator","Exit");
+}
+
+/* Get items from the collection one by one following the tree */
+int iterate_collection(struct collection_iterator *iterator, struct collection_item **item)
+{
+    int error;
+    struct collection_item *current;
+    struct collection_item *other;
+
+    TRACE_FLOW_STRING("iterate_collection","Entry.");
+
+    /* Check if we have storage for item */
+    if(item == (struct collection_item **)(NULL)) {
+        TRACE_ERROR_NUMBER("Invalid parameter.",EINVAL);
+        return EINVAL;
+    }
+
+    while(1) {
+
+        TRACE_INFO_NUMBER("Stack depth:",iterator->stack_depth);
+
+        /* Are we done? */
+        if(iterator->stack_depth == 0) {
+            TRACE_FLOW_STRING("We are done.","");
+            *item = (struct collection_item *)(NULL);
+            return EOK;
+        }
+
+        /* Is current item available */
+        current = *(iterator->stack + iterator->stack_depth - 1);
+
+        /* We are not done so check if we have an item  */
+        if(current != (struct collection_item *)(NULL)) {
+
+            TRACE_INFO_STRING("Current item:",current->property);
+            TRACE_INFO_NUMBER("Current item type:",current->type);
+
+            /* Is this a collection reference */
+            if(current->type == COL_TYPE_COLLECTIONREF) {
+                /* We do follow references? */
+                TRACE_INFO_STRING("Current item:","collection reference");
+                if((iterator->flags & COL_TRAVERSE_IGNORE) == 0) {
+                    /* We should not ignore - then move on */
+                    TRACE_INFO_STRING("Collection references are not ignored","");
+                    error = grow_stack(iterator,iterator->stack_depth + 1);
+                    if(error) {
+                        TRACE_ERROR_NUMBER("Error growing stack.",error);
+                        return error;
+                    }
+                    /* Do we need to go deeper than one level ? */
+                    if((iterator->flags & COL_TRAVERSE_ONELEVEL) == 0) {
+                        TRACE_INFO_STRING("Need to go deeper","");
+                        /* We need to go deeper... */
+                        /* Do we need to show headers but not reference? */
+                        if((iterator->flags & COL_TRAVERSE_ONLYSUB) != 0) {
+                            TRACE_INFO_STRING("Instructed to show header not reference","");
+                            other = *((struct collection_item **)(current->data));
+                            *(iterator->stack + iterator->stack_depth) = other->next;
+                            *item = other;
+                        }
+                        /* Do we need to show both? */
+                        else if((iterator->flags & COL_TRAVERSE_SHOWSUB) != 0) {
+                            TRACE_INFO_STRING("Instructed to show header and reference","");
+                            *(iterator->stack + iterator->stack_depth) = *((struct collection_item **)(current->data));
+                            *item = current;
+                        }
+                        /* We need to show reference only */
+                        else {
+                            TRACE_INFO_STRING("Instructed to show reference only","");
+                            other = *((struct collection_item **)(current->data));
+                            TRACE_INFO_STRING("Sub collection:",other->property);
+                            TRACE_INFO_NUMBER("Sub collection type:",other->type);
+                            *(iterator->stack + iterator->stack_depth) = other->next;
+                            if(other->next != (struct collection_item *)(NULL)) {
+                                TRACE_INFO_STRING("Will show this item next time:",(other->next)->property);
+                                TRACE_INFO_NUMBER("Will show this item next time type:",(other->next)->type);
+                            }
+                            *item = current;
+                        }
+
+                        TRACE_INFO_STRING("We return item:",(*item)->property);
+                        TRACE_INFO_NUMBER("We return item type:",(*item)->type);
+                        TRACE_INFO_STRING("Moving to the next item on the previous item in stack","");
+                        *(iterator->stack + iterator->stack_depth - 1) = current->next;
+                        (iterator->stack_depth)++;
+
+                    }
+                    else {
+                        TRACE_INFO_STRING("Instructed to parse just one level","");
+                        /* On one level - just return current */
+                        *item = current;
+                        TRACE_INFO_STRING("Moving to the next item on one level","");
+                        *(iterator->stack + iterator->stack_depth - 1) = current->next;
+                    }
+                    break;
+                }
+                else {
+                    /* We need to ignore references so move to the next item */
+                    TRACE_INFO_STRING("Stepping over the reference","");
+                    *(iterator->stack + iterator->stack_depth - 1) = current->next;
+                    continue;
+                }
+            }
+            else {
+                /* Got a normal item - return it and move to the next one */
+                TRACE_INFO_STRING("Simple item","");
+                *item = current;
+                *(iterator->stack + iterator->stack_depth - 1) = current->next;
+                break;
+            }
+        }
+        else {
+            /* Item is NULL */
+            TRACE_INFO_STRING("Finished level","moving to upper level");
+            iterator->stack_depth--;
+            TRACE_INFO_NUMBER("Stack depth at the end:",iterator->stack_depth);
+            if((iterator->flags & COL_TRAVERSE_END) != 0) {
+                /* Return dummy entry to indicate the end of the collection */
+                TRACE_INFO_STRING("Finished level","told to return END");
+                *item = &dummy;
+                break;
+            }
+            else continue; /* Move to next level */
+        }
+    }
+
+    TRACE_FLOW_STRING("iterate_collection","Exit");
+    return EOK;
+}
+
+/* Set collection class */
+inline int set_collection_class(struct collection_item *item, unsigned class)
+{
+    struct collection_header *header;
+
+    TRACE_FLOW_STRING("set_collection_class","Entry");
+
+    if(item->type != COL_TYPE_COLLECTION) {
+        TRACE_INFO_NUMBER("Not a collectin object. Type is",item->type);
+        return EINVAL;
+    }
+
+    header = (struct collection_header *)(item->data);
+    header->class = class;
+    TRACE_FLOW_STRING("set_collection_class","Exit");
+    return EOK;
+}
+
+/* Get collection class */
+inline int get_collection_class(struct collection_item *item,
+                                unsigned *class)
+{
+    struct collection_header *header;
+
+    TRACE_FLOW_STRING("get_collection_class","Entry");
+
+    if(item->type != COL_TYPE_COLLECTION) {
+        TRACE_ERROR_NUMBER("Not a collection object. Type is",item->type);
+        return EINVAL;
+    }
+
+    header = (struct collection_header *)(item->data);
+    *class  = header->class;
+    TRACE_FLOW_STRING("get_collection_class","Exit");
+    return EOK;
+}
+
+/* Get collection count */
+inline int get_collection_count(struct collection_item *item,
+                                unsigned *count)
+{
+    struct collection_header *header;
+
+    TRACE_FLOW_STRING("get_collection_count","Entry");
+
+    if(item->type != COL_TYPE_COLLECTION) {
+        TRACE_ERROR_NUMBER("Not a collectin object. Type is",item->type);
+        return EINVAL;
+    }
+
+    header = (struct collection_header *)(item->data);
+    *count  = header->count;
+    TRACE_FLOW_STRING("get_collection_count","Exit");
+    return EOK;
+
+}
+
+/* Convinience function to check if the collection is of the specific class */
+/* In case of internal error assumes that collection is not of the right class */
+inline int is_of_class(struct collection_item *item,unsigned class)
+{
+    int error = EOK;
+    unsigned ret_class = 0;
+
+    TRACE_FLOW_STRING("is_of_class invoked","");
+
+    error = get_collection_class(item,&ret_class);
+    if((error) || (ret_class != class)) return 0;
+    else return 1;
+}
+
+/* Get propery */
+inline char *get_item_property(struct collection_item *ci,int *property_len)
+{
+    if(property_len != NULL) *property_len = ci->property_len;
+    return ci->property;
+}
+
+/* Get type */
+inline int get_item_type(struct collection_item *ci)
+{
+    return ci->type;
+}
+
+/* Get length */
+inline int get_item_length(struct collection_item *ci)
+{
+    return ci->length;
+}
+
+/* Get data */
+void *get_item_data(struct collection_item *ci)
+{
+    return ci->data;
+}
+
+
+/* Set time stamp in the collection - FIXME move to another level */
+int set_timestamp(struct collection_item *ci,struct collection_item **timestr_ref,struct collection_item **timeint_ref)
+{
+    time_t utctime;
+    struct tm time_struct;
+    char time_array[TIME_ARRAY_SIZE+1];
+    int len;
+    struct collection_item *timestr = (struct collection_item *)(NULL);
+    struct collection_item *timeint = (struct collection_item *)(NULL);
+    int error = EOK;
+
+    TRACE_FLOW_STRING("set_timestamp","Entry point");
+
+    utctime = time(NULL);
+    localtime_r(&utctime,&time_struct);
+
+    len = strftime(time_array, TIME_ARRAY_SIZE, DATE_FORMAT, &time_struct);
+    if(len == 0) {
+        TRACE_ERROR_STRING("add_time","CODING ERROR - INCREASE THE BUFFER");
+        return EMSGSIZE;
+    }
+
+    TRACE_INFO_STRING("Timestamp:",time_array);
+
+    /* Check if we have the timestamp item already */
+    error = get_item(ci, TS_NAME, COL_TYPE_STRING,COL_TRAVERSE_IGNORE,&timestr);
+    if(error) {
+        TRACE_ERROR_NUMBER("search failed with error:",error);
+        return error;
+    }
+
+    if(timestr != (struct collection_item *)(NULL)) {
+        /* There is a timestamp */
+        free(timestr->data);
+        timestr->data = strdup(time_array);
+        if(timestr->data == NULL) {
+            TRACE_ERROR_NUMBER("failed to add timestamp property:",error);
+            return ENOMEM;
+        }
+        timestr->length = len+1;
+        *timestr_ref = timestr;
+    }
+    else {
+        /* Add timestamp to the collection */
+        error = add_str_property_with_ref(ci,NULL, TS_NAME,time_array,len+1,timestr_ref);
+        if(error) {
+            TRACE_ERROR_NUMBER("failed to add timestamp property:",error);
+            return error;
+        }
+    }
+
+    /* Check if we have the time item already */
+    error = get_item(ci, T_NAME, COL_TYPE_INTEGER,COL_TRAVERSE_IGNORE,&timeint);
+    if(error) {
+        TRACE_ERROR_NUMBER("search failed with error:",error);
+        return error;
+    }
+
+    if(timeint != (struct collection_item *)(NULL)) {
+        /* There is a time property */
+        *((int *)(timeint->data)) = utctime;
+        *timeint_ref = timeint;
+    }
+    else {
+        /* Add time to the collection */
+        error = add_int_property_with_ref(ci,NULL, T_NAME,utctime,timeint_ref);
+        if(error) {
+            TRACE_ERROR_NUMBER("failed to add time property:",error);
+            return error;
+        }
+    }
+
+    TRACE_FLOW_STRING("set_timestamp","Exit point");
+    return EOK;
+}
+