Merge pull request #344 from DrDoof/feat/walk-l2

html: move the L2 table walk into a shared walkL2() helper

html/l2.js

@@ -1,7 +1,3 @@
-var l2GetInterval;
-var l2Entries = [];
-var l2CurrentEntry = 0;
-
 function fillStats() {
   var tbl = document.getElementById('statstable');
   if (!numPorts)
@@ -118,7 +114,6 @@ function fillL2(s)
   s = uniq(s);
   l2All = s;
   renderL2();
-  l2Entries = [];
 }
 
 function paintL2(tbl, s)
@@ -147,48 +142,20 @@ function paintL2(tbl, s)
 }
 
 function getL2() {
-  var xhttp = new XMLHttpRequest();
+  walkL2(function(entries, ok) {
-  xhttp.onreadystatechange = function() {
+    if (ok) {
-    if (this.readyState == 4 && this.status == 200) {
+      for (var i = 0; i < entries.length; i++)
-      var s = JSON.parse(xhttp.responseText);
+        entries[i].type = entries[i].type == "s" ? t('l2_static') : t('l2_learned');
-      var s = s.map(function(e) { 
+      fillL2(entries);
-        e.vlan = parseInt(e.vlan, 16);
-        e.idx = parseInt(e.idx, 16);
-        e.type = e.type == "s" ? t('l2_static') : t('l2_learned');
-        e.port = e.port == 9 ? 'CPU' : logToPhysPort[e.port];
-      return e;
-    });
-      l2Entries.push(...s);
-      if (l2Entries >= 4096) {
-        l2Entries = [];
-        l2CurrentEntry = 0;
-        clearInterval(l2GetInterval);
-        return;
-      }
-      var w = 0;
-      for (var i = l2Entries.length-1; i > 0; i--) {
-        if (l2Entries[0].idx == l2Entries[i].idx) {
-          w = 1;
-          break;
-        }
-      }
-      if (w) {
-        l2CurrentEntry = 0; 
-        fillL2(l2Entries);
-      } else {
-        l2CurrentEntry = s[s.length-1].idx + 1;
-      }
     }
-  };
+    setTimeout(getL2, 1000);
-  xhttp.open("GET", "/l2.json?idx=" + l2CurrentEntry, true);
+  });
-  xhttp.timeout = 1500; sendXHTTP(xhttp);
 }
 
 window.addEventListener("load", function() {
   update( () => {
     getL2();
     const interval = setInterval(update, 2000);
-    l2GetInterval = setInterval(getL2, 1000);
   });;
 });
 

html/main.js

@@ -285,3 +285,66 @@ function sendXHTTP(x)
   currentRequests.push(x);
 }
 
+
+function walkL2(onDone)
+{
+  var entries = [];
+  var idx = 0;
+  var tries = 0;
+
+  function retry() {
+    if (++tries < 3) {
+      setTimeout(page, 1000);
+      return;
+    }
+    onDone(entries, false);
+  }
+
+  function page() {
+    var xhttp = new XMLHttpRequest();
+    xhttp.onreadystatechange = function() {
+      if (this.readyState != 4)
+        return;
+      if (this.status != 200) {
+        retry();
+        return;
+      }
+      var s;
+      try {
+        s = JSON.parse(xhttp.responseText);
+      } catch (err) {
+        retry();
+        return;
+      }
+      tries = 0;
+      s = s.map(function(e) {
+        e.vlan = parseInt(e.vlan, 16);
+        e.idx = parseInt(e.idx, 16);
+        e.port = e.port == 9 ? 'CPU' : logToPhysPort[e.port];
+        return e;
+      });
+      if (!s.length) {
+        onDone(entries, true);
+        return;
+      }
+      entries.push(...s);
+      for (var i = entries.length - 1; i > 0; i--) {
+        if (entries[0].idx == entries[i].idx) {
+          onDone(entries, true);
+          return;
+        }
+      }
+      if (entries.length >= 4096) {
+        onDone(entries, true);
+        return;
+      }
+      idx = s[s.length - 1].idx + 1;
+      setTimeout(page, 1000);
+    };
+    xhttp.open("GET", "/l2.json?idx=" + idx, true);
+    xhttp.timeout = 1500;
+    sendXHTTP(xhttp);
+  }
+
+  page();
+}

httpd/page_impl.c

@@ -356,6 +356,7 @@ void send_l2(uint16_t idx)
 	 */
 	__xdata uint16_t entry = idx & 0xfff;
 	__xdata uint16_t first_entry = 0xffff; // An illegal entry index
+	bool first = true;
 	char_to_html('[');
 	while (1) {
 		entries_left--;
@@ -369,9 +370,22 @@ void send_l2(uint16_t idx)
 		} while (sfr_data[3] & TBL_EXECUTE);
 
 		reg_read_m(RTL837x_L2_DATA_OUT_B);
-		if ((sfr_data[0] & 0x20)) {	// Check entry is valid
+		bool valid = (sfr_data[0] & 0x20) != 0;
+		if (valid) {
+			/* separator + 74-byte worst-case entry + closing "]" */
+			if (slen + 76 > TCP_OUTBUF_SIZE)
+				break;
+			if (!first)
+				char_to_html(',');
+			first = false;
+
+			// VLAN, taken from the read above instead of reading the register twice
+			slen += strtox(outbuf + slen, "{\"vlan\":\"");
+			charhex_to_html(sfr_data[0] & 0x0f);
+			byte_to_html(sfr_data[1]);
+
 			// MAC
-			slen += strtox(outbuf + slen, "{\"mac\":\"");
+			slen += strtox(outbuf + slen, "\",\"mac\":\"");
 			byte_to_html(sfr_data[2]); char_to_html(':');
 			byte_to_html(sfr_data[3]); char_to_html(':');
 			port = (sfr_data[0] >> 6) & 0x3;
@@ -381,12 +395,6 @@ void send_l2(uint16_t idx)
 			byte_to_html(sfr_data[2]); char_to_html(':');
 			byte_to_html(sfr_data[3]);
 
-			// VLAN
-			slen += strtox(outbuf + slen, "\",\"vlan\":\"");
-			reg_read_m(RTL837x_L2_DATA_OUT_B);
-			charhex_to_html(sfr_data[0] & 0x0f);
-			byte_to_html(sfr_data[1]);
-
 			// type
 			reg_read_m(RTL837x_L2_DATA_OUT_C);
 			if (sfr_data[2] & 0x1)
@@ -396,32 +404,26 @@ void send_l2(uint16_t idx)
 
 			port |= (sfr_data[3] & 0x3) << 2;
 			itoa_html(port);
+		}
 
-			// Index
+		// Index
-			reg_read_m(RTL837x_TBL_DATA_0);
+		reg_read_m(RTL837x_TBL_DATA_0);
-			entry = (((uint16_t)sfr_data[2] & 0x0f) << 8) | sfr_data[3];
+		entry = (((uint16_t)sfr_data[2] & 0x0f) << 8) | sfr_data[3];
+		if (valid) {
 			slen += strtox(outbuf + slen, ",\"idx\":\"");
 			byte_to_html(entry >> 8);
 			byte_to_html(entry);
 			char_to_html('"');
 			char_to_html('}');
-			entry += 1; // We want the next entry following after the current entry
-		} else {
-			reg_read_m(RTL837x_TBL_DATA_0);
-			entry = (((uint16_t)sfr_data[2] & 0x0f) << 8) | sfr_data[3] + 1;
 		}
-		if (first_entry == 0xffff) {
+		entry += 1; // We want the next entry following after the current entry
-			char_to_html(',');
+
+		if (first_entry == 0xffff)
 			first_entry = entry;
-		} else {
+		else if (first_entry == entry || !entries_left)
-			if (first_entry == entry || !entries_left) {
+			break;
-				char_to_html(']');
-				break;
-			} else {
-				char_to_html(',');
-			}
-		}
 	}
+	char_to_html(']');
 }