feat: unify system status codes

programs/include/Api/Syscall.hpp

@@ -7,6 +7,7 @@
 #pragma once
 #include <cstdint>
 #include <cstddef>
+#include <montauk/statuscodes.h>
 
 namespace montauk::abi {
 
@@ -312,6 +313,9 @@ namespace montauk::abi {
     static_assert((CAP_ADMIN_SESSION & CAP_COMPOSITOR) == 0,
                   "a session must not delegate the compositor's authority; "
                   "login grants it to the desktop directly");
+    // Capability denial for the Wi-Fi and USB syscalls only, which keep their
+    // own WIFI_ERR_* / USB_ERR_* spaces; everything else returns
+    // CapabilityDenied from StatusCodes.
     static constexpr int SYS_ERR_PERMISSION = -13;
 
     // A process holds two independent sets: what it may use (effective) and

programs/include/libc/montauk.h

@@ -219,6 +219,27 @@ extern "C" {
 #define MTK_SYS_CONSENT_REPLY      193
 /* @SYSCALLS-END */
 
+/* Syscall status codes (montauk/statuscodes.h for C++). */
+/* @STATUS-BEGIN
+   Generated from Common/StatusCodes.hpp by scripts/montauk-syscalls.py.
+   Do not edit by hand; run 'make gen-syscalls' to refresh. */
+#define MTK_STATUS_SUCCESS                (0)
+#define MTK_STATUS_GENERIC_FAILURE        (-1)
+#define MTK_STATUS_PERMISSION_DENIED      (-2)
+#define MTK_STATUS_CAPABILITY_DENIED      (-3)
+#define MTK_STATUS_SYSTEM_INTEGRITY_ERROR (-4)
+#define MTK_STATUS_BAD_POINTER            (-5)
+#define MTK_STATUS_INVALID_ARGUMENT       (-6)
+#define MTK_STATUS_UNSUPPORTED_OP         (-7)
+#define MTK_STATUS_NO_DEVICE              (-8)
+#define MTK_STATUS_IO_FAILURE             (-9)
+#define MTK_STATUS_BAD_INVOCATION         (-10)
+#define MTK_STATUS_NO_SUCH_PATH           (-11)
+#define MTK_STATUS_BUSY                   (-12)
+#define MTK_STATUS_BUFFER_TOO_SMALL       (-13)
+#define MTK_STATUS_OUT_OF_MEMORY          (-14)
+/* @STATUS-END */
+
 #define MTK_SOCK_TCP 1
 #define MTK_SOCK_UDP 2
 #define MTK_IPC_SIGNAL_READABLE    (1u << 0)

programs/include/montauk/statuscodes.h

@@ -0,0 +1,35 @@
+/*
+    * statuscodes.h
+    * MontaukOS status codes
+    * Copyright (c) 2026 Daniel Hammer
+*/
+
+#pragma once
+
+// Userspace mirror of kernel/src/Common/StatusCodes.hpp. Also usable from C
+// (the libc includes it), where the enumerators are unqualified.
+#ifdef __cplusplus
+namespace montauk {
+#endif
+
+enum StatusCodes {
+    Success = 0,
+    GenericFailure = -1,
+    PermissionDenied = -2,
+    CapabilityDenied = -3,
+    SystemIntegrityError = -4,
+    BadPointer = -5,
+    InvalidArgument = -6,
+    UnsupportedOp = -7,
+    NoDevice = -8,
+    IoFailure = -9,
+    BadInvocation = -10,
+    NoSuchPath = -11,
+    Busy = -12,
+    BufferTooSmall = -13,
+    OutOfMemory = -14
+};
+
+#ifdef __cplusplus
+}
+#endif

programs/include/montauk/syscall.h

@@ -6,6 +6,7 @@
 
 #pragma once
 #include <Api/Syscall.hpp>
+#include <montauk/statuscodes.h>
 
 namespace montauk {
 

programs/lib/libc/libc.c

@@ -15,6 +15,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <fcntl.h>
+#include "../../include/montauk/statuscodes.h"
 #include <math.h>
 #include <string.h>
 #include <time.h>
@@ -2476,7 +2477,7 @@ char *getcwd(char *buf, size_t size) {
     }
     int result = (int)_mtk_syscall2(SYS_GETCWD, (long)buf, (long)size);
     if (result < 0) {
-        errno = result == -2 ? ERANGE : EIO;
+        errno = result == BufferTooSmall ? ERANGE : EIO;
         return NULL;
     }
     return buf;
@@ -3566,9 +3567,10 @@ int utime(const char *path, const struct utimbuf *times) {
                                 times != NULL ? (long)times->modtime : 0,
                                 times == NULL);
     if (result == 0) return 0;
-    if (result == -2) errno = ENOTSUP;
-    else if (result == -3) errno = EOVERFLOW;
-    else if (result == -4) errno = EIO;
+    if (result == UnsupportedOp) errno = ENOTSUP;
+    else if (result == InvalidArgument) errno = EOVERFLOW;
+    else if (result == IoFailure) errno = EIO;
+    else if (result == SystemIntegrityError) errno = EPERM;
     else errno = ENOENT;
     return -1;
 }

programs/src/display/main.cpp

@@ -500,7 +500,7 @@ static void apply_changes() {
     if (g_driver_available && g_selected_mode != g_info.currentMode) {
         int result = montauk::display_set_mode(g_selected_mode);
         if (result < 0) {
-            set_status(result == -2
+            set_status(result == montauk::UnsupportedOp
                 ? "Mode needs unsupported display-link training"
                 : "Mode change failed; previous mode restored");
             refresh_state(true);

programs/src/login/login_shutdown.cpp

@@ -262,7 +262,7 @@ void perform_graceful_shutdown(LoginState* ls, int action) {
     // A successful power-control syscall never returns.  If it does return,
     // keep the trusted supervisor alive and make the authorization failure
     // visible instead of falling through an unreachable-code assumption.
-    show_stage(ls, heading, rc == montauk::abi::SYS_ERR_PERMISSION
+    show_stage(ls, heading, rc == montauk::CapabilityDenied
         ? "Power control permission denied."
         : "Power control failed.");
     for (;;) montauk::sleep_ms(1000);

programs/src/reset/main.cpp

@@ -9,7 +9,7 @@
 extern "C" void _start() {
     montauk::print("Rebooting...\n");
     int rc = montauk::reset();
-    if (rc == montauk::abi::SYS_ERR_PERMISSION)
+    if (rc == montauk::CapabilityDenied)
         montauk::print("reset: permission denied\n");
     else
         montauk::print("reset: reboot failed\n");

programs/src/shell/main.cpp

@@ -194,7 +194,7 @@ static int process_command(const char* line) {
             : montauk::abi::POWER_REQ_SHUTDOWN;
         int rc = montauk::power_request(action);
         if (rc == 0) montauk::exit(0);
-        montauk::print(rc == montauk::abi::SYS_ERR_PERMISSION
+        montauk::print(rc == montauk::CapabilityDenied
             ? "power: permission denied\n"
             : "power: request failed\n");
         return 1;
@@ -202,7 +202,7 @@ static int process_command(const char* line) {
 
     if (streq(cmd, "suspend")) {
         int rc = montauk::suspend();
-        if (rc == montauk::abi::SYS_ERR_PERMISSION)
+        if (rc == montauk::CapabilityDenied)
             montauk::print("suspend: permission denied\n");
         return rc == 0 ? 0 : 1;
     }