Support viewing logs (a bit)

It does not fully work yet, but it's pretty interesting.  :)

zig/sdl/hello_sdl.zig

@@ -19,7 +19,6 @@ const std = @import("std");
// commands wishlist:
// - search (e.g. default current dir + /usr/include)
// - launch with logs (default launcher, use systemd-run --user --unit=name name?)
// - view (the above logs)
// - switch to window
// - open url
// - open shortcuts (logs -> ..., tickets)
@@ -219,7 +218,7 @@ const RegexRunner = struct {
    }
};
var cmd_buf: [100]u8 = undefined;
var cmd_buf: [1000]u8 = undefined;
const GoDocRunner = struct {
    fn init() RegexRunner {
@@ -312,6 +311,26 @@ const SearchRunner = struct {
    }
};
const LogsRunner = struct {
    fn init() RegexRunner {
        return RegexRunner{ .name = "logs", .run_always = true, .toArgv = toArgv, .isActive = isActive };
    }
    fn isActive(cmd: []const u8) bool {
        return std.mem.startsWith(u8, cmd, "logs");
    }
    fn toArgv(cmd: []const u8) []const []const u8 {
        if (cmd.len <= "logs ".len) {
            return &[_][]const u8{ "journalctl", "-b" };
        }
        const service = cmd["logs ".len..];
        _ = std.fmt.bufPrint(&cmd_buf, "(systemctl status {s} &> /dev/null && journalctl -u {s} -f) || (systemctl status --user {s} &> /dev/null && journalctl --user -u {s} -f) || echo \"no logs for '{s}'\"", .{ service, service, service, service, service }) catch "???";
        return &[_][]const u8{ "bash", "-c", &cmd_buf };
    }
};
const QalcRunner = struct {
    fn init() RegexRunner {
        return RegexRunner{ .name = "qalc", .run_always = true, .toArgv = toArgv, .isActive = isActive };
@@ -399,6 +418,7 @@ pub fn main() !void {
        HelpRunner.init(),
        ManPageRunner.init(),
        SearchRunner.init(),
        LogsRunner.init(),
        QalcRunner.init(),
    };