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Hello world调用外部库函数内存泄露检测C 互操作性Zigg Zagg泛型在 Zig 中使用 cURL
Hello worldA minimal example printing hello world.
hello-world.zigconst std = @import("std");
pub fn main() !void {
const stdout = std.io.getStdOut().writer();
try stdout.print("hello world!\n", .{});
}Shell$ zig build-exe hello-world.zig
$ ./hello-world
hello world!
调用外部库函数所有的系统 API 函数都可以通过这种方式调用，您不需要库绑定来与它们交互。
windows-msgbox.zigconst win = @import("std").os.windows;
extern "user32" fn MessageBoxA(?win.HWND, [*:0]const u8, [*:0]const u8, u32) callconv(win.WINAPI) i32;
pub fn main() !void {
_ = MessageBoxA(null, "world!", "Hello", 0);
}Shell$ zig test windows-msgbox.zig
All 0 tests passed.
内存泄露检测使用 std.heap.GeneralPurposeAllocator 来检测双重释放和内存泄露。
memory-leak.zigconst std = @import("std");
pub fn main() !void {
var general_purpose_allocator = std.heap.GeneralPurposeAllocator(.{}){};
defer std.debug.assert(general_purpose_allocator.deinit() == .ok);
const gpa = general_purpose_allocator.allocator();
const u32_ptr = try gpa.create(u32);
_ = u32_ptr; // silences unused variable error
// oops I forgot to free!
}Shell$ zig build-exe memory-leak.zig
$ ./memory-leak
error(gpa): memory address 0x7ff322440000 leaked:
/home/ci/actions-runner-website/_work/www.ziglang.org/www.ziglang.org/zig-code/samples/memory-leak.zig:9:35: 0x10e0237 in main (memory-leak)
const u32_ptr = try gpa.create(u32);
^
/home/ci/deps/zig-linux-x86_64-0.14.0/lib/std/start.zig:656:37: 0x10e010a in posixCallMainAndExit (memory-leak)
const result = root.main() catch |err| {
^
/home/ci/deps/zig-linux-x86_64-0.14.0/lib/std/start.zig:271:5: 0x10dfcbd in _start (memory-leak)
asm volatile (switch (native_arch) {
^
thread 1954844 panic: reached unreachable code
/home/ci/deps/zig-linux-x86_64-0.14.0/lib/std/debug.zig:522:14: 0x104ae2d in assert (memory-leak)
if (!ok) unreachable; // assertion failure
^
/home/ci/actions-runner-website/_work/www.ziglang.org/www.ziglang.org/zig-code/samples/memory-leak.zig:5:27: 0x10e02b5 in main (memory-leak)
defer std.debug.assert(general_purpose_allocator.deinit() == .ok);
^
/home/ci/deps/zig-linux-x86_64-0.14.0/lib/std/start.zig:656:37: 0x10e010a in posixCallMainAndExit (memory-leak)
const result = root.main() catch |err| {
^
/home/ci/deps/zig-linux-x86_64-0.14.0/lib/std/start.zig:271:5: 0x10dfcbd in _start (memory-leak)
asm volatile (switch (native_arch) {
^
???:?:?: 0x0 in ??? (???)
(process terminated by signal)
C 互操作性导入 C 头文件并链接到 libc 和 raylib 的示例。
c-interop.zig// build with `zig build-exe cimport.zig -lc -lraylib`
const ray = @cImport({
@cInclude("raylib.h");
});
pub fn main() void {
const screenWidth = 800;
const screenHeight = 450;
ray.InitWindow(screenWidth, screenHeight, "raylib [core] example - basic window");
defer ray.CloseWindow();
ray.SetTargetFPS(60);
while (!ray.WindowShouldClose()) {
ray.BeginDrawing();
defer ray.EndDrawing();
ray.ClearBackground(ray.RAYWHITE);
ray.DrawText("Hello, World!", 190, 200, 20, ray.LIGHTGRAY);
}
}
Zigg ZaggZig 已为代码面试做了优化（并没有）。
ziggzagg.zigconst std = @import("std");
pub fn main() !void {
const stdout = std.io.getStdOut().writer();
var i: usize = 1;
while (i <= 16) : (i += 1) {
if (i % 15 == 0) {
try stdout.writeAll("ZiggZagg\n");
} else if (i % 3 == 0) {
try stdout.writeAll("Zigg\n");
} else if (i % 5 == 0) {
try stdout.writeAll("Zagg\n");
} else {
try stdout.print("{d}\n", .{i});
}
}
}Shell$ zig build-exe ziggzagg.zig
$ ./ziggzagg
1
2
Zigg
4
Zagg
Zigg
7
8
Zigg
Zagg
11
Zigg
13
14
ZiggZagg
16
泛型在 Zig 中，类型是编译期的值，我们使用返回类型的函数来实现泛型算法和数据结构。在此示例中，我们实现了一个简单的泛型队列并测试其行为。
generic-type.zigconst std = @import("std");
pub fn Queue(comptime Child: type) type {
return struct {
const Self = @This();
const Node = struct {
data: Child,
next: ?*Node,
};
gpa: std.mem.Allocator,
start: ?*Node,
end: ?*Node,
pub fn init(gpa: std.mem.Allocator) Self {
return Self{
.gpa = gpa,
.start = null,
.end = null,
};
}
pub fn enqueue(self: *Self, value: Child) !void {
const node = try self.gpa.create(Node);
node.* = .{ .data = value, .next = null };
if (self.end) |end| end.next = node //
else self.start = node;
self.end = node;
}
pub fn dequeue(self: *Self) ?Child {
const start = self.start orelse return null;
defer self.gpa.destroy(start);
if (start.next) |next|
self.start = next
else {
self.start = null;
self.end = null;
}
return start.data;
}
};
}
test "queue" {
var int_queue = Queue(i32).init(std.testing.allocator);
try int_queue.enqueue(25);
try int_queue.enqueue(50);
try int_queue.enqueue(75);
try int_queue.enqueue(100);
try std.testing.expectEqual(int_queue.dequeue(), 25);
try std.testing.expectEqual(int_queue.dequeue(), 50);
try std.testing.expectEqual(int_queue.dequeue(), 75);
try std.testing.expectEqual(int_queue.dequeue(), 100);
try std.testing.expectEqual(int_queue.dequeue(), null);
try int_queue.enqueue(5);
try std.testing.expectEqual(int_queue.dequeue(), 5);
try std.testing.expectEqual(int_queue.dequeue(), null);
}Shell$ zig test generic-type.zig
1/1 generic-type.test.queue...OK
All 1 tests passed.
在 Zig 中使用 cURL
curl.zig// compile with `zig build-exe zig-curl-test.zig --library curl --library c $(pkg-config --cflags libcurl)`
const std = @import("std");
const cURL = @cImport({
@cInclude("curl/curl.h");
});
pub fn main() !void {
var arena_state = std.heap.ArenaAllocator.init(std.heap.c_allocator);
defer arena_state.deinit();
const allocator = arena_state.allocator();
// global curl init, or fail
if (cURL.curl_global_init(cURL.CURL_GLOBAL_ALL) != cURL.CURLE_OK)
return error.CURLGlobalInitFailed;
defer cURL.curl_global_cleanup();
// curl easy handle init, or fail
const handle = cURL.curl_easy_init() orelse return error.CURLHandleInitFailed;
defer cURL.curl_easy_cleanup(handle);
var response_buffer = std.ArrayList(u8).init(allocator);
// superfluous when using an arena allocator, but
// important if the allocator implementation changes
defer response_buffer.deinit();
// setup curl options
if (cURL.curl_easy_setopt(handle, cURL.CURLOPT_URL, "https://ziglang.org") != cURL.CURLE_OK)
return error.CouldNotSetURL;
// set write function callbacks
if (cURL.curl_easy_setopt(handle, cURL.CURLOPT_WRITEFUNCTION, writeToArrayListCallback) != cURL.CURLE_OK)
return error.CouldNotSetWriteCallback;
if (cURL.curl_easy_setopt(handle, cURL.CURLOPT_WRITEDATA, &response_buffer) != cURL.CURLE_OK)
return error.CouldNotSetWriteCallback;
// perform
if (cURL.curl_easy_perform(handle) != cURL.CURLE_OK)
return error.FailedToPerformRequest;
std.log.info("Got response of {d} bytes", .{response_buffer.items.len});
std.debug.print("{s}\n", .{response_buffer.items});
}
fn writeToArrayListCallback(data: *anyopaque, size: c_uint, nmemb: c_uint, user_data: *anyopaque) callconv(.C) c_uint {
var buffer: *std.ArrayList(u8) = @alignCast(@ptrCast(user_data));
var typed_data: [*]u8 = @ptrCast(data);
buffer.appendSlice(typed_data[0 .. nmemb * size]) catch return 0;
return nmemb * size;
}