river: remove system /etc dir from init search paths

A true "default" config doesn't make sense for river. Everyone who uses
river seriously will customize their init script. Futhermore, the
current behavior of embedding the install path of the default system
config in the river binary is complex and prone to breaking.

README.md

@@ -10,11 +10,11 @@ and missing features. If you run into a bug don't hesitate to
 
 ## Design goals
 
-- Simplicity and minimalism, river should not overstep the bounds of a
-window manager.
+- Simple and predictable behavior, river should be easy to use and have a
+low cognitive load.
 - Window management based on a stack of views and tags.
-- Dynamic layouts generated by external, user-written executables. (A default
-`rivertile` layout generator is provided.)
+- Dynamic layouts generated by external, user-written executables. A default
+`rivertile` layout generator is provided.
 - Scriptable configuration and control through a custom wayland protocol and
 separate `riverctl` binary implementing it.
 
@@ -53,20 +53,18 @@ To enable experimental Xwayland support pass the `-Dxwayland` option as well.
 ## Usage
 
 River can either be run nested in an X11/wayland session or directly
-from a tty using KMS/DRM.
+from a tty using KMS/DRM. Simply run the `river` command.
 
-On startup river will look for and run an **executable** file at one of the
-following locations, checked in the order listed:
+On startup river will run an executable file at `$XDG_CONFIG_HOME/river/init`
+if such an executable exists. If $XDG_CONFIG_HOME is not set, ~/.config/ will
+be used instead.
 
-- `$XDG_CONFIG_HOME/river/init`
-- `$HOME/.config/river/init`
-- `/etc/river/init`
-
-Usually this executable init file will be a shell script invoking riverctl
-to create mappings and preform other configuration.
+Usually this executable is a shell script invoking *riverctl*(1) to create
+mappings, start programs such as a layout generator or status bar, and
+preform other configuration.
 
 An example init script with sane defaults is provided [here](example/init)
-in the example directory and installed to `/etc/river/init`.
+in the example directory.
 
 For complete documentation see the `river(1)`, `riverctl(1)`, and
 `rivertile(1)` man pages.

build.zig

@@ -48,14 +48,6 @@ pub fn build(b: *zbs.Builder) !void {
 
     const examples = b.option(bool, "examples", "Set to true to build examples") orelse false;
 
-    const rel_config_path = if (mem.eql(u8, try fs.path.resolve(b.allocator, &[_][]const u8{b.install_prefix}), "/usr"))
-        "../etc/river/init"
-    else
-        "etc/river/init";
-    b.installFile("example/init", rel_config_path);
-    const abs_config_path = try fs.path.resolve(b.allocator, &[_][]const u8{ b.install_prefix, rel_config_path });
-    assert(fs.path.isAbsolute(abs_config_path));
-
     const scanner = ScanProtocolsStep.create(b);
     scanner.addSystemProtocol("stable/xdg-shell/xdg-shell.xml");
     scanner.addSystemProtocol("unstable/pointer-gestures/pointer-gestures-unstable-v1.xml");
@@ -72,7 +64,6 @@ pub fn build(b: *zbs.Builder) !void {
         river.setTarget(target);
         river.setBuildMode(mode);
         river.addBuildOption(bool, "xwayland", xwayland);
-        river.addBuildOption([]const u8, "default_config_path", abs_config_path);
 
         addServerDeps(river, scanner);
 

doc/river.1.scd

@@ -32,19 +32,17 @@ utility may be used to communicate with river over these protocols.
 
 # CONFIGURATION
 
-On startup river will look for and run an executable file at one of the
-following locations, checked in the order listed:
-
-- $XDG_CONFIG_HOME/river/init
-- $HOME/.config/river/init
-- /etc/river/init
+On startup river will run an executable file at `$XDG_CONFIG_HOME/river/init`
+if such an executable exists. If $XDG_CONFIG_HOME is not set, ~/.config/ will
+be used instead.
 
 The executable init file will be run as a process group leader after river's
 wayland server is initialized but before entering the main loop. On exit,
 river will send SIGTERM to this process group.
 
-Usually this will be a shell script invoking *riverctl*(1) to create mappings,
-start programs such as a status bar, and preform other configuration.
+Usually this executable is a shell script invoking *riverctl*(1) to create
+mappings, start programs such as a layout generator or status bar, and
+preform other configuration.
 
 # ENVIRONMENT
 

river/main.zig

@@ -16,6 +16,7 @@
 // along with this program. If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
+const fs = std.fs;
 const os = std.os;
 const wlr = @import("wlroots");
 
@@ -86,9 +87,7 @@ pub fn main() anyerror!void {
         .warn, .err, .crit, .alert, .emerg => .err,
     });
 
-    if (startup_command == null) {
-        if (try getStartupCommand()) |path| startup_command = path;
-    }
+    if (startup_command == null) startup_command = try defaultInitPath();
 
     std.log.info("initializing server", .{});
     try server.init();
@@ -99,7 +98,7 @@ pub fn main() anyerror!void {
     // Run the child in a new process group so that we can send SIGTERM to all
     // descendants on exit.
     const child_pgid = if (startup_command) |cmd| blk: {
-        std.log.info("running startup command '{s}'", .{cmd});
+        std.log.info("running init executable '{s}'", .{cmd});
         const child_args = [_:null]?[*:0]const u8{ "/bin/sh", "-c", cmd, null };
         const pid = try os.fork();
         if (pid == 0) {
@@ -111,8 +110,9 @@ pub fn main() anyerror!void {
         // Since the child has called setsid, the pid is the pgid
         break :blk pid;
     } else null;
-    defer if (child_pgid) |pgid|
-        os.kill(-pgid, os.SIGTERM) catch |e| std.log.err("failed to kill startup process: {s}", .{e});
+    defer if (child_pgid) |pgid| os.kill(-pgid, os.SIGTERM) catch |err| {
+        std.log.err("failed to kill init process group: {s}", .{@errorName(err)});
+    };
 
     std.log.info("running server", .{});
 
@@ -127,30 +127,25 @@ fn printErrorExit(comptime format: []const u8, args: anytype) noreturn {
     os.exit(1);
 }
 
-fn testConfigPath(comptime fmt: []const u8, args: anytype) std.fmt.AllocPrintError!?[:0]const u8 {
-    const path = try std.fmt.allocPrintZ(util.gpa, fmt, args);
-    os.access(path, os.X_OK) catch {
+fn defaultInitPath() !?[:0]const u8 {
+    const path = blk: {
+        if (os.getenv("XDG_CONFIG_HOME")) |xdg_config_home| {
+            break :blk try fs.path.joinZ(util.gpa, &[_][]const u8{ xdg_config_home, "river/init" });
+        } else if (os.getenv("HOME")) |home| {
+            break :blk try fs.path.joinZ(util.gpa, &[_][]const u8{ home, ".config/river/init" });
+        } else {
+            return null;
+        }
+    };
+
+    os.accessZ(path, os.X_OK) catch |err| {
+        std.log.err("failed to run init executable {s}: {s}", .{ path, @errorName(err) });
         util.gpa.free(path);
         return null;
     };
-    return path;
-}
 
-fn getStartupCommand() std.fmt.AllocPrintError!?[:0]const u8 {
-    if (os.getenv("XDG_CONFIG_HOME")) |xdg_config_home| {
-        if (try testConfigPath("{s}/river/init", .{xdg_config_home})) |path| {
     return path;
 }
-    } else if (os.getenv("HOME")) |home| {
-        if (try testConfigPath("{s}/.config/river/init", .{home})) |path| {
-            return path;
-        }
-    }
-    if (try testConfigPath(build_options.default_config_path, .{})) |path| {
-        return path;
-    }
-    return null;
-}
 
 pub fn log(
     comptime message_level: std.log.Level,