diff --git a/.gitignore b/.gitignore index 4c82b07..f8e519f 100644 --- a/.gitignore +++ b/.gitignore @@ -1,2 +1,3 @@ zig-cache zig-out +core diff --git a/src/main.zig b/src/main.zig index 56a3184..506ec57 100644 --- a/src/main.zig +++ b/src/main.zig @@ -352,16 +352,55 @@ fn installSignalHandler() !void { } pub fn main() !void { + // We are linked to libc, and primarily using the arena allocator + // raw allocator recommended for use in arenas + var raw_allocator = std.heap.raw_c_allocator; + + // Our child process will also need an allocator, and is using the + // same pattern, so we will hand the child a raw allocator as well + var child_allocator = std.heap.raw_c_allocator; + + // Lastly, we need some of our own operations + var arena = std.heap.ArenaAllocator.init(raw_allocator); + defer arena.deinit(); + var parent_allocator = arena.allocator(); + + var al = std.ArrayList([]const u8).init(parent_allocator); + defer al.deinit(); + var argi = std.process.args(); + // We do this first so it shows more prominently when looking at processes + // Also it will be slightly faster for whatever that is worth + const child_arg = "--child"; + if (argi.next()) |a| try al.append(a); + try al.append(child_arg); + while (argi.next()) |a| { + if (std.mem.eql(u8, child_arg, a)) { + // This should never actually return + return try childMain(child_allocator); + } + try al.append(a); + } + // Parent + const stdin = std.io.getStdIn(); + const stdout = std.io.getStdOut(); + const stderr = std.io.getStdErr(); + while (true) { + // If we use the arena here, we risk a memory leak when our child + // panics. This is because arenas don't actually free memory until + // they deinit. So we need to use the raw allocator here, but the + // arena can be used to store our arguments above + var cp = std.ChildProcess.init(al.items, raw_allocator); + cp.stdin = stdin; + cp.stdout = stdout; + cp.stderr = stderr; + _ = try cp.spawnAndWait(); + try stderr.writeAll("Caught abnormal process termination, relaunching server"); + } +} + +fn childMain(allocator: std.mem.Allocator) !void { defer exitApp(1); - // stdout is for the actual output of your application, for example if you - // are implementing gzip, then only the compressed bytes should be sent to - // stdout, not any debugging messages. - // const stdout_file = std.io.getStdOut().writer(); - // var bw = std.io.bufferedWriter(stdout_file); - // const stdout = bw.writer(); - - var allocator = std.heap.raw_c_allocator; // raw allocator recommended for use in arenas executors = try loadConfig(allocator); defer allocator.free(executors); defer parsed_config.deinit();