Merge pull request 'check protocol' (#3) from tcp_demo into main

Reviewed-on: http://198.12.122.141:3121/zig/nation/pulls/3

src/handle.zig

@@ -0,0 +1,82 @@
+const std = @import("std");
+const log = std.log;
+const net = std.net;
+const ArrayList = std.ArrayList;
+
+pub const Protocol = enum {
+    HTTP,
+    SSH,
+    // DNS,
+    // FTP,
+    // SMTP,
+    // IMAP,
+    // POP3,
+    Unknown,
+};
+
+const ProtocolMap = struct {
+    prefix: []const u8,
+    protocol: Protocol,
+};
+
+const ProtocolMappings = [_]ProtocolMap{
+    .{ .prefix = "HTTP/1.1", .protocol = .HTTP },
+    .{ .prefix = "GET", .protocol = Protocol.HTTP },
+    .{ .prefix = "HEAD", .protocol = Protocol.HTTP },
+    .{ .prefix = "POST", .protocol = Protocol.HTTP },
+    .{ .prefix = "PUT", .protocol = Protocol.HTTP },
+    .{ .prefix = "DELETE", .protocol = Protocol.HTTP },
+    .{ .prefix = "CONNECT", .protocol = Protocol.HTTP },
+    .{ .prefix = "OPTIONS", .protocol = Protocol.HTTP },
+    .{ .prefix = "TRACE", .protocol = Protocol.HTTP },
+    .{ .prefix = "PATCH", .protocol = Protocol.HTTP },
+    .{ .prefix = "SSH-", .protocol = Protocol.SSH },
+};
+
+/// ### check protocol
+///
+/// ### author
+/// * Shawn Jones
+fn detectApplicationLayerProtocol(data: []u8) Protocol {
+    for (ProtocolMappings) |mapping| {
+        if (std.mem.startsWith(u8, data, mapping.prefix)) {
+            return mapping.protocol;
+        }
+    }
+    return Protocol.Unknown;
+}
+
+pub fn handleClient(_: std.mem.Allocator, server: *net.Server) !void {
+    // var full_message = ArrayList(u8).init(allocator);
+    // defer full_message.deinit();
+
+    while (true) {
+        const client = try server.accept();
+        // log.info("has a client connected: {any}", .{client});
+        defer client.stream.close();
+        // [TODO 1] check protocol
+
+        var prefix: [10]u8 = undefined;
+        _ = try client.stream.read(&prefix);
+        log.info("prefix is {s}\n", .{prefix});
+        log.info("{?}\n", .{@TypeOf(prefix)});
+        const protocol: Protocol = detectApplicationLayerProtocol(&prefix);
+        log.info("the client using protocol is {?}\n", .{protocol});
+        if (protocol == Protocol.Unknown) {
+            log.err("Unsupport protocol!", .{});
+            continue;
+        }
+        // [TODO 2] forward data
+        // accept from client
+        // var message: [4]u8 = undefined;
+        // var total_len: usize = 0;
+        // r: while (true) {
+        //     const bytesRead = try client.stream.readAll(&message);
+        //     if (bytesRead == 0) break :r;
+        //     total_len += bytesRead;
+        //     std.debug.print("Received: {s}\n", .{message[0..bytesRead]});
+        //     try full_message.appendSlice(message[0..bytesRead]);
+        // }
+        // log.info("Full Message: {s}\n", .{full_message.items});
+    }
+}

src/server.zig

@@ -1,4 +1,5 @@
 const std = @import("std");
+const handle = @import("handle.zig");
 const log = std.log;
 const net = std.net;
 
@@ -10,7 +11,7 @@ pub fn main() !void {
     defer {
         _ = gpa.deinit();
     }
-    // const allocator = gpa.allocator();
+    const allocator = gpa.allocator();
     // listen to local ip:port
     const address = try net.Address.parseIp(ip, port);
     log.info("server listen to {s}:{d}", .{ ip, port });
@@ -18,19 +19,5 @@ pub fn main() !void {
     var server = try net.Address.listen(address, .{ .reuse_port = false });
     defer server.deinit();
 
-    while (true) {
-        // accept from client
-        const client = try server.accept();
-        log.info("has a client connected: {any}", .{client});
-        defer client.stream.close();
-
-        var message: [4]u8 = undefined;
-        var total_len: usize = 0;
-        r: while (true) {
-            const bytesRead = try client.stream.readAll(&message);
-            if (bytesRead == 0) break :r;
-            total_len += bytesRead;
-            std.debug.print("Received: {s}\n", .{message[0..bytesRead]});
-        }
-    }
+    try handle.handleClient(allocator, &server);
 }