server: Send _push online messages on online change

4 files changed, 107 insertions, 2 deletions

diff --git a/broadcast.c b/broadcast.c
new file mode 100644
index 0000000..0517dc3
--- /dev/null
+++ b/broadcast.c
@@ -0,0 +1,89 @@
+#include <string.h>
+#include "broadcast.h"
+#include "db.h"
+#include "net.h"
+#include "user_data.h"
+
+
+// Returns whether value was new and therefore inserted into the list.
+// If already present, does nothing and returns false.
+// Assumes enough space for the possible new item.
+static bool sorted_insert(i64 *buf,i64 len,i64 value){
+	if(len==0){
+		buf[0]=value;
+		return true;
+	}
+	i64 L=0,H=len-1;
+	if(buf[L]==value||buf[H]==value)return false;
+	if(value<buf[L]){
+		memmove(buf+1,buf,len*sizeof(i64));
+		buf[0]=value;
+		return true;
+	}
+	if(value>buf[H]){
+		buf[len]=value;
+		return true;
+	}
+	while(L<H){
+		i64 M=L+(H-L)/2;
+		if(buf[M]==value)return false;
+		if(buf[M]<value){
+			L=M+1;
+			if(buf[L]>value)break;
+		} else if(buf[M]>value){
+			H=M-1;
+			if(buf[H]<value){
+				L=M;
+				break;
+			}
+		}
+	}
+	if(buf[L]==value)return false;
+	// We insert left of L
+	memmove(buf+L+1,buf+L,len-L);
+	buf[L]=value;
+	return true;
+}
+
+void broadcast_online_change(i64 userid){
+	i64 seencap=16,seenlen=0;
+	i64 *seen=malloc(seencap,i64);
+
+	struct db_room_list rooms=db_list_rooms(userid);
+	for(i64 i=0;i<rooms.count;i++){
+		struct db_user_list members=db_list_members(rooms.list[i].id);
+		for(i64 j=0;j<members.count;j++){
+			if(members.list[j].id==userid)continue;
+			i64 nfds;
+			(void)userdata_online(members.list[j].id,&nfds);
+			if(nfds==0)continue;
+			if(seenlen==seencap){
+				seencap*=2;
+				seen=realloc(seen,seencap,i64);
+			}
+			bool inserted=sorted_insert(seen,seenlen,members.list[j].id);
+			seenlen+=inserted;
+		}
+		db_nullify_user_list(members);
+	}
+	db_nullify_room_list(rooms);
+
+	char *name=db_get_username(userid);
+	i64 numonline;
+	(void)userdata_online(userid,&numonline);
+
+	char *buf;
+	i64 len=asprintf(&buf,"_push online %" PRIi64 " %s\n",numonline,name);
+	free(name);
+
+	for(i64 i=0;i<seenlen;i++){
+		i64 nfds;
+		const int *fds=userdata_online(seen[i],&nfds);
+		for(i64 j=0;j<nfds;j++){
+			net_send_raw_text(fds[j],buf,len);
+		}
+	}
+
+	free(buf);
+	free(seen);
+}
diff --git a/broadcast.h b/broadcast.h
new file mode 100644
index 0000000..6ad5aad
--- /dev/null
+++ b/broadcast.h
@@ -0,0 +1,6 @@
+#pragma once
+
+#include "global.h"
+
+
+void broadcast_online_change(i64 userid);
diff --git a/command.c b/command.c
index e66eb12..1bbde10 100644
--- a/command.c
+++ b/command.c
@@ -4,6 +4,7 @@
 #include <errno.h>
 #include <sys/time.h>
 #include <sys/socket.h>
+#include "broadcast.h"
 #include "command.h"
 #include "db.h"
 #include "net.h"
@@ -38,11 +39,13 @@ static bool cmd_login(struct conn_data *data,const char *tag,const char **args){
 	free(pass);
 	if(data->userid!=-1){
 		userdata_unregister(data->userid,data->fd);
+		broadcast_online_change(data->userid);
 	}
 	if(success){
 		data->userid=userid;
 		userdata_register(userid,data->fd);
 		net_send_ok(data->fd,tag);
+		broadcast_online_change(userid);
 	} else {
 		data->userid=-1;
 		net_send_error(data->fd,tag,"Incorrect password");
diff --git a/main.c b/main.c
index 622e1b9..5afece8 100644
--- a/main.c
+++ b/main.c
@@ -7,6 +7,7 @@
 #include <netinet/in.h>
 #include <errno.h>
 #include <assert.h>
+#include "broadcast.h"
 #include "command.h"
 #include "conn_data.h"
 #include "db.h"
@@ -53,7 +54,10 @@ static void delete_conn_data(int fd){
 	struct hash_item *item=conn_hash[fd%CONN_HASH_SIZE];
 	assert(item);
 	if(item->cd.fd==fd){
-		if(item->cd.userid!=-1)userdata_unregister(item->cd.userid,fd);
+		if(item->cd.userid!=-1){
+			userdata_unregister(item->cd.userid,fd);
+			broadcast_online_change(item->cd.userid);
+		}
 		conn_hash[fd%CONN_HASH_SIZE]=item->next;
 		conn_data_nullify(&item->cd);
 		free(item);
@@ -66,7 +70,10 @@ static void delete_conn_data(int fd){
 	}
 	assert(parent);
 	assert(item);
-	if(item->cd.userid!=-1)userdata_unregister(item->cd.userid,fd);
+	if(item->cd.userid!=-1){
+		userdata_unregister(item->cd.userid,fd);
+		broadcast_online_change(item->cd.userid);
+	}
 	conn_data_nullify(&item->cd);
 	parent->next=item->next;
 	free(item);