add timeout (#34)

Author: jiacai2050

build.zig

@@ -124,6 +124,7 @@ fn buildBinaries(
         "dark-mode",
         "repeat",
         "tcp-proxy",
+        "timeout",
     }) |name| {
         try buildBinary(
             b,
@@ -207,7 +208,7 @@ fn makeCompileStep(
     // We can't use `target.result.isDarwin()` here
     // Since when cross compile to darwin, there is no framework in the host!
     const is_darwin = @import("builtin").os.tag == .macos;
-
+    const is_win = target.result.os.tag == .windows;
     if (!is_darwin) {
         if (std.mem.eql(u8, name, "night-shift") or std.mem.eql(u8, name, "dark-mode")) {
             return null;
@@ -229,6 +230,11 @@ fn makeCompileStep(
         exe.linkFramework("SkyLight");
     } else if (std.mem.eql(u8, name, "tcp-proxy")) {
         exe.linkLibC();
+    } else if (std.mem.eql(u8, name, "timeout")) {
+        if (is_win) { // error: TODO windows Sigaction definition
+            return null;
+        }
+        exe.linkLibC();
     } else if (std.mem.eql(u8, name, "zigfetch")) {
         if (skip_zigfetch) {
             return null;

docs/content/programs/timeout.org

@@ -0,0 +1,18 @@
+#+TITLE: timeout
+#+DATE: 2025-01-23T22:28:53+0800
+#+LASTMOD: 2025-01-23T22:35:32+0800
+#+TYPE: docs
+#+DESCRIPTION: Run a command with bounded time
+
+#+begin_example
+timeout SECONDS COMMAND [ARG]...
+#+end_example
+
+Start a command, and kill it if the specified timeout expires.
+
+The =timeout= command is crucial for:
+
+- Process Control
+- Limits execution time of commands
+- Prevents resource-consuming tasks from running indefinitely
+- Provides automatic process termination

docs/content/programs/zigfetch.org

@@ -1,12 +1,12 @@
 #+TITLE: zigfetch
 #+DATE: 2025-01-01T18:01:47+0800
-#+LASTMOD: 2025-01-04T09:46:39+0800
+#+LASTMOD: 2025-01-04T17:16:15+0800
 #+TYPE: docs
 #+DESCRIPTION: Fetch zig packages, utilizing libcurl.
 
-=zigfetch= behaves similarly to =zig fetch=, utilizing the capabilities of libcurl for its functionality.
+=zigfetch= behaves similarly to =zig fetch=, but utilizing the capabilities of libcurl for its functionality.
 
-Since the HTTP support within Zig's standard library isn't currently stable, [[https://github.com/ziglang/zig/issues/21792][this  proxy issue]] make it even harder, resulting in multiple errors occurring during dependency downloads when building Zig projects.
+HTTP support within Zig's standard library isn't currently stable, [[https://github.com/ziglang/zig/issues/21792][this  proxy issue]] make it even harder, resulting in multiple errors occurring during dependency downloads when building Zig projects.
 
 {{< figure src="https://fs.liujiacai.net/cdn-img/zigcli/zig-fetch-errors.webp" >}}
 

src/bin/timeout.zig

@@ -0,0 +1,66 @@
+//! Run a command with bounded time
+//! https://github.com/coreutils/coreutils/blob/v9.6/src/timeout.c
+
+const std = @import("std");
+const posix = std.posix;
+const Child = std.process.Child;
+
+pub var child: Child = undefined;
+pub var spawn_success = false;
+
+pub fn main() !void {
+    try posix.sigaction(posix.SIG.ALRM, &posix.Sigaction{
+        .handler = .{
+            .handler = struct {
+                pub fn handler(got: c_int) callconv(.C) void {
+                    std.debug.assert(got == posix.SIG.ALRM);
+                    _ = child.kill() catch |e| {
+                        std.log.err("Kill child failed, err:{any}", .{e});
+                        return;
+                    };
+                    posix.exit(124); // timeout
+                }
+            }.handler,
+        },
+        .mask = posix.empty_sigset,
+        .flags = 0,
+    }, null);
+
+    var gpa = std.heap.GeneralPurposeAllocator(.{}){};
+    defer if (gpa.deinit() != .ok) @panic("leak");
+    const allocator = gpa.allocator();
+
+    const args = try std.process.argsAlloc(allocator);
+    defer std.process.argsFree(allocator, args);
+
+    if (args.len < 3) {
+        std.debug.print(
+            \\Usage:
+            \\ {s} SECONDS COMMAND [ARG]...
+            \\
+        , .{args[0]});
+        posix.exit(1);
+    }
+
+    const ttl_seconds = try std.fmt.parseInt(c_uint, args[1], 10);
+    const cmds = args[2..];
+    const ret = std.c.alarm(ttl_seconds);
+    if (ret != 0) {
+        std.log.err("Set alarm signal failed, retcode:{d}", .{ret});
+        posix.exit(1);
+    }
+
+    child = Child.init(cmds, allocator);
+    try child.spawn();
+    spawn_success = true;
+    const term = try child.wait();
+    switch (term) {
+        .Exited => |status| {
+            posix.exit(status);
+        },
+        else => {
+            std.log.err("Child internal error, term:{any}", .{term});
+            posix.exit(125);
+        },
+    }
+}

src/bin/zigfetch.zig

@@ -365,15 +365,15 @@ fn moveToCache(allocator: Allocator, src_dir: []const u8, hex: Manifest.MultiHas
     const dst = try std.fmt.allocPrint(allocator, "{s}/p/{s}", .{ cache_dirname, hex });
     defer allocator.free(dst);
 
-    _ = fs.openDirAbsolute(dst, .{}) catch |err| switch (err) {
-        error.FileNotFound => {
-            return fs.renameAbsolute(src_dir, dst);
-        },
-        else => return err,
-    };
-    if (args.verbose) {
-        log.info("Dir({s}) already exists, skip copy...", .{dst});
+    const found = try checkFileExists(dst);
+    if (found) {
+        if (args.verbose) {
+            log.info("Dir({s}) already exists, skip copy...", .{dst});
+        }
+        return;
     }
+
+    try fs.renameAbsolute(src_dir, dst);
 }
 
 fn fetchPackage(allocator: Allocator, url: [:0]const u8, out_dir: fs.Dir) ![]const u8 {
@@ -921,3 +921,13 @@ fn recursiveDirectoryCopy(allocator: Allocator, dir: fs.Dir, tmp_dir: fs.Dir) an
         }
     }
 }
+
+// Returns true if path exists
+fn checkFileExists(path: []const u8) !bool {
+    fs.cwd().access(path, .{}) catch |e| switch (e) {
+        error.FileNotFound => return false,
+        else => return e,
+    };
+
+    return true;
+}