main.zig

const std = @import("std");
const builtin = @import("builtin");
const testing = std.testing;
const process = std.process;
const fs = std.fs;
const ChildProcess = std.ChildProcess;

var a: *std.mem.Allocator = undefined;

pub fn main() !void {
    var arena = std.heap.ArenaAllocator.init(std.heap.page_allocator);
    defer arena.deinit();

    a = &arena.allocator;

    const stdout = std.io.getStdOut().writer();
    var build_args = std.ArrayList([]const u8).init(a);
    defer build_args.deinit();
    try build_args.appendSlice(&[_][]const u8{
        "/bin/ls",
        "-rtl",
        "/tmp",
    });
    const res = try exec("/tmp", build_args.items);
    try stdout.print("{s}\n", .{res.stdout});

    // const res = exec([]const []const u8 .{ "ls", "-l" }, "/tmp");
    // try stdout.print("------\n", .{});
}

fn printCmd(cwd: []const u8, argv: []const []const u8) void {
    std.debug.warn("cd {s} && ", .{cwd});
    for (argv) |arg| {
        std.debug.warn("{s} ", .{arg});
    }
    std.debug.warn("\n", .{});
}

fn exec(cwd: []const u8, argv: []const []const u8) !ChildProcess.ExecResult {
    const max_output_size = 100 * 1024 * 1024;
    // const result = ChildProcess.exec(a, argv, cwd, null, max_output_size) catch |err| {
    const result = ChildProcess.exec(.{
            .allocator = a,
            .argv = argv,
            .cwd = cwd,
            .env_map = null,
            .max_output_bytes = max_output_size,
        }) catch |err| {
        std.debug.warn("The following command failed:\n", .{});
        printCmd(cwd, argv);
        return err;
    };
    switch (result.term) {
        .Exited => |code| {
            if (code != 0) {
                std.debug.warn("The following command exited with error code {any}:\n", .{code});
                printCmd(cwd, argv);
                std.debug.warn("stderr:\n{s}\n", .{result.stderr});
                return error.CommandFailed;
            }
        },
        else => {
            std.debug.warn("The following command terminated unexpectedly:\n", .{});
            printCmd(cwd, argv);
            std.debug.warn("stderr:\n{s}\n", .{result.stderr});
            return error.CommandFailed;
        },
    }
    return result;
}