lib: General Linux RISC-V64 syscall support.

* include/linux/riscv32/kernel-stat.h,
include/linux/riscv64/kernel-stat.h: New files.
* include/fcntl.h (AT_FDCWD, AT_SYMLINK_NOFOLLOW, AT_REMOVEDIR): Add
necessary constants.
* include/stdint.h: Integer size defines for RISC-V.
* include/sys/stat.h: "stat" struct for RISC-V.
* lib/linux/_open3.c (_open3)[!SYS_open]: Use SYS_openat.
* lib/linux/access.c (access)[!SYS_access]: Use SYS_faccessat.
* lib/linux/chmod.c (chmod)[!SYS_chmod]: Use SYS_fchmodat.
* lib/linux/dup2.c (dup2)[!SYS_dup2]: Use if SYS_dup3.
* lib/linux/fork.c (fork)[!SYS_fork]: Use SYS_clone.
* lib/linux/getdents.c (getdents)[!SYS_getdents]: Use SYS_getdents64.
* lib/linux/link.c (link)[!SYS_link]: Use SYS_linkat.
* lib/linux/lstat.c (lstat)[!SYS_lstat]: Use SYS_newfstatat.
* lib/linux/mkdir.c (mkdir)[!SYS_mkdir]: Use SYS_mkdirat.
* lib/linux/mknod.c (mknod)[!SYS_mknod]: Use SYS_mknodat.
* lib/linux/pipe.c (pipe)[!SYS_pipe]: Use SYS_pipe2.
* lib/linux/readlink.c (readlink)[!SYS_readlinkat]: Use SYS_readlinkat.
* lib/linux/rename.c (rename)[!SYS_rename]: Use SYS_renameat2.
* lib/linux/rmdir.c (rmdir)[!SYS_rmdir]: Use SYS_unlinkat.
* lib/linux/signal.c (_restorer_for_siginfo): Remove unused function
that causes compilation issue.
* lib/linux/stat.c (stat)[!SYS_stat]: Use SYS_newfstatat.
* lib/linux/symlink.c (symlink)[!SYS_symlinkat]: Use SYS_symlink.
* lib/linux/unlink.c (unlink)[!SYS_unlink]: Use SYS_unlinkat.

include/fcntl.h

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2017 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  * Copyright © 2023 Emily Trau <emily@downunderctf.com>
  *
  * This file is part of GNU Mes.
@@ -48,6 +49,10 @@
 #define O_TMPFILE   0x410000
 #endif
 
+#define AT_FDCWD            -100
+#define AT_SYMLINK_NOFOLLOW  0x100
+#define AT_REMOVEDIR         0x200
+
 #elif __GNU__
 #define	O_RDONLY	  1
 #define	O_WRONLY	  2

include/linux/riscv32/kernel-stat.h

@@ -0,0 +1,46 @@
+/* -*-comment-start: "//";comment-end:""-*-
+ * GNU Mes --- Maxwell Equations of Software
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
+ *
+ * This file is part of GNU Mes.
+ *
+ * GNU Mes 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.
+ *
+ * GNU Mes 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 GNU Mes.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __MES_LINUX_RISCV32_KERNEL_STAT_H
+#define __MES_LINUX_RISCV32_KERNEL_STAT_H 1
+
+// *INDENT-OFF*
+struct stat
+{
+  unsigned long  st_dev;
+  unsigned long  st_ino;
+  unsigned short st_mode;
+  unsigned short st_nlink;
+  unsigned short st_uid;
+  unsigned short st_gid;
+  unsigned long  st_rdev;
+  long           st_size; /* Linux: unsigned long; glibc: off_t (i.e. signed) */
+  unsigned long  st_blksize;
+  unsigned long  st_blocks;
+  time_t         st_atime; /* Linux: unsigned long; glibc: time_t */
+  unsigned long  st_atime_usec;
+  time_t         st_mtime; /* Linux: unsigned long; glibc: time_t */
+  unsigned long  st_mtime_usec;
+  time_t         st_ctime; /* Linux: unsigned long; glibc: time_t */
+  unsigned long  st_ctime_usec;
+  unsigned long  __foo0;
+  unsigned long  __foo1;
+};
+
+#endif // __MES_LINUX_RISCV32_KERNEL_STAT_H

include/linux/riscv64/kernel-stat.h

@@ -0,0 +1,46 @@
+/* -*-comment-start: "//";comment-end:""-*-
+ * GNU Mes --- Maxwell Equations of Software
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
+ *
+ * This file is part of GNU Mes.
+ *
+ * GNU Mes 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.
+ *
+ * GNU Mes 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 GNU Mes.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __MES_LINUX_RISCV64_KERNEL_STAT_H
+#define __MES_LINUX_RISCV64_KERNEL_STAT_H 1
+
+// *INDENT-OFF*
+struct stat
+{
+  unsigned long  st_dev;
+  unsigned long  st_ino;
+  unsigned int   st_mode;
+  unsigned int   st_nlink;
+  unsigned int   st_uid;
+  unsigned int   st_gid;
+  unsigned long  st_rdev;
+  long           st_size;
+  unsigned long  st_blksize;
+  unsigned long  st_blocks;
+  time_t         st_atime;
+  unsigned long  st_atime_usec;
+  time_t         st_mtime;
+  unsigned long  st_mtime_usec;
+  time_t         st_ctime;
+  unsigned long  st_ctime_usec;
+  unsigned long  __foo0;
+  unsigned long  __foo1;
+};
+
+#endif // __MES_LINUX_RISCV64_KERNEL_STAT_H

include/stdint.h

@@ -87,7 +87,7 @@ typedef unsigned uintmax_t;
 
 #define INT_MIN -2147483648
 #define INT_MAX 2147483647
-#if __i386__ || __arm__
+#if __i386__ || __arm__ || __riscv_xlen == 32
 #define LONG_MIN INT_MIN
 #define LONG_MAX INT_MAX
 #define UINT_MAX UINT32_MAX
@@ -95,7 +95,7 @@ typedef unsigned uintmax_t;
 #define LLONG_MIN INT64_MIN
 #define LLONG_MAX INT64_MAX
 #define SIZE_MAX UINT32_MAX
-#elif __x86_64__
+#elif __x86_64__ || __riscv_xlen == 64
 #define LONG_MIN INT64_MIN
 #define LONG_MAX INT64_MAX
 #define UINT_MAX UINT32_MAX

lib/linux/_open3.c

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2016,2017,2018,2019,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -27,7 +28,13 @@ int
 _open3 (char const *file_name, int flags, int mask)
 {
   long long_file_name = cast_charp_to_long (file_name);
+#if defined (SYS_open)
   int r = _sys_call3 (SYS_open, long_file_name, flags, mask);
+#elif defined (SYS_openat)
+  int r = _sys_call4 (SYS_openat, AT_FDCWD, long_file_name, flags, mask);
+#else
+#error No usable open syscall
+#endif
   __ungetc_init ();
   if (r > 2)
     {

lib/linux/access.c

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2016,2017,2018,2019,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -21,11 +22,18 @@
 #include <mes/lib.h>
 #include <linux/syscall.h>
 #include <arch/syscall.h>
+#include <fcntl.h>
 
 int
 access (char const *file_name, int how)
 {
   long long_file_name = cast_charp_to_long (file_name);
   long long_how = cast_int_to_long (how);
+#if defined (SYS_access)
   return _sys_call2 (SYS_access, long_file_name, long_how);
+#elif defined (SYS_faccessat)
+  return _sys_call3 (SYS_faccessat, AT_FDCWD, long_file_name, long_how);
+#else
+#error No usable access sysall
+#endif
 }

lib/linux/chmod.c

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2016,2017,2018,2019,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -22,11 +23,18 @@
 #include <linux/syscall.h>
 #include <arch/syscall.h>
 #include <sys/stat.h>
+#include <fcntl.h>
 
 int
 chmod (char const *file_name, mode_t mask)
 {
   long long_file_name = cast_charp_to_long (file_name);
   long long_mask = cast_int_to_long (mask);
+#if defined (SYS_chmod)
   return _sys_call2 (SYS_chmod, long_file_name, long_mask);
+#elif defined (SYS_fchmodat)
+  return _sys_call3 (SYS_fchmodat, AT_FDCWD, long_file_name, long_mask);
+#else
+#error No usable chmod syscall
+#endif
 }

lib/linux/dup2.c

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2016,2017,2018,2019,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -26,5 +27,11 @@ dup2 (int old, int new)
 {
   long long_old = old;
   long long_new = new;
+#if defined (SYS_dup2)
   return _sys_call2 (SYS_dup2, long_old, long_new);
+#elif defined (SYS_dup3)
+  return _sys_call3 (SYS_dup3, long_old, long_new, 0);
+#else
+#error No usable dup2 syscall
+#endif
 }

lib/linux/fork.c

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2016,2017,2018,2019,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -20,9 +21,17 @@
 
 #include <linux/syscall.h>
 #include <arch/syscall.h>
+#include <signal.h>
+#include <unistd.h>
 
 int
 fork ()
 {
+#if defined (SYS_fork)
   return _sys_call (SYS_fork);
+#elif defined (SYS_clone)
+  return _sys_call4 (SYS_clone, SIGCHLD, 0, NULL, 0);
+#else
+#error No usable clone syscall found
+#endif
 }

lib/linux/getdents.c

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2018,2019,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -25,5 +26,11 @@
 int
 getdents (int filedes, char *buffer, size_t nbytes)
 {
+#if defined (SYS_getdents)
   return _sys_call3 (SYS_getdents, (int) filedes, (long) buffer, (long) nbytes);
+#elif defined (SYS_getdents64)
+  return _sys_call3 (SYS_getdents64, (int) filedes, (long) buffer, (long) nbytes);
+#else
+#error No usable getdents syscall
+#endif
 }

lib/linux/link.c

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2018,2019,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -20,9 +21,16 @@
 
 #include <linux/syscall.h>
 #include <arch/syscall.h>
+#include <fcntl.h>
 
 int
 link (char const *old_name, char const *new_name)
 {
+#if defined (SYS_link)
   return _sys_call2 (SYS_link, (long) old_name, (long) new_name);
+#elif defined (SYS_linkat)
+  return _sys_call4 (SYS_linkat, AT_FDCWD, (long) old_name, AT_FDCWD, (long) new_name);
+#else
+#error No usable link syscall
+#endif
 }

lib/linux/lstat.c

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2018,2019,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -20,10 +21,18 @@
 
 #include <linux/syscall.h>
 #include <arch/syscall.h>
+#include <fcntl.h>
 #include <sys/stat.h>
 
 int
 lstat (char const *file_name, struct stat *statbuf)
 {
+#if defined (SYS_lstat)
   return _sys_call2 (SYS_lstat, (long) file_name, (long) statbuf);
+#elif defined (SYS_newfstatat)
+  return _sys_call4 (SYS_newfstatat, AT_FDCWD, (long) file_name, (long) statbuf, 0);
+#else
+#error No usable stat syscall
+#endif
+  return 0;
 }

lib/linux/mkdir.c

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2018,2019,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -20,10 +21,17 @@
 
 #include <linux/syscall.h>
 #include <arch/syscall.h>
+#include <fcntl.h>
 #include <sys/stat.h>
 
 int
 mkdir (char const *file_name, mode_t mode)
 {
+#if defined (SYS_mkdir)
   return _sys_call2 (SYS_mkdir, (long) file_name, (long) mode);
+#elif defined (SYS_mkdirat)
+  return _sys_call3 (SYS_mkdirat, AT_FDCWD, (long) file_name, (long) mode);
+#else
+#error No usable mkdir syscall
+#endif
 }

lib/linux/mknod.c

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2018,2019,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -21,9 +22,16 @@
 #include <linux/syscall.h>
 #include <arch/syscall.h>
 #include <sys/stat.h>
+#include <fcntl.h>
 
 int
 mknod (char const *file_name, mode_t mode, dev_t dev)
 {
+#if defined (SYS_mknod)
   return _sys_call3 (SYS_mknod, (long) file_name, (long) mode, (long) dev);
+#elif defined (SYS_mknodat)
+  return _sys_call4 (SYS_mknodat, AT_FDCWD, (long) file_name, (long) mode, (long) dev);
+#else
+#error No usable mknod syscall
+#endif
 }

lib/linux/pipe.c

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2018,2019,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -21,9 +22,16 @@
 #include <linux/syscall.h>
 #include <arch/syscall.h>
 #include <unistd.h>
+#include <fcntl.h>
 
 int
 pipe (int filedes[2])
 {
+#if defined (SYS_pipe)
   return _sys_call1 (SYS_pipe, (long) filedes);
+#elif defined (SYS_pipe2)
+  return _sys_call2 (SYS_pipe2, (long) filedes, 0);
+#else
+#error No usable pipe syscall found
+#endif
 }

lib/linux/readlink.c

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2018,2019,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -20,10 +21,17 @@
 
 #include <linux/syscall.h>
 #include <arch/syscall.h>
+#include <fcntl.h>
 #include <sys/stat.h>
 
 ssize_t
 readlink (char const *file_name, char *buffer, size_t size)
 {
+#if defined (SYS_readlink)
   return _sys_call3 (SYS_readlink, (long) file_name, (long) buffer, (long) size);
+#elif defined (SYS_readlinkat)
+  return _sys_call4 (SYS_readlinkat, AT_FDCWD, (long) file_name, (long) buffer, (long) size);
+#else
+#error No usable readlink syscall
+#endif
 }

lib/linux/rename.c

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2018,2019,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -21,9 +22,16 @@
 #include <linux/syscall.h>
 #include <arch/syscall.h>
 #include <unistd.h>
+#include <fcntl.h>
 
 int
 rename (char const *old_name, char const *new_name)
 {
+#if defined (SYS_rename)
   return _sys_call2 (SYS_rename, (long) old_name, (long) new_name);
+#elif defined (SYS_renameat2)
+  return _sys_call5 (SYS_renameat2, AT_FDCWD, (long) old_name, AT_FDCWD, (long) new_name, 0);
+#else
+#error No usable rename syscall
+#endif
 }

lib/linux/rmdir.c

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2016,2017,2018,2019,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -20,9 +21,16 @@
 
 #include <linux/syscall.h>
 #include <arch/syscall.h>
+#include <fcntl.h>
 
 int
 rmdir (char const *file_name)
 {
+#if defined (SYS_rmdir)
   return _sys_call1 (SYS_rmdir, (long) file_name);
+#elif defined (SYS_unlinkat)
+  return _sys_call3 (SYS_unlinkat, AT_FDCWD, (long) file_name, AT_REMOVEDIR);
+#else
+#error No usable rmdir syscall
+#endif
 }

lib/linux/signal.c

@@ -23,8 +23,7 @@
 #include <unistd.h>
 #include <signal.h>
 
-#if __i386__
+#if defined (SYS_rt_sigreturn)
-#else
 void
 _restorer_for_siginfo (void)
 {
@@ -36,8 +35,8 @@ sighandler_t
 signal (int signum, sighandler_t action)
 {
 #if __i386__
-  return (sighandler_t) _sys_call2 (SYS_signal, signum, (long) action);
+  return _sys_call2 (SYS_signal, signum, (long) action);
-#else
+#elif defined (SYS_rt_sigaction)
   static struct sigaction setup_action = { 0 };
   static struct sigaction old = { 0 };
   unsigned short bitindex;
@@ -68,5 +67,7 @@ signal (int signum, sighandler_t action)
   if (r)
     return 0;
   return old.sa_handler;
+#else
+#error no signal
 #endif
 }

lib/linux/sigprogmask.c

@@ -26,7 +26,7 @@
 int
 sigprocmask (int how, sigset_t const *set, sigset_t * oldset)
 {
-#if __i386__
+#if SYS_sigprocmask
   return _sys_call3 (SYS_sigprocmask, (long) how, (long) set, (long) oldset);
 #else
   return _sys_call3 (SYS_rt_sigprocmask, (long) how, (long) set, (long) oldset);

lib/linux/stat.c

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2016,2017,2018,2019,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -20,10 +21,17 @@
 
 #include <linux/syscall.h>
 #include <arch/syscall.h>
+#include <fcntl.h>
 #include <sys/stat.h>
 
 int
 stat (char const *file_name, struct stat *statbuf)
 {
+#if defined (SYS_stat)
   return _sys_call2 (SYS_stat, (long) file_name, (long) statbuf);
+#elif defined (SYS_newfstatat)
+  return _sys_call4 (SYS_newfstatat, AT_FDCWD, (long) file_name, (long) statbuf, AT_SYMLINK_NOFOLLOW);
+#else
+#error No usable stat syscall
+#endif
 }

lib/linux/symlink.c

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2018,2019,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -20,10 +21,17 @@
 
 #include <linux/syscall.h>
 #include <arch/syscall.h>
+#include <fcntl.h>
 #include <unistd.h>
 
 int
 symlink (char const *old_name, char const *new_name)
 {
+#if defined (SYS_symlink)
   return _sys_call2 (SYS_symlink, (long) old_name, (long) new_name);
+#elif defined (SYS_symlinkat)
+  return _sys_call3 (SYS_symlinkat, (long) old_name, AT_FDCWD, (long) new_name);
+#else
+#error No usable symlink syscall
+#endif
 }

lib/linux/unlink.c

@@ -1,6 +1,7 @@
 /* -*-comment-start: "//";comment-end:""-*-
  * GNU Mes --- Maxwell Equations of Software
  * Copyright © 2016,2017,2018,2019,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
  *
  * This file is part of GNU Mes.
  *
@@ -21,10 +22,17 @@
 #include <mes/lib.h>
 #include <linux/syscall.h>
 #include <arch/syscall.h>
+#include <fcntl.h>
 
 int
 unlink (char const *file_name)
 {
   long long_file_name = cast_charp_to_long (file_name);
+#if defined (SYS_unlink)
   return _sys_call1 (SYS_unlink, long_file_name);
+#elif defined (SYS_unlinkat)
+  return _sys_call3 (SYS_unlinkat, AT_FDCWD, long_file_name, 0);
+#else
+#error No usable unlink syscall
+#endif
 }