Added history processing.

server/src/chat.c

@@ -1,4 +1,5 @@
 #include "include/chat.h"
+#include "include/data.h"
 #include "include/session.h"
 
 #include <ctype.h>
@@ -8,6 +9,38 @@
 #include <time.h>
 #include <yyjson.h>
 
+MsgData* chat_history[CHAT_HISTORY_SZ] = {NULL};
+size_t chat_history_head = 0;
+
+MsgData* chat_history_msg_add(MsgData* msg) {
+    if (chat_history_head < CHAT_HISTORY_SZ - 1) {
+        chat_history[chat_history_head] = msg;
+        chat_history_head++;
+    } else if (chat_history_head == CHAT_HISTORY_SZ - 1) {
+        chat_history[chat_history_head] = msg;
+        chat_history_head = 0;
+    } else {
+        exit(132); // Bad.
+    }
+
+    return msg;
+}
+
+MsgData** chat_history_nice(void) {
+    MsgData** msgs = calloc(CHAT_HISTORY_SZ, sizeof(MsgData*));
+
+    size_t i = chat_history_head, j = 0;
+    while (true) {
+        if (!chat_history[i]) break;
+        msgs[j] = chat_history[i];
+        i = (i + 1) % CHAT_HISTORY_SZ;
+        j++;
+        if (chat_history_head == i) break;
+    }
+
+    return msgs;
+}
+
 static size_t next_msg_id = 1;
 
 // History buffer for last 100 messages.

server/src/include/chat.h

@@ -1,7 +1,23 @@
 #ifndef CHAT_H
 #define CHAT_H
 
+#include "data.h"
+
 #include <libwebsockets.h>
+#include <stddef.h>
+#include <stdbool.h>
+
+// Message history (ring).
+#define CHAT_HISTORY_SZ 128
+extern MsgData* chat_history[CHAT_HISTORY_SZ];
+extern size_t chat_history_head; // Points to the oldest message, or NULL.
+
+// Add message to history ring.
+MsgData* chat_history_msg_add(MsgData* msg);
+
+// Get a list of messages in order.
+MsgData** chat_history_nice(void);
+
 
 /**
  * cb_chat - libwebsockets protocol callback for COMS chat.