river/river/command/spawn.zig
Isaac Freund f80992e329
meta: make copyright headers more maintainable
- list all files as copyright "The River Developers"
- add an AUTHORS file to acknowledge contributors
2020-11-11 20:33:43 +01:00

66 lines
2.2 KiB
Zig

// This file is part of river, a dynamic tiling wayland compositor.
//
// Copyright 2020 The River Developers
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>.
const std = @import("std");
const c = @import("../c.zig");
const Error = @import("../command.zig").Error;
const Seat = @import("../Seat.zig");
/// Spawn a program.
pub fn spawn(
allocator: *std.mem.Allocator,
seat: *Seat,
args: []const []const u8,
out: *?[]const u8,
) Error!void {
if (args.len < 2) return Error.NotEnoughArguments;
const cmd = try std.mem.join(allocator, " ", args[1..]);
defer allocator.free(cmd);
const cmdZ = try std.cstr.addNullByte(allocator, cmd);
defer allocator.free(cmdZ);
const child_args = [_:null]?[*:0]const u8{ "/bin/sh", "-c", cmdZ, null };
const pid = std.os.fork() catch {
out.* = try std.fmt.allocPrint(allocator, "fork/execve failed", .{});
return Error.Other;
};
if (pid == 0) {
// Clean things up for the child in an intermediate fork
if (c.setsid() < 0) unreachable;
if (std.os.system.sigprocmask(std.os.SIG_SETMASK, &std.os.empty_sigset, null) < 0) unreachable;
const pid2 = std.os.fork() catch c._exit(1);
if (pid2 == 0) std.os.execveZ("/bin/sh", &child_args, std.c.environ) catch c._exit(1);
c._exit(0);
}
// Wait the intermediate child.
const ret = std.os.waitpid(pid, 0);
if (!std.os.WIFEXITED(ret.status) or
(std.os.WIFEXITED(ret.status) and std.os.WEXITSTATUS(ret.status) != 0))
{
out.* = try std.fmt.allocPrint(allocator, "fork/execve failed", .{});
return Error.Other;
}
}