--- /dev/null
+
+// huffware script: data cow, by fred huffhines.
+//
+// a data cow is a script that manages a list of text items. it allows an object
+// to offload the memory burden of managing a list of items, since LSL is very tight
+// on memory, even when compiled to mono.
+//
+// this script is licensed by the GPL v3 which is documented at: http://www.gnu.org/licenses/gpl.html
+// do not use it in objects without fully realizing you are implicitly accepting that license.
+//
+
+// global variables.
+
+list the_list;
+ // the main list that we manage here. we support adding to it, retrieving it
+ // and modifying it via our API.
+list the_names;
+ // the short names for each item in our list. we are basically supporting a
+ // symbol table data structure here.
+
+// link message API for the data cow library.
+//////////////
+// do not redefine these constants.
+integer DATA_COW_HUFFWARE_ID = 10017;
+ // the unique id within the huffware system for the jaunt script to
+ // accept commands on. this is used in llMessageLinked as the num parameter.
+string HUFFWARE_PARM_SEPARATOR = "{~~~}";
+ // this pattern is an uncommon thing to see in text, so we use it to separate
+ // our commands in link messages.
+///string HUFFWARE_ITEM_SEPARATOR = "{|||}";
+ // used to separate lists of items from each other when stored inside a parameter.
+ // this allows lists to be passed as single string parameters if needed.
+integer REPLY_DISTANCE = 100008; // offset added to service's huffware id in reply IDs.
+//////////////
+//
+string RESET_LIST_COMMAND = "reset_L";
+ // flushes out the currently held list. does not send a reply.
+string ADD_ITEM_COMMAND = "add_I";
+ // adds items to the list. this is a list of pairs of name/value, where the name is
+ // how the item will be looked up from the list, and the value is the contents to be stored.
+ // this command has no reply.
+string REMOVE_ITEM_COMMAND = "rm_I";
+ // accepts a list of names for items. all the mentioned ones will be removed from the list.
+ // this command also has no reply.
+string GET_COW_LENGTH = "get_Lc";
+ // returns a single integer which is the length of the cow's list currently.
+string GET_ITEM_COMMAND = "get_I";
+ // retrieves the item's contents for a given name. first parm is the name. if there
+ // are other parameters, then they are taken as other items to return also.
+ // the return data will be pairs of <name, entry> for each of the names in the request
+ // that is not empty. note that you can use an integer index by prefacing it with a
+ // '#' sign. for example, asking for item "#32" will return index 32 in the list of items.
+string TAGGED_GET_ITEM_COMMAND = "get_T";
+ // like get item, except the first parameter is an identifier that the caller wants to
+ // use to tag this request. the other parameters are still taken as names. the response
+ // will contain the tag as the first item, then the <name, entry> pairs that were found.
+//////////////
+
+// sets up the data cow for business.
+initialize()
+{
+ // flush all contents.
+ the_list = [];
+ the_names = [];
+}
+
+// find a named item in our list, if it exists.
+integer lookup_item(string name)
+{
+ integer indy;
+ if (llGetSubString(name, 0, 0) == "#") {
+ // our special sign for just using an index.
+ indy = (integer)llGetSubString(name, 1, -1);
+ if ( (indy >= 0) && (indy < llGetListLength(the_names)) ) return indy;
+ } else {
+ for (indy = 0; indy < llGetListLength(the_names); indy++) {
+ if (name == llList2String(the_names, indy)) return indy; // we know where it is now.
+ }
+ }
+ return -1; // never found it.
+}
+
+// places a named item in our list. if there's an existing item with
+// that name, then it's replaced.
+integer global_mem_complained = FALSE;
+add_item(string name, string content)
+{
+ if (llGetFreeMemory() < 2000) {
+ if (!global_mem_complained) {
+ global_mem_complained = TRUE;
+ llOwnerSay("out of memory at " + name);
+ }
+ return;
+ }
+ integer current = lookup_item(name);
+ if (current < 0) {
+//llOwnerSay("new item: " + name);
+ // this is a new item.
+ the_names += name;
+ the_list += content;
+ } else {
+//llOwnerSay("reusing slot " + (string)current + " for " + name);
+ // this is an old item to be replaced.
+ the_list = chop_list(the_list, 0, current - 1)
+ + [ content ]
+ + chop_list(the_list, current + 1, llGetListLength(the_list) - 1);
+ }
+//log_it("mem=" + (string)llGetFreeMemory());
+}
+
+// deletes an existing item if possible. TRUE is returned on success.
+integer remove_item(string name)
+{
+ integer indy = lookup_item(name);
+ if (indy < 0) return FALSE; // not present.
+ // found our sad whackee. we know the name and content should be
+ // stored at the exact same index in the two lists.
+ the_names = chop_list(the_names, 0, indy - 1)
+ + chop_list(the_names, indy + 1, llGetListLength(the_names) - 1);
+ the_list = chop_list(the_list, 0, indy - 1)
+ + chop_list(the_list, indy + 1, llGetListLength(the_list) - 1);
+ return TRUE; // all done here.
+}
+
+// supports our link message API by answering requests from clients.
+handle_link_message(integer sender, integer num, string msg, key id)
+{
+ if (num != DATA_COW_HUFFWARE_ID) return; // not for us.
+//log_it("hlm--mem free=" + (string)llGetFreeMemory());
+//log_it("rcvd: " + msg + " " + (string)num + " " + (string)id);
+ if (msg == RESET_LIST_COMMAND) {
+ initialize();
+ } else if (msg == ADD_ITEM_COMMAND) {
+ list parms = llParseString2List(id, [HUFFWARE_PARM_SEPARATOR], []);
+ integer indy;
+ for (indy = 0; indy < llGetListLength(parms); indy += 2) {
+ add_item(llList2String(parms, indy), llList2String(parms, indy + 1));
+ }
+ } else if (msg == REMOVE_ITEM_COMMAND) {
+ list parms = llParseString2List(id, [HUFFWARE_PARM_SEPARATOR], []);
+ integer indy;
+ for (indy = 0; indy < llGetListLength(parms); indy++) {
+ remove_item(llList2String(parms, indy));
+ }
+ } else if (msg == GET_COW_LENGTH) {
+ list parms = llParseString2List(id, [HUFFWARE_PARM_SEPARATOR], []);
+ string tag = llList2String(parms, 0);
+ list to_reply;
+ if (tag != "") to_reply = [ tag ];
+ to_reply += [ llGetListLength(the_list) ];
+ send_reply(LINK_THIS, to_reply, msg);
+ } else if ( (msg == GET_ITEM_COMMAND) || (msg == TAGGED_GET_ITEM_COMMAND) ) {
+ list parms = llParseString2List(id, [HUFFWARE_PARM_SEPARATOR], []);
+ integer indy;
+ string tag;
+ if (msg == TAGGED_GET_ITEM_COMMAND) {
+ // extract the tag, if they want that type of command handling.
+ tag = llList2String(parms, 0);
+ parms = llDeleteSubList(parms, 0, 0);
+ }
+ list to_reply;
+ // make sure we return the tag if they gave us one.
+ if (tag != "") to_reply = [ tag ];
+ for (indy = 0; indy < llGetListLength(parms); indy++) {
+ // iterate through the parameters and reply about any that we find.
+ integer found_posn = lookup_item(llList2String(parms, indy));
+ if (found_posn >= 0) {
+ // this item did exist.
+ to_reply += [ llList2String(the_names, found_posn), llList2String(the_list, found_posn) ];
+ }
+ }
+ send_reply(LINK_THIS, to_reply, msg);
+ }
+}
+
+//////////////
+// from hufflets...
+//
+//integer debug_num = 0;
+
+// a debugging output method. can be disabled entirely in one place.
+//log_it(string to_say)
+//{
+// debug_num++;
+// // tell this to the owner.
+// llOwnerSay(llGetScriptName() + "[" + (string)debug_num + "] " + to_say);
+// // say this on open chat, but use an unusual channel.
+//// llSay(108, llGetScriptName() + "[" + (string)debug_num + "] " + to_say);
+//}
+
+// returns the portion of the list between start and end, but only if they are
+// valid compared with the list length. an attempt to use negative start or
+// end values also returns a blank list.
+list chop_list(list to_chop, integer start, integer end)
+{
+ integer last_len = llGetListLength(to_chop) - 1;
+ if ( (start < 0) || (end < 0) || (start > last_len) || (end > last_len) ) return [];
+ return llList2List(to_chop, start, end);
+}
+
+// a simple version of a reply for a command that has been executed. the parameters
+// might contain an outcome or result of the operation that was requested.
+send_reply(integer destination, list parms, string command)
+{
+ llMessageLinked(destination, DATA_COW_HUFFWARE_ID + REPLY_DISTANCE,
+ command, llDumpList2String(parms, HUFFWARE_PARM_SEPARATOR));
+}
+
+//
+// end hufflets
+//////////////
+
+default
+{
+ state_entry() { if (llSubStringIndex(llGetObjectName(), "huffotronic") < 0) state real_default; }
+ on_rez(integer parm) { state rerun; }
+}
+state rerun { state_entry() { state default; } }
+
+state real_default
+{
+ state_entry() { initialize(); }
+
+ link_message(integer sender, integer num, string msg, key id)
+ { handle_link_message(sender, num, msg, id); }
+}
+
projects / feisty_meow.git / blobdiff