From 06a01f2b4b5261cb277b29d0f73bc3526b018252 Mon Sep 17 00:00:00 2001
From: Philippe Pittoli <karchnu@karchnu.fr>
Date: Fri, 20 Jan 2023 04:04:12 +0100
Subject: [PATCH] Add several example programs.

---
 zig-impl/other/double-close.zig             | 11 ++++
 zig-impl/other/example-hexdump.zig          |  8 +++
 zig-impl/other/rcv-fd.zig                   | 57 +++++++++++++++++++++
 zig-impl/other/snd-fd.zig                   | 43 ++++++++++++++++
 zig-impl/other/test-fn.zig                  | 25 +++++++++
 zig-impl/other/test-tcp-client.zig          | 49 ++++++++++++++++++
 zig-impl/other/test-tcp-server.zig          | 57 +++++++++++++++++++++
 zig-impl/other/testme.zig                   | 22 ++++++++
 zig-impl/other/write-tcpd-pong-messages.zig | 31 +++++++++++
 9 files changed, 303 insertions(+)
 create mode 100644 zig-impl/other/double-close.zig
 create mode 100644 zig-impl/other/example-hexdump.zig
 create mode 100644 zig-impl/other/rcv-fd.zig
 create mode 100644 zig-impl/other/snd-fd.zig
 create mode 100644 zig-impl/other/test-fn.zig
 create mode 100644 zig-impl/other/test-tcp-client.zig
 create mode 100644 zig-impl/other/test-tcp-server.zig
 create mode 100644 zig-impl/other/testme.zig
 create mode 100644 zig-impl/other/write-tcpd-pong-messages.zig

diff --git a/zig-impl/other/double-close.zig b/zig-impl/other/double-close.zig
new file mode 100644
index 0000000..47180e2
--- /dev/null
+++ b/zig-impl/other/double-close.zig
@@ -0,0 +1,11 @@
+const std = @import("std");
+const print = std.debug.print;
+
+pub fn main() !u8 {
+    print("First close!\n", .{});
+    std.os.close(1);
+    print("SECOND close!\n", .{});
+    std.os.close(1);
+    print("Will it be printed?\n", .{});
+    return 0;
+}
diff --git a/zig-impl/other/example-hexdump.zig b/zig-impl/other/example-hexdump.zig
new file mode 100644
index 0000000..ea3a6a1
--- /dev/null
+++ b/zig-impl/other/example-hexdump.zig
@@ -0,0 +1,8 @@
+const msg_type    = @intToEnum(Message.Type, try reader.readByte());
+try writer.writeByte(@enumToInt(self.t));
+
+var hexbuf: [4000]u8 = undefined;
+var hexfbs = std.io.fixedBufferStream(&hexbuf);
+var hexwriter = hexfbs.writer();
+try hexdump.hexdump(hexwriter, "Message.read input buffer", buffer);
+print("{s}\n", .{hexfbs.getWritten()});
diff --git a/zig-impl/other/rcv-fd.zig b/zig-impl/other/rcv-fd.zig
new file mode 100644
index 0000000..6a91269
--- /dev/null
+++ b/zig-impl/other/rcv-fd.zig
@@ -0,0 +1,57 @@
+const std = @import("std");
+const net = std.net;
+const print = std.debug.print;
+
+const receive_fd = @import("./exchange-fd.zig").receive_fd;
+
+fn disconnect(stream: *net.StreamServer) void { stream.close(); }
+
+fn server_init() net.StreamServer {
+    // no reuse_address and default kernel_backlog
+    return net.StreamServer.init(.{});
+}
+
+fn waiting_for_connection(stream: *net.StreamServer
+  , path: []const u8) !net.StreamServer.Connection {
+    var address = try net.Address.initUnix(path);
+    try stream.listen(address);
+    return stream.accept();
+}
+
+fn remove_unix_socket(path: []const u8) void {
+    std.fs.deleteFileAbsolute(path) catch |err| switch(err) {
+        else => { print("error: {}\n", .{err}); }
+    };
+}
+
+fn add_line_from_fd(fd: i32) !void {
+    _ = try std.os.write(fd, "SECOND LINE\n");
+    std.os.close(fd);
+}
+
+pub fn main() !u8 {
+    var path = "/tmp/TEST_EXCHANGE_FD";
+
+    print("Init UNIX server to {s}...\n", .{path});
+    var stream = server_init();
+    defer stream.deinit();
+
+    print("Waiting for a connection...\n", .{});
+    var connection = try waiting_for_connection(&stream, path);
+    defer remove_unix_socket(path);
+
+    print("Someone is connected! Receiving a file descriptor...\n", .{});
+    var msgbuffer: [1500]u8 = undefined;
+    var msgsize: usize = 0;
+    var fd = try receive_fd(connection.stream.handle, msgbuffer[0..], &msgsize);
+    print("received fd: {}, payload: {s}\n", .{fd, msgbuffer[0..msgsize - 1]});
+
+    print("FD received, writing a line into the file...\n", .{});
+    try add_line_from_fd(fd);
+
+    print("Disconnection...\n", .{});
+    disconnect(&stream);
+
+    print("Disconnected!\n", .{});
+    return 0;
+}
diff --git a/zig-impl/other/snd-fd.zig b/zig-impl/other/snd-fd.zig
new file mode 100644
index 0000000..5365194
--- /dev/null
+++ b/zig-impl/other/snd-fd.zig
@@ -0,0 +1,43 @@
+const std = @import("std");
+const net = std.net;
+
+const send_fd = @import("./exchange-fd.zig").send_fd;
+
+const print = std.debug.print;
+
+fn disconnect(stream: net.Stream) void { stream.close(); }
+
+fn connect(path: []const u8) !net.Stream {
+    return try net.connectUnixSocket(path);
+}
+
+fn add_line_in_file() !void {
+    var cwd = std.fs.cwd();
+    var f = try cwd.createFile("some-file.log", .{.read = true});
+    defer f.close();
+
+    var writer = f.writer();
+    try writer.print("hello\n", .{});
+}
+
+pub fn main() !u8 {
+    var path = "/tmp/TEST_EXCHANGE_FD";
+
+    print("Connection to {s}...\n", .{path});
+    var stream = try connect(path);
+
+    print("Connected! Opening a file...\n", .{});
+    var file = try std.fs.cwd().createFile("some-file.log", .{.read = true});
+    defer file.close();
+
+    print("File opened! Writing some data into it...\n", .{});
+    var writer = file.writer();
+    try writer.print("hello this is the first process\n", .{});
+
+    print("Data written! Sending its fd...\n", .{});
+    send_fd(stream.handle, "hello this is the payload", file.handle);
+    print("Sent fd! Disconnection...\n", .{});
+    disconnect(stream);
+    print("Disconnected!\n", .{});
+    return 0;
+}
diff --git a/zig-impl/other/test-fn.zig b/zig-impl/other/test-fn.zig
new file mode 100644
index 0000000..882be4c
--- /dev/null
+++ b/zig-impl/other/test-fn.zig
@@ -0,0 +1,25 @@
+const std = @import("std");
+const hexdump = @import("./hexdump.zig");
+const net = std.net;
+const fmt = std.fmt;
+const os = std.os;
+
+const print = std.debug.print;
+
+fn say_hello(some_number: i32) void {
+    print ("hello number {}\n", .{some_number});
+}
+
+fn say_coucou(some_number: i32) void {
+    print ("coucou number {}\n", .{some_number});
+}
+
+pub fn main() !u8 {
+    var fp: *const fn (i32) void = say_hello;
+    // print ("currently fp {any}\n", .{fp});
+    fp(10);
+    fp = say_coucou;
+    // print ("currently fp {p}\n", .{fp.?});
+    fp(20);
+    return 0;
+}
diff --git a/zig-impl/other/test-tcp-client.zig b/zig-impl/other/test-tcp-client.zig
new file mode 100644
index 0000000..d51b1e8
--- /dev/null
+++ b/zig-impl/other/test-tcp-client.zig
@@ -0,0 +1,49 @@
+const std = @import("std");
+const net = std.net;
+const fmt = std.fmt;
+const os = std.os;
+
+const print = std.debug.print;
+const testing = std.testing;
+const print_eq = @import("./util.zig").print_eq;
+const URI = @import("./util.zig").URI;
+
+fn connect_tcp(allocator: std.mem.Allocator) !net.Stream {
+    var buffer: [1000]u8 = undefined;
+    var fbs = std.io.fixedBufferStream(&buffer);
+    var writer = fbs.writer();
+
+    var address = std.process.getEnvVarOwned(allocator, "ADDRESS") catch |err| switch(err) {
+        error.EnvironmentVariableNotFound => blk: {
+            print("no ADDRESS envvar: connecting on 127.0.0.1:9000\n", .{});
+            break :blk try allocator.dupe(u8, "127.0.0.1:9000");
+        },
+        else => { return err; },
+    };
+    defer allocator.free(address);
+
+    try writer.print("{s}", .{address});
+    var tcp_address = fbs.getWritten();
+
+    var iterator = std.mem.split(u8, tcp_address, ":");
+    var real_tcp_address = iterator.first();
+    var real_tcp_port = try std.fmt.parseUnsigned(u16, iterator.rest(), 10);
+
+    print ("TCP address [{s}] port [{}]\n", .{real_tcp_address, real_tcp_port});
+
+    var socket_addr = try net.Address.parseIp(real_tcp_address, real_tcp_port);
+    var stream = try net.tcpConnectToAddress(socket_addr);
+
+    return stream;
+}
+
+pub fn main() !u8 {
+    const config = .{.safety = true};
+    var gpa = std.heap.GeneralPurposeAllocator(config){};
+    defer _ = gpa.deinit();
+    const allocator = gpa.allocator();
+    var stream = try connect_tcp(allocator);
+    _ = try stream.write("coucou");
+    stream.close();
+    return 0;
+}
diff --git a/zig-impl/other/test-tcp-server.zig b/zig-impl/other/test-tcp-server.zig
new file mode 100644
index 0000000..bd1ba85
--- /dev/null
+++ b/zig-impl/other/test-tcp-server.zig
@@ -0,0 +1,57 @@
+const std = @import("std");
+const net = std.net;
+const fmt = std.fmt;
+const os = std.os;
+
+const print = std.debug.print;
+const testing = std.testing;
+const print_eq = @import("./util.zig").print_eq;
+const URI = @import("./util.zig").URI;
+
+fn init_tcp_server(allocator: std.mem.Allocator) !net.StreamServer {
+    var buffer: [1000]u8 = undefined;
+    var fbs = std.io.fixedBufferStream(&buffer);
+    var writer = fbs.writer();
+
+    var address = std.process.getEnvVarOwned(allocator, "ADDRESS") catch |err| switch(err) {
+        error.EnvironmentVariableNotFound => blk: {
+            print("no ADDRESS envvar: TCPd will listen on 127.0.0.1:9000\n", .{});
+            break :blk try allocator.dupe(u8, "127.0.0.1:9000");
+        },
+        else => { return err; },
+    };
+    defer allocator.free(address);
+
+    try writer.print("{s}", .{address});
+    var tcp_address = fbs.getWritten();
+
+    var iterator = std.mem.split(u8, tcp_address, ":");
+    var real_tcp_address = iterator.first();
+    var real_tcp_port = try std.fmt.parseUnsigned(u16, iterator.rest(), 10);
+
+    print ("TCP address [{s}] port [{}]\n", .{real_tcp_address, real_tcp_port});
+
+    var server = net.StreamServer.init(.{.reuse_address = true});
+    var socket_addr = try net.Address.parseIp(real_tcp_address, real_tcp_port);
+    try server.listen(socket_addr);
+
+    return server;
+}
+
+fn accept_read(server: *net.StreamServer) !void {
+    var client = try server.accept(); // net.StreamServer.Connection
+    var buffer: [1000]u8 = undefined;
+    var size = try client.stream.read(&buffer);
+    print ("received: {s}\n", .{buffer[0..size]});
+    client.stream.close();
+}
+
+pub fn main() !u8 {
+    const config = .{.safety = true};
+    var gpa = std.heap.GeneralPurposeAllocator(config){};
+    defer _ = gpa.deinit();
+    const allocator = gpa.allocator();
+    var streamserver = try init_tcp_server(allocator);
+    try accept_read(&streamserver);
+    return 0;
+}
diff --git a/zig-impl/other/testme.zig b/zig-impl/other/testme.zig
new file mode 100644
index 0000000..10ad421
--- /dev/null
+++ b/zig-impl/other/testme.zig
@@ -0,0 +1,22 @@
+const std = @import("std");
+const hexdump = @import("./hexdump.zig");
+const net = std.net;
+const fmt = std.fmt;
+const os = std.os;
+
+const print = std.debug.print;
+const ipc = @import("./main.zig");
+const Message = ipc.Message;
+
+pub fn main() !u8 {
+    const config = .{.safety = true};
+    var gpa = std.heap.GeneralPurposeAllocator(config){};
+    defer _ = gpa.deinit();
+    const allocator = gpa.allocator();
+
+    var ctx = try ipc.Context.init(allocator);
+    ctx.deinit(); // There. Can't leak. Isn't Zig wonderful?
+
+    print("Goodbye\n", .{});
+    return 0;
+}
diff --git a/zig-impl/other/write-tcpd-pong-messages.zig b/zig-impl/other/write-tcpd-pong-messages.zig
new file mode 100644
index 0000000..af7de93
--- /dev/null
+++ b/zig-impl/other/write-tcpd-pong-messages.zig
@@ -0,0 +1,31 @@
+const std = @import("std");
+const ipc = @import("./ipc.zig");
+const hexdump = @import("./hexdump.zig");
+const print = std.debug.print;
+
+
+pub fn main() !void {
+    var allocator = std.heap.c_allocator;
+
+    var buffer = [_]u8{0} ** 10000;
+    var fbs = std.io.fixedBufferStream(&buffer);
+    var writer = fbs.writer();
+
+    var m = try ipc.Message.init (9, allocator, "hello this is me!");
+    defer m.deinit();
+
+    _ = try m.write(writer);
+
+    var msg_bytes = fbs.getWritten();
+
+    // var hexbuf: [4000]u8 = undefined;
+    // var hexfbs = std.io.fixedBufferStream(&hexbuf);
+    // var hexwriter = hexfbs.writer();
+    // try hexdump.hexdump(hexwriter, "What should be written in output", msg_bytes);
+    // print("{s}\n", .{hexfbs.getWritten()});
+
+    var out = std.io.getStdOut();
+    _ = try out.write("pong");
+    std.time.sleep(1_000_000_000); // wait for 1 seconds
+    _ = try out.write(msg_bytes);
+}