Update 3:
But if I try to do anything inside the function if will segfault, this for example result in a Segmentation fault at address 0x0
pub export fn gameInit() void {
std.debug.print("Init done", .{});
}
Update 2:
Looks to have to do with the return of gameInit, if I make it return void it works, however I would need it to not be void.
var gameInit: *const fn () void = undefined;
Update:
Code is now avaliable at Stuck with error · favetelinguis/ztuig@f5ba3fa · GitHub
I am currently playing around with Zig and hot code where I get an error I do not understand at all. Given the following code.
main.zig
const std = @import("std");
const debug = std.debug;
const game_lib = @import("game.zig");
const gameInit_t = @TypeOf(game_lib.gameInit);
var gameInit: *gameInit_t = undefined;
pub fn main() !void {
var gpa = std.heap.GeneralPurposeAllocator(.{}){};
const allocator = gpa.allocator();
loadGameDll() catch @panic("Failed to load game.so");
_ = gameInit();
var count: u32 = 1;
while (true) {
if (count % 5 == 0) { // reload every 5 seconds
unloadGameDll() catch unreachable;
recompileGameDll(allocator) catch {
std.debug.print("Failed to recompile game.dll\n", .{});
};
loadGameDll() catch @panic("Failed to load game.dll");
}
std.time.sleep(1_000_000_000);
count += 1;
}
}
var game_dyn_lib: ?std.DynLib = null;
fn loadGameDll() !void {
if (game_dyn_lib != null) return error.AlreadyLoaded;
var dyn_lib = std.DynLib.open("zig-out/lib/libgame.so") catch {
return error.OpenFail;
};
game_dyn_lib = dyn_lib;
gameInit = dyn_lib.lookup(*gameInit_t, "gameInit") orelse return error.LookupFail;
std.debug.print("Loaded libgame.so\n", .{});
}
fn unloadGameDll() !void {
if (game_dyn_lib) |*dyn_lib| {
dyn_lib.close();
game_dyn_lib = null;
} else {
return error.AlreadyUnloaded;
}
}
fn recompileGameDll(allocator: std.mem.Allocator) !void {
const process_args = [_][]const u8{
"zig",
"build",
"-Dgame_only=true",
};
var build_process = std.process.Child.init(&process_args, allocator);
try build_process.spawn();
const term = try build_process.wait();
switch (term) {
.Exited => |exited| {
if (exited == 2) return error.RecompileFail;
},
else => return,
}
}
game.zig
const std = @import("std");
pub const GameState = struct {};
pub export fn gameInit() *GameState {
var gpa = std.heap.GeneralPurposeAllocator(.{}){};
const allocator = gpa.allocator();
return allocator.create(GameState) catch @panic("out of memory");
}
I get the following error when trying to run it. It looks like it loads the dynamic lib ok but then fail to run gameInit(). Any ideas on how to make progress on fixing the issue and understanding the root of the error.
$ zig build run2 -Dgame_only=false
Loaded libgame.so
General protection exception (no address available)
???:?:?: 0x7f7e21bddd90 in ??? (???)
Unwind information for `???:0x7f7e21bddd90` was not available, trace may be incomplete
/home/h/repos/zigs/ztuig/src/main2.zig:23:17: 0x103c0f1 in main (hotr)
_ = gameInit();
^
/nix/store/j9sp79vdhz4l6lfnvzhvcprhar803zr3-zig-0.13.0/lib/zig/std/start.zig:524:37: 0x103ae14 in posixCallMainAndExit (hotr)
const result = root.main() catch |err| {
^
/nix/store/j9sp79vdhz4l6lfnvzhvcprhar803zr3-zig-0.13.0/lib/zig/std/start.zig:266:5: 0x103a951 in _start (hotr)
asm volatile (switch (native_arch) {
^
run2
└─ run hotr failure
error: the following command terminated unexpectedly:
/home/h/repos/zigs/ztuig/zig-out/bin/hotr
Build Summary: 7/9 steps succeeded; 1 failed (disable with --summary none)
run2 transitive failure
└─ run hotr failure
error: the following build command failed with exit code 1:
/home/h/repos/zigs/ztuig/.zig-cache/o/b99ecefa070148799c71cbf52f917711/build /nix/store/j9sp79vdhz4l6lfnvzhvcprhar803zr3-zig-0.13.0/bin/zig /home/h/repos/zigs/ztuig /home/h/repos/zigs/ztuig/.zig-cache /home/h/.cache/zig --seed 0x7f4b92cb -Z4de9b50e3d3bb79a run2 -Dgame_only=false
error: Recipe `rerun` failed on line 2 with exit code 1
The code is very much taken from hotreload/src/main.zig at master · samhattangady/hotreload · GitHub
and
Hot-reloading with Raylib - Zig NEWS
